European Journal of Pharmacology (v.764, #C)

We synthesized and investigated the inhibitory effects of a novel niacinamide derivative, N-nicotinoyltyramine (NNT) on melanogenesis. NNT inhibited melanin production in B16F10 murine melanoma cells stimulated with α-melanocyte stimulating hormone (α-MSH), in human melanocyte and in three-dimensional cultured human skin model. NNT did not affect the catalytic activity of tyrosinase, but acted as an inhibitor of microphthalmia-associated transcription factor (MITF) and tyrosinase expressions in B16F10 cells. These findings suggest that the hypopigmentary effect of NNT results from the down-regulation of MITF and subsequently of tyrosinase, although NNT did not directly inhibit tyrosinase activity. In addition, safety of NNT was verified through performing neural stem cell morphology assay and Human repeated insult patch test as whitening agent. Our findings indicate that NNT may be a potential and non-skin irritant whitening agent for use in cosmetics and in the medical treatment of pigmentary disorders.
Keywords: N-Nicotinoyl tyramine; Melanogenesis; Microphthalmia-associated transcription factor (MITF); Pigmentation;

Deferoxamine modulates cytokines and growth factors to accelerate cutaneous wound healing in diabetic rats by Mahendra Ram; Vishakha Singh; Sanjay Kumawat; Dhirendra Kumar; Madhu C. Lingaraju; Thakur Uttam Singh; Anu Rahal; Surendra Kumar Tandan; Dinesh Kumar (9-21).
Deferoxamine has shown cutaneous wound healing potential by increased neovascularization. We hypothesized that topically applied deferoxamine facilitates wound healing in diabetic rats by modulating important cytokines and growth factors that take part in healing processes in a time-dependent manner. Diabetes was induced in male Wistar rats by streptozotocin and wound was created under pentobarbitone anesthesia. The diabetic rats were divided into two groups, of which one (control) was treated with ointment base and other with deferoxamine ointment (0.1%). Wound closure measurement and tissue collection were done on days 3, 7, 14 and 19 post-wounding. The relative expressions of hypoxia-inducible factor 1-alpha (HIF-1α), vascular endothelial growth factor (VEGF), stromal cell-derived factor 1-alpha (SDF-1α), transforming growth factor beta 1 (TGF-β1), tumor necrosis factor-alpha (TNF-α), matrix metalloproteinase-9 (MMP-9), interleukin-1 beta (IL-1β) and interleukin-10 (IL-10) mRNA and proteins were determined in the wound tissues. CD-31 staining and collagen content were evaluated by immunohistochemistry and picrosirius red staining, respectively. Histological changes were assessed by H&E staining. The per cent wound closure was significantly higher from day 7 onwards in deferoxamine-treated rats. HIF-1α, VEGF, SDF-1α, TGF-β1, IL-10 mRNA and their protein levels were significantly higher on days 3, 7 and 14 in deferoxamine-treated rats. The mRNA expression and protein levels of TNF-α, MMP-9 and IL-1β were progressively and markedly reduced in deferoxamine-treated rats. The collagen deposition and formation of blood vessels were greater in deferoxamine-treated rats. It is suggested that topical application of deferoxamine ointment might be useful in cutaneous wound healing in diabetic patients.
Keywords: Deferoxamine; Cytokines; Growth factors; Angiogenesis; Diabetic rats; Wound healing;

This study was performed to analyze the effect of carbon monoxide (CO)-releasing molecule-3 (CORM-3) in alleviating the production of proinflammatory mediators in macrophages treated with lipopolysaccharide (LPS) from Prevotella intermedia, a pathogen associated with periodontal disease, and its possible mechanisms of action. LPS was isolated using the hot phenol–water method. Culture supernatants were assayed for nitric oxide (NO) and interleukin-1β (IL-1β). Gene expression was quantified by real-time PCR, and protein expression by immunoblotting. DNA-binding activities of NF-κB subunits were determined using an ELISA-based kit. CORM-3 suppressed the production of inducible NO synthase (iNOS)-derived NO and IL-1β at both gene transcription and translation levels in P. intermedia LPS-activated RAW264.7 cells. CORM-3 enhanced heme oxygenase-1 (HO-1) expression in cells stimulated with P. intermedia LPS, and inhibition of HO-1 activity by SnPP notably reversed the suppressive effect of CORM-3 on LPS-induced production of NO. LPS-induced phosphorylation of p38 and JNK was not affected by CORM-3. CORM-3 did not influence P. intermedia LPS-induced degradation of IκB-α. Instead, nuclear translocation of NF-κB p65 and p50 subunits was blocked by CORM-3 in LPS-treated cells. In addition, CORM-3 reduced LPS-induced p65 and p50 binding to DNA. Besides, CORM-3 significantly suppressed P. intermedia LPS-induced phosphorylation of STAT1. Overall, this study indicates that CORM-3 suppresses the production of NO and IL-1β in P. intermedia LPS-activated murine macrophages via HO-1 induction and inhibition of NF-κB and STAT1 pathways. The modulation of host inflammatory response by CORM-3 would be an attractive therapeutic approach to attenuate the progression of periodontal disease.
Keywords: CORM-3; Lipopolysaccharide; Proinflammatory mediators; HO-1; NF-κB; STAT1;

Amitifadine, a triple monoamine re-uptake inhibitor, reduces nicotine self-administration in female rats by Edward D. Levin; Corinne Wells; Joshua E. Johnson; Amir H. Rezvani; Frank P. Bymaster; Jed E. Rose (30-37).
A wider diversity of drug treatments to aid smoking cessation is needed to help tailor the most efficacious treatment for different types of smokers. This study was conducted to determine whether amitifadine, which inhibits re-uptake of dopamine, norepinephrine and serotonin, would decrease nicotine self-administration at doses that do not cause adverse side effects. Adult female Sprague–Dawley rats were trained to self-administer nicotine intravenous (IV) and were given acute doses of amitifadine in a repeated measures counterbalanced design. Effects of amitifadine on locomotor activity and food motivated responding were also evaluated. Chronic amitifadine effects were also examined. The 30 mg/kg amitifadine dose significantly reduced nicotine self-administration. The 5 and 10 mg/kg doses reduced nicotine self-administration during the first 15 min of the session when the greatest amount of nicotine was self-administered. The 30 mg/kg amitifadine dose, but not the lower doses caused a significant reduction in locomotor activity averaged over the one-hour session and reduced food motivated responding. The 10 mg/kg dose caused hypoactivity at the beginning of the session, but 5 mg/kg did not cause any hypoactivity. The effects of chronic amitifadine treatment (10 mg/kg) over the course of 15 sessions was also determined. Amitifadine caused a significant reduction in nicotine self-administration, which was not seen to diminish over two consecutive weeks of treatment and a week after enforced abstinence. Amitifadine significantly reduced nicotine self-administration. This prompts further research to determine if amitifadine might be an effective treatment for smoking cessation.
Keywords: Amitifadine; Self-administration; Nicotine; Treatment; Dopamine; Serotonin; Norepinephrine;

The frog skin host-defense peptide CPF-SE1 improves glucose tolerance, insulin sensitivity and islet function and decreases plasma lipids in high-fat fed mice by Dinesh Srinivasan; Opeolu O. Ojo; Bosede O. Owolabi; J. Michael Conlon; Peter R. Flatt; Yasser H.A. Abdel-Wahab (38-47).
The frog skin host-defense peptide CPF-SE1 has previously been shown to stimulate the in vitro release of insulin from clonal BRIN-BD11 β-cells. In this study, the in vivo effects of the peptide were investigated in male NIH Swiss mice maintained on a high-fat diet to induce obesity and insulin resistance. Insulin-secretory responses of islets isolated from treated and untreated mice and changes in islet morphology were also examined. Total body fat, plasma glucagon, triglyceride and cholesterol concentrations were measured at the end of the treatment period. Acute intraperitoneal administration of CPF-SE1 (75 nmol body weight) to high-fat fed mice together with glucose (18 mmol/kg body weight) improved glucose tolerance and insulin responses compared to high-fat fed controls. Long term administration of CPF-SE1 (twice-daily administration of 75 nmol/kg body weight for 28 days) did not affect body weight or energy intake but decreased circulating glucose and increased insulin concentrations. Insulin sensitivity and insulin-secretory responses of islets to secretagogues were also significantly improved at 28 days in peptide-treated mice. In addition, significant decreases in plasma glucagon concentrations, pancreatic insulin and glucagon content, islet and beta cell area, body fat and plasma triglyceride levels were observed in CPF-SE1 treated with mice. In conclusion, CPF-SE1 improves beta cell function, insulin sensitivity and glycaemic control whilst reducing total body fat and circulating triglyceride levels. The peptide shows potential for development into an agent for treatment of patients with metabolic syndrome and type 2 diabetes.
Keywords: CPF-SE1; Amphibian skin peptide; Type 2 diabetes; Insulin sensitivity; Insulin-release; Metabolic syndrome;

The present study has been deliberated in order to compare the cardioprotective potential of 3-hydroxymethyl-glutaryl coenzyme A (HMG-CoA) reductase inhibitors, Atorvastatin and Simvastatin in hyperhomocysteinemic rat hearts. l-methionine (1.7 g/kg/day orally) was administered to rats for 4 weeks to produce experimental hyperhomocysteinemia (Hhcy). Isolated Langendorff-perfused normal and hyperhomocysteinemic rat hearts were subjected to global ischemia for 30 min followed by reperfusion for 120 min. The extent of myocardial damage was assessed in terms of myocardial infarct size using triphenyltetrazolium chloride (TTC) staining, and release of creatine kinase (CK) and lactate dehydrogenase (LDH) in the coronary effluent; whereas the oxidative stress in the heart was assessed by measuring lipid peroxidation, superoxide anion generation and reduced glutathione. Ischemia-reperfusion (I/R) was noted to produce myocardial injury in normal and hyperhomocysteinemic rat hearts, assessed in terms of increase in myocardial infarct size, LDH and CK in coronary effluent and oxidative stress. Treatment with Atorvatstain (50 µM) and Simvastatin (10 µM) afforded cardioprotection against I/R-induced myocardial injury in normal and hyperhomocysteinemic rat hearts as assessed in terms of reductions in myocardial infarct size, LDH and CK levels in coronary effluent and oxidative stress. It may be concluded that reductions in the high degree of oxidative stress may be responsible for the observed cardioprotective potential of Atorva-and Simvastatin, and both statins can be used interchangeably to afford cardioprotection against I/R-induced myocardial injury in normal and hyperhomocysteinemic rat hearts.
Keywords: Hyperhomocysteinemia; Atorvastatin; Simvastatin; Oxidative stress;

It has been reported that ischemic postconditioning (PC) changes the reperfusion pattern in permanent or transient models of stroke and confers neuroprotection. However, the effects of PC and subsequent use of tissue plasminogen activator (tPA) for the treatment of embolic stroke have not yet been investigated. Rats were subjected to stroke by injection of a preformed clot into the middle cerebral artery and randomly assigned to vehicle (saline 0.1 ml/100 g), tPA (3 mg/kg), PC only or PC+tPA (3 mg/kg). tPA was injected at 6 h after embolic stroke and PC was conducted at 6.5 h after ischemia by using five cycles of a 10 s occlusion and 30 s of reopening of the bilateral common carotid arteries. Cerebral blood flow (CBF) was monitored for 60 min from the time of tPA injection. Infarct size, blood brain barrier disruption, edema, neurological deficits, reactive oxygen species and apoptosis were measured 2 days later. PC decreased infarct volume, but PC+tPA was more neuroprotective than PC alone. While tPA alone dramatically increased CBF, conducting PC caused a gradual increase in CBF. A combination of PC+tPA reduced BBB leakage, brain edema, apoptosis and reactive oxygen species levels. Furthermore, a combination of PC+tPA improved neurological functions at 48 h after the induced stroke. In conclusion, PC hampered malignant hyperemia after reperfusion with tPA and extended its therapeutic window up to 6 h. Compared to PC alone, combination of thrombolysis and PC showed a better neuroprotection.
Keywords: Ischemic postconditioning; Embolic stroke; tPA; Hyperemia; Reperfusion injury;

The purpose of this study was to identify conditions that will increase the sensitivity of drug-resistant cancer cells. Selenium derivatives have been shown to present anti-cancer properties in the clinic. Currently, selenate, selenite, selenomethionine (SeMet), methyl-selenocysteine (MSC), and methaneselenic acid (MSA) are the most common selenium derivatives used as drugs in humans. Herein, we tested whether these selenium derivatives can sensitize KBV20C cancer cells, which are highly resistant to anti-cancer drugs such as vincristine. All five drugs could sensitize KBV20C cells to the same extent as they sensitized the sensitive parent KB cells, suggesting that selenium-derived drugs can be used for drug-resistant cancer cells. We also observed that these drugs did not inhibit the P-glycoprotein (P-gp) pumping-out ability, suggesting that the sensitization by selenium-derived drugs does not depend on P-gp activity in resistant KBV20C cells. Interestingly, using a cell viability assay, microscopic observation, and Hoechst staining, we found that selenate highly sensitized drug-resistant KBV20C cells by activating the apoptotic pathway, when compared to sensitive KB cells.Furthermore, we investigated why selenate sensitizes resistant KBV20C cells. Selenate-induced toxicity was associated with an increase in G2-phase cell cycle arrest in KBV20C cells, suggesting that the selenate-induced increase in apoptosis resulted from cell cycle arrest in resistant KBV20C cells. Our findings may contribute to the development of selenate-based therapies for patients resistant to cancer drugs.
Keywords: Selenite; Selenium-related drugs; G2-arrest; P-gp; Drug-resistance;

The effects of eucalyptol (1,8-cineole) were studied on the activity of central neurons of land snail Caucasotachea atrolabiata. Eucalyptol (3 mM) depolarized the membrane potential and increased the frequency of spontaneous activity in a time dependent and reversible manner. These effects were associated with suppression of afterhyperpolarization and significant reduction of amplitude and slope of rising and falling phases of action potentials. While the eucalyptol-induced suppression of action potential amplitude and rising slope were essentially dependent on membrane depolarization, its actions on repolarization slope and afterhyperpolarization were not affected by resetting the membrane potential close to the control value. These findings suggest an inhibitory action on the potassium channels that underlie repolarization and afterhyperpolarization. Eucalyptol also increased the frequency of driven action potentials but suppressed the post stimulus inhibitory period, indicating an inhibitory action on calcium-activated potassium channels.A higher concentration of eucalyptol, 5 mM, reversibly changed the pattern of activity to burst firing associated with paroxysmal depolarization shift (PDS). Low doses of eucalyptol and potassium channel blockers, tetraethylammonium and 4-aminopyridine, synergistically acted to induce burst firing. At high concentration (30 mM), tetraethylammonium was able to induce burst firing and PDS. The sodium currents and ion channel phosphorylation by protein kinases A and C were not required for the eucalyptol-induced epileptiform activity, but calcium currents were essential for this action. Our findings show the excitatory and epileptogenic action of eucalyptol, which is most likely mediated through direct inhibitory action on potassium channels.
Keywords: Eucalyptol; Snail neuron; Burst firing; Excitability; Potassium channel; Calcium channel;

Fisetin regulates TPA-induced breast cell invasion by suppressing matrix metalloproteinase-9 activation via the PKC/ROS/MAPK pathways by Eun-Mi Noh; Yeon-Ju Park; Jeong-Mi Kim; Mi-Seong Kim; Ha-Rim Kim; Hyun-Kyung Song; On-Yu Hong; Hong-Seob So; Sei-Hoon Yang; Jong-Suk Kim; Samg Hyun Park; Hyun-Jo Youn; Yong-Ouk You; Ki-Bang Choi; Kang-Beom Kwon; Young-Rae Lee (79-86).
Invasion and metastasis are among the main causes of death in patients with malignant tumors. Fisetin (3,3′,4′,7-tetrahydroxyflavone), a natural flavonoid found in the smoke tree (Cotinus coggygria), is known to have antimetastatic effects on prostate and lung cancers; however, the effect of fisetin on breast cancer metastasis is unknown. The aim of this study was to determine the anti-invasive activity of fisetin in human breast cancer cells. Matrix metalloproteinase (MMP)-9 is a major component facilitating the invasion of many cancer tumor cell types, and thus the inhibitory effect of fisetin on MMP-9 expression in 12-O-tetradecanoylphorbol-13-acetate (TPA)-stimulated human breast cancer cells was investigated in this study. Fisetin significantly attenuated TPA-induced cell invasion in MCF-7 human breast cancer cells, and was found to inhibit the activation of the PKCα/ROS/ERK1/2 and p38 MAPK signaling pathways. This effect was furthermore associated with reduced NF-κB activation, suggesting that the anti-invasive effect of fisetin on MCF-7 cells may result from inhibited TPA activation of NF-κB and reduced TPA activation of PKCα/ROS/ERK1/2 and p38 MAPK signals, ultimately leading to the downregulation of MMP-9 expression. Our findings indicate the role of fisetin in MCF-7 cell invasion, and clarify the underlying molecular mechanisms of this role, suggesting fisetin as a potential chemopreventive agent for breast cancer metastasis.Display Omitted
Keywords: Fisetin; MMP-9; Invasion; PKCα; MCF-7;

Propofol depresses cerebellar Purkinje cell activity via activation of GABAA and glycine receptors in vivo in mice by Ri Jin; Heng Liu; Wen-Zhe Jin; Jin-Di Shi; Qing-Hua Jin; Chun-Ping Chu; De-Lai Qiu (87-93).
Propofol is an intravenous sedative-hypnotic agen, which causes rapid and reliable loss of consciousness. Under in vitro conditions, propofol activates GABAA and glycine receptors in spinal cord, hippocampus and hypothalamus neurons. However, the effects of propofol on the cerebellar neuronal activity under in vivo conditions are currently unclear. In the present study, we examined the effects of propofol on the spontaneous activity of Purkinje cells (PCs) in urethane-anesthetized mice by cell-attached recording and pharmacological methods. Our results showed that cerebellar surface perfusion of propofol (10–1000 μM) induced depression of the PC simple spike (SS) firing rate in a dose-dependent manner, but without significantly changing the properties of complex spikes (CS). The IC50 of propofol for inhibiting SS firing of PCs was 144.5 μM. Application of GABAA receptor antagonist, SR95531 (40 μM) or GABAB receptor antagonist, saclofen (20 μM), as well as glycine receptor antagonist, strychnine (10 μM) alone failed to prevent the propofol-induced inhibition of PCs spontaneous activity. However, application the mixture of SR95531 (40 μM) and strychnine (10 μM) completely blocked the propofol-induced inhibition of PC SS firing. These data indicated that cerebellar surface application of propofol depressed PC SS firing rate via facilitation of GABAA and functional glycine receptors activity in adult cerebellar PCs under in vivo conditions. Our present results provide a new insight of the anesthetic action of propofol in cerebellar cortex, suggesting that propofol depresses the SS outputs of cerebellar PCs which is involved in both GABAA and glycine receptors activity.
Keywords: Propofol; Cerebellar Purkinje cell; Cell-attached recording; GABAergic receptor; Glycine receptor;

Signal pathways involved in the biological effects of sulfur dioxide by Xin-Bao Wang; Jun-Bao Du; Hong Cui (94-99).
Gasotransmitters, such as nitric oxide, carbon monoxide and hydrogen sulfide, play important roles in life and have attracted great interest in scientists. In recent years, sulfur dioxide (SO2) has also been found to play important roles in mammals. The redox pathway is involved in the biological effects of SO2, such as the protective effect on myocardial ischemia reperfusion, myocardial injury, pulmonary hypertension and atherosclerosis. Ion channels, such as L-type calcium and adenosine triphosphate-sensitive potassium channels, as well as 3′–5′-cyclic guanosine monophosphate and 3′–5′-cyclic adenosine monophosphate pathways are also involved in the vasorelaxant effect of SO2. The mitogen-activated protein kinase pathway plays roles in vascular remodeling during pulmonary hypertension and vascular smooth muscle cell proliferation. Understanding these signaling mechanisms would help to clarify the pathophysiological effect and therapeutic potential of SO2.
Keywords: Sulfur dioxide; Gasotransmitter; Signal pathway; Biology;

Anti-fatigue effect of Myelophil in a chronic forced exercise mouse model by Jin-Seok Lee; Hyeong-Geug Kim; Jong-Min Han; Young-Ae Kim; Chang-Gue Son (100-108).
This study was performed to evaluate the anti-fatigue effects of Myelophil. ICR male mice (10 weeks old) were forced to run for 1 hour, 5 days/week for 4 weeks. Each running session was followed by administration of distilled water, Myelophil (50 or 100 mg/kg), or ascorbic acid (100 mg/kg) 1 h later. Equal proportions of Astragali Radix and Salviae Miltiorrhizae Radix were extracted using 30% ethanol, and formulated into Myelophil. To evaluate the anti-fatigue effects of Myelophil, exercise tolerance and forced swimming tests were conducted. Underlying mechanisms, including oxidant–antioxidant balance, inflammatory response, and energy metabolism, were investigated by analyzing skeletal muscle tissues and/or sera. Myelophil significantly increased exercise ability and latency times, and decreased the number of electric shocks and immobility time on exercise tolerance and forced swimming tests compared with control group. Myelophil also significantly ameliorated fatigue-induced alterations in oxidative stress biomarkers, antioxidant enzymes and antioxidant capacity, as measured by multiple assays, including enzyme activity assays and western blotting, as well as alterations in pro- and anti-inflammatory cytokines in skeletal muscle. Furthermore, Myelophil normalized alterations in energy metabolic markers in sera. These findings suggest that Myelophil reduces the effects of chronic fatigue, likely by attenuating oxidative and inflammatory responses and normalizing energy metabolism. Consequently, this study provides evidence for the clinical relevance of Myelophil.Display Omitted
Keywords: Chronic fatigue; Chronic forced exercise; Oxidative stress; Antioxidant; Myelophil;

Hyper-osmolarity and calcium chelation: Effects on cystic fibrosis mucus by Anna Ermund; Lauren N. Meiss; Jenny K. Gustafsson; Gunnar C. Hansson (109-117).
A non-functional Cystic Fibrosis Transmembrane conductance Regulator (CFTR) leads to the disease cystic fibrosis (CF). Although the CFTR is expressed in multiple organs, pulmonary disease is the major cause of illness and death in patients with CF. Stagnant mucus, causing airway obstruction, bacterial overgrowth, persistent inflammation and tissue destruction characterizes the disease, but how the defect in CFTR function is coupled to the mucus phenotype is still controversial. We have recently shown that bicarbonate ions passing through CFTR are necessary for proper unfolding of the MUC2 mucin, thus highlighting the importance of bicarbonate ion transport via the CFTR and the ability of these ions to raise the pH and chelate calcium bound to the mucin as the important steps in forming normal mucus. In order to find potential CF treatments and expand our knowledge about the usefulness of bicarbonate as an active ingredient in formulations to alleviate mucus plugging, we used an Ussing-type chamber and explants from the F508del-CFTR mutant mouse ileum to test the effect of calcium chelators on mucus attachment, either in isolation or in combination with osmolytes such as mannitol or hypertonic saline. We found that increasing the concentration of bicarbonate, both alone or in combination with increased osmolarity of the solution, detached the otherwise attached CF mucus.
Keywords: Calcium chelator; Hyperosmolarity; Mouse ileum; Mucus attachment; Osmolyte;

The important role played by aryl hydrocarbon receptor activation in the pathophysiology of atherosclerosis induced by cigarette smoke exposure has spurred the clinical interest in the development of aryl hydrocarbon receptor antagonists with atheroprotective efficacy. A few aryl hydrocarbon receptor antagonists were developed but the lack of structural information regarding the receptor ligand binding domain resulted in several limitations in the pharmacological properties of these compounds including partial agonism, allosterism, non-selectivity, cytotoxicity and susceptibility to bioactivation. These limitations make the progress of preclinical and clinical assays with the available aryl hydrocarbon receptor antagonists difficult. There is a great interest in developing pure, competitive, selective, nontoxic and resistant to bioactivation aryl hydrocarbon receptor antagonists. Current technology permits the development of pharmacologically ideal antagonists based on the chemical features of the aryl hydrocarbon receptor ligand binding domain. According to these characteristics, chlorinated derivatives of trans-stilbene meta-substituted with electrophilic aromatic directing groups would be effective prototypes for pure, competitive, selective, nontoxic and resistant to bioactivation antagonists for such receptor.
Keywords: Atherosclerosis; Cigarette smoke; Aryl hydrocarbon receptor antagonists; Molecular modeling; Drug design;

Physcion induces mitochondria-driven apoptosis in colorectal cancer cells via downregulating EMMPRIN by Xuehong Chen; Hui Gao; Yantao Han; Junli Ye; Jing Xie; Chunbo Wang (124-133).
Physcion, an anthraquinone derivative widely isolated and characterized from both terrestrial and marine sources, has anti-tumor effects on a variety of carcinoma cells, mainly through inhibition of cell proliferation, apoptosis induction and cell cycle arrest. However, little is known about the mechanisms underlying its role in tumor progression. In the present study, we investigated the molecular mechanisms involved in physcion-induced apoptosis in human colorectal cancer (CRC) lines HCT116. Our results showed that physcion inhibited tumor cell viability in a dose- and time-dependent manner, and induced cell apoptosis via intrinsic mitochondrial pathway. Our results also revealed that physcion treatment significantly inhibited extracelluar matrix metalloproteinase inducer (EMMPRIN) expression in HCT116 cells in a dose-dependent manner and overexpression of EMMPRIN protein markedly reduced physcion-induced cell apoptosis. Furthermore, our results strongly indicated the modulating effect of physcion on EMMPRIN is correlated with AMP-activated protein kinase (AMPK)/Hypoxia-inducible factor 1α (HIF-1α) signaling pathway. Our data provide the first experimental evidence that physcion induces mitochondrial apoptosis in CRC cells by downregulating of EMMPRIN via AMPK/HIF-1α signaling pathway and suggest a new mechanism to explain its anti-tumor effects.
Keywords: Physcion; Apoptosis; EMMPRIN; AMPK; HIF-1α;

Hyperlipidemia can be harmful to the pancreas and β3-adrenoceptor agonist can improve lipid metabolism disorder. We aimed to study the effects of β3-adrenoceptor activation on glucose, insulin and the expression of pancreatic adrenoceptors and angiotensin II receptors. Ten C57BL/6J mice at the age of 10 weeks served as normal control, and forty age-matched apolipoprotein E knockout (ApoE−/−) mice were randomly divided into hyperlipidaemia model group, low-dose and high-dose β3-adrenoceptor agonist group and β3-adrenoceptor antagonist group. After 26 weeks of high-fat diet, treatments were given for 12 weeks. Serum glucose and insulin levels in 48 weeks old mice were measured using an automatic biochemical detector. Quantitative rt-PCR and Western blot were used to analyze the mRNA and protein expression of α1A-, α2A-, β2-, β3-adrenoceptors and angiotensin II type 1 and type 2 receptors in pancreas. We found that β3-adrenoceptor agonist could decrease serum glucose and insulin levels in aged ApoE−/− mice (P<0.01) and down-regulate the expression of α1A-adrenoceptor and angiotensin II type 1 receptor which were significantly increased in model mice (P<0.05, P<0.01). Compared with the model mice, α2A-, β2-, β3-adrenoceptor and angiotensin II type 2 receptor expression were up-regulated in β3-adrenoceptor agonist treat mice (P<0.05, P<0.01). These results suggest that chronic β3-adrenoceptor activation regulated the expression of adrenoceptors and angiontensin II receptors towards contrary direction, which indicates that there are interactions between β3-adrenoceptor and subtypes of adrenoceptor and angiotensin II receptor, and these interactions may play a protective role in pancreas and improve glucose metabolism disorders.
Keywords: β3-adrenoceptor agonist; Glucose; Insulin; Adrenoceptor; Angiotensin II receptor;

Bench-to-bedside pharmacology of adrenomedullin by Johji Kato; Kazuo Kitamura (140-148).
The bioactive peptide adrenomedullin (AM) exerts pleiotropic actions in various organs and tissues. In the heart, AM has an inhibitory effect on ventricular remodeling, suppressing cardiomyocyte hypertrophy and the proliferation of cardiac fibroblasts. This pharmacological property was shown not only in rat models of acute myocardial infarction, but also clinically in patients with this cardiac disease. An originally characterized feature of AM was a potent vasodilatory effect, but this peptide was found to be important for vascular integrity and angiogenesis. AM-induced angiogenesis is involved in tumor growth, while AM inhibits apoptosis of some types of tumor cell. A unique pharmacological property is anti-inflammatory activity, which has been characterized in sepsis and inflammatory bowel diseases; thus, there is an ongoing clinical trial to test the efficacy of AM for patients with intractable ulcerative colitis. These activities are assumed to be mediated via the specific receptor formed by calcitonin receptor-like receptor and receptor activity-modifying protein 2 or 3, while some questions remain to be answered about the molecular mechanisms of this signal transduction system. Taking these findings together, AM is a bioactive peptide with pleiotropic effects, with potential as a therapeutic tool for a wide range of human diseases from myocardial infarction to malignant tumors or inflammatory bowel diseases.
Keywords: Adrenomedullin; Cardiovascular protection; Angiogenesis; Cerebral protection; Tumor growth; Anti-inflammation;

Semaphorin 7A plays a critical role in IgE-mediated airway inflammation in mice by Nobuaki Mizutani; Takeshi Nabe; Shin Yoshino (149-156).
Elevated allergen-specific IgE levels are a hallmark of allergic asthma, a disease involving chronic airway inflammation characterized by airway hyperresponsiveness (AHR); neutrophilic airway inflammation is found in patients with severe asthma. Furthermore, we have reported that interleukin (IL)-33 and IL-17A contribute to IgE-mediated AHR through neutrophilic inflammation in mice. Meanwhile, semaphorins regulating neuronal and immune function have been focused on in several diseases. Here, we investigated whether semaphorin 7A (SEMA7A) is related to IgE-mediated neutrophilic inflammation in mice. BALB/c mice sensitized with antigen-specific IgE monoclonal antibody were repeatedly challenged by the antigen. When anti-SEMA7A antibody was administered during the fourth to seventh challenges, the infiltration by macrophages, lymphocytes, neutrophils, and eosinophils in the lungs was reduced at the seventh challenge (P<0.05, 0.05, 0.01, and 0.05, respectively). However, the increased production of IL-4, IL-5, IL-13, IL-33, IL-17A, IL-6, and CXCL1 in the lungs was not suppressed. In histological analysis, the epithelial cells, blood vessels, and inflammatory cells in the lungs of IgE-sensitized mice showed SEMA7A expression; plexin C1 for the receptor was expressed in the inflammatory cells. Meanwhile, we examined the effect of anti-SEMA7A antibody on AHR and neutrophilic inflammation enhanced by the collaborative action of IL-33 and IL-17A in normal mice, resulting in the suppression of these responses (P<0.05 and 0.01, respectively). Collectively, we demonstrated that SEMA7A plays a critical role in IgE-mediated neutrophilic airway inflammation. Therefore, SEMA7A may be a potential therapeutic target for severe allergic asthma showing neutrophilic airway inflammation.
Keywords: Semaphorin 7A; Plexin C1; Asthma; IgE; Neutrophil; Airway hyperresponsiveness;

The effects of polyamines on human colonic mucosal function by Ailín C. Rogers; Frank D. McDermott; Helen M. Mohan; P. Ronan O’Connell; Desmond C. Winter; Alan W. Baird (157-163).
Electrogenic ion transport in human colon is a surrogate marker for colonic mucosal function, and may be manipulated by a variety of hormonal, neural, immune and paracrine mediators. Polyamines are present in vast quantities in the colonic lumen and appear to be integral to cellular function. This study explores some of the mechanisms of polyamine action on colonic tissue through study of their effects on differential secretory pathways, as well as examining their actions on intracellular cAMP and Ca2+ accumulation.Human colonic mucosa was mounted in Ussing chambers and treated with polyamines (spermine, spermidine and putrescine) with changes in ion transport recorded. In separate experiments colonic crypts were treated with polyamines and intracellular cAMP levels determined by ELISA and intracellular calcium concentrations were quantified by fluorescent imaging.Polyamines at physiological concentrations (1 mM) exert no effects on basal mucosal chloride secretion or transepithelial electrical resistance. Polyamines inhibit electrogenic ion secretion as stimulated by forskolin (cAMP-mediated), but not carbachol (Ach-mediated). All the polyamines used in this study inhibited intracellular cAMP accumulation, according to potency (spermine>spermidine>putrescine). Spermine increased intracellular Ca2+ in a PKC-dependent manner, likely due to its effects on the extracellular calcium-sensing receptor (CaSR).Polyamines act to prevent cAMP-mediated Cl hypersecretion in the colon, acting through CaSR to inhibit PKC-mediated [Ca2+]i release from intracellular stores.
Keywords: Polyamines; Colon; Calcium-sensing receptor; Ussing chambers;

Nesfatin-1 is a novel anorexigenic peptide that regulates feeding behavior and gastrointestinal function. This study aimed to explore the effects of nesfatin-1 on gastric distension (GD)-sensitive neurons in the basomedial amygdala (BMA) and the potential mechanism for nesfatin-1 to regulate gastric motility through the arcuate nucleus (Arc). The projection of nerve fiber and expression of nesfatin-1 were observed by retrograde tracing and fluo-immunohistochemistry staining. Single-unit discharges in the BMA were recorded extracellularly, and gastric motility in conscious rats was monitored. Results showed that the nesfatin-1/ fluorogold-double labeled neurons were observed in the Arc. Nesfatin-1 could excite the GD-excitatory neurons and inhibit the GD-inhibitory neurons in the BMA. Gastric motility and gastric emptying were significantly reduced by nesfatin-1 administration to the BMA in a dose-dependent manner. The effects of nesfatin-1 could be partially blocked by melanocortin 3/4 receptors antagonist, SHU9119. Electrical stimulation of the Arc significantly excited the response of GD neurons to nesfatin-1 and promoted gastric motility. Nevertheless, these effects could be mitigated by pretreatment with anti-NUCB2/nesfatin-1 antibody. It is suggested that nesfatin-1 in the BMA plays an important role in decreasing gastric motility and the Arc may be involved in this regulation process.
Keywords: Nesfatin-1; Amygdala; Arcuate nucleus; Gastric distension responsive neurons; Gastric motility;

MAS receptors mediate vasoprotective and atheroprotective effects of candesartan upon the recovery of vascular angiotensin-converting enzyme 2–angiotensin-(1-7)–MAS axis functionality by Larissa Pernomian; Alejandro F. do Prado; Mayara S. Gomes; Laena Pernomian; Carlos H.T.P. da Silva; Raquel F. Gerlach; Ana M. de Oliveira (173-188).
AT1 antagonists effectively prevent atherosclerosis since AT1 upregulation and angiotensin II-induced proinflammatory actions are critical to atherogenesis. Despite the classic mechanisms underlying the vasoprotective and atheroprotective actions of AT1 antagonists, the cross-talk between angiotensin-converting enzyme-angiotensin II-AT1 and angiotensin-converting enzyme 2–angiotensin-(1-7)–MAS axes suggests other mechanisms beyond AT1 blockage in such effects. For instance, angiotensin-converting enzyme 2 activity is inhibited by reactive oxygen species derived from AT1-mediated proinflammatory signaling. Since angiotensin-(1-7) promotes antiatherogenic effects, we hypothesized that the vasoprotective and atheroprotective effects of AT1 antagonists could result from their inhibitory effects on the AT1-mediated negative modulation of vascular angiotensin-converting enzyme 2–angiotensin-(1-7)–MAS axis functionality. Interestingly, our results showed that early atherosclerosis triggered in thoracic aorta from high cholesterol fed-Apolipoprotein E-deficient mice impairs angiotensin-converting enzyme 2–angiotensin-(1-7)–MAS axis functionality by a proinflammatory-redox AT1-mediated pathway. In such mechanism, AT1 activation leads to the aortic release of tumor necrosis factor-α, which stimulates NAD(P)H oxidase/Nox1-driven generation of superoxide and hydrogen peroxide. While hydrogen peroxide inhibits angiotensin-converting enzyme 2 activity, superoxide impairs MAS functionality. Candesartan treatment restored the functionality of angiotensin-converting enzyme 2–angiotensin-(1-7)–MAS axis by inhibiting the proinflammatory-redox AT1-mediated mechanism. Candesartan also promoted vasoprotective and atheroprotective effects that were mediated by MAS since A779 (MAS antagonist) co-treatment inhibited them. The role of MAS receptors as the final mediators of the vasoprotective and atheroprotective effects of candesartan was supported by the vascular actions of angiotensin-(1-7) upon the recovery of the functionality of vascular angiotensin-converting enzyme 2–angiotensin-(1-7)–MAS axis.High-cholesterol (1%) diet-fed Apolipoprotein E-deficient (ApoE−/ ) mice develop mild hypercholesterolemia that triggers early atherosclerosis in the thoracic aortic branch. This process increases vascular AT1 functionality, which leads to endothelial dysfunction, the expression of acute inflammatory mediators and the deposition of elastin and type I-collagen. Early atherosclerosis also impairs the functionality of local angiotensin-converting enzyme 2 (ACE2)–angiotensin-(1-7)–MAS axis by a proinflammatory-redox AT1-mediated pathway. In this mechanism, the activation of vascular AT1 receptors leads to the release of high amounts of tumor necrosis factor-α (TNF-α), which upregulates the local Nox1 in generating superoxide (O2 ). The high levels of O2 lead to the local generation of high levels of hydrogen peroxide (H2O2) by dismutation. H2O2 impairs local ACE2 activity in generating angiotensin-(1-7) upon the activation of activating volume-sensitive chloride currents (I Cl,SWELL) while O2 inhibits the local nitrergic MAS-mediated relaxation. The chronic treatment with candesartan restores the functionality of vascular ACE2–angiotensin-(1-7)–MAS axis upon the inhibition of the proinflammatory-redox AT1-mediated mechanism. Candesartan treatment also promotes vasoprotective and atheroprotective effects that are finally mediated by MAS receptors upon the recovery of ACE2–angiotensin-(1-7)–MAS axis functionality.Display Omitted
Keywords: Early atherosclerosis; AT1 receptors; Angiotensin-converting-enzyme 2; Angiotensin-(1-7); MAS receptors; Candesartan;

Fibroblast growth factor 21 prevents glycemic deterioration in insulin deficient mouse models of diabetes by Birgitte Andersen; Bilal A. Omar; Günaj Rakipovski; Kirsten Raun; Bo Ahrén (189-194).
In type 1 diabetes, there is a rapid loss of glycemic control immediately after onset of the disease. We aimed to determine if the deterioration of glycemic control that occurs early after the onset of insulin-deficient diabetes could be blunted by treatment with recombinant fibroblast growth factor 21 (FGF21). Normal C57BL/6J mice made diabetic by a single high dose injection of streptozotocin (STZ) were randomized to receive twice daily subcutaneous injection of vehicle or recombinant human FGF21 at doses of 0.3 and 1.0 mg/kg for 10 days. Body weight was recorded daily and 5 h fasted glucose, insulin, glucagon, free fatty acids and ketones were determined at 6 and 10 days post-randomization.The increase in fasting plasma glucose induced by STZ in untreated mice was prevented with FGF21 at 0.3 mg/kg BID. In contrast, at 1.0 mg/kg BID, FGF21 did not prevent the rise in plasma glucose after STZ. At the end of the study, plasma glucagon was significantly higher in the diabetic group treated with FGF21 1.0 mg/kg BID than in the untreated group. This was not seen for the group treated with FGF21 0.3 mg/kg BID. There were significant dose dependent reductions in plasma free fatty acids with FGF21 treatment but no significant change in plasma ketones (β-hydroxybutyrate). FGF21 treatment did not have significant effects on body weight in lean insulin deficient mice.In conclusion, FGF21 prevents increases in glycaemia and has lipid lowering properties in mouse models of insulin deficient diabetes, although by increasing the dose increased glucagon levels are seen and hyperglycemia persists.
Keywords: FGF21; Type 1 diabetes; Glucose; Glucagon;

Naringenin improves learning and memory in an Alzheimer's disease rat model: Insights into the underlying mechanisms by Saeed Ghofrani; Mohammad-Taghi Joghataei; Simin Mohseni; Tourandokht Baluchnejadmojarad; Maryam Bagheri; Safoura Khamse; Mehrdad Roghani (195-201).
Alzheimer's disease (AD) is one of the prevalent neurological disorders of the central nervous system hallmarked by increased beta-amyloid (Aβ) deposition and ensuing learning and memory deficit. In the present study, the beneficial effect of naringenin on improvement of learning and memory was evaluated in an Alzheimer's disease rat model. The Aβ-injected rats showed a lower alternation score in Y-maze task, impairment of retention and recall capability in passive avoidance test, and lower correct choices and higher errors in radial arm maze (RAM) task as compared to sham group in addition to enhanced oxidative stress and apoptosis. Naringenin, but not a combination of naringenin and fulvestrant (an estrogenic receptor antagonist) significantly improved the performance of Aβ-injected rats in passive avoidance and RAM tasks. Naringenin pretreatment of Aβ-injected rats also lowered hippocampal malondialdehyde (MDA) with no significant effect on nitrite and superoxide dismutase (SOD) activity in addition to lowering apoptosis. These results suggest naringenin pretreatment attenuates Aβ-induced impairment of learning and memory through mitigation of lipid peroxidation and apoptosis and its beneficial effect is somewhat mediated via estrogenic pathway.
Keywords: Naringenin; Alzheimer's disease; Beta-amyloid; Learning and memory; Oxidative stress; Apoptosis;

Platelet-activating factor (PAF), a potent lipid mediator, is implicated in many inflammatory diseases, and therefore may serve as a direct target for anti-inflammatory drugs. We previously reported that synthetic biotinylated peptides having a Tyr-Lys-Asp-Gly sequence markedly inhibit PAF-induced inflammation by direct binding, and that two synthetic fluorescence-labelled heptapeptides (Lys-Trp-Tyr-Lys-Asp-Gly-Asp and d-Lys-Trp-Tyr-Lys-Asp-Gly-Asp) with high stability in plasma specifically bind to PAF-like lipids (oxidized- and lyso-phosphatidylchoine). In this study, synthetic heptapeptides (Lys-Trp-Tyr-Lys-Asp-Gly-Asp) coupled to a biotin molecule through the N-terminal amino group and ε-amino group of N-terminus Lys, (Btn)KP6 and K(Btn)P6, respectively, and their biotinylated peptides substituted with d-Lys at the N-terminus, (Btn)dKP6 and dK(Btn)P6, respectively, were investigated for their effects on PAF-induced inflammation. In the experiments using a rat model of hind paw oedema, (Btn)KP6, K(Btn)P6, (Btn)dKP6, and dK(Btn)P6 significantly inhibited PAF-induced paw oedema, with the highest inhibitory effect exhibited by dK(Btn)P6. The inhibitory effect of d-Tyr-d-Lys-d-Asp-Gly tetrapeptide on PAF-induced paw oedema was much lower than that of Tyr-Lys-Asp-Gly tetrapeptide. In the experiments using tryptophan fluorescence spectroscopy, (Btn)KP6, K(Btn)P6, (Btn)dKP6, and dK(Btn)P6 bound to PAF dose-dependently, with dK(Btn)P6 showing the strongest binding affinity, indicating that its affinity appears to be closely correlated with its inhibitory effect on PAF-induced inflammation. These results suggest that direct binding of (Btn)KP6, K(Btn)P6, (Btn)dKP6, and dK(Btn)P6 to PAF can lead to marked inhibition of PAF-induced inflammation, and these agents, particularly dK(Btn)P6, may be useful as anti-inflammatory drugs targeting PAF with high stability in plasma.
Keywords: Platelet-activating factor; Inflammation; Biotinylated peptide; D-Amino acid; Anti-inflammatory drug;

Genetic deletion and pharmacological inhibition of Akt1 isoform attenuates bladder cancer cell proliferation, motility and invasion by Harika Sabbineni; Abdulrahman Alwhaibi; Anna Goc; Fei Gao; Alanna Pruitt; Payaningal R. Somanath (208-214).
Isoform specific expression, intracellular localization and function of Akt in bladder cancer are not known. In the current study, we identified Akt1, followed by Akt2 and Akt3 as the predominant Akt isoform in human T24 and UM-UC-3 metastatic bladder cancer cells. Whereas Akt1 is localized at the membrane, cytoplasm and nucleus, Akt2 is solely cytoplasmic and Akt3 is mostly localized in the nucleus in T24 cells. ShRNA-mediated Akt1 knockdown resulted in impaired T24 cell survival, proliferation, colony formation, migration and microinvasion. Whereas pharmacological inhibition of Akt1 resulted in impaired T24 and UM-UC-3 cell motility, viability and proliferation, effect of pharmacological inhibition by Akt2 inhibitor was limited to proliferation in T24, but not UM-UC-3 cells. Our data provide important clues on the therapeutic benefits of targeting Akt1 for bladder cancer therapy.
Keywords: Akt1; Akt2; Akt3; Bladder cancer; Proliferation; Invasion;

The inhibitory effect of locally injected dexmedetomidine on carrageenan-induced nociception in rats by Yuka Honda; Hitoshi Higuchi; Yoshikazu Matsuoka; Akiko Yabuki-Kawase; Minako Ishii-Maruhama; Yumiko Tomoyasu; Shigeru Maeda; Hiroshi Morimatsu; Takuya Miyawaki (215-219).
Recent studies showed that the administration of dexmedetomidine relieved hyperalgesia in the presence of neuropathic pain. These findings have led to the hypothesis that the local administration of dexmedetomidine is useful for relieving acute inflammatory nociception, such as postoperative pain. Thus, we evaluated the inhibitory effect of locally injected dexmedetomidine on acute inflammatory nociception. Acute inflammatory nociception was induced by an intraplantar injection of 1% carrageenan into the hindpaws of rats, and dexmedetomidine was also injected combined with carrageenan. The paw withdrawal threshold based on von Frey filament stimulation was measured until 12 h after injection. We compared the area under the time-curve (AUC) between carrageenan and carrageenan with dexmedetomidine. To clarify that the action of dexmedetomidine was via α2-adrenoceptors, we evaluated the effect of yohimbine, a selective antagonist of α2-adrenoceptors, on the anti-nociception of dexmedetomidine. As the results, the intraplantar injection of carrageenan with over 10 μM dexmedetomidine significantly increased AUC, compared to that with only carrageenan injection. This effect of dexmedetomidine was reversed by the addition of yohimbine to carrageenan and dexmedetomidine. These results demonstrated that the locally injected dexmedetomidine was effective against carrageenan-induced inflammatory nociception via α2-adrenoceptors. The findings suggest that the local injection of dexmedetomidine is useful for relieving local acute inflammatory nociception.
Keywords: Dexmedetomidine; α2-Adrenoceptors; Anti-nociception; Inflammatory pain; Pain relief;

Biochemical characterization of smoothened receptor antagonists by binding kinetics against drug-resistant mutant by Yuji Shimizu; Tsuyoshi Ishii; Kazumasa Ogawa; Satoshi Sasaki; Hideki Matsui; Masaharu Nakayama (220-227).
Hedgehog (Hh) signaling critical for development, differentiation, and cell growth is involved in several cancers, including medulloblastoma and basal cell carcinoma. Although antagonism of the smoothened receptor (SMO), which mediates Hh signaling, is an attractive therapeutic target, a drug-resistant mutation in SMO (SMO-D473H) was identified in a clinical trial of the approved drug vismodegib. TAK-441 potently inhibits SMO-D473H, unlike vismodegib and another SMO antagonist, cyclopamine, whereas the differences in binding modes between these antagonists remain unknown. Here we report the biochemical characterization of TAK-441, vismodegib, and cyclopamine by binding kinetics. The association (k on ) and dissociation (k off ) rates were determined by kinetic binding studies using [3H]TAK-441, and dissociation was confirmed by label-free affinity selection-mass spectrometry (AS-MS). In the [3H]TAK-441 competition assay, TAK-441 but not vismodegib and cyclopamine showed time-dependent inhibition. Quantitative kinetic binding analysis revealed that k off of TAK-441 was >10-fold smaller than those of vismodegib and cyclopamine. To further assess the binding mode of antagonists, kinetic binding analysis was performed against SMO-D473H. The D473H mutation affected k off of TAK-441 but not k on . In contrast, only k on was changed by the D473H mutation in the case of vismodegib and cyclopamine. These results suggest that the difference in antagonist efficacy against D473H is associated with the binding mode of antagonists. These findings provide a new insight into the drug action of SMO antagonists and help develop potential therapeutics for drug-resistant mutants.Display Omitted
Keywords: Smoothened receptor; Binding kinetics; TAK-441; Vismodegib; Cyclopamine; D473H;

Tetrandrine suppresses human glioma growth by inhibiting cell survival, proliferation and tumour angiogenesis through attenuating STAT3 phosphorylation by Ji-wei Ma; Yong Zhang; Ru Li; Jie-cheng Ye; Hai-ying Li; Yi-kai Zhang; Zheng-lai Ma; Jin-ying Li; Xue-yun Zhong; Xuesong Yang (228-239).
Tetrandrine (Tet), a bisbenzylisoquinoline alkaloid, has been reported to possess anti-tumour activity. However, its effects on human glioma remain unknown. In this study, we demonstrated that Tet inhibited human glioma cell growth in vitro and in vivo. It has been hypothesised that Tet inhibits glioma growth by affecting glioma cell survival, proliferation and vasculature in and around the xenograft tumour in the chick CAM model and signal transducer and activator of transcription 3 (STAT3) mediated these activities. Therefore, we conducted a detailed analysis of the inhibitory effects of Tet on cell survival using a TUNEL assay and flow cytometric analysis; on cell proliferation based on the expression of proliferating cell nuclear antigen; and on angiogenesis using a CAM anti-angiogenesis assay. We used western blotting to investigate the role of STAT3 on the anti-glioma activities of Tet. The results revealed that Tet inhibited survival and proliferation in human glioma cells, impaired tumour angiogenesis and decreased the expression of phosphorylated STAT3 and its downstream proteins. In sum, our data indicate that STAT3 is involved in Tet-induced the regression of glioma growth by activating tumour cell apoptosis, inhibiting glioma cell proliferation and inhibiting angiogenesis.
Keywords: Tetrandrine; Glioma; Apoptosis; Proliferation; Angiogenesis; CAM; STAT3;

IL-1 receptor antagonist improves morphine and buprenorphine efficacy in a rat neuropathic pain model by Dominika Pilat; Ewelina Rojewska; Agnieszka M. Jurga; Anna Piotrowska; Wioletta Makuch; Barbara Przewlocka; Joanna Mika (240-248).
An interesting research and therapeutic problem is the reduced beneficial efficacy of opioids in the treatment of neuropathic pain. The present study sought to investigate the potential role of IL-1 family members in this phenomenon. We studied the time course of changes in IL-1alpha, IL-1beta, IL-1 receptor type I and IL-1 receptor antagonist mRNA and protein levels experienced by rats after chronic constriction injury (CCI) of the sciatic nerve using qRT-PCR and Western blot analysis. In CCI-exposed rats, spinal levels of IL-1alpha mRNA were slightly downregulated on the 7th day, and protein levels were not changed on the 7th and 14th days. Levels of IL-1 receptor antagonist and IL-1 receptor type I were slightly upregulated in the ipsilateral part of the spinal cord on the 7th and 14th days; however, protein levels were not changed at those time points. Interestingly, we observed that IL-1beta mRNA and protein levels were strongly elevated in the ipsilateral part of the dorsal spinal cord on the 7th and 14th days following CCI. Moreover, in rats exposed to a single intrathecal administration of an IL-1 receptor antagonist (100 ng i.t.) on the 7th and 14th day following CCI, symptoms of neuropathic pain were attenuated, and the analgesic effects of morphine (2.5 µg i.t.) and buprenorphine (2.5 µg i.t.) were enhanced. In summary, restoration of the analgesic activity of morphine and buprenorphine by blockade of IL-1 signaling suggests that increased IL-1beta responses may account for the decreased analgesic efficacy of opioids observed in the treatment of neuropathy.Display Omitted
Keywords: Neuropathic pain; IL-1alpha; IL-1beta; IL-1 receptor type I; IL-1 receptor antagonist;

Involvement of prostaglandin I2 in nitric oxide-induced vasodilation of retinal arterioles in rats by Asami Mori; Ryo Namekawa; Masami Hasebe; Maki Saito; Kenji Sakamoto; Tsutomu Nakahara; Kunio Ishii (249-255).
The soluble guanylyl cyclase/cGMP system plays an important role in the vasodilator response to nitric oxide (NO) in various vascular beds. However, in rat retinal arterioles, the cyclooxygenase-1/cAMP-mediated pathway contributes to the vasodilator effects of NO, although the specific prostanoid involved remains to be elucidated. In the present study, we investigated the role of prostaglandin I2 and its receptor (prostanoid IP receptor) system in NO-induced vasodilation of rat retinal arterioles in vivo. Fundus images were captured using a digital camera that was equipped with a special objective lens. Changes in diameter of retinal arterioles were assessed. The NO donor (±)-(E)-4-ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexenamide (NOR3) increased the diameter of retinal arterioles but decreased systemic blood pressure in a dose-dependent manner. Treatment of rats with indomethacin, a non-selective cyclooxygenase inhibitor, markedly attenuated the retinal vasodilator, but not depressor responses to NOR3. The prostanoid IP receptor antagonist 4,5-dihydro-N-[4-[[4-(1-methylethoxy)phenyl]methyl]phenyl]-1H-imadazol-2-amine (CAY10441), and the prostaglandin I2 synthase inhibitor 9α,11α-azoprosta-5Z,13E-dien-1-oic acid (U-51605), both showed similar preventive effects against the NOR3-induced retinal vasodilator response. Neither CAY10441 nor U-51605 showed any significant effects on the depressor response to NOR3. NOR3 enhanced the release of prostaglandin I2 from cultured human retinal microvascular endothelial cells and the NOR3-induced prostaglandin I2 release was almost completely abolished by the cyclooxygenase-1 inhibitor SC-560, but not by the cyclooxygenase-2 inhibitor NS-398. However, NOR3 did not increase the release of prostaglandin I2 from human intestinal microvascular endothelial cells. These results suggest that NO exerts its dilatory effect via cyclooxygenase-1/prostaglandin I2/prostanoid IP receptor signaling mechanisms in the retinal vasculature.
Keywords: Cyclooxygenase; Nitric oxide; Prostaglandin I2; Prostanoid IP receptor; Retinal blood vessel;

Neuroprotective effects of the monoamine oxidase inhibitor tranylcypromine and its amide derivatives against Aβ(1–42)-induced toxicity by Filippo Caraci; Giuseppe Pappalardo; Livia Basile; Alessandro Giuffrida; Agata Copani; Rita Tosto; Alessandro Sinopoli; Maria Laura Giuffrida; Emanuele Pirrone; Filippo Drago; Rosario Pignatello; Salvatore Guccione (256-263).
Monoamine oxidase (MAO) enzymes play a central role in the pathogenesis of Alzheimer's disease (AD) and MAO inhibitors (MAOIs) are antidepressant drugs currently studied for their neuroprotective properties in neurodegenerative disorders. In the present work MAOIs such as tranylcypromine [trans-(+)-2-phenylcyclopropanamine, TCP] and its amide derivatives, TCP butyramide (TCP-But) and TCP acetamide (TCP-Ac), were tested for their ability to protect cortical neurons challenged with synthetic amyloid-β (Aβ)-(1–42) oligomers (100 nM) for 48 h. TCP significantly prevented Aβ-induced neuronal death in a concentration-dependent fashion and was maximally protective only at 10 µM. TCP-But was maximally protective in mixed neuronal cultures at 1 µM, a lower concentration compared to TCP, whereas the new derivative, TCP-Ac, was more efficacious than TCP and TCP-But and significantly protected cortical neurons against Aβ toxicity at nanomolar concentrations (100 nM).Experiments carried out with the Thioflavin-T (Th-T) fluorescence assay for fibril formation showed that TCP and its amide derivatives influenced the early events of the Aβ aggregation process in a concentration-dependent manner. TCP-Ac was more effective than TCP-But and TCP in slowing down the Aβ(1–42) aggregates formation through a lengthening at the lag phase. In our experimental model co-incubation of Aβ(1–42) oligomers with TCP-Ac was able to almost completely prevent Aβ-induced neurodegeneration. These results suggest that inhibition of Aβ oligomer-mediated aggregation significantly contributes to the overall neuroprotective activity of TCP-Ac and also raise the possibility that TCP, and in particular the new compound TCP-Ac, might represent new pharmacological tools to yield neuroprotection in AD.
Keywords: Amyloid; Neuroprotection; Neurons; Antidepressants; Anti-aggregant activity; MAO;

Central injection of CDP-choline suppresses serum ghrelin levels while increasing serum leptin levels in rats by Sinem Kiyici; Nesrin Filiz Basaran; Sinan Cavun; Vahide Savci (264-270).
In this study we aimed to test central administration of CDP-choline on serum ghrelin, leptin, glucose and corticosterone levels in rats.Intracerebroventricular (i.c.v.) 0.5, 1.0 and 2.0 µmol CDP-choline and saline were administered to male Wistar-Albino rats. For the measurement of serum leptin and ghrelin levels, blood samples were obtained baseline and at 5, 15, 30, 60 and 120 min following i.c.v. CDP-choline injection. Equimolar doses of i.c.v. choline (1.0 µmol) and cytidine (1.0 µmol) were administered and measurements were repeated throughout the second round of the experiment. Atropine (10 µg) and mecamylamine (50 µg) were injected intracerebroventricularly prior to CDP-choline and measurements repeated in the third round of the experiment. After 1 µmol CDP-choline injection, serum ghrelin levels were suppressed significantly at 60 min (P=0.025), whereas serum leptin levels were increased at 60 and 120 min (P=0.012 and P=0.017 respectively). CDP-choline injections also induced a dose- and time-dependent increase in serum glucose and corticosterone levels. The effect of choline on serum leptin and ghrelin levels was similar with CDP-choline while no effect was seen with cytidine. Suppression of serum ghrelin levels was eliminated through mecamylamine pretreatment while a rise in leptin was prevented by both atropine and mecamylamine pretreatments.In conclusion; centrally injected CDP-choline suppressed serum ghrelin levels while increasing serum leptin levels. The observed effects following receptor antagonist treatment suggest that nicotinic receptors play a role in suppression of serum ghrelin levels,whereas nicotinic and muscarinic receptors both play a part in the increase of serum leptin levels.
Keywords: CDP-choline; Ghrelin; Leptin;

Inhibition of spinal ERK1/2–c-JUN signaling pathway counteracts the development of low doses morphine-induced hyperalgesia by Maria Domenica Sanna; Tommaso Mello; Carla Ghelardini; Nicoletta Galeotti (271-277).
Morphine-induced hyperalgesia is a pharmacological phenomenon often hindering its prolonged applications in the clinic. It has been shown that systemic administration of morphine induced a hyperalgesic response at an extremely low dose. Extracellular signal-regulated kinase (ERK) pathway contributes to pain sensitization, and its phosphorylation under pain conditions results in the induction and maintenance of pain hypersensitivity. The present study was designed to determine whether low dose morphine treatment in mice could influence the spinal activity of ERK. The data showed that morphine (1 µg/kg) induced a marked increase in ERK phosphorylation. Intrathecal pre-treatment with a selective mitogen-activated and extracellular signal-regulated kinase (MEK) inhibitor PD98059, attenuated morphine-associated thermal hyperalgesia. Morphine exposure increased phosphorylation of c-JUN, that was prevented by the inhibition of ERK pathway. In addition, double immunofluorescence studies revealed that, p-ERK and p-c-JUN are localized on neurons of the spinal dorsal horn expressing µ receptors. These data suggest that ERK contributes to the morphine-induced hyperalgesia by regulating the activation of c-JUN.
Keywords: Morphine; Hyperalgesia; Extracellular signal-regulated kinase (ERK); c-JUN;

Aggression behaviour induced by oral administration of the Janus-kinase inhibitor tofacitinib, but not oclacitinib, under stressful conditions by Tomoki Fukuyama; Thomas Tschernig; Yulin Qi; Dietrich A. Volmer; Wolfgang Bäumer (278-282).
Janus kinase (JAK) inhibitors have recently been developed for allergic diseases. We focused on the 2 different JAK inhibitors, tofacitinib (selective for JAK3) and oclacitinib (selective for JAK1 and 2), to clarify the mechanism of anti-inflammatory and anti-itching potency of these drugs. In the process of detecting anti-itching potency, we observed that tofacitinib treated mice showed aggression behaviour. The objective of the study reported here was to investigate the aggressive behaviour induced by tofacitinib by using a mouse model of allergic dermatitis and the resident–intruder test. For the allergic dermatitis model, female BALB/c mice were sensitised and challenged topically with toluene-2,4-diisocyanate (TDI). Vehicle, tofacitinib or oclacitinib, was administered orally 30 min before TDI challenge. Scratching, aggression and standing behaviours were monitored in the 60 min period immediately following challenge of TDI. Another group of male BALB/c mice treated with vehicle, tofacitinib or oclacitinib was evaluated in the resident–intruder test and brains were obtained to determine blood brain barrier penetration. In the allergic dermatitis model, a significant increase in aggression and standing behaviour was only obvious in the tofacitinib treatment group. There was no effect in non-sensitised mice, but similar aggression was also induced by tofacitinib in male resident–intruder test. Penetration of blood–brain barrier was observed both in tofacitinib and oclacitinib treated mice. These results suggest that aggression was induced by tofacitinib under some kind of stressful environment. This study indicates a possible role of the JAK-STAT pathway in modulation of aggression behaviour.
Keywords: Janus-Kinase inhibitor; Tofacitinib; Oclacitinib; Aggression; Mice;

The present study was carried out to evaluate the protective effect of different statins on isoproterenol (ISO) induced myocardial necrosis. Atorvastatin, rosuvastatin, fluvastatin, simvastatin and pravastatin (10 mg/kg/day) were administered for 12 weeks. After pretreatment of 12 weeks myocardial necrosis was induced by subsequent injection of ISO (85 mg/kg/day, s.c.) to wistar rats. Serum biochemical parameters like glucose, lipid profile, cardiac markers and transaminases were evaluated. Animals were killed and heart was excised for histopathology and antioxidant study. Statins pretreated rats showed significant protection against ISO induced elevation in serum biochemical parameters and serum level of cardiac marker enzymes and transaminase level as compared to ISO control group. Mild to moderate protection was observed in different statins treated heart in histopathology and TTC stained sections. Result from our study also revealed that statins could efficiently protect against ISO intoxicated myocardial necrosis by impairing membrane bound enzyme integrity and endogenous antioxidant enzyme levels. Amongst all statins used, rosuvastatin and pravastatin were found to have maximum cardio-protective activity against ISO induced myocardial necrosis as compared to other statins.Display Omitted
Keywords: Atorvastatin; Fluvastatin; Isoproterenol; Myocardial necrosis; Pravastatin; Rosuvastatin; Simvastatin;

Neuroprotection of donepezil against morphine-induced apoptosis is mediated through Toll-like receptors by Alireza Shafie; Farshid Moradi; Esmael Izadpanah; Aram Mokarizadeh; Mohammad Raman Moloudi; Mehrnoush Nikzaban; Kambiz Hassanzadeh (292-297).
Previously, we had shown that donepezil provides anti-apoptotic effects associated with the prevention of morphine tolerance to the analgesic effect. In this regard, the present study aimed to evaluate the molecular mechanisms involved in this effect considering the possible role of Toll-like receptor (TLR) 2,4, and the balance between pre-apoptotic and anti-apoptotic Bcl family proteins. To this end, male Wistar rats received daily morphine in combination with either normal saline or donepezil (0.5, 1, or 1.5 mg/kg, ip). The analgesic effect was assessed by the plantar test apparatus. The latency was recorded when the animal responded to the light stimulus. On the 15th day, when no significant difference was observed between morphine and saline groups in terms of analgesia, the frontal cortex and lumbar spinal cord of the animals were dissected. Then, TLR2 and 4, Bcl2, and Bax mRNA fold changes were calculated using Real-time PCR method. The results indicated no significant analgesic effect in the morphine group compared with the saline treated animals after 15 days of injection, while daily co-administration of donepezil with morphine preserved significant analgesia. Moreover, Quantitative PCR showed that morphine significantly increased TLRs and Bax gene expressions and decreased the anti-apoptotic Bcl2. In contrast, donepezil prevented these morphine induced changes in the mentioned gene expressions. Taken together, the results suggest that the neuroprotective effects of donepezil in attenuating morphine-induced tolerance and apoptosis are mediated by preventing morphine-induced changes in TLR2 and 4 gene expressions.
Keywords: Apoptosis; Morphine tolerance; Toll-like receptor;

Maslinic acid promotes synaptogenesis and axon growth via Akt/GSK-3β activation in cerebral ischemia model by Yisong Qian; Menghao Huang; Teng Guan; Lan Chen; Liangxun Cao; Xiao-Jian Han; Longfei Huang; Xuzhen Tang; Yunman Li; Hongbin Sun (298-305).
Maslinic acid, a natural pentacyclic triterpene from Olea europaea plants, possesses neuroprotective effects both in vivo and in vitro. However, the mechanism of its action is not well understood. In this study, we investigated the potential effects of maslinic acid on synaptogenesis and axonal regeneration, as well as the possible signal pathway involved in a cerebral ischemia mouse model. Adult male C57BL/6J mice were subjected to 1 h of cerebral ischemia by middle cerebral artery occlusion (MCAO). Maslinic acid (0.1, 1 and 10 mg/kg) was administered intragastrically 24 h after MCAO once daily for 7 consecutive days. Axonal loss and synaptophysin expression in the ischemic boundary area was evaluated by histological assay. The Akt/GSK-3β signal pathway was determined by western blot analysis. Two Akt inhibitors, LY294002 and MK2206, were used to verify the involvement of Akt/GSK-3β pathway in maslinic acid-mediated neuroprotection. Maslinic acid significantly prevented axonal damage, promoted axonal regeneration and increased synaptophysin expression 7 days after ischemia. In addition, maslinic acid treatment was shown to enhance Akt activity and promote GSK-3β phorsphorylation in stoke mice. The increased neurite outgrowth and synaptophysin expression by maslinic acid treatment was blocked by the Akt inhibitors both in vivo and in vitro.. These findings suggested that maslinic acid promotes synaptogenesis and axonal regeneration by regulating Akt/GSK-3β signaling pathway, which may, in turn, provide neuroprotection.
Keywords: Maslinic acid; Cerebral ischemia; Axon; synaptophysin; Akt; GSK-3β;

Different approaches in the treatment of obstructive pulmonary diseases by Eva Rahman Kabir; Nabila Morshed (306-317).
Advances in drug formulation, inhalation device design and disease management are generating new opportunities for patients suffering from obstructive pulmonary diseases. This article provides a comprehensive review of the different promising pulmonary drug delivery technologies in the treatment of obstructive pulmonary diseases, particularly with regard to the treatment of asthma and chronic pulmonary diseases (COPD), which are increasing day by day due to increasing environmental pollution and its harmful and toxic contaminants. In the recent years, a better knowledge has been gained regarding the mechanism of action of glucocorticoids and how they suppress the chronic inflammation. New etiology has been brought into light regarding the inactivity of glucocorticoids in some patients having asthma and COPDs even though the inflammatory genes are triggered by similar molecules in both the diseases. This new knowledge has given a new platform to improve glucocorticoids and their resistance also how other combination therapy can be used for these diseases. It has also led to the quest for improving and developing other alternatives such as anti-leukotriene agents, muscarinic inhibitors, combination therapy, as well as biologic immune-modulators in the treatment of the different pulmonary diseases. Several new combinations of glucocorticoids are available in the global market for the use in pulmonary diseases especially asthma although their availability fluctuates between continents. There has been several studies done regarding the variation of effectiveness of the different inhaled glucocorticoids and hence it is important to take into consideration the different delivery systems and the methods which are used to treat the patients.
Keywords: Glucocorticoids; Biologic immunomodulators; Mechanism of action; Obstructive pulmonary disease treatment;

Effects of ethanol on RhoA/Rho-kinase-mediated calcium sensitization in mouse lung parenchymal tissue by Fatma Aydinoglu; Olcay Ergurhan Kiroglu; Erhan Astarci; Ebru Balli; Nuran Ogulener (318-327).
Calcium sensitization by the RhoA/Rho-kinase (ROCK) pathway contributes to the contraction in smooth muscle. Contractile stimuli can sensitize myosin to Ca2+ by activating RhoA/Rho-kinase that inhibits myosin light chain phosphatase activity. The present study was aimed at investigating the possible involvement of RhoA/Rho-kinase pathway in contractile responses to agonist (phenylephrine) and depolarizing (KCl) of mouse lung parenchymal tissues. Also, we investigated the effect of ethanol on RhoA/Rho-kinase pathway. Phenylephrine (10−8–10−4  M) and KCl (10–80 mM) induced sustained contractions in parenchymal strips. Ethanol significantly attenuated the contractions to phenylephrine and KCl. The Rho-kinase inhibitors fasudil (5×10−5  M) and Y-27632 (5×10 5  M) inhibited contractions to in both control and ethanol-treated parenchymal strips. In addition, the relaxations induced by fasudil (10 4  M) and Y-27632 (5×10−4  M) on parenchymal strips contracted by phenylephrine but not KCl was decreased in ethanol-treatment group. Also, RhoA, ROCK1 and ROCK2 expressions were detected in mouse lung parenchymal tissue. In ethanol-treated group, expression of RhoA and ROCK1 but not ROCK2 decreased compared to control. Furthermore, ethanol causes apoptotic changes in alveolar type I epithelial cells of parenchymal tissue. These results suggest that RhoA/Rho-kinase signaling pathway plays an important role in phenylephrine- and KCl-induced Ca2 + sensitization in mouse lung parenchymal tissue. Also, ethanol may be decrease phenylephrine- and KCl-induced contraction due to lowering the RhoA/Rho-kinase-mediated Ca2+-sensitizing by inhibiting RhoA/Rho-kinase pathway in parenchymal tissue. These results may be lead to important insights into the mechanisms of lung diseases due to alcohol consumption.
Keywords: RhoA/Rho-kinase; Contraction; Ethanol; Fasudil; Y-27632;

The present study addresses the causal relationship between induction of endo/sarcoplasmic reticulum stress and dysregulation of calcium transport, while examining whether the most widely-used experimental endo/sarcoplasmic reticulum stressors can be considered appropriate for elucidating underlying cellular mechanisms involved during the progression of the unfolded protein response in vascular smooth muscle cells. Brefeldin A is most commonly cited as inducing the stress response through an accumulation of unfolded proteins in the lumen as a result of a blockage of protein transport from the endo/sarcoplasmic reticulum to the Golgi apparatus. We investigated the effects of Brefeldin A on cellular calcium regulation during the the unfolded protein response in cultured rat vascular smooth muscle cells. Acute exposure of cells to Brefeldin A caused a small transient increase in cytoplasmic calcium, which did not cause a significant decrease in endo/sarcoplasmic reticulum calcium content. However, over the time course of 0–12 h post-treatment with Brefeldin A, we observed that the endo/sarcoplasmic reticulum of vascular smooth muscle cells exhibited an approximate fifty percent decrease in calcium concentration after the first hour of exposure, which is maintained over the next eleven hours, whereas concentrations of unfolded protein response markers only began to increase significantly around nine to twelve hours post-treatment. We have concluded that the endo/sarcoplasmic reticulum calcium drop, which up to now, has been considered as a characteristic of the late onset of cellular stress response, occurs prior to the initiation of the unfolded protein response, rather than as a result of its many corrective pathways.
Keywords: Unfolded protein response; ER stress; Calcium; Brefeldin A; Vascular smooth muscle cells;

Anti-tumor effect investigation of obtustatin and crude Macrovipera lebetina obtusa venom in S-180 sarcoma bearing mice by Narine A. Ghazaryan; Lusine A. Ghulikyan; Arsen V. Kishmiryan; Gayane R. Kirakosyan; Ofik H. Nazaryan; Tigran H. Ghevondyan; Naira A. Zakaryan; Naira M. Ayvazyan (340-345).
Over the last few decades, research on snake venom toxins has provided not only new tools to decipher molecular details of various physiological processes, but also inspiration to design and develop a number of therapeutic agents. Isolated from the venom of Macrovipera lebetina obutusa (MLO), obtustatin represents the shortest known snake venom monomeric disintegrin specific inhibitor of α1β1 integrin. This low molecular weight peptide revealed a potent therapeutic effect on melanoma progression. Its oncostatic effect was related to the inhibition of angiogenesis. The aim of the proposed investigation was to study the influence of obtustatin and crude MLO venom on the S-180 sarcoma growth in vitro and in vivo. A S-180 sarcoma bearing mouse model, histological examination, DNA retardation assay were utilized to investigate the anti-tumor effects of MLO and obtustatin. In addition, some biochemical tests (chemiluminescence-ChL, TBA-test) were applied to elucidate the influence of obtustatin and crude MLO venom on the S-180 sarcoma. The size of tumor was significantly inhibited by MLO venom and obtustatin with the inhibitory rate of 50% and 33% at the doses of 10 µg/mouse and 1 mg/kg/day respectively. Both ChL and MDA decrease in the two treated groups. Both obtustatin and MLO venom have an anticancer activity and might be candidates for the treatment of malignant sarcoma. All our results have shown that both obtustatin and MLO venom have an anticancer activity and might be candidates for the treatment of malignant sarcoma.
Keywords: MLO venom; Obtustatin; S-180 sarcoma; DNA;

The pro-healing effect of exendin-4 on wounds produced by abrasion in normoglycemic mice by Stefano Bacci; Annunziatina Laurino; Maria Elena Manni; Elisa Landucci; Claudia Musilli; Gaetano De Siena; Alessandra Mocali; Laura Raimondi (346-352).
Experimental evidence suggested that Exendin-4 (Exe4), an agonist at glucagon like receptor-1 (GLP-1R), promoted tissue regeneration. We aimed to verify the effect of Exe4, in the absence or in the presence of Exendin-4(9-39), an antagonist at GLP-1R, on the healing of abraded skin.Two wounds (approximately 1.1×1.1 cm2; namely “upper” and “lower” in respect of the head) were produced by abrasion on the back of 12 mice, which were then randomly assigned to receive an intradermal injection (20 μl) ofGroup 1: saline (NT) or Exe4 (62 ng) in the upper and lower wound respectively;Group 2: Exendin-4(9-39) (70 ng) in the upper and Exendin-4(9-39) (70 ng) and, after 15 min, Exe4 (62 ng) in the lower wound.Wounds were measured at the time of abrasion (T0) and 144 h (T3) afterward taking pictures with a ruler and by using a software. The inflammatory cell infiltrate, fibroblasts/myofibroblasts, endothelial cells and GLP-1R expression, were each labeled by immunofluorescence in each wound, pERK1/2 was evaluated by Western-blot in wound lysates.At T3, the percentage of healing surface was 53% and 92% for NT and Exe4 wounds respectively and 68% and 79% for those treated with Exendin-4(9-39) and Exendin-4(9-39)+Exe4 respectively. Exe4, but not Exendin-4(9-39) induced quantitative increase in fibroblasts/myofibroblasts and vessel density when compared to NT wounds. This increase was not evident in wounds treated with Exendin-4(9-39)+Exe4.Exe4 promotes wound healing opening to the possible dermatological use of this incretin analogue.
Keywords: Wound healing; Exendin-4; Exendin-4(9-39); Angiogenesis; Glucagon-like type 1 receptor;

Study of the mechanisms of apoptosis in tumor cells is an important field of tumor therapy and cancer molecular biology. We recently established that III-10, a new flavonoid with a pyrrolidinyl and a benzyl group substitution, exerted its anti-tumor effect via inducing differentiation of human U937 leukemia cells. In this study, we demonstrated that III-10 induced cell apoptosis in human hepatocellular carcinoma cells. The activation of caspase-3, caspase-9, and the increased expression ratio of Bax/Bcl-2 were detected in III-10-induced apoptosis. Z-VAD-FMK, a pan-caspase inhibitor, partly attenuated the apoptotic induction of III-10 on both HepG2 and BEL-7402 cells. Furthermore, the increase of intracellular reactive oxygen species levels and the reduction of mitochondria ΔΨm were also observed in BEL-7402 and HepG2 cells after the treatment of III-10. Pretreatment with NAC, a reactive oxygen species production inhibitor, partly attenuated the apoptosis induced by III-10 via blocking the reactive oxygen species generation. Our data also showed that III-10 induced the release of cytochrome c and AIF to cytosol followed after the reactive oxygen species accumulation. Moreover, the GSH levels and ATP generation were both inhibited after III-10 treatment. Besides, the MAPK, the downstream effect of reactive oxygen species accumulation including JNK could be activated by III-10, as well as the inactivation of ERK. Collectively, the generation of reactive oxygen species might play an crucial role in III-10-induced mitochondrial apoptosis pathway, provided more stubborn evidence for III-10 as a potent anticancer therapeutic candidate.
Keywords: Apoptosis; Reactive oxygen species; Mitochondria; MMP; MAPK;

The relaxant effect of 8(17),12E,14-labdatrien-18-oic acid (LBD) was investigated on isolated aortic rings and compared with forskolin (FSK), a standard and potent activator of adenylyl cyclase (AC) with relaxing effect. The presence of potassium channel blockers, such as glibenclamide (ATP-blocker), apamin (SKCa-blocker), charybdotoxin (BKCa-blocker) did not significantly affect either the LBD or FSK concentration-response curves. However, in the presence of 4-aminopyridine (KV-blocker), the relaxant effect for both diterpenes was significantly attenuated, with reduction of its relative potencies. Moreover, the relaxation induced by 8-Br-cAMP, an analog of cAMP, was also significantly attenuated in the same conditions, i.e., in the presence of 4-aminopyridine. The presence of aminophylline, a nonselective phosphodiesterase inhibitor, caused a significant increasing in the potency for both LBD and FSK. On the other hand, the presence of Rp-cAMPS, a selective PKA-inhibitor, significantly attenuated the relaxant effect of LBD. In this work, in the same experimental conditions, both labdane-type diterpenes presented remarkably similar results; FSK, however, presented a higher potency (100-fold) than LBD. Thus, the hypothesis that LBD could be a novel AC-activator emerged. To assess that hypothesis, computational molecular docking studies were performed. Crystallographic structure of adenylyl cyclase/forskolin complex (1AB8) was obtained from RSCB Protein Data Bank and used to compare the modes of interaction of the native ligand and LBD. The computational data shows many similarities between LBD and FSK concerning the interaction with the regulatory site of AC. Taken together, the results presented here pointed to LBD as a novel AC-activator.Display Omitted
Keywords: Adenylyl cyclase; Forskolin; Diterpenes; Potassium channels; Smooth muscle; Molecular docking;

Rethinking tamoxifen in the management of melanoma: New answers for an old question by Mariana P.C. Ribeiro; Armanda E. Santos; José B.A. Custódio (372-378).
The use of the antiestrogen tamoxifen in melanoma therapy is controversial due to the unsuccessful outcomes and a still rather unclarified mechanism of action. It seemed that the days of tamoxifen in malignant melanoma therapy were close to an end, but new evidence may challenge this fate. On one hand, it is now believed that metabolism is a major determinant of tamoxifen clinical outcomes in breast cancer patients, which is a variable that has yet to be tested in melanoma patients, since the tamoxifen active metabolite endoxifen demonstrated superior cytostatic activity over the parent drug in melanoma cells; on the other hand, new evidence has emerged regarding estrogen-mediated signaling in melanoma cells, including the methylation of the estrogen receptor-α gene promoter and the expression of the G protein coupled estrogen receptor. The expression of estrogen receptor-α and G protein coupled estrogen receptor, as well as the cytochrome P450 (CYP) 2D6 genotype, may be used as predictive biomarkers to select the patients that may respond to antiestrogens based on specific traits of their tumors. This review focused on these new evidences and how they may contribute to shed new light on this long-lasting controversy, as well as their possible implications for future investigations.
Keywords: Melanoma; Tamoxifen metabolism; Endoxifen; Estrogen receptor α; G protein coupled estrogen receptor;

The link between mitochondrial complex I and brain-derived neurotrophic factor in SH-SY5Y cells – The potential of JNX1001 as a therapeutic agent by Helena K. Kim; Karina M. Mendonça; Patrick A. Howson; Jonathan M. Brotchie; Ana C. Andreazza (379-384).
Mitochondrial complex I, which is the first member of the electron transport chain responsible for producing ATP, can produce reactive oxygen species and oxidative stress when it becomes dysfunctional. Complex I dysfunction and oxidative stress are strongly implicated in bipolar disorder (BD), a debilitating psychiatric disease, as is decreased levels of brain derived neurotrophic factor (BDNF) found in patients with BD, which is related to complex I activity. JNX1001, a clinical trial ready brain penetrant sapogenin, increases BDNF levels in animal models. Hence, we aimed to examine if JNX1001 can prevent complex I dysfunction-induced alterations produced by rotenone treatment in human neuroblastoma cells (SH-SY5Y). Complex I dysfunction decreased cell viability and increased protein carbonylation and nitration, confirming previous findings. Complex I dysfunction also decreased intracellular and extracellular BDNF levels. JNX1001 pre-treatment prevented complex I dysfunction-induced protein carbonylation and nitration and improved cell viability at concentrations of 30 nM and 300 nM, but more robustly at 300 nM. JNX1001 was also able to prevent decreased intracellular and extracellular BDNF levels, where it produced a ten-fold increase in intracellular BDNF levels at a concentration of 300 nM. While further studies are required to examine the neuroprotective ability of JNX1001 against alterations produced by complex I defect in more complex systems, such as in animal models, the findings of this study demonstrate the potential of JNX1001 to be used as a therapeutic agent to protect against complex I dysfunction-induced alterations that may be highly relevant to BD.
Keywords: JNX1001; Mitochondrial complex I; BDNF; Oxidative stress; Carbonylation; Nitration;

Atrial chronotropic reactivity to catecholamines in neonatal rats: Contribution of β-adrenoceptor subtypes by Elizângela S. Oliveira; Ana H. Pereira; Alisson C. Cardoso; Kleber G. Franchini; José W.M. Bassani; Rosana A. Bassani (385-394).
Although increase in heart rate is a crucial determinant for enhancement of cardiac output in the neonate, information on the chronotropic reactivity to catecholamines during postnatal development is scarce. The present study was aimed at investigating the role of β-adrenoceptor subtypes and catecholamine removal mechanisms in the adrenergic chronotropic response during the early post-natal period. Right atria isolated from immature (0–21 day old) and adult (4–6 month old) rats were used for determination of the responsiveness to agonists and quantitation of the transcripts of proteins involved in β-adrenergic signaling. The main results were: (a) the maximum response (R max) to norepinephrine increased with age, whereas sensitivity decreased; (b) age-dependent differences in sensitivity to norepinephrine were abolished by inhibition of the neuronal norepinephrine transporter; (c) R max to isoproterenol was similar in immature and adult atria, and depressed only in the former by β2-adrenoceptor blockade with ICI118,551; (d) neonatal atria showed greater β2-adrenoceptor mRNA levels, and more prominent positive chronotropic response to the β2- and β3-adrenoceptor agonists zinterol and YM178, respectively (nanomolar range); (e) in atria of immature rats, transcript levels of the extraneuronal monoamine transporter were lower, and its inhibition did not affect sensitivity to isoproterenol; and (f) reactivity to forskolin and 3-isobutyl-1-methylxanthine was not affected by age. The increased β2- and β3-adrenoceptor participation in the adrenergic chronotropic response, in addition to weaker catecholamine removal, may compensate for the immature cardiac innervation and the apparently reduced efficiency of β1-adrenoceptor signaling in the neonate, increasing the responsiveness to endogenous and exogenous β2-adrenoceptor agonists.
Keywords: Right atrium; Chronotropic activity; β-Adrenoceptor subtypes; Catecholamines; Post-natal development;

Differential modulation of Nav1.7 and Nav1.8 channels by antidepressant drugs by Olivier Thériault; Hugo Poulin; Jean-Martin Beaulieu; Mohamed Chahine (395-403).
Antidepressant drugs of the SSRI family are used as a third-line treatment for neuropathic pain. In contrast MAOi antidepressants, that also increase extracellular serotonin bioavailability have little or no effects on this condition. In addition to their action of the serotonin transporter, some SSRI have been shown to inhibit voltage gated sodium channels. Here we investigated the potential inhibition of SSRIs and MAOi antidepressants on Nav1.7 or Nav1.8, which are expressed in sensory neurons and play an important role in pain sensation.We used the whole-cell patch-clamp technique on HEK293 cells expressing either Nav1.7 or Nav1.8, and evaluated the effects of the SSRIs fluoxetine, paroxetine, and citalopram as well as one MAOi antidepressants on the electrophysiological properties of the Na+ channels.Paroxetine exhibited the greatest affinity for Na+ channels. In ascending order of affinity for Nav1.7 were paroxetine (IC50=10 µM), followed by fluoxetine (IC50=66 µM), then citalopram (IC50=174 µM). In ascending order of affinity for Nav1.8 were paroxetine (IC50=9 µM), followed by fluoxetine (IC50=49 µM), then citalopram (IC50=100 µM). Paroxetine and fluoxetine accelerated the onset of slow-inactivation and delayed the time-course of recovery from inactivation for both channels. Paroxetine and fluoxetine also had a prominent effect on the frequency-dependent inhibition, with a greater effect on Nav1.7. In contrast to SSRIs, MAOi did not affect Na+ channels currents.These results suggest that, in certain conditions, the analgesic effect of SSRIs may in part be due to their interactions with Na+ channels.
Keywords: Sodium channels; Fluoxetine; Paroxetine; Citalopram; Antidepressant; SSRI; Nav1.7;

Bryostatin extends tPA time window to 6 h following middle cerebral artery occlusion in aged female rats by Zhenjun Tan; Brandon P. Lucke-Wold; Aric F. Logsdon; Ryan C. Turner; Cong Tan; Xinlan Li; Jarin Hongpaison; Daniel L. Alkon; James W. Simpkins; Charles L. Rosen; Jason D. Huber (404-412).
Blood–brain barrier (BBB) disruption and hemorrhagic transformation (HT) following ischemic/reperfusion injury contributes to post-stroke morbidity and mortality. Bryostatin, a potent protein kinase C (PKC) modulator, has shown promise in treating neurological injury. In the present study, we tested the hypothesis that administration of bryostatin would reduce BBB disruption and HT following acute ischemic stroke; thus, prolonging the time window for administering recombinant tissue plasminogen activator (r-tPA). Acute cerebral ischemia was produced by reversible occlusion of the right middle cerebral artery (MCAO) in 18–20-month-old female rats using an autologous blood clot with delayed r-tPA reperfusion. Bryostatin (or vehicle) was administered at 2 h post-MCAO and r-tPA was administered at 6 h post-MCAO. Functional assessment, lesion volume, and hemispheric swelling measurements were performed at 24 h post-MCAO. Assessment of BBB permeability, measurement of hemoglobin, assessment of matrix metalloproteinase (MMP) levels by gel zymography, and measurement of PKCε, PKCα, PKCδ expression by western blot were conducted at 24 h post-MCAO. Rats treated with bryostatin prior to r-tPA administration had decreased mortality and hemispheric swelling when compared with rats treated with r-tPA alone. Administration of bryostatin also limited BBB disruption and HT and down-regulated MMP-9 expression while up-regulating PKCε expression at 24 h post-MCAO. Bryostatin administration ameliorates BBB disruption and reduces the risk of HT by down-regulating MMP-9 activation and up-regulating PKCε. In this proof-of-concept study, bryostatin treatment lengthened the time-to-treatment window and enhanced the efficacy and safety of thrombolytic therapy.
Keywords: Bryostatin; Blood–brain barrier; Hemorrhagic transformation; Protein kinase C; MMP-9;

Transforming growth factor-β (TGF-β) has both tumor suppressive and oncogenic activities. Autocrine TGF-β signaling supports tumor survival and growth in certain types of cancer, and the TGF-β signaling pathway is a potential therapeutic target for these types of cancer. TGF-β induces p21 expression, and p21 is considered as an oncogene as well as a tumor suppressor, due to its anti-apoptotic activity. Thus, we hypothesized that autocrine TGF-β signaling maintains the expression of p21 at levels that can support cell growth. To verify this hypothesis, we sought to examine p21 expression and cell growth in various cancer cells following the inhibition of autocrine TGF-β signaling using siRNAs targeting TGF-β signaling components and SB431542, a TGF-β receptor inhibitor. Results from the present study show that p21 expression and cell growth were reduced by knockdown of TGF-β signaling components using siRNA in MDA-MB231 and A549 cells. Cell growth was also reduced in p21 siRNA-transfected cells. Downregulation of p21 expression induced cellular senescence in MDA-MB231 cells but did not induce apoptosis in both cells. These data suggest that autocrine TGF-β signaling is required to sustain p21 levels for positive regulation of cell cycle. On the other hand, treatment with SB431542 up-regulated p21 expression while inhibiting cell growth. The TGF-β signaling pathway was not associated with the SB431542-mediated induction of p21 expression. Specificity protein 1 (Sp1) was downregulated by treatment with SB431542, and p21 expression was increased by Sp1 knockdown. These findings suggest that downregulation of Sp1 expression is responsible for SB43154-induced p21 expression.
Keywords: TGF-β; SB431542; p21; Specificity protein 1 (Sp1);

Antinociceptive properties of selective MT2 melatonin receptor partial agonists by Martha López-Canul; Stefano Comai; Sergio Domínguez-López; Vinicio Granados-Soto; Gabriella Gobbi (424-432).
Melatonin is a neurohormone involved in the regulation of both acute and chronic pain whose mechanism is still not completely understood. We have recently demonstrated that selective MT2 melatonin receptor partial agonists have antiallodynic properties in animal models of chronic neuropathic pain by modulating ON/OFF cells of the descending antinociceptive system. Here, we examined the antinociceptive properties of the selective MT2 melatonin receptor partial agonists N-{2-[(3-methoxyphenyl)phenylamino]ethyl}acetamide (UCM765) and N-{2-[(3-bromophenyl)-(4-fluorophenyl)amino]ethyl}acetamide (UCM924) in two animal models of acute and inflammatory pain: the hot-plate and formalin tests. UCM765 and UCM924 (5–40 mg/kg, s.c.) dose-dependently increased the temperature of the first hind paw lick in the hot-plate test, and decreased the total time spent licking the injected hind paw in the formalin test. Antinociceptive effects of UCM765 and UCM924 were maximal at the dose of 20 mg/kg. At this dose, the effects of UCM765 and UCM924 were similar to those produced by 200 mg/kg acetaminophen in the hot-plate test, and by 3 mg/kg ketorolac or 150 mg/kg MLT in the formalin test. Notably, antinociceptive effects of the two MT2 partial agonists were blocked by the pre-treatment with the MT2 antagonist 4-phenyl-2-propionamidotetralin (4P-PDOT, 10 mg/kg) in both paradigms. These results demonstrate the antinociceptive properties of UCM765 and UCM924 in acute and inflammatory pain models and corroborate the concept that MT2 melatonin receptor may be a novel target for analgesic drug development.
Keywords: Acute pain; Antinociception; Formalin test; Hot-plate test; Melatonin; MT2 receptor partial agonists;

Barnidipine ameliorates the vascular and renal injury in l-NAME-induced hypertensive rats by F. Ilkay Alp Yildirim; Deniz Eker Kizilay; Bülent Ergin; Özlem Balci Ekmekçi; Gökçe Topal; Mine Kucur; Cihan Demirci Tansel; B. Sönmez Uydeş Doğan (433-442).
The present study was aimed to investigate the influence of Barnidipine treatment on early stage hypertension by determining the function and morphology of the mesenteric and renal arteries as well as the kidney in Nω-Nitro-l-Arginine Methyl Ester (l-NAME)-induced hypertensive rats. Barnidipine (3 mg/kg/day p.o) was applied to rats after 2 weeks of l-NAME (60 mg/kg/day) administration, and continued for the next 3 weeks concomitantly with l-NAME. The systolic blood pressure (SBP) of rats was determined to decrease significantly in Barnidipine treated hypertensive group when compared to that of rats received l-NAME alone. Myograph studies demonstrated that the contractile reactivity to noradrenaline were significantly reduced in both of the resistance arteries while endothelium-dependent relaxations to acethylcholine were significantly diminished particularly in the mesenteric arteries of l-NAME-induced hypertensive rats. The impaired contractile and endothelial responses were completely restored by concomitant treatment of Barnidipine with l-NAME. Histopathological examinations verified structural alterations in the arteries as well as the kidney. Moreover, a decrease in endothelial nitric oxide synthase (eNOS) expression was presented both in the arteries and kidney of hypertensive rats which were increased following Barnidipine treatment. Elevated plasma levels of malondialdehyde (MDA) and myeloperoxidase (MPO) were also reduced in Barnidipine treated hypertensive rats. In conclusion, besides to its efficacy in reducing the elevated SBP, amelioration of vascular function, modulation of arterial and renal eNOS expressions as well as reduction of the plasma levels of oxidative and inflammatory biomarkers are possible supportive mechanisms mediating the favorable implications of Barnidipine in l-NAME-induced hypertension model.
Keywords: Barnidipine; l-NAME-induced hypertension; Mesenteric artery; Renal artery; Kidney;

Anti-inflammatory effects of farrerol on IL-1β-stimulated human osteoarthritis chondrocytes by Hongfei Zhang; Jiapeng Yan; Yuesheng Zhuang; Guiquan Han (443-447).
The present study aimed to investigate the anti-inflammatory effects and the underlying molecular mechanism of farrerol on IL-1β-stimulated human osteoarthritis chondrocytes. Chondrocytes were pretreated with farrerol 1 h before IL-1β stimulation. The effects of farrerol on NO and PGE2 production were tested by Griess reagent and ELISA. The effects of farrerol on COX-2, iNOS, Akt, phosphorylated Akt, and NF-κB activation were measured by western blot analysis. The results showed that farrerol remarkably inhibited IL-1β-induced NO and PGE2 production, as well as COX-2 and iNOS expression. Farrerol also inhibited IL-1β-induced NF-κB activation. Furthermore, farrerol significantly inhibited IL-1β-induced phosphorylation of PI3K and Akt. In conclusion, these results indicated that farrerol inhibited IL-1β-induced inflammatory responses in osteoarthritis chondrocytes by blocking PI3K/Akt/NF-κB signaling pathway.
Keywords: Farrerol; Osteoarthritis chondrocyte; IL-1β; NF-κB; PI3K;

Berberine has proven protective effects on diabetic nephropathy, but the mechanism for its effects has not been comprehensively established. Hence, we aimed to explore the renoprotective mechanism of berberine on the accumulation of extracellular matrix, alterations of its major components and corresponding changes in the regulatory system, including the matrix metalloproteinases/tissue inhibitor of matrix metalloproteinases (MMPs/TIMPs) system, in diabetic nephropathy rats. In the experiments, diabetic nephropathy rats were treated with berberine (0, 50, 100, 200 mg/kg) respectively. The protein levels of transforming growth factor-β1 were then detected by Western blot, while fibronectin and type IV collagen levels were assessed using immunohistochemistry. Changes in the MMP2/9 and TIMP1/2 levels were detected using two forms simultaneously. In addition, we also measured the characteristics and biochemical indicators of the diabetic nephropathy rats. The results showed that berberine could ameliorate the fasting blood glucose, and the majority of biochemical and renal function parameters, but did not have an effect on body weight. Immunohistochemistry and Western blot examination revealed a significant increase in the MMP9 and TIMP1/2 levels, with an obvious decrease in MMP2 expression in the diabetic nephropathy rats. Berberine (100 and 200 mg/kg) could significantly improve the abnormal changes in the MMPs/TIMPs system. Meanwhile, reductions in the transforming growth factor-β1, fibronectin and type IV collagen expression levels were observed in the berberine treatment groups. Therefore, the renoprotective effects of berberine on diabetic nephropathy might be associated with changes in the extracellular matrix through the regulation of the MMPs/TIMPs system in the rat kidney.Display Omitted
Keywords: Diabetic nephropathy; Berberine; MMPs/TIMPs system; ECM; Renal fibrosis;

Induction and antagonism of pica induced by teriparatide in rats by Kouichi Yamamoto; Naoto Kato; Yukihiro Isogai; Tatsuhiko Kuroda; Takayuki Ishida; Atsushi Yamatodani (457-462).
Intermittent subcutaneous injection of teriparatide, an active fragment of human parathyroid hormone, is clinically used for the treatment of osteoporosis. Patients suffer from nausea, which is one of the side effects teriparatide induces; however, the etiology of teriparatide-induced nausea remains unknown. We have reported pica, kaolin ingestion behavior, can be used as an assessment of nausea-related response in rats. In this study, we investigated the characteristics of teriparatide-induced pica and the abilities of anti-emetic drugs to inhibit teriparatide-induced pica. Male and female adolescent (4-week-old), young (8-week-old), and adult (30-week-old) naive rats, and ovariectomized (OVX: 17-week-old) and sham-operated (17-week-old) rats subcutaneously received teriparatide (0.4 mg/kg, n=4), and their kaolin and food intakes were monitored for 24 h after the injection. Among the tested rats, we found that OVX rats, rather than male, female, and sham-operated rats, showed marked teriparatide-induced pica (0 mg/kg: 0.17±0.07 g, 0.4 mg/kg: 6.18±0.91 g). Teriparatide-induced pica in OVX rats was inhibited by intraperitoneal pretreatment with serotonin 5-HT3 (granisetron 0.5 mg/kg), dopamine D2 (prochlorperazine 0.5 mg/kg), neurokinin NK1 (fosaprepitant 1 mg/kg), and histamine H1 (diphenhydramine 10 mg/kg) receptor antagonists to 70%, 11%, 19%, and 59% of that in vehicle-treated control, respectively. These results suggest that teriparatide-induced pica in OVX rats has the potential to reflect teriparatide-induced nausea; 5-HT3, D2, NK1, and H1 receptor activation is involved in the development of this behavior; antagonists of these receptors have the potential to be medical candidates used as treatments for teriparatide-induced nausea in human patients.
Keywords: Anti-emetic drugs; Nausea; Ovariectomized rats; Pica; Teriparatide;

Bidirectional effects of hydrogen sulfide via ATP-sensitive K+ channels and transient receptor potential A1 channels in RIN14B cells by Ayako Ujike; Ken-ichi Otsuguro; Ryo Miyamoto; Soichiro Yamaguchi; Shigeo Ito (463-470).
Hydrogen sulfide (H2S) reportedly acts as a gasotransmitter because it mediates various cellular responses through several ion channels including ATP-sensitive K+ (KATP) channels and transient receptor potential (TRP) A1 channels. H2S can activate both KATP and TRPA1 channels at a similar concentration range. In a single cell expressing both channels, however, it remains unknown what happens when both channels are simultaneously activated by H2S. In this study, we examined the effects of H2S on RIN14B cells that express both KATP and TRPA1 channels. RIN14B cells showed several intracellular Ca2+ concentration ([Ca2+]i) responses to NaHS (300 µM), an H2S donor, i.e., inhibition of spontaneous Ca2+ oscillations (37%), inhibition followed by [Ca2+]i increase (24%), and a rapid increase in [Ca2+]i (25%). KATP channel blockers, glibenclamide or tolbutamide, abolished any inhibitory effects of NaHS and enhanced NaHS-mediated [Ca2+]i increases, which were inhibited by extracellular Ca2+ removal, HC030031 (a TRPA1 antagonist), and disulfide bond-reducing agents. NaHS induced 5-hydroxytryptamine (5-HT) release from RIN14B cells, which was also inhibited by TRPA1 antagonists. These results indicate that H2S has both inhibitory and excitatory effects by opening KATP and TRPA1 channels, respectively, in RIN14B cells, suggesting potential bidirectional modulation of secretory functions.
Keywords: Hydrogen sulfide; Ca2+ signal; TRPA1; KATP channels; RIN14B cells;

L-cysteine/d,L-homocysteine-regulated ileum motility via system L and B°,+ transporter: Modification by inhibitors of hydrogen sulfide synthesis and dietary treatments by Satoshi Yamane; Ryouya Nomura; Madoka Yanagihara; Hiroyuki Nakamura; Hiromichi Fujino; Kenjiro Matsumoto; Syunji Horie; Toshihiko Murayama (471-479).
Previous studies including ours demonstrated that l-cysteine treatments decreased motility in gastrointestinal tissues including the ileum via hydrogen sulfide (H2S), which is formed from sulfur-containing amino acids such as l-cysteine and l-homocysteine. However, the amino acid transport systems involved in l-cysteine/l-homocysteine-induced responses have not yet been elucidated in detail; therefore, we investigated these systems pharmacologically by measuring electrical stimulation (ES)-induced contractions with amino acids in mouse ileum preparations. The treatments with l-cysteine and d,l-homocysteine inhibited ES-induced contractions in ileum preparations from fasted mice, and these responses were decreased by the treatment with 2-aminobicyclo[2.2.1]heptane-2-carboxylate (BCH), an inhibitor of systems L and B°,+. The results obtained using ileum preparations and a model cell line (PC12 cells) with various amino acids and BCH showed that not only l-cysteine, but also aminooxyacetic acid and d,l-propargylglycine, which act as H2S synthesis inhibitors, appeared to be taken up by these preparations/cells in L and B°,+ system-dependent manners. The l-cysteine and d,l-homocysteine responses were delayed and abolished, respectively, in ileum preparations from fed mice. Our results suggested that the regulation of ileum motility by l-cysteine and d,l-homocysteine was dependent on BCH-sensitive systems, and varied depending on feeding in mice. Therefore, the effects of aminooxyacetic acid and d,l-propargylglycine on transport systems need to be considered in pharmacological analyses.
Keywords: l-Cysteine; System L; Contractility; Mouse ileum; Hydrogen sulfide;

Inhibition of cytochrome P450 2J2 by tanshinone IIA induces apoptotic cell death in hepatocellular carcinoma HepG2 cells by Yu Jin Jeon; Joong Sun Kim; Geun Hye Hwang; Zhexue Wu; Ho Jae Han; Soo Hyun Park; Woochul Chang; Lark Kyun Kim; You-Mie Lee; Kwang-Hyeon Liu; Min Young Lee (480-488).
Cytochrome P450 2J2 (CYP2J2) is highly expressed in human tumors and carcinoma cell lines, and has been implicated in the pathogenesis of human cancers. The aim of this study was to identify a compound that could inhibit the activity of CYP2J2, and to examine its anticancer activity. To identify CYP2J2 inhibitors, 10 terpenoids obtained from plants were screened using astemizole as a CYP2J2 probe substrate in human liver microsomes (HLMs). Of these, tanshinone IIA dose-dependently and non-competitively inhibited CYP2J2-mediated astemizole O-demethylation activity. Tanshinone IIA significantly decreased viability of human hepatoma HepG2 cells and SiHa cervical cancer cells; however, it was not cytotoxic against mouse hepatocytes. Furthermore, treatment of cells with tanshinone IIA significantly increased apoptotic cell death rate, as shown by the increase in Annexin V-stained cell populations, Bcl-2 associated X protein (Bax)/B-cell lymphoma 2 (Bcl-2) ratio, and poly (ADP-ribose) polymerase 1 (PARP-1) cleavage in HepG2 cells. Furthermore, the results of this study showed that tanshinone IIA significantly decreased HepG2 cell-based tumor growth in nude mice in a dose-dependent manner. On the other hand, the tanshinone IIA-induced apoptotic cell death rate was significantly attenuated by enhanced up-regulation of CYP2J2 expression. Thus, our data strongly suggest that tanshinone IIA exerts its anticancer effect by inhibiting CYP2J2 activity.
Keywords: Cytochrome P450 2J2; Tanshinone IIA; HepG2 cells; Anticancer; Apoptosis;

Effect of silodosin, a selective α1A-adrenoceptor antagonist, on voiding behavior and bladder blood flow in a rat model of bladder outlet obstruction by Yoshiaki Goi; Yoshitaka Tomiyama; Ayaka Yokoyama; Satoshi Tatemichi; Kazuyasu Maruyama; Mamoru Kobayashi; Osamu Yamaguchi (489-496).
This study was performed to investigate the effects of silodosin (selective α1A-adrenoceptor antagonist) on bladder blood flow (BBF) and bladder function in a rat model of bladder outlet obstruction (BOO) and to determine the expression of α1-adrenoceptor subtype mRNA in human and rat bladder microvessels.BOO was produced by partial ligature of the proximal urethra, which was maintained for 2 weeks. The BOO rats received either silodosin at a rate of 0.3 mg/kg/day or vehicle subcutaneously via an osmotic pump for 2 weeks after BOO surgery. A metabolic cage study was performed in conscious animals. BBF was measured using a Laser Speckle Blood Flow Imager. Urinary levels of 8-hydroxy-2′-deoxyguanosine (8-OHdG) and nerve growth factor (NGF) were measured. Immunohistological examinations of nerve distribution and NGF expression in the rat bladder were conducted. The expression of each α1-adrenoceptor subtype mRNA in human and rat bladder microvessels was determined by in situ hybridization. Silodosin ameliorated the increase in voiding frequency and decrease in mean voided volume in BOO rats in the metabolic cage study. Silodosin also abrogated the decrease in BBF in BOO rats. The levels of 8-OHdG and NGF in BOO rats were significantly decreased by administration of silodosin. Silodosin prevented the decrease in nerve distribution and increase in NGF expression. Human and rat bladder microvessels showed expression of all α1-adrenoceptor subtype mRNAs. The results presented here suggest that silodosin improves voiding behavior in rat models with BOO by inducing recovery of BBF.
Keywords: Silodosin; α1A-Adrenoceptor; Bladder blood flow; Bladder outlet obstruction; Ischemia; Nerve growth factor;

A novel GABAA alpha 5 receptor inhibitor with therapeutic potential by István Ling; Balázs Mihalik; Lori-An Etherington; Gábor Kapus; Adrienn Pálvölgyi; Gábor Gigler; Szabolcs Kertész; Attila Gaál; Katalin Pallagi; Péter Kiricsi; Éva Szabó; Gábor Szénási; Lilla Papp; László G. Hársing; György Lévay; Michael Spedding; Jeremy J. Lambert; Delia Belelli; József Barkóczy; Balázs Volk; Gyula Simig; István Gacsályi; Ferenc A. Antoni (497-507).
Novel 2,3-benzodiazepine and related isoquinoline derivatives, substituted at position 1 with a 2-benzothiophenyl moiety, were synthesized to produce compounds that potently inhibited the action of GABA on heterologously expressed GABAA receptors containing the alpha 5 subunit (GABAA α5), with no apparent affinity for the benzodiazepine site. Substitutions of the benzothiophene moiety at position 4 led to compounds with drug-like properties that were putative inhibitors of extra-synaptic GABAA α5 receptors and had substantial blood-brain barrier permeability. Initial characterization in vivo showed that 8-methyl-5-[4-(trifluoromethyl)-1-benzothiophen-2-yl]-1,9-dihydro-2H-[1,3]oxazolo[4,5-h][2,3]benzodiazepin-2-one was devoid of sedative, pro-convulsive or motor side-effects, and enhanced the performance of rats in the object recognition test. In summary, we have discovered a first-in-class GABA-site inhibitor of extra-synaptic GABAA α5 receptors that has promising drug-like properties and warrants further development.Display Omitted
Keywords: GABA; GABAA antagonist; 2,3-Benzodiazepine; Isoquinoline; Benzothiophene; Extrasynaptic receptors; Nootropic agents; Object recognition test;

Phosphodiesterase inhibitor, pentoxifylline enhances anticancer activity of histone deacetylase inhibitor, MS-275 in human breast cancer in vitro and in vivo by Saranya Nidhyanandan; Thippeswamy S. Boreddy; Kothapalli B. Chandrasekhar; Neetinkumar D. Reddy; Nagaraj M. Kulkarni; Shridhar Narayanan (508-519).
MS-275, a histone deacetylase inhibitor (HDACi), is undergoing clinical trials for treatment of various cancers. Pentoxifylline, a nonselective phosphodiesterase (PDE) inhibitor, has been shown to increase the effectiveness of antitumor chemotherapy. In the present study, the potential anti-cancer activity of MS-275 in combination with pentoxifylline in panel of cell lines and human breast cancer xenograft model were examined.A Panel of cancer cell lines were treated with MS-275 and pentoxifylline to determine their impact on cellular proliferation, cell cycle regulation, apoptosis, anti-angiogenesis. The in vivo activities of MS-275 and pentoxifylline were assessed in a Matrigel plug angiogenesis model and human breast cancer (MDA-MB-231) xenograft model.Combination of MS-275 with pentoxifylline showed enhanced anti-proliferative activity in a panel of cancer cell lines (HCT 116, MCF-7, PC3 and MDA-MB-231). Apoptotic studies performed using, Hoechst staining and cell cycle analysis reveal that this combination at the lower concentrations induces apoptosis downstream of the HDAC inhibition and PDE regulation. Further, combination showed enhanced antiangiogenic activity in Matrigel tube formation assay using HUVECs and in Matrigel plug assay in vivo. A significant inhibition (P<0.001) of tumor growth was observed in mice bearing MDA-MB-231 breast cancer xenograft treated with the combination of MS-275 (5 mg/kg p.o.) and pentoxifylline (60 mg/kg i.p.) than treatments alone, without much signs of toxicity.Taken together, our study demonstrated enhanced anticancer activity of MS-275 and pentoxifylline combination both in vitro and in vivo with reduced toxicity. However, further studies are required to understand the mechanism for this combination effect.
Keywords: HDAC; MS-275; PDE; Pentoxifylline; Apoptosis; Xenograft;

A natural xanthone increases catalase activity but decreases NF-kappa B and lipid peroxidation in U-937 and HepG2 cell lines by Binay K. Sahoo; Adeel H. Zaidi; Pankaj Gupta; Raveendra B. Mokhamatam; Nune Raviprakash; Sidhartha K. Mahali; Sunil K. Manna (520-528).
Mangiferin, a C-glycosyl xanthone, has shown anti-inflammatory, antioxidant, and anti-tumorigenic activities. In the present study, we investigated the molecular mechanism for the antioxidant property of mangiferin. Considering the role of nuclear transcription factor kappa B (NF-κB) in inflammation and tumorigenesis, we hypothesized that modulating its activity will be a viable therapeutic target in regulating the redox-sensitive ailments. Our results show that mangiferin blocks several inducers, such as tumor necrosis factor (TNF), lypopolysaccharide (LPS), phorbol-12-myristate-13-acetate (PMA) or hydrogen peroxide (H2O2) mediated NF-κB activation via inhibition of reactive oxygen species generation. In silico docking studies predicted strong binding energy of mangiferin to the active site of catalase (−9.13 kcal/mol), but not with other oxidases such as myeloperoxidase, glutathione peroxidase, or inducible nitric oxide synthase. Mangiferin increased activity of catalase by 44%, but had no effect on myeloperoxidase activity in vitro. Fluorescence spectroscopy further revealed the binding of mangiferin to catalase at the single site with binding constant and binding affinity of 3.1×10−7  M−1 and 1.046 respectively. Mangiferin also inhibits TNF-induced lipid peroxidation and thereby protects apoptosis. Hence, mangiferin with its ability to inhibit NF-κB and increase the catalase activity may prove to be a potent therapeutic.
Keywords: Catalase; NF-κB; Mangiferin; Oxidative stress; Antioxidant; TNF;

Drinking sucrose or saccharin enhances sensitivity of rats to quinpirole-induced yawning by Katherine M. Serafine; Todd A. Bentley; Dylan J. Kilborn; Wouter Koek; Charles P. France (529-536).
Diet can impact sensitivity of rats to some of the behavioral effects of drugs acting on dopamine systems. The current study tested whether continuous access to sucrose is necessary to increase yawning induced by the dopamine receptor agonist quinpirole, or if intermittent access is sufficient. These studies also tested whether sensitivity to quinpirole-induced yawning increases in rats drinking the non-caloric sweetener saccharin. Dose–response curves (0.0032–0.32 mg/kg) for quinpirole-induced yawning were determined once weekly in rats with free access to standard chow and either continuous access to water, 10% sucrose solution, or 0.1% saccharin solution, or intermittent access to sucrose or saccharin (i.e., 2 days per week with access to water on other days). Cumulative doses of quinpirole increased then decreased yawning, resulting in an inverted U-shaped dose–response curve. Continuous or intermittent access to sucrose enhanced sensitivity to quinpirole-induced yawning. Continuous, but not intermittent, access to saccharin also enhanced sensitivity to quinpirole-induced yawning. In all groups, pretreatment with the selective D3 receptor antagonist PG01037 shifted the ascending limb of the quinpirole dose–response curve to the right, while pretreatment with the selective D2 receptor antagonist L-741,626 shifted the descending limb to the right. These results suggest that even intermittent consumption of diets containing highly palatable substances (e.g. sucrose) alters sensitivity to drugs acting on dopamine systems in a manner that could be important in vulnerability to abuse drugs.
Keywords: Rat; Yawning; Dopamine receptor; Fat; Sucrose; Saccharin; Intermittent access; Quinpirole;

The antidepressant-like activity of 6-methoxy-2-[4-(2-methoxyphenyl)piperazin-1-yl]-9H-xanthen-9-one involves serotonergic 5-HT1A and 5-HT2A/C receptors activation by Karolina Pytka; Maria Walczak; Agnieszka Kij; Anna Rapacz; Agata Siwek; Grzegorz Kazek; Adrian Olczyk; Adam Gałuszka; Anna Waszkielewicz; Henryk Marona; Jacek Sapa; Barbara Filipek (537-546).
Xanthone derivatives have been shown to posses many biological properties. Some of them act within the central nervous system and show neuroprotective or antidepressant-like properties. Taking this into account we investigated antidepressant-like activity in mice and the possible mechanism of action of 6-methoxy-2-[4-(2-methoxyphenyl)piperazin-1-yl]-9H-xanthen-9-one (HBK-11) – a new xanthone derivative. We demonstrated that HBK-11 produced antidepressant-like effects in the forced swim test and tail suspension test, comparable to that of venlafaxine. The combined treatment with sub-effective doses of HBK-11 and fluoxetine (but not reboxetine or bupropion) significantly reduced the immobility in the forced swim test. Moreover, the antidepressant-like activity of HBK-11 in the aforementioned test was blocked by p-chlorophenylalanine, and significantly reduced by serotonergic 5HT1A receptor antagonist – WAY-1006335 and 5HT2A/C receptor antagonist – ritanserin. As none of the above treatments influenced the spontaneous locomotor activity, it can be concluded that HBK-11 mediates its activity through a serotonergic system, and its antidepressant-like effect involves 5HT1A and 5HT2A/C receptor activation. Furthermore, at antidepressant-like doses HBK-11 did not cause the mice to display locomotor deficits in rotarod or chimney tests. Considering the pharmacokinetic profile, HBK-11 demonstrated rapid absorption after i.p. administration, high clearance value, short terminal half-life, very high volume of distribution and incomplete bioavailability. The compound studied had good penetration into the brain tissue of mice. Since studied xanthone derivative seems to present interesting, untypical mechanism of antidepressant-like action i.e. 5HT2A/C receptor activation, it may have a potential in the treatment of depressive disorders, and surely requires further studies.
Keywords: Antidepressant-like activity; 5-HT1A receptor; 5-HT2 receptor; Bioavailability; Distribution in brain; Mass spectrometry;

Effect of galantamine on adjuvant-induced arthritis in rats by Mennatallah A. Gowayed; Rowaida Refaat; Walid M. Ahmed; Hanan S. El-Abhar (547-553).
Stimulation of the vagus nerve suppresses cytokine production and macrophage activation, via the interaction of its neurotransmitter acetylcholine (ACh) with the α7 subunit of the nicotinic acetylcholine receptor (α7nAChR), present on neurons and inflammatory cells. The present study aimed to verify the potential anti-inflammatory effect of galantamine against experimental arthritis induced in rats. Fourteen days post adjuvant injection, Sprague-Dawley rats were treated orally with three doses of galantamine (1.25, 2.5 and 5 mg/kg) or leflunomide (10 mg/kg) for 2 weeks and arthritis progression was assessed by hind paw swelling. Additionally, serum biomarkers, viz., anti-cyclic citrullinated peptide antibodies (Anti-CCP), tumor necrosis factor-α (TNF-α), interleukin-10 (IL-10) and monocyte chemoattractant protein-1 (MCP-1) were measured. Radiological examination of the hind paws was also carried out to evaluate the degree of joint damage.Adjuvant arthritis led to a significant weight loss, marked swelling of the hind paw and alteration in the serum levels of anti-CCP, TNF-α, IL-10 and MCP-1. These alterations were associated with significant radiological changes of the joints. Galantamine, in a dose-dependent manner, reduced significantly all biomarkers of inflammation, with the highest dose showing the best beneficial anti-inflammatory effect that was superior in magnitude to the reference drug leflunomide in most of the studied parameters. In conclusion, these results suggest that galantamine may represent a novel, inexpensive and effective therapeutic strategy in the treatment of rheumatoid arthritis.
Keywords: Adjuvant-induced arthritis; Galantamine; Anti-CCP; TNF-α; IL-10; MCP-1;

SIRT2 regulates microtubule stabilization in diabetic cardiomyopathy by Qiong Yuan; Lin Zhan; Qian-Yi Zhou; Li-Li Zhang; Xu-Meng Chen; Xia-Min Hu; Xin-Chu Yuan (554-561).
Stable microtubules (MTs) is involved the mechanism of diabetic cardiomyopathy (DCM), which is induced by acetylation of α-tubulin. The present study investigated whether SIRT2, a deacetylase, regulates MT stability through α-tubulin deacetylation in DCM and whether the receptor of advanced glycation end products (AGEs) signaling pathway is involved in this effect. Type 1 diabetic mellitus (T1DM) rats model was established by a single intraperitoneal injection of streptozotocin (STZ, 65 mg/kg), and neonatal rat cardiomyocytes were also cultured. Heart function was detected by Doppler. MT stability was elevated by β-tubulin expression density. The protein expression of SIRT2, acetylated α-tubulin and AGEs receptor were detected by immunohistochemistry or Western blots. The interaction of SIRT2 and acetylated α-tubulin was detected by Co-immunoprecipitation. In an animal model of T1DM, Western blots and immunohistochemistry revealed downregulation of SIRT2 but upregulation of the acetylated α-tubulin protein. These effects were reduced by treatment of aminoguanidine, an inhibitor of AGEs production. HDAC6 expression did not regulated in heart. In primary cultures of neonatal rat cardiomyocytes, the AGEs treatment impaired the SIRT2/acetylated α-tubulin signaling pathway, and SIRT2-overexpression reversed the function of AGEs on cardiomyocytes. In addition, gene silencing of AGEs receptor alleviated the impairment effect of AGEs on cardiomyocytes. In conclusion, these data demonstrate that AGEs/AGEs receptor promote MT stabilization via the suppression of the SIRT2/acetylated α-tubulin signaling pathway in DCM development.
Keywords: SIRT2; Acetylated α-tubulin; Diabetic cardiomyopathy; Advanced glycation end products; Receptor for advanced glycation end products; Aminoguanidine;

The precise mechanisms by which cocaine and amphetamine-like psychostimulants exert their reinforcing effects are not yet fully defined. It is widely believed, however, that these drugs produce their effects by enhancing dopamine neurotransmission in the brain, especially in limbic areas such as the nucleus accumbens, by inducing dopamine transporter-mediated reverse transport and/or blocking dopamine reuptake though the dopamine transporter. Here, we present the evidence that aside from dopamine transporter, non-dopamine transporter-mediated mechanisms also participate in psychostimulant-induced dopamine release and contribute to the behavioral effects of these drugs, such as locomotor activation and reward. Accordingly, psychostimulants could increase norepinephrine release in the prefrontal cortex, the latter then alters the firing pattern of dopamine neurons resulting in changes in action potential-dependent dopamine release. These alterations would further affect the temporal pattern of dopamine release in the nucleus accumbens, thereby modifying information processing in that area. Hence, a synaptic input to a nucleus accumbens neuron may be enhanced or inhibited by dopamine depending on its temporal relationship to dopamine release. Specific temporal patterns of dopamine release may also be required for certain forms of synaptic plasticity in the nucleus accumbens. Together, these effects induced by psychostimulants, mediated through a non-dopamine transporter-mediated mechanism involving norepinephrine and the prefrontal cortex, may also contribute importantly to the reinforcing properties of these drugs.
Keywords: Psychostimulants; Dopamine transporter; Prefrontal cortex; Dopamine neuron; Firing pattern; Oscillations;

Alzheimer’s disease (AD) is a complex, progressive neurological disorder affecting elderly population of above 65 years of age, characterized by failure of memory, loss of acquired skills leading to apraxia, agnosia, aphasia and frequent disturbances in emotion with interpersonal and social deterioration. The extracellular senile plaques and intracellular neurofibrillary tangles composed of amyloid beta protein and highly phosphorylated tau protein, the key components involved in pathogenesis of AD are considered as the pathological hallmark of this disease. This has led to immense development in the field of treatment for AD. Recent evidences suggest that removal of protein deposits from AD brains are the newer attempts for treating AD. The major developments in this direction are the amyloid and tau based therapeutics, which could hold the key to treatment of AD in the near future. Several putative drugs have been thoroughly investigated in preclinical studies, but many of them have failed to produce results in the clinical scenario. Therefore, failures from the past can be treated as lessons for the development of efficacious drugs. In addition to this, various non- pharmacological interventions and miscellaneous drugs are also being used now for combating the AD like disease progression. Thus, present review discusses about the disease modifying therapies together with the various non-pharmacological interventions and miscellaneous drugs for treating AD.
Keywords: Alzheimer’s disease; Amyloid beta; Tau phosphorylation; Herbal supplements; Miscellaneous therapies; Physical work and exercise;

KATP channel block prevents proteasome inhibitor-induced apoptosis in differentiated PC12 cells by Yoon Jeong Nam; Da Hee Lee; Min Sung Lee; Chung Soo Lee (582-591).
Dysfunction of the proteasome system has been suggested to be implicated in neuronal degeneration. Modulation of KATP channels appears to affect the viability of neuronal cells exposed to toxic insults. However, the effect of KATP channel blockers on the neuronal cell death mediated by proteasome inhibition has not been studied. The present study investigated the effect of KATP channel blockers on proteasome inhibitor-induced apoptosis in differentiated PC12 cells and SH-SY5Y cells. 5-Hydroxydecanoate (a selective KATP channel blocker) and glibenclamide (a cell surface and mitochondrial KATP channel inhibitor) reduced the proteasome inhibitor-induced apoptosis. Addition of the KATP channel blockers attenuated the proteasome inhibitor-induced changes in the levels of apoptosis-related proteins, the loss of the mitochondrial transmembrane potential, the increase in the formation of reactive oxygen species and the depletion of glutathione in both cell lines. The results show that KATP channel blockers may attenuate proteasome inhibitor-induced apoptosis in PC12 cells by suppressing activation of the mitochondrial pathway and of the caspase-8- and Bid-dependent pathways. The preventive effect appears to be associated with the inhibition of the formation of reactive oxygen species and the depletion of glutathione. KATP channel blockade appears to prevent proteasome inhibition-induced neuronal cell death.
Keywords: Proteasome inhibitors; KATP channel blockers; PC12 cells; Apoptosis-related proteins; Protection;

Adenosine A1 receptors are selectively coupled to Gαi-3 in postmortem human brain cortex: Guanosine-5′-O-(3-[35S]thio)triphosphate ([35S]GTPγS) binding/immunoprecipitation study by Yuji Odagaki; Masakazu Kinoshita; Toshio Ota; J. Javier Meana; Luis F. Callado; Jesús A. García-Sevilla (592-598).
By means of guanosine-5′-O-(3-[35S]thio)triphosphate ([35S]GTPγS) binding assay combined with immunoprecipitation using anti-Gα subunit antibody, we recently reported 5-HT2A receptor- and M1 muscarinic acetylcholine receptor-mediated Gαq activation in rat cerebral cortical membranes (Odagaki et al., 2014). In the present study, this method has been applied to postmortem human brains, with focusing on adenosine receptor-mediated G-protein activation. In the exploratory experiments using a series of agonists and the antibodies specific to each Gα subtypes in the presence of low (10 nM) or high (50 μM) concentration of GDP, the most prominent increases in specific [35S]GTPγS binding in the membranes prepared from human prefrontal cortex were obtained for the combinations of adenosine (1 mM)/anti-Gαi-3 in the presence of 50 μM GDP as well as 5-HT (100 μM)/anti-Gαq and carbachol (1 mM)/anti-Gαq in the presence of 10 nM GDP. Adenosine-induced activation of Gαi-3 emerged only when GDP concentrations were increased higher than 10 μM, and the following experiments were performed in the presence of 300 μM GDP. Adenosine increased specific [35S]GTPγS binding to Gαi-3 in a concentration-dependent manner to 251.4% of the basal unstimulated binding, with an EC50 of 1.77 μM. The involvement of adenosine A1 receptor was verified by the experiments using selective agonists and antagonists at adenosine A1 or A3 receptor. Among the α subunits of Gi/o class (Gαi-1, Gαi-2,i-3, and Gαo.), only Gαi-3 was activated by 1 mM adenosine, indicating that human brain adenosine A1 receptor is coupled preferentially, if not exclusively, to Gαi-3.
Keywords: Adenosine A1 receptor; G-protein; [35S]GTPγS binding; Immunoprecipitation; Postmortem human brain;

Metformin attenuates hyperalgesia and allodynia in rats with painful diabetic neuropathy induced by streptozotocin by Junxiong Ma; Hailong Yu; Jun Liu; Yu Chen; Qi Wang; Liangbi Xiang (599-606).
Painful diabetic neuropathy is a common complication of diabetes mellitus, which often makes the patients suffer from severe hyperalgesia and allodynia. Thus far, the treatment of painful diabetic neuropathy remains unsatisfactory. Metformin, which is the first-line drug for type-2 diabetes, has been proved to attenuate hyperexcitability in sensory neurons linked to chemotherapy-induced neuropathic pain, highlighting its potential in alleviating pain related with painful diabetic neuropathy. The present study was designed to investigate the potential beneficial effect of metformin on hyperalgesia and allodynia in diabetic rats. The mechanical sensitivity, heat nociception, and cold allodynia were examined. The levels of malondialdehyde, superoxide dismutase, and advanced glycation end-products in the blood were measured. The expression of adenosine monophosphate-activated protein kinase (AMPK) phosphorylation and AMPK target genes were examined in the sciatic nerves of the animals. It was found that metformin was capable of attenuating diabetes-induced mechanical hyperalgesia, heat hyperalgesia and cold allodynia. In addition, metformin was capable of decreasing malondialdehyde and glycation end-products levels in blood, as well as increasing superoxide dismutas activity, indicating the inhibitory effect of metformin against diabetes-induced oxidative stress. Further studies showed that metformin could activate AMPK and increase the AMPK target genes in sciatic nerves in diabetic rats. In conclusion, metformin is able to attenuate diabetes-induced hyperalgesia and allodynia, which might be associated its anti-oxidative effect through AMPK pathway. Metformin might be used as an effective drug, especially with fewer side effects, for abnormal sensation in painful diabetic neuropathy.
Keywords: Metformin; Hyperalgesia; Allodynia; Painful diabetic neuropathy; AMPK;

TRAM-Derived Decoy Peptides inhibits the inflammatory response in mouse mammary epithelial cells and a mastitis model in mice by Xiaoyu Hu; Yuan Tian; Tiancheng Wang; Wenlong Zhang; Wei Wang; Xuejiao Gao; Shihui Qu; Yongguo Cao; Naisheng Zhang (607-612).
It has been proved that TRAM-Derived Decoy peptides have anti-inflammatory properties. In this study, we synthesized a TRAM-Derived decoy peptide (TM6), belongs to TRAM TIR domain, of which sequence is “N”-RQIKIWFQNRRMKWK, KENFLRDTWCNFQFY-“C” and evaluated the effects of TM6 on lipopolysaccharide-induced mastitis in mice. In vivo, LPS-induced mice mastitis model was established by injection of LPS through the duct of mammary gland. TM6 was injected 1 h before or after LPS treatment. In vitro, primary mouse mammary epithelial cells were used to investigate the effects of TM6 on LPS-induced inflammatory responses. The results showed that TM6 inhibited LPS-induced mammary gland histopathologic changes, MPO activity, and TNF-α, IL-1β and IL-6 production in mice. In vitro, TM6 significantly inhibited LPS-induced TNF-α and IL-6 production, as well as NF-κB and MAPKs activation. In conclusion, this study demonstrated that TM6 had protective effects on LPS-mastitis and may be a promising therapeutic reagent for mastitis treatment.
Keywords: TRAM-Derived Decoy Peptide; LPS; Cytokines; TLR4; Mastitis;

β-Caryophyllene alleviates d-galactosamine and lipopolysaccharide-induced hepatic injury through suppression of the TLR4 and RAGE signaling pathways by Hong-Ik Cho; Jeong-Min Hong; Joo-Wan Choi; Hyo-Sun Choi; Jong Hwan Kwak; Dong-Ung Lee; Sang Kook Lee; Sun-Mee Lee (613-621).
Agastache rugosa (A. rugosa, Labiatae), a perennial herb spread throughout Korean fields, is widely consumed as a wild edible vegetable and is used in folk medicine. This study examined the hepatoprotective mechanisms of β-caryophyllene (BCP), a major bicyclic sesquiterpene of A. rugosa, against d-galactosamine (GalN) and lipopolysaccharide (LPS)-induced hepatic failure. Mice were given an intraperitoneal injection of BCP (50, 100 and 200 mg/kg) 1 h before GalN (800 mg/kg)/LPS (40 μg/kg) injection and were killed 1 h or 6 h after GalN/LPS injection. GalN/LPS markedly increased mortality and serum aminotransferase activity, both of which were attenuated by BCP. BCP also attenuated increases in serum tumor necrosis factor-α, interleukin 6, and high-mobility group protein B1 levels by GalN/LPS. GalN/LPS significantly increased toll-like receptor (TLR) 4 and receptor for advanced glycation end products (RAGE) protein expression, extracellular signal-related kinase, p38 and c-Jun N-terminal kinase phosphorylation, nuclear factor κB (NF-κB), early growth response protein-1, and macrophage inflammatory protein-2 protein expression. These increases were attenuated by BCP. Furthermore, BCP suppressed increased TLR4 and RAGE protein expression and proinflammatory cytokines production in LPS-treated isolated Kupffer cells. Our findings suggest that BCP protects against GalN/LPS-induced liver injury through down-regulation of the TLR4 and RAGE signaling.Display Omitted
Keywords: β-Caryophyllene; Fulminant hepatic failure; High-mobility group box 1; Receptor for advanced glycation end products; Toll-like receptor 4;

Interaction of propofol with voltage-gated human Kv1.5 channel through specific amino acids within the pore region by Akiko Kojima; Yuki Ito; Wei-Guang Ding; Hirotoshi Kitagawa; Hiroshi Matsuura (622-632).
The intravenous anesthetic propofol affects the function of a diversity of ligand-gated and voltage-gated ion channels. However, there is little information as to whether propofol directly interacts with voltage-gated ion channel proteins to modulate their functions. The Kv1.5 channel is activated by membrane depolarization during action potentials and contributes to atrial repolarization in the human heart. This study was undertaken to examine the effect of propofol on voltage-gated human Kv1.5 (hKv1.5) channel and to elucidate the underlying molecular determinants. Site-directed mutagenesis was carried out through six amino acids that reside within the pore domain of hKv1.5 channel. Whole-cell patch-clamp technique was used to record membrane currents through the wild type and mutant hKv1.5 channels heterologously expressed in Chinese hamster ovary cells. Propofol (≥5 μM) reversibly and concentration-dependently (IC50 of 49.3±9.4 μM; n=6) blocked hKv1.5 current. Propofol-induced block of hKv1.5 current gradually progressed during depolarizing voltage-clamp steps and was enhanced by higher frequency of activation, consistent with a preferential block of the channels in their open state. The degree of current block by propofol was significantly attenuated in T480A, I502A, I508A and V516A, but not in H463C and L510A mutants of hKv1.5 channel. Thus, several amino acids near the selectivity filter (Thr480) or within S6 (Ile502, Ile508 and Val516) are found to be critically involved in the blocking action of propofol. This study provides the first evidence suggesting that direct interaction with specific amino acids underlies the blocking action of propofol on voltage-gated hKv1.5 channel.
Keywords: Propofol; Kv1.5; Mutagenesis; Pore region; Amino acid; Open channel block;

Tannic acid modulates excitability of sensory neurons and nociceptive behavior and the Ionic mechanism by Xuan Zhang; Huiran Zhang; Najing Zhou; Jiaxi Xu; Man Si; Zhanfeng Jia; Xiaona Du; Hailin Zhang (633-642).
M/Kv7 K+ channels, Ca2+-activated Cl channels (CaCCs) and voltage gated Na+ channels expressed in dorsal root ganglia (DRG) play an important role in nociception. Tannic acid has been proposed to be involved in multiple beneficial health effects; tannic acid has also been described to be analgesic. However the underlying mechanism is unknown. In this study, we investigated the effects of tannic acid on M/Kv7 K+, Na+ currents and CaCCs, and the effects on bradykinin-induced nociceptive behavior. A perforated patch technique was used. The bradykinin-induced rat pain model was used to assess the analgesic effect of tannic acid. We demonstrated that tannic acid enhanced M/Kv7 K+ currents but inhibited bradykinin-induced activation of CaCC/TMEM16A currents in rat small DRG neurons. Tannic acid potentiated Kv7.2/7.3 and Kv7.2 currents expressed in HEK293B cells, with an EC50 of 7.38 and 5.40 µM, respectively. Tannic acid inhibited TTX-sensitive and TTX-insensitive currents of small DRG neurons with IC50 of 5.25 and 8.43 µM, respectively. Tannic acid also potently suppressed the excitability of small DRG neurons. Furthermore, tannic acid greatly reduced bradykinin-induced pain behavior of rats. This study thus demonstrates that tannic acid is an activator of M/Kv7 K+ and an inhibitor of voltage-gated Na+ channels and CaCC/TMEM16A, which may underlie its inhibitory effects on excitability of DRG neurons and its analgesic effect. Tannic acid could be a useful agent in treatment of inflammatory pain conditions such as osteoarthritis, rheumatic arthritis and burn pain.
Keywords: Tannic acid; M/Kv7 K+ currents; CaCCs; Voltage-gated Na+ currents; Bradykinin; Pain;