Biochemistry (Moscow), Supplement Series B: Biomedical Chemistry (v.5, #4)

Mitochondrial dysfunction in Parkinson’s disease by O. A. Buneeva; A. E. Medvedev (313-336).
The review highlights mitochondrial structural and functional abnormalities in Parkinson’s disease and experimental animal models of this pathology. Special attention is paid to the inactivation of mitochondrial enzymes, mutations in mitochondrial and nuclear DNA, and genomic and proteomic studies of mitochondrial proteins in Parkinson’s disease and experimental parkinsonism in animals.
Keywords: Parkinson’s disease; mitochondria; mitochondrial enzymes; genomics; proteomics

L-Amino acid oxidases: Properties and molecular mechanisms of action by E. V. Lukasheva; A. A. Efremova; E. M. Treshalina; A. Yu. Arinbasarova; A. G. Medentzev; T. T. Berezov (337-345).
During the last 10–15 years L-amino acid oxidases (LAAO) are intensively studied due to their diverse effects on various biological objects. The review summarized information about sources, structure, physicochemical, and catalytic properties of LAAO as well as data on their antibacterial, antifungal, antiprotozoal, antiviral, antiproliferative, and antitumor effects, and on ambiguous effects on platelet aggregation. Special attention is paid to analysis of literature data on elucidation of molecular mechanisms of the LAAO action. It is proposed that the unique properties of LAAO are associated the decrease of L-amino acid levels, including the essential amino acids and formation of hydrogen peroxide, which indirectly (via reactive oxygen species, ROS) acts on cells and triggers biological mechanisms of apoptosis and necroses. The presence of carbohydrate components in LAAO molecules promotes enzyme attachment to the cell surface and creation of high local concentrations of hydrogen peroxide. The wide range of biological effects of LAAO in vivo is usually associated with their functional importance. For example, in the mouse brain the LAAO-catalyzed reaction is the only reaction for L-lysine degradation, while in the mouse milk LAAO acts as a bactericide agent. Leukocyte LAAO is involved in realization of the systemic anti-infective effect. The protective action is also attributed to the oxidases from the other numerous sources including microscopic fungi, snake venoms and sea inhabitants.
Keywords: L-amino acid oxidase (LAAO); L-lysine α-oxidase; cytotoxicity; anticancer properties; antiviral properties; apoptosis

Calculations of acute intravenous toxicity in mice based on local regression models in superoverlapping clusters (LRMSC) by O. A. Raevsky; V. Yu. Grigoriev; E. A. Liplavskaya; A. P. Worth (346-356).
Modeling of quantitative structure — activity relationships (QSAR) between physicochemical descriptors of organic chemicals and their acute intravenous toxicity in mice have been presented. This approach includes three steps: structure-similarity chemicals selection for every compound-of-interest (clusterization); construction of quantitative structure — toxicity models for every cluster (without including of compounds-of-interest); application of the obtained QSAR equations for chemical-of-interest toxicity estimation. This approach has been applied for calculations of acute intravenous toxicity for 10241 organic chemicals. For 7759 compounds possessing structural neighbors with the Tanimoto index (Tc) of 0.30 and above the standard deviation of the calculated vs. experimental log(1/LD50) values was 0.51 at the estimation of the experimental determination error of ±0.50 (log(1/LD50) value). Calculations performed for remaining compounds (∼24%) were not as good as those made for the former group, possibly due to lack of reasonable number of structurally related analogues. It’s suggested that this QSAR approach can be useful for prediction of biological activity and toxicity of large sets of chemical compounds.
Keywords: QSAR; toxicity; structural similarity; HYBOT; DRAGON; clusterization; regression models

A correlation between changes in activities of myocardial glutathione peroxidase (GPx), glutathione reductase (GR) and the intensity of free radical processes estimated by biochemiluminescence parameters and the content of lipoperoxidation products has been demonstrated in rats during development of adrenaline myocarditis. The maximal increase of GPx and GR activities (1.8- and 1.4-fold, respectively) was observed 24 h after the development of the pathological process; this coincided with the maximal intensity of free radical oxidation. Using combination of reverse transcriptions with real-time polymerase chain reaction the cardiac mRNA levels of genes encoding GPx and GR were determined 24 h after the development of adrenaline myocarditis in rats. Analysis of expression of GPx and GR genes revealed a 2.8- and 7.3-fold increase of their transcripts in rats with adrenaline myocarditis, respectively. Obviously, overexpression of these enzymes can increase cardiomyocite resistance to oxidative stress.
Keywords: overexpression; oxidative stress; myocarditis; glutathione peroxidase; glutathione reductase

Reactions of peroxidase oxidation of triftazine and thioproperazine have been investigated in the presence of horseradish peroxidase using steady state kinetic methods. It has been shown that phenothiazines are slowly oxidizable substrates for horseradish peroxidase. k cat and K m values have been determined in the range of pH from 4.5 to 7.5. The study of co-oxidation of phenothiazines and o-dianisidine (ODN) revealed that in the presence of aminazine and ODN in the reaction medium both substances follow sequential oxidation. ODN oxidation was not observed until full conversion of aminazine. At pH 4.5–5.5 thioproperazine bound to the enzyme-substrate complex and caused anticompetitive inhibition of peroxidase. At pH > 5.5 sequential substrate oxidation with preferential thioproperazine conversion occurred. In the range of pH from 4.5 to 7.5 triftazine did not influence ODN oxidation.
Keywords: horseradish peroxidase; triftazine; thioproperazine; aminazine; o-dianisidine; phenothiazines

Using Guerin’s carcinoma as a model the interrelationship between the tumor growth process and supplementation of the body with vitamin A has been studied. The replenishment of vitamin A resources of vitamin-deficient tumor bearing animals modulated the Guerin’s carcinoma growth rate in a dose dependent manner (r = 0.83). The morphological parameters of tumor growth under conditions of supplementation with vitamin A (0–3000 IU) positively correlated with hydroxylase (r = 0.81) and demethylase (r = 0.49) activities of the Guerin’s carcinoma cytochrome P450 system. The increase in the tumor growth rate together with the induction of hydroxylase and demethylase activities of cytochrome P450 in the Guerin’s carcinoma microsomal fraction, observed either under conditions of retinyl acetate overdose supplementation, or selective liposomal form of all-trans-retinoic acid, suggests the stimulatory effect of retinoids on tumor growth.
Keywords: retinoids; cytochrome P450; Guerin’s carcinoma

A functional state of the sphingomyelin cycle and activity of free radical oxidation of rat liver lipids at different phases of starvation by D. I. Kuzmenko; P. G. Burov; V. Yu. Serebrov; E. A. Fait; T. V. Perevozchikova (376-380).
A functional state of the sphingomyeline cycle and its links with processes of free radical lipid oxidation have been investigated in rat liver during starvation of animals without any restriction of access to drinking water at day 1, 2, 3 (phase I) and day 6 (phase II of starvation). The maximal values of the ceramide/sphingomyelin ratio and activities of neutral sphingomyelinase and executive caspase-3 were found in rat livers at day 3 of starvation. Since day 3 of starvation an increase of tumour necrosis factor-α, one of neutral sphingomyelinase activators, was detected in serum. During the major part of phase I of starvation the intensity of liver free radical lipid peroxidation was comparable to that of control due to competent functioning of the antioxidant defense system. Transition of phase I to phase II of starvation (day 6 of the experiment) was accompanied by the development of oxidative stress associated with depletion of the antioxidant defense system. The results obtained in this study suggest that phase I of starvation favors realization of the ceramide-mediated proapoptotic signaling in the liver. In our viewpoint, ceramide-mediated apoptosis is one of mechanisms used optimization of liver cellular population within the frame of metabolic adaptation. In rat liver phase I of starvation was characterized by prevailing of the ceramide-mediated proapoptotic signaling, while in phase II oxidative stress dominated.
Keywords: starvation; sphingomyelin cycle; free radical lipid oxidation

The absorption features of glycyrrhizic acid in the drug formulation Phosphogliv by A. A. Voskresenskaya; N. V. Medvedeva; V. N. Prozorovskii; N. E. Moskaleva; O. M. Ipatova (381-386).
Glycyrrhizic acid (GL), one of the active components of the Russian drug formulation Phosphogliv, is characterized by extremely low bioavailability. Absorption characteristics of GL after peroral administration of “Phosphogliv“ and GL sodium salt have been investigated using a sensitive method developed for GL determination in blood by means of high performance liquid chromatography coupled with mass-spectrometry (LC-MS). Separation of blood components was achieved on the analytical reverse-phase column C18 “EcoNova” ProntoSIL, using a gradient mode. Detection of GL and an internal standard (IS) (glycyrrhetic acid) was performed using electrospray ionization with the selected ion monitoring in negative mode (SIM) using the target ions of m/z 821.3 and 469.3 for GL and IS, respectively. The calibration curve was linear over the range of concentrations 50–5000 ng/ml (the correlation coefficient was 0.995). The detection limit for GL in blood was 25 ng/ml and the lower limit of quantification was 50 ng/ml. The developed method has been applied to compare absorption efficiency of GL as the component of the Phosphogliv drug formulation and solution of GL sodium salt during the first two hours after their single peroral administration to rats at the dose of 8.5 mg/kg. It was shown that GL absorption occurred within several minutes after peroral administration. Moreover, GL bioavailability after Phosphogliv administration was higher than after administration of GL sodium salt. This difference may be attributed to GL incorporation of the phospholipid nanoparticles structure.
Keywords: drug bioavailability; Phosphogliv; monitoring; glycyrrhizic acid; glycyrrhetic acid; LC-MS

Activity of the first line antioxidant defense enzymes in the liver of pubertal rats during stress by Yu. V. Volkova; L. L. Sukhova; V. V. Davydov; A. V. Goloborod’ko (387-389).
Activities of catalase, glutathione peroxidase (GPx) and superoxide dismutase (SOD) have been investigated in the liver postmitochondrial fraction of pubertal rats exposed to stress. Short-term immobilization of pubertal rats caused a decrease of catalase and GPx activities. Long-term immobilization was accompanied by activation of GPx and SOD in the liver postmitochondrial fraction of late pubertal and adult animals, but not early pubertal rats.
Keywords: puberty; stress; superoxide dismutase; glutathione peroxidase; catalase; liver

The effect of oxidized and unoxidized fibrinogen on apoptosis of endothelial cells by A. V. Aseychev; O. A. Azizova; O. N. Scheglovitova; N. N. Sklyankina; G. G. Borisenko (390-396).
Oxidative stress plays an important role in cardiovascular diseases and atherosclerosis. Fibrinogen (FB), a central protein of the plasma coagulation cascade, is an independent risk factor of atherosclerosis. Importantly, it can be readily oxidized during oxidative stress and in various pathological conditions. Since endothelial dysfunction plays a key role in atherosclerosis it is interesting to investigate the effect of oxidized fibrinogen (ox-FB) on human umbilical vein endothelial cells (HEC). Here, we have investigated the effect of ox-FB on the development of programmed death of HEC incubated in vitro for 24 h under two different conditions: (1) at low serum level (0.1%) and in the absence of growth factors (“starvation”); (2) in full medium (5% human fetal serum) with growth factor supplement. Apoptosis was evaluated using analysis of nuclear morphology, phosphatidylserine externalization on the HEC surface and caspase-3 activation. Under starvation conditions characterized by significant cell death and activation of apoptosis addition of unoxidized FB significantly improved cell survival and prevented caspase-3/7 activation. In the presence of ox-FB caspase activity was 1.5 times higher than in the presence of FB, nevertheless, ox-FB demonstrated significant protection of HEC. Under optimal cultivation conditions FB caused a 3-fold decrease in the rate of apoptosis, while ox-FB improved cell survival but it was less active than FB. Thus, FB promoted HEC survival under stress conditions (in starvation), however, oxidative modification of this protein decreased its antiapoptotic activity.
Keywords: apoptosis; atherosclerosis; endothelial cells; oxidative stress; oxidized fibrinogen

Catecholamine metabolism in children with Asperger’s and Kanner’s syndromes by A. S. Gorina; L. S. Kolesnichenko; V. I. Mikhnovich (397-401).
In a stable state children with Asperger’s and Kanner’s syndromes demonstrate a similar decrease in plasma norepinephrine. In the aggravated state, these changes become more expressed and are characterized by a decrease in plasma tyrosine, norepinephrine, normetanephrine, and by an increase in dopamine and homovanillic acid and a decrease in excretion of norepinephrine and an increase in excretion of homovanillic acid, epinephrine and 3-methoxy-4-hydroxyphenylglycol (MHPG). In the aggravated state children with Kanner’s syndrome were characterized by increased plasma MHPG, decreased excretion of tyrosine and increased expression of normetanephrine. The observed imbalance in dopamine and epinephrine/norepinephrine systems suggests importance of combined analysis of changes in catecholamines and their metabolites as the most informative approach in the study of the effect of autistic disorders.
Keywords: Asperger’s syndrome; Kanner’s syndrome; catecholamines; dopamine; norepinephrine; tyrosine