Anti-Inflammatory & Anti-Allergy Agents in Medicinal Chemistry (v.15, #3)

Meet Our Editorial Board Member by Rosa Tundis (153-153).

Background: Ketoprofen, a potent anti-inflammatory, analgesic and anti-pyretic drug belonging to the propionic acid class was synthesized in 1968. Rapid absorption, simple metabolism, faster blood brain barrier crossing and high antinociceptive activity are the features responsible for its high use. But, free acidic moiety present in its structure is the major factor that declines its popularity by causing various gastric side effects. Many researchers have chemically modified this drug with the aim to discover an improved and safe NSAID candidate or a new drug with altered activity. We thoroughly searched the literature and found that during the period 2004-2016, more than fifty reports are available on chemical modification of ketoprofen. Along with this, many patents involving chemical modification of ketoprofen have also been reported. However, it was very surprising to note that there are only a few review articles available covering only its pharmacological and clinical properties. There is no review article available covering the chemistry part of ketoprofen. This motivated us to compile the information available on ketoprofen and its derivatives. The purpose of this article is to present an updated review about this topic.

Methods: We thoroughly searched the peer reviewed research literature and compiled all such reportings (2004 onwards) for the benefit of researchers who further want to work on ketoprofen or other NSAIDs.

Results: Studies have been conducted to invent strategies to reduce the ulcerogenic properties of ketoprofen and in the course of time, its modified and improved derivatives have been synthesized in search of safer NSAIDs. Along with the aim of reducing the gastric side-effects, researchers have also done chemical modifications in the structure of ketoprofen to improve its solubility, to alter its blood brain-barrierr permeability, to improve its pharmacodynamic profile and to get derivatives possessing antioxidant, antiviral, anticancer and immunomodulatory activities.

Conclusion: The findings of the review confirm that chemical modifications of ketoprofen decrease ulcer producing side effect while maintaining its desirable actions. Some derivatives were also found to possess better activity profile compared to the parent drug.

Background: The higher risk of diabetic nephropathy (DN) leads to end stage renal diseases worldwide, which is associated with chronic inflammation. Currently, the available treatments are limited, lack of efficacy and safety. Therefore, we are in need of novel targets and advanced treatments to reduce the necessity for the renal replacement therapy and burden of this disease management.

Object/Methods: In this review, we performed through an inflammatory mechanism that contribute to DN, will provide a key point to the finding off novel therapeutic agents. In addition, we discuss the current anti-inflammatory drugs, an alternative approach of seaweed polysaccharides and also exploring the future perspective of anti-inflammatory natural seaweed compounds. Currently, seaweeds are taking majority of attention from scientists for targeting the various diseases. This will become a more significant part of the pipeline and alternate medicines for anti-inflammatory and chronic diseases.

Conclusion: The potential benefits of natural seaweed novel compounds in inhibiting inflammatory pathways would be useful for the prevention of diabetic nephropathy. Thus, this therapy manifests the clinical benefits of these compounds in the near future.

Inhibition of Aβ(1-42)Oligomerization, Fibrillization and Acetylcholinesterase Activity by Some Anti-Inflammatory Drugs: An in vitro Study by Hamendra S. Parmar, Anshul Assaiya, Renuka Agrawal, Shalini Tiwari, Iram Mufti, Neha Jain, Elangovan Manivannan, Tushar Banerjee, Anil Kumar (191-203).
Background: Number of contradictory reports are available on the effects of antiinflammatory drugs on Alzheimer's disease (AD) including beneficial, adverse and stage dependent effects. We provide insights of the effects exerted by some anti-inflammatory drugs on the chemistry of AD.

Methods: Three different doses of dexamethasone (0.015, 0.030, 0.060 μM), piroxicam (5, 7.5, 10 μM), indomethacin (1, 1.25, 1.50 μM), diclofenac (0.6, 0.8, 1.0 μM), aspirin (90, 120, 150 μM) and celecoxib (30, 45, 60 μM) were used. Rivastigmine, methylene blue and butylated hydroxyanisole were used as standard drug, oligomerization inhibitor and antioxidant, respectively. Oligomerization and fibrillization reactions were performed using Aβ1-42 peptides. Results-Indomethacin and aspirin mainly inhibited oligomerization, while rivastigmine and piroxicam inhibited fibrillization. Diclofenac and celecoxib inhibited both oligomerization and fibrillization almost equally. Dexamethasone showed poor efficiency on both the processes, but exert comparably more inhibition of oligomerization than fibrillization. Inhibition of acetylcholinesterase activity was also potent and was in the following order: celecoxib> piroxicam> diclofenac> aspirin> indomethacin> dexamethasone. Strong radical scavenging (More than 50%) activity was showed by indomethacin and aspirin for NO radicals.

Conclusion: Present study consistently revealed that anti-inflammatory drugs have potential to Modulate chemistry of AD progression. Inclusion of anti-inflammatory drugs in low doses along with routine therapies may provide therapeutically and economically more efficient therapies for AD. However, further studies are warranted, because the overall therapeutic effect seems to be the function of stage of disease, dose of drug, main underlying mechanism of action(s).

Background: Flunarizine dihydrochloride (FHC) is used for the prophylaxis to migraine. Flunarizine has solubility problems which is practically insoluble in water and alcohol. Nanoemulsion is the approach to increase the solubility of the insoluble drugs. Nanoemulsions of FHC was prepared which can be given through the alternate route such as nasal drug delivery for migraine.

Objective: In this research work the solubility of the poorly soluble FHC was successfully improved by preparing it as a nano emulsion. Nanoemulsions can pass through the biological membrane easily so it can be delivered through nasal mucosa by which it may provide a quicker onset of action. The currently available dosage forms are in the form of tablet.

Methods: The formulations were prepared by using Glycerl Monostearate (GMS), Tween 80 as surfactant and PEG 400: Ethanol as co-surfactant in the distilled water. Nanoemulsions were prepared by step by step procedure. The prepared nanoemulsions were analyzed preliminarily by Master Sizer followed by Zeta Sizer by using the technique Dynamic Photon Correlation Spectroscopy. The best nanoemulsion was subjected to Zeta Potential study. The TEM analysis was carried out on the best formulation to gain the detailed information about the formulation.

Results: The best formulation was selected based on the physical appearance, homogenecity of the preparation, Preliminary Master Sizer analysis report, Secondary Zeta Sizer analysis report with Zeta Potential and TEM. The best formulation demonstrated the size in nano range with improved solubility.

Conclusion: The FHC nano emulsion was prepared successfully which improved the solubility of the drug. The drug release study on simulated nasal fluid revealed that the preparation is suitable to be delivered through the nasal route.

Synthesis, Characterization and Comparison of Local Analgesic, Anti-Inflammatory, Anti-Ulcerogenic Activity of Copper and Zinc Complexes of Indomethacin by Abhijit Sukul, Saikat Kumar Poddar, Sanjana Haque, Sajal Kumar Saha, Sreedam Chandra Das, Zobaer Al Mahmud, S. M. Abdur Rahman (221-233).
Background: Non-steroidal anti-inflammatory drugs (NSAID) exert gastrointestinal upset by inhibiting mucosal cyclooxygenase (COX) activity and complexation technique with metals has been adopted to overcome this drawback.

Objective: The study aimed to overcome the gastrointestinal side effects associated with indomethacin treatment by synthesizing copper (Cu) and zinc (Zn) complexes of indomethacin along with assessing potential pharmacological effects of these complexes.

Method: The characterization of synthesized complexes was done by FT-IR, XRD, UV-Vis, Atomic Absorption Spectroscopy (AAS) and Differential Scanning Calorimetry (DSC). Biological properties as local analgesic activity, anti-inflammatory activity and antiulcerogenic activity were evaluated following radiant heat tail flick, inhibition of rat hind paw edema and inhibition of NSAID induced gastroenteropathy method respectively.

Results: 0.3 ml of indomethacin-copper complex demonstrated prominent analgesia at 25 µg/ml dose and 0.3 ml of indomethacin-zinc complex, after 30, 60 and 90 minutes of oral administration, shown significant local analgesia at 25, 50 and 100 µg/ml dose. In antiinflammatory activity assay, indomethacin-copper exhibited significant inhibition at 20 mg/kg dose after 2nd, 3rd and 4th hour of administration whereas indomethacin-zinc illustrated significant inhibition at 10 mg/kg dose after 2nd, 3rd and 4th hour of administration. Anti-ulcerogenic activity study of the complexes exhibited no macroscopic damage to the stomach and intestine, except minor microscopic damage.

Conclusion: In view of the results, the copper and zinc complexes of indomethacin may be used as better substitutes of the parent indomethacin owing to their minimal side effects with additional pharmacological effects.