Reyes Laguna

Effects of cis-resveratrol on inflammatory murine macrophages: antioxidant activity and down-regulation of inflammatory genes.

This study investigated for the first time the effects of the cis isomer of resveratrol (c‐RESV) on the responses of inflammatory murine peritoneal macrophages, namely on the production of reactive oxygen species (ROS) and reactive nitrogen species (RNS) during the respiratory burst; on the biosynthesis of other mediators of inflammation such prostaglandins; and on the expression of inflammatory genes such as inducible nitric oxide synthase (NOS)‐2 and inducible cyclooxygenase (COX)‐2. Treatment with 1–100 μM c‐RESV significantly inhibited intracellular and extracellular ROS production, and c‐RESV at 10–100 μM significantly reduced RNS production. c‐RESV at 1–100 μM was ineffective for scavenging superoxide radicals (O2•−), generated enzymatically by a hypoxanthine (HX)/xanthine oxidase (XO) system and/or for inhibiting XO activity. However, c‐RESV at 10–100 μM decreased nicotinamide adenine dinucleotide/nicotinamide adenine dinucleotide phosphate (NADH/NADPH) oxidase activity in macrophage homogenates. c‐RESV at 100 μM decreased NOS‐2 and COX‐2 mRNA levels in lipopolysaccharide (LPS) interferon gamma (IFN‐γ)‐treated macrophages. At 10–100 μM, c‐RESV also significantly inhibited NOS‐2 and COX‐2 protein synthesis and decreased prostaglandin E2 (PGE2) production. These results indicate that c‐RESV at micromolar concentrations significantly attenuates several components of the macrophage response to proinflammatory stimuli (notably, production of O2•− and of the proinflammatory mediators NO• and PGE2).

Pyridazines. Part XXIX: synthesis and platelet aggregation inhibition activity of 5-substituted-6-phenyl-3(2H)-pyridazinones. Novel aspects of their biological actions.

A series of 6-phenyl-3(2H)-pyridazinones with a diverse range of substituents in the 5-position have been prepared and evaluated in the search for new antiplatelet agents. A significant dependence of the substituent on the inhibitory effect has been observed. The pharmacological study of these compounds confirms that modification of the chemical group at position 5 of the 6-phenyl-3(2H)-pyridazinone system influences both variations in the antiplatelet activity and the mechanism of action.

8‐Substituted 3‐Arylcoumarins as Potent and Selective MAO‐B Inhibitors: Synthesis, Pharmacological Evaluation, and Docking Studies

Neurodegenerative disorders are becoming more prevalent given the increase in the aging population. This has inspired active research in the development of new drugs that could mark an important advance in the treatment of complex diseases such as Alzheimer′s and Parkinson′s. With the aim of finding new MAO‐B‐selective inhibitors, we report the synthesis, in vitro evaluation, and docking simulation of a new series of 3‐arylcoumarins variously substituted at the 8‐position. Most of the studied compounds show high affinity and selectivity for the hMAO‐B isoform, with IC50 values in the low micro‐ to nanomolar range. Some of them have greater hMAO‐B inhibitory activity and selectivity than the reference compound, selegiline. Compounds 7 and 8 are the most active of this series, with compound 8 being fivefold more potent against MAO‐B and severalfold more selective than selegiline. Docking experiments were carried out with hMAO‐B crystal structures, providing new information about the enzyme–inhibitor interaction and the potential therapeutic application of the new 8‐substituted 3‐arylcoumarins.

AM1 theoretical study, synthesis and biological evaluation of some benzofuran analogues of anti-inflammatory arylalkanoic acids

Using the semi-empirical quantum-mechanical method AM1, the molecular geometries of the arylalkanoic acids, indomethacin, naproxen and ibuprofen, were optimized and their frontier orbital charge distributions evaluated. Then, these molecular parameters were compared in order to identify structure-activity relationships and, on the basis of these, four benzofuran-3-acetic acids were designed as potential non-steroidal anti-inflammatory agents, and rapidly synthesized by a novel and easily generalized route. Notwithstanding the structural similarities between the synthesized compounds and the anti-inflammatory arylalkanoic acids, these compounds did not appreciably inhibit human platelet cyclooxygenase in vitro.

Pyridazines. Part 28: 5-Alkylidene-6-phenyl-3(2H)-pyridazinones, a New Family of Platelet Aggregation Inhibitors §

The synthesis and anti-platelet activity of several 5-alkylidene-6-phenyl-3(2H)-pyridazinones are described. The most active compounds are those that contain oxygenated functions (COOR, COMe) on the alkylidene fragment (6a, 6b and 6c).

New pyridazinone derivatives with vasorelaxant and platelet antiaggregatory activities

New 6-substituted and 2,6-disubstituted pyridazinone derivatives were obtained starting from easily accessible alkyl furans by using oxidation with singlet oxygen to give 4-methoxy or 4-hydroxybutenolides, key intermediates of this synthetic strategy. The new pyridazinone derivatives have been studied as vasorelaxant and antiplatelet agents. Analysis of biological data revealed the silyl ethers (4a-i) and N,O-dibenzyl derivatives (6g-i) as the most active compounds.

Bioadhesive emulsions for control release of progesterone resistant to vaginal fluids clearance

The aim of this study is to propose that mucoadhesive vaginal emulsions can be able to resist the clearance effect of vaginal fluid and to have an effective control release of progesterone. With this goal, silicon derivative, cyclomethicone pentamer, was selected as the bioadhesive and water resistant material. In order to obtain a system which is insensitive to the dilution of aqueous fluids, water in silicone (W/S) emulsions were prepared and different proportions of cyclomethicone as well as 8% or 15% w/w of progesterone were employed. The rheological, mechanical and mucoadhesive properties of emulsions were characterized and the drug release was measured for each formulation. Mucoadhesive behavior was determined and the influence of simulated vaginal fluid (SVF) at bioadhesion was assessed using three commercial mucoadhesive vaginal gels (Crinone(®), K-Y jelly(®) and Zidoval(®)) as the bioadhesive references. All assayed emulsions have good rheological and mechanical properties and their consistence and viscosity increase when the proportion of the internal phase increases. Related to mucoadhesion, in the absence of SVF, W/S emulsions showed similar bioadhesive levels like the commercial formulations. However, in the presence of SVF, W/S emulsions are able to keep their mucoadhesive properties while the marketed references drastically lose their consistency and adherence to the vaginal mucosa. Drug release profiles from W/S emulsion show that progesterone is released with pseudo-order zero kinetics and a constant release rate is maintained for at least two weeks. The results of the in vivo studies developed in rats show that after a single vaginal administration, bioadhesive W/S emulsions increase the uterine tissue progesterone levels in young and postmenopausal rats. Moreover in postmenopausal rats, they provide high uterine levels of progesterone compared to the bioadhesive-marketed gel used as a reference. Therefore, W/S emulsions have an interesting potential as bioadhesive vaginal delivery systems for drug administration.

History and therapeutic use of MAO-A inhibitors: a historical perspective of mao-a inhibitors as antidepressant drug.

Since the first generation of MAO inhibitors was developed, more than fifty years ago, this family of drugs has been ups and downs over the last decades. Actually, interest in MAO inhibitors is reviving and the emergence of new advances in the rational design of molecules and new techniques to predict the in vivo behavior has encouraged the research for new drugs with therapeutic potential in this area. The classic MAOIs have been widely used as antidepressants during the two decades after its introduction in clinic. Based on observations made on MAO inhibition by these drugs, it has been postulated hypothesis that have contributed to a better understanding of the mechanism and management of depressive disorders. However, exaggerated concerns about food and drug interactions relegated these drugs from the pharmaceutical landscape. The correct interpretation and the contextualization of side effects and the recent research findings, in which MAO selective inhibitors appear as promising agents in the treatment of emerging and high prevalence diseases, are placing these drugs again into the scientific and pharmacological focus.

3‐Amidocoumarins as Potential Multifunctional Agents against Neurodegenerative Diseases

Monoamine oxidase (MAO) generates reactive oxygen species (ROS), which cause neuronal cell death, causing neurodegeneration. Agents that are able to concurrently inhibit MAO and scavenge free radicals represent promising multifunctional neuroprotective agents that could be used to delay or slow the progression of neurodegenerative diseases. In this work, variously substituted 3‐amidocoumarins are described that exert neuroprotection in vitro against hydrogen peroxide in rat cortical neurons, as well as antioxidant activity in a 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH⋅) radical scavenging assay. Selective and reversible inhibitors of the MAO‐B isoform were identified. Interestingly, in the case of the 3‐benzamidocoumarins, substitution at position 4 with a hydroxy group abolishes MAO‐B activity, but the compounds remain active in the neuroprotection model. Further evaluation of 3‐heteroarylamide derivatives indicates that it is the nature of the heterocycle that determines the neuroprotective effects. Evaluation in a parallel artificial membrane permeability assay (PAMPA) highlighted the need to further improve the blood–brain barrier permeability of this compound class. However, the compounds described herein adhere to Lipinski′s rule of five, suggesting that this novel scaffold has desirable properties for the development of potential drug candidates.

Anti‐aggregant effects on human platelets of the crude aqueous extract and polar fractions of the microalga Dunaliella tertiolecta

The crude aqueous extract of the microalga Dunaliella tertiolecta was found to have strong inhibitory effects on the aggregation of human platelets induced by thrombin, arachidonic acid and ionomycin. The extraction of the crude aqueous extract with iPrOH and posterior fractionation with solvents of increasing polarity, concentrated the activity in the more polar fractions.