Design, Synthesis, and Docking Studies of Arylhydrazone Compounds and Evaluation of Their Platelet Aggregation Inhibitory Effect and Cytotoxicity

In view of proven antiplatelet activity of hydrazone group containing compounds, two series of hydrazone derivatives were synthesized by coupling appropriate aldehydes with phenyl hydrazine and Isonicotinic acid in the presence of distilled water and a catalytic amount of glacial acetic acid. All synthesized compounds were screened for their antiplatelet activity against induced aggregation by adenosine diphosphate (ADP) and arachidonic acid (AA). The results indicate that compounds in arylhydrazone group had shown satisfactory activity. Among them, 1-(3-methoxybenzylidene)-2-phenylhydrazine (1c), 2-methoxy-4-(2-phenylhydrazono) methyl phenol (1g), and 2-((2-phenylhydrazono) methyl)-1H-pyrrole (1h) were found to be the most potent antiplatelet compounds with IC50 less than 39 μM. Furthermore, the cell toxicity assay, (MTT test) indicates their noncytotoxic in various cell lines. None of the synthesized N-isonicotinohydrazide derivatives in this study excreted sufficient antiplatelet activity.

Sorghum Protein Extract Protects RBC from Sodium Nitrite-Induced Oxidative Stress and Exhibits Anticoagulant and Antiplatelet Activity

Introduction: Oxidative stress plays a critical role in the progression of diabetes, arthritis, cancer, eryptosis, cardiovascular disease, and thrombosis. Currently, antioxidants from natural sources are in high demand due to their beneficial role in the management of said diseases. Aim: The purpose of the study was to evaluate the protective effect of sorghum protein buffer extract (SBE) on sodium nitrite-induced oxidative stress and thrombosis. Materials and methods: Protein characterization of SBE was done using SDS-PAGE. Oxidative stress in RBC was induced using sodium nitrite (NaNO2) and the key stress markers such as lipid peroxidation (LPO), protein carbonyl content (PCC), and the level of antioxidant enzymes (SOD and CAT) were measured. The anticoagulant effect of SBE was identified by employing in-vitro plasma recalcification time, activated partial thromboplastin time (APTT), prothrombin time (PT), and in-vivo mouse tail bleeding time. SBE antiplatelet activity was examined using agonist adenosine diphosphate (ADP) and epinephrine-induced platelet aggregation. Non-toxic property of SBE was identified using in-vitro direct haemolytic, haemorrhagic, and edema forming activities using experimental mice. Results: SBE revealed similar protein banding pattern under both reduced and non-reduced conditions on SDS-PAGE. Interestingly, SBE normalized the level of LPO, PCC, SOD, and CAT in stress-induced RBCs. Furthermore, SBE showed anticoagulant effect in platelet rich plasma by enhancing the clotting time from the control 250 s to 610 s and bleeding time from the control 200 s to more than 500 s (p<0.01) in a dose dependent manner. In addition, SBE prolonged the clot formation process of only APTT but not PT. SBE inhibited the agonists ADP and epinephrine induced platelet aggregation. SBE did not hydrolyze RBC cells, devoid of edema and haemorrhage properties. Conclusions: This study demonstrates for the first time the anticoagulant, antiplatelet, and antioxidant properties of SBE. Thus, the observed results validate consumption of sorghum as good for health and well-being.

Screening of Synthetic Heterocyclic Compounds as Antiplatelet Drugs

Background: Antiplatelet drugs represent the keystone in the treatment and prevention of diseases of ischemic origin, including coronary artery disease. The current palette of drugs represents efficient modalities in most cases, but their effect can be limited in certain situations or associated with specific side effects. In this study, representatives of compounds selected from series having scaffolds with known or potential antiplatelet activity were tested. These compounds were previously synthetized by us, but their biological effects have not yet been reported. Objective: The aim of this study was to examine the antiplatelet and anticoagulation properties of selected compounds and determine their mechanism of action. Methods: Antiplatelet activity of compounds and their mechanisms of action were evaluated using human blood by impedance aggregometry and various aggregation inducers and inhibitors and compared to appropriate standards. Cytotoxicity was tested using breast adenocarcinoma cell cultures and potential anticoagulation activity was also determined. Results: In total, four of 34 compounds tested were equally or more active than the standard antiplatelet drug acetylsalicylic acid (ASA). In contrast to ASA, all 4 active compounds decreased platelet aggregation triggered not only by collagen, but also partly by ADP. The major mechanism of action is based on antagonism at thromboxane receptors. In higher concentrations, inhibition of thromboxane synthase was also noted. In contrast to ASA, the tested compounds did not block cyclooxygenase-1. Conclusion: The most active compound, 2-amino-4-(1H-indol-3-yl)-6-nitro-4H-chromene-3-carbonitrile (2-N), which is 4-5x times more potent than ASA, is a promising compound for the development of novel antiplatelet drugs.

SYNTHESIS, ANTIAGGREGATION AND ANTITROMBOTIC ACTIVITIES OF NEW DERIVATIVES OF HYDROXYBENZOIC ACIDS WITH TAURIC FRAGMENT

A high prevalence of thrombotic disorders, insufficient effectiveness or safety of antithrombotic therapy is an urgent problem of modern healthcare. The main means of preventing thrombosis is acetylsalicylic acid. Despite its long history, aspirin attracts researchers in the fields of medicinal chemistry, biology, and medicine. The development of new antiplatelet agents, including chemical modification of the acetylsalicylic acid molecule, remains relevant. Modification of the acetylsalicylic acid molecule using amino acids and obtaining their salt forms makes it possible to maintain antiplatelet or antithrombotic properties, as well as to impart additional pharmacodynamic effects. In modern science, a lot of attention is paid to the sulfur-containing amino acid taurine. An analysis of modern scientific literature revealed the protective effect of taurine in diabetes mellitus and cardiovascular diseases, liver dysfunction, gastrointestinal tract, and kidney diseases.The aim of the article is to study synthesis of new compounds, determination of their physical characteristics and assessment of their antiplatelet and antithrombotic activities in vitro and in vivo.Materials and methods. To confirm the structure of the synthesized new derivatives of hydroxybenzoic acids with a taurine fragment by the acelation method, thin layer chromatography and NMR spectra were used. In vitro studies were carried out on the model of ADP-induced platelet aggregation according to the Born G. methods modified by V.A. Gabbasov. In vivo, the studies were carried out on the model of arterial thrombosis induced by the application of iron chloride in the following groups of animals: intact, with experimental diabetes mellitus and three-year-olds; the rate of bleeding from the tail vein was also evaluated.Results. New compounds – derivatives of ortho-, meta- and para-hydroxybenzoic acids with a taurine residue – were synthesized. A procedure for the preparation of N-hydroxybenzoyl taurine compounds and their salt forms have been described; their spectral characteristics and melting points have been determined. The synthesized compounds are superior to acetylsalicylic acid in solubility and are not inferior to it in antiplatelet and antithrombotic activities. The results of the in vitro antiplatelet activity assessment in a wide concentration range from 10-4M to 10-8M, are presented. It has been revealed that the dipotassium salt of N-(2-hydroxybenzoyl)taurine exhibits a less antiplatelet activity than the dipotassium salt of N-(3-hydroxybenzoyl)taurine. The most pronounced antiplatelet activity is exhibited by the compound N-(4-hydroxybenzoyl)taurine. In in vivo experiments on the model of arterial thrombosis in 3-year-olds or animals with experimental diabetes mellitus, carotid artery thrombosis occurred faster than in young or intact animals. A single preliminary oral administration of the test compounds prolonged the time of the thrombus formation, which makes it possible to conclude that they have an antithrombotic effect. In this study, the dipotassium salt of N-(3-hydroxybenzoyl)taurine exhibits a more pronounced activity than that of acetylsalicylic acid.Conclusion. Against the background of the modeled pathologies, the studied drugs showed the expected antithrombotic activity, in terms of the severity not inferior to that found in acetylsalicylic acid.