Bioassay-guided identification of antithrombotic compounds from Cnidoscolus aconitifolius (Mill.) I. M. Jhonst.: molecular docking, bioavailability, and toxicity prediction.

Cardiovascular diseases (CVDs) are the leading cause of death worldwide. Conventional antithrombotic therapy has reported hemorrhagic accidents. Ethnobotanical and scientific reports point to Cnidoscolus aconitifolius as an antithrombotic adjuvant. Previously, C. aconitifolius leaves ethanolic extract displayed antiplatelet, anticoagulant, and fibrinolytic activities. This work aimed to identify compounds from C. aconitifolius with in vitro antithrombotic activity through a bioassay-guided study. Antiplatelet, anticoagulant, and fibrinolytic tests guided the fractionation. Ethanolic extract was subjected to a liquid-liquid partitioning, followed by vacuum liquid, and size exclusion chromatography to obtain the bioactive JP10B fraction. The compounds were identified through UHPLC-QTOF-MS, and their molecular docking, bioavailability, and toxicological parameters were determined computationally. Kaempferol-3-O-glucorhamnoside and 15(S)-HPETE were identified; both showed affinity for antithrombotic targets, low absorption, and safety for human consumption. Further in vitro and in vivo evaluations will better understand their antithrombotic mechanism. This bioassay-guided fractionation demonstrated that C. aconitifolius ethanolic extract has antithrombotic compounds.Communicated by Ramaswamy H. Sarma.

Flavonoids as a therapeutical option for the treatment of thrombotic complications associated with COVID-19.

The SARS-CoV-2 outbreak has been one of the largest public health crises globally, while thrombotic complications have emerged as an important factor contributing to mortality. Therefore, compounds that regulate the processes involved in thrombosis could represent a dietary strategy to prevent thrombotic complications involved in COVID-19. In August 2022, various databases were consulted using the keywords "flavonoids", "antiplatelet", "anticoagulant", "fibrinolytic", and "nitric oxide". Studies conducted between 2019 and 2022 were chosen. Flavonoids, at concentrations mainly between 2 and 300 µM, are capable of regulating platelet aggregation, blood coagulation, fibrinolysis, and nitric oxide production due to their action on multiple receptors and enzymes. Most of the studies have been carried out through in vitro and in silico models, and limited studies have reported the in vivo and clinical effect of flavonoids. Currently, quercetin has been the only flavonoid evaluated clinically in patients with COVID-19 for its effect on D-dimer levels. Therefore, clinical studies in COVID-19 patients analyzing the effect on platelet, coagulant, fibrinolytic, and nitric oxide parameters are required. In addition, further high-quality studies that consider cytotoxic safety and bioavailability are required to firmly propose flavonoids as a treatment for the thrombotic complications implicated in COVID-19.

Antithrombotic Study and Identification of Metabolites in Leaf Extracts of Chaya [Cnidoscolus aconitifolius (Mill.) I.M. Johnst.].

In Mexico, Cnidoscolus aconitifolius (chaya) has been used to treat cardiovascular diseases (CVD). Because CVD are the number one cause of mortality, chaya use has become a health strategy. The aim of this study was to evaluate the antithrombotic activity and identify the metabolites in the most active extract. Aqueous (Aq), ethanolic (EtOH), acetonic (An), ethyl acetate (AcOEt), diethyl ether (Et2O), and hexanic (Hx) extracts were obtained. Platelet aggregation, phospholipase A2, prothrombin time (PT), activated partial thromboplastin time (aPTT), and clot lysis were evaluated. Metabolites were identified by gas chromatography-mass spectrometry (GC-MS). EtOH showed the greatest inhibition of platelet aggregation and phospholipase A2. Ac had the greatest effect on PT and aPTT. AcOEt had the greatest effect on clot lysis. EtOH, with the highest potential, was analyzed by GC-MS; fatty acids and triterpenes were identified. Thus, EtOH showed greater antiplatelet activity and other extracts showed moderate activity. This is a preliminary antithrombotic study. Future research will allow the development of nutraceuticals or functional ingredients for the prevention and treatment of thrombosis.