Phytochemical analysis and thrombolytic profiling of Costus afer stem fractions

Background The most commonly occurring mechanism driving ischemic heart disease, ischemic stroke, and myocardial infarction is thrombosis. It is normally characterized by platelet activation and aggregation. Thrombolytics have been used in the treatment of several forms of thrombosis, but their adverse effects have limited their usefulness. Thus, there is a need to develop alternatives from medicinal plants known to possess antithrombotic activity such as Costus afer. Results The phytochemical evaluations indicated the presence of flavonoids, alkaloids, cardiac glycosides, tannins, terpenoids, and saponins. The antithrombotic profiling showed that streptokinase had the highest percentage clot lysis, followed by ethylacetate fraction of the extract, which was higher than aspirin and other fractions of the extract. Conclusion The present findings show that C. afer stem extract and various fractions possess antithrombotic activities. However, further studies are needed to characterize the antithrombotic bioactive compounds present in the different fractions that are responsible for the activities.

Antithrombotic Activity of Heparinoid G2 and Its Derivatives from the Clam Coelomactra antiquata

Clam heparinoid G2 (60.25 kDa) and its depolymerized derivatives DG1 (24.48 kDa) and DG2 (6.75 kDa) prepared from Coelomactra antiquata have been documented to have excellent fibrinolytic and anticoagulant activity. In this study, to further explore the antithrombotic activity of G2, DG1 and DG2, azure A, sheep plasma, and clot lytic rate assays were used to determine their anticoagulant and thrombolytic activity in vitro. The results indicated that the anticoagulant titer of G2 was approximately 70% that of heparin and the thrombolytic activity of DG2 was greater than G2, DG1, and heparin activities. Moreover, in a carrageenan-induced venous thrombosis model, oral administration of G2 and DG1 each at 20 mg/kg and 40 mg/kg for 7 days significantly reduced blacktail thrombus formation, increased tissue-type plasminogen activator, fibrin degradation products, and D-dimer levels, decreased von Willebrand factor and thromboxane B2 levels, and restored phylum and genus abundance changes of intestinal bacteria. DG2 had no antithrombotic effect. At 20 mg/kg, G2, DG1, and heparin had comparable antithrombotic activities, and DG1 at 40 mg/kg had more muscular antithrombotic activity than G2. Thus, DG1 could be an antithrombotic oral agent owing to its more robust antithrombotic activity and lower molecular weight.

Synthesis of novel 1,3,4-oxadiazole derivatives of nicotinic acid and its in-vitro antithrombotic activity

The pharmacological characteristics of azole are diverse. Only a few medications can reduce the risk of clot formation, and they all have serious side effects. At present time there has to be more focus on to cure this type of complication beacause due to environmental, emotional, physical, other biological incidents are much related to this condition. Resistance has developed to existing medications, prompting the implementation of novel medications with a greater activity profile. The synthesis of a 1,3,4-oxadiazole derivative from nicotinic acid as well as its antithrombotic activity is described in this paper.

Pharmacological Activities and Mechanisms of Hirudin and Its Derivatives - A Review

Hirudin, an acidic polypeptide secreted by the salivary glands of Hirudo medicinalis (also known as “Shuizhi” in traditional Chinese medicine), is the strongest natural specific inhibitor of thrombin found so far. Hirudin has been demonstrated to possess potent anti-thrombotic effect in previous studies. Recently, increasing researches have focused on the anti-thrombotic activity of the derivatives of hirudin, mainly because these derivatives have stronger antithrombotic activity and lower bleeding risk. Additionally, various bioactivities of hirudin have been reported as well, including wound repair effect, anti-fibrosis effect, effect on diabetic complications, anti-tumor effect, anti-hyperuricemia effect, effect on cerebral hemorrhage, and others. Therefore, by collecting and summarizing publications from the recent two decades, the pharmacological activities, pharmacokinetics, novel preparations and derivatives, as well as toxicity of hirudin were systematically reviewed in this paper. In addition, the clinical application, the underlying mechanisms of pharmacological effects, the dose-effect relationship, and the development potential in new drug research of hirudin were discussed on the purpose of providing new ideas for application of hirudin in treating related diseases.

Are all wines made from various grape varieties beneficial in the prevention of myocardial infarction and stroke?

Aim: Epidemiologic studies support the assumption (French paradox hypothesis) that drinking red wine is beneficial in the prevention of cardiovascular diseases. Our recent works however cast doubt on such claim. Earlier we have shown that the antithrombotic activity of various fruits and vegetables mainly depends on their varieties. For this reason, several varieties of red and white grapes were tested for antithrombotic effect in animal experiments. Results: Antithrombotic effect of 45 red and white grape varieties were assessed in the present study. Out of the 45, one red grape variety showed antithrombotic effect, while the majority of red and white grape varieties enhanced thrombosis. Conclusion: Most red and white grape varieties enhanced thrombotic activity of blood.

IN VITRO ANTIPLATELET AND ANTICOAGULANT ACTIVITY OF INDIGENOUS VEGETABLES FROM SOUTHERN THAILAND

Objective: Epidemiological studies have indicated that diets rich in fruits and vegetables help reduce the risk of cardiovascular diseases (CVDs).However, data about the antithrombotic activity of local vegetables is rare. The objective of this study was to evaluate antiplatelet and anticoagulantactivity in indigenous vegetables with high phenolic compounds collected from Southern Thailand.Methods: Five selected indigenous vegetables were crudely extracted by distilled water and 80% methanol. The extracts were screened for in vitroantiplatelet and anticoagulant activity at a concentration of 10 μg/μl. The antiplatelet activity was measured by inhibition of platelet adhesion tocollagen and thrombin-induced platelet aggregation, while the anticoagulant activity was assessed by the prothrombin time (PT) and activated partialthromboplastin time (APTT) tests.Results: Among the selected vegetables, the extracts of mon-pu (Glochidion perakense Hook.f.) and young cashew leaves (Anacardium occidentale L.)showed high antithrombotic properties. The highest antithrombotic activity was observed in the methanolic extract of mon-pu, which showed92.79±0.78% of platelet adhesion inhibition, 102.9±1.53% of platelet aggregation inhibition, and a prolonged APTT assay (48.92±0.94 s). Theprolonged APTT but normal PT results suggested that the extract could affect factors VIII, IX, XI, and XII of the intrinsic coagulation pathway.Conclusion: Our findings demonstrated antiplatelet and anticoagulation properties of indigenous vegetables from Southern Thailand. The multipotentialeffects of mon-pu extracts on antithrombosis evidently suggest that mon-pu can be considered as an excellent nutraceutical option in theprevention of thrombosis-related CVDs caused by different mechanisms.