Potent Procoagulant and Platelet Aggregation Inducing Serine Protease from Tridax procumbens Extract

Background: Tridax procumbens extract (TPE) has been widely used in tribal/folk medicine to stop bleeding and to enhance wound healing process. Based on its traditional medicinal importance, the TPE is evaluated for its possible role in blood coagulation cascade. Objective: This study has been conducted to evaluate the TPE for the presence of protease associated with fibrino (geno) lytic, collagenolytic properties, and its action on blood coagulation cascade and platelet aggregation to substantiate its procoagulant nature. Materials and Methods: The TPE was analyzed in vitro for proteolytic, fibrinogenolytic, and collagenolytic activity. It was also analyzed for its effect on blood coagulation and platelet aggregation. In vivo studies have been conducted for hemorrhagic and edema inducing activity. Results: A non-toxic serine protease having procoagulant property associated with fibrino (geno) lytic, collagenolytic (both type I and type IV), and platelet aggregation inducing was identified and evaluated from TPE. The TPE decreased the clotting time of human plasma as evaluated by recalcification time and partial thromboplastin time by 19.8 and 1.53 folds, respectively. This suggests its procoagulant nature. TPE also enhanced the adenosine diphosphate‑/epinephrine‑induced platelet aggregation by 1.35 and 1.38 folds, respectively. Conclusion: The TPE serine protease is a non-toxic procoagulant with fibrino (geno) lytic and collagenolytic activities and induces platelet aggregation. Further, isolation and characterization of active molecule in TPE will allow us to exploit the pharmacological potential of TPE on coagulation cascade.