Effects of organic extracts and their different fractions of five Bangladeshi plants on in vitro thrombolysis

Background: The increasingly high incidence of ischemic stroke caused by thrombosis of the arterial vessels is one of the major factors that threaten people's health and lives in the world. The present treatments for thrombosis are still unsatisfactory. Herbal preparations have been used since ancient times for the treatment of several diseases. The aim of this study was to investigate whether herbal preparations possess thrombolytic activity or not. Methods: An in vitro thrombolytic model was used to check the clot lysis effect of the crude extracts and fractions of five Bangladeshi plant viz., Trema orientalis L., Bacopa monnieri L., Capsicum frutescens L., Brassica oleracea L. and Urena sinuata L. using streptokinase as a positive control and water as a negative control. Briefly, venous blood drawn from twenty healthy volunteers was allowed to form clots which were weighed and treated with the test plant materials to disrupt the clots. Weight of clot after and before treatment provided a percentage of clot lysis. Results: Using an in vitro thrombolytic model, different fractions of five Bangladeshi medicinal plants namely Trema orientalis, Bacopa monnieri, Capsicum frutescens, Brassica oleracea and Urena sinuata showed various range of clot lysis activity. Chloroform fractions of Trema orientalis, Bacopa monnieri, Capsicum frutescens, Brassica oleracea and Urena sinuata showed highest significant (P < 0.05 and P < 0.001) clot lysis activity viz., 46.44 +/- 2.44%, 48.39 +/- 10.12%, 36.87 +/- 1.27%, 30.24 +/- 0.95% and 47.89 +/- 6.83% respectively compared with positive control standard streptokinase (80.77 +/- 1.12%) and negative control sterile distilled water (5.69 +/- 3.09%). Other fractions showed moderate to low clot lysis activity. Order of clot lysis activity was found to be: Streptokinase > Chloroform fractions > Methanol (crude) extract > Hydro-methanol fractions > Ethyl acetate fractions > n-hexane fractions > Water. Conclusions: Our study suggests that thrombolytic activity of Trema orientalis, Bacopa monnieri and Urena sinuata could be considered as very promising and beneficial for the Bangladeshi traditional medicine. Lower effects of other extracts might suggest the lack of bio-active components and/or insufficient quantities in the extract. In vivo clot dissolving property and active component(s) of Trema orientalis and Bacopa monnieri for clot lysis could lead the plants for their therapeutic uses. However, further work will establish whether or not, chloroform soluble phytochemicals from these plants could be incorporated as a thrombolytic agent for the improvement of the patients suffering from atherothrombotic diseases.