Introduction: Aqueous extract of Lagerstroemia speciosa (EALS) (Lythraceae) is widely used to treat diabetes. This plant has been shown an in vitro thrombolytic activity that indicates its potential to prevent the formation of blood clots in vivo. Thus, this study was undertaken to evaluate the antithrombotic and antihemolytic effects of EALS.
Methods: Rats of both sexes (200 ± 5 g) were divided into five groups of six animals. Each group received orally distilled water, EALS (250, 500, 1000 mg/kg), and acetylsalicylic acid (100 mg/kg) for five days. After treatment, the FeCl3-induced arterial thrombus formation method was used to determine occlusion time. A coagulometer was used to detect activated partial thromboplastin time (aPTT) and prothrombin time (PT). Rabbit blood was used to determine clot lysis activity in vitro and antihemolytic activity using the 2,2-azobis hydrochloride (2-methylpropionamidine) (AAPH) method.
Results: EALS increased the occlusion time in a dose-dependent manner. At the dose of 1000 mg/kg, EALS increased the occlusion time significantly, from 4.59 ± 2.45 minutes to 15.52 ± 2.38 minutes (P<0.01). At high concentrations (1-4 mg/mL), EALS showed a significant increase in aPPT and PT (P<0.05). Streptokinase and EALS (4 mg/mL) induced significant clot lysis with percentage values of 78.48 ± 2.2 % and 49.5 ± 1.53 %, respectively (P<0.001). EALS inhibited AAPH-induced hemolysis.
Conclusion: EALS exhibited antithrombotic and antihemolytic activities. The antithrombotic property of the plant could be attributed to its anticoagulant and thrombolytic activities. Regular consumption of L. speciosa leaves may prevent or treat thrombotic diseases.