Antithrombotic and antiplatelet activities of Soshiho-tang extract

BACKGROUND Soshiho-tang (SH; Chinese name, Xiao-Chai-Hu-Tang; Japanese name, Shosaiko-to) is a traditional Korean, Chinese, and Japanese medicine, which has been used to treat various conditions, including hepatitis, liver cirrhosis, and chronic and acute liver disease. SH consists of seven herbal components, of which Scutellaria baicalensis Georgi and Zingiber officinale Roscoe, are reported to have antithrombotic and antiplatelet activities. We investigated the antithrombotic activity of SH, including S. baicalensis and Z. officinale, as an integrative therapy. METHODS To identify the antithrombotic activity of SH, we used a FeCl3-induced thrombus formation model. The mechanism of SH-mediated antithrombotic activity was assessed by determining platelet aggregation and coagulation times ex vivo, washed platelet aggregation, serotonin secretion, and thromboxane B2 formation. RESULTS SH prolonged the occlusion time of thrombus formation when applied in a FeCl3-induced thrombus formation model. SH also inhibited collagen-induced platelet aggregation ex vivo in a concentration-dependent manner; however, it did not affect coagulation. Hence, to identify the antiplatelet effect of SH, we investigated washed platelet aggregations in vitro. SH significantly inhibited various agonist-induced platelet aggregations, and it completely inhibited serotonin secretion and thromboxane B2 formation. CONCLUSIONS The findings suggest that SH inhibited FeCl3-induced thrombus formation through antiplatelet activity, including inhibition of platelet aggregation, and serotonin and TXB2 production. Thus, SH may be useful as an integrative herbal formula for the treatment of thrombosis.