Toxicological studies of wogonin in experimental animals.

Wogonin, one active ingredient extract from the radix of Scutellaria baicalensis Georgi, is known to possess a broad spectrum of pharmacological, medicinal and therapeutic properties, especially the anticancer activity studied recently. However, no extensive safety studies have been conducted to date. In this paper, the acute and sub-chronic toxicity of the agent were determined using albino mice and Sprague-Dawley rats as animal models. Histopathological examination and viscera parameter investigation were also carried out after autopsy. The LD(50) of wogonin administered by the intravenous injection was 286.15 mg/kg and the 95% confidence limit was 278.27-295.26 mg/kg. A long period of treatment with a high dose of wogonin (120 mg/kg) could induce heart injury in rats. These results provide a foundation for the further clinical investigation of this promising anticancer agent.