Chemical characterization, anti-benign prostatic hyperplasia effect and subchronic toxicity study of total flavonoid extract of Pteris multifida.

The decoction of Pteris multifida had been applied to attenuate symptoms of benign prostatic hyperplasia in Chinese folk medicine. In this study, the total flavonoid extract of Pteris multifida was processed at first. High performance liquor chromatography and tandem mass spectrometer assay revealed 10 flavonoids as key constituents of this extract. After 60-day administration, the total flavonoid extract (180 mg/kg, i. g.) decreased the prostate index in mice of benign prostatic hyperplasia apparently. Immunohistochemical assay revealed inhibition of vascular endothelial growth factor expression, together with activation of transforming growth factor-beta 1 expression in the prostatic samples after administration of the extract. A 90-day subchronic toxicity test was further undertaken in male Sprague-Dawley rats, and the no-observed-adverse-effect level for the extract was 200 mg/kg body weight/day. These results revealed that the total flavonoid extract of Pteris multifida exhibited positive effect with safety, which might be applied in treatment of benign prostatic hyperplasia.