The pharmacokinetic study on the mechanism of toxicity attenuation of rhubarb total free anthraquinone oral colon-specific drug delivery system.

Abstract Rhubarb is commonly used as laxatives in Asian countries, of which anthraquinones are the major active ingredients, but there are an increased number of concerns regarding the nephrotoxicity of anthraquinones. In this study, we compared the pharmacokinetic characteristics of rhubarb anthraquinones in rats after orally administered with rhubarb and rhubarb total free anthraquinone oral colon-specific drug delivery granules (RTFA-OCDD-GN), and then explained why these granules could reduce the nephrotoxicity of anthraquinones when they produced purgative efficacy. A sensitive and reliable high performance liquid chromatography (HPLC) method has been fully validated for simultaneous determination of the five active components of rhubarb, and successfully applied to investigate and compare the remarkable differences in pharmacokinetic study of rhubarb anthraquinones after orally administered with rhubarb and RTFA-OCDD-GN. The results showed that, compared with rhubarb group, the AUC, C max , t 1/2z and V z/F of aloe-emodin, rhein, emodin and chrysophanol in rats receiving the RTFA-OCDD-GN were significantly decreased, and the T max of the four analytes was prolonged. Moreover, the T max of rhein, the C max of chrysophanol and emodin all have significant differences (P