The leaves of Cassia angustifolia VAHL and Cassia acutifolia DELILE (Leguminosae), used as a potent laxative worldwide, contain several anthraquinone polyphenols. Anthraquinones have been reported to possess various beneficial bioactivities, however, they were mainly based on in vitro evidences. The information concerning the metabolic pharmacokinetics of anthraquinones in Folium Sennae decoction remained limited.
In order to understand the absorption and disposition of Folium Sennae decoction, the metabolic pharmacokinetic studies were conducted in rats. Rats were administered orally with 10 g/kg single dose and multiple dose of Folium Sennae. The serum concentration of serum samples was assayed by HPLC before and after hydrolysis with sulfatase and β-glucuronidase, respectively. The results showed that the conjugated metabolites were predominantly present in the circulation, mainly glucuronides. The free form of rhein was present but at lower concentration than the conjugation metabolites. Only trace of aloe-emodin free form was detected in serum. Comparison of pharmacokinetic parameters following single-dose and multiple-dose administrations indicated that there were no significant differences between two treatments.
In addition, to extend the result of metabolic pharmacokinetics, we investigated the effect of the serum metabolites of Folium Sennae decoction at pharmacological concentration on AAPH-induced hemolysis. The result indicated that oral administration of Folium Sennae could not exert promising free radical scavenging effect in vascular system.
