In vivo antioxidant action of a lignan-enriched extract of Schisandra fruit and an anthraquinone-containing extract of Polygonum root in comparison with schisandrin B and emodin

The in vivo antioxidant action of a lignan-enriched extract of the fruit of Schisandra chinensis (FS) and an anthraquinone-containing extract of the root of Polygonum multiflorum (PME) was compared with their respective active constituents schisandrin B (Sch B) and emodin by examining their effect on hepatic mitochondrial glutathione antioxidant status in control and carbon tetrachloride (CCl4)-intoxicated mice. FS and PME pretreatments produced a dose-dependent protection against CCl4 hepatotoxicity, with the effect of FS being more potent. Pretreatment with Sch B, emodin or alpha-tocopherol (alpha-Toc) also protected against CCl4 hepatotoxicity, with the effect of Sch B being more potent. The extent of hepatoprotection afforded by FS/Sch B and PME/ emodin pretreatment against CCl4 toxicity was found to correlate well with the degree of enhancement in hepatic mitochondrial glutathione antioxidant status, as evidenced by increases in reduced glutathione level and activities of glutathione reductase, glutathione peroxidase as well as glutathione S-transferases, in both control and CCl4-intoxicated mice. alpha-Toc, which did not enhance mitochondrial glutathione antioxidant status, seemed to be less potent in protecting against CCl4 hepatotoxicity. The ensemble of results indicates that FS/PME produced a more potent in vivo antioxidant action than alpha-Toc by virtue of their ability to enhance hepatic mitochondrial glutathione antioxidant status and that the differential potency of FS and PME can be attributed to the difference in in vivo antioxidant potential between Sch B and emodin.