Understanding the effect of anthocyanins extracted from purple sweet potatoes on alcohol-induced liver injury in mice.

Anthocyanins as antioxidants are potential to protect liver from alcoholic damage, but might be pro-oxidants under certain conditions. In this study, twelve purple sweet potatoes anthocyanins (PSPA) were isolated and their effects on alcohol-induced liver injury were studied. These PSPA were rich in cyanidin derivatives and fed to male C57BL/6 mice as colorants in alcoholic drink with low, median, or high dosages PSPA i.e. 50, 100, or 300 mg/kg·BW·d. Compared to the alcohol group, the median-dose PSPA showed a clear improvement in the liver indexes/histology, serum ALT level, oxidative stress status, and even a recovery to the normal level, however the high dose PSPA promoted the liver injury via a pro-oxidant effect, as reflected by increased malondialdehyde (MDA) content and decreased GSH level. The results suggested that cyanidin derivatives with an ortho-hydroxyl structure on B-ring might promote the oxidative stress of alcohol-induced liver injury at high doses as a pro-oxidant.