Differential protective effects of polyphenol extracts from apple peels and fleshes against acute CCl4-induced liver damage in mice

The present study reports the phenolic profiles and antioxidant and hepatoprotective properties of Red Fuji apple peel polyphenolic extract (APP) and its flesh polyphenolic extract (AFP) against CCl4-induced acute hepatic damage in mice. It was found that the polyphenol and flavonoid contents of APP were significantly higher than those of AFP. APP was shown to exhibit stronger in vitro antioxidant activities than AFP in a dose-dependent manner. Administration of APP at 250 and 500 mg per kg bw to mice ahead of CCl4 injection was further shown to exhibit stronger in vivo protective effects than those of AFP and could observably antagonize the CCl4-induced increase in serum alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase activities and hepatic malondialdehyde levels, and prevent the CCl4-caused decrease in antioxidant superoxide dismutase and glutathione peroxidase activities, compared to CCl4-treated mice (p < 0.05). This finding demonstrates that the polyphenolic extract from apple, particularly its peel, can be explored as a chemopreventive or chemotherapeutic agent against oxidative-stress-related liver disorders.