Rubus sanctus protects against carbon tetrachloride-induced toxicity in rat isolated hepatocytes: isolation and characterization of its galloylated flavonoids.

OBJECTIVES: Rubus sanctus Schreb., known from the Bible as 'holy thorn bush', grows wild in Egypt. Rubus sanctus aqueous alcoholic extract (RE) contains a complicated phenolic mixture (ellagitanins, flavonoids and caffeic acid derivatives). In this study, the phytochemical investigation of the plant was re-evaluated. Herein, we report on the isolation and identification of three galloylated flavonoids, namely kaempferol-3-O-(6''-O-galloyl)-(4)C(1)-beta-d-galactopyranoside, quercetin-3-O-(6''-O-galloyl)-(4)C(1)-beta-d-galactopyranoside and myricetin-3-O-(6''-O-galloyl)-(4)C(1)-beta-d-galactopyranoside for the first time from the Rubus genus. We further aimed at evaluating the potential protective effects of RE against carbon tetrachloride (CCl(4))-induced toxicity in isolated rat hepatocytes.

METHODS: Based on an initial concentration-response experiment, a concentration of 100 mug/ml was selected to investigate the hepatoprotective activity of RE.

KEY FINDINGS: Pretreatment with RE afforded protection as indicated by counteracting CCl(4)-induced cell death, and reduced glutathione depletion. In addition, RE ameliorated CCl(4)-induced enzyme leakage by 40% for lactate dehydrogenase, 30% for alanine aminotransferase and 20% for aspartate aminotransferase as compared with CCl(4)-treated cells. Moreover, RE counteracted CCl(4)-induced lipid peroxidation and inhibited spontaneous lipid peroxidation in the control group.

CONCLUSIONS: In conclusion, RE protects against CCl(4)-induced toxicity in isolated rat hepatocytes.