Protective action of fenugreek (Trigonella foenum graecum) seed polyphenols against alcohol-induced protein and lipid damage in rat liver

The study investigates the effect of fenugreek seed polyphenol extract (FPEt) on ethanol-induced damage in rat liver. Chronic ethanol administration (6 g kg(-1) day(-1) x 60 days) caused liver damage that was manifested by excessive formation of thiobarbituric-acid-reactive substances, lipid hydroperoxides, and conjugated dienes, the end products of lipid peroxidation, and significant elevation of protein carbonyl groups and diminution of sulfhydryl groups, a marker of protein oxidation. Decreased activities of enzymic and non-enzymic antioxidant levels and decreased levels of thiol groups (both non-protein and protein) were observed in ethanol-treated rats. Further, ethanol significantly increased the accumulation of 4-hydroxynonenal protein adducts, nitrated and oxidized proteins in liver which was evidenced by immunohistochemistry. Administration of FPEt to ethanol-fed rats (200 mg kg(-1) day(-1)) significantly reduced the levels of lipid peroxidation products and protein carbonyl content, increased the activities of antioxidant enzymes, and restored the levels of thiol groups. The effects of FPEt were comparable with those of a positive control, silymarin. These findings show that FPEt ameliorates the pathological liver changes induced by chronic ethanol feeding.