Myricitrin exhibits antioxidant, anti-inflammatory and antifibrotic activity in carbon tetrachloride-intoxicated mice

• Myricitrin decreased hepatic lipid peroxidation and increased GSH and CYP2E1 level.
• Myricitrin reduced COX-2 and TNF-α overexpression and inflammation in the liver.
• Myricitrin inhibited hepatic expression of TGF-β1 and α-SMA and liver fibrosis.
• Myricitrin increased PCNA expression in regenerating liver tissue.

Myricetin-3-O-α-rhamnoside (myricitrin) is a naturally occurring phenolic compound which possesses antioxidant and anti-inflammatory activity. The aim of this study was to determine the hepatoprotective effects of myricitrin. Myricitrin at doses of 10, 30 and 100 mg/kg and silymarin at dose of 100 mg/kg were administered to BALB/cN mice by oral gavage, once daily for two consecutive days following carbon tetrachloride (CCl4)-intoxication. Myricitrin significantly ameliorated CCl4-induced increase in serum aspartate transaminase (AST) and alanine transaminase (ALT) levels and histopathological changes in the liver. Hepatic oxidative stress was reduced by myricitrin, as evidenced by the decrease in lipid peroxidation, with concomitant increase in glutathione (GSH) level and cytochrome P450 2E1 (CYP2E1) expression. In addition, cyclooxygenase-2 (COX-2) and tumor necrosis factor-alpha (TNF-α) overexpression in the liver was reduced, suggesting the suppression of inflammation. The expression of transforming growth factor-beta1 (TGF-β1) and alpha-smooth muscle actin (α-SMA) was markedly ameliorated, indicating the inhibition of profibrotic response. Myricitrin also improved the regeneration of hepatic tissue after CCl4-intoxication, as evidenced by increased proliferating cell nuclear antigen (PCNA) expression. The results of the current study suggest that myricitrin exhibits a significant hepatoprotective activity. Myricitrin provided better hepatoprotection when compared to silymarin, which is consistent with its higher in vitro antioxidant potential.