Physiological Responses to a Natural Antioxidant Flavonoid Mixture, Silymarin, in BALB/c Mice: I Induction of Transforming Growth Factor β1 and c-myc in Liver with Marginal Effects on Other Genes

Abstract

Silymarin, a mixture of flavonolignans isolated from Silybum marianum, is known for its hepatoprotective properties. We investigated the expression of cytokines in mouse liver following treatment with 0, 10, 50, and 250 mg/kg of silymarin once daily for 5 days. A dose-related but insignificant decrease of circulating alanine aminotransferase and aspartate aminotransferase after silymarin treatment was observed, suggesting that silymarin treatment did not induce hepatic damage. Silymarin treatment caused significant increases in the expressions of transforming growth factor (TGF) β1 and c-myc in liver. No significant difference was detected among these treatments in the expression of hepatocyte growth factor, interferon γ, tumor necrosis factor α, and class II major histocompatibility complex. These results suggest that alterations of TGFβ1 and c-myc expression in the liver may be involved in the hepatoprotective effects of silymarin observed in other studies.

Key words

Silymarin - TGFβ - c-myc - flavonoid - liver - Silybum marianum - Asteraceae

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