Glycyrrhizin protects mice from concanavalin A-induced hepatitis without affecting cytokine expression

The administration of concanavalin A (Con A) to mice induces cytokine-dependent hepatitis. In the present study, the effect of glycyrrhizin on Con A-induced hepatitis was examined. Treatment of mice with Con A (0.2 mg/mouse, i.v.) induced elevation of the plasma transaminase activities at 24 h. Mice were treated with glycyrrhizin (100, 200 and 400 mg/kg, i.p.), and glycyrrhizin at the doses of 200 and 400 mg/kg inhibited the Con A-induced elevation of the plasma transaminase activities. At 1 h after Con A treatment, interferon-gamma, tumor necrosis factor-alpha, interleukin-2 and interleukin-6 proteins were released into the plasma. Although treatment with glycyrrhizin at 200 mg/kg inhibited Con A-induced hepatitis, it did not affect the release of any of these Con A-induced cytokines into the plasma. The present results clearly show that glycyrrhizin inhibited Con A-induced hepatitis without affecting cytokine expression.