Tissue thiol induction in mice and protective effect against pyrrolizidine alkaloids by dietary ethoxyquin and...

Dietary administration of ethoxyquin (EQ) and methionine hydroxy analog (MHA) induced the thiol concentrations in liver, kidney, small intestine and stomach of mice accompanied with hepatic hypertrophy. The hepatic thiol levels among EQ, EQ-MHA, or EQ-methionine treated mice were significantly higher (p less than 0.01) than that of the controls. Hepatic hypertrophy was apparent with 0.031% EQ-0.063% MHA in the diet. EQ feeding, as 0.5% w/w of feed with or without another additive, also resulted in reduced weight gain. The toxicity of pyrrolizidine alkaloids (PAs) was reduced by feeding diets containing 0.063% EQ-0.125% MHA or 0.125% EQ-0.25% MHA. The intraperitoneal LD50 values of PAs in these two EQ-MHA feeding groups were 92.8 and 94.0 mg/kg, respectively, compared to that of 71.3 mg/kg for the controls.