Five cysteine-containing compounds have antioxidative activity in Balb/cA mice

Balb/cA mice were used to study the in vivo effect of N-acetyl cysteine, S-allyl cysteine, S-ethyl cysteine, S-methyl cysteine and S-propyl cysteine, all derived from garlic, on glutathione (GSH) concentration and catalase and glutathione peroxidase (GPX) activities in plasma, kidney and liver. Cysteine was used for comparison. The effects of these compounds on the levels of fibronectin, triglyceride (TG), cholesterol and alpha-tocopherol were also evaluated. Cysteine or cysteine-containing compounds were added to drinking water at 1 g/L. After 4 wk of treatment, GSH levels in kidney and liver were greater (P < 0.05) than in controls. Cysteine decreased catalase and GPX activities in liver, and enhanced both Fe2+ - and glucose-induced lipid oxidation in plasma, kidney and liver compared with the control group (P < 0.05). However, the administration of the five cysteine-containing compounds enhanced catalase and GPX activities in kidney and liver, and reduced Fe2+ - and glucose-induced lipid oxidation in plasma, kidney and liver compared with the control and cysteine-treated groups (P < 0.05). Intake of the five cysteine-containing compounds reduced fibronectin, TG and cholesterol concentrations in plasma and liver, and increased the alpha-tocopherol concentration in plasma, kidney and liver compared with the control and cysteine-treated groups (P < 0.05). The five cysteine-containing compounds derived from garlic had marked effects on antioxidant enzymes and spared alpha-tocopherol in mice. Furthermore, these compounds reduced fibronectin, TG and cholesterol concentrations in plasma. These data indicate that these compounds have a range of protective effects for cardiovascular disease prevention or therapy.