Antiatherogenic and antiperoxidative effects of garlic and soy proteins in alcohol fed rats.

Rats fed with alcohol (18%) at 3.76 g/day for 45 days showed significant reduction in body weight, glutathione (GSH) content and activities of superoxide dismutase (SOD) and catalase in liver. Lecithin cholesterol acyltransferase (LCAT) in plasma, levels of HDL cholesterol in serum, hepatic bile acid production and fecal excretion of neutral sterols also showed significant reduction. Simultaneous feeding of garlic protein (GP) or soy protein (SP) (500 mg/kg body weight/day for 45 days) to alcohol fed groups increased each of above parameters significantly towards normal values. Increase in GSH content and catalase activity in liver, was significantly higher for SP treated group than for GP treated group. However, increase in plasma LCAT was significantly higher for GP treated group than for SP treated group. Alcohol fed rats showed significant increase in liver weight, serum and tissue cholesterol, serum triacylglycerol (TAG), phospholipids (PL) and free fatty acid (FFA) levels and activity of HMGCoA reductase in liver and intestine. Lipid peroxidation, glucose-6 phosphate dehydrogenase (G6PD), glutathione peroxidase (GPx) and glutathione reductase (GR) in liver and incorporation of labeled acetate into liver cholesterol also showed significant increase. GP and SP treated rats showed decrease in these values towards normal. GP feeding showed a better effect than SP in lowering serum and heart total cholesterol, and in maintaining GPx at near normal level, while SP feeding showed a better effect in lowering serum FFA level and maintaining GR activity at near normal level. In suppressing incorporation of labeled acetate into serum cholesterol, GP feeding showed a better effect than SP. Antiatherogenic and antiperoxidative effects of these proteins may be due to lower lysine/arginine ratio.