大豆蛋白質對慢性腎衰竭患者血壓、血脂與腎功能的影響
Hyperlipidemic factors contribute to the high cardiovascular risk in hemodialysis patients and may accelerate the progression of renal disease. Soy protein has been shown to reduce some atherogenic lipid concentrations in subjects with normal renal fu nction, and slow progression of renal injury, reduce blood pressure in experimental animals and human subjects. The mechani sm and components of soy responsible have not been fully established. The objectives of this study were to 1) evaluate the eff ect of soy protein on serum lipid profiles and lipoprotein metabolism in hyperlipidemic and normolipidemic hemodialysis pati ents. 2) investigate the effect of the two fractions of soy protein hydrolysate on renal function, blood pressure and lipid metab olism in five-sixths nephrectomized rats, and to examine the active components of soy protein hydrolysate on ameliorating dis ease progression. Hyperlipidemic and normolipidemic hemodialysis patients were enrolled in a randomized, double-blind, pla cebo-controlled clinical trial. Thirty grams of isolated soy protein or milk protein was consumed daily as a beverage at breakfa st or postdialysis for 12 wk. Experimental animals were subjected to a nephrectomy and were fed two fractions isolated from s oy protein hydrolysate prepared by peptic hydrolysis for 13 wk. Results showed soy protein substitution significantly reduced total cholesterol, triglyceride, low-density lipoprotein cholesterol and apolipoprotein B concentrations, and the HDL-cholester ol was significantly increased in hyperlipidemic subjects. There were no significant changes in serum lipid and lipoprotein co ncentrations in normolipidemic subjects. Both soy protein hydrolysate fractions favorably affected chronic renal failure. The s upernatant fraction of soy protein hydrolysate had the most-significant decreases in blood pressure and significantly retarded p rogression of the experimentally induced renal disease. The precipitate fraction of soy protein hydrolysate exhibited significan tly increased fecal excretion of total cholesterol. In conclusion, our findings demonstrate that replacing a part of the daily prot ein with soy protein could be used in the nutritional management of moderately hyperlipidemic hemodialysis patients. The su pernatant fraction of soy protein hydrolysate had most-pronounced effect on slowing the progression of renal disease, and the precipitate fraction of soy protein hydrolysate had a protective effect on renal function resulting from lowering cholesterol.
Key words : soy protein, hemodialysis, hyperlipidemia, soy protein hydrolysate, renal failure, cholesterol, blood pressure
Effect of soy protein on blood pressure, lipid metabolism and renal function in chronic renal failure