Huang C J, Fwu M L
Department of Agricultural Chemistry, National Taiwan University, Taipei, Republic of China.
J Nutr. 1992 May;122(5):1182-9. doi: 10.1093/jn/122.5.1182.
To investigate the effects of dietary protein and polyunsaturated fat levels on tissue lipid peroxidation and antioxidative enzymes, Long-Evans male weanling rats were fed either an 8% lactalbumin diet containing 2% (L2), 5% (L5), 10% (L10), 15% (L15) or 20% (L20) soybean oil or a 20% lactalbumin diet containing 5% (N5) or 20% (N20) soybean oil for 8 weeks. The tissue thiobarbituric acid-reactive substances (TBARS) concentrations of the L2 group were similar to those of the N5 group except in plasma in which they were higher. The L5 group generally showed tissue TBARS concentrations comparable to the N20 group. Gradually increasing the dietary soybean oil level in the low protein diet further increased the tissue TBARS concentrations. The L20 group had significantly higher TBARS in RBC, liver, heart, kidney and muscle than the N20 group. The low protein-fed groups had lower activities of glutathione peroxidase (EC 1.11.1.9), superoxide dismutase (EC 1.15.1.1) and glucose-6-phosphate dehydrogenase (EC 1.1.1.49) in liver and catalase (EC 1.11.1.6) in RBC than the N5 group. Compared with the N5 group, the N20 group also showed higher TBARS concentrations and lower activities of certain antioxidative enzymes in some tissues. The antioxidative enzyme activities decreased more drastically with the increasing dietary soybean oil level in the low protein-fed groups than in those fed a normal level of protein. Supplementation of 150 mg/kg of all-rac-alpha-tocopheryl acetate to the L15 diet slightly decreased the TBARS in plasma, heart and liver and restored the depressed activities of RBC superoxide dismutase and catalase. The results indicated that insufficiency of dietary protein aggravates the enhanced production of TBARS and the reduced activities of antioxidant enzyme in rats fed a high soybean oil diet.
为研究膳食蛋白质和多不饱和脂肪水平对组织脂质过氧化及抗氧化酶的影响，将雄性长 Evans 断奶大鼠分为两组，分别给予含 2%（L2）、5%（L5）、10%（L10）、15%（L15）或 20%（L20）大豆油的 8%乳白蛋白日粮，或含 5%（N5）或 20%（N20）大豆油的 20%乳白蛋白日粮，喂养 8 周。除血浆中 L2 组的硫代巴比妥酸反应性物质（TBARS）浓度高于 N5 组外，L2 组的组织 TBARS 浓度与 N5 组相似。L5 组的组织 TBARS 浓度总体上与 N20 组相当。在低蛋白日粮中逐渐提高膳食大豆油水平会进一步增加组织 TBARS 浓度。L20 组红细胞、肝脏、心脏、肾脏和肌肉中的 TBARS 显著高于 N20 组。与 N5 组相比，低蛋白喂养组肝脏中的谷胱甘肽过氧化物酶（EC 1.11.1.9）、超氧化物歧化酶（EC 1.15.1.1）和葡萄糖-6-磷酸脱氢酶（EC 1.1.1.49）以及红细胞中的过氧化氢酶（EC 1.11.1.6）活性较低。与 N5 组相比，N20 组在某些组织中也表现出较高的 TBARS 浓度和较低的某些抗氧化酶活性。低蛋白喂养组中，随着膳食大豆油水平的增加，抗氧化酶活性的下降幅度比正常蛋白喂养组更大。在 L15 日粮中添加 150 mg/kg 的消旋α-生育酚醋酸酯可使血浆、心脏和肝脏中的 TBARS 略有降低，并恢复红细胞超氧化物歧化酶和过氧化氢酶的降低活性。结果表明，膳食蛋白质不足会加重高大豆油日粮喂养大鼠中 TBARS 生成的增加和抗氧化酶活性的降低。
