Yang RuiLi, Le Guowei, Li Anlin, Zheng Jianliang, Shi Yonghui
Key Laboratory of Food Science and Security, Ministry of Education, Southern Yangtze University, Wuxi, Jiangsu, China.
Nutrition. 2006 Nov-Dec;22(11-12):1185-91. doi: 10.1016/j.nut.2006.08.018.
The present study explored the effect of antioxidant capacity on blood lipid metabolism and lipoprotein lipase (LPL) activity of rats fed with a high-fat diet (HFD). Furthermore, the relation of the atherosclerotic index (AI) and LPL activity to total antioxidant capacity (TAC) was studied.
Thirty-two Sprague-Dawley rats were randomly assigned to one of four groups (n = 8). The control group consumed an ordinary diet (5.1% fat, w/w). The other three experimental groups were fed with an HFD (14.1% fat, w/w), an HFD plus 0.1% lipoic acid (LA), or an HFD plus 0.1% N-acetylcysteine (NAC). After 4 wk, serum levels of triacylglycerol, total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol and LPL activity were examined. To evaluate rats' antioxidant status, TAC and superoxide dismutase activities and malondialdehyde level were measured.
The HFD induced abnormal increases in lipid peroxidation, serum concentrations of total cholesterol, triacylglycerol, and low-density lipoprotein cholesterol, and a decrease in high-density lipoprotein cholesterol concentration. Decreased activity of LPL, accompanied by a depressed antioxidant defense system, was observed in HFD-fed rats. These changes were partially restored in the NAC- and LA-treated groups. There was a negative correlation between AI and TAC (r = -0.969, P < 0.05). In addition, a significant positive correlation between LPL activity and TAC was found (r = 0.979, P < 0.05).
Oxidative injury and lipid abnormalities were induced by an HFD. Administration of LA and NAC can improve the antioxidant capacity and activity of LPL and reduce blood lipid significantly. Antioxidant capacity is correlated with AI and LPL activity.
本研究探讨抗氧化能力对高脂饮食（HFD）喂养大鼠血脂代谢及脂蛋白脂肪酶（LPL）活性的影响。此外，还研究了动脉粥样硬化指数（AI）和LPL活性与总抗氧化能力（TAC）的关系。
将32只Sprague-Dawley大鼠随机分为四组（n = 8）。对照组给予普通饮食（脂肪含量5.1%，w/w）。其他三个实验组分别给予HFD（脂肪含量14.1%，w/w）、HFD加0.1%硫辛酸（LA）或HFD加0.1%N-乙酰半胱氨酸（NAC）。4周后，检测血清甘油三酯、总胆固醇、低密度脂蛋白胆固醇和高密度脂蛋白胆固醇水平以及LPL活性。为评估大鼠的抗氧化状态，测定TAC、超氧化物歧化酶活性和丙二醛水平。
HFD导致脂质过氧化异常增加，血清总胆固醇、甘油三酯和低密度脂蛋白胆固醇浓度升高，高密度脂蛋白胆固醇浓度降低。在HFD喂养的大鼠中观察到LPL活性降低，同时抗氧化防御系统受到抑制。在NAC和LA处理组中，这些变化部分得到恢复。AI与TAC之间存在负相关（r = -0.969，P < 0.05）。此外，发现LPL活性与TAC之间存在显著正相关（r = 0.979，P < 0.05）。
HFD诱导氧化损伤和脂质异常。给予LA和NAC可提高抗氧化能力和LPL活性，并显著降低血脂。抗氧化能力与AI和LPL活性相关。
