增加n-6脂肪酸对高脂诱导的大鼠胰岛素抵抗和血清游离脂肪酸谱的影响

Effect of the augment of n-6 fatty acids in dietary on insulin resistance and serum free fatty acid elements in the insulin resistance rats induced by high fat-fed

目的:探讨喂养饱和占总热量59%和n-6脂肪酸代替其中20%热量后,对胰岛素抵抗和血清游离脂肪酸谱的影响.方法:45只雄性Wistar大鼠分为3组.对照组喂饲普通饲料, 高脂组喂饱和脂肪酸提供59%热卡的高脂饲料,n-6脂肪酸组喂饲饲料为高脂饲料中饱和脂肪酸提供热量的20%由豆油中的C18∶ 2代替.各组共喂饲11周后测定指标.结果:①高脂组大鼠从第4周开始体重明显升高 ,糖负荷后血糖、胰岛素抵抗指数、血清瘦素、血清胆固醇和甘油三酯含量均较正常对照组明显升高.高脂组大鼠血清游离脂肪酸谱中,饱和脂肪酸明显升高,不饱和脂肪酸明显下降.②n-6脂肪酸组从第1～10周体重均较高脂组明显减轻,糖负荷后血糖、血清胰岛素、胰岛素抵抗指数、血清胆固醇、甘油三酯和低密度脂蛋白含量均较高脂组明显降低;血清瘦素水平、高密度脂蛋白、18碳2烯酸较高脂组明显升高.结论:n-6脂肪酸代替诱导大鼠胰岛素抵抗的饱和脂肪酸的20%热量后可以降低胰岛素抵抗,同时血清中18碳2烯酸提高.

Objective:To investigate the effect of a high-fat diet inducing insulin resistance, or 20% of saturated fatty acid replaced by n-6 fatty acids, on insulin resistance and serum free fatty acid profile. Methods:45 male Wistar rats were divided into three group. The control rats were fed with common diet.The high fat-fed group were fed with high fat diet containing 59% saturated free fatty acids. The n-3 fatty acids group was fed with 20% of saturated fatty acid replaced by C18:2 in bean oil instead of high-fat diet.Theitems were detected at week11. Results:①Compared with the normal group, the body weight at week 4 and the glucose after oral glucose test, insulin resistance index, serum leptin, serum cholesterol and serum triglyceride were significantly decreased in high-fat fed group. The saturated fatty acid was significantly increased, unsaturated free fatty acids were significantly decreased in the high fat-fed group.②Compared with these of fat-fed group, the body weight, blood glucose levels after oral glucose insulin resistance index, serum cholesterol(CHO), triglyceride(TG) and lower density lipoprotein cholesterol (LDL-CH) were decreased. the fasting serum leptin ,high density lipoprotein cholesterol (HDL-CH) and C18:2 were significantly increased in N-6 PUFAs group. Conclusion:High fat feeding replaced by 20% of saturated fatty acid by n-6 fatty acids could markedly decrease insulin resistance, and the serum C18:2 were significantly increased in these rats.