高脂饮食对老年大鼠氧化应激及脂质代谢的影响

Effect of the High Fat Diet-induced on Oxidative Stress and Lipid Metabolism of Old Rats

为观察高脂饮食对老年大鼠氧化应激及其脂质代谢的影响,将60只20～22月龄(老年)Wistar大鼠随机分为老年对照组和老年高脂组;对照组给予普通饲料喂养,高脂组给予高脂饲料喂养。8w后测定大鼠血清空腹血糖(FPG)、胰岛素(FINS)、甘油三酯(TG)、总胆固醇(TC)、游离脂肪酸(FFA),血清及肝组织内超氧化物歧化酶(SOD)活力和丙二醛(MDA)、谷胱甘肽(GSM)含量,观察肝组织学改变。结果老年高脂组大鼠体质量、体脂和体脂含量与老年对照组相比差异有统计学意义(P<0.05);老年高脂组大鼠血清甘油三酯(TG)、总胆固醇(TC)、空腹血糖(FPG)、游离脂肪酸(FFA)、空腹胰岛素(FINS)明显高于老年对照组(P<0.01);老年高脂组大鼠血清SOD、GSM明显降低,而MDA显著增高,与对照组比较差异有统计学意义(P<0.05或P<0.01);肝组织匀浆中SOD、MDA、GSM与血清中的趋势相同;老年高脂组肝脏脂肪变性的严重程度明显高于对照组。说明高脂饮食状态下,可以造成大鼠胰岛素抵抗和血脂升高,并且机体存在氧化和抗氧化的失衡,这与高脂膳食诱导的糖脂代谢紊乱有关。

To investigate effect of the high fat diet-induced on oxidative stress and lipid metabolism of old rats, 60 male wistar rats （20 - 22 months aged） were randomly divided into 2 groups ： Group NC received standard laboratory chow diet. Group HF were fed with high fat diet. After 8 weeks, detecting the biochemical index of rats serum fasting blood-glucose （FPG）, fasting insulin （FINS）, triglyceride （TG）, total cholesterol （TC）, free fatty acid （FFA） and the contents of superoxide dismutase （ SOD）, 3,4-Methylenedioxy methamphetamine （MDA） and glutathione （GSM） both in rats serum and liver tissue ; Observing the change of liver tissue. It is resulted that after highfat feeding for 8 weeks, rats from group high fat diet had higher body mass, body fat and content of body fat than the old control group （ P 〈 0.05 ） ; The serum TG, TC, FPG, FFA and FINS of the old high fat diet group were significantly increased than the old control group（P 〈 0.01 ）. The contents of serum and liver tissue SOD, GSM from the old high fat diet group decreased greatly, but the contents of MDA increased significantly. There were significant difference between two groups in the biochemical index of oxidative stress（P 〈0.05 or P 〈0.01 ） ; There were significant difference between two groups in the severe degree of liver fat deterioration. It is conclused that the high fat diet can induce hyperlipemia and insulin-resist and cause unbalance of oxidation and oxidation-resist, which is related to the carbohydrate and lipid metabolism disorder in rats.