高脂饮食对小鼠脂质代谢和leptin基因表达水平的影响

Effect of High Fat Diet on Lipid Metabolism and Expression of Leptin Gene in Mice

目的建立高脂饮食诱导小鼠肥胖模型,分析高脂饲料对小鼠脂质代谢和leptin基因表达水平的影响。方法用高脂饲料饲喂小鼠,每周定时称重和断尾采血一次,分别测定血清中血糖、胆固醇、甘油三酯、胰岛素和leptin的浓度;5周后,分离、称重小鼠体脂并提取腹部脂肪组织RNA,半定量RT-PCR分析leptin基因表达水平。结果从第2周开始,实验组小鼠体重明显高于对照组小鼠,4周后,体重差异显著(P<0.05);血清中血糖、胆固醇、甘油三酯、胰岛素和leptin的含量随体重增加明显增高,4周后,差异显著(P<0.05);实验组体脂含量明显高于对照组(P<0.05),半定量RT-PCR分析表明,肥胖小鼠脂肪组织leptin基因表达水平高于对照组(P<0.05)。结论高脂饮食诱导可建立小鼠肥胖模型,并能够引起高胰岛素和高leptin血症,为进一步研究肥胖的发病机制奠定基础。

Objective To establish a mouse model of obesity and analyze the effect of high fat diet on lipid metabolism and expression of leptin gene. Methods 20 Kunming mice were randomly divided into control and experimental groups, 10 per each group. The experimental groups were fed with high fat diet. The body weight was recorded and the blood sample was taken weekly. After five weeks, the body fat was separated and weighed. Serum cholesterol （CHO）, glucose （GLU）, triglyeride （TG）, insulin and leptin were measured and the data were compared between the two groups. RNA was extracted from abdomen adipose tissue and semi-quantitative RT-PCR was conducted to analyze the expression level of leptin gene. Results From the second week, the body weight of the experimental groups increased obviously. Four weeks later, the difference was significant （ P 〈 0.05）. The concentrations of serum CHO, GLU, TG, insulin and leptin in the experimental groups were higher than that of the control group. The body fat displayed significant difference between the two groups （P 〈 0.05）. Semi-quantitative RT-PCR demonstrated the expression level of leptin gene in fat mice was higher than that of control group. Conclusion High fat diet can be used to establish a mouse model of obesity and result in hyperinsulinism and high leptin in the serum.