葡萄糖-6-磷酸脱氢酶在高脂饲料诱导肥胖中的作用

Roles of glucose-6-phosphate dehydrogenase in obesity induced by high fat diet

目的探讨葡萄糖-6-磷酸脱氢酶(G6PD)及其下游NADPH氧化酶在高脂饲料诱导肥胖中的作用。方法 40只雄性Wistar大鼠随机分为高脂饲料组(30只)和基础饲料组(10只),6周后,高脂饲料组依据体重增加量筛选出位于上1/3和下1/3的大鼠为肥胖组和抵抗组(各10只),肥胖组和抵抗组大鼠继续喂饲高脂饲料,基础饲料组作为正常对照组,13周后处死,测定生化指标,检测脂肪组织中G6PD的活性,采用RT-PCR法检测G6PD、NOX亚基P22基因表达。结果肥胖组大鼠血糖明显高于对照组(P<0.05),甘油三酯、体脂含量显著高于抵抗组(P<0.05),胰岛素、胰岛素抵抗指数、体重都显著高于对照组和抵抗组(P<0.05),对照组和抵抗组之间差异无显著性,肥胖组G6PD的表达和活性均低于对照组和抵抗组(P<0.05),P22亚基在肥胖组表达水平显著高于对照组和抵抗组(P<0.05)。结论 G6PD及其下游的NADPH氧化酶可能在肥胖的发生和发展中起重要作用。

Objective To explore the roles of glucose-6-phosphate dehydrogenase（G6PD） and its downstream NADPH oxidase（NOX） in obesity induced by high fat diet.Methods 40 male Wistar rats were randomly divided into a high fat diet group（30 rats） and a control group（10 rats） fed with rat chow.After six weeks,rats fed with high fat diet were screened out obesity-prone group and obesity-resistant group based on the gain of body weight.obesity-prone group and obesity-resistant group rats continued to be fed with high fat diet.Basic diet group served as normal control.All rats were killed after 13 weeks.Biochemical markers and G6PD activity were determined in adipose tissues.The expression of G6PD and the NOX subunit of P22 gene were detected using RT-PCR.Results Blood glucose levels were higher in obesity-prone group rats than those in control rats（P0.05）.Triglyceride levels and body fat contents were significantly higher in OP rats than that in obesity-resistant group rats（P0.05）.Insulin,insulin resistant index,body weight were significantly higher in obesity-prone group rats than that in control and obesity-resistant group rats（P0.05）.There was no significant difference between the control and obesity-resistant group rats.The activity and expression of G6PD in the obesity-prone group rats were lower than those in the control and obesity-resistant group rats（P0.05）.The expression of P22 subunit in the obesity-prone group rats was significantly higher than that in the control and obesity-resistant group rats（P0.05）,but there was no significant difference between the control and OR rats.Conclusion G6PD and its downsream NAPDH oxidase may play an important role in the pathogenesis and development of obesity.