运动对老年肥胖大鼠脂联素的影响

Effect of exercise on adiponectin in aged obese rats

目的:探讨运动对老年肥胖大鼠内脏脂肪组织脂联素mRNA和蛋白质表达、血浆脂联素浓度及胰岛素抵抗的影响。方法:取雄性SD大鼠,鼠龄21 d,分青春期、壮年期和老年期三个阶段喂养高脂饲料(脂肪率为36.3%～40.0%),建立老年肥胖模型。鼠龄达到60周后,取自然生长老年大鼠随机分为对照组(C)和老年运动组(AE),n=6;取老年肥胖大鼠随机分为肥胖对照组(OC)和肥胖运动组(OE),n=6。动物跑台坡度0°,运动速度及时间为(15 m/min×15 min),4组/次,组间休息5 min,每次共运动60 min,5次/周,持续运动8周。8周后,检测内脏脂肪组织脂联素mRNA和蛋白质表达,测定血糖、血浆脂联素浓度和胰岛素浓度,计算胰岛素抵抗。结果:运动干预后,与对照组比较,肥胖对照组大鼠脂联素mRNA和蛋白质表达显著减低,血糖浓度和胰岛素抵抗明显增高;而老年运动组大鼠脂联素mRNA和蛋白质表达显著增高。与肥胖对照组大鼠比较,肥胖运动组大鼠脂联素mRNA和蛋白质表达显著增高、血浆脂联素水平增高,血糖浓度和胰岛素抵抗明显减低。结论:老年肥胖大鼠内脏脂肪组织脂联素mRNA和蛋白质表达均降低,伴随胰岛素抵抗、血糖升高。运动能显著增加其内脏脂肪组织脂联素mRNA和蛋白质表达,升高血浆脂联素水平,改善胰岛素抵抗,降低血糖。

Objective： To explore effects of exercise on the expression of adiponectin m RNA and protein in visceral adipose tissue,plasma adiponectin concentration,and insulin resistance of aged obese rats. Methods： Male SD rats age to 21 days old were fed with high-fat diet（ fat percentage was 36.3% to 40.0%） for three stages of adolescence,maturity and old age to establish elderly obesity rats model. When the rats aged to 60 weeks old,natural growing elderly rats were randomly divided into control group（ C） and aged exercise group（ AE）,n = 6; elderly obesity rats were randomly divided into obesity control group（ OC） and obesity exercise group（ OE）,n= 6. The treadmill grade was 0°,the exercise speed and time were 15 m/min×15 min,4 groups each time,between consecutive groups the rats had 5 minutes rest,the rats were exercised for 60 minutes every day,five days a week,continuous exercise for 8 weeks. Then,the expressions of adiponectin m RNA and protein in visceral adipose tissue were determined. The concentrations of blood glucose,plasma adiponectin and insulin were measured. Insulin resistance was calculated. Results： Comparison with control group,the expressions of adiponectin m RNA and protein were obviously decreased,the concentration of blood glucose and insulin resistance were significantly increased in obesity control group,while the expressions of adiponectin m RNA and protein were obviously increased. Comparison with obesity control group,the expressions of adiponectin m RNA and protein,the concentration of plasma adiponectin were obviously increased,the concentration of blood glucose and insulin resistance were significantly decreased in obesity exercise group. Conclusion： Adiponectin m RNA and protein expression in visceral adipose tissue is decreased and accompanied by high blood glucose and insulin resistance in elderly obesity rats. Exercise can increase the adiponectin m RNA and protein expression in visceral adipose tissue,elevate levels of plasma adiponectin,and decrease the level of blood glucose and insulin resistance in elderly obesity rats.