运动对胰岛素抵抗大鼠TNF-α和脂联素表达的影响

目的 探讨运动干预对高脂高糖饮食诱导的胰岛素抵抗大鼠循环及组织中肿瘤坏死因子（tumor necrosis factor-alpha,TNF-α）和脂联素表达的影响.方法 29只雄性S-D大鼠随机分为对照组9只和造模组20只,分别给予基础饲料与高脂高糖饲料喂养,6周后将造模成功的18只大鼠再随机分为模型组9只和运动组9只,运动干预6周后,测定血清TNF-α（放免法）和脂联素（酶联免疫吸附法）及肝脏和骨骼肌中TNF-α和脂联素mRNA表达（RT-PCR法）.结果 与对照组比较,模型组空腹血糖和胰岛素升高（5.06±0.38 vs 7.49±1.13,13.61±2.94 vs 33.57±4.87,P均〈0.05）,胰岛素敏感指数降低（-4.21±0.22 vs -5.51±0.16,P〈0.05）,血清TNF-α升高（2.39±0.44 vs 3.03±0.50,P〈0.05）,血清脂联素降低（0.86±0.08 vs 0.77±0.09,P〈0.05）;肝脏和骨骼肌中TNF-α mRNA均表达增强,脂联素mRNA表达明显减弱.与模型组比较,运动组空腹血糖及胰岛素明显降低（5.77±1.17 vs 7.49±1. 13,25.69±4.27 vs 33.57±4.87,P均〈0.05）,胰岛素敏感指数上升（-5.10±0.31 vs -5.51±0.16,P〈0.05）,血清TNF-α降低（2.40±0.59 vs 3.03±0.50,P〈0.05）,脂联素升高（0.86±0.10 vs 0.77±0.09,P〈0.05）;肝脏和骨骼肌中TNF-α mRNA均表达减弱,脂联素mRNA表达增强.结论 运动干预明显改善胰岛素抵抗,其机制可能与调节TNF-α和脂联素的表达有关.

Effect of exercise training on tumor necrosis factor-alpha and adiponectin expressions in insulin resistance rats

Objective To investigate the effects of exercise training intervention on the expressions of TNF-α and adiponectin in circulation and tissues of high-fat/high-sucrose diet-induced insulin resistance rats. Methods 29 S-D rats were random divided into 2 groups: Control group (9 rats) and high-fat/high-sucrose diet group (20 rats). After fed for 6 weeks, 18 rats with insulin resistance were random divided into 2 groups: model group ( n = 9) and exercise group ( n = 9). After 6 weeks intervention, serum TNF-α and adiponectin concentration were measured by radioimmunity assay and ELISA respectively, while TNF-α and adiponectin mRNA expressions in liver and skeletal muscle were measured by RT-PCR. Results Fasting plasma glucose(FPG) and fasting serum insulin(FINS) levels increased significantly and insulin sensitivity index(ISI) decreased significantly in rats of model group than those in control group(7.49 ± 1.13 vs 5.06±0.38, 33.57 ±4.87 vs 13.61±2.94, -5.51±0.16 vs -4.21 ±0.22, all P <0.05). Serum TNF-α concentration was significantly higher than those in control group, while serum adiponectin concentration was significantly lower. (3.03 ± 0. 50 vs 2. 39 ± 0. 44, 0. 77 ± 0. 09 vs 0. 86 ± 0. 08, all P < 0. 05 ).Expressions of TNF-α mRNA in liver and skeletal muscle increased significantly and adiponectin mRNA expression significantly decreased in rats of model group compared to those in control group (0. 66 ± 0. 19 vs 0. 05 ± 0. 03, 1.15 ± 0. 20 vs 0. 25 ± 0. 10, 0. 25 ± 0. 10 vs 0. 85 ± 0. 13, all P < 0. 01 ). Fasting plasma glucose(FPG) and fasting serum insulin(FINS) levels decreased significantly and insulin sensitivity index (ISI) increased significantly in rats of exercise group than those in model group(5.77 ± 1.17 vs 7.49 ±1.13, 25.69 ±4.27 vs 33.57 ±4. 87, -5. 10 ±0.31 vs -5.51 ±0. 16, all P <0.05) ;Serum TNF-α concentration was significantly lower and serum adiponectin concentration was significantly higher in rats of exercise group than those in model group ( 2.40 ± 0. 59 vs 3.03 ± 0. 50, 0. 86 ± 0. 10 vs 0. 77 ± 0. 09, all P < 0. 05); Expressions of TNF-α mRNA in liver and skeletal muscle decreased significantly and adiponectin mRNA expression increased significantly in rats of exercise group compared to those in model group (0. 21±0. 10 vs 0.66±0. 19, 0.49 ±0. 17 vs 1.15 ±0.20, 0.97 ±0.20 vs 0. 25 ±0. 10, all P <0.01). Conclusion Exercise training can significantly improve insulin resistance, which may be through modulating the expressions of TNF-α and adiponectin.