阿司匹林和TNF-α对3T3-L1脂肪细胞糖代谢和胰岛素敏感性的影响及其机制

Effects of aspirin and tumor necrosis factor-α on glucose metabolism and insulin sensitivity in 3T3-L1 adipocytes

目的 观察阿司匹林和肿瘤坏死因子α(TNF α)对脂肪细胞糖代谢和胰岛素敏感性的影响。方法 检测阿司匹林和TNF α处理 3T3 L1脂肪细胞对培液中葡萄糖消耗量的影响 ,以 2 脱氧 3 H D 葡萄糖摄入法观察葡萄糖的转运率 ,用半定量RT PCR观察胰岛素信号系统转导相关基因的表达。结果葡萄糖消耗实验发现 ,5mmol/L阿司匹林和 5 μg/LTNF α作用 48h使 3T3 L1脂肪细胞葡萄糖的消耗分别增加 2 5 %和 46% ,在 10 0nmol/L胰岛素存在条件下 ,阿司匹林轻度增加葡萄糖消耗 ( 10 % ) ,而TNF α却显著减低葡萄糖的消耗 ,同时用阿司匹林和TNF α处理 ,脂肪细胞的葡萄糖消耗较单独TNF α处理明显增加 ;葡萄糖转运实验发现 ,5mmol/L的阿司匹林作用 72h增加 3T3 L1脂肪细胞基础和胰岛素刺激的葡萄糖转运 (P <0 .0 1) ,5 μg/L的TNF α作用 72h增加基础葡萄糖转运 (P <0 .0 5 ) ,但抑制胰岛素刺激的葡萄糖转运 ,同时加入阿司匹林后 ,减低TNF α对胰岛素刺激的葡萄糖转运的抑制 (P <0 .0 5或P <0 .0 1)。半定量RT PCR发现 ,TNF α抑制葡萄糖转运体 4(GLUT4)和c cbl相关蛋白 (CAP)基因的表达 ,而阿司匹林并不影响GLUT4和CAP的表达 ,但是能减低TNF α对GLUT4和CAP表达的抑制作用。结论 在 3T3 L1脂肪细胞 。

Objective To observe the effects of aspirin and tumor necrosis factor-α (TNF-α) on glucose metabolism and insulin sensitivity in 3T3-L1 adipocytes. Methods The amount of glucose disappearance from the culture medium after incubation with aspirin and TNF-α for 48 h was determined as glucose consumption of the cells. Theuptakeof2-deoxy-〔 3H〕-D-glucosewasusedtoobserveglucosetransport. The mRNA levels of genes related signal transduction of insulin were evaluated by semi-quantitative RT-PCR. Results Glucose con-sumption test revealed that 5 mmol/L aspirin and 5 μg/L TNF-α significantly increased glucose consumption in 3T3-L1 adipocytes by 25% and 46% respectively. In the presence of 100 nmol/L insulin, aspirin increased glucose consumption by 10%, while TNF-α decreased glucose consumption; but the combination of TNF-α and aspirin potentiated glucose consumption. Glucose transport testrevealedthat3T3-L1adipocytestreated with 5 μg/L TNF-α for 72 h exhibited a significant decrease in insulin-sensitive glucose uptake (P<0.01) , but TNF-α increased basal glucose transport (P<0.05). In the presence of TNF-α, aspirin potentiated insulin-sensitive glucose uptake by 85% (P<0.01). Aspirin also significantly increased basal glucose transport and insulin-stimulated glucose transport (P<0.01 or P<0.05). Using semiquantitative RT-PCR techniques, it was found that TNF-α inhibited glucose transporter 4 (GLUT4) and c-cbl-associated protein (CAP) gene expression. Aspirin did not influence GLUT4 and CAP gene expression, but alleviated the inhibiting effect of TNF-α on GLUT4 and CAP expression. Conclusion Aspirin increases insulin sensitivity and partly antagonises TNF-α-induced insulin resistance in 3T3-L1 adipocytes.