目的 探讨褪黑素受体激动剂Neu-P11对胰岛素抵抗3T3-L1脂肪细胞IRS-1和GLUT-4表达的影响.方法 用高糖高胰岛素作用3T3-L1脂肪细胞24 h,建立胰岛素抵抗细胞模型.分别采用褪黑素、Neu-P11、褪黑素+luzin-dole(褪黑素受体拮抗剂)和Neu-P11+ luzindole处理细胞,并以未加药细胞作为对照.用葡萄糖氧化酶法检测培养液中的糖含量并计算糖消耗量,用蛋白质印迹分析检测细胞内IRS-1、GLUT-4蛋白表达变化.结果 胰岛素抵抗细胞用褪黑素和Neu-P11处理后,糖消耗量较未加药对照组升高(P＜0.05),GLUT-4、IRS-1的蛋白表达也增高(P＜0.05)；褪黑素和Neu-P11分别与luzindole联合作用于细胞后,细胞的上述蛋白表达较单用褪黑素组和单用Neu-P11组降低(P＜0.05),而与未加药对照组相比差异无统计学意义.结论 褪黑素受体激动剂Neu-P11可提高胰岛素抵抗脂肪细胞的胰岛素敏感性,增加糖消耗量,这种作用可能与上调IRS-1、GLUT-4蛋白的表达有关.

Objective: To investigate the influence of oral BCG on CD4+ CD25+ T regulatory cells in inducing immune tolerance.Methods: The EAE rats,induced by immunization with oral MBP,were randomly divided into BCG group(0.5mg/kg) and EAE group(PBS),with 15 rats per group,and 15 normal rats were used as control group.On 15d and 27d after treatment,CD4+ CD25+ T regulatory cells from peripheral blood,thymus and spleen were respectively determined by flow cytometry,and levels of serum IL-6,TGF-β,IgE and IgG were measured by ELISA.Results: Compared with EAE group,CD4+ CD25+ T regulatory cells from peripheral blood,thymus and spleen,and levels of IL-6 and TGF-β increased in BCG group after treatment,but serum IgE and IgG levels decreased.Conclusion: Oral BCG could induce immune tolerance by up-regulating the percentage of CD4+ CD25+ T regulatory cells,inhibiting effector T cell function.