胰升血糖素样肽1对3T3-L1前脂肪细胞增殖及分化的影响

目的探讨胰升血糖素样肽1（GLP-1）对3T3-L1前脂肪细胞增殖及分化的影响。方法在3T3-L1前脂肪细胞增殖和分化的不同阶段添加不同浓度梯度的GLP-1（7—36），使用XTT比色法测定细胞增殖情况，油红O脂肪染色、异丙醇萃取法评价细胞分化情况，RT-PCR法测定不同分化阶段PPAR-ymRNA表达水平。结果高浓度GLP-1（10^-9～10^-7mool／L）能够减弱3T3-L1前脂肪细胞的增殖能力；GLP-1在10^-11～10^-8mmoL／浓度梯度均存在抑制3T3-L1前脂肪细胞向脂肪细胞分化的作用，但对分化过程中PPARymRNA的表达水平均未见显著影响。结论本研究发现GLP-1能够抑制3T3-L1前脂肪细胞增殖及分化，提示脂肪细胞可能也是GLP-1减轻体重作用的潜在靶点。

Effect of GLP-1 on proliferation and differentiation of 3T3-L1 preadipocytes

Objective To investigate the effects of glucagon-like peptide-1 （GLP-1）on the proliferation and differentiation of 3T3-L1 preadipocytes. Methods 3T3-L1 preadipocytes were cocultured with graded doses of GLP-1. XTT and Oil Red O-staining were employed to evaluate the cell growth and the lipid accumulation respectively. The level of PPAR-7 mRNA expression during the course of differentiation was determined with RT-PCR. Results GLP-1 at high doses （10^-9-10^-7 retool/L） attenuated the proliferation of 3T3-L1 preadipocytes. Moreover, GLP-1 showed inhibitory effect on the differentiation of 3T3-L1 preadipocytes at varying graded doses （10^-11-10^-8 retool/L）, but exhibited no obvious effect on PPAR-7 mRNA expression during the course of differentiation. Conclusions GLP-1 inhibits the proliferation and differentiation of 3T3-L1 preadipocytes, suggesting that adipocytes might be a potential target of GLP-1 for weight loss.