褪黑素改善胰岛素抵抗3T3-L1脂肪细胞葡萄糖的摄取

目的研究褪黑素对游离脂肪酸(FFA)诱导的胰岛素抵抗3T3-L1脂肪细胞葡萄糖摄取能力的影响。方法 "鸡尾酒"法培养诱导3T3-L1成纤维细胞分化成脂肪细胞,油红O染色鉴定脂肪细胞形态;利用棕榈酸(300μmol/L)诱导脂肪细胞的胰岛素抵抗,采用液体闪烁法检测细胞葡萄糖摄取能力;检测褪黑素对FFA处理的3T3-L1脂肪细胞的葡萄糖摄取能力的影响。结果 3T3-L1细胞经诱导分化成脂肪细胞,油红O染色呈圆形,脂滴呈典型的"戒环样"形态;用FFA处理上述细胞6 h后,细胞的葡萄糖摄取能力明显降低;褪黑素可以促进FFA处理的3T3-L1脂肪细胞胰岛素介导的葡萄糖摄取。结论 FFA可以降低胰岛素诱导的体外培养的脂肪细胞葡萄糖摄取能力,可能是胰岛素抵抗的病因之一。褪黑素可以干预FFA的作用,增加细胞的葡萄糖摄取能力。

Melatonin improving the glucose uptake of 3T3-L1 adipocytes incubated with free fatty acids

Purpose To investigate the effect of melatonin on the glucose uptake in insulin resistance 3T3-L1 preadipocytes induced by free fatty acids.Methods 3T3-L1 preadipocytes were incubated in adipogenic cocktail for 10 days and then adipocytes were obtained for study.Adipocytes of insulin resistance were induced by incubating with free fatty acids(FFA,palmitinic acid,300 μmol/L),and then melatonin was added.Glucose uptake was detected in adipocytes by luminescent counter.Results Adipocytes with typical lipid droplet were harvested after incubating in adipogenic cocktail for 10 days.FFA(300 μmol/L,6 h) decreased the glucose uptake in the adipocytes.However,the addition of melatonin into the FFA-treated adipocytes resulted in a increase of glucose uptake.Conclusion FFA inhibited the glucose uptake induced by insulin in the 3T3-L1 preadipocytes inducing insulin resistance,whereas melatonin attenuated the effect of FFA by promoting the glucose uptake of adipocytes.