脐带间充质干细胞(UC-MSC)通过增强自噬缓解2型糖尿病小鼠肝脏胰岛素抵抗

Umbilical Cord—mesenchymal Stem Cells Attenuate Insulin Resistance through Increasing Autophagy in the Liver of Type 2 Diabetes

为了探讨人脐带间充质干细胞缓解胰岛素抵抗的作用及其增强自噬的分子机制.采用C57IBL小鼠高脂喂养后STZ注射造2型糖尿病模型.经尾静脉输注1×10^(6)个脐带间充质干细胞后每天检测小鼠血糖,通过HE染色和PAS染色检查肝脏中的脂质沉积和肝糖原含量.免疫印迹检测其肝脏LC3B、ATG7和Bclin1;免疫荧光检测LC3.结果显示UC-MSC输注后小鼠空腹血糖和胰岛素抵抗指数(HOMA-IR指数)显著下降.WB显示干细胞输注后小鼠肝脏中LC3和ATG7的表达明显增加,LC3 II/I的比例上升.因此,在2型糖尿病小鼠中,UC-MSC输注能有效降低血糖,改善胰岛素抵抗,同时增加小鼠肝脏中的自噬.

To observe the effect of human umbilical cord-mesenchymal stem cells(UC-MSC)relieve insulin resistance on type 2 diabetes.And to explore the possible mechanism of its regulating autophagy.We performed type 2 diabetic mice were induced by high-fat diet combined with a low dose of strepto-zotocin(STZ).After 1x10*UC-MSCs suspended in 200 pul.PBS were intravenously infused into the mice via the tail vein,the blood glucose levels were measured every day.The liver lipid deposition and the con-tent of hepatic glycogen were observed by HE and PAS staining.Its liver LC3B,ATG7 and Belinl were tested by westem blot.After MSCs infusion,blood glucose level and homeostasis model of assessment for insulin resistance index were significantly decreased(both P<0.01).Western blot suggested autophagy related proteins LC3 and Atg7 in the liver are both increasing.Moreover,the ratio of LC3 II/I(means intensity of autophagy)is significant increase.Our data confirmed that,in type2 diabetic mouse,UC-MSCs are able to effectively lower the blood glucose level,improve insulin sensitivity,and increase liver autophagy.