内质网应激、miR-375在高糖高脂介导胰岛β细胞凋亡中的作用

Roles of endoplasmic reticulum stress and miR-375 in apoptosis of pancreatic β cells induced by hyperglycemia and hyperlipidemia

目的观察不同糖脂浓度时内质网应激及miR-375表达的改变对大鼠胰岛RINm5F细胞增殖、凋亡的影响。方法RINm5F细胞分别培养在含不同糖脂浓度的培养液中,利用CCK-8法检测细胞的增殖活性,实时荧光定量PCR(qt-PCR)检测内质网应激相关基因XBP-1,CHOP以及miR-375的表达,Western blot检测凋亡基因caspase-3以及CHOP蛋白的表达。结果相同葡萄糖浓度时,随着棕榈酸浓度的增加,内质网应激相关基因XBP-1 mRNA、CHOP mRNA以及miR-375的表达水平增高(P<0.05),胰岛β细胞的增殖活性下降(P<0.05),Western blot检测可见CHOP及caspase-3蛋白表达均增加。结论在高糖高脂的作用下,内质网应激的诱导及miR-375的增加与胰岛β细胞的凋亡相关。

Objective To investigate the roles of endoplasmic reticulum stress and miR - 375 in the apoptosis and multiplica- tion of RINm5F cells under different concentrations of glucose and fat. Methods RINmSF cells were cultured in vitro under different concentrations of glucose and palmitate acid, The Cell Counting Kit -8 was used to measure the proliferative activity of cells. Quantitative real - time PCR（ qt - PCR） was performed to measure endoplasmic reticulum stress related genes XBP - 1, CHOP and miR - 375 expression, and Western blot was used to measure the expression levels of CHOP protein and caspase - 3 protein. Results Under the condition of the same concentration of glucose, plamitate acid could promote the expression of XBP - 1 mRNA, CHOP, mRNA, miR - 375 （ P 〈 0, 05 ）, and decrease the proliferation activity of pancreatic islet beta cells （ P 〈 0. 05 ） ; Western blot detection showed that CHOP and caspase - 3 protein expression were increased. Conclusion Under the action of hyperglycemia and hyperlipidemia, the induction of endoplasmie retieulum stress and the increase of miR - 375 are related to the apoptosis of pancreatic β cells.