抑制miR-375降低NIT-1胰岛β细胞脂性凋亡

Inhibition of miR-375 decreases lipoapoptosis in NIT-1 β cells

目的探讨抑制内源性微小RNA-375（miR-375）是否影响NIT-1胰岛β细胞的脂性凋亡。方法将NIT-1细胞分为4组：空白组（无脂质体）、空转组（脂质体）、阴性对照miRNA组（脂质体＋阴性对照miRNA）、2＇-O-me-375组（脂质体＋2＇-O-me-375，抑制内源性miR-375的作用）。转染72h后，各组细胞分别以500μmol／L棕榈酸孵育48h。以Hochest 33342染色和脱氧核糖核酸末端转移酶介导的缺口末端标记法（TUNEL）检测细胞凋亡，以Western印迹法检测miR-375靶基因肌营养素（myotrophin，V1）的表达。结果与其他3组比较，2’-O-me-375RNA组NIT-1脂性凋亡率最低（P〈0．01），同时V1表达水平最高（P〈0．01）。结论抑制内源性miR-375可降低胰岛β细胞的脂性凋亡。

Objective To investigate the effect of miR-375 inhibitied by 2＇-O-me-375 on lipoapoptosis of NIT-1 pancreatic β cells. Methods NIT-1 ceils were divided and treated according to the optimal condition：mock （ without lipofectamine）, lipofectamine （ transfected only with lipofectamine）, NC-miRNA （ transfected with negative control miRNA）, and 2＇-O-me-375 （transfected with 2＇-O-me-375 ）groups. 72 hours later, all ceils in each group were cultured with 500 μmol/L palmitate for 48 h. The percentage of apoptotic cells was detected by Hochest33342 staining and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling （TUNEL）. The protein expression of myotrophin （V1）, a target gene of miR-375, was detected by Western blotting. Results Compared to the other three groups, the cell apoptosis rate of 2＇-O-me-375 group was the lowest （P〈0.01） ,along with the highest V1 expression level（P〈0.01 ）. Conclusion Inhibition of miR-375 decreases pancreatic β-cell lipoapoptosis.