软脂酸对胰岛β细胞凋亡及Akt途径的影响

目的：探讨软脂酸（PA）对胰岛β细胞（MIN6细胞）凋亡及Akt信号途径的影响。方法：细胞采用小鼠胰岛素瘤细胞株MIN6,不同浓度PA（0-1．6mmol／L）干预24、48h,MTT、法测定各组细胞存活率。干预48h后Hoechst-PI染色法和Annexin—V／PI双标流式测定法测定各组细胞凋亡率,Western-blot法测定p-Akt、Akt、Bax、Bcl-2。结果：随着PA浓度的增高①MIN6细胞存活率逐渐减小、凋亡率逐渐增大;②MIN6细胞中p-Akt和Bcl-2的表达逐渐减少,而Akt、Bax无明显改变。结论：长时间PA作用引起MIN6细胞凋亡,并呈现一定的量效关系;这一效应可能是通过Akt／Bcl-2产生作用的。

The chronic effect of palmitic acid on apoptosis of pancreatic islet beta-cells and the mechanism

Aim： To investigate the chronic effect of palmitic acid （PA） on apoptosis of pancreatic islet β-cells and the possible mechanism. Methods： Insulinoma cell line（MIN6 cells） were used in this study. After being incubated in PA（0.1 - 1.6mml/L） for 24 and 48 hours, MTT method was used to evaluate the livability. After being incubated for 48 h, Hoechst-PI and Annexin-V-FITC/PI FACS were used to estimate the apoptosis in each group, Western-blotting assay was used to estimate the protein level of p-Akt, Akt, Bax and Bcl-2. Results： Chronic PA dose-dependently ①decreased the availability and increased the apoptosis of MIN6 cells; ②decreased the phosphorylation of Akt and Bcl-2, but had no significant effects on Akt and Bax. Conclusion： Chronic PA dose-dependently induced apoptosis of MIN6 cells, and this effect was possibly regulated by Akt/Bcl-2.