Inhibitory Effect of Unsaturated Fatty Acids on Saturated Fatty Acid-Induced Apoptosis in Human Pancreatic β-Cells: Activation of Caspases and ER Stress Induction

Cellular Physiology and Biochemistry

关键词: Fatty acids;    Apoptosis;    β-cell;    Caspases;    Endo-plasmic reticulum stress;   

DOI  :  10.1159/000329954

学科分类：分子生物学，细胞生物学和基因

来源: S Karger AG

【 摘 要 】

Aims In this study we have tested the effect of unsaturated fatty acids on the proapoptotic effects of saturated fatty acids in the human pancreatic β-cells NES2Y. Results We found that unsaturated palmitoleic and oleic acid at a concentration of 0.2 mM and higher are able to completely inhibit the proapoptotic effect of their counterpart saturated palmitic and stearic acid at a concentration of 1 mM. Apoptosis induced by stearic acid was associated with significant activation of caspase-6, -7, -9, -2 and -8, but not with significant activation of caspase-3. The activation of caspases was blocked by coincubation with oleic acid. Stearic acid treatment was not associated with a significant change in mitochondrial membrane potential, reactive oxygen species level and with cytochrome c release from mitochondria. Furthermore, stearic acid treatment was not associated with changes in p21^WAF1/CIP1, PIDD, Fas receptor and Fas ligand expression. However, we detected endoplasmic reticulum (ER) stress markers, i. e. a significant upregulation of BiP and CHOP expression as well as XBP1 mRNA splicing. These changes were inhibited by coincubation with oleic acid. Conclusion Presented data indicate that oleic acid inhibits apoptosis induction by stearic acid in NES2Y cells upstream of caspase activation and ER stress induction. It does not involve an interference with the mitochondrial pathway of apoptosis induction, with p53 activation and PIDD expression as well as with Fas receptor and Fas ligand expression.

【 授权许可】

CC BY-NC-ND