title: Inhibitory effect of unsaturated fatty acids on saturated fatty acid-induced apoptosis in human pancreatic β-cells: activation of caspases and ER stress induction.
abstract: OBJECTIVE
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Cell and Molecular Biology & Center for Research of Diabetes, Metabolism and Nutrition, Third Faculty of Medicine, Charles University, Ruská 87, Prague, Czech Republic.
authors.forename: Vlasta
authors.initials: V
authors.lastname: Němcová-Fürstová
authors.forename: Roger F L
authors.initials: RF
authors.lastname: James
authors.forename: Jan
authors.initials: J
authors.lastname: Kovář
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D020169:Caspases / Q000378:metabolism; D002461:Cell Line, Transformed; D045304:Cytochromes c / Q000032:analysis; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D004721:Endoplasmic Reticulum / Q000187:drug effects / Q000378:metabolism*; D000091342:Endoplasmic Reticulum Chaperone BiP; D004789:Enzyme Activation; D005229:Fatty Acids, Monounsaturated / Q000494:pharmacology*; D005434:Flow Cytometry; D015870:Gene Expression / Q000187:drug effects; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D050417:Insulin-Secreting Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism*; D019301:Oleic Acid / Q000494:pharmacology*; D012326:RNA Splicing; D012333:RNA, Messenger; D000071701:Regulatory Factor X Transcription Factors; D013229:Stearic Acids / Q000494:pharmacology*; D013312:Stress, Physiological; D051742:Transcription Factor CHOP / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D015854:Up-Regulation / Q000187:drug effects*; D000071717:X-Box Binding Protein 1
chemical_list: C497249:DDIT3 protein, human; D004268:DNA-Binding Proteins; D000091342:Endoplasmic Reticulum Chaperone BiP; D005229:Fatty Acids, Monounsaturated; D006360:Heat-Shock Proteins; D012333:RNA, Messenger; D000071701:Regulatory Factor X Transcription Factors; D013229:Stearic Acids; D014157:Transcription Factors; D000071717:X-Box Binding Protein 1; C000605543:XBP1 protein, human; D051742:Transcription Factor CHOP; C008757:palmitoleic acid; D019301:Oleic Acid; C031183:stearic acid; D045304:Cytochromes c; D020169:Caspases