title: Trans-11 vaccenic acid improves insulin secretion in models of type 2 diabetes in vivo and in vitro.
abstract: METHODS
  Trans-11 vaccenic acid (VA) is a fatty acid produced by ruminants entering the human food supply through meat and dairy products, which appears not to have the health risks associated with industrially produced trans-fatty acids. In this study, we investigated the effect of VA on insulin secretion in vivo in rats and in vitro in human and rat islets after diabetogenic insult.
  
  
  RESULTS
  Hyperglycemic clamp showed that VA dietary supplementation for 8 weeks significantly increased glucose turnover in rats with type 2 diabetes (T2D), accompanied by an elevated plasma C-peptide concentration, indicating improved insulin secretion. The β-cell area and proliferation rate were higher in T2D+VA than T2D group. Isolated islets from T2D+VA rats had higher glucose-stimulated insulin secretion (GSIS) than T2D group. In vitro, VA treatment for 24 and 48 h significantly enhanced GSIS in rat and human islets after diabetogenic challenges. The mRNA expression of G-protein-coupled receptor 40 (GPR40) and regenerating islet-derived 1α (REG-1α) were consistently increased by VA in both rat and human islets.
  
  
  CONCLUSIONS
  These results indicate that VA may improve insulin secretion and growth of islets in T2D, at least partly by altering GPR40 and REG-1α mRNA expression.
authors.affiliation: Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada.
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada.
authors.forename: Joel
authors.initials: J
authors.lastname: Gupta
authors.affiliation: Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada.
authors.forename: Matthew
authors.initials: M
authors.lastname: Kerslake
authors.affiliation: Alberta Diabetes Institute, Surgical-Medical Research Institute, Department of Surgery, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada.
authors.forename: Gina
authors.initials: G
authors.lastname: Rayat
authors.affiliation: Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada.
authors.forename: Spencer D
authors.initials: SD
authors.lastname: Proctor
authors.affiliation: Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada.|Department of Physiology, University of Alberta, Edmonton, AB, Canada.
authors.forename: Catherine B
authors.initials: CB
authors.lastname: Chan
mesh_terms: D000368:Aged; D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects; D003921:Diabetes Mellitus, Experimental / Q000178:diet therapy / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000178:diet therapy* / Q000378:metabolism / Q000473:pathology; D059305:Diet, High-Fat / Q000009:adverse effects; D019587:Dietary Supplements; D005947:Glucose / Q000378:metabolism; D006801:Humans; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000187:drug effects / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009829:Oleic Acids / Q000097:blood / Q000494:pharmacology*; D019308:Palmitic Acid / Q000494:pharmacology; D017207:Rats, Sprague-Dawley; D043562:Receptors, G-Protein-Coupled / Q000235:genetics / Q000378:metabolism; D016559:Tacrolimus / Q000494:pharmacology
chemical_list: C473035:G-protein-coupled receptor 40, rat; D007328:Insulin; D009829:Oleic Acids; D043562:Receptors, G-Protein-Coupled; D019308:Palmitic Acid; C050413:11-octadecenoic acid; D005947:Glucose; D016559:Tacrolimus
keywords: Insulin secretion; Islets; Ruminant trans-fatty acids; Trans-11 vaccenic acid; Type 2 diabetes