title: Adiponectin is expressed in the pancreas of high-fat-diet-fed mice and protects pancreatic endothelial function during the development of type 2 diabetes.
abstract: OBJECTIVE
  Adiponectin levels in skeletal muscle and adipose tissue have been reported to be involved in insulin resistance in rats fed with a high-fat diet (HFD). Our objective was to explore whether adiponectin is also expressed in the pancreas and what its potential role is during the development of type 2 diabetes (T2D) in outbred CD-1 mice.
  
  
  METHODS
  Male 4-week-old outbred CD-1 mice were fed an HFD to induce a polygenic model of human T2D. Adiponectin expression was examined in mouse pancreas by quantitative real-time polymerase chain reaction (qPCR), western blots and immunofluorescence analyses. Human umbilical vein endothelium cells (HUVECs) were transfected with an adiponectin-expressing lentivirus to determine the effect of adiponectin on angiogenic function in vitro.
  
  
  RESULTS
  Feeding mice an HFD for 9weeks resulted in constant hyperglycaemia, obesity, impaired glucose tolerance and insulin resistance. Additional hyperinsulinaemia emerged in mice fed an HFD for 18weeks. Interestingly, aberrant expression of adiponectin was detectable in the pancreatic vascular endothelial cells (VECs) of mice fed with an HFD, but not in mice fed with regular chow (RC). Expression levels of pancreatic adiponectin varied during the development of T2D. This extraordinary expression of adiponectin in pancreatic VECs played a role in protecting endothelial function against potential damage by HFD. Our in vitro study has demonstrated that adiponectin promotes angiogenic function.
  
  
  CONCLUSIONS
  These results reveal for the first time that adiponectin is expressed in pancreatic VECs of HFD-fed mice during the development of T2D as a protective adaptation in response to the HFD.
authors.affiliation: Department of Cell Biology, Peking University Health Science Center, Beijing 100191, China.
authors.forename: X-X
authors.initials: XX
authors.lastname: Liu
authors.affiliation: Department of Biochemistry and Molecular Biology, Peking University Health Science Center, Beijing 100191, China.
authors.forename: K-Y
authors.initials: KY
authors.lastname: Liu
authors.affiliation: Department of Cell Biology, Peking University Health Science Center, Beijing 100191, China.
authors.forename: P
authors.initials: P
authors.lastname: Li
authors.affiliation: Department of Cell Biology, Peking University Health Science Center, Beijing 100191, China.
authors.forename: S
authors.initials: S
authors.lastname: Han
authors.affiliation: Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, IL 60607, USA. Electronic address: pengxd@uic.edu.
authors.forename: X-D
authors.initials: XD
authors.lastname: Peng
authors.affiliation: Department of Cell Biology, Peking University Health Science Center, Beijing 100191, China. Electronic address: shenli@bjmu.edu.cn.
authors.forename: L
authors.initials: L
authors.lastname: Shen
mesh_terms: D052242:Adiponectin / Q000378:metabolism*; D000818:Animals; D021461:Animals, Outbred Strains; D015153:Blotting, Western; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism*; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism* / Q000503:physiopathology; D059305:Diet, High-Fat; D004730:Endothelium, Vascular / Q000378:metabolism* / Q000503:physiopathology; D004734:Energy Metabolism; D005455:Fluorescent Antibody Technique; D018149:Glucose Intolerance / Q000209:etiology / Q000378:metabolism; D006943:Hyperglycemia / Q000378:metabolism* / Q000503:physiopathology; D006946:Hyperinsulinism / Q000209:etiology / Q000378:metabolism; D007333:Insulin Resistance; D008297:Male; D051379:Mice; D009765:Obesity / Q000378:metabolism* / Q000503:physiopathology; D047495:PPAR gamma / Q000378:metabolism; D010179:Pancreas / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D060888:Real-Time Polymerase Chain Reaction; D015398:Signal Transduction; D015854:Up-Regulation
chemical_list: D052242:Adiponectin; D047495:PPAR gamma
keywords: Adiponectin; High-fat diet; Pancreas; Type 2 diabetes; Vascular endothelial cells