title: Adiponectin abates diabetes-induced endothelial dysfunction by suppressing oxidative stress, adhesion molecules, and inflammation in type 2 diabetic mice.
abstract: Adiponectin (APN) can confer protection against metabolism-related illnesses in organs such as fat, the liver, and skeletal muscle. However, it is unclear whether APN improves endothelial-dependent nitric oxide-mediated vasodilation in type 2 diabetes and, if so, by what mechanism. We tested whether exogenous APN delivery improves endothelial function in type 2 diabetic mice and explored the mechanisms underlying the observed improvement. To test the hypothesis, we injected adenovirus APN (Ad-APN) or adenovirus β-galactosidase (Ad-βgal; control virus) via the tail vein in control (m Lepr(db)) and diabetic (Lepr(db); db/db) mice and studied vascular function of the aorta ex vivo. Ad-APN improved endothelial-dependent vasodilation in db/db mice compared with Ad-βgal, whereas Ad-APN had no further improvement on endothelial function in control mice. This improvement was completely inhibited by a nitric oxide synthase inhibitor (N(G)-nitro-l-arginine methyl ester). Serum triglyceride and total cholesterol levels were increased in db/db mice, and Ad-APN significantly reduced triglyceride levels but not total cholesterol levels. Immunoblot results showed that interferon-γ, gp91(phox), and nitrotyrosine were markedly increased in the aorta of db/db mice. Ad-APN treatment decreased the expression of these proteins. In addition, mRNA expression of TNF-α, IL-6, and ICAM-1 was elevated in db/db mice, and Ad-APN treatment decreased these expressions in the aorta. Our findings suggest that APN may contribute to an increase in nitric oxide bioavailability by decreasing superoxide production as well as by inhibiting inflammation and adhesion molecules in the aorta in type 2 diabetic mice.
authors.affiliation: Department of Internal Medicine, University of Missouri, Columbia, USA. sltdd@mail.missouri.edu
authors.forename: Sewon
authors.initials: S
authors.lastname: Lee
authors.forename: Hanrui
authors.initials: H
authors.lastname: Zhang
authors.forename: Jianping
authors.initials: J
authors.lastname: Chen
authors.forename: Kevin C
authors.initials: KC
authors.lastname: Dellsperger
authors.forename: Michael A
authors.initials: MA
authors.lastname: Hill
authors.forename: Cuihua
authors.initials: C
authors.lastname: Zhang
mesh_terms: D000256:Adenoviridae / Q000235:genetics; D052242:Adiponectin / Q000235:genetics* / Q000494:pharmacology*; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal; D001011:Aorta / Q000502:physiology; D001774:Blood Chemical Analysis; D015153:Blotting, Western; D015815:Cell Adhesion Molecules / Q000096:biosynthesis*; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000188:drug therapy* / Q000235:genetics; D003925:Diabetic Angiopathies / Q000188:drug therapy* / Q000473:pathology; D015536:Down-Regulation; D005455:Fluorescent Antibody Technique; D007150:Immunohistochemistry; D007249:Inflammation / Q000188:drug therapy* / Q000473:pathology; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D018384:Oxidative Stress / Q000235:genetics*; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D014162:Transfection; D001616:beta-Galactosidase / Q000235:genetics / Q000378:metabolism; D014841:von Willebrand Factor / Q000096:biosynthesis
chemical_list: D052242:Adiponectin; D000894:Anti-Inflammatory Agents, Non-Steroidal; D015815:Cell Adhesion Molecules; D012333:RNA, Messenger; D014841:von Willebrand Factor; D001616:beta-Galactosidase