title: Adiponectin protects endothelial cells from the damages induced by the intermittent high level of glucose.
abstract: Globular adiponectin (gAd) has anti-atherogenic effects on the vascular wall. Intermittent hyperglycemia induces endothelial cells (ECs) injury but the physiological factors that may protect against ECs damage are largely unknown. In the present study, we investigated the effect of gAd on ECs dysfunction induced by intermittent high glucose. The gAd significantly attenuated intermittent high glucose-induced apoptosis and oxidative stress in human umbilical vein endothelial cells. This was achieved by decreasing caspase-3 and 3-nitrotyrosine protein expression, increasing nitric oxide (NO) secretion and phosphorylation of Akt, AMPK, and endothelial nitric oxide synthase protein expression. Pretreatment with a phosphatidylinositol 3' kinase (PI3K) inhibitor, LY294002, partly reversed adiponectin's anti-apoptotic effect. Taken together, our results indicate that gAd acts as a critical physiological factor which protects against fluctuating high glucose-induced endothelial damage. It may act via attenuating apoptosis and increasing synthesis of NO through both the PI3K/AKT and AMPK signaling pathway to reduce oxidative stress and cell apoptosis.
authors.affiliation: Department of Metabolism & Endocrinology, The First Affiliated Hospital, University of South China, 69 Chuanshan Road, Hengyang, 421001, People's Republic of China.
authors.forename: Xinhua
authors.initials: X
authors.lastname: Xiao
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Dong
authors.forename: Jing
authors.initials: J
authors.lastname: Zhong
authors.forename: Renxian
authors.initials: R
authors.lastname: Cao
authors.forename: Xiang
authors.initials: X
authors.lastname: Zhao
authors.forename: Gebo
authors.initials: G
authors.lastname: Wen
authors.forename: Jianghua
authors.initials: J
authors.lastname: Liu
mesh_terms: D052242:Adiponectin / Q000502:physiology; D000704:Analysis of Variance; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D053148:Caspase 3 / Q000378:metabolism; D002478:Cells, Cultured; D005947:Glucose / Q000378:metabolism / Q000494:pharmacology*; D061307:Human Umbilical Vein Endothelial Cells / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D009569:Nitric Oxide / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects / Q000502:physiology*; D017510:Protein Folding; D015290:Second Messenger Systems / Q000187:drug effects / Q000502:physiology; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D014443:Tyrosine / Q000031:analogs & derivatives / Q000378:metabolism
chemical_list: C499918:ADIPOQ protein, human; D052242:Adiponectin; D009569:Nitric Oxide; C002744:3-nitrotyrosine; D014443:Tyrosine; D053148:Caspase 3; D005947:Glucose