title: Glycation of paraoxonase 1 by high glucose instigates endoplasmic reticulum stress to induce endothelial dysfunction in vivo.
abstract: High-density lipoprotein (HDL) modulates low-density lipoprotein and cell membrane oxidation through the action of paraoxonase-1 (PON1). Endoplasmic reticulum (ER) stress has been linked to a wide range of human pathologies including diabetes, obesity, and atherosclerosis. Previous studies have reported that PON1 is glycated in diabetes. The aim of this study is to investigate whether and how PON1 glycation contributes to endothelial dysfunction in diabetes. ER stress markers were monitored by western blot. Endothelial function was determined by organ bath. Incubation of recombinant PON1 proteins with high glucose increased PON1 glycation and reduced PON1 activity. Exposure of HUVECs to glycated PON1 induced prolonged ER stress and reduced SERCA activity, which were abolished by tempol, apocynin, BAPTA, and p67 and p22 siRNAs. Chronic administration of amino guanidine or 4-PBA prevented endothelial dysfunction in STZ-injected rats. Importantly, injection of glycated PON1 but not native PON1 induced aberrant ER stress and endothelial dysfunction in rats, which were attenuated by tempol, BAPTA, and 4-PBA. In conclusion, glycation of PON1 by hyperglycemia induces endothelial dysfunction through ER stress. In perspectives, PON1 glycation is a novel risk factor of hyperglycemia-induced endothelial dysfunction. Therefore, inhibition of oxidative stress, chelating intracellular Ca2+, and ER chaperone would be considered to reduce vascular complications in diabetes.
authors.affiliation: Central Laboratory, Second Hospital, Jilin University, Changchun 130041, China.|Shenzhen Center for Chronic Disease Control, Shenzhen 518020, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Yu
authors.affiliation: Shenzhen Center for Chronic Disease Control, Shenzhen 518020, China.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Liu
authors.affiliation: Shenzhen Center for Chronic Disease Control, Shenzhen 518020, China.
authors.forename: Liru
authors.initials: L
authors.lastname: Feng
authors.affiliation: Shenzhen Center for Chronic Disease Control, Shenzhen 518020, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Yang
authors.affiliation: Shenzhen Center for Chronic Disease Control, Shenzhen 518020, China.
authors.forename: Weiye
authors.initials: W
authors.lastname: Yu
authors.affiliation: Shenzhen Center for Chronic Disease Control, Shenzhen 518020, China.
authors.forename: Tiejian
authors.initials: T
authors.lastname: Feng
authors.affiliation: Department of Pharmacology, College of Pharmacy, Xinxiang Medical University, Xinxiang, 453003, China.
authors.forename: Shuangxi
authors.initials: S
authors.lastname: Wang
authors.affiliation: Shenzhen Center for Chronic Disease Control, Shenzhen 518020, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Wang
authors.affiliation: Central Laboratory, Second Hospital, Jilin University, Changchun 130041, China.
authors.forename: Ning
authors.initials: N
authors.lastname: Liu
mesh_terms: D000818:Animals; D043303:Aryldialkylphosphatase / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D003921:Diabetes Mellitus, Experimental / Q000201:enzymology / Q000378:metabolism*; D059865:Endoplasmic Reticulum Stress / Q000502:physiology*; D004730:Endothelium, Vascular / Q000201:enzymology / Q000503:physiopathology; D006031:Glycosylation; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D006943:Hyperglycemia / Q000503:physiopathology; D008297:Male; D017207:Rats, Sprague-Dawley; D013481:Superoxides / Q000378:metabolism*
chemical_list: D013481:Superoxides; D043303:Aryldialkylphosphatase; D002118:Calcium