title: Indoxyl sulfate potentiates endothelial dysfunction via reciprocal role for reactive oxygen species and RhoA/ROCK signaling in 5/6 nephrectomized rats.
abstract: Accumulative indoxyl sulfate (IS) retained in chronic kidney disease (CKD) can potentiate vascular endothelial dysfunction, and herein, we aim at elucidating the underlying mechanisms from the perspective of possible association between reactive oxygen species (ROS) and RhoA/ROCK pathway. IS-treated nephrectomized rats are administered with antioxidants including NADPH oxidase inhibitor apocynin, SOD analog tempol, and mitochondrion-targeted SOD mimetic mito-TEMPO to scavenge ROS, or ROCK inhibitor fasudil to obstruct RhoA/ROCK pathway. First, we find in response to IS stimulation, antioxidants treatments suppress increased aortic ROCK activity and expression levels. Additionally, ROCK blockade prevent IS-induced increased NADPH oxidase expression (mainly p22phox and p47phox), mitochondrial and intracellular ROS (superoxide and hydrogen peroxide) generation, and decreased Cu/Zn-SOD expression in thoracic aortas. Apocynin, mito-TEMPO, and tempol also reverse these markers of oxidative stress. These results suggest that IS induces excessive ROS production and ROCK activation involving a circuitous relationship in which ROS activate ROCK and ROCK promotes ROS overproduction. Finally, ROS and ROCK depletion attenuate IS-induced decrease in nitric oxide (NO) production and eNOS expression levels, and alleviate impaired vasomotor responses including increased vasocontraction to phenylephrine and decreased vasorelaxation to acetylcholine, thereby preventing cardiovascular complications accompanied by CKD. Taken together, excessive ROS derived from NADPH oxidase and mitochondria coordinate with RhoA/ROCK activation in a form of positive reciprocal relationship to induce endothelial dysfunction through disturbing endothelium-dependent NO signaling upon IS stimulation in CKD status.
authors.affiliation: a Laboratory of Renal Disease , Putuo Hospital, Shanghai University of Traditional Chinese Medicine , Shanghai , China.
authors.forename: Shuang
authors.initials: S
authors.lastname: Chu
authors.affiliation: a Laboratory of Renal Disease , Putuo Hospital, Shanghai University of Traditional Chinese Medicine , Shanghai , China.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Mao
authors.affiliation: a Laboratory of Renal Disease , Putuo Hospital, Shanghai University of Traditional Chinese Medicine , Shanghai , China.
authors.forename: Hengjiang
authors.initials: H
authors.lastname: Guo
authors.affiliation: a Laboratory of Renal Disease , Putuo Hospital, Shanghai University of Traditional Chinese Medicine , Shanghai , China.
authors.forename: Li
authors.initials: L
authors.lastname: Wang
authors.affiliation: b Department of Nephrology , Putuo Hospital, Shanghai University of Traditional Chinese Medicine , Shanghai , China.
authors.forename: Zezheng
authors.initials: Z
authors.lastname: Li
authors.affiliation: b Department of Nephrology , Putuo Hospital, Shanghai University of Traditional Chinese Medicine , Shanghai , China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: b Department of Nephrology , Putuo Hospital, Shanghai University of Traditional Chinese Medicine , Shanghai , China.
authors.forename: Yunman
authors.initials: Y
authors.lastname: Wang
authors.affiliation: b Department of Nephrology , Putuo Hospital, Shanghai University of Traditional Chinese Medicine , Shanghai , China.
authors.forename: Hao
authors.initials: H
authors.lastname: Wang
authors.affiliation: c Department of Pharmacology, School of Pharmacy , Fudan University , Shanghai , China.
authors.forename: Xuemei
authors.initials: X
authors.lastname: Zhang
authors.affiliation: a Laboratory of Renal Disease , Putuo Hospital, Shanghai University of Traditional Chinese Medicine , Shanghai , China.|b Department of Nephrology , Putuo Hospital, Shanghai University of Traditional Chinese Medicine , Shanghai , China.
authors.forename: Wen
authors.initials: W
authors.lastname: Peng
mesh_terms: D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine / Q000008:administration & dosage / Q000031:analogs & derivatives; D000098:Acetophenones / Q000008:administration & dosage; D000818:Animals; D000975:Antioxidants / Q000008:administration & dosage*; D003497:Cyclic N-Oxides / Q000008:administration & dosage; D004730:Endothelium, Vascular / Q000187:drug effects; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D007200:Indican / Q000633:toxicity; D019255:NADPH Oxidases / Q000378:metabolism; D009569:Nitric Oxide / Q000096:biosynthesis; D052250:Nitric Oxide Synthase Type III / Q000096:biosynthesis; D009943:Organophosphorus Compounds / Q000008:administration & dosage; D018384:Oxidative Stress / Q000187:drug effects*; D010880:Piperidines / Q000008:administration & dosage; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism; D051436:Renal Insufficiency, Chronic / Q000139:chemically induced / Q000188:drug therapy* / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D013113:Spin Labels; D020741:rho GTP-Binding Proteins / Q000378:metabolism*; D054460:rho-Associated Kinases / Q000378:metabolism*
chemical_list: D000098:Acetophenones; D000975:Antioxidants; D003497:Cyclic N-Oxides; C555916:MitoTEMPO; D009943:Organophosphorus Compounds; D010880:Piperidines; D017382:Reactive Oxygen Species; D013113:Spin Labels; D009569:Nitric Oxide; D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; C056165:acetovanillone; D052250:Nitric Oxide Synthase Type III; C496316:Nos3 protein, rat; D019255:NADPH Oxidases; D054460:rho-Associated Kinases; C000621224:RhoA protein, rat; D020741:rho GTP-Binding Proteins; D007200:Indican; C049347:fasudil; C001803:tempol
keywords: Indoxyl sulfate; Rhoa/ROCK pathway; chronic kidney disease; endothelial dysfunction; reactive oxygen species