title: The role of vascular peroxidase 1 in ox-LDL-induced vascular smooth muscle cell calcification.
abstract: Reactive oxygen species (ROS)-induced osteogenic differentiation of vascular smooth muscle cells (VSMCs) is associated with the pathogenesis of vascular calcification. Vascular peroxidase 1 (VPO1), a peroxidase in the cardiovascular system, utilizes the hydrogen peroxide (H2O2) produced by co-expressed NADPH oxidases to produce hypochlorous acid (HOCl) and catalyze peroxidative reactions. The aim of this study was to determine whether VPO1 plays a role in the osteogenic differentiation of VSMCs in the setting of the vascular calcification induced by oxidized low-density lipoprotein (ox-LDL). In cultured primary rat VSMCs, we observed that the expression of VPO1 was significantly increased in combination with increases in calcification, as demonstrated via increased mineralization, as well as increased alkaline phosphatase (ALP) activity and up-regulated runt-related transcription factor 2 (Runx2) expression in ox-LDL-treated cells. Ox-LDL-induced VSMC calcification and Runx2 expression were both inhibited by knockdown of VPO1 using a small interfering RNA or by an NADPH oxidase inhibitor. Moreover, the knockdown of VPO1 in VSMCs suppressed the production of HOCl and the phosphorylation of AKT, ERK and P38 MAPK. Furthermore, HOCl treatment facilitated the phosphorylation of AKT, ERK1/2 and P38 MAPK and the expression of Runx2, whereas LY294002 (a specific inhibitor of PI3K), U0126 (a specific inhibitor of ERK1/2) and SB203580 (a specific inhibitor of P38 MAPK) significantly attenuated the HOCl-induced up-regulation of Runx2. Collectively, these results demonstrated that VPO1 promotes ox-LDL-induced VSMC calcification via the VPO1/HOCl/PI3K/AKT, ERK1/2, and P38 MAPK/Runx2 signaling pathways.
authors.affiliation: Department of Cardiovascular Medicine, Xiangya Hospital, Central South University, Changsha, 410008, China.
authors.forename: Yixin
authors.initials: Y
authors.lastname: Tang
authors.affiliation: Department of Cardiovascular Medicine, Xiangya Hospital, Central South University, Changsha, 410008, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Xu
authors.affiliation: Department of Cardiovascular Medicine, Xiangya Hospital, Central South University, Changsha, 410008, China.
authors.forename: Haiyang
authors.initials: H
authors.lastname: Peng
authors.affiliation: Department of Cardiovascular Medicine, Xiangya Hospital, Central South University, Changsha, 410008, China.
authors.forename: Zhaoya
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Department of Cardiovascular Medicine, Xiangya Hospital, Central South University, Changsha, 410008, China.
authors.forename: Tianlun
authors.initials: T
authors.lastname: Yang
authors.affiliation: Department of Cardiovascular Medicine, Xiangya Hospital, Central South University, Changsha, 410008, China.
authors.forename: Zaixin
authors.initials: Z
authors.lastname: Yu
authors.affiliation: Division of Pulmonary, Allergy & Critical Care Medicine, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
authors.forename: Guangjie
authors.initials: G
authors.lastname: Cheng
authors.affiliation: Department of Pharmacology, School of Pharmaceutical Sciences, Central South University, Changsha, 410078, China.
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Cardiovascular Medicine, Xiangya Hospital, Central South University, Changsha, 410008, China. Electronic address: xyzgg2006@sina.com.
authors.forename: Guogang
authors.initials: G
authors.lastname: Zhang
authors.affiliation: Department of Cardiovascular Medicine, Xiangya Hospital, Central South University, Changsha, 410008, China. Electronic address: xysrz2010@sina.com.
authors.forename: Ruizheng
authors.initials: R
authors.lastname: Shi
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects / Q000201:enzymology / Q000473:pathology; D001018:Aortic Diseases / Q000139:chemically induced* / Q000201:enzymology / Q000235:genetics / Q000473:pathology / Q000517:prevention & control; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D050659:Core Binding Factor Alpha 1 Subunit / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D048049:Extracellular Signal-Regulated MAP Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D006420:Hemeproteins / Q000235:genetics / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000378:metabolism; D006997:Hypochlorous Acid / Q000378:metabolism; D008077:Lipoproteins, LDL / Q000633:toxicity*; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000187:drug effects* / Q000201:enzymology / Q000473:pathology; D032389:Myocytes, Smooth Muscle / Q000187:drug effects* / Q000201:enzymology / Q000473:pathology; D019255:NADPH Oxidases / Q000037:antagonists & inhibitors / Q000378:metabolism; D010012:Osteogenesis / Q000187:drug effects; D010544:Peroxidases / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D051057:Proto-Oncogene Proteins c-akt / Q000037:antagonists & inhibitors / Q000378:metabolism; D034622:RNA Interference; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction / Q000187:drug effects; D013997:Time Factors; D014162:Transfection; D061205:Vascular Calcification / Q000139:chemically induced* / Q000201:enzymology / Q000235:genetics / Q000473:pathology / Q000517:prevention & control; D048051:p38 Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D050659:Core Binding Factor Alpha 1 Subunit; D006420:Hemeproteins; D008077:Lipoproteins, LDL; D047428:Protein Kinase Inhibitors; C493717:Runx2 protein, rat; C099252:oxidized low density lipoprotein; D006997:Hypochlorous Acid; D006861:Hydrogen Peroxide; C573339:vascular peroxidase, rat; D010544:Peroxidases; D019255:NADPH Oxidases; D051057:Proto-Oncogene Proteins c-akt; D048049:Extracellular Signal-Regulated MAP Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D000469:Alkaline Phosphatase
keywords: Osteogenic differentiation; Oxidized low-density lipoprotein; Vascular calcification; Vascular peroxidase 1; Vascular smooth muscle cells