title: Nitrative Stress Participates in Endothelial Progenitor Cell Injury in Hyperhomocysteinemia.
abstract: In order to investigate the role of nitrative stress in vascular endothelial injury in hyperhomocysteinemia (HHcy), thirty healthy adult female Wistar rats were randomly divided into three groups: control, hyperhomocysteinemia model, and hyperhomocysteinemia with FeTMPyP (peroxynitrite scavenger) treatment. The endothelium-dependent dilatation of thoracic aorta in vitro was determined by response to acetylcholine (ACh). The histological changes in endothelium were assessed by HE staining and scanning electron microscopy (SEM). The expression of 3-nitrotyrosine (NT) in thoracic aorta was demonstrated by immunohistochemistry and immunofluorescence, and the number of circulating endothelial progenitor cells (EPCs) was quantified by flow cytometry. Hyperhomocysteinemia caused significant endothelial injury and dysfunction including vasodilative and histologic changes, associated with higher expression of NT in thoracic aorta. FeTMPyP treatment reversed these injuries significantly. Further, the effect of nitrative stress on cultured EPCs in vitro was investigated by administering peroxynitrite donor (3-morpholino-sydnonimine, SIN-1) and peroxynitrite scavenger (FeTMPyP). The roles of nitrative stress on cell viability, necrosis and apoptosis were evaluated with 3-(4,5-dimethylthiazol)-2,5-diphenyl tetrazolium (MTT) assay, lactate dehydrogenase (LDH) release assay and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay, respectively. Also, the phospho-eNOS expression and tube formation in Matrigel of cultured EPCs was detected. Our data showed that the survival of EPCs was much lower in SIN-1 group than in vehicle group, both the apoptosis and necrosis of EPCs were much more severe, and the p-eNOS expression and tube formation in Matrigel were obviously declined. Subsequent pretreatment with FeTMPyP reversed these changes. Further, pretreatment with FeTMPyP reversed homocysteine-induced EPC injury. In conclusion, this study indicates that nitrative stress plays a role in vascular endothelial injury in hyperhomocysteinemia, as well as induces endothelial progenitor cell injury directly.
authors.affiliation: Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China.|Beijing Key Laboratory of Metabolic Disorders Related Cardiovascular Diseases, Capital Medical University, Beijing, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Dong
authors.affiliation: Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China.|Beijing Key Laboratory of Metabolic Disorders Related Cardiovascular Diseases, Capital Medical University, Beijing, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Sun
authors.affiliation: Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China.|Beijing Key Laboratory of Metabolic Disorders Related Cardiovascular Diseases, Capital Medical University, Beijing, China.
authors.forename: Teng
authors.initials: T
authors.lastname: Liu
authors.affiliation: Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China.|Beijing Key Laboratory of Metabolic Disorders Related Cardiovascular Diseases, Capital Medical University, Beijing, China.
authors.forename: Huanyuan
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China.|Beijing Key Laboratory of Metabolic Disorders Related Cardiovascular Diseases, Capital Medical University, Beijing, China.
authors.forename: Kun
authors.initials: K
authors.lastname: Jiao
authors.affiliation: Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China.|Beijing Key Laboratory of Metabolic Disorders Related Cardiovascular Diseases, Capital Medical University, Beijing, China.
authors.forename: Jiahui
authors.initials: J
authors.lastname: Xu
authors.affiliation: Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China.|Beijing Key Laboratory of Metabolic Disorders Related Cardiovascular Diseases, Capital Medical University, Beijing, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Liu
authors.affiliation: Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China.|Beijing Key Laboratory of Metabolic Disorders Related Cardiovascular Diseases, Capital Medical University, Beijing, China.
authors.forename: Huirong
authors.initials: H
authors.lastname: Liu
authors.affiliation: Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China.|Beijing Key Laboratory of Metabolic Disorders Related Cardiovascular Diseases, Capital Medical University, Beijing, China.
authors.forename: Wen
authors.initials: W
authors.lastname: Wang
mesh_terms: D000818:Animals; D066026:Endothelial Progenitor Cells / Q000378:metabolism* / Q000473:pathology*; D005260:Female; D005434:Flow Cytometry; D020138:Hyperhomocysteinemia / Q000378:metabolism*; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D011897:Random Allocation; D017208:Rats, Wistar; D014443:Tyrosine / Q000031:analogs & derivatives / Q000378:metabolism
chemical_list: C002744:3-nitrotyrosine; D014443:Tyrosine