title: Vitamin D suppresses oxidative stress-induced microparticle release by human umbilical vein endothelial cells.
abstract: Endothelial microparticle (MP) release was increased in numerous cardiovascular diseases including preeclampsia. Oxidative stress is a potent inducer of endothelial dysfunction. In this study, we aimed to investigate if vitamin D could protect endothelial cells (ECs) from MP release induced by oxidative stress. Endothelial cell (from human umbilical vein) oxidative stress was induced by cultivation of cells under lowered oxygen condition (2%O2) for 48 h and cells cultured under standard condition (21%O2) served as control. 1,25(OH)2D3 was used as bioactive vitamin D. Using annexin-V as a marker of released MP assessed by flow cytometry and cytochrome c reduction assay to measure EC superoxide generation, we found that MP release and superoxide generation were significantly increased when cells were cultured under 2%O2, which could be significantly inhibited by 1,25(OH)2D3. To study the potential mechanisms of 1,25(OH)2D3 protective effects on ECs, EC expression of endothelial nitric oxide synthase (eNOS), p-eNOSSer1177, p-eNOSThr495, caveolin-1, extracellular signal-regulated kinase (ERK), p-ERK, Akt, p-AktSer473, Rho-associated coiled-coil protein kinase 1 (ROCK1), and vitamin D receptor were determined. Microparticle expression of eNOS and caveolin-1 were also determined. We found that under lowered oxygen condition, 1,25(OH)2D3 could upregulate EC eNOS, p-eNOSSer1177, and p-AktSer473 expression, but inhibit cleaved ROCK1 expression. The upregulatory and inhibitory effects induced by 1,25(OH)2D3 were dose dependent. Strikingly, we also found that oxidative stress-induced decrease in ratio of eNOS and caveolin-1 expression in MP could be attenuated when 1,25(OH)2D3 was present in culture. These results suggest that upregulation of eNOSSer1177 and AktSer473 phosphorylation and inhibition of ROCK1 cleavage in EC and modulation of eNOS and caveolin-1 expression in MP could be plausible mechanisms of vitamin D protective effects on ECs.
authors.affiliation: Department of Obstetrics and Gynecology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, Louisiana, USA.|Department of Cardiology, The First Affiliated Hospital Harbin Medical University, Harbin, China.
authors.forename: Xiuyue
authors.initials: X
authors.lastname: Jia
authors.affiliation: Department of Obstetrics and Gynecology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, Louisiana, USA.
authors.forename: Jie
authors.initials: J
authors.lastname: Xu
authors.affiliation: Department of Obstetrics and Gynecology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, Louisiana, USA.
authors.forename: Yang
authors.initials: Y
authors.lastname: Gu
authors.affiliation: Department of Pathology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, Louisiana, USA.
authors.forename: Xin
authors.initials: X
authors.lastname: Gu
authors.affiliation: Department of Cardiology, The First Affiliated Hospital Harbin Medical University, Harbin, China.
authors.forename: Weimin
authors.initials: W
authors.lastname: Li
authors.affiliation: Department of Obstetrics and Gynecology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, Louisiana, USA.
authors.forename: Yuping
authors.initials: Y
authors.lastname: Wang
mesh_terms: D051242:Caveolin 1 / Q000378:metabolism; D055252:Cell-Derived Microparticles; D004353:Drug Evaluation, Preclinical; D042783:Endothelial Cells / Q000187:drug effects* / Q000378:metabolism; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D000860:Hypoxia / Q000378:metabolism; D052250:Nitric Oxide Synthase Type III / Q000378:metabolism; D018384:Oxidative Stress; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D014807:Vitamin D / Q000494:pharmacology / Q000627:therapeutic use*; D054460:rho-Associated Kinases / Q000378:metabolism
chemical_list: D051242:Caveolin 1; D014807:Vitamin D; C496314:NOS3 protein, human; D052250:Nitric Oxide Synthase Type III; D051057:Proto-Oncogene Proteins c-akt; C515851:ROCK1 protein, human; D054460:rho-Associated Kinases; D048049:Extracellular Signal-Regulated MAP Kinases
keywords: Akt; ROCK; eNOS; endothelial cells; microparticles; vitamin D