title: Inhibition of osteo/chondrogenic transformation of vascular smooth muscle cells by MgCl2 via calcium-sensing receptor.
abstract: The progression of vascular calcification, an active process promoted by osteo/chondrogenic transformation of vascular smooth muscle cells (VSMCs) is attenuated by activation of the calcium-sensing receptor (CASR). Recent in-vitro studies revealed that vascular calcification could be blunted by Mg, but the underlying mechanisms remained elusive. The present study explored whether the effects of MgCl2 on vascular calcification involve the CASR.
  
  
  
  Experiments were performed in primary human aortic smooth muscle cells (HAoSMCs) and in the mouse vascular calcification model of vitamin D3 overload.
  
  
  
  Phosphate-induced calcium deposition and mRNA expression of the osteogenic markers msh homeobox 2 (MSX2), CBFA1 (core-binding factor α 1), and ALPL (tissue-nonspecific alkaline phosphatase) in HAoSMCs were blunted by additional treatment with MgCl2. MgCl2 upregulated CASR mRNA expression in HAoSMCs in a dose-dependent manner. Furthermore, the inhibitory effects of MgCl2 on phosphate-induced calcium deposition and osteogenic markers mRNA expression were mimicked by the CASR agonist GdCl3 and reversed by additional treatment with the CASR antagonist NPS-2143 or by silencing of the CASR gene in HAoSMCs. MgCl2 also blunted the osteogenic transformation of VSMCs induced by hydroxyapatite particles. High-dosed cholecalciferol treatment induced vascular calcification and upregulated aortic osteogenic markers Msx2, Cbfa1 and Alpl and collagen type I (Col1a1), collagen type III (Col3a1) and fibronectin (Fbn) mRNA expression in mice, effects reduced by additional treatment with MgCl2. These effects were paralleled by increased aortic Casr mRNA expression in cholecalciferol-treated mice, which was further augmented by MgCl2.
  
  
  
  The protective effects of MgCl2 on osteo/chondrogenic transformation of VSMCs and vascular calcification involve regulation of CASR and CASR-dependent signaling.
authors.affiliation: aDepartment of Cardiology, Vascular Medicine and Physiology, University of Tübingen, Tübingen bDepartment of Internal Medicine and Cardiology, Charité University Medicine, Campus Virchow-Klinikum cBerlin Institute of Health (BIH) dDepartment of Internal Medicine and Cardiology, German Heart Center Berlin (DHZB), Berlin, Germany.
authors.forename: Ioana
authors.initials: I
authors.lastname: Alesutan
authors.forename: Rashad
authors.initials: R
authors.lastname: Tuffaha
authors.forename: Tilman
authors.initials: T
authors.lastname: Auer
authors.forename: Martina
authors.initials: M
authors.lastname: Feger
authors.forename: Burkert
authors.initials: B
authors.lastname: Pieske
authors.forename: Florian
authors.initials: F
authors.lastname: Lang
authors.forename: Jakob
authors.initials: J
authors.lastname: Voelkl
mesh_terms: D000469:Alkaline Phosphatase / Q000235:genetics; D000818:Animals; D001011:Aorta; D050071:Bone Density Conservation Agents / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D002478:Cells, Cultured; D002762:Cholecalciferol / Q000494:pharmacology; D020219:Chondrogenesis / Q000187:drug effects / Q000235:genetics; D024042:Collagen Type I / Q000235:genetics; D000090602:Collagen Type I, alpha 1 Chain; D024061:Collagen Type III / Q000235:genetics; D050659:Core Binding Factor Alpha 1 Subunit / Q000235:genetics / Q000378:metabolism; D017886:Durapatite / Q000494:pharmacology; D005353:Fibronectins / Q000235:genetics; D020868:Gene Silencing; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D015636:Magnesium Chloride / Q000494:pharmacology*; D051379:Mice; D009131:Muscle, Smooth, Vascular / Q000166:cytology; D032389:Myocytes, Smooth Muscle / Q000187:drug effects / Q000378:metabolism*; D010012:Osteogenesis / Q000187:drug effects / Q000235:genetics; D010710:Phosphates / Q000009:adverse effects / Q000494:pharmacology; D012333:RNA, Messenger / Q000378:metabolism; D044169:Receptors, Calcium-Sensing / Q000235:genetics* / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects; D015854:Up-Regulation / Q000187:drug effects; D061205:Vascular Calcification / Q000378:metabolism*
chemical_list: D050071:Bone Density Conservation Agents; C000609875:COL3A1 protein, mouse; D024042:Collagen Type I; D000090602:Collagen Type I, alpha 1 Chain; D024061:Collagen Type III; D050659:Core Binding Factor Alpha 1 Subunit; D005353:Fibronectins; D018398:Homeodomain Proteins; C084119:MSX2 protein; D010710:Phosphates; D012333:RNA, Messenger; D044169:Receptors, Calcium-Sensing; D015636:Magnesium Chloride; D002762:Cholecalciferol; D017886:Durapatite; C548267:ALPL protein, human; C510878:ALPL protein, mouse; D000469:Alkaline Phosphatase; D002118:Calcium