title: Bone Morphogenetic Protein Signaling Is Required for Aortic Valve Calcification.
abstract: Calcific aortic valve disease (CAVD) is the most prevalent type of heart valve disease, affecting ≈2% of the US population. CAVD is characterized by the presence of calcific nodules, resulting in aortic valve (AoV) stenosis; however, the underlying mechanisms driving disease remain unknown. Studies of human diseased AoV provide initial evidence that bone morphogenetic protein (BMP) signaling, essential for normal bone formation, is activated during CAVD. Mice deficient in Klotho, an FGF23 transmembrane coreceptor, exhibit premature aging and develop AoV calcific nodules as occurs in human CAVD. The role of BMP signaling in the development of CAVD was examined in porcine aortic valve interstitial cells (VICs) and Klotho(-/-) mice.
  
  
  
  We show that activation of BMP signaling, as indicated by pSmad1/5/8 expression, precedes and later localizes with AoV calcification in Klotho(-/-) mice. In addition, cellular and extracellular matrix changes resembling features of normal bone formation are accompanied by increased osteochondrogenic gene induction in calcified Klotho(-/-) AoV. Likewise, osteogenic media treatment of porcine VICs results in BMP pathway activation, increased osteochondrogenic gene induction, and formation of calcific nodules in vitro. We demonstrate that genetic inactivation of the BMP type IA receptor in Klotho(-/-) aortic VICs, as well as BMP pathway inhibition of osteogenic media-treated aortic VICs in vitro, results in the inhibition of AoV calcification.
  
  
  
  BMP signaling and osteochondrogenic gene induction are active in calcified Klotho(-/-) AoV in vivo and calcified porcine aortic VICs in vitro. Importantly, BMP signaling is required for the development of AoV calcification in vitro and in vivo.
authors.affiliation: From the Heart Institute, Cincinnati Children's Hospital Medical Center, OH (M.V.G.-S., E.E.W.-S., K.R.H., K.E.Y.); Department of Pediatrics, College of Medicine, University of Cincinnati, OH (M.V.G.-S., K.E.Y.); and Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN (S.J.C.).
authors.forename: M Victoria
authors.initials: MV
authors.lastname: Gomez-Stallons
authors.affiliation: From the Heart Institute, Cincinnati Children's Hospital Medical Center, OH (M.V.G.-S., E.E.W.-S., K.R.H., K.E.Y.); Department of Pediatrics, College of Medicine, University of Cincinnati, OH (M.V.G.-S., K.E.Y.); and Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN (S.J.C.).
authors.forename: Elaine E
authors.initials: EE
authors.lastname: Wirrig-Schwendeman
authors.affiliation: From the Heart Institute, Cincinnati Children's Hospital Medical Center, OH (M.V.G.-S., E.E.W.-S., K.R.H., K.E.Y.); Department of Pediatrics, College of Medicine, University of Cincinnati, OH (M.V.G.-S., K.E.Y.); and Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN (S.J.C.).
authors.forename: Keira R
authors.initials: KR
authors.lastname: Hassel
authors.affiliation: From the Heart Institute, Cincinnati Children's Hospital Medical Center, OH (M.V.G.-S., E.E.W.-S., K.R.H., K.E.Y.); Department of Pediatrics, College of Medicine, University of Cincinnati, OH (M.V.G.-S., K.E.Y.); and Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN (S.J.C.).
authors.forename: Simon J
authors.initials: SJ
authors.lastname: Conway
authors.affiliation: From the Heart Institute, Cincinnati Children's Hospital Medical Center, OH (M.V.G.-S., E.E.W.-S., K.R.H., K.E.Y.); Department of Pediatrics, College of Medicine, University of Cincinnati, OH (M.V.G.-S., K.E.Y.); and Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN (S.J.C.). Katherine.Yutzey@cchmc.org.
authors.forename: Katherine E
authors.initials: KE
authors.lastname: Yutzey
mesh_terms: D000818:Animals; D001021:Aortic Valve / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology*; D001024:Aortic Valve Stenosis / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D052005:Bone Morphogenetic Protein Receptors, Type I / Q000172:deficiency / Q000235:genetics; D019485:Bone Morphogenetic Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism*; D002114:Calcinosis / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D002478:Cells, Cultured; D020219:Chondrogenesis; D004195:Disease Models, Animal; D005109:Extracellular Matrix / Q000378:metabolism; D005260:Female; D000089703:Fibroblast Growth Factor-23; D005786:Gene Expression Regulation; D020022:Genetic Predisposition to Disease; D005966:Glucuronidase / Q000172:deficiency / Q000235:genetics; D000090265:Klotho Proteins; D008297:Male; D018345:Mice, Knockout; D010012:Osteogenesis; D010641:Phenotype; D010766:Phosphorylation; D011720:Pyrazoles / Q000494:pharmacology; D011743:Pyrimidines / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects; D051898:Smad1 Protein / Q000378:metabolism; D051902:Smad5 Protein / Q000378:metabolism*; D051904:Smad8 Protein / Q000378:metabolism; D013552:Swine
chemical_list: D019485:Bone Morphogenetic Proteins; C000717427:FGF23 protein, human; C000717428:Fgf23 protein, mouse; C554430:LDN 193189; D011720:Pyrazoles; D011743:Pyrimidines; D051898:Smad1 Protein; C497401:Smad1 protein, mouse; D051902:Smad5 Protein; C497798:Smad5 protein, mouse; D051904:Smad8 Protein; C491621:Smad9 protein, mouse; D000089703:Fibroblast Growth Factor-23; C498212:Bmpr1a protein, mouse; D052005:Bone Morphogenetic Protein Receptors, Type I; D005966:Glucuronidase; D000090265:Klotho Proteins
keywords: BMP; Klotho; aortic valve calcification; heart valve disease; osteogenesis