title: Na/K-ATPase signaling regulates collagen synthesis through microRNA-29b-3p in cardiac fibroblasts.
abstract: Chronic kidney disease (CKD) is accompanied by cardiac fibrosis, hypertrophy, and dysfunction, which are commonly referred to as uremic cardiomyopathy. Our previous studies found that Na/K-ATPase ligands or 5/6th partial nephrectomy (PNx) induces cardiac fibrosis in rats and mice. The current study used in vitro and in vivo models to explore novel roles for microRNA in this mechanism of cardiac fibrosis formation. To accomplish this, we performed microRNA profiling with RT-qPCR based arrays on cardiac tissue from rats subjected to marinobufagenin (MBG) infusion or PNx. The analysis showed that a series of fibrosis-related microRNAs were dysregulated. Among the dysregulated microRNAs, microRNA (miR)-29b-3p, which directly targets mRNA of collagen, was consistently reduced in both PNx and MBG-infused animals. In vitro experiments demonstrated that treatment of primary cultures of adult rat cardiac fibroblasts with Na/K-ATPase ligands induced significant increases in the fibrosis marker, collagen protein, and mRNA expression compared with controls, whereas miR-29b-3p expression decreased >50%. Transfection of miR-29b-3p mimics into cardiac fibroblasts inhibited cardiotonic steroids-induced collagen synthesis. Moreover, a specific Na/K-ATPase signaling antagonist, pNaKtide, prevented ouabain-induced increases in collagen synthesis and decreases in miR-29b-3p expression in these cells. In conclusion, these data are the first to indicate that signaling through Na/K-ATPase regulates miRNAs and specifically, miR-29b-3p expression both in vivo and in vitro. Additionally, these data indicate that miR-29b-3p expression plays an important role in the formation of cardiac fibrosis in CKD.
authors.affiliation: Department of Medicine, Division of Cardiovascular Medicine; Center for Hypertension and Personalized Medicine, College of Medicine, University of Toledo, Toledo, Ohio;
authors.forename: Christopher A
authors.identifier: http://orcid.org/0000-0002-0378-9882
authors.initials: CA
authors.lastname: Drummond
authors.affiliation: Department of Medicine, Division of Cardiovascular Medicine; Center for Hypertension and Personalized Medicine, College of Medicine, University of Toledo, Toledo, Ohio;
authors.forename: Michael C
authors.initials: MC
authors.lastname: Hill
authors.affiliation: Department of Medicine, Division of Cardiovascular Medicine; Center for Hypertension and Personalized Medicine, College of Medicine, University of Toledo, Toledo, Ohio;
authors.forename: Huilin
authors.initials: H
authors.lastname: Shi
authors.affiliation: Department of Medicine, Division of Cardiovascular Medicine; Center for Hypertension and Personalized Medicine, College of Medicine, University of Toledo, Toledo, Ohio;
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Fan
authors.affiliation: Department of Medicine, Division of Cardiovascular Medicine; Center for Hypertension and Personalized Medicine, College of Medicine, University of Toledo, Toledo, Ohio;
authors.forename: Jeffrey X
authors.initials: JX
authors.lastname: Xie
authors.affiliation: Department of Medicine, Division of Cardiovascular Medicine; Center for Hypertension and Personalized Medicine, College of Medicine, University of Toledo, Toledo, Ohio;
authors.forename: Steven T
authors.initials: ST
authors.lastname: Haller
authors.affiliation: Department of Medicine, Division of Cardiovascular Medicine; Center for Hypertension and Personalized Medicine, College of Medicine, University of Toledo, Toledo, Ohio;
authors.forename: David J
authors.initials: DJ
authors.lastname: Kennedy
authors.affiliation: Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia;
authors.forename: Jiang
authors.initials: J
authors.lastname: Liu
authors.affiliation: Departments of Pharmacology and Toxicology, Medicine, and Molecular and Genomics Core, University of Mississippi Medical Center, Jackson, Mississippi; and.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Garrett
authors.affiliation: Marshall Institute for Interdisciplinary Research, Marshall University, Huntington, West Virginia.
authors.forename: Zijian
authors.initials: Z
authors.lastname: Xie
authors.affiliation: Department of Medicine, Division of Cardiovascular Medicine; Center for Hypertension and Personalized Medicine, College of Medicine, University of Toledo, Toledo, Ohio;
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Cooper
authors.affiliation: Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia;
authors.forename: Joseph I
authors.initials: JI
authors.lastname: Shapiro
authors.affiliation: Department of Medicine, Division of Cardiovascular Medicine; Center for Hypertension and Personalized Medicine, College of Medicine, University of Toledo, Toledo, Ohio; Jiang.Tian@utoledo.edu.
authors.forename: Jiang
authors.initials: J
authors.lastname: Tian
mesh_terms: D000818:Animals; D002018:Bufanolides; D002316:Cardiotonic Agents / Q000494:pharmacology; D002478:Cells, Cultured; D003094:Collagen / Q000096:biosynthesis*; D015536:Down-Regulation / Q000235:genetics; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism*; D005355:Fibrosis; D020869:Gene Expression Profiling; D006352:Heart Ventricles / Q000187:drug effects / Q000378:metabolism; D008297:Male; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D009206:Myocardium / Q000378:metabolism / Q000473:pathology; D009392:Nephrectomy; D010042:Ouabain / Q000494:pharmacology; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction / Q000187:drug effects; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D013256:Steroids / Q000494:pharmacology; D014162:Transfection
chemical_list: D002018:Bufanolides; D002316:Cardiotonic Agents; C526366:MIRN29 microRNA, rat; D035683:MicroRNAs; D013256:Steroids; C093896:marinobufagenin; D010042:Ouabain; D003094:Collagen; D000254:Sodium-Potassium-Exchanging ATPase
keywords: Na/K-ATPase; cardiovascular disease; chronic kidney disease; fibrosis; microRNA (miRNA)