High-efficiency reprogramming of fibroblasts into cardiomyocytes requires suppression of pro-fibrotic signalling.
Direct reprogramming of fibroblasts into cardiomyocytes by forced expression of cardiomyogenic factors, GMT (GATA4, Mef2C, Tbx5) or GHMT (GATA4, Hand2, Mef2C, Tbx5), has recently been demonstrated, suggesting a novel therapeutic strategy for cardiac repair. However, current approaches are inefficient. Here we demonstrate that pro-fibrotic signalling potently antagonizes cardiac reprogramming. Remarkably, inhibition of pro-fibrotic signalling using small molecules that target the transforming growth factor-β or Rho-associated kinase pathways converts embryonic fibroblasts into functional cardiomyocyte-like cells, with the efficiency up to 60%. Conversely, overactivation of these pro-fibrotic signalling networks attenuates cardiac reprogramming. Furthermore, inhibition of pro-fibrotic signalling dramatically enhances the kinetics of cardiac reprogramming, with spontaneously contracting cardiomyocytes emerging in less than 2 weeks, as opposed to 4 weeks with GHMT alone. These findings provide new insights into the molecular mechanisms underlying cardiac conversion of fibroblasts and would enhance efforts to generate cardiomyocytes for clinical applications.
Division of Cardiology, Department of Medicine, University of Colorado School of Medicine, 12700 E. 19th Avenue, B139, Aurora, Colorado 80045, USA.
Yuanbiao
Y
Zhao
Division of Cardiology, Department of Medicine, University of Colorado School of Medicine, 12700 E. 19th Avenue, B139, Aurora, Colorado 80045, USA.
Pilar
P
Londono
Division of Cardiology, Department of Medicine, University of Colorado School of Medicine, 12700 E. 19th Avenue, B139, Aurora, Colorado 80045, USA.
Yingqiong
Y
Cao
Department of Physiology and Biophysics, University of Colorado School of Medicine, 12800 E. 19th Avenue, Aurora, Colorado 80045, USA.
Emily J
EJ
Sharpe
Division of Cardiology, Department of Medicine, University of Colorado School of Medicine, 12700 E. 19th Avenue, B139, Aurora, Colorado 80045, USA.|Department of Physiology and Biophysics, University of Colorado School of Medicine, 12800 E. 19th Avenue, Aurora, Colorado 80045, USA.
Catherine
C
Proenza
Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, 12801 E. 17th Avenue, Aurora, Colorado 80045, USA.
Rebecca
R
O'Rourke
Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, 12801 E. 17th Avenue, Aurora, Colorado 80045, USA.
Kenneth L
KL
Jones
Division of Cardiology, Department of Medicine, University of Colorado School of Medicine, 12700 E. 19th Avenue, B139, Aurora, Colorado 80045, USA.
Mark Y
MY
Jeong
Division of Cardiology, Department of Medicine, University of Colorado School of Medicine, 12700 E. 19th Avenue, B139, Aurora, Colorado 80045, USA.
Lori A
LA
Walker
Division of Cardiology, Department of Medicine, University of Colorado School of Medicine, 12700 E. 19th Avenue, B139, Aurora, Colorado 80045, USA.
Peter M
PM
Buttrick
Division of Cardiology, Department of Medicine, University of Colorado School of Medicine, 12700 E. 19th Avenue, B139, Aurora, Colorado 80045, USA.
Timothy A
TA
McKinsey
Division of Cardiology, Department of Medicine, University of Colorado School of Medicine, 12700 E. 19th Avenue, B139, Aurora, Colorado 80045, USA.|Charles C. Gates Center for Regenerative Medicine and Stem Cell Biology, University of Colorado School of Medicine, 12700 E. 19th Avenue, B139, Aurora, Colorado 80045, USA.
Kunhua
K
Song
D000200:Action Potentials; D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics; D015153:Blotting, Western; D065150:Cellular Reprogramming / Q000235:genetics*; D000067470:Cellular Reprogramming Techniques / Q000379:methods*; D047369:Chromatin Immunoprecipitation; D004622:Embryo, Mammalian; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism*; D005355:Fibrosis; D050991:GATA4 Transcription Factor / Q000235:genetics; D007150:Immunohistochemistry; D064326:MEF2 Transcription Factors / Q000235:genetics; D051379:Mice; D035683:MicroRNAs / Q000235:genetics; D032383:Myocytes, Cardiac / Q000166:cytology / Q000378:metabolism*; D060888:Real-Time Polymerase Chain Reaction; D017423:Sequence Analysis, RNA; D015398:Signal Transduction; D020825:T-Box Domain Proteins / Q000235:genetics; D016212:Transforming Growth Factor beta / Q000037:antagonists & inhibitors*; D054460:rho-Associated Kinases / Q000037:antagonists & inhibitors*
D051792:Basic Helix-Loop-Helix Proteins; D050991:GATA4 Transcription Factor; D064326:MEF2 Transcription Factors; D035683:MicroRNAs; D020825:T-Box Domain Proteins; D016212:Transforming Growth Factor beta; D054460:rho-Associated Kinases; C484171:Gata4 protein, mouse; C498766:Hand2 protein, mouse; C578041:Mef2c protein, mouse; C517731:Mirn1 microRNA, mouse; C517732:Mirn133 microRNA, mouse; C103172:T-box transcription factor 5