Pro-fibrotic signaling potently antagonizes cardiac reprogramming. Inhibition of pro-fibrotic signaling using small molecules that target the transforming growth factor-β/SMAD, or Rho kinase leads to conversion of approximately 60% of fibroblasts into beating cardiomyocytes. Conversely, over-activation of these pro-fibrotic signaling networks inhibits cardiac reprogramming. Using the disclosed methods, fibroblasts are converted to spontaneously contracting cardiomyocytes in less than two weeks.
