Induction of the mitochondrial NDUFA4L2 protein by HIF-1a regulates heart regeneration by promoting the survival of cardiac stem cell

Biochem Biophys Res Commun. 2018 Sep 18;503(4):2226-2233. doi: 10.1016/j.bbrc.2018.06.142. Epub 2018 Jun 28.

Abstract

The adult mammalian heart doesn't regenerate after cardiomyocyte injury, which was mainly caused by the severe and persistent effects of cardiomyopathy. Recently, some studies reported that the mammalian heart can regenerate under low oxygen environment. However, the mechanism that the mammalian heart can regenerate remains unknown. Here, we used cardiac stem cells (CSCs) to be planted in serum-free medium under hypoxia environment to understand the mechanism of HIF1α/NDUFA4L2 in the regulation of hypoxia-alleviated apoptosis. Our results revealed that hypoxia can alleviated CSCs apoptosis. Hypoxia inhibited the level of cleaved-caspase3 and stimulated the expression of stabilized HIF-1α. DMOG promotes the survival of CSCs and the protein expression of NDUFA4L2. 2-ME repressed the survival of CSCs and the protein expression of NDUFA4L2. CHIP assay showed that HIF-1α regulated the survival of CSCs by augmenting the combination of HIF-1α and NDUFA4L2's HRE. Knockdown of NDUFA4L2 reversed the role of hypoxia in the survival of CSCs. Taken together, hypoxia promotes the viability of CSCs in serum-free medium by HIF-1α/NDUFA4L2 signaling pathway.

Keywords: Cardiac stem cell; Cell hypoxia; Hypoxia-inducible factor 1; NDUFA4L2.

MeSH terms

  • Animals
  • Calmodulin-Binding Proteins / genetics*
  • Cell Hypoxia
  • Cell Survival
  • Cells, Cultured
  • Heart / physiology*
  • Humans
  • Hypoxia-Inducible Factor 1, alpha Subunit / physiology*
  • Mitochondrial Proteins / genetics
  • Myocardium / cytology
  • Regeneration*
  • Signal Transduction
  • Stem Cells / cytology
  • Transcriptional Activation

Substances

  • Calmodulin-Binding Proteins
  • Hypoxia-Inducible Factor 1, alpha Subunit
  • Mitochondrial Proteins
  • NDUFAF4 protein, human