iASPP protects the heart from ischemia injury by inhibiting p53 expression and cardiomyocyte apoptosis

Acta Biochim Biophys Sin (Shanghai). 2021 Jan 12;53(1):102-111. doi: 10.1093/abbs/gmaa104.

Abstract

Currently, there remains a great need to elucidate the molecular mechanism of acute myocardial infarction in order to facilitate the development of novel therapy. Inhibitor of apoptosis-stimulating protein of p53 (iASPP) is a member of the ASPP family proteins and an evolutionarily preserved inhibitor of p53 that is involved in many cellular processes, including apoptosis of cancer cells. The purpose of this study was to investigate the possible role of iASPP in acute myocardial infarction. The protein level of iASPP was markedly reduced in the ischemic hearts in vivo and hydrogen peroxide-exposed cardiomyocytes in vitro. Overexpression of iASPP reduced the infarct size and cardiomyocyte apoptosis of mice subjected to 24 h of coronary artery ligation. Echocardiography showed that cardiac function was improved as indicated by the increase in ejection fraction and fractional shortening. In contrast, knockdown of iASPP exacerbated cardiac injury as manifested by impaired cardiac function, increased infarct size, and apoptosis rate. Mechanistically, overexpression of iASPP inhibited, while knockdown of iASPP increased the expressions of p53 and Bax, the key regulators of apoptosis. Taken together, our results suggested that iASPP is an important regulator of cardiomyocyte apoptosis, which represents a potential target in the therapy of myocardial infarction.

Keywords: apoptosis; iASPP; myocardial infarction; p53.

MeSH terms

  • Animals
  • Apoptosis / genetics
  • Disease Models, Animal
  • Down-Regulation
  • Gene Knockdown Techniques
  • Heart Injuries / genetics
  • Heart Injuries / pathology
  • Heart Injuries / prevention & control
  • Hydrogen Peroxide / toxicity
  • Intracellular Signaling Peptides and Proteins / genetics*
  • Intracellular Signaling Peptides and Proteins / metabolism*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Myocardial Ischemia / etiology
  • Myocardial Ischemia / genetics*
  • Myocardial Ischemia / metabolism*
  • Myocytes, Cardiac / drug effects
  • Myocytes, Cardiac / metabolism
  • Primary Cell Culture
  • Repressor Proteins / genetics*
  • Repressor Proteins / metabolism*
  • Tumor Suppressor Protein p53 / antagonists & inhibitors*
  • bcl-2-Associated X Protein / metabolism

Substances

  • Bax protein, mouse
  • Intracellular Signaling Peptides and Proteins
  • Ppp1r13l protein, mouse
  • Repressor Proteins
  • Trp53 protein, mouse
  • Tumor Suppressor Protein p53
  • bcl-2-Associated X Protein
  • Hydrogen Peroxide