Inhibitory effect of p53 upregulated modulator of apoptosis targeting siRNA on hypoxia/reoxygenation-induced cardiomyocyte apoptosis in rats

Cardiology. 2012;122(2):93-100. doi: 10.1159/000338701. Epub 2012 Jun 30.

Abstract

Objectives: The effect of p53 upregulated modulator of apoptosis (PUMA) in hypoxia/reoxygenation-induced cardiomyocyte injuries in rats was investigated.

Methods: PUMA-targeting (si-PUMA) and scramble siRNAs were designed and transfected into primarily rat cardiomyocytes in vitro.

Results: RT-PCR and Western blot analysis showed that 50 nmol/l of si-PUMA can specifically inhibit PUMA expression. MTT assay and lactate dehydrogenase activity detection showed that the cell survival rate in the si-PUMA group was enhanced and that the lactate dehydrogenase enzymatic activity dramatically decreased compared with the control group (p < 0.01). Spectrophotometry, as well as annexin V and propidium iodide staining, combined with flow cytometry, revealed that caspase-3 activity in the si-PUMA group was downregulated and the apoptotic rate was decreased (p < 0.01). RT-PCR also showed that Bax expression was downregulated and Bcl-2 expression was upregulated in the si-PUMA group, compared with the control group (p < 0.05). si-PUMA protects cardiomyocytes from apoptosis.

Conclusion: PUMA mediates hypoxia/reoxygenation-induced cardiomyocyte apoptosis, which can be a potential target of gene therapy for ischemia/reperfusion cardiomyocyte injuries.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Apoptosis / physiology*
  • Apoptosis Regulatory Proteins / metabolism
  • Apoptosis Regulatory Proteins / physiology*
  • Caspase 3 / metabolism
  • Cell Enlargement
  • Cell Hypoxia / physiology
  • Cell Survival
  • Cells, Cultured
  • Down-Regulation
  • Myocytes, Cardiac / enzymology
  • Myocytes, Cardiac / physiology*
  • Proto-Oncogene Proteins c-bcl-2 / metabolism
  • RNA, Small Interfering
  • Rats
  • Reperfusion Injury / physiopathology
  • Transfection
  • bcl-2-Associated X Protein / metabolism

Substances

  • Apoptosis Regulatory Proteins
  • Bax protein, rat
  • Bbc3 protein, rat
  • Proto-Oncogene Proteins c-bcl-2
  • RNA, Small Interfering
  • bcl-2-Associated X Protein
  • Caspase 3