[Impact of mesenchymal stem cells transplantation on myocardial myocardin-related transcription factor-A and bcl-2 expression in rats with experimental myocardial infarction]

Zhonghua Xin Xue Guan Bing Za Zhi. 2015 Jun;43(6):531-6.
[Article in Chinese]

Abstract

Objective: To observe the impact of mesenchymal stem cells (BMSCs) transplantation on myocardial myocardin-related transcription factor-A (MRTF-A) and bcl-2 expression in rats with experimental myocardial infarction (MI).

Methods: Thirty rats were randomly divided into sham, MI and MI + BMSCs (1 × 10(6) injected into 4 infarct points immediately post coronary artery ligation) groups (n = 10 each).One week later, TUNEL was used to detect cardiomyocyte apoptosis, the myocardial expression of MRTF-A and bcl-2 was detected by laser scanning confocal microscope and Western blot. In vitro plasmid of MRTF-A and co-transfection with plasmids of MRTF-A and bcl-2 or mutated bcl-2 transfection into cardiomyocyte was applied to evaluate the relationship between MRTF-A and bcl-2.

Results: The number of apoptotic cardiomyocytes in the sham group, MI group and MI + BMSCs group were (4.05 ± 1.56)%, (62.38 ± 8.41)% and (22.36 ± 6.17)%, respectively (P < 0.05). The protein expression of MRTF-A and bcl-2 in the MI group were significantly lower than those in sham group, while significantly upregulated in MI + BMSCs group (P < 0.05 vs. MI). In cultured neonatal rat cardiomyocyte, the expression of bcl-2 protein was significantly upregulated after transfection with MRTF-A plasmid, and bcl-2-luciferase activity significantly increased after co-transfection with plasmids of MRTF-A and bcl-2-luciferase, however, the positive regulatory effect of MRTF-A was abolished after transfection with mutated bcl-2.

Conclusion: Mesenchymal stem cells transplantation can effectively reduce cardiomyocyte apoptosis in this rat MI model, and upregulate the expression of MRTF-A. Consequent up-regulated bcl-2 expression might be involved in the beneficial effects of BMSCs transplantation in this model.

MeSH terms

  • Animals
  • Apoptosis
  • Heart
  • Mesenchymal Stem Cell Transplantation*
  • Mesenchymal Stem Cells
  • Myocardial Infarction*
  • Myocardium
  • Myocytes, Cardiac
  • Nuclear Proteins
  • Proto-Oncogene Proteins c-bcl-2
  • Rats
  • Rats, Sprague-Dawley
  • Trans-Activators
  • Transcription Factors
  • Transfection

Substances

  • Mrtfa protein, rat
  • Nuclear Proteins
  • Proto-Oncogene Proteins c-bcl-2
  • Trans-Activators
  • Transcription Factors
  • myocardin