Format

Send to

Choose Destination
See comment in PubMed Commons below
Antioxid Redox Signal. 2009 Mar;11(3):589-600. doi: 10.1089/ARS.2008.2195.

Inhibition of ref-1 stimulates the production of reactive oxygen species and induces differentiation in adult cardiac stem cells.

Author information

1
Cardiovascular Research Center, University of Connecticut School of Medicine, Farmington, Connecticut 06030-1110, USA.

Abstract

Redox effector protein-1 (Ref-1) plays an essential role in DNA repair and redox regulation of several transcription factors. In the present study, we examined the role of Ref-1 in maintaining the redox status and survivability of adult cardiac stem cells challenged with a subtoxic level of H2O2 under inhibition of Ref-1 by RNA interference. Treatment of cardiac stem cells with a low concentration of H2O2 induced Ref-1-mediated survival signaling through phosphorylation of Akt. However, Ref-1 inhibition followed by H2O2 treatment extensively induced the level of intracellular reactive oxygen species (ROS) through activation of the components of NADPH oxidase, like p22( phox ), p47( phox ), and Nox4. Cardiac differentiation markers (Nkx2.5, MEF2C, and GATA4), and cell death by apoptosis were significantly elevated in Ref-1 siRNA followed by H2O2-treated stem cells. Further, inhibition of Ref-1 increased the level of p53 but decreased the phosphorylation of Akt, a molecule involved in survival signaling. Treatment with ROS scavenger N-acetyl-L-cysteine attenuated Ref-1 siRNA-mediated activation of NADPH oxidase and cardiac differentiation. Taken together, these results indicate that Ref-1 plays an important role in maintaining the redox status of cardiac stem cells and protects them from oxidative injury-mediated cell death and differentiation.

PMID:
18717627
PMCID:
PMC2933566
DOI:
10.1089/ars.2008.2195
[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Mary Ann Liebert, Inc. Icon for PubMed Central
    Loading ...
    Support Center