Nrf2 activation supports cell survival during hypoxia and hypoxia/reoxygenation in cardiomyoblasts; the roles of reactive oxygen and nitrogen species

Rajitha T. Kolamunne, Irundika H.K. Dias, Ann B. Vernallis, Melissa M. Grant, Helen R. Griffiths

Research output: Contribution to journalArticle

Abstract

Adaptive mechanisms involving upregulation of cytoprotective genes under the control of transcription factors such as Nrf2 exist to protect cells from permanent damage and dysfunction under stress conditions. Here we explore of the hypothesis that Nrf2 activation by reactive oxygen and nitrogen species modulates cytotoxicity during hypoxia (H) with and without reoxygenation (H/R) in H9C2 cardiomyoblasts. Using MnTBap as a cell permeable superoxide dismutase (SOD) mimetic and peroxynitrite scavenger and L-NAME as an inhibitor of nitric oxide synthase (NOS), we have shown that MnTBap inhibited the cytotoxic effects of hypoxic stress with and without reoxygenation. However, L-NAME only afforded protection during H. Under reoxygenation, conditions, cytotoxicity was increased by the presence of L-NAME. Nrf2 activation was inhibited independently by MnTBap and L-NAME under H and H/R. The increased cytotoxicity and inhibition of Nrf2 activation by the presence of L-NAME during reoxygenation suggests that NOS activity plays an important role in cell survival at least in part via Nrf2-independent pathways. In contrast, O2 -• scavenging by MnTBap prevented both toxicity and Nrf2 activation during H and H/R implying that toxicity is largely dependent on O2 -.To confirm the importance of Nrf2 for myoblast metabolism, Nrf2 knockdown with siRNA reduced cell survival by 50% during 4h hypoxia with and without 2h of reoxygenation and although cellular glutathione (GSH) was depleted during H and H/R, GSH loss was not exacerbated by Nrf2 knockdown. These data support distinctive roles for ROS and RNS during H and H/R for Nrf2 induction which are important for survival independently of GSH salvage. © 2013 The Authors.

Original languageEnglish
Pages (from-to)418-426
Number of pages9
JournalRedox biology
Volume1
Issue number1
DOIs
Publication statusPublished - 2013

Fingerprint

Reactive Nitrogen Species
NG-Nitroarginine Methyl Ester
Reactive Oxygen Species
Cell Survival
Chemical activation
Cells
Cytotoxicity
Nitric Oxide Synthase
Toxicity
Salvaging
Peroxynitrous Acid
Myoblasts
Scavenging
Metabolism
Small Interfering RNA
Superoxide Dismutase
Glutathione
Transcription Factors
Up-Regulation
Genes

Bibliographical note

This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivativeWorksLicense, which permits non-commercial use, distribution, and reproduction in any medium, provided the original author and source are credited.

Keywords

  • adaptive
  • glutathione
  • L-NAME
  • MnTBap
  • RNS
  • ROS

Cite this

@article{4483ca1d514944d886d3ab598c6a0716,
title = "Nrf2 activation supports cell survival during hypoxia and hypoxia/reoxygenation in cardiomyoblasts; the roles of reactive oxygen and nitrogen species",
abstract = "Adaptive mechanisms involving upregulation of cytoprotective genes under the control of transcription factors such as Nrf2 exist to protect cells from permanent damage and dysfunction under stress conditions. Here we explore of the hypothesis that Nrf2 activation by reactive oxygen and nitrogen species modulates cytotoxicity during hypoxia (H) with and without reoxygenation (H/R) in H9C2 cardiomyoblasts. Using MnTBap as a cell permeable superoxide dismutase (SOD) mimetic and peroxynitrite scavenger and L-NAME as an inhibitor of nitric oxide synthase (NOS), we have shown that MnTBap inhibited the cytotoxic effects of hypoxic stress with and without reoxygenation. However, L-NAME only afforded protection during H. Under reoxygenation, conditions, cytotoxicity was increased by the presence of L-NAME. Nrf2 activation was inhibited independently by MnTBap and L-NAME under H and H/R. The increased cytotoxicity and inhibition of Nrf2 activation by the presence of L-NAME during reoxygenation suggests that NOS activity plays an important role in cell survival at least in part via Nrf2-independent pathways. In contrast, O2 -• scavenging by MnTBap prevented both toxicity and Nrf2 activation during H and H/R implying that toxicity is largely dependent on O2 -.To confirm the importance of Nrf2 for myoblast metabolism, Nrf2 knockdown with siRNA reduced cell survival by 50{\%} during 4h hypoxia with and without 2h of reoxygenation and although cellular glutathione (GSH) was depleted during H and H/R, GSH loss was not exacerbated by Nrf2 knockdown. These data support distinctive roles for ROS and RNS during H and H/R for Nrf2 induction which are important for survival independently of GSH salvage. {\circledC} 2013 The Authors.",
keywords = "adaptive, glutathione, L-NAME, MnTBap, RNS, ROS",
author = "Kolamunne, {Rajitha T.} and Dias, {Irundika H.K.} and Vernallis, {Ann B.} and Grant, {Melissa M.} and Griffiths, {Helen R.}",
note = "This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivativeWorksLicense, which permits non-commercial use, distribution, and reproduction in any medium, provided the original author and source are credited.",
year = "2013",
doi = "10.1016/j.redox.2013.08.002",
language = "English",
volume = "1",
pages = "418--426",
journal = "Redox biology",
issn = "2213-2317",
publisher = "Elsevier",
number = "1",

}

Nrf2 activation supports cell survival during hypoxia and hypoxia/reoxygenation in cardiomyoblasts; the roles of reactive oxygen and nitrogen species. / Kolamunne, Rajitha T.; Dias, Irundika H.K.; Vernallis, Ann B.; Grant, Melissa M.; Griffiths, Helen R.

In: Redox biology, Vol. 1, No. 1, 2013, p. 418-426.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Nrf2 activation supports cell survival during hypoxia and hypoxia/reoxygenation in cardiomyoblasts; the roles of reactive oxygen and nitrogen species

AU - Kolamunne, Rajitha T.

AU - Dias, Irundika H.K.

AU - Vernallis, Ann B.

AU - Grant, Melissa M.

AU - Griffiths, Helen R.

N1 - This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivativeWorksLicense, which permits non-commercial use, distribution, and reproduction in any medium, provided the original author and source are credited.

PY - 2013

Y1 - 2013

N2 - Adaptive mechanisms involving upregulation of cytoprotective genes under the control of transcription factors such as Nrf2 exist to protect cells from permanent damage and dysfunction under stress conditions. Here we explore of the hypothesis that Nrf2 activation by reactive oxygen and nitrogen species modulates cytotoxicity during hypoxia (H) with and without reoxygenation (H/R) in H9C2 cardiomyoblasts. Using MnTBap as a cell permeable superoxide dismutase (SOD) mimetic and peroxynitrite scavenger and L-NAME as an inhibitor of nitric oxide synthase (NOS), we have shown that MnTBap inhibited the cytotoxic effects of hypoxic stress with and without reoxygenation. However, L-NAME only afforded protection during H. Under reoxygenation, conditions, cytotoxicity was increased by the presence of L-NAME. Nrf2 activation was inhibited independently by MnTBap and L-NAME under H and H/R. The increased cytotoxicity and inhibition of Nrf2 activation by the presence of L-NAME during reoxygenation suggests that NOS activity plays an important role in cell survival at least in part via Nrf2-independent pathways. In contrast, O2 -• scavenging by MnTBap prevented both toxicity and Nrf2 activation during H and H/R implying that toxicity is largely dependent on O2 -.To confirm the importance of Nrf2 for myoblast metabolism, Nrf2 knockdown with siRNA reduced cell survival by 50% during 4h hypoxia with and without 2h of reoxygenation and although cellular glutathione (GSH) was depleted during H and H/R, GSH loss was not exacerbated by Nrf2 knockdown. These data support distinctive roles for ROS and RNS during H and H/R for Nrf2 induction which are important for survival independently of GSH salvage. © 2013 The Authors.

AB - Adaptive mechanisms involving upregulation of cytoprotective genes under the control of transcription factors such as Nrf2 exist to protect cells from permanent damage and dysfunction under stress conditions. Here we explore of the hypothesis that Nrf2 activation by reactive oxygen and nitrogen species modulates cytotoxicity during hypoxia (H) with and without reoxygenation (H/R) in H9C2 cardiomyoblasts. Using MnTBap as a cell permeable superoxide dismutase (SOD) mimetic and peroxynitrite scavenger and L-NAME as an inhibitor of nitric oxide synthase (NOS), we have shown that MnTBap inhibited the cytotoxic effects of hypoxic stress with and without reoxygenation. However, L-NAME only afforded protection during H. Under reoxygenation, conditions, cytotoxicity was increased by the presence of L-NAME. Nrf2 activation was inhibited independently by MnTBap and L-NAME under H and H/R. The increased cytotoxicity and inhibition of Nrf2 activation by the presence of L-NAME during reoxygenation suggests that NOS activity plays an important role in cell survival at least in part via Nrf2-independent pathways. In contrast, O2 -• scavenging by MnTBap prevented both toxicity and Nrf2 activation during H and H/R implying that toxicity is largely dependent on O2 -.To confirm the importance of Nrf2 for myoblast metabolism, Nrf2 knockdown with siRNA reduced cell survival by 50% during 4h hypoxia with and without 2h of reoxygenation and although cellular glutathione (GSH) was depleted during H and H/R, GSH loss was not exacerbated by Nrf2 knockdown. These data support distinctive roles for ROS and RNS during H and H/R for Nrf2 induction which are important for survival independently of GSH salvage. © 2013 The Authors.

KW - adaptive

KW - glutathione

KW - L-NAME

KW - MnTBap

KW - RNS

KW - ROS

UR - http://www.scopus.com/inward/record.url?scp=84883776707&partnerID=8YFLogxK

U2 - 10.1016/j.redox.2013.08.002

DO - 10.1016/j.redox.2013.08.002

M3 - Article

VL - 1

SP - 418

EP - 426

JO - Redox biology

JF - Redox biology

SN - 2213-2317

IS - 1

ER -