Myocardial NADPH oxidase-4 regulates the physiological response to acute exercise
- NIHR Biomedical Research Centre and British Heart Foundation Centre of Excellence School of Cardiovascular Medicine and Sciences St Thomas’ Campus King's College London London United Kingdom
- University of Tromsø - The Arctic University of Norway
- University of Cambridge
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm SE-171 77, Sweden.; Research Center of Neurology, 125367 Moscow, Russia.
- Institut für Kardiovaskuläre Physiologien, Goethe-Universität, Frankfurt, Germany
Research output: Contribution to journal › Article › peer-review
37 Citations (Scopus)
Regular exercise has widespread health benefits. Fundamental to these beneficial effects is the ability of the heart to intermittently and substantially increase its performance without incurring damage, but the underlying homeostatic mechanisms are unclear. We identify the ROS-generating NADPH oxidase-4 (Nox4) as an essential regulator of exercise performance in mice. Myocardial Nox4 levels increase during acute exercise and trigger activation of the transcription factor Nrf2, with the induction of multiple endogenous antioxidants. Cardiomyocyte-specific Nox4-deficient (csNox4KO) mice display a loss of exercise-induced Nrf2 activation, cardiac oxidative stress and reduced exercise performance. Cardiomyocyte-specific Nrf2-deficient (csNrf2KO) mice exhibit similar compromised exercise capacity, with mitochondrial and cardiac dysfunction. Supplementation with an Nrf2 activator or a mitochondria-targeted antioxidant effectively restores cardiac performance and exercise capacity in csNox4KO and csNrf2KO mice respectively. The Nox4/Nrf2 axis therefore drives a hormetic response that is required for optimal cardiac mitochondrial and contractile function during physiological exercise.