Differential effects of vitamin C or protandim on skeletal muscle adaptation to exercise
Abstract
Maintaining proteostasis is a key mechanism for preserving cell function. Exercise-stimulated proteostasis is regulated, in part, by redox-sensitive signaling. Several studies suggest that supplementation with exogenous antioxidants blunts exercise-induced cellular adaptations, although this conclusion lacks consensus. Our group uses a fundamentally different approach to maintain redox balance by treatment with bioactive phytochemicals to activate the transcription factor nuclear factor (erythroid-derived 2)-like 2 and downstream endogenous antioxidant pathways. We hypothesized that vitamin C (VitC) would interfere with redox-sensitive proteostatic mechanisms in skeletal muscle, whereas phytochemical treatment would permit proteostatic maintenance. We measured protein and DNA synthesis in skeletal muscle from high-volume voluntary wheel-running rats. Whereas phytochemical treatment permitted mitochondrial and other proteostatic adaptations to exercise, VitC treatment did not. During an in vitro oxidative challenge, phytochemical treatment helped maintain proteostasis, including the mitochondrial fraction while VitC did not. Our findings support the conclusion that VitC can blunt some of the beneficial adaptations to exercise. We propose that regulation of endogenous antioxidants represents a novel approach to maintain redox balance while still permitting redox-sensitive proteostatic adaptations.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Aug 01, 2018
- Source ID
- 10.1152/japplphysiol.00277.2018
Entities
People
- Benjamin F. Miller
- Danielle R. Bruns
- Frederick F. Peelor Iii
- Karyn L. Hamilton
- Laurie M. Biela
- Sarah E. Ehrlicher
- Shadi Khademi
Organizations
- Colorado State University
- Defense Advanced Research Projects Agency
- National Institute on Aging