Research Paper Volume 7, Issue 9 pp 718—733
Attenuation of p38α MAPK stress response signaling delays the in vivo aging of skeletal muscle myofibers and progenitor cells
- 1 The Department of Biochemistry and Molecular Biology, The University of Texas Medical Branch, Galveston, TX 77551-06743, USA
- 2 Institute for Research on Cancer and Ageing of Nice, INSERM, U1081-UMR CNRS 7284, University of Nice – Sophia Antipolis, Centre Antoine Lacassagne, Nice, France
Received: July 21, 2015 Accepted: August 28, 2015 Published: September 28, 2015https://doi.org/10.18632/aging.100802
How to Cite
Functional competence and self-renewal of mammalian skeletal muscle myofibers and progenitor cells declines with age. Progression of the muscle aging phenotype involves the decline of juvenile protective factors i.e., proteins whose beneficial functions translate directly to the quality of life, and self-renewal of progenitor cells. These characteristics occur simultaneously with the age-associated increase of p38α stress response signaling. This suggests that the maintenance of low levels of p38α activity of juvenile tissues may delay or attenuate aging. We used the dominant negative haploinsufficient p38α mouse (DN-p38αAF/+) to demonstrate that in vivo attenuation of p38α activity in the gastrocnemius of the aged mutant delays age-associated processes that include: a) the decline of the juvenile protective factors, BubR1, aldehyde dehydrogenase 1A (ALDH1A1), and aldehyde dehydrogenase 2 (ALDH2); b) attenuated expression of p16Ink4a and p19Arf tumor suppressor genes of the Cdkn2a locus; c) decreased levels of hydroxynonenal protein adducts, expression of COX2 and iNOS; d) decline of the senescent progenitor cell pool level and d) the loss of gastrocnemius muscle mass. We propose that elevated P-p38α activity promotes skeletal muscle aging and that the homeostasis of p38α impacts the maintenance of a beneficial healthspan.