1. Mitochondrial aberrations during the progression of disuse atrophy differentially affect male and female mice
- Author
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Tyrone A. Washington, Megan E. Rosa-Caldwell, Kirsten R. Dunlap, Wesley S. Haynie, Seongkyun Lim, David E. Lee, Nicholas P. Greene, Lisa T. Jansen, Jacob L. Brown, and Michael P. Wiggs
- Subjects
Male ,medicine.medical_specialty ,Mitochondrial translation ,Hindlimb ,Diseases of the musculoskeletal system ,Mitochondrion ,medicine.disease_cause ,Mice ,Atrophy ,Physiology (medical) ,Internal medicine ,Mitophagy ,Sex differences ,medicine ,Autophagy ,Animals ,Orthopedics and Sports Medicine ,Soleus muscle ,business.industry ,QM1-695 ,Catabolism ,Original Articles ,medicine.disease ,Muscle atrophy ,Muscular Disorders, Atrophic ,Mitochondria ,Mice, Inbred C57BL ,Muscular Atrophy ,Endocrinology ,Hindlimb Suspension ,RC925-935 ,Human anatomy ,Muscle ,Female ,Original Article ,medicine.symptom ,business ,Oxidative stress - Abstract
Background Disuse decreases muscle size and is predictive of mortality across multiple pathologies. Detriments to mitochondrial function are hypothesized to underlie disuse‐induced muscle atrophy. Little data exist on early mechanisms contributing to onset of these pathologies, nor is it known how they differ between sexes. The purpose of this study was to examine differential and conserved responses to mitochondrial quality control in male and female mice during the development and progression of disuse‐induced atrophy. Methods One hundred C57BL/6J mice (50 male and 50 female) were hindlimb unloaded to induce disuse atrophy for 0 (con), 24, 48, 72, or 168 h. At designated time‐points, extensor digitorum longus, gastrocnemius, and soleus muscles were collected for analysis of mitochondrial quality control markers. Results One hundred sixty‐eight hours of disuse resulted in ~25% lower oxidative muscle fibre CSA in both male (P = 0.003) and female (P = 0.02) mice without any differences due to disuse in glycolytic fibres. In male mice, 48 h of unloading was sufficient to result in ~67% greater mitochondrial oxidative stress as assessed by the reporter gene pMitoTimer compared with 0 h (P = 0.002), this mitochondrial stress preceded detectable muscle loss. However in female mice, mitochondrial oxidative stress did not occur until 168 h of disuse (~40% greater mitochondrial oxidative stress in 168 h compared with 0 h of disuse, P
- Published
- 2021