Disruptions to the Limb Muscle Core Molecular Clock Coincide with Changes in Mitochondrial Quality Control following Androgen Depletion.

Disruptions to the Limb Muscle Core Molecular Clock Coincide with Changes in Mitochondrial Quality Control following Androgen Depletion. Am J Physiol Endocrinol Metab. 2019 Jul 30;: Authors: Rossetti ML, Esser KA, Lee C, Tomko RJ, Eroshkin AM, Gordon BS Abstract Androgen depletion in humans leads to significant atrophy of the limb muscles. However, the pathways by which androgens regulate limb muscle mass are unclear. Our laboratory previously showed that mitochondrial degradation was related to the induction of autophagy and the degree of muscle atrophy following androgen depletion, implying decreased mitochondrial quality contributes to muscle atrophy. To increase our understanding of androgen-sensitive pathways regulating decreased mitochondrial quality, total RNA from the tibialis anterior of sham and castrated mice was subjected to microarray analysis. Using this unbiased approach, we identified significant changes in the expression of genes that comprise the core molecular clock. To assess the extent in which androgen depletion altered the limb muscle clock, the tibialis anterior muscles from sham and castrated mice were harvested every 4 hr throughout a diurnal cycle. The circadian expression patterns of various core clock genes and known clock-controlled genes were disrupted by castration, with most genes exhibiting an overall reduction in phase amplitude. Given that the core clock regulates mitochondrial quality, disruption ...
Source: Am J Physiol Endocri... - Category: Endocrinology Authors: Tags: Am J Physiol Endocrinol Metab Source Type: research