Sarcopenia phenotype and impaired muscle function in male mice with fast-twitch muscle-specific knockout of the androgen receptor.

ABSTRACT: Sarcopenia is distinct from normal muscle atrophy in that it is closely related to a shift in the muscle fiber type. Deficiency of the anabolic action of androgen on skeletal muscles is associated with sarcopenia; however, the function of the androgen receptor (AR) pathway in sarcopenia remains poorly understood. We generated a mouse model (fast-twitch muscle-specific AR knockout [fmARKO] mice) in which the AR was selectively deleted in the fast-twitch muscle fibers. In young male mice, the deletion caused no change in muscle mass, but it reduced muscle strength and fatigue resistance and induced a shift in the soleus muscles from fast-twitch fibers to slow-twitch fibers (14% increase, P = 0.02). After middle age, with the control mice, the male fmARKO mice showed much less muscle f

SUBMITTER: Hosoi T 

PROVIDER: S-EPMC9942915 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature