Oral Presentation The Annual Scientific Meeting of the Endocrine Society of Australia and the Society for Reproductive Biology 2014

Neuronal androgen receptor regulation of muscle mass (#45)

Kesha Rana 1 , Michele V Clarke 1 , Rachel A Davey 1 , Jeffrey D Zajac 1
  1. Department of Medicine, University of Melbourne, Austin Health, Heidelberg, Victoria, Australia
We have previously shown that global deletion of the androgen receptor (AR) in mice results in a 15-22% decrease in hind-limb muscle mass compared to wildtype (WT), while the reduction in muscle mass in mice in which the AR is only deleted in muscle is much lower at 0-6%. These results suggest that there is another major target of androgen action in the regulation of muscle mass. To investigate the role of androgens acting via the AR in neurons on muscle mass and strength, we generated a neuron-specific AR knockout (KO) mouse model, in which exon 3 of the AR gene has been deleted from neurons only by breeding floxed AR mice with CamKII-Cre mice. Preliminary data shows that 6 week old neuron-specific ARKO male mice have a 15% decrease in gastrocnemius muscle mass compared to WT littermates (n≥5 mice/group, p<0.01). Total body mass of neuron-specific ARKO mice is decreased by 8% compared to WT (n≥5 mice/group, p<0.05). These data provide evidence for a role of androgens to increase muscle mass, at least in part, via neurons.