Castration-Induced Pelvic Floor Muscle Specific Atrophy and the Effect of Voluntary Wheel-Running Exercise

Abstract

Purpose: Pelvic floor muscles play an important role in excretion control and thus maintaining their function is crucial to quality of life. The aim of this study was to examine muscle atrophy in a mouse model of androgen deprivation and the effect of voluntary wheel-running exercise on pelvic floor muscles.

Methods: Castration and sham-operation were performed on 3-month-old male mice (C57BL/6J). Castrated mice were randomly housed in cages equipped with a running wheel. After 8 weeks from the operation, muscle samples were collected from limb and perineal (Limb muscles: tibialis anterior, gastrocnemius, extensor digitorum longus, plantaris and soleus. Perineal muscles: bulbospongiosus and levator ani). Myofibers were isolated from extensor digitorum longus and peri-urethral sphincter and the diameters were measured.

Results: Castration significantly decreased perineal muscles' mass and myofiber diameter of periurethral sphincter, whereas limb muscles were not affected. Voluntary wheel-running exercise cannot ameliorate castration-induced muscle atrophy in pelvic floor muscles.

Conclusion: Whole-body exercise cannot prevent pelvic floor muscle loss caused by androgen deprivation and thus it is suggested that target-muscle-specific training needs to be considered for the intervention.