Sex hormones control muscle stem cells

Quiescent adult muscle stem cells (MuSCs) regenerate skeletal muscle upon injury throughout life. However, aged skeletal muscles fail to maintain stem cell quiescence, leading to declines in MuSC number and functionality. Although autophagy plays an important role in the maintenance of MuSC quiescence, how quiescent MuSCs and their autophagy levels are maintained throughout life is largely unknown. The current study reveals how GnRH, a hypothalamic hormone, maintains the quiescence of adult MuSCs by preventing the onset of senescence and how the decline of sex steroids in organismal ageing is implicated in MuSC ageing. Gene expression profiling of WT and Pax7-CreER;Arf/y;Esr2–/– conditional knock out MuSCs.