Corticosterone Inhibits GAS6 to Govern Hair Follicle Stem-Cell Quiescence

In a study from March 31, 2021, researchers found that the stress hormone corticosterone, which is the rodent equivalent of cortisol in humans, plays a significant role in regulating hair follicle stem cell (HFSC) activity and hair growth in mice. The absence of corticosterone led to an increase in HFSC regeneration cycles, while chronic stress and elevated corticosterone levels caused prolonged HFSC quiescence and an extended resting phase for hair follicles. The hormone achieves this by suppressing the expression of Gas6, a gene responsible for producing growth arrest specific 6, a factor that promotes HFSC activation. When Gas6 expression was restored, it counteracted the stress-induced inhibition of HFSC activation and hair growth. This study highlights corticosterone as a key systemic inhibitor of HFSC activity, affecting the hair follicle niche and suggesting that managing stress or manipulating Gas6 expression could potentially be targeted for hair growth therapies.