Aberrant Connective Tissue Sheath Contraction Drives Premature Hair Follicle Regression by Inducing Progenitor Cell Depletion in Androgenetic Alopecia

The study "Aberrant connective tissue sheath contraction drives premature hair follicle regression by inducing progenitor cell depletion in androgenetic alopecia" reveals that androgenetic alopecia (AGA), a condition characterized by patterned baldness, is caused by the enhanced contraction of the connective tissue sheath (CTS) in hair follicles. This contraction activates the mechanosensitive channel PIEZO1, leading to increased apoptosis (cell death) of progenitor cells in human hair follicles. This continuous contraction and subsequent cell death cause long-term loss of progenitor cells, leading to premature hair regression. The study also found that targeting CTS contraction with ML-7, a selective myosin light chain kinase (MLCK) inhibitor, can significantly improve hair growth in AGA patients. This suggests that the CTS surrounding human hair follicles could be a potential therapeutic target for treating AGA.