Mammalian target of rapamycin complex 1 (mTORC1) may modulate the timing of anagen entry in mouse hair follicles

The study investigated the role of the mammalian target of rapamycin complex 1 (mTORC1) in regulating the hair growth cycle in mice. The researchers used biochemical, immunohistochemical, and functional approaches to analyze mTORC1 kinase activity and its localization in hair follicles (HFs) during different growth phases. They found that mTORC1 activity and the presence of phosphorylated mTOR at S2448 varied with the hair cycle phases, suggesting mTOR's involvement in initiating hair growth. Furthermore, the use of rapamycin, a specific mTORC1 inhibitor, delayed the start of the hair growth phase (anagen), indicating mTORC1's functional importance in the timing of anagen entry. The study concluded that mTORC1 likely plays a role in the regulation of the hair cycle, particularly in the timing of anagen initiation.