Leptin of Dermal Adipose Tissue Is Differentially Expressed During the Hair Cycle and Contributes to Adipocyte-Mediated Growth Inhibition of Anagen-Phase Vibrissa Hair

The study investigated the role of leptin, a major adipokine, in hair cycle progression by examining its expression in dermal white adipose tissue. It was found that leptin levels varied throughout the hair cycle, being lowest in the early anagen phase, increasing in the late anagen phase, and peaking in the telogen phase. Leptin receptors were identified in the keratin 15‐positive hair bulge epithelium of both anagen- and telogen-phase hair follicles in mice and human hair. The research demonstrated that leptin contributed to the inhibition of anagen-phase vibrissa hair growth through adipocyte mediation, suggesting that leptin from dermal white adipose tissue could regulate hair growth and cycle progression via its receptor on hair follicle epithelium.