Clock Genes, Hair Growth, and Aging

The document discussed the role of circadian clock genes, such as CLOCK and BMAL1, in regulating hair follicle cycling and hair growth. It highlighted that these genes are crucial for the timely transition from the telogen to anagen phase by influencing cell cycle progression in the secondary hair germ. Disruptions in these genes, as observed in Bmal1 mutant mice, led to delayed hair growth cycles and upregulation of p21, which slowed G1-S cell cycle progression. The study suggested that circadian clock genes might contribute to aging-related alopecia and hair graying through mechanisms involving oxidative stress, DNA damage, and disruptions in circadian rhythms. Understanding these processes could help develop treatments for hair loss and aging-related hair changes.