Morphogenesis, Growth Cycle, and Molecular Regulation of Hair Follicles

The document discusses the structure, growth cycle, and molecular regulation of hair follicles, which are crucial for hair growth and skin regeneration. Hair follicles have a high capacity for self-renewal and their growth is influenced by factors such as age, climate, environment, and health status. The hair follicle growth cycle is divided into three stages: anagen, catagen, and telogen, and can be influenced by factors like genetic background, environmental factors, gender, and nutrition. Red light at 650 nm can promote hair follicle cell proliferation and delay the transition from anagen to telogen. Hormones, particularly androgens, and nutrition supply significantly influence the hair growth cycle. Various molecular signaling pathways, such as the WNT, BMP, and EDAR, play significant roles in hair follicle development and cycling. The Shh signaling pathway is crucial for hair follicle development and hair growth, and disruption of Shh activity leads to hair follicle destruction and hair loss. miRNAs like miR-24 and miR-22 regulate hair follicle development and cyclical changes. Understanding these molecules and pathways can provide new ideas for treating hair follicle-related diseases like alopecia areata, but the key activators that promote the transformation of hair follicle stages and the molecular mechanism of hair growth promotion are still unclear.