Molecular Approach of Hair Biology

The document discussed the complex interactions within the pilo-sebaceous unit, which includes various cell types and their roles in the hair cycle phases: anagen (growth), catagen (involution), and telogen (resting). While the structure of hair follicles was well understood, the molecular mechanisms controlling these phases were not fully known. Research using in vitro and in vivo models provided insights into the roles of growth factors like IGF-1, TGF alpha, HGF, and EGF, androgens such as 5 alpha-dihydrotestosterone, cytokines like IL-1, and potassium channel openers like minoxidil. The document anticipated future discoveries of additional mediators and emphasized the challenge of understanding how these signals integrate to regulate hair follicle development.