Development of a Novel, Clinically Relevant Model for Investigating Factors That Stimulate Human Hair Growth

The study aimed to develop a novel model system for investigating human hair growth by focusing on intermediate hair follicles, which are more clinically relevant than the commonly studied terminal scalp follicles. Intermediate follicles, characterized by their smaller size, less pigmentation, and distinct morphology, showed significant differences in growth and gene expression compared to terminal follicles. The research demonstrated that testosterone stimulated growth in intermediate follicles, an effect blocked by the anti-androgen cyproterone acetate but not by finasteride. The presence of androgen receptors and 5α-reductase type 2 proteins was confirmed in both follicle types, with increased gene expression in intermediate follicles. This model provided a promising, though technically challenging, approach for future hair growth studies.