Biology of Human Hair: Know Your Hair to Control It

The document from 2010 provides an extensive examination of human hair biology, detailing the structure, pigmentation, and life cycle of hair, including the newly introduced "kenogen" phase. It emphasizes the role of various signaling pathways and hormones in hair follicle development and cycling, and the impact of these factors on hair growth disorders. The paper discusses current FDA-approved treatments for hair loss, such as minoxidil and finasteride, and the potential for future therapies involving gene modulation through RNA interference. Additionally, it explores the hair follicle as a target for drug delivery and the development of new treatments for hair and skin conditions, including the use of protein disulfide isomerase for hair fiber treatment and the challenges in hair coloring. The document underscores the importance of understanding hair biology for the creation of more effective and less damaging therapeutic approaches, and highlights the promising research in stem cell modulation for treating hair and scalp disorders.