New Complex Mechanisms in Hair Growth Regulation: Focus on Outer Root Sheath Keratinocytes

The document explored the complex mechanisms regulating hair growth, focusing on the role of outer root sheath keratinocytes. It highlighted the beneficial effects of adenosine, a locally produced mediator, on hair growth, such as increasing hair diameter and length. Despite some understanding of adenosine's modulatory effects on the hair cycle, many questions remained about its precise impact and regulation. Additionally, caffeine, a widely known alkaloid, was noted for its positive effect on hair growth by inducing the transition of hair follicles from the telogen to the anagen phase, particularly in cases of male-pattern hair loss. The study aimed to gain deeper insights into the regulatory effects of adenosine and caffeine on the hair cycle using human hair follicles and outer root sheath keratinocytes.