Pigmentation of Regenerated Hairs After Wounding

The study from 6 years ago, titled "Pigmentation of regenerated hairs after wounding", aimed to understand the conditions necessary to regenerate pigmented hairs after severe wounding. The researchers observed de novo hair regeneration during the re-epithelialization process after full thickness excision of dorsal skin in mice. They found that pigmented hair regeneration was successful when a wound was created during the anagen stage of the hair cycle. An increase in the number of melanocyte stem cells and Wnt7a expression in the skin was observed, which likely directed these stem cells to produce pigmented hairs in the regenerating follicles. Additionally, transgenic mice expressing the melanocyte stimulatory factor Kitl in their skin promoted the regeneration of pigmented hairs regardless of the hair cycle stage. The study concluded that there is a close regulatory process between keratinocyte stem cells and melanocyte stem cells during de novo hair regeneration after wounding.