FIGURE 2.

Sensory nerves role in the hair follicle melanocyte stem cell (MeSC) niche. Two main stem cell populations are present in the hair follicle bulge: MeSCs and hair follicle stem cells (HFSCs). MeSCs generate new pigmented hair. Zhang and colleagues revealed that hyperactivation of sympathetic nerves leads to MeSCs activation, proliferation, and consequently elimination from their niche, leading to hair discoloration. ¹²⁶ Interestingly, resinoferatoxin (RTX), which causes sensory nerve denervation as well, was used to induce stress. Adrb2, β2‐adrenergic receptor; NE, norepinephrine