Nε-(Carboxymethyl) Lysine Represses Hair Follicle Formation by Inhibiting Sonic Hedgehog Expression in a NF-κB-Independent Manner

The study explored the impact of Nε-(carboxymethyl) lysine (CML) on hair follicle formation and hair growth, revealing that CML weakened hair follicle formation and inhibited hair shaft growth in mice by suppressing Sonic hedgehog (Shh) expression through a RAGE-mediated, NF-κB-independent pathway. This suppression led to hair growth defects, including thinning hair shafts and miniaturized hair bulbs, without affecting apoptosis. CML also inhibited the migration and proliferation of dermal papilla cells, suggesting that CML accumulation could delay hair follicle formation by affecting both epithelial and mesenchymal cell proliferation. These findings provided insights into the mechanisms of hair growth inhibition related to oxidative stress and protein damage, highlighting potential therapeutic targets for hair loss associated with aging and glycation.