Neurogenic Skin Inflammation in Stress-Triggered Inhibition of Hair Growth in Mice Is Promoted via Nerve Growth Factor-Dependent Pathways

The study explored the role of nerve growth factor (NGF) in stress-triggered hair loss in mice, highlighting the brain-hair follicle axis. Researchers found that stress increased NGF expression, which in turn elevated the release of the neuropeptide substance P (SP). This process led to premature onset of the catagen phase of the hair cycle, apoptosis, and activation of perifollicular mast cells and macrophages. Neutralizing NGF inhibited these stress-induced effects. Additionally, injecting recombinant NGF increased SP-positive neurons, suggesting that stress-induced NGF release promotes neurogenic inflammation, contributing to hair loss.