Glutamic acid promotes hair growth in mice.

Glutamic acid is the main excitatory neurotransmitter acting both in the brain and in peripheral tissues. Abnormal distribution of glutamic acid receptors occurs in skin hyperproliferative conditions such as psoriasis and skin regeneration; however, the biological function of glutamic acid in the skin remains unclear. Using ex vivo, in vivo and in silico approaches, we showed that exogenous glutamic acid promotes hair growth and keratinocyte proliferation.