Epiregulin Promotes Hair Growth Via EGFR-Mediated Epidermal and ErbB4-Mediated Dermal Stimulation

The study found that epiregulin (EREG) promoted hair growth by activating EGFR in outer root sheath (ORS) cells and ErbB4 in dermal papilla cells (DPCs). EREG's activation of these receptors led to increased cell proliferation and migration, as well as regulation of reactive oxygen species (ROS) levels through NOX4 expression. EREG was primarily expressed during the anagen phase of hair cycling, and its knockdown inhibited hair growth, while subcutaneous injection promoted the telogen-to-anagen transition in mice. These findings suggested that EREG could be a potential therapeutic target for hair loss treatment.