ABSTRACT
Hypoxia and hypoxia-regulated factors [hypoxia-inducible factor-1α (Hif-1α), factor inhibiting Hif-1α (Fih-1)] have essential roles in skin wound healing. Using Foxn1-/- mice that can heal skin injuries in a unique scar-free manner, we investigated the interaction between Foxn1 and hypoxia-regulated factors. Foxn1-/- mice displayed impairments in the regulation of Hif-1α and Fih-1 during the healing process. An analysis of wounded skin showed that the skin of Foxn1-/- mice healed in a scarless manner, displaying rapid re-epithelialization and an increase in Tgfβ-3 and collagen III expression. An in vitro analysis revealed that Foxn1 overexpression in keratinocytes isolated from the skin of Foxn1-/- mice led to reduced Hif-1α expression in normoxic but not hypoxic cultures and inhibited Fih-1 expression exclusively under hypoxic conditions. These data indicate that in the skin, Foxn1 affects hypoxia-regulated factors that control the wound healing process and suggest that under normoxic conditions, Foxn1 is a limiting factor for Hif-1α.
Competing Interest Statement
The authors have declared no competing interest.