ABSTRACT
Wound repair is critical to avoid pathogen infections and sepsis. Despite advances in the wound-healing field, including the successful application of various tissue-grafting approaches, chronic nonhealing wounds still represent a major clinical challenge. To develop more effective repair strategies and improve the healing outcome, it will be critical to better understand the wound repair processes and examine the underlying mechanisms in the natural environment. This chapter focuses on a conserved molecule that is released from wound keratinocytes following acute injury and which stimulates a variety of tissue repair processes, the small reactive oxygen species (ROS), that is, hydrogen peroxide (H2O2). H2O2 promotes inflammation by recruiting leukocytes to the wound. It also stimulates cutaneous sensory axon regeneration and the migration of wound epidermal keratinocytes to promote wound closure. Recent studies have implicated H2O2 moreover in appendage regeneration in species with high natural repair capacity. We review the major findings related to H2O2 signaling during wound repair and appendage regeneration, highlighting the beneficial functions of this ROS for the wound-healing process. Acknowledging the crucial role of H2O2 during wound repair will be important for the successful integration of grafted tissues and restoration of skin in the future.
