A new star on the H2O2rizon of wound healing?

A breakthrough finding has shown that hydrogen peroxide (H(2)O(2)) gradients contribute to recruit leucocytes to the wound site during the inflammatory phase of healing. It was in 1992 that NO was awarded 'molecule of the year' because of the discovery that such a tiny chemical may act as an important signalling molecule, thereby influencing research over decades. We speculate that H(2)O(2) also has the potential to have a broad impact on research over years, especially in mammalian wound healing. To justify our hypothesis, we provide evidence from the literature on (i) how H(2)O(2) gradients are created, (ii) how H(2)O(2) acts in the physiological phases of wound healing and (iii) a possible role of H(2)O(2) in bacterial defense - bacterial colonization being one of the major problems in chronic wounds. Based on this, we provide the first overview on how H(2)O(2) acts during the different wound healing phases.