Molecular hydrogen promotes wound healing by inducing early extracellular matrix deposition and epidermal stem cell proliferation

Abstract

Background Despite progress in developing wound care strategies, there is currently no treatment that promotes the self-tissue repair capabilities. H2 has been shown to effectively protect cells and tissues from oxidative and inflammatory damage. While comprehensive effects and how H2 functions in wound healing are still obscure. Methods Here, we established a cutaneous aseptic wound model and applied a high concentration of H2 (66% H2) in a treatment chamber. Molecular mechanisms and the effects of healing were evaluated by gene functional enrichment analysis, blood perfusion/oxygen detection assay, in vitro tube formation assay, enzyme-linked immunosorbent assay, immunofluorescent staining, non-targeted metabonomic analysis, flow cytometry, transmission electron microscope, and live-cell imaging. Results We revealed that a high concentration of H2 (66% H2) greatly increased the healing rate (3 times higher than the control group) on day 11 post wounding. The effect was not dependent on O2 or anti-reactive oxygen species functions. Histological and cellular experiments proved the fast re-epithelialization in the H2 group. Extracellular matrix components early (3 days post wounding) deposition were found in the H2 group of the proximal wound, especially for the dermal col-I, epidermal col-III, and dermis-epidermis-junction col-XVII. H2 accelerated early autologous epidermal stem cell proliferation (1–2 days in advance) and then differentiation into myoepithelial cells. Other beneficial outcomes include sustained moist healing, greater vascularization, less T-helper-1 and T-helper-17 cell-related systemic inflammation, and better tissue remodelling. Conclusion We have discovered a novel pattern of wound healing induced by molecular hydrogen treatment. These H2-induced multiple advantages in healing may be related to the enhancement of cell viability in various cells and the maintenance of mitochondrial functions at a basic level in the biological processes of life.