Objective: Recognized as pathogen-associated molecular patterns (PAMPs), β-glucans, a naturally occurring heterogeneous group of polysaccharides, were investigated for their ability to accelerate wound healing in the form of high water-retaining hydrogel dressing. Approach: Full-thickness wounds on the dorsal side of mice created using a 5-mm biopsy punch were treated with β-glucan-based hydrogel for 2 weeks. Standardized photographs of the wound site were taken at regular time intervals to calculate the percentage of wound closure. Tissues isolated from the wound area were subjected to histological examination and immunoblot analysis. Results: β-Glucan-based hydrogel significantly accelerated the duration of wound healing and enhanced the development of skin appendages in the regenerated skin tissue. Increased expression of transforming growth factor-β3 in the skin tissue isolated from the healed wound site indicated that skin regeneration rather than skin repair occurred, thereby minimizing cutaneous scarring. The expression level of cytokeratin 10 and cytokeratin 14 in the isolated skin tissue revealed that the wounds treated with hydrogel showed proper differentiation and proliferation of keratinocytes in the epidermal layer. Innovation: Immunomodulating β-glucan (responsible for fighting infections at the wound site, and enhancing the migration and proliferation of keratinocytes and fibroblasts) in the form of a three-dimensional hydrogel membrane that retains a high water content (responsible for cooling and soothing effect around the wound site, thereby reducing pain) was prepared and analyzed for its effects on the cutaneous wound healing mechanism. Conclusion: β-Glucan-based hydrogels are promising as wet wound dressings in the health care industry.

Keratinocyte-fibroblast interactions are critical for skin repair after injury. During the proliferative phase of wound healing, proliferation, migration and differentiation of these cells are the major mechanisms leading to tissue remodeling. We have previously reported that glycitin, a major soy isoflavone, stimulates dermal fibroblast proliferation; and the phytochemical, 4′,6,7-trimethoxyisoflavone (TMF), induces migration of HaCaT keratinocyte cells. We therefore investigated whether these compounds display synergistic effects on skin cells during wound healing in vitro and in vivo. Co-treatment with TMF and glycitin synergistically promotes the proliferation and migration of both keratinocytes and dermal fibroblasts, with a 1:1 ratio of these compounds showing the greatest efficacy in our co-culture system. This keratinocyte-fibroblast interaction occurred via the secretion of TGF-β, and the induction of differentiation and proliferation was confirmed in both indirect and direct co-culture assays. In an excisional and burn wound animal model, mice treated with a 1:1 ratio of TMF and glycitin showed faster wound closure, regeneration and scar reduction than even the positive control drug. These data indicate that two isoflavones, TMF and glycitin, act synergistically to promote wound healing and anti-scarring and could potentially be developed together as a bioactive therapeutic for wound treatment.

Epithelial-to-mesenchymal transition (EMT) promulgates epithelial cell associated disease-defining characteristics in tumorigenesis and organ fibrosis. Growth factors such as epidermal growth factor and fibroblast growth factor in addition to cytokines such as transforming growth factor-β1 (TGF-β1) is said to play a prominent role in remodeling related pathological events of cancer progression such as invasion, metastasis, apoptosis, EMT, etc. through redox related cellular secondary messengers, in particular the reactive oxygen species (ROS). However, the signaling cascade underlying the redox mechanism and thereby the progression of EMT remains largely unknown. In this study, upon TGF-β1 treatment, we observed an induction in NOX isoforms—NOX2 and NOX4—that have time (early and late) and cellular localization (nucleus and autophagosome co-localized) dependent effects in mediating EMT associated cell proliferation and migration through activation of the focal adhesion kinase (FAK)/SRC pathway in HeLa, human cervical cancer cells. Upon silencing NOX2/4 gene expression and using the SRC inhibitor (AZD0530), progression of TGF-β1 induced EMT related cellular remodeling, extra cellular matrix (ECM) production, cell migration and invasion, got significantly reverted. Together, these results indicate that NOX2 and NOX4 play important, albeit distinct, roles in the activation of cytokine mediated EMT and its associated processes via tyrosine phosphorylation of the FAK/SRC pathway.

Cutaneous wound repair is an intricate process whereby the skin reprograms itself after injury. In the mid-phase of wound repair, the proliferation, migration, and differentiation of cells are the major mechanisms to lead remodeling. We investigated the effect of BMM ((1E,2E)-1,2-bis((6-bromo-2H-chromen-3-yl)methylene)hydrazine), a novel synthetic material, on the migration and viability of keratinocytes or fibroblasts using the in vitro scratch woundhealing, electric cell-substrate imedance sensing (ECIS), invasion, and MTT assays. Cell migration-related factors were analyzed using western blot, and we found that treatment with BMM stimulated the EMT pathway and focal adhesion kinase (FAK)/Src signaling. Differentiation of HaCaT keratinocyte and fibroblast cells was also stimulated by BMM and specifically, NOX2/4 contributed to the activation of fibroblasts for wound healing. Furthermore, BMM treated HaCaT keratinocyte and fibroblast-co-cultured cells increased migration and differentiation. TGF-β and Cyr61 were also secreted to a greater extent than in single cultured cells. In vivo experiments showed that treatment with BMM promotes wound closure by promoting re-epithelialization. In this study, we demonstrated that a novel synthetic material, BMM, is capable of promoting wound healing via the stimulation of re-epithelialization in the epidermis and the activation of fibroblasts in the dermis, in particular, via the acceleration of the interaction between the epidermis and dermis.