In vitro biocompatibility and wound healing properties of latex proteins dressing

Collagen-polyurethane-dextran hydrogels enhance wound healing by inhibiting inflammation and promoting collagen fibrillogenesis

Diabetic foot ulcers are a serious complication of uncontrolled diabetes, emphasizing the need to develop wound healing strategies that are not only effective but also biocompatible, biodegradable, and safe. We aimed to create biomatrices composed of semi-interpenetrated polymer networks of collagen, polyurethane, and dextran, to enhance the wound healing process. The hydrogels were extensively characterized by various analytical techniques, including analysis of their structure, crystallinity, thermal properties, gelation process, reticulation, degradation, cell proliferation, and healing properties, among others. Semi-interpenetrated hydrogels containing dextran at levels of 10%, 20%, and 30% exhibited porous interconnections between collagen fibers and entrapped dextran granules, with a remarkable crosslinking index of up to 94% promoted by hydrogen bonds. These hydrogels showed significant improvements in mechanical properties, swelling, and resistance to proteolytic and hydrolytic degradation. After 24 h, there was a significant increase in the viability of several cell types, including RAW 264.7 cells, human peripheral blood mononuclear cells, and dermal fibroblasts. In addition, these hydrogels demonstrated an increased release of interleukin-10 and transforming growth factor-beta1 while inhibiting the release of monocyte chemotactic protein-1 and tumor necrosis factor-alpha after 72 h. Furthermore, these hydrogels accelerated the wound healing process in diabetic rats after topical application. Notably, the biomaterial with 20% dextran (D20) facilitated wound closure in only 21 days. These results highlight the potential of the D20 hydrogel, which exhibits physicochemical and biological properties that enhance wound healing by inhibiting inflammation and fibrillogenesis while remaining safe for application to the skin.

Investigation of UV-treated mesenchymal stem cells in an in vitro wound model

This study examines the effects of ultraviolet-induced adipose tissue-derived mesenchymal stem cells and their supernatants on wound healing regarding cell viability, percentage of wound healing, released cytokine, and growth factors. It has been reported in previous studies that mesenchymal stem cells are resistant to ultraviolet light and have a protective effect on skin cells against ultraviolet-induced damage. At the same time, there are many studies in the literature about the positive effects of cytokines and growth factors secreted by mesenchymal stem cells. Based on this information, the effects of ultraviolet-induced adipose-derived stem cells and supernatants containing their secreted cytokines and growth factors on an in vitro two-dimensional wound model created with two different cell lines were investigated in this study. It was determined from the results that the highest cell viability and the least apoptotic staining were 100 mJ in mesenchymal stem cells (**p < 0.01). Furthermore, analysis of cytokines and growth factors collected from supernatants also supported 100 mJ as the optimal ultraviolet dose. It was observed that cells treated with ultraviolet and their supernatants significantly increased cell viability and wound-healing rate over time compared to other groups. In conclusion, with this study, it has been shown that adipose-derived stem cells exposed to ultraviolet light can have an important use in wound healing, both with their potential and with the more cytokines and growth factors they secrete. However, further analysis and animal experiments should be performed before clinical use.

Moringa oleifera Leaf Extract Promotes Healing of Infected Wounds in Diabetic Rats: Evidence of Antimicrobial, Antioxidant and Proliferative Properties

Moringa oleifera is known to possess wound healing activity. The present study evaluated the healing properties of methanolic extract of M. oleifera leaves in excision wounds infected with methicillin-resistant Staphylococcus aureus (MRSA) or P. aeruginosa in diabetic rats. An in vitro study was also carried out to determine the gene expression of VEGF and TGF-β1. Preliminary phytochemical and GC-MS analyses were carried out to determine different chemical constituents present in the extract. M. oleifera was applied locally as an ointment at two different concentrations. Wound contraction, period of epithelization, antioxidant enzyme activities and histological changes were determined. For the gene expression study, HaCaT cell lines were used. The formulation of M. oleifera extract improved wound contraction and decreased the period of epithelization, which was associated with an increase in antioxidant enzyme activities, epithelization, capillary density and collagen formation in MRSA-infected diabetic rats. However, this effect was reduced in diabetic animals infected with P. aeruginosa. An increase in the expression of VEGF and TGF-β1 was observed in HaCaT cell lines. M. oleifera extract promotes the healing of infected wounds in MRSA-infected diabetic rats but is less effective in the healing of wounds infected with P. aeruginosa in diabetic rats.