The poor healing of diabetic wounds is characterized by prolonged inflammation and decreased collagen deposition. Diabetic patients exhibit changes in the plasma concentrations of pro-inflammatory cytokines, and the role of specific dressings may have an impact on healing. This study aims to evaluate the effects of a combined treatment comprising a bacterial cellulose dressing and melatonin application on the regulation and expression of inflammatory cytokines, VEGF, PCNA, and collagen in the healing of cutaneous wounds of diabetic rats. Pro-inflammatory cytokines, including IL-6, TNF-α, and VEGF, along with PCNA and type I and III collagen, were evaluated after 14 days. Immunohistochemistry showed decreased levels of IL-6, TNF-α, and VEGF, along with an increased expression of PCNA and type I collagen, in the groups treated exclusively with melatonin and bacterial cellulose associated with melatonin compared to the control and the commercial healing agent. It was concluded that treating the skin lesions of diabetic animals supplemented with melatonin using a bacterial cellulose-based dressing has positive effects in regulating the expression of inflammatory cytokines, vascular endothelial growth factor, and collagen, showing that this association could be a viable therapy approach in wound healing.

Background: Tissue healing consists of four main phases: coagulation, inflammation, proliferation, and remodeling. In diabetic patients, this process is stagnant in the inflammatory stage, leading to chronic wounds. The aim of this study is to evaluate in an animal model the biological evidence related to the use of the Rigenera^® technology (Turin Italy), an innovative mechanical procedure to isolate autologous micrografts (AMG). Methods: Fifty male Wistar rats were divided into four groups: control (C), control treated with micrografts (CM), diabetic (DB), and diabetic treated with micrografts (DBM). The experimental setup involved: the quantification of the total collagen and elastic fibers; histopathological analysis; immunohistochemical analysis for collagen type I (COL1), collagen type III (COL3), vascular endothelial growth factor (VEGF-A), and interleukin 4 (IL4) and 10 (IL10); evaluation of the oxidative stress; measurement of gluthatione (GSH); and, finally, an enzyme-linked immunosorbent assay (ELISA) on tumor necrosis factor-α (TNF-α). Results: The AMG technology induces a faster healing process: VEGF-A, IL4, IL10, and GSH increased, while TNF-α and oxidative stress decreased. Conclusions: Animals treated with micrografts showed more favorable results for healing compared to those that did not receive treatment, demonstrating a positive participation of the micrografts in the treatment of difficult-to-heal wounds.

A hydrogel of bacterial cellulose of 0.8%, biopolymer produced from sugarcane molasses and synthesized from a bacteria called Zoogloea sp., was analyzed for its composition and tested by two routes of administration, subcutaneous and intraperitoneal, to clarify the local and systemic adverse effects after skin implantation in Wistar rats (24 males, 24 females, 55 days old). Analysis of two samples of BC films indicates carbon (42.94%; 43.43%), hydrogen (6.73%; 6.76%), nitrogen (0.28%, 0.23%) and oxygen (50.05%, 49.58%). No abnormal behavior, clinical signs of chronic toxicity or inflammation were observed. There was no change in liver injury biomarker levels (ALT, AST and ALP), as well as in renal histology, where it was evaluated to signs of tubular cell injury, glomerular or vascular damage, and renal morphometry, in which it was quantified the number of renal corpuscles, the number of cells per glomerulus and the capsular space area. Thus, the absence of signs and symptoms of toxicity suggests that subcutaneous or intraperitoneal injections of these polymers may be used in clinical situations.