To Investigate the Underlying Mechanism of MEBO in Facilitating the Healing of Chronic Refractory Wounds Via the Ferroptosis-related P53/SLC7A11/GPX4 Signaling Pathway

Abstract

Objective: To investigate the effects and underlying mechanisms of moist exposed burn ointment (MEBO) on chronic refractory wounds. Methods: Eighty specific pathogen-free (SPF) healthy male Sprague-Dawley rats weighing 180–220 g were selected and randomly assigned to four groups—acute wound group, chronic wound control group, MEBO group, and positive drug control group—based on a random number table, with 20 rats in each group. All animals were housed and maintained under standardized SPF conditions at the Animal Experimental Center of Youjiang Medical University for Nationalities. An acute full-thickness skin defect wound model was established in the acute wound group, while chronic refractory wound models were induced in the other three groups. During dressing changes, normal saline was applied to the acute wound group and the chronic wound control group based on wound area. The MEBO group received treatment with MEBO at a dosage of 200 mg/cm², and the positive drug control group was administered recombinant bovine basic fibroblast growth factor gel at a dose of 60 IU/cm². Following dressing changes, sterile gauze was used to cover and bandage the wounds in all groups. The wound healing rates in each experimental group were compared on days 3, 5, 7, and 14 after dressing application. Histopathological changes were assessed using H&E staining on days 0, 3, 5, 7, and 14, and semi-quantitative analyses of inflammatory cell infiltration and collagen fiber deposition were conducted. In addition, Western blotting was employed to evaluate the protein expression levels of P53, SLC7A11, and GPX4 in wound tissues on days 3, 5, 7, and 14 post-treatment. Results: The wound healing rates in both the acute wound group and the MEBO group were significantly higher than those in the chronic wound control group (P < 0.05). Additionally, the semi-quantitative scores of inflammatory cells in the acute wound group and the MEBO group were significantly lower than those in the chronic wound control group (P < 0.05). Moreover, the semi-quantitative scores of collagen fibers in both the acute wound group and the MEBO group were markedly higher compared to the chronic wound control group (P < 0.05). There were statistically significant differences in the time, between-group comparisons, and the interaction of P53 protein expression levels among the acute wound group, the chronic wound control group, and the positive drug control group (P < 0.05). Additionally, statistically significant differences in time, between-group effects, and interactions of P53 protein expression levels were observed between the chronic wound control group and the MEBO group (P < 0.05). There were significant differences in the expression levels of the SLC7A11 protein among the acute wound group, the chronic wound control group, and the positive drug control group with respect to time, group, and their interaction (P < 0.05). Additionally, significant differences were observed in SLC7A11 protein expression between the chronic wound control group and the MEBO group in terms of time, group, and their interaction (P < 0.05). There were significant differences in the time course and interaction of GPX4 protein expression among the acute wound group, the chronic wound control group, and the positive drug control group (P < 0.05). However, no significant difference was observed between the two groups (P > 0.05). Additionally, significant differences in GPX4 protein expression were found between the chronic wound control group and the MEBO group in terms of time, group, and their interaction (P < 0.05). Conclusion: MEBO may promote the healing of chronic refractory wounds by regulating the P53/SLC7A11/GPX4 signaling pathway to inhibit ferroptosis in wound tissues during the early stage of wound healing.