Reshaped commensal wound microbiome via topical application of Calvatia gigantea extract contributes to faster diabetic wound healing

Background Calvatia gigantea (CG) is widely used as a traditional Chinese medicine for wound treatment. In this study, we aimed to determine the effects of CG extract (CGE) on diabetic wound healing and the commensal wound microbiome.Method A wound model was established using leptin receptor-deficient db/db mice, with untreated mice as the control group and CGE-treated mice as the treatment group. The wound healing rate, inflammation and histology were analyzed. Additionally, wound microbiome was evaluated via 16S ribosomal RNA (rRNA) gene sequencing.Results CGE significantly accelerated the healing of diabetic ulcer wounds, facilitated re-epithelialization, and downregulated the transcription levels of the inflammatory cytokines, interleukin-1 beta and tumor necrosis factor-alpha. Furthermore, CGE treatment positively affected the wound microbiome, promoting diversity of the microbial community and enrichment of Escherichia-Shigella bacteria in the CGE-treated group.Conclusions Overall, CGE enhanced diabetic wound healing by modulating the wound microbiome and facilitating macrophage polarization during inflammation. These findings suggest modulation of the commensal wound microbiome using medicinal plants as a potential therapeutic strategy for diabetic wounds. Graphical Abstract