mir-182-5p regulates all three phases of inflammation, proliferation, and remodeling during cutaneous wound healing

Wound healing is a highly programmed process, in which any abnormalities result in scar formation. MicroRNAs are potent regulators affecting wound repair and scarification. However, the function of microRNAs in wound healing is not fully understood. Here, we analyzed the expression and function of microRNAs in patients with cutaneous wounds. Cutaneous wound biopsies from patients with either hypertrophic scarring or normal wound repair were collected during inflammation, proliferation, and remodeling phases. Fourteen candidate microRNAs were selected for expression analysis by qRT-PCR. The expression of genes involved in inflammation, angiogenesis, proliferation, and migration were measured using qRT-PCR. Cell cycle and scratch assays were used to explore the proliferation and migration rates. Flow cytometry analysis was employed to examine TGF-β, αSMA and collagen-I expression. Target gene suggestion was performed using Enrichr tool. The results showed that miR-16-5p, miR-152-3p, miR-125b-5p, miR-34c-5p, and miR-182-5p were revealed to be differentially expressed between scarring and non-scarring wounds. Based on the expression patterns obtained, miR-182-5p was selected for functional studies. miR-182-5p induced RELA expression synergistically upon IL-6 induction in keratinocytes and promoted angiogenesis. miR-182-5p prevented keratinocyte migration, while overexpressed TGF-β3 following induction of inflammation. Moreover, miR-182-5p enhanced fibroblast proliferation, migration, differentiation, and collagen-1 expression. FoxO1 and FoxO3 were found to potentially serve as putative gene targets of miR-182-5p. In conclusion, miR-182-5p is differentially expressed between scarring and non-scarring wounds and affect the behavior of cells involved in cutaneous wound healing. Deregulated expression of miR-182-5p adversely affects the proper transition of wound healing phases, resulting in scar formation.