miR-24-3p obstructs the proliferation and migration of human skin fibroblasts after thermal injury by targeting PPAR-β and positively regulated by NF-κB.

Thermal injury repair is a complex process during which the maintenance of the proliferation and migration of human skin fibroblasts (HSFs) exert a crucial role. MicroRNAs have been proven to exert an essential function in repairing skin burns. This study delves into the regulatory effects of miR-24-3p on the migration and proliferation of HSFs that have sustained a thermal injury, thereby, providing deeper insight into thermal injury repair pathogenesis. The PPAR-β protein expression level progressively increased in a time-dependent manner on the 12th, 24th and 48th hour following the thermal injury of the HSFs. The knockdown of PPAR-β markedly suppressed the proliferation of and migration of HSF. Following thermal injury, the knockdown also promoted the inflammatory cytokine IL-6, TNF-α, PTGS-2 and P65 expression. PPAR-β contrastingly exhibited an opposite trend. A targeted relationship between PPAR-β and miR-24-3p was predicted and verified. miR-24-3p inhibited thermal injured HSF proliferation and migration and facilitated inflammatory cytokine expression through the regulation of PPAR-β. p65 directly targeted the transcriptional precursor of miR-24 and promoted miR-24 expression. A negative correlation between miR-24-3p expression level and PPAR-β expression level in rats' burnt dermal tissues was observed. Our findings reveal that miR-24-3p is conducive to rehabilitating the denatured dermis, which may be beneficial in providing effective therapy of skin burns.