MiR-138/peroxisome proliferator-activated receptor β signaling regulates human hypertrophic scar fibroblast proliferation and movement in vitro.

Excessive scars affect a patient's quality of life, both physically and psychologically, by causing pruritus, pain and contractures. Because there is a poor understanding of the complex mechanisms underlying the processes of hypertrophic scar formation, most therapeutic approaches remain clinically unsatisfactory. In this study, we found that miR-138 was downregulated and peroxisome proliferator-activated receptor (PPARβ) was inversely upregulated in hypertrophic scar tissues compared to in paired normal skin tissues. Using a dual-luciferase assay, we validated that miR138 directly targets PPARβ and regulates its expression at the transcriptional and translational levels. In gain-and-loss experiments, we found that miR-138/PPARβ signaling regulated human hypertrophic scar fibroblast proliferation and movement, and affected scarring-related protein expression, which suggests that miR-138/PPARβ signaling is important for hypertrophic scarring. Thus, our study provides evidence to help determine whether miR-138/PPARβ signaling may be a potential target for hypertrophic scarring management.