Suture-anchored cutaneous tension induces persistent hypertrophic scarring in a novel murine model [miRNA]

Hypertrophic scars arise from dysregulated wound healing under prolonged mechanical tension, causing disfiguring fibrosis. However, limited preclinical models replicate key features of human tension-induced scarring. We developed an innovative murine model utilizing suture anchoring to impose persistent transverse-axial stretch across healing incisions, mimicking excessive wound tension that leads to hypertrophy clinically. Dorsal paired incisions were generated in mice, with wound edges on the upper back sutured to the rib cage while leaving wound edges on the lower back relaxed. This localized anchoring restrained wound contraction, maintaining high tension throughout remodeling analogous to scars widening under stress. Stretched upper wounds developed profound fibrotic changes compared to relaxed controls. Scars induced by suture-anchored tension displayed macroscopic hypertrophy, hardness, erythema, and pruritis up to 3 months. Histologically, scars induced by suture-anchored tension were hypercellular, hypervascular, hyperproliferative with disorganized extracellular matrix deposition, and displayed molecular hallmarks of hypertrophic fibrosis. MiRNA sequencing revealed the different signature in suture-anchored tension induced hypertrophic scars compared to control normal scars. Overall design: To identify the miRNA differences of hypertrophic scars generated in stretched group (HS) and normal scars formed in control group (NS), miRNA sequencing was conducted upon scar samples 2 weeks post excision. Comparative gene expression profiling analysis of miRNA-seq data for HS and NS.