The effect of combined steroid and calcium channel blocker injection on human hypertrophic scars in animal model: A new strategy for the treatment of hypertrophic scars

Background Hypertrophic scars (HScs) are inelastic scars that can cause functional loss and disfigurement. Decorin regulates collagen fibrillogenesis, and its expression is lower in HScs than in normal skin and during wound healing. Objective To evaluate the efficacy of combined verapamil and triamcinolone in treating HScs. Methods Excised human HSc fragments from surgically treated burned patients were divided into three groups: A (normal saline), B (verapamil), and C (verapamil and triamcinolone). The specimens were bilaterally implanted in the back of nude mice, treated using intralesional injections, and observed for 4 weeks. We compared the fibroblast viability and proliferation, decorin staining, and scar weights to evaluate treatment efficacy. Results Viability and proliferation of HSc fibroblasts from groups B and C were significantly lower at all time intervals after transplantation (p<.001). Treatment (Groups B and C) stimulated strong decorin staining by 4 weeks. Nonsignificant differences in changes in scar weight were observed between groups. Conclusions We present the first evidence of verapamil-augmented decorin expression spatially correlated with collagen bundles in HScs. Combination therapy can reduce the dosage of each drug but achieve equal or better efficacy than monotherapy, reducing the side effects of a single drug.