Topical formulation of tranilast improves hypertrophic scar in a rat model

Abstract

Introduction: Hypertrophic scars are dermal complication that may lead to considerable morbidity. There is an intense medical need for novel therapies for this disease. Tranilast is an anti-allergic agent that clinically used for the treatment of keloids and hypertrophic scars. In this study, we aimed to evaluate the effect of tranilast 0.5% topical formulation on hypertrophic scars resulted by burn injury in rats. Methods: Burn wounds were inflicted on the skin area of the backs of all rats, following that the scars are created, treatment started and continued for 28 days. Animals were divided into two groups (n=8): the control scar group, which received a placebo and the treatment group that received 0.5% tranilast gel. After this period, skin biopsies were collected from each group for the following analyses. The tissue samples were analyzed by hematoxylin-eosin, Masson’s trichrome staining and qRT-PCR. Results: Histologically, topical tranilast reduced hypertrophic scar signs as compared to placebo. Tranilast treatment also resulted in a reduction in type I and III collagen, transforming growth factor-beta1, Smad2 and vascular endothelial growth factor , and increased Smad7 mRNA expression in the skin scar site. Conclusion: These findings showed that the 0.5% tranilast topical gel could be effective in the treatment of hypertrophic scars in a rat experiment.