Effects of Apremilast on Induced Hypertrophic Scar of Rabbits

The present study aimed to assess the effect of Apremilast on experimentally induced hypertrophic scars in rabbits. A total of 40 healthy male New Zealand White rabbits between 6 and 12 months of age were assigned to four groups (n=10). Group I consists of apparently healthy control rabbits, in group II, the rabbits with an induced hypertrophic scar received no treatment, except for base gel. In group III, the rabbits with induced hypertrophic scar were treated with triamcinolone acetonide (TAC) 0.1% as standard medication. In group IV, rabbits with induced hypertrophic scars were treated with Apremilast 5%. On the first day, four surgical incisions were made using an 8-mm biopsy punch on the ventral surface of the rabbit ear down to cartilage. The TAC and Apremilast were topically administered to the developed scars on day 31. The results included an examination of skin histopathology, the level of transforming growth factor beta-1 (TGF-β1), and collagen III in skin tissue. In the treatments, the inflammatory score, scar index, as well as immunological scores of TGFβ1 and collagen III, significantly decreased, compared to the hypertrophic induced scar group (P≤ 0.001). Moreover, there was a significant reduction in fibroblast count, compared to the group of induced hypertrophic scars (P<0.05). Apremilast was efficacious in the treatment of hypertrophic scars due to its ability to reduce inflammations and fibroblast counts and scar index. Nonetheless, the reduction of immunological scores was almost comparable to that of topical TAC.