Topical Isoxsuprine in experimentally induced hypertrophic scar in rabbits

Hypertrophic scars are pathological scars which result from exaggerated skin proliferation following a wound and injury. Although many theories have been implicated for keloidogenesis, the precise pathophysiological cause is still masked. Different treatment strategies have been tried in their management, but there is no satisfactory option for treating hypertrophic scar currently; moreover the standard steroid therapy is associated with numerous local side effects, and there is a need for researches in new treatment options. The aim of this study is to evaluate the role of topical isoxsuprine in experimentally induced hypertrophic scar in rabbits. In the current experimental study, 40 healthy male albino rabbits between 12 and 14 months of age were studied. These rabbits were categorized into five groups: healthy animal group (n = 8), hypertrophic scar without treatment (n = 8), hypertrophic scar treated with triamcinolone acetonide gel (n = 8), and hypertrophic scar treated with isoxsuprine gel (n = 8). Histological assessment of skin biopsy, including the conventional hematoxylin and eosin stain, and immunohistochemistry for transforming the growth factor beta 1 level (TGF-β1) and collagen 3 alpha1 (COLIIIαI) in skin tissue was done. The immunohistochemical score of TGF-β and collagen III was highest in group 2 (hypertrophic scar without treatment), followed by group 3 (hypertrophic scar treated with triamcinolone acetonide gel) and group 4 (hypertrophic scar treated with isoxsuprine gel) - no significant difference between them since p > 0.05, and then by group 1 (healthy control group). Regarding histopathological scores of inflammation, the scar height, and scar index, the scores were highest in was highest in group 2 (hypertrophic scar without treatment), followed by group 3 (hypertrophic scar treated with triamcinolone acetonide gel) and group 4 (hypertrophic scar treated with isoxsuprine gel) - no significant difference between them since p > 0.05, with the exception of index of scar, and then by group 1 (healthy control group). It was concluded that isouxoprine in a topical formulation greatly reduced inflammation and scar formation in deep wounds in a manner comparable to that seen with triamcinolone.