Compound Astragalus and Salvia miltiorrhiza Extract Suppresses Rabbits’ Hypertrophic Scar by Modulating the TGF-β/Smad Signal

Abstract

Background: Hypertrophic scar is a fibro-proliferative dis- ease. Our previous studies demonstrate that compound Astragalus and Salvia miltiorrhiza extract (CASE) inhibits pro- liferation and invasion in keloid fibroblasts. Objective: To in- vestigate the effects of CASE on hypertrophic scar. Methods: Rabbits were divided into the control, model and three dos- age groups of CASE (0.94, 1.88, 3.76%). An animal model of hypertrophic scar was established and treated with CASE ointment or ointment base. The histopathological detection by hematoxylin & eosin and Masson’s trichrome staining and protein expression of scars by Western blot were performed. Results: The hydroxyproline content was decreased under CASE treatment. Transforming growth factor beta 1 (TGF-β1) protein expression increased in the model group while it de- creased under CASE treatment. The elevated expression of Smad4 protein was decreased under CASE treatment. Addi- tionally, CASE promoted Smad7 protein expression. Conclusion: CASE could inhibit formation of hypertrophic scar by modulating TGF-β/Smad signal and may be useful for the treatment of hyperplastic scars.