Effects of asiaticoside ointment on Smad4 protein expression in rabbit's hypertrophic scars

Objective To investigate the effects of asiaticoside ointment on Smad4 protein expression in rabbit 's hypertrophic scars.Methods The eighteen New Zealand white rabbits were randomly distributed into the control group,the model group and the asiaticoside ointment treatment group. The scars were established on the ventral surface of rabbits' ears in the model and asiaticoside ointment treatment group. On post-operative day 21,the scars of asiaticoside ointment treatment group were thinly daubed with asiaticoside ointment twice a day for 28 days. Meanwhile,those of the control and model groups were applied with ointment base. Morphological characteristics were observed and recorded by a camera every week. All animals were executed and the scars or corresponding skin tissues were harvested for histopathology,hydroxyproline and Smad4 protein detection on post-operative day 49. Results The growth of scars in the model group was more rapid than that of the asiaticoside ointment treatment group. Pathological evaluation shows that representative fibrosis occurred in the scars of the model group,while that was markedly alleviated in the scars of the asiaticoside ointment treatment group. The hydroxyproline content of scars in the model group observably increased compared with that in the control group( P 0. 01),while significantly decreased in the asiaticoside ointment treatment group( P 0. 01). The expression of Smad4 protein was remarkably up-regulated in hypertrophic scar tissue. Nevertheless,it was notably decreased in asiaticoside ointment treatment( P 0. 01). Conclusions The mechanisms of anti-hypertrophic scar effects of asiaticoside maybe involve inhibiting Smad4 protein expression.