Abstract: Objective: To determine the effect of asiaticoside ointment on fibroblast and collagen expression in the keloid model of nude mice. Methods: Keloid tissue was removed and implanted into scapular and sacral tail of 16 nude mice, which were divided into four groups: group A (control group), group B (topical 0.00125% of asiaticoside), group C (topical 0.0025% of asiaticoside), group D (topical 0.005 of asiaticoside), four mice in each group. The change of keloid gross morphology was observed. The expression level of type I collagen in keloid was detected by immunohistochemistry. The changes of fibroblast structure in keloid were observed by projection electron microscopy. Results: Compared to group A, the size of keloid and the number of fibroblasts were decreased in group B-D. The expression rate of collagen in the experimental group A-D was 79.17%, 70.83%, 37.50% and 33.33%, with a significant difference among four groups (Fisher test, P<0.05). Compared to group A, the number of keloid fibroblasts in group B-D was significantly reduced and there were apoptotic cells, retracted  nuclei, unclear cell membrane structure, necrotic cell fragments and fibroblasts in the state of naked nucleus under transmission electron microscopy. Conclusion: Topical application of asiaticoside can reduce keloid fibroblasts and down-regulate type I collagen expression.

Key words: keloid model, asiaticoside ointment, fibroblasts, type I collagen