A study on collagen constitute And affected factors in hypertrophic Scar at different age periods

摘要

Objective: To investigate the difference in ratio of collagen in hypertrophic scar (HS) at different age periods and its causes, in order to provide a theoretical base for its special clinical treatment. Method: The expression of type I, type III collagen, and transforming growth factor-beta1 (TGF-beta1) was measured immunohistochemically in different-age HS and normal skin (NS). All the quantities were analysed. Messenger RNA (mRNA) expressions of collagenase (MMP-1) and tissue inhibitor of metallo-proteinase (TIMP-1) were measured with the in situ hybridization technique. Results: 1. The ratio of type I/type III collagen and the quantification of type I collagen in HS increased compared with NS. The ratio of type I/type III collagen in the 1-19 years old HS group increased compared with the 20-50 years old group. 2. The expression of TGF-beta1 protein in HS was enhanced. The expression of TGF-beta1 in the 1-19 years old HS group significantly increased more than in the 20-50 years old group. 3. A significant increase of expression of TIMP-1 mRNA in HS was observed, but the expression of MMP-1 was lower both in HS and in NS. The expression of TIMP-1 mRNA and the expression of MMP-1 in the HS 1-19 years old group and the 20-50 years old group presented no difference. Conclusion: 1. The significant increase in TGF-beta1, which stimulates fibroblast to synthesize more type I collagen and enhances the ratio of type I/type III collagen, may be a cause of the higher incidence of scarring in the 1-19 years old group (children and teenagers). 2. The higher expression of TIMP-1 mRNA and the lower expression of MMP-1 mRNA are among the factors causing HS. Expressions of TIMP-1 and MMP-1 in HS have no direct relationship to age.