Expression of MMP-9 and TIMP-1 in lesions of systemic sclerosis and its implications

In order to investigate the role of MMP-9 and TIMP-1 in the pathogenesis of systemic sclerosis, the expression of MMP-9 and TIMP-1 was immunohistochemically detected in skin lesions of the patients with diffuse cutaneous systemic sclerosis, skin lesions of the patients with limited cutaneous systemic sclerosis, and skin tissues of normal subjects. The results showed that the expression of MMP-9 in lesions of diffuse cutaneous systemic sclerosis was significantly lower than that of normal skins (P<0.05). However, no significant difference in the level of MMP-9 in the limited cutaneous systemic sclerosis and normal skin was found. Meanwhile, the expression of TIMP-1 in lesions of diffuse cutaneous systemic sclerosis and limited cutaneous systemic sclerosis were significantly higher than that of normal skins (both P<0.05). It was suggested that the expression of MMP-9 and TIMP-1 might play an important role in the development of systemic sclerosis.