Effect of Schisandrin B on Dynamic Change of MMP-2 and TIMP-2 Expression in Rat Lungs Exposed to Silica

To investigate the effect of schisandrin B on expression and significance of matrix metalloproteinase(MMP-2) and tissue inhibitor of matrix metall oproteinase(TIMP-2) protein in silica induced pulmonary fibrosis model,the lung injury model was established by a single intratracheal injection of silica.From the first day of exposure of silica,the rats were treated with Sch-B and sacrificed on 3,7,14 and 28 d and lungs were collected.The histopathological of the lungs were observed by HE staining and changs of collagen fibers in the lungs were observed by Masson staining.The MMP-2 and TIMP-2 protein expression were determined by ELISA.The results show that compared with control group,Sch-B improved fibrosis of lungs and reduced collagen fibers.Sch-B could inhibit expression of MMP-2 protein in model rats at every time points,and improve expression of TIMP-2 at the initial stage of rat lungs exposed to silica.Sch-B can inhibit MMP-2 induced lung injury.Sch-B inhibited expression of TIMP-2 at the final stage and reduced pulmonary fibrosis.