Effect of Thalidomide on the MMP-2 Protein Expression and Mast Cells in the Lung Fibrosis Induced by Bleomycin in Mice

Introduction and Matrix metallo proteinase-2 (MMP-2) is a family of proteolytic enzymes involved in degrading and remodeling the extracellular matrix and basement membrane. Researchers have shown that Mast cells have an important role in the inflammatory disease including lung fibrosis and they can be as the source of MMP-2 protein. The aim of this research is the examination of Thalidomide effect on the MMP-2 protein expression and Mast cells in the lung fibrosis induced by Bleomycin in mice. In this research, 32 male adult C57BL/6 mices were randomly divided into 4 groups. Mices received in group 1 (Bleomycin) Bleomycin sulfate, in group 2 (Bleomycin+Thalidomide) Bleomycin beside Thalidomide, in group 3(Thalidomide) Thalidomide and in group 4 (Carboxy Methyl Cellulose) Carboxy Methyl Cellulose via intraperitoneum. At the end of experiment, mice’s lung samples were prepared and histological and immunohistochemical studies were performed about them. After the investigation of tissue slides, number of MMP-2 protein expression cells and Mast cells were calculated and results were analyzed by using OneWay ANOVA and Tukey’s test. Histological and immunohistochemical studies showed a significant increase in the number of MMP-2 protein expression and Mast cells in the Bleomycin group in comparison with the Carboxy Methyl Cellulose group (p < 0.001). But number of these cells in the Bleomycin+Thalidomide group decreased significantly compared to the Bleomycin group (p < 0.001). The results showed that the number of expressive cells of MMP-2 protein and Mast cells decreases by Thalidomide and subsequently reduces lung fibrosis in the mice.