Expression of Matrix Metalloproteinase-9 and Tissue Inhibitor of Matrix Metalloproteinase-1 in Serum of Coal Workers' Pneumoconiosis

[Objective]To investigate the relationship between matrix metalloproteinase 9(MMP9),tissue inhibitor of matrix metalloproteinase 1(TIMP1)and coal workers' pneumoconiosis(CWP).[Methods]The concentration of MMP9 and TIMP1 in serum of controls,dust-exposed workers and different categories of CWP in males were determined by ELISA, the corresponding ratios of MMP9 and TIMP1 were calculated and Multinomial Logistic Regression was applied for adjusting the confounding effect of age and mining tenure.[Results]Dust-exposure miners had significantly higher concentrations of MMP9 compared with controls,but there is no significance of that of TIMP1.There was an increasing trend of concentrations of MMP9 and TIMP1 in all CWP patients,but a degradation trend of the ratios of MMP9 to TIMP1 with the advancement of CWP category when compared with controls.After adjusting for mining tenure,there were significant increases of concentration of TIMP1 in categoryⅠCWP and concentrations of MMP9 and TIMP1 in categoryⅢCWP compared with controls.It was also shown that the similar degradation trend of ratios of MMP9 to TIMP1 existed with the advancement of CWP categories.[Conclusion]The balance of MMP9 and TIMP1 might affect the occurrence and development of CWP.