Relationships between circulating matrix metalloproteinase-2 and -9 and renal function in patients with chronic kidney disease

Background: It has been proven that extracellular matrix turnover is involved in the pathogenesis of various renal fibrosis diseases. Matrix metalloproteinase-2 and -9 (MMP-2 and -9) are the extracellular matrix degrading enzymes that are believed to play important roles in renal diseases. However, the relationship of circulating levels of MMP-2, -9 and serum creatinine in the patients of chronic kidney disease (CKD) has not yet been investigated. Methods: Gelatin zymography and ELISA were employed to measure MMP-2 and MMP-9 activities in the plasma samples of 60 CKD patients and 40 control subjects. Results: Serum creatinine concentrations and MMP-2 activities were significantly higher (p < 0.001) while MMP-9 activity and creatinine clearance (CCr) were significantly lower (p < 0.05 and p < 0.001, respectively) in CKD patients, as compared with those of control subjects. In addition, serum creatinine concentrations correlated with MMP-2 activity (R = 0.288, p < 0.05) and inversely correlated with that of MMP-9 (R = 0.344, p < 0.01). Conclusions: This study demonstrated a correlation between MMP-2, -9 and serum creatinine in CKD patients to suggest that MMP-2 and MMP-9 might contribute in the pathogenesis of CKD.