Clinical implications of urine matrix metalloproteinases assay in patients with chronic glomerulonephritis

Aim. Estimation of urinary excretion of matrix metalloproteinases (MMP) and their inhibitors in patients with chronic glomerulonephritis (CGN), specification of the role of MMP and inhibitors as criteria of CGN activity and prognosis.
Material and methods. ELISA was used for measurement of urinary levels of basic proteolysis system components (MMP-2 and MMP-9), tissue inhibitor TIMP-2 and plasminogen activator inhibitor PAI-1 in four groups of patients. Patients of group 1 (n = 23) had CGN with manifest urinary syndrome (US), of group 2 (n = 26) - CGN with nephritic syndrome (NS), of group 3 (n = 22) - CGN with marked proteinuria (PU) and transient renal failure (RF), group 4 (n = 15) - CGN with high PU and persistent RF.
Results. Patients with enhancing CGN activity (marked US, developing NS, acute nephritic syndrome) had balanced elevation of urinary levels of MMP, TIMP and PAI-1. Development of persistent RF in CGN occurred with imbalance between components of proteolysis system - low urine excretion of MMP and elevation of PAI-1. Urine excretion of MMP and TIMP in patients with progressive CGN directly correlated with 24-h PU and negatively correlated with blood serum creatinine. PAI-1 correlated with severity of RF and fibrosis in renal tissue.
Conclusion. Correlation of changes in urinary excretion of MMP, TIMP and PAI-1 with CGN activity, RF and fibrosis in the kidney confirm the importance of the above urinary tests for estimation of local renal proteolysis and validity of their use for monitoring of extracellulary matrix accumulation (fibrosis) in the kidney and for CGN prognosis.

PAI-1, matrix metalloproteinases, tissue inhibitors of matrix metalloproteinases, MMP-2, MMP-9, PAI-1, proteolysis, nephrosclerosis, chronic glomerulonephritis