Original Paper Nephron Extra 2012;2:219–232 Urinary Matrix Metalloproteinase Activity in Diabetic Kidney Disease: A Potential Marker of Disease Progression

Matrix metalloproteinases activity Interstitial collagenases Gelatinases Albuminuria Type 2 diabetes mellitus Diabetic kidney disease progression End-stage renal disease Background: Progressive kidney fibrosis, associated with chronic kidney disease (CKD), results from an imbalance in extracellular matrix (ECM) homeostasis. Reduced matrix metalloprotein-ases (MMP) activity causing lower clearance of ECM proteins has been implicated mainly through an overproduction of tissue inhibitors of metalloproteinases (TIMP), but also by reduced MMP synthesis. We tested the hypothesis that MMP activity can be measured in human urine and can be used as a potential biomarker of the progression of diabetic kidney disease (DKD). Methods: An observational prospective study was performed on 102 DKD patients using 21 diabetic pa-tients without kidney disease and 21 healthy volunteers as controls. The Molecular Probes En-zChek Gelatinase/Collagenase Assay Kit were used to determine urinary MMP activity usin