Diagnostic Significance of Urinary Enzymes for Diabetes mellitus and Hypertension

Abstract

In order to evaluate tubular damage in diabetic patients, the activity of renal proximal tubule derived enzymes excreted in 24-hour urine were recorded in 5 groups as follows: (i) 48 noninsulin-dependent diabetic patients with normal renal function and a urinary albumin excretion rate within the normal range; (ii) 45 noninsulin-dependent diabetic patients with normal renal function and a high urinary albumin level; (iii) 26 noninsulin-dependent diabetic patients with renal failure; (iv) 40 patients with essential hypertension and normal renal function, and (v) 48 normal control subjects. Regardless of whether cases were noninsulin-dependent diabetics with normal or high urinary albumin excretion rate or cases with renal dysfunction, urinary dipeptidyl aminopeptidase IV and N-acetyl-ß-D-glucosaminidase excretions were significantly higher than in healthy subjects, and urinary gamma-glutamyl transpeptidase excretion was significantly lower than in healthy subjects. No significant changes in urinary enzyme excretions showed specific variations in the essential hypertensive patients. These results suggest that there is tubular damage in the early stages of noninsulin-dependent diabetic patients with normal renal function and normal urinary albumin excretion rate. Detection of urinary excretion of dipeptidyl aminopeptidase IV, N-acetyl-ß-D-glucosaminidase and gamma-glutamyl transpeptidase may be especially useful for the early diagnosis of diabetic nephropathy.

The Effects of Dipeptidyl Peptidase-4 Inhibition on Microvascular Diabetes Complications

“…Since the discovery of DPP-4 as an adenosine deaminase binding protein (80), the expression of DPP-4 has been considered a marker of renal injury, including diabetic nephropathy (81)(82)(83). The relationship between DPP-4 activity and kidney function is complex, and available studies frequently report conflicting results.…”

Urinary biomarkers involved in type 2 diabetes: a review

“…Similarly, urine enzymes are highly sensitive markers of renal tubular damage, the most widely used being NAG and alanine aminopeptidase (AAP) 194. Because of their high‐molecular weight, they are not filtered through the glomerulus but originate in the renal tubular cells and are excreted in urine 17, 22, 117, 154, 155. They have, therefore, been used as markers of tubular damage in diabetic renal dysfunction 15, 22, 63, 117, 155, 194.…”

Transmembrane proteases in cell growth and invasion: new contributors to angiogenesis?

“…Overexpression of both membrane and/or soluble forms of MT1-MMP, DPPIV and ACE is correlated to cardiovascular diseases (myocardial infarction, stroke, hypertension) and their complications (atherosclerosis, diabetic nephropathy and retinopathy, vasculitides) (Table 1) (Cambien et al, 1992;Ishii et al, 1994;Vranes et al, 1995;Rajavashisth et al, 1999;Antczak et al, 2001b). TACE and DPPIV are overexpressed in myocarditis (Satoh et al, 2000;Schonermarck et al, 2000).…”