Contribution of glycemic control to the levels of urinary N-acetyl-beta-D-glucosaminidase (NAG) , total protein, beta 2-microglobulin and serum NAG in type 1 (insulin-dependent) diabetes mellitus without macroalbuminuria
Watanabe, Y.; Nunoi, K.; Maki, Y.; Nakamura, Y.; Fujishima, M.
Clinical Nephrology 28(5): 227-231
1987
ISSN/ISBN: 0301-0430 PMID: 3322619 Document Number: 305174
To clarify the significance of the parameters which might indicate the abnormalities in the kidney, urinary N acetyl-.beta.-D-glucosaminidase (NAG), urinary total protein (TP), urinary .beta.2-macroglobulin (.beta.2MG) and serum NAG were determined in 61 type 1 diabetics who had neither retinopathy nor macroalbuminuria (negative albuminuria by Albustix), and in 19 age, sex-matched nondiabetic subjects. Urinary NAG, urinary TP and serum NAG levels were significantly elevated in the diabetics compared with the nondiabetic subjects, even though in the diabetics, whose duration of diabetes was not longer than 2.5 years. The relationships between these parameters and glycemic indices at different periods were studied in diabetics. Urinary NAG was correlated the strongest with the mean blood glucose level over the 7 days before the collection of urine (r = 0.47) among the 5 glycemic indices. On the other hand, urinary TP and urinary .beta.2MG were correlated the strongest with the urinary glucose at the time of collection of urine (r = 0.77 and r = 0.37, respectively) among the 5 glycemic indices. No correlation of urinary NAG, urinary TP or urinary .beta.2MG with stable HbA1 was observed. On the multiple regression analysis, 32% of the changes in urinary NAG, 61% of urinary TP, 19% of urinary .beta.2MG and 20% of serum NAG were explained merely by the blood glucose levels, respectively. No relationship was observed among each parameter and duration of diabetes, insulin dose, urinary excretion of C-peptide or lipid levels. These data suggest that some disorders might develop in both the renal tubules and the glomerulus after short duration of diabetes and also the blood glucose levels for a relatively short period of time may exert influence on these disorders by a different manner.