title: Serum N-acetyl-beta-D-glucosaminidase profiles in type 1 diabetes secondary complications: causes of changes and significance of determination.
abstract: The connection between changes in the activity of serum N-acetyl-beta-D-glucosaminidase (NAG, E.C.3.2.1.30) and iso-enzymes and degree of secondary complications was analyzed in four groups of type 1 diabetic patients (n=69): without complications (n=22); with retinopathy (n=16); with retinopathy and polyneuropathy (n=13), and with retinopathy, neuropathy, and nephropathy (n=18). In all groups statistically significant higher (P<0.001) percent fraction of A form (83.84+/-6.09, 84.37+/-5.74, 81.76+/-6.02, 76.37+/-7.38%, resp.) and lower (P<0.001, P<0.01) fraction of B form (15.87+/-5.65, 15.66+/-5.74, 18.33+/-5.98, 23.63+/-7.38, resp.) in total NAG compared with the control (A=69.38+/-4.79%, B=30.61+/-4.78%) were found. The differences in A as well as B forms between diabetic groups were not statistically significant. Significant strong positive correlations between total NAG and glycemia (0.494-0.623), total NAG and A form (0.934-0.966), and A form and glycemia (0.512-0.638) were found in all groups. No correlation was found between the fractions of B and A forms, except in the fourth group. The A form of diabetic patients in the fourth group was more acidic compared with the control and other diabetic groups. It was concluded that the changes in serum NAG and iso-enzymic profiles in diabetes are the consequence of its increased exocytose, especially of the A form, in hyperglycemia and posttranslational modifications of iso-enzymes. The total activity of serum NAG and iso-enzymic profiles cannot be used for monitoring the development and distinction of type 1 diabetes secondary complications.
authors.affiliation: Faculty of Chemistry, Department of Biochemistry, University of Belgrade, Belgrade, Serbia.
authors.forename: V B
authors.initials: VB
authors.lastname: Jovanović
authors.forename: V S
authors.initials: VS
authors.lastname: Dimitrijević-Srecković
authors.forename: Ljuba M
authors.initials: LM
authors.lastname: Mandić
mesh_terms: D000118:Acetylglucosaminidase / Q000097:blood*; D000328:Adult; D048909:Diabetes Complications / Q000097:blood / Q000175:diagnosis / Q000201:enzymology*; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000175:diagnosis / Q000201:enzymology*; D003928:Diabetic Nephropathies / Q000097:blood / Q000175:diagnosis / Q000201:enzymology; D003929:Diabetic Neuropathies / Q000097:blood / Q000175:diagnosis / Q000201:enzymology; D003930:Diabetic Retinopathy / Q000097:blood / Q000175:diagnosis / Q000201:enzymology; D018450:Disease Progression; D005260:Female; D006801:Humans; D007527:Isoenzymes; D008297:Male
chemical_list: D007527:Isoenzymes; D000118:Acetylglucosaminidase