Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011849 (diabetes)
 277,896 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Different kidney diseases are often associated with high urinary excretion of N-acetyl-beta-D-glucosaminidase (NAG), a lysosomal enzyme involved in the breakdown of glycoproteins, whose activity is also increased in diabetic patients with poor metabolic control or vascular complications. In order to evaluate the relationship between renal function and urinary NAG levels in diabetes mellitus, 30 type II diabetic patients without evidence of kidney disease and 18 control subjects were studied. In each subject 24-h urinary excretion rates of NAG (fluorimetric method), albumin and beta 2-microglobulin (radioimmunoassay), together with 51Cr-EDTA clearance were performed. In diabetic patients urinary levels of NAG (356 +/- 25 vs 162 +/- 9.2 nmol/h/mg creatinine, p less than 0.0001) and albumin (21 +/- 2.5 vs 4.3 +/- 0.5 mg/24h, p less than 0.0001) were significantly higher than in the controls, while beta 2-microglobulin levels and 51Cr-EDTA clearance did not differ in the two groups. Moreover in diabetic patients NAG and albumin levels were positively and significantly correlated (r = 0.63, p less than 0.001). These results suggest that urinary NAG excretion rate may be altered early in diabetic patients with apparently normal renal function; its diagnostic value seems to be similar to that of the albumin excretion rate.
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PMID:Correlation between urinary activity of N-acetyl-beta-D-glucosaminidase (NAG) and albumin excretion rate in type II (non-insulin-dependent) diabetic subjects. 311 19

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-microglobulin (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.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID: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. 332 19

The pattern of islet lysosomal enzyme activities, islet insulin concentration and the plasma levels of insulin and glucose were studied in freely fed mice after the in vivo administration of diazoxide in doses known to induce crinophagy in islet beta-cells. After diazoxide treatment at time 0 and at 18 hr, the plasma glucose levels at 20 hr were markedly enhanced from 6.6 +/- 0.2 mmol/l (controls) to 27.2 +/- 2.7 mmol/l (diazoxide). Inhibition of insulin secretion by diazoxide was reflected in the insulinogenic index, which was reduced by approximately 40% (p less than 0.01) in the diazoxide-treated animals, who also displayed an increased concentration of islet insulin (+50%; p less than 0.01). Moreover, we found that the activities of certain lysosomal enzymes in islet tissue were markedly increased following diazoxide treatment. Thus the activities of the acid phosphatase, (+57%; p less than 0.02) the hexosaminidase N-acetyl-beta-D-glucosaminidase, (+52%; p less than 0.001), and the carboxyl proteinase cathepsin D (+41%; p less than 0.001), were all enhanced after diazoxide, whereas the activity of another lysosomal enzyme, the glycogen hydrolysing acid amyloglucosidase, was not altered by diazoxide treatment. The present data thus indicate that the morphological observation of diazoxide-induced crinophagy in pancreatic beta-cells has a biochemical correlate in enhanced levels of certain islet lysosomal enzyme activities known to participate in degradative processes. The results also suggest that islet lysosomal enzyme activities and/or lysosome populations can be modulated by a relative independence from each other.
Diabetes Res 1987 Oct
PMID:Biochemical determination of islet lysosomal enzyme activities following crinophagy-stimulating treatment with diazoxide in mice. 332 35

We designed the present study to clarify whether the development of nephropathy was accelerated by a combination of hypertension and non-insulin-dependent diabetes. Spontaneously hypertensive rats with non-insulin-dependent diabetes induced by neonatal streptozotocin treatment (25.0-75.0 mg/kg) were separated into severely or mildly diabetic groups according to their non-fasting plasma glucose levels at 12 weeks of age and the findings were compared with the data on a control group treated with citrate buffer alone. The natural courses of urinary excretion rate of total protein, the molecular composition by sodium dodecyl sulfate polyacrylamide gel electrophoresis with laser densitometer and N-acetyl-beta-D-glucosaminidase were measured in the three groups from 12 weeks until 36 weeks of age. Total urinary protein in the control group decreased with age (p less than 0.05), while in the mildly diabetic group changes were nil; in the severely diabetic group, however, the excretion rates of total urinary protein and high molecular weight protein consistently and progressively increased with age (p less than 0.05). The low molecular weight protein continuously decreased with age in the mildly diabetic and control groups (p less than 0.05), while in the severely diabetic group there was no decrease after 28 weeks of age. The urinary N-acetyl-beta-D-glucosaminidase markedly increased (p less than 0.05) in the severely diabetic group throughout the period compared with findings in the control group, but drastically decreased (p less than 0.05) in the mildly diabetic group with age.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Early development of nephropathy in a new model of spontaneously hypertensive rat with non-insulin-dependent diabetes mellitus. 339 85

Urinary activity of N-acetyl-beta-D-glucosaminidase (NAG) has been suggested as a marker for diabetic nephropathy. In this study, urinary activity of NAG was measured with an interval of 5 yr in 36 insulin-dependent diabetic subjects to evaluate its predictive value for development of diabetic nephropathy. During the observation period, 9 patients developed detectable signs of diabetic nephropathy. In these patients, urinary albumin concentration had increased to 503 +/- 185 mg/L, compared to 16 +/- 1 mg/L in patients without nephropathy (P less than .01; means +/- SE), and the fractional albumin excretion rate was 0.21 +/- 0.07 X 10(-3), compared to 0.01 +/- 0.00 X 10(-3) (P less than .01). However, the activity of urinary NAG was not different in these patients compared with the patients without nephropathy (0.69 +/- 0.15 and 0.61 +/- 0.09 U/mmol creatinine, respectively). Furthermore, no increase in the activity of urinary NAG was seen during the observation period in either group. We concluded that the urinary activity of NAG is not related to the development of microalbuminuria and therefore cannot be used as a predictor for the development of diabetic nephropathy.
Diabetes Care
PMID:Urinary N-acetyl-beta-D-glucosaminidase activity does not predict development of diabetic nephropathy. 367 79

Urinary N-acetyl-beta-D-glucosaminidase (NAG), a lysosomal hydrolase located the proximal tubule of the kidney, has been used as a marker for subtle renal injury. In humans and other animals with diabetes mellitus, urinary NAG activity has been shown to increase within 12 hours of the onset of hyperglycemia and glycosuria. Whether the rise in urinary NAG activity is in response to the hyperglycemia or to the osmotic diuresis associated with glycosuria is not known, nor has the time course of the rise in enzyme activity been determined. A study was designed using four groups of dogs to examine these possibilities: group 1 (n = 5), control dogs; group 2 (n = 5), mannitol-infused dogs; group 3 (n = 5), low-glucose dogs; and group 4 (n = 5), high-glucose dogs. In groups 2 and 4, mannitol and glucose, respectively, were infused at a rate to double urine flow from the left ureter without altering the contralateral urine volume. In group 3, sufficient glucose was infused to elevate left renal vein glucose level without producing glycosuria. In the control dogs infused with normal saline solution at a constant rate throughout the control and study periods, no differences were found in urinary NAG excretion when data from individual clearance periods were compared for the right and left kidneys. In the low-glucose dogs, urinary NAG/creatinine ratios were significantly increased (P less than 0.01) when the left and right kidneys were compared for the duration of the infusion.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Differential response of urinary N-acetyl-beta-D-glucosaminidase to two osmotic diuretics in the dog. 392 47

Urinary activity of N-acetyl-beta-D-glucosaminidase (NAG) has been used as an indicator of subtle renal injury in a variety of conditions. Such enzyme activity has been shown to be increased in human and other animals with diabetes mellitus. The mechanism of this increase in urinary NAG activity is not known. To determine if the osmotic diuretic effect of the glycosuria could stimulate urinary NAG activity, mannitol was infused into the left renal artery of six dogs to cause a unilateral osmotic diuresis and compared to the right side. During three control periods of 20 minutes, each urinary NAG excretion (expressed in units as the ratio of NAG activity to urinary creatinine, NAG/Cr) was equal from both left and right kidneys, 5.0 +/- 1.5 vs 6.0 +/- 3.6 units, respectively. During the 11 mannitol infusion periods urine volume and sodium excretion rose significantly from the left kidney, .50 +/- 2 to 1.5 +/- .3 ml/min and 21 + 5 to 99 +/- 16 u Eq/min, respectively. However urinary NAG/Cr did not change, 5.0 +/- 1.5 to 5.1 +/- 1.0 units. In six control dogs not infused with mannitol, urinary NAG/Cr tended to rise with time from control to experimental collection periods, 4.7 +/- 2.0 to 8.1 +/- 3.0 respectively; however these are not significantly different. In all dogs urine volume and sodium excretion tended to rise throughout the course of the study due to hydration with normal saline; thus it is possible that the tendency for urinary NAG activity to rise may have been due to the increase in sodium excretion. However, these studies demonstrate that the osmotic diuresis induced by mannitol produced no significant change in urinary NAG activity. Thus it may be that the hyperglycemia itself, and not the glycosuria, produces the increase in urinary NAG activity seen in the diabetic.
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PMID:Acute response of urinary N-acetyl-beta-D-glucosaminidase to mannitol infusion in the dog. 392 4

Tubular function was investigated in patients with diabetic ketoacidosis and those with poorly controlled type I diabetes. Urinary excretion of beta 2 microglobulin and that of certain enzymes: gamma glutamyltransferase, leucine aminopeptidase, and N-acetyl-beta-D-glucosaminidase activities were significantly raised during ketoacidosis in 11 patients compared with healthy controls. In 13 poorly controlled diabetics, tubular electrolyte transport was studied and a significant reduction in tubular phosphate and sodium reabsorption was found. Tubular dysfunction occurring during diabetic ketoacidosis and in poorly controlled diabetics may contribute to the development of diabetic nephropathy.
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PMID:Tubular dysfunction in type I diabetes mellitus. 393 37

A study of four lysosomal glycosidases' activities was carried out on sera from 64 diabetic patients, which revealed important variations in comparison with the activities observed in sera of control subjects. Depending on the type of diabetes mellitus (I, insulin-dependent, or II, non-insulin-dependent), three activities were more or less increased: alpha-L-fucosidase, alpha-D-mannosidase, and N-acetyl-beta-D-glucosaminidase, in agreement with previously published results. Against that, the beta-D-mannosidase activity shows a highly significant decrease in sera from either diabetic type. Up to now, no suitable explanation has been found for these variations occurring in an unusual direction.
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PMID:Decreased serum beta-D-mannosidase activity in diabetic patients, in comparison with other glycosidases. 405 98

Urinary N-acetyl-beta-D-glucosaminidase (NAG), a proximal tubule lysosomal enzyme, has been used as an indicator of subtle renal injury. Since it has been positively and significantly correlated with hemoglobin A1c and microalbuminuria, it has been suggested that this enzyme may also reflect metabolic control. Albumin excretion is exacerbated in adult diabetic individuals during exercise; such exercise-induced albuminuria may be a forerunner of diabetic nephropathy. Metabolic control, degree of exertion, and duration of diabetes have been suggested to influence this increase in albuminuria during exercise. Studies of children are few and have produced inconsistent results. Thus we studied 28 insulin-dependent diabetic children ranging in age from 5 yr to 16 yr and 27 age-matched controls using treadmill exercise; two exercise periods consisting of (1) graded increases in speed and grade at 3-min intervals until exhaustion and (2) a constant speed and grade necessary to produce 2/3-3/4 maximal heart rate for 30 min were performed. Capillary blood glucose, urinary NAG/creatinine (cr) ratios (UNAG/Ucr) and urinary albumin/creatinine ratio (Ualb/Ucr) were measured before and after each exercise period; hemoglobin A1c was also measured. The latter averaged 11.8 +/- 0.6% (mean +/- SEM); contrary to previous studies, this was not correlated with pre- or postexercise UNAG/Ucr. During both exercise periods, blood glucose dropped 271 +/- 19 mg/dl to 213 +/- 21 mg/dl (period 1) and 230 +/- 22 mg/dl to 157 +/- 21 mg/dl (period 2).(ABSTRACT TRUNCATED AT 250 WORDS)
Diabetes Care
PMID:Effect of exercise on urinary N-acetyl-beta-D-glucosaminidase activity and albumin excretion in children with type I diabetes mellitus. 405 33


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