Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.20 (alpha-glucosidase)
 4,237 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Normal arterial foci which take up Evans blue dye (EBD) in vivo are believed to represent atherosclerosis-prone, hemodynamically stressed foci compared to areas which exclude dye. We have used the rabbit EBD model to examine focal aortic hydrolases of blue areas versus white areas, and we report herein significant focal variations of hydrolase activities. Enzymes measured included neutral alpha-glucosidase, N-acetyl-beta-glucosaminidase, alpha-mannosidase, acid alpha-glucosidase, beta-galactosidase, beta-glucuronidase, cathepsin C, and acid cholesteryl esterase (ACE); specific activities were expressed on the basis of tissue DNA. In correlative areas of EBD uptake in normal rabbit aortic arch, ACE activity averaged 17% higher and cathepsin C activity averaged 37% lower than activities of areas free of EBD in the descending thoracic aorta (P less than 0.02). None of the glycosidases studied differed significantly between blue and white aortic areas. These findings indicate that discrete, intrinsic differences of hydrolytic enzyme activities exist in the normal rabbit aorta in areas delineated by in vivo EBD uptake, areas recognized as lesion-prone vs lesion-resistant.
 ...
PMID:Intrinsic focal variations of rabbit aortic hydrolase activities. 276 19

The postnatal development of the gastric mucosa was observed in Long Evans rats. In both pyloric and fundic mucosae, the mitotic index peaked at 5 days of age and then gradually decreased to reach a constant level from 14 days of age onward (P less than 0.05), the germinal region shifted from the deeper area of the mucosae upward to the middle layer. The number of parietal cells increased gradually (P less than 0.05). Gastric pH on the mucosal surface decreased from 6 on the day of birth to about 4 at 7 days of age and to about 2 at 28 days of age. The inverse relationship between the number of parietal cells and pH value on gastric mucosa was found to be highly significant (P less than 0.01). Trehalase and sucrase activities were observed at 7 days of age and lactase and maltase activities from 0 to 14 days of age. In the pyloric mucosae, foveolae containing goblet cells which were positive for Alcian blue-PAS and HID were observed between 0 and 7 days of age. These cells disappeared by 14 days of age concurrently with the decrease in pH value and increase in the number of parietal cells.
 ...
PMID:pH-related differentiation in the epithelia of the gastric mucosa of postnatal rats. 403 97

The localization of disaccharidases in kidney has been studied by means of the multiple indicator dilution technique. A pulse injection of a solution containing Evans blue dye (plasma marker), creatinine (extracellular marker), and a (14)C-labeled disaccharide (lactose, sucrose, maltose, and alphaalpha-trehalose), is made into the renal artery of an anesthetized dog, and the outflow curves are monitored simultaneously from renal venous and urine effluents. Lactose and sucrose have an extracellular distribution. Trehalose and maltose remain extracellular from the postglomerular circulation. About 75% of filtered tracer maltose or trehalose is extracted by the luminal surface of the nephron. Thin-layer chromatography of urine samples shows that all of the excreted (14)C radiolabel is in the form of the injected disaccharide. Following the administration of phlorizin, all of the filtered radioactivity is recoverable in the urine, but chromatography of the urine samples now reveals that there is a significant excretion of [(14)C]glucose, approximating the amount previously extracted under control conditions (in the absence of phlorizin). It has been verified that no hydrolysis of maltose or trehalose to their constituent glucose subunits occurred during the transit of tracer between the point of injection (renal artery), and the point of filtration (glomerular basement membrane). Similarly, after addition of [(14)C]disaccharides to fresh urine there is no chromatographically recoverable [(14)C]glucose. It is concluded that there exist alpha-glucosidases with maltase and trehalase activity along the brush border of the proximal tubule and that these disaccharidases are located spatially superficial to the glucose transport receptors.
 ...
PMID:Brush border disaccharidases in dog kidney and their spatial relationship to glucose transport receptors. 472 44

The recently developed Otsuka Long-Evans Tokushima Fatty (OLETF) rat is known to develop insulinopenic diabetes after a prolonged period in a condition resembling non-insulin-dependent diabetes mellitus (NIDDM). We examined the effect of pharmacological intervention with a potent intestinal alpha-glucosidase inhibitor, acarbose, on the metabolic and histopathologic changes in this rat model. The first two groups of rats received an acarbose-rich diet (150 mg/100 g normal chow) from 12 weeks of age (ie, before the onset of diabetes) or from 28 weeks of age (ie, after the onset of diabetes), while a third group received the acarbose-rich diet for the initial 16 weeks only (from 12 to 28 weeks of age). A control group received standard rat chow. Acarbose-fed rats gained less weight or lost weight despite increased food intake when switched to the acarbose-rich diet. Acarbose also reduced visceral adipose depots and fasting triglyceride (TG), glucose, and insulin levels. At the end of the study at 72 weeks, the pancreatic wet weight and insulin content were significantly higher in the treated groups versus control rats. The morphological changes observed in control rats, such as atrophy of the pancreas and reduced number and size of islets, were not present in acarbose-treated rats. Rats fed acarbose from 12 to 28 weeks of age gradually gained weight after switching to standard chow, and hyperinsulinemia, hyperglycemia, and hyperlipidemia appeared (in that order). The pancreatic insulin content in these rats was significantly higher and the visceral adipose depot was significantly smaller than in control rats. Our study demonstrates that acarbose prevented and reversed the metabolic derangement and histopathological changes in genetically diabetic rats. Moreover, treatment with acarbose even for a short period produced a marked delay in the development of insulin insensitivity and frank diabetes.
 ...
PMID:Metabolic abnormalities in the genetically obese and diabetic Otsuka Long-Evans Tokushima Fatty rat can be prevented and reversed by alpha-glucosidase inhibitor. 1009 12

Oral administration of alpha-glucosidase inhibitor reduces postprandial serum glucose and insulin concentrations; thus, alpha-glucosidase inhibitor is used for the treatment of diabetes mellitus worldwide. In our study, we have evaluated the effect of alpha-glucosidase inhibitor, acarbose, on age-related glucose intolerance and pancreatic atrophy in the Long-Evans Tokushima Otsuka (LETO) rat. The first group of rats received a standard rat diet (control). The second group received a diet containing acarbose (150 mg/100 g food) from 12 to 28 weeks and then switched to a standard rat diet until 72 weeks of age (A12-28W). The third group was administered the same diet containing acarbose from 12 to 72 weeks of age (A12-72W). Fasting serum glucose and insulin concentrations gradually increased with increasing age in the control group, but these increases were completely prevented (A12-72W) or delayed (A12-28W) by acarbose treatment. In addition, acarbose treatment prevented the deterioration in insulin resistance with increasing age. At 72 weeks of age, pancreatic wet weight and DNA content in the A12-72W group were significantly higher than those in the control group. Although most islets were enlarged, and some portions of pancreatic tissue contained fatty and connective tissue in the control group, these alterations were mild in the A12-28W group and remained minimal in the A12-72W group. Our study suggests that acarbose is useful in the prevention of age-related glucose intolerance and pancreatic atrophy.
 ...
PMID:Effect of inhibition of alpha-glucosidase on age-related glucose intolerance and pancreatic atrophy in rats. 1654 85

The alpha-glucosidase inhibitor 1-deoxynojirimycin (DNJ) is one of the simplest naturally occurring carbohydrate mimics, with promising biological activity in vivo. Although there is considerable interest in the pharmacological effects of DNJ, the antidiabetic effects of DNJ in type 2 diabetes mellitus have received little attention. In this work, DNJ was isolated from the silkworm (Bombyx mori), and its antidiabetic effects were evaluated in Otsuka Long-Evans Tokushima Fatty (OLETF) rats, an established animal model of human type 2 diabetes mellitus, and in control Long-Evans Tokushima Otsuka (LETO) rats. DNJ treatment showed significant antidiabetic effects in OLETF rats, with significant improvements in fasting blood glucose levels and glucose tolerance and, especially, increased insulin sensitivity. Furthermore, there was significant loss of body weight in both groups. DNJ also showed significant antihyperglycemic effects in streptozotocin- and high-fat-diet-induced hyperglycemic rats. Its efficacy and dose profiles were better than those of acarbose, a typical alpha-glucosidase inhibitor in clinical use. Furthermore, a substantial fraction of DNJ was absorbed into the bloodstream within a few minutes of oral administration. DNJ was also detected in the urine. These findings suggest that its postprandial hypoglycemic effect in the gastrointestinal tract is a possible but insufficient mechanism of action underlying the antidiabetic effects of DNJ. Its antiobesity effect and improvement of insulin sensitivity are other possible antidiabetic effects of DNJ.
 ...
PMID:Antiobesity effects and improvement of insulin sensitivity by 1-deoxynojirimycin in animal models. 1836 57

The Otsuka Long-Evans Tokushima Fatty (OLETF) rat, an animal model of type 2 diabetes, exhibits obesity, hyperglycemia and hyperlipidemia, with late onset of chronic and slowly progressive hyperinsulinemia. In this study, we examined effects of long-term dietary supplementation with the alpha-glucosidase inhibitor miglitol on the development of diabetes and the reduction of beta-cells in the pancreas of OLETF rats. The OLETF rats were fed a control diet or a diet containing 800 ppm miglitol (miglitol diet) for 65 weeks from pre-onset stage (5 weeks old). The non-fasting blood glucose concentrations gradually increased in OLETF rats fed the control diet and, at week 64, were significantly higher than those in OLETF rats fed the miglitol diet and age-matched Long-Evans Tokushima Otsuka (LETO) rats, which are control, non-diabetic, non-obese rats of the same strain. Oral glucose tolerance tests revealed that OLETF rats fed the control diet showed pronounced impaired glucose tolerance, but those fed the miglitol diet did not. Furthermore, insulin concentrations after glucose-loading were significantly lower in OLETF rats fed the control diet than in those fed the miglitol diet. The islets of 65-week-old OLETF rats fed the control diet showed significant fibrosis and loss of beta-cells, while those of age-matched control LETO rats had a normal appearance. Feeding OLETF rats a miglitol diet reduced fibrosis and the loss of beta-cells. Our results suggest that dietary supplementation with miglitol from pre-onset stage in OLETF rats delays the onset and development of diabetes and preserves the insulin secretory function of pancreatic islets.
 ...
PMID:The alpha-glucosidase inhibitor miglitol delays the development of diabetes and dysfunctional insulin secretion in pancreatic beta-cells in OLETF rats. 1981 42