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

The effect of a new complex oligosaccharide (Bay g 5421) of microbial origin on human intestinal alpha-glucosidehydrolase activity was tested in mucosal homogenate from human small bowel biopsy specimens. The alpha-glucosidehydrolase inhibitor (alpha-GHI) exerted a potent inhibitory effect on glucoamylase, sucrase, and maltase, was minimally effective on isomaltase, and did not affect trehalase and lactase activity. Kinetic analysis revealed a fully competitive type of inhibition with a Ki of 1.3 x 10(-6) M; thus the inhibitor had a 15,000-fold higher affinity to the enzyme sucrase than its natural substrate sucrose. The new compound may prove to be useful in the study of carbohydrate maldigestion and malabsorption and may possibly be of therapeutic benefit in diabetes and obesity.
 ...
PMID:Inhibition of human intestinal alpha-glucosidehydrolases by a new complex oligosaccharide. 44 22

Trehalase (an enzyme decomposing the disaccharide trehalose) activity was studied in 29 healthy subjects, 25 patients with cirrhosis and 112 diabetics. Mean trehalase activity was 176 +/- 11 units in the control group, 647 +/- 421 units in the patients with cirrhosis and 467 +/- 239 units in diabetics. The differences between the control group on the one hand and the groups with cirrhosis and diabetes on the other were statistically significant. The results show that the organism, under pathological conditions, makes far greater use of its enzymatic apparatus to assure its basic requirements, but the scatter of the values is so great that the determination of trehalase has no discriminative value in individual cases.
 ...
PMID:Trehalase activity in diabetes mellitus and in cirrhosis of the liver. 61 63

Endogeneous hyperglucagonemia is observed in experimental diabetes mellitus and semistarvation, conditions associated with an increased intestinal absorptive function. To examine whether glucagon might exert a similar adaptive response on intestinal digestive-absorptive function like experimental diabetes mellitus the effect of chronic glucagon administration on intestinal transport of 3-0-methyl-D-glucose, water, sodium, potassium, and D-glucose induced transmural potential difference (PD) was examined by an in vivo perfusion technique in rat small intestine. Chronic administration of glucagon (100 mug twice daily) for 5 days resulted in increased absorption of 3-0-methyl-D-glucose, water, sodium and potassium as well as in an increase of D-glucose induced PD. A similar, but more pronounced augmentation of D-glucose induced PD was observed in the jejunum of streptozotocin-diabetic rats. Disaccharidase (maltase, sucrase, trehalase, lactase) and alkaline phosphatase activities were not affected in intestinal mucosa of glucagon-treated rats compared to controls. It cannot be decided from these results whether hyperglucagonemia is responsible for the adaptive intestinal changes observed in experimental diabetes mellitus.
 ...
PMID:Effect of chronic glucagon-administration on the digestive and absorptive function of rat small intestine in vivo. 98 1

Digestive enzymatic activities (disaccharidases, alkaline phosphatase, peptide hydrolases) have been determined in the mucosa of 14 patients with chronic pancreatitis. All had an abnormal secretin-pancreozymin test. Four patients had insulin-dependent diabetes mellitus, four a pathological glucose tolerance test. Nine patients had steatorrhoea. Maltase, sucrase, and alkaline phosphatase activity was significantly elevated in patients with exocrine pancreatic insufficiency, whereas those of lactase, trehalase, and peptide hydrolase were normal. Patients with steatorrhoea had higher maltase and sucrase activity than those without steatorrhoea, whereas decreased glucose tolerance had no effect on brush border enzymatic activity. It is suggested thatdecreased exocrine rather than decreased endocrine pancreatic function is responsible for the increase in intestinal disaccharidase and alkaline phosphatase activity, possible by the influence of pacreatic enzymes on the turnover of brush border enzymes from the luminal side of the mucosal membranes or by direct hormonal stimulation though cholecystokinin.
 ...
PMID:Influence of exocrine and endocrine pancreatic function on intestinal brush border enaymatic activities. 109 2

Trehalase is an enzyme which hydrolyzes the disaccharide trehalose, yielding glucose. It is widespread in nature and found in various human tissues as well as in human plasma. The synthesis and degradation of its substrate trehalose have been considered as being implicated in carbohydrate transport mechanisms. Trehalase activity has been examined in both normal subjects and diabetic patients. In the normal subjects, the frequency histogram of the enzyme activity is bimodal, indicating the existence of genetic polymorphism. The proposed model of a single autosomal locus with two alleles has been verified, with 27% of the population tested belonging to the "low-activity" phenotype and 73% being of the "high-activity" phenotype. Males have higher mean plasma trehalase activity than females. Apparently, the reverse appears to be the case in the diabetic subjects. The mean value for all nondiabetics and that of diabetics were computed and the difference was found to be statistically significant (F = 7.02, N1 = 3, N2 = 56, P less than 0.01). An experiment showed that neither the abnormally high concentration of glucose in diabetics nor any other constituent of the diabetic plasma caused an increase in plasma trehalase activity (t = 0.0724, P greater than 0.10). A Woolf and Haldane test to determine association of diabetes mellitus and plasma trehalase phenotype indicated a highly significant association with the high-activity phenotype (chi 2 = 18.5350, P less than 0.01). Thus the inference is that people with high plasma trehalase activity are more prone to develop diabetes mellitus than people with low enzyme activity.
 ...
PMID:Plasma trehalase activity and diabetes mellitus. 261 9

The specific activities of membrane-bound maltase (alpha-D-glucoside glucohydrolase, EC 3.2.1.20) in isolated brush border membranes (BBMs) of alloxan-induced diabetic, glucose-infused and maltose-infused rabbits were 30%, 140% and 160%, respectively, of those of control rabbits. Differences in the relative activities of trehalase (EC 3.2.1.28), another disaccharidase, in these groups were similar but less marked. However, the activities of two other marker enzymes of the brush border, alkaline-phosphatase and gamma-glutamyl transpeptidase, were similar in the 4 groups of rabbits. The decreases in the activities of the two disaccharidases were due to changes in the Vmax values of the enzymes without change in their Km values for maltose and trehalose. The maltase activities in the 4 groups showed similar dependences on Tris-HCl, KCl and NaCl. The electrophoretic profiles of the BBMs of the 4 groups on SDS-polyacrylamide gel showed slight differences. From these results, we conclude that diabetes, glucose infusion and maltose infusion probably change the concentrations of active enzymes in the BBM of the kidney in rabbits.
 ...
PMID:Comparisons of maltase activities in kidney brush border membranes from normal, diabetic, glucose-infused and maltose-infused rabbits. 266 45

MDL 25,637 is a novel compound designed as a transition-state inhibitor of alpha-glucohydrolases. This compound inhibits rat intestinal sucrase, maltase, isomaltase, glucoamylase and trehalase activities at micromolar concentrations. It is a much weaker inhibitor of alpha-amylase and lactase. Inhibition of sucrase was competitive with sucrose. In mice, MDL 25,637 inhibited the rise in serum glucose after a sucrose or starch load but not after a glucose load. MDL 25,637 also reduced the glycemic response to sucrose in rats. The drug was most effective when administered 0 to 30 min before the sucrose load and was as effective in streptozotocin-treated rats as in normals. The inhibition by MDL 25,637 of intestinal glucohydrolases is an effective means of reducing the hyperglycemic response to an oral sucrose or starch load and, as such, warrants further investigation as a potential drug for the treatment of diabetes mellitus.
 ...
PMID:Inhibition of intestinal disaccharidases and suppression of blood glucose by a new alpha-glucohydrolase inhibitor--MDL 25,637. 329 22

Trehalase activity was determined in serum, liver, and kidney in alloxan treated Swiss mice and in homozygous (Ob/Ob, Db/Db) and heterozygous (Ob/+, Db/m+) diabetic mice. Both alloxan and genetic diabetic mice exhibited a large increase in serum and liver trehalase activity with no change in kidney trehalase activity. The heterozygotes (Ob/+, Db/m+) showed only a slight increase of enzyme activity. Further quantitative differences were noticed between the genetic and alloxan diabetic animals. The liver enzyme activity increased from 10- to more than 20-fold in the liver of the homozygous Ob/Ob and Db/Db strains and only 3-fold (not significant compared to controls) in the alloxan treated animals. The above results suggest a regulatory relationship between the genes coding for trehalase and the enzymes of glucose metabolism activity involved in the development of the metabolic anomalies of diabetes. The structural gene for trehalase may well have survived elimination of selective pressure during phylogenesis and remained part of a co-regulated group of glucose metabolising enzymes. This could explain its sensitivity to mutations affecting glucose metabolism and its sensitivity to insulin directed regulatory mechanisms.
 ...
PMID:Trehalase activity in genetically diabetic mice (serum, kidney, and liver). 733

Activities of intestinal enzymes were measured in genetically diabetic mouse of strain C57BL/KsJ-dbm to determine the long-term effects of genetic and uncontrolled diabetes on intestinal digestive function. Specific activities of enzymes were measured in intestinal homogenates, brush-border membrane fractions, and everted sacs from diabetic mice and their littermate controls. Sucrase, maltase, trehalase, alkaline phosphatase, and leucylnaphthylamidase activities were elevated in diabetes; lactase did not show any changes. The increases in disaccharidase activities in diabetes were in homogenates from both proximal and distal intestine but the increases in distal were more pronounced than in the proximal. Measurement of enzyme activities in brush-border membrane fractions showed a pattern similar to that observed in homogenates. Hydrolysis of sucrose and trehalose by everted sacs was markedly higher in the diabetic mice. It is therefore concluded that in genetic diabetes the digestive function of the intestine is stimulated, that the increased enzymes were incorporated into the brush-border membrane, and that the additional enzymes are accessible to the substrates in the intestinal lumen and so of physiological significance.
 ...
PMID:Effect of genetic diabetes on enzymes of mouse intestinal brush-border membrane. 736 98

Nineteen healthy volunteers, made up of two groups were subjected to an extended oral glucose tolerance study. In one group, each had 50g glucose and in the other a high carbohydrate meal. Blood glucose and serum trehalase activities were determined on fasting blood samples and specimens collected half-hourly for 4 hours. The values obtained for both at each stage of the investigations were compared with one another. Correlation coefficient (r) between blood glucose and serum trehalase were 0.4923 for the fasting samples and 0.4762 at 1 hr. The impact of diabetes and glycosuria on serum trehalase activities in 50 diabetics consisting of treated (controlled) and untreated (uncontrolled) cases was also studied. Our study reveals a slight fall in serum trehalase values from the initial fasting level, but thereafter a gradual and progressive rise during the course of the glucose tolerance investigations. Serum trehalase values were higher in diabetics compared to normal subjects (t = 7.0168, P = 0.005). Diabetics with glycosuria had a significantly higher mean serum trehalase compared to the controlled group (t = 5.233, P = 0.005). High serum trehalase values were seen in diabetics with renal glycosuria at comparatively low levels of blood glucose. The significance of these findings is discussed in relation to the possible place of serum trehalase assay in the management of diabetes, especially when this is made difficult by renal glycosuria.
 ...
PMID:Serum trehalase activities in controlled and uncontrolled diabetes and the impact of oral glucose, high carbohydrate and glycosuria on serum levels. 783 97


1 2 Next >>