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

On the basis of comparative determinations of the activities of dipeptidases and disaccharidases of the mucous membrane of the small intestine (proximal jejunum) clear correspondences between the morphological findings and the biochemical parameters were the result. L-alanyl-L-prolin-dipeptidase and glycyl-L-valin-dipeptidase as well as lactase, saccharase, maltase and trehalase were determined in altogether 45 children with various malabsorption syndromes of different age in different stages of disease. Diminutions of the activity of the dipeptidases were to be proved analogously to maltase, saccharase and lactase, too, in most cases of subtotal or total villous atrophy. From the results conclusions may be derived to the restricted ability of protein absorption in chronic disease of the small intestine.
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PMID:[L-alanyl-L-proline-dipeptidase and glycyl-L-valine-depeptidase in malabsorption syndrome]. 96 Sep 1

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.
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PMID:Effect of chronic glucagon-administration on the digestive and absorptive function of rat small intestine in vivo. 98 1

Activities of the small intestinal mucosal enzymes lactase, sucrase, maltase, alkaline phosphatase and N-acetyl-beta-glucosaminidase were studied in rats with surgically-induced upper intestinal stasis and in control animals. The first four are brush border enzymes, the latter a lysosomal enzyme. There was a reduction in the activities of all enzymes in the operated animals. The change lining was significant and most marked in mucosa the blind loop and gut distal to it; areas in which there is gross bacterial overgrowth and excessive levels of intraluminal deconjugated bile salts. The significance of these findings in relation to malabsorption consequent on bacterial contamination of the upper gut is uncertain and requires further study.
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PMID:Effect of stasis on intestinal enzyme activities. 105 24

Lactase and cellobiase were detectable in the fetal intestine by the 3rd month of gestation, and although there was little change by the 9th month, maximal levels were reached at birth and steadily declined after 4 months. Conversely maltase, sucrase and trehalase were barely discernible in the fetus, maltase being present at low levels at birth, but all increased during the suckling period to attain adult levels by 7 months of age. Alkaline phosphatase activity matured earlier than did disaccharidase activity. Mucosal enzymes other than alkaline phosphatase were virtually absent from meconium and the large intestine. Continued ingestion of lactose could be detrimental in foals suffering from severe diarrhoea.
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PMID:The development and distribution of mucosal enzymes in the small intestine of the fetus and young foal. 106 Aug 71

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.
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PMID:Influence of exocrine and endocrine pancreatic function on intestinal brush border enaymatic activities. 109 2

About 90% of the protein of hamster intestinal brush borders was solubilised in 0.25% (w/v) sodium dodecyl sulphate without total loss of biological activity. Detergent-polyacrylamide gel electrophoresis of the solubilised proteins separated 10-15 bands and partially resolved maltase, lactase, sucrase-maltase, trehalase and alkaline phosphatase activities. The disaccharidases, which were associated with the higher molecular weight proteins, were preferentially solubilised with 0.1%. (w/v) Triton X-100, butanol or papain, whereas Tris and NaI extracted only the lower molecular weight proteins, possible derived from the core filaments. Electrophoresis of brush border proteins metabolically labelled with [14-C] glucosamine suggested that many of the membrane-bound enzymes are glycoproteins. However, chromatography of a papain digest on Sephadex G-200 showed that the sucrase-maltase complex can be separated nearly free of carbohydrate without total loss of activity. The importance of characterizing membrane proteins solubilised by a number of techniques is discussed.
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PMID:Solubilization of brush borders of hamster small intestine and fractionation of some of the components. 113 70

Feeding sodium deoxycholate orally to rats for four days caused depression of the activity of the small intestinal enzymes lactase, sucrase, maltase, alkaline phosphatase, and N-acetyl-beta-glucosaminidase. The first four are brush border enzymes, the last a lysosomal enzyme. Alkaline phosphatase activity recovered very rapidly and rebounded to above the normal level within 24 hours. The activity of the three disaccharidases returned to normal within seven days while no recovery was observed within 96 hours of the activity of the lysosomal enzyme, N-acetyl-beta-glucosaminidase, after removing the bile salt from the diet.
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PMID:Deoxycholate depresses small-intestinal enzyme activity. 114 Jun 27

1. Intestinal brush border enzymes have heterogeneous rates of turnover, the largest proteins having the fastest turnover. Since the membrane faces the intestinal lumen, the effects of pancreatic factors were examined in mediating this turnover. Surgical subtotal pancreatectomy was used as an experimental model to study the turnover of brush border proteins in the absence of most pancreatic secretions. 2. Subtotal (95%) pancreatectomy of rats was found to cause elevations by about 50% of total activity and specific activities of certain brush border enzymes (maltase, sucrase, lactase), but not of others (alkaline phosphatase, trehalase). Rats were judged to be functionally deficient in pancreatic proteolytic enzymes (a) by demonstration of vitamin B-12 malabsorption, which was corrected by trypsin, and (b) by the finding of only about 20% of proteolytic activity appearing in the lumen after a test meal when compared to control. 3. To measure protein turnover in vivo the method of double labelling was used, where [3H]- and [14C]valine were administered intraduodenally in sequence 10 h apart. With this technique, a high 3H/14C ratio is correlated with rapid turnover. Proteins with apparent molecular weights of about 200 000-270 000 were found to turn over more rapidly than smaller proteins. 3H/14C ranged from 4.7 to 6.2 in animals without pancreatic insufficiency. In the face of decreased pancreatic proteolysis, the 3H/14C ratio was 2.3-3.1, similar to that of proteins with a slow half life. 4. Estimates of relative synthetic rates of large brush border proteins were lower than normal in pancreatectomized animals, but were constant over the period of the labelling experiment. The high enzyme levels in the face of lower synthetic rates confirms that, at the new steady rate, degradation rates must be slower for large brush border proteins in pancreatic insufficiency. 5. In vitro, using purified brush borders, unfractionated pancreatic enzymes were found to remove sucrase, maltase and lactase, but not alkaline phosphatase and trehalase. The enzyme most potent in this respect was the pancreatic protease, elastase. Non-proteolytic enzymes (amylase, lipase, phospholipase A) were inactive in removing enzyme from the brush border. The addition of elastase to pancreatectomized animals in vivo restored the rapid turnover rate of large brush border proteins. 6. A model is thus proposed for the normal catabolism of some large intestinal brush border proteins. It is suggested that the surface of intestinal absorptive cells is being constantly remodelled, and that certain surface enzymes are in part removed from the membrane by the action of pancreatic proteases. A possible special role for elastase is suggested.
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PMID:The possible role of pancreatic proteases in the turnover of intestinal brush border proteins. 114 88

Jejunal biopsies from 19 adult Greenland Eskimos were studied regarding disaccharidases, two intracellular beta-galactosidases, and morphological appearance. Fifteen of the patients (79%) had low lactase activity, and 3 of these (16%) had sucrase-isomaltase deficiency as well. Two patients had low trehalase activity. Microscopical appearance was essentially normal in all the biopsies, except for a certain stromal plasma cell infiltration. All the patients with low lactase activity had a measurable residual activity of brush border lactase, which was localized in the middle and apical parts of villi, as normally seen for digestive enzymes. Lysosomal acid beta-galactosidase and cytosol hetero beta-galactosidase were not altered. In the patients with sucrase-isomaltase deficiency there was a complete absence of active sucrase-isomaltase complex. The residual maltase, as well as the very weak residual isomaltase, was exerted exclusively by the heat stable maltases (maltase II and III). The material is the first one in which multiple, but not generalized disaccharidase deficiencies are demonstrated.
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PMID:Intestinal disaccharidases in Greenland Eskimos. 115 47

Studies have been done on the effect of Penicillin, Streptomycin and Isonicotinic Acid hydrazide on small intestinal oligosaccharidase and it was observed that the drug penicillin inhibited the enzyme lactase and sucrase by 62.7% and 34.7% respectively, whereas I.N.H. inhibited the enzyme sucrase and maltase by 57.1% and 56.14% respectively. Streptomycin did not show any inhibitory effect on those enzymes. Lactose tolerance test showed impairment of lactose absorption in case of penicillin. Fasting serum sugar level was diminished both in penicillin and streptomycin and the absorption capacity was increased after oral administration of streptomycin.
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PMID:Studies on the effect of penicillin, streptomycin and isonicotinic acid hydrazide on small intestinal oligosaccharidase. 115 32


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