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

One membrane-bound alpha-glucosidase and two soluble alpha-glucosidases were isolated from homogenates of the hind-midgut, the main digestive region in Musca domestica larvae. The membrane-bound alpha-glucosidase and the low-Mr soluble alpha-glucosidase hydrolyze maltopentaose better than maltose, maltotriose, and maltotetraose, the reverse being true for the high-Mr soluble alpha-glucosidase. A membrane-bound glucoamylase previously described in Musca domestica midgut was shown by gradient centrifugation and dialysis against EDTA to result from the combined action of an amylase and an alpha-glucosidase. The determination of amylase, alpha-glucosidases, soluble and membrane-bound carboxypeptidase A, membrane-bound aminopeptidase and dipeptidase along the tissue and luminal contents of the hind-midgut is described. The data support a proposal concerned with how starch and protein are digested in Musca domestica larval hind-midguts and where and how midgut glycosidases and peptidases are secreted.
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PMID:Regional distribution and substrate specificity of digestive enzymes involved in terminal digestion in Musca domestica hind-midguts. 180 31

Full-value diets of similar composition were given to male rats weighing 207-230 g, by intravenous (group 1) or intragastric (group 2) routes. The proportion of amino acids, fats and carbohydrates was 9.9:15.7:74.4 (with regard to their calorific value). The diet calorific value comprised 60.6 kcal/rat/day. An average mass increase in group 1 was 2.44 +/- 0.14 g/day, in group 2 - 1.75 +/- 0.11 g/day. The protein content and activities of alpha- and gamma-amylase, invertase, maltase, and glycil-L-leucine dipeptidase were assayed in the intestinal mucosa of the proximal portion of the small intestine in group 1 rats, while a decreased alpha-amylase activity in the distal portion of the small intestine was recorded in the animals of group 2. The mass of the pancreas in the rats of group 1 and 2 was authentically lower than in the control rats which received oral feeding with natural foods. The lowest mass of the pancreas was observed in the rats of group 1. Specific activity of trypsin, lipase and RNase in the pancreatic tissues of rats in groups 1 and 2 was similar. The results of the study have evidenced a lowered function of the digestive system under conditions of artificial feeding, especially in case of intravenous nutrition.
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PMID:[Digestive function of the small intestine and pancreas in rats on artificial feeding]. 309 Jul 82

The circadian rhythms of maltase, alkaline phosphatase and dipeptide hydrolase were assessed in duodenum, proximal, medial and distal parts of the rat small intestine. Functional activities were assessed every 4 hrs for 24 hrs. Patterns of all enzymatic activities were different in different parts. The mucosal protein content in each segment of intestine was constant throughout the 24-hour period.
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PMID:[Circadian rhythmicity of the enzyme activity of different portions of the small intestine]. 353 11

An experiment was conducted to examine the effect of pathogenic Escherichia coli inoculated into the yolk sac of day-old turkeys. Escherichia coli was isolated from the yolk sac of stunted poults and inoculated directly into the yolk sac of day-old birds. Poults were administered either .1 ml of uninoculated sterile Todd-Hewitt broth or .1 ml of a 10(-3) or 10(-2) dilution of a 24-hr E. coli culture containing 3.4 X 10(8) viable bacteria/ml. In addition, poults were fed either 28 or 22% protein diets from 0 to 21 days of age to form a 3 X 2 factorial arrangement. Body weight gain and feed consumption were measured weekly, and dry matter and protein retention and nitrogen-corrected metabolizable energy were measured from 7 to 10 and 17 to 20 days postinoculation. Intestinal mucosal dipeptidase and maltase activities were determined at 21 days of age. Average mortality by 7 days of age was increased from 1 to 36% from the E. coli inoculation of the yolk sac. Escherichia coli significantly depressed body weight gain and feed consumption 27 and 30, 13 and 16, and 6 and 8%, respectively, during the first, second, and third weeks of the experiment but failed to affect feed efficiency. Feeding a 28% protein diet alleviated the depression in feed consumption and body weight gain to some extent compared with a substantial depression at 22% protein. Nitrogen content and gross energy of the excreta were increased by both dilutions of E. coli for the 7 to 10-day period; this was indicative of a malabsorption of nutrients.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Dietary protein and yolk sac inoculation with Escherichia coli in young turkeys. 389 12

Some intestinal enZymes were assayed which were related to: (i) Cellular proliferation, for example, aspartate carbamoyltransferase, thymidine kinase, uridine kinase, and dihydroorotase; (ii) cellular differentiation, for example, lactase, invertase, maltase, alkaline phosphatase, and dipeptidase; and (iii) lysosomes, for example, beta-glucuronidase, acid beta-galactosidase, and acid phosphatase. These enzymatic determinations can be used to distinguish the crypt from the villus during healthy or diseased states.
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PMID:Intestinal enzymes: indicators of proliferation and differentiation in the jejunum. 431 2

The effect of a chronic exposure to sublethal concentration of mercuric chloride (0.3 mg/l) on the activities of some enzymes in the digestive system of the teleost fish Channa punctatus was examined after 15 and 30 days of treatment. Glucose-6-phosphatase was significantly inhibited in the intestine and pyloric caeca. No marked alterations were observed in the activities of maltase and lactase except for elevation in maltase activity and inhibition in lactase activity in the intestine and pyloric caeca after 15 days of treatment. Three peptidases (aminotripeptidase, glycylglycine dipeptidase and glycyl-1-leucine dipeptidase) showed decreased activities in all parts of the digestive system. A decrease was also observed in the activity of lipase except for the stomach where inhibition after 15 days was insignificant. The results indicate that the activities of all the enzymes examined are inhibited in intestine and pyloric caeca and digestion of proteins and lipids may be more affected by mercury than the digestion of some carbohydrates.
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PMID:Changes in the activities of some digestive enzymes of Channa punctatus, exposed chronically to mercuric chloride. 624 41

After twenty weeks of continuous dosing with Trichostrongylus colubriformis larvae substantial, but declining, numbers of worms had persisted in most of the lambs examined, although there were wide inter-individual variations. Mucosal lesions were found in the proximal small intestines of all the infected animals, their severity being directly related to worm burden. Representative brush border enzyme activities analysed in intestinal mucosal extracts from the same lambs showed differing responses. Alkaline phosphatase and glycyl-L-leucine dipeptidase were significantly depleted, whereas maltase activity was only marginally reduced, and leucine aminopeptidase activity was normal. Mucosal acetylcholinesterase activity was significantly elevated in the parasitised animals and, interestingly in view of the postulated role of this enzyme in nematode pathogenicity, the level of activity was directly correlated with individual worm burdens. Intestinal trypsin and chymotrypsin activities were unaffected and the level of superoxide dismutase, an enzyme associated with the inflammatory response, was normal. There were also no consistent changes in the mucosal activities of several enzymes including lactic dehydrogenase, creatine phosphokinase, aldolase, and glutamic oxaloacetate transaminase, whose leakage from damaged or necrotic tissues has been well defined in terms of the concomitant increase in their activity in the circulation. Lambs treated orally with fenbendazole five and/or ten weeks before slaughter either in the presence or absence of continued larval intake, had negligible worm burdens, and showed little evidence of intestinal damage at post mortem. Brush border enzyme levels, with the exception of alkaline phosphatase and, in two cases dipeptidase, were normal in these animals. The activity of alkaline phosphatase was approximately double that in the continuously infected, untreated lambs, but remained markedly lower than in the uninfected controls. The activities of the other enzymes studied, including acetylcholinesterase, were within the control range. In summary, in chronic trichostrongylosis even relatively low nematode burdens were associated with marked pathological and biochemical damage in the intestine with both lesion severity and mucosal acetylcholinesterase activity being directly related to worm numbers. Although morphological integrity was completely restored after anthelmintic treatment, the persistent low activity of brush border alkaline phosphatase coupled with the enzymological findings in untreated, infected animals suggests that recovery of the full functional capability of the intestinal mucosa may take longer.
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PMID:Intestinal enzyme activity in lambs chronically infected with Trichostrongylus colubriformis: effect of anthelmintic treatment. 634 11

Rats were made severely uremic with partial nephrectomy (24-hour creatinine clearance 10% of normal). Jejunal dipeptidase activities (substrates: glycyl-L-leucine, L-alanyl-L-proline, and L-methionyl-L-methionine), disaccharidase activities (maltase, sucrase, trehalase, and lactase) and morphology were studied. A highly significant increase in glycyl-L-leucine and L-methionyl-L-methionine dipeptidases was found in uremic rats compared with controls. Proline dipeptidase activities were unaltered. Disaccharidase activities showed a slight increase in sucrase in uremic rats; otherwise no change was found.
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PMID:Small intestinal dipeptidases and disaccharidases in experimental uremia in rats. 677 73

Brush border membranes from frozen human small intestine have been purified using a method which did not involve the use of EDTA-containing buffers or the disruption of brush border fragments with high concentrations of Tris. On average a 24-fold increase in specific activity of alpha-glucosidase (brush border marker) was obtained in the final preparation which contained insignificant traces of enzyme marker activities from cytosol and lysosomes. The homogenates of human small intestinal mucosa were shown to contain enzymes capable of hydrolysing di-, tri-, and tetrapeptides as well as amino acid- and peptide-2-nephthylamides. Assuming a 100% location of alpha-glucosidase in the brush border membrane, distribution studies indicated that activities against tetrapeptides and leucyl-2-naphthylamide were located exclusively in the brush border membrane. A large proportion of activity against alpha-glutamyl-2-naphthylamide, gamma-glutamyl-2-naphthylamide and glycyl-prolyl-2-naphthylamide were also recovered in the brush border membrane fraction. Depending on the substrate utilized, 33-87% of tripeptidase activity was located in the brush border membrane. However, 58-87% of dipeptidase activity was recovered in the soluble fraction.
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PMID:Peptide hydrolases of the human small intestinal mucosa: distribution of activities between brush border membranes and cytosol. 699 48


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