Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.4.21.4 (trypsin)
42,187 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Oral pancreatic enzyme replacement therapy generally benefits patients with severe pancreatic deficiency. However, the fate of oral pancreatic supplements in the digestive lumen and their possible effects on circulating gut hormones are only partially known. The purpose of this article is to validate an experimental model that produces total pancreatic insufficiency in pigs, and to study the fate of orally administered Eurobiol, a whole pancreas lyophilized preparation, and its effects on circulating plasma levels of five digestive hormones. Pancreatic insufficiency was created by pancreatic duct ligation, and the duodenal, jejunal and ileal contents were sampled through cannulas before a normal meal and 0.5-24 h later. Blood samples were taken at the same times, and plasma neurotensin, pancreatic polypeptide, secretin, cholecystokinin (CCK), and gastrin were measured. In pigs with pancreatic insufficiency, Eurobiol, given during the meal, induced a significant increase in all enzyme activities in the duodenum and the jejunum, and in the levels of amylase, trypsin, and chymotrypsin in the ileum, relative to placebo. In the duodenum, the peak concentrations of enzyme activities were 19, 11, 17, and 29% (p less than 0.001) of the postprandial peak activities measured in control pigs with an intact pancreas for lipase, amylase, trypsin, and chymotrypsin, respectively. In the jejunum, the same activities were, respectively, 30, 11, 25, and 36% (p less than 0.01-0.001) of normal peaks. In pigs with pancreatic insufficiency, basal and integrated meal-stimulated neurotensin levels were increased; basal, peak, and integrated meal-stimulated pancreatic polypeptide and secretin levels were increased, whereas gastrin and CCK were not different from controls.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Total pancreatic insufficiency in pigs: a model to study intestinal enzymes and plasma levels of digestive hormones after pancreatic supplementation by a whole pancreas preparation. 247 98

Hydrolytic enzymes were measured in gut contents from four sudden death victims. Pancreatic amylase and total protease activities decreased distally from the small bowel to the sigmoid/rectum region of the large intestine, showing that considerable breakdown or inactivation of the enzymes occurred during gut transit. To determine whether pancreatic enzymes were substrates for the gut microflora, mixed populations of bacteria were grown in a 3-stage continuous culture system on a medium that contained pancreatic extract as the sole nitrogen source. The multichamber system (MCS) was designed to reproduce in vitro, the low pH, high nutrient, fast growth conditions of the caecum and right colon and the neutral pH, low nutrient, slow growth conditions of the left colon. Results showed that pancreatic amylase was resistant to breakdown by intestinal bacteria compared with the peptide hydrolases in pancreatic secretions. Leucine aminopeptidase, trypsin and to a lesser degree, chymotrypsin, were easily degraded by gut bacteria, but pancreatic elastase was comparatively resistant to breakdown. Protein degradation in the MCS, as determined by enzyme activities, protein concentration and ammonia and phenol production, increased concomitantly with system retention time over the range 24-69 h. These results suggest that intestinal bacteria play an important role in the breakdown of hydrolytic enzymes secreted by the pancreas and that this process and protein fermentation in general, is likely to occur maximally in individuals with extended colonic retention times.
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PMID:Influence of retention time on degradation of pancreatic enzymes by human colonic bacteria grown in a 3-stage continuous culture system. 248 Mar 41

The author examined a group of 143 patients with osteomalacia of different origin before treatment and after adequate treatment with vitamin D, using laboratory tests, assessment of body weight and muscular strength (grip of the dominant hand). After treatment there was a significant rise of calcaemia, phosphataemia and calciuria and a drop of alkaline phosphatase activity. The body weight increased within the first month of treatment on average by 1.27 kg, during the second month by another 1.15 kg. The patients gained a total of 2.42 kg. The muscular strength increased during the first month on average by 3.23 kg and during the second month by another 2.16 kg, i.e. a total of 5.39 kg. From these results it may be concluded that vitamin D may have a certain anabolic effect if used in pharmacological does either due to an increased nutrient absorption from the gut because of hypertrophy of the intestinal wall or indirectly via hypercalcaemia which increases the hydrochloric acid secretion in the stomach as well as pepsin secretion, and promotes activation of trypsin and lipase in the duodenum and moreover causes retardation of the intestinal transit. The increased muscular strength in due to a rise of calcaemia, improved muscle contraction and probably also due to the mentioned nutritional factors. There may be also the factor of an improved lifestyle due to the immunomodulating action of vitamin D and disappearance of bone pain.
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PMID:[Anabolic effects of vitamin D in patients with osteomalacia]. 263 59

Hydrolysis of ursodeoxycholyl-p-aminobenzoic acid (PABA-UDCA), a synthetic bile acid conjugate used for the evaluation of the activity of intestinal bacterial growth, was studied with pancreatic enzymes, carboxypeptidase A, carboxypeptidase B, trypsin alpha-chymotrypsin, cholylglycine hydrolase, liver homogenate, small intestinal homogenates, and plasma, in comparison with the hydrolysis of glycocholic acid, ursodeoxycholyl-L-leucine (L-Leu-UDCA), and ursodeoxycholyl-L-lysine (L-Lys-UDCA). PABA-UDCA was specifically cleaved by bacterial cholylglycine hydrolase to ursodeoxycholic acid and para-aminobenzoic acid (PABA), but not by pancreatic enzymes. L-Leu-UDCA was cleaved by pancreatic enzymes, carboxypeptidase A, and cholylglycine hydrolase. L-Lys-UDCA was cleaved by pancreatic enzymes, carboxypeptidase B, and cholylglycine hydrolase. The small amount of glycocholic acid was cleaved by pancreatic enzymes and carboxypeptidase A and B, and cholylglycine hydrolase hydrolyzed glycocholic acid completely. In everted gut sac experiments, PABA-UDCA was absorbed by active transport in the rat terminal ileum, and the same rate of PABA was absorbed by passive diffusion in the four segments of the rat small intestine. These observations indicate that PABA-UDCA test can evaluate the activity of small intestinal bacterial growth.
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PMID:Hydrolysis and absorption of a conjugate of ursodeoxycholic acid with para-aminobenzoic acid. 263 32

We tested four synthetic substances for their histochemical value to demonstrate the catalytic activities of chymase or tryptase in mast cells in sections of human gut. Both Suc-Ala-Ala-Phe-4 methoxy-2-naphthylamide (MNA) and N-acetyl-L-methionine-alpha-naphthyl ester (alpha-N-O-Met) reacted with chymase but not tryptase in mast cells. Conversely, D-Val-Leu-Arg-MNA and Z-Ala-Ala-Lys-MNA were hydrolyzed by mast cell tryptase but not chymase. These results were confirmed by use of two inhibitors of chymotrypsin-like activity, chymostatin and Z-Gly-Leu-Phe-chloromethyl ketone (CK) and two inhibitors of trypsin-like activity, Tos-Lys-CK and D-Val-Leu-Arg-CK. Excellent staining reactions were obtained on cryostat sections of unfixed or aldehyde-fixed tissues and on paraffin sections of Carnoy-fixed tissues. For chymase, however, Suc-Ala-Ala-Phe-MNA is preferred on cryostat sections because it is more specific. On paraffin sections alpha-N-O-Met is preferred because other cells are not then stained. For tryptase, Z-Ala-Ala-Lys-MNA was more selective and more specific and is the preferred general purpose substrate on cryostat sections of aldehyde-fixed tissues and for paraffin sections. D-Val-Leu-Arg-MNA is the preferred substrate for cryostat sections of unfixed tissue. Only a limited number of mast cells showed a reaction for chymase, and these occurred mainly in the submucosa. All mast cells, however, gave a reaction for tryptase, and we recommend the use of either substrate for this enzyme for routine detection of mast cells in human tissues. Double staining for the two main mast cell proteases is most conveniently undertaken on paraffin sections of Carnoy-fixed tissues using MNA substrates for tryptase and alpha-N-O-Met for chymase.
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PMID:Enzyme histochemical discrimination between tryptase and chymase in mast cells of human gut. 264 38

Inclusion of raw soyabean in diets considerably inhibits the growth of young animals. This is due to interference with normal gut and systemic metabolism, particularly of pancreas, liver and muscle. Pancreatic hypertrophy and hyperplasia occur in the young of a number of species given soyabean. In the rat, this enlargement, which is primarily a result of interference with CCK-mediated feedback control of exocrine pancreatic secretion, persists upon prolonged feeding and leads to a susceptibility of the pancreas to carcinogens and an increased incidence of neoplasia. In contrast, with pigs or dogs, in which feedback regulation is primarily mediated via secretin, no increase in pancreas enlargement results from consumption of soyabean. Dietary soyabean or trypsin inhibitors do however alter pancreatic secretion in humans. It is at present unclear how this response is mediated. The growth inhibition and interference with intestinal and systemic metabolism observed upon soyabean feeding is due to the presence of trypsin inhibitors, lectin and anti-nutritional factors, devoid of trypsin inhibitory or lectin activity, in the seed meal. The effects of these dietary factors are additive and possibly synergistic. Most of the anti-nutritional effects of soyabean can be abolished by proper aqueous heart-treatment. However, with a proportion of calves, pigs, lambs and humans even heat-treated soyabean has deleterious effects. These can only be eliminated by hot aqueous-ethanol extraction of the meal.
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PMID:Anti-nutritional effects of soyabean: a review. 269 45

It was recently reported that the intestinal protease trypsin cleaves in vitro the VP1 protein of type 3 poliovirus at antigenic site 1 (J. P. Icenogle, P. D. Minor, M. Ferguson, and J. M. Hogle, J. Virol. 60:297-301, 1986). We found that incubation of purified or crude type 3 poliovirus preparations with specimens of human intestinal fluid brings about a similar change in the virion structure. Sera from children immunized solely with the regular inactivated poliovirus vaccine (IPV) neutralized trypsin-cleaved Sabin 3 virus poorly, if at all, despite moderate levels of antibodies to the corresponding intact virus. Sera containing very high titers of the intact virus also neutralized the trypsin-cleaved virus but at a relatively weaker capacity. Most sera from older persons who may have been exposed to a natural poliovirus infection before the introduction of the poliovirus vaccines as well as sera from children infected with type 3 poliovirus during the recent outbreak in Finland were able to neutralize the trypsin-cleaved type 3 polioviruses. Serum specimens collected 1 month after a single dose of live poliovirus vaccine from children previously immunized with IPV were able to neutralize the trypsin-cleaved virus as well. During natural infection and after live poliovirus vaccine administration polioviruses are exposed to proteolytic enzymes in the gut. Our results may offer an alternative explanation for the relatively weak mucosal immunity obtained with IPV. Improvement of IPV preparations by incorporation of trypsin-treated type 3 polioviruses in the vaccine should be studied.
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PMID:Intestinal trypsin can significantly modify antigenic properties of polioviruses: implications for the use of inactivated poliovirus vaccine. 282 12

The mechanism of action and receptor binding of a dual-specificity Bacillus thuringiensis var. aizawai ICl delta-endotoxin was studied using insect cell culture. The native protoxin was labelled with 125I, proteolytically activated and the affinity of the resulting preparations for insect cell-membrane proteins was studied by blotting. The active preparations obtained by various treatments had characteristic specificity associated with unique polypeptides, and showed affinity for different membrane proteins. The lepidopteran-specific preparation (trypsin-treated protoxin containing 58 and 55 kDa polypeptides) bound to two membrane proteins in the lepidopteran cells but none in the dipteran cells. The dipteran-specific preparation (protoxin treated sequentially with trypsin and Aedes aegypti gut proteases, containing a 53 kDa polypeptide) bound to a 90 kDa membrane protein in the dipteran (A. aegypti) cells but bound to none in the lepidopteran cells or Drosophila melanogaster cells. The toxicity of trypsin-activated delta-endotoxin was completely inhibited by preincubation with D-glucose, suggesting a role for this carbohydrate in toxin-receptor interaction. The toxicity was also decreased by osmotic protectants to an extent proportional to their viscometric radius. These results support a proposal that initial interaction of toxin with a unique receptor determines the specificity of the toxin, following which cell death occurs by a mechanism of colloid osmotic lysis.
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PMID:Analysis of the molecular basis of insecticidal specificity of Bacillus thuringiensis crystal delta-endotoxin. 282 19

The native crystal delta-endotoxin produced by Bacillus thuringiensis var. colmeri, serotype 21, is toxic to both lepidopteran (Pieris brassicae) and dipteran (Aedes aegypti) larvae. Solubilization of the crystal delta-endotoxin in alkaline reducing conditions and activation with trypsin and gut extracts from susceptible insects yielded a preparation whose toxicity could be assayed in vitro against a range of insect cell lines. After activation with Aedes aegypti gut extract the preparation was toxic to all of the mosquito cell lines but only one lepidopteran line (Spodoptera frugiperda), whereas an activated preparation produced by treatment with P. brassicae gut enzymes or trypsin was toxic only to lepidopteran cell lines. These in vitro results were paralleled by the results of in vivo bioassays. Gel electrophoretic analysis of the products of these different activation regimes suggested that a 130-kDa protoxin in the native crystal is converted to a 55-kDa lepidopteran-specific toxin by trypsin or P. brassicae enzymes and to a 52-kDa dipteran toxin by A. aegypti enzymes. Two-step activation of the 130-kDa protoxin by successive treatment with trypsin and A. aegypti enzymes further suggested that the 52-kDa dipteran toxin is derived from the 55-kDa lepidopteran toxin by enzymes specific to the mosquito gut. Confirmation of this suggestion was obtained by peptide mapping of these two polypeptides. The native crystal 130 kDa delta-endotoxin and the two insect-specific toxins all cross-reacted with antiserum to B. thuringiensis var. kurstaki P1 lepidopteran toxin. Preincubation of the two activated colmeri toxins with P1 antiserum neutralized their cytotoxicity to both lepidopteran and dipteran cell lines.
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PMID:Specificity of Bacillus thuringiensis var. colmeri insecticidal delta-endotoxin is determined by differential proteolytic processing of the protoxin by larval gut proteases. 300 87

It is now known that nonphysiological cobalamin analogs exist in the gastrointestinal tract, but their metabolic behavior is unclear. In this study, [57Co]cobinamide was used to study its affinity to hog intrinsic factor-cobalamin (IF-Cbl) receptor which has no species specificity against human IF-Cbl receptor, and its relation to human saliva R binder. Cobinamide was prepared from [57Co]cyanocobalamin and separated by paper chromatography. Human IF-Cbl complex was bound to IF-Cbl receptor but free cyanocobalamin was not. Although R binder-cobinamide was not bound to the IF-Cbl receptor, free cobinamide was bound to the IF-Cbl receptor to a significant extent (about one-half of IF-cyanocobalamin binding to the IF-Cbl receptor). We then investigated the binding of cobinamide to R binder and trypsin-treated R binder. Association constant of cobinamide binding to the IF-Cbl receptor was 1.0 X 10(9) M-1 which was much lower than that of cobinamide binding to trypsin-treated R binder and to untreated R binder. Further study indicated that cobinamide binding to the IF-Cbl receptor was blocked by the addition of R binder and also by trypsin-treated R binder. We conclude that one of the roles of R binder is to prevent binding of free cobalamin analogs to the IF-Cbl receptor in the gut.
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PMID:Binding of cobalamin analogs to intrinsic factor-cobalamin receptor and its prevention by R binder. 302 87


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