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
Query: EC:3.2.1.26 (
invertase
)
4,927
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Rats eating a diet containing
casein
hydrolysate (10% wt/wt)(diet 3) instead of whole
casein
(diet 1) exhibited increased tolerance to nine consecutive daily injections of 15 mg/kg of 5-fluorouracil (5-FU). The relative nutritional efficiency of diet 3 was significantly higher during 5-FU treatment. Serum albumin levels measured after 5-FU treatment dropped by only 2.7% in diet 3 groups and by 13.5% in diet 1 groups. Serum albumin values for rats on the control diet (Purina lab chow) were comparable to those on diet 1. No 5-FU-related mortality was observed in any of the groups. Intestinal brush border enzymes were determined in a group of rats on diet 1. At the end of 5-FU treatment statistically significant changes were observed:
sucrase
dropped to 30% of control and leucylnaphthylamide-hydrolyzing activity dropped to 19% of control. The activity of gamma-glutamyltransferase did not change significantly. It is postulated that under these circumstances a mixture with a prevalence of free amino acids (
casein
hydrolysate) could be more readily absorbed than a corresponding mixture containing a larger proportion of oligopeptides.
...
PMID:Use of an elemental diet in animals during treatment with 5-fluorouracil (NSC-19893). 1 89
In order to investigate the relationship between dietary amino acids and protein, as well as the activities of intestinal sucrase and leucine aminopeptidase in rats, the effects of an amino acid imbalance on these enzyme activities were studied. The amino acid imbalance was created by adding 8% of an indispensable amino acid mixture lacking threonine to a 6%
casein
diet supplemented with 0.3% methionine. The food intake and growth of rats fed the imbalanced diet ad libitum were depressed, and the segmental weights of the small intestine and its
sucrase
activity were clearly lower than those of rats fed the basal diet. The effect of the imbalanced diet under pair-feeding condition on the
sucrase
activity was similar to that under an ad libitum feeding condition. The food intake and segmental
sucrase
activity, that is,
sucrase
activity per length of the small intestine, of rats injected with cortisol (1 mg/day) and fed the imbalanced diet were not depressed, although administration of insulin (1.5 U/day) had no effect on the food intake or segmental
sucrase
activity. Force-feeding stimulated growth of rats receiving the imbalanced diet, as well as increasing their segmental
sucrase
activities. The effects of these different conditions on the leucine aminopeptidase activity of rats receiving the imbalanced diet were obscure. These results suggest that changes in segmental
sucrase
activity might be mediated by stimulating factors in food intake affected by the composition of ingested amino acids and protein together with sucrose in the gastrointestinal lumen.
...
PMID:Effect of an amino acid imbalance on intestinal sucrase and leucine aminopeptidase activities in rats. 12 Apr 27
In order to investigate the relationship between dietary amino acids and protein, and activities of intestinal sucrase [
EC 3.2.1.26
] and leucine aminopeptidase [EC 3.4.11.1, LAPase] in rats, the effect of supplementation of amino acids into a protein-free diet and a low
casein
diet containing sucrose as the carbohydrate source on these enzyme activities was studied. The segmental weights of the small intestine and its mucosa of rats fed the protein-free diet supplemented with L-methionine or with L-methionine and L-threonine at 0.1 or 0.2% levels were significantly higher than those of rats fed the protein-free diet or one supplemented with L-glutamic acid, but there was no difference in the segmental activities of the
sucrase
and LAPase among rats fed these diets. On the other hand, the supplementation of methionine or methionine plus threonine to the 5% or 10%
casein
diet produced remarkable increases in the segmental weights of the small intestine and its mucosa as well as in the segmental activities of the
sucrase
and LAPase. There was no difference between the segmental
sucrase
activity of rats fed the 10%
casein
diet supplemented with 0.2% methionine ad libitum and that of rats fed this diet under restricted feeding conditions, although the segmental LAPase activity was affected by the amount of food consumed.
...
PMID:Effect of diets supplemented with amino acids on intestinal sucrase and leucine aminopeptidase activities in rats. 50 50
Some diets exert a considerable influence on porphyrin metabolism and induction of microsomal liver enzymes in experimental porphyria induced by hexachlorobenzene (HCB). As HCB and its metabolites come into direct contact with intestinal mucosa, this study investigated the changes in the activities of intestinal disaccharidases and gamma-glutamyl transferase in a model of HCB-induced porphyria. The effects of different diets on enzymatic activities during HCB intoxication were also studied. HCB was administered by gastric tube at 3.5 mmol/kg body weight daily for 90 and 61 days. HCB intoxication strongly diminished the activities of intestinal lactase, maltase,
sucrase
, cellobiase and trechalase. Carbohydrate diets (with 78 weight % glucose or starch), given simultaneously with HCB treatment, exerted a protective effect on disaccharidase activities. These regimens maintained cellobiase and trechalase within the normal levels and even increased maltase. High-fat/high-protein diets (with 30% either butter or sunflower oil and 31%
casein
) aggravated the decrease of all disaccharidases. In contrast with the decrease in disaccharidase activity, intestinal gamma-glutamyl transferase was increased, suggesting multiple mechanisms for the action of HCB intoxication on the intestinal enzyme system. Diet had a pronounced modifying effect.
...
PMID:Changes in some intestinal enzyme activities in experimental hexachlorobenzene-induced porphyria and modifying effects of diet. 288 67
The administration of a carbohydrate-containing diet for 24 hours to rats previously fasted for 3 days led to a twofold increase in total intestinal sucrase and
sucrase
specific activity. The specific activity of maltase was similarly increased, but lactase activity was unaffected. The sucrose-containing diet led to a greater increase in
sucrase
than maltase activity, whereas the converse was true of the maltose-containing diet. A carbohydrate-free isocaloric diet led to a slight increase in the total intestinal sucrase, but
sucrase
specific activity was unchanged. Assay of
sucrase
activity of mixed homogenates from
casein
-fed and sucrose-fed rats or fasted and sucrose-fed animals yielded activities that were additive. The Michaelis constant (Km) of the enzyme hydrolyzing sucrose was similar in the fasted,
casein
-fed, and sucrose-fed rats. The maximal velocity (Vmax) was twice greater in sucrose-fed as compared to
casein
-fed or fasted rats, suggesting an increased quantity of enzyme subsequent to sucrose feeding. Adrenalectomized rats maintained on 1.0% salt intake had
sucrase
and maltase levels comparable to those of controls. Steroid administration did not significantly increase their activities. The response to sucrose feeding was similar in both control and adrenalectomized rats, indicative of the absence of steroidal control on
sucrase
and maltase activity in the adult animal. Studies using intestinal ring preparations indicated that sucrose hydrolysis by the intact cells proceeded more rapidly when animals were fed sucrose. Additional corroboration of the physiologic significance of the increased enzyme levels in homogenates was afforded by intestinal perfusion studies. Sucrose hydrolysis increased twofold and fructose absorption fourfold in animals fed sucrose when compared to either fasted or
casein
-fed rats.
...
PMID:Effect of diet upon intestinal disaccharidases and disaccharide absorption. 601 58
Little is known concerning the effects of elemental diets on bowel adaptation following massive resection. Fourteen of 28 Sprague-Dawley rats (40-45 g) were subjected to a 60% jejunoileal resection. Seven of the resected animals and seven sham-operated controls were then placed on a diet containing all protein in the form of
casein
hydrolysate. The remaining seven resected animals and seven sham-operated controls were placed on a comparable diet in which all the protein was
casein
. Each control animal was paired with a resected animal. After 2 weeks, unidirectional glucose and leucine transport was determined from intestinal sacs made from the proximal 3 cm and distal 3 cm of the remaining bowel. The midportion was used for the determination of mucosal weight and protein and
sucrase
content. When expressed as a percent increase over control values per centimeter of bowel, only
sucrase
levels were significantly elevated in the distal bowel in
casein
hydrolysate-versus
casein
-fed animals. The mucosal protein level, mucosal weight, and glucose uptake did not differ from control values when expressed as a percent change. Leucine uptake was significantly decreased in
casein
hydrolysate-fed animals when compared to that in
casein
-fed animals in both the proximal and distal bowel, again when expressed as a percent change from the control values. The administration of protein in the form of
casein
hydrolysate following massive bowel resection does not adversely affect mucosal hyperplasia occurring after resection but may have an adverse effect on the enhancement of amino acid absorption.
...
PMID:Effect of casein versus casein hydrolysate on mucosal adaptation following massive bowel resection in infant rats. 642 98
Food was given to pigs before weaning to determine whether a hypersensitive response to dietary antigen might be a predisposing factor to postweaning diarrhea. Small amounts of food increased the severity and accelerated the onset of postweaning diarrhea. Postweaning diarrhea was dependent on the presence within the diet of antigenic material (bovine
casein
). A weaning diet, containing little antigenic material (hydrolyzed
casein
), had less effect on
sucrase
concentration in intestinal brush borders than did diets rich in antigens (native
casein
). Seemingly, immune-mediated intestinal damage may predispose the pig to postweaning diarrhea.
...
PMID:The importance of dietary antigen in the cause of postweaning diarrhea in pigs. 649 29
Female rats of the Wistar strain, weighing 40-60 g were used to study the effect of fish meals (Coryphaenoides rupestris, Chimaera monstruosa and Merluccius merluccius) on the disaccharidases and alkaline phosphatase in the small intestine in relation to the control group which consumed
casein
. Fish meal diets diminished lactase and alkaline phosphatase activity, the latter being most remarkable in animals fed Ch. monstruosa meal, while no statistical variations in maltase and
sucrase
activity were observed. Maltase,
sucrase
and lactase activity of animals fed Ch. monstruosa meal dropped in comparison with those fed C. rupestris meal, while the alkaline phosphatase activity showed no significant changes.
...
PMID:[Effect of various fish meals on disaccharidases and alkaline phosphatase of the small intestine in rats]. 681 26
Selected bacteroides species secreted various amounts of protease and glycosidase into their growth medium. Bacteroides vulgatus, distasonis, and ovatus secreted the most (31-60% of total). The secreted protease was similar in action to the protease within the organism, in that it had a broad pH optimum of 6-9, a K(m app.) for
casein
of 0.1 muM, and was inhibited by benzamidine, phenylmethylsulfonyl fluoride, diisopropylfluorophosphate (DIFP), and by an elastase inhibitor, Ac(Ala)(3)AlaCH(2)Cl. Exposure of human brush border preparations to the secreted protease reduced maltase and
sucrase
activities; the reduction could be prevented by DIFP. In contrast, brush border alkaline phosphatase activity either did not change or increased after exposure to bacterial secretions. >90% inhibition of secreted glycosidase using EDTA and p-chloromercuribenzoic acid did not prevent the reduction of brush border maltase and
sucrase
activity, suggesting that glucosidases were not likely to be involved in the destruction of brush border enzymes. Moreover, the bacterial proteases caused only a small net release of active maltase or
sucrase
from the brush border. Most of the loss of activity was due to destruction of the enzyme. Proximal bowel fluid of three patients with overgrowth contained DIFP-inhibitable protease that destroyed
sucrase
in isolated brush borders. A Bacteroides species was isolated from each sample that secreted protease and destroyed brush border
sucrase
. We conclude that in bacterial overgrowth syndromes, brush border damage may occur from protease(s) secreted by Bacteroides.
...
PMID:Effect of secreted Bacteroides proteases on human intestinal brush border hydrolases. 699 83
The in vitro and in vivo production of hydrogen gas (H2) from various carbohydrates or proteins has been examined in normal rats and in rats infected with the nematode Nippostrongylus brasiliensis. Normal rat fecal homogenates were capable of producing H2 in vitro from glucose, sucrose, xylose, lactulose, bovine serum albumin, or
casein
hydrolysate. Direct injection of glucose, sucrose, xylose, lactulose, bovine serum albumin, or
casein
hydrolysate into the cecum of normal rats resulted in approximately twice as much H2 production in vivo than when these same carbohydrates or proteins were administered to the normal rats by gavage. Partial small intestinal villous atrophy was produced by infecting rats with the nematode N. brasiliensis. Impaired small intestinal cell function and evidence of malabsorption in the nematode-infected rats included: (a) decreased activity of intestinal cell lactase (-43%),
sucrase
(-33%), and alkaline phosphatase (-46%); (b) decreased gut sac uptake of 3-O-(methyl-3H]-D-glucose (-21%) or 1-[carboxyl-14C]-aminocyclopentane-1-carboxylic acid (-28%); and (c) increased (+ 64%-561%) 14CO2 production after D-[U-14C]xylose administration. These rats produced approximately twice as much H2 after gavage administration of glucose, sucrose, xylose, bovine serum albumin, or
casein
hydrolysate compared with normal rats. The present study suggests that H2 analysis may be useful in the evaluation of small intestinal malabsorption states in rats.
...
PMID:Use of hydrogen gas (H2) analysis to assess intestinal absorption. Studies in normal rats and in rats infected with the nematode, Nippostrongylus brasiliensis. 728 87
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