Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.26 (invertase)
 4,927 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

General evidence of malnutrition such as loss in body weight associated with intestinal parasitism has been attributed to decreased food intake, to intestinal malabsorption, and to change in host basal metabolism. To establish the relative importance of these factors in this regard, rats with trichinosis were studied. The weights of infected and uninfected animals were followed after being placed on one of three feeding regimens for 1 week--stock diet ad libitum, intraduodenal nutrition, and intravenous nutrition. Infected rats on a stock diet lost weight whereas those on the other two regimens maintained the same weight pattern as uninfected counterparts. The maintainance of body weight occurred despite alterations at the level of the intestinal brush border as indicated by a depression of intestinal disaccharidase activities (sucrase and lactase) and by reduction of monosaccharide absorption (measured as accumulation of beta-methyl glucoside) in the proximal, heavily infected region of the small intestine. There was no compensatory increase in enzyme activity nor in the absorptive capacity in the distal gut. Results support the conclusion that inadequate oral food intake rather than changes in basal metabolism or intestinal pathophysiology accounts for weight loss during the intestinal phase of infection.
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PMID:Enteral and parenteral feeding to evaluate malabsorption in intestinal parasitism. 11 Jan 62

A phytohemagglutinin extract is prepared from raw kidney beans (Phaseolus vulgaris) and incorporated at a level of 1% (dry matter) in the diet of young growing rats. Beside a decrease of feed intakes, the main effects of the experimental diet are the following : growth depression, decrease of dry matter and protein digestibility and hypoglycemia. Biological value, organs weight (liver, kidneys, spleen) did not change significantly. The hemagglutinin extract induces an inhibition of saccharase activity whereas (Na+-K+)-ATPase remains unchanged. Growth depressing effect may be due to an alteration of hydrolysis and absorption mechanisms at the level of brush border of enterocytes.
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PMID:[Effects of a phytohemagglutinin extract on growth, nitrogen digestibility and the activity of invertase and (Na+-K+)-ATPase in the intestinal mucosa of the rat]. 23 10

Jejunal sucrase has been used as a marker for intestinal development. The effects of sequential adrenalectomy and sequential administration of hydrocortisone have led to the conclusion that the glucocorticoid sensitivity of the jejunum ceases abruptly at a postnatal age of 17--18 days. Adrenalectomy on day 17 or earlier resulted in significant depression of the usual developmental rise of sucrase activity, whereas adrenalectomy on days 18, 21, or 28 or in adults had no effect on sucrase activity. In contrast, the effect of adrenalectomy on body weight was similar to all ages studied. When hydrocortisone (50 microgram/g BW) was administered to intact animals on day 15 or 16, it caused significant elevation of sucrase activity but, when administered on day 17, 18, or 28, there was no difference between control and treated animals. Since adrenalectomy on day 15 delayed weaning, it was possible that the glucocorticoid dependence of the younger animals was mediated by effects on feeding behavior. However, a further study showed that complete prevention of weaning did not depress sucrase activity between days 15--21. Thus, at early ages, when the tissue was sensitive to glucocorticoid, it was independent of dietary regulation. In contrast, at later ages (days 25 and 27), prevention of weaning caused significant depression of jejunal sucrase activity.
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PMID:Delineation of the glucocorticoid-sensitive period of intestinal development in the rat. 43 55

Lactase deficiency, manifested clinically by lactose malabsorption, is often the only biochemical evidence of a residual disturbance of jejunal mucosal function after Escherichia coli enteropathy in the infant. Villous morphology is usually normal. A sustained depression of the processes of biochemical differentiation of lactase biosynthesis has been postulated to explain similar states of lactase deficiency, but a possible influence of altered epithelial cell turnover on the mucosal lactase levels has not been investigated. In ten infants with a residual lactose malabsorption, after E. coli infection, jejunal cell renewal activity and disaccharidase activities were studied by analysis of the exfoliated cells collected by lumenal perfusion. Significant increases in DNA and protein exfoliation and in the brush border activities of sucrase and lactase were observed during recovery from the malabsorptive disturbance. DNA and protein efflux increased almost linearly during a 20-day period. Lactase was initially four times more deficient than sucrase activity in the exfoliated cells. Both enzyme activities increased at almost identical rates. Therefore, it took longer for lactase activity to return to normal levels. The lactase/sucrase ratios approached normal at the end of the 20-day period. The changes in the exfoliating levels of the two enzymes, when analysed in relation to the increases in cell renewal activity, suggested a relationship between sucrase and lactase levels and cell age.
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PMID:Intestinal exfoliated cells in infant diarrhoea: changes in cell renewal and disaccharidase activities. 104 54

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

In suckling rats prematurely weaned on the 15th, 17th, 19th or 21st day of life, the body weight and the weight of small intestine were studied as well as the activity of enteral sucrase and lactase. A delay in the gain of body weight and small intestine weight was the greater the earlier the sucklings had been weaned. The sucrase activity did not depend on the term of weaning. Whereas weaning on the 15th or 17th days of life considerably delayed the decrease in lactase activity. The latter seems to be due to the changes in the suckling's thyroid state because of thyroid depression under these conditions and absence of thyroid hormones intake from maternal milk.
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PMID:[Changes in the saccharase and lactase activities of the small intestine in suckling rats prematurely weaned from the nursing dam]. 133 Jul 17

To identify new genes required for depression of the SUC2 (invertase) gene in Saccharomyces cerevisiae, we have isolated mutants with defects in raffinose utilization. In addition to mutations in SUC2 and previously identified SNF genes, we recovered recessive mutations that define four new complementation groups, designated snf7 through snf10. These mutations cause defects in the derepression of SUC2 in response to glucose limitation. We also recovered five alleles of gal11 and showed that a gal11 null mutation decreases SUC2 expression to 30% of the wild-type level. Finally, one of the mutants carries a grr1 allele that converts SUC2 from a glucose-inducible gene.
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PMID:New SNF genes, GAL11 and GRR1 affect SUC2 expression in Saccharomyces cerevisiae. 175 13

Oral administration of the antiulcerogenic drug, cimetidine, was studied on kidney-bound hydrolytic enzymes at three different dose levels (30 mg, 100 mg, and 2000 mg/kg body weight) and for single administration for 2 and 24 h, and daily administration for 15 days in mice. It significantly inhibited Na+, K(+)-ATPase, Mg(2+)-ATPase, and Ca2+, Mg(2+)-ATPase in the isolated basolateral membrane (BLM). Brush-border-membrane-(BBM)-associated enzymes, sucrase, lactase, maltase, leucine aminopeptidase, and alkaline phosphatase also showed a marked reduction. Substrate saturation kinetics revealed the nature of inhibition was of mixed type in the case of sucrase, lactase, maltase, and alkaline phosphatase (Km was increased, while Vmax decreased), whereas it was of non-competitive type for leucine aminopeptidase (Km was unchanged, while Vmax decreased). In vitro addition of cimetidine (5-20 mM) to the BBM also inhibited the enzyme activity. Dixon plot produced the inhibition constant (Ki) for cimetidine in the case of maltase, alkaline phosphatase, and leucine aminopeptidase in the order of 14.83, 32.83 and 11.5 mM, respectively. Analysis of lipids revealed a significant reduction in BBM-associated phospholipid and phospholipid/cholesterol molar ratio, while the neutral lipid fraction, i.e., cholesterol and triglycerides were not altered. Free fatty acid exhibited an increase after drug treatment, which was significant at higher dose after 24 h of single and 15 days of daily treatment. BLM-associated lipids did not exhibit any significant change. Cimetidine-induced depression in renal BLM- and BBM-associated disaccharidases and ATPases, at least at the higher dose level, may have serious consequences in the absorption of end-product nutrients.
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PMID:Depression of membrane-bound hydrolases by cimetidine in mouse renal basolateral and brush border. 183 34

There was a significant depression of the activities of intestinal lactase, invertase, and alkaline phosphatase in rats given drinking water containing 2.5 mg of colchicine per 100 ml. Activities of intestinal maltase, aspartate transcarbamylase, and dihydroorotase were not affected by the drug. Injection of colchicine (1 mg/kg) caused depression of intestinal invertase activity within 8 hr. Investigation of the effect of colchicine on the disaccharides in vitro demonstrated that invertase and maltase were not affected by concentrations up to 125 mg/100 ml. Intestinal lactase was inhibited by concentrations exceeding 5 mg/100 ml. Calculation of the concentration of colchicine present in the intestine, after a single injection, indicated that the in vivo effect of colchicine was not due to simple enzyme inhibition. Histological examination showed an increase in crypt cells but no decrease in the length of the villi. Cellular migration along the villi, as well as activity of uridine kinase in intestinal mucosa, was increased in colchicine-treated rats. It was concluded that colchicine did not depress intestinal invertase, lactase, and alkaline phosphatase by decreasing cellular renewal, but rather it exerted its effect directly on the differentiated cells of the villus.
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PMID:Effect of colchicine on intestinal disaccharidases: correlation with biochemical aspects of cellular renewal. 541 79

The antinutritional effect caused by the ingestion of lectins from two Brazilian varieties of beans: Rico 23 and Jalo, was studied in rats. The two varieties were selected in a previous screening of toxicity in rats: one of them (Jalo) was lethal, and the other (Rico 23) was not, when injected intra-peritoneally. Different amounts of each one of the lectins were added to casein experimental diets and fed to rats. The amount of protein (casein) also varied from 5% to 20%. The addition to the diet of 1% lectins from the Jalo variety caused a growth depression, as well as a decrease in food efficiency ratio and serum glucose; also, it reduced the maltase and invertase activity of the intestinal mucosa. All these effects appeared when the protein contents in the rations were 5% or 10%. At the 20% level only a depression of the maltase activity was observed. Similar effects were shown by the lectins of the Rico 23 variety, but only when added in a higher (5%) percentage to the diet. The phosphatase and protease activity were not changed by any of the lectins. The inhibitor activity that occurred in vivo was not detected in vitro.
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PMID:[Antinutritional effect of phytohemagglutinins of Phaseolus vulgaris L]. 639 38


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