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)

In the intestinal epithelium the rapidly proliferating crypt cells, the precursors of the mature enterocytes are extremely sensitive to the effects of cytostatic agents. The symptoms of intestinal impairment: nausea, vomiting, diarrhea, ulceration, are well known both in clinical practice and in experimental chemotherapy. To obtain information about the biochemical nature of these side effects, a study was performed by investigating the influence of clinically used alkylating hexitol derivatives, dianhydrogalactitol and diacetyl-dianhydrogalactitol, on rat intestinal mucosa cells. The biochemical parameters were investigated in isolated intestinal mucosa cells. Cell proliferation was characterized by measuring the activity of thymidine kinase, while digestion was evaluated by assaying the alkaline phosphatase, sucrase and maltase activities localized in the brush border membrane of the villus cells. The dose response studies of the different enzyme activities indicated that inhibition in all cases was dose dependent. The nadir of the intestinal damage and the time of regeneration were influenced both by the dose and the dosage schedule of the drugs.
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PMID:Biochemical changes of intestinal epithelial cells induced by cytostatic agents in rats. 386 86

In this paper, we analyze the factors involved in the precocious increase of sucrase activity evoked by the early feeding of sucrose in suckling rats, and particularly, the role of diarrhea and stress in this phenomenon. Ten-day-old rats were removed from their mothers and gavage fed for 4 days at 3-h intervals either a basic low carbohydrate milk formula (10.8% fat, 8% protein, 1.4% carbohydrate; all by weight/volume) or basic low carbohydrate milk with: lactose (13%), fructose (13%), or Polycose (2%, 6%, or 13%); all formulas were isocaloric. Feeding the formula containing fructose or high (13%) Polycose led to diarrhea and evoked a concurrent increase of small intestinal sucrase activity. In further experiments, 11-day-old rats were fed the basic formula, the lactose (13%), the fructose (13%), and a sucrose (13%) formula for 8 h between 2 a.m. and 10 a.m. Also, 10-day-old rats were fed 0.5 ml of a solution of 5% mannitol in water while nursing with their mothers. The serum corticosterone levels were substantially increased within 8 h after the initiation of feedings with sucrose and fructose milks and the mannitol solution. The mannitol-fed rats also developed diarrhea within a day in association with a marked increase in sucrase activity. We conclude that a precocious increase of sucrase activity in the small intestine of suckling rats by dietary sugars is not caused by substrate induction, but is mainly due to the effect of stress. The stress is caused by diarrhea which is evoked by the feeding of indigestible and/or unabsorbable amounts of sugar.
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PMID:Precocious increase of sucrase activity by carbohydrates in the small intestine of suckling rats. I. Significance of the stress effect of sugar-induced diarrhea. 404 May 66

The activities of intestinal sucrase and isomaltase are not detectable in rats before 15-16 days of age, but administration of corticosteroids precociously induces the activities of these two alpha-glucosidases. 9-day old rats were removed from their mothers, warmed in an incubator, and fed by constant infusion through gastrostomies. The basic diet was a soya preparation to which various sugars were added. When the diet contained 2% sucrose, diarrhea ensued for 48 hr, but subsided when intestinal sucrase and isomaltase appeared precociously. In animals fed sucrose, the activities of sucrase and isomaltase were markedly increased as compared to animals on carbohydrate-free diets (sucrase 2.41+/-0.23 vs. 0.63+/-0.13 U, isomaltase 3.43+/-0.42 vs. 0.78+/-0.18 U). Maltase activity was doubled, while lactase was not altered significantly. The mitotic index of crypt cells, the depth of crypts, and incorporation of thymidine-(3)H into DNA were increased. In adrenalectomized rats, activities of sucrase and isomaltase were not detected nor induced by sucrose. Steroids given to adrenalectomized rats caused appearance of the enzymes; but if cortisone and sucrose were given together, there was synergism evidenced by a marked increase in activities (sucrase 7.2+/-1.1 vs. 0.68+/-0.12 U). In contrast to observations in adult animals, the effect of sucrose on alpha-glucosidases in developing animals demands the participation of the adrenal gland.
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PMID:Effect of carbohydrate and corticosteroids on activity of -glucosidases in intestine of the infant rat. 505 29

Diarrhoea is a common sequel to vagotomy and pyloroplasty but its cause is unknown. One of our patients who developed this complication had an abnormal lactose barium meal and responded well to a lactose-free diet. This led us to make a systematic study of disaccharidase activity in the small intestine in patients with diarrhoea following vagotomy and pyloroplasty. The small-intestinal disaccharidases have been estimated in jejunal biopsy specimens taken from 23 patients suffering from persistent diarrhoea, either continuous or episodic, after vagotomy and pyloroplasty. The disaccharidase values were normal in all but one of these patients. This patient showed hypolactasia but the sucrase and maltase levels were normal. The jejunal biopsy specimen taken from this patient showed a convoluted pattern under the dissecting microscope and severe partial villous atrophy under the light microscope. A repeat jejunal biopsy taken 20 cm beyond the duodeno-jejunal flexure showed similar appearances and also had a low level of lactase. However, two lactose tolerance tests and a lactose barium meal yielded normal results, suggesting that the low level of lactase in the upper jejunum was not a limiting factor in lactose absorption. The finding of one example of a low lactase level among 23 postvagotomy patients corresponds with what is being found in a study of normal subjects at present in progress. In effect, almost all patients with persistent diarrhoea after vagotomy and pyloroplasty have normal small-intestinal disaccharidase activity.
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PMID:Disaccharidase levels in the small intestine in patients with diarrhoea following vagotomy and pyloroplasty. 554 54

In order to clarify the mechanism of the adverse effects of air-oxidized oil feeding, the effects of dietary soy bean oil on body weight gain, food consumption, fecal consistency and gastrointestinal functions were investigated in rats. Feeding of oxidized soy bean oil with a peroxide value above 350 produced significant reductions in body weight gain, food consumption and intestinal sucrase activity, and severe diarrhea. These adverse effects were prevented with the concurrent feeding of Gobo dietary fiber and were rapidly eliminated within a day after switching to the diet containing the unoxidized soy bean oil. Furthermore, the remarkable release of sucrase from the small intestine was observed on perfusion of the jejunum with Ringer's bicarbonate solution containing the oxidized soy bean oil at the 1% level. These findings suggest that the adverse effects occurring after air-oxidized oil feeding are due to a disturbance of gastrointestinal functions, and raise the possibility that the primary cause might be solubilization or exfoliation of the brush border membrane.
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PMID:Mechanisms of adverse effect of air-oxidized soy bean oil-feeding in rats. 608 37

Infants undergoing phototherapy may develop loose stools. Acquired lactase deficiency secondary to this treatment modality was suggested as a cause for the diarrhea. The effects of light energy directly on intestinal enzymes and indirectly through bilirubin photooxidation products were studied. Adult homozygote and heterozygote Gunn rats were treated with light for varying periods while littermate controls were kept in the dark. Intestinal lactase, sucrase and GGTP activities and serum bilirubin concentrations were determined. Jaundiced and non-jaundiced 1-week-old suckling Gunn rats were treated with light for 96 h, and intestinal lactase activity determined. No decreases in lactase, sucrase or GGTP activities were observed suggesting the reported diarrheal states following phototherapy are not related to light energy or photooxidation products.
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PMID:The effect of phototherapy on intestinal mucosal enzyme activity in the Gunn rat. 610 92

A 7-year-old girl suffering from chronic diarrhoea due to sucrase deficiency was referred because of poor hair growth. Her scalp hair had a poor, colourless appearance and was much thinned in the occipital region. Her skin was dry, but otherwise normal. P-zinc was low (7.9 mumol/l), whereas P-albumin was normal. Oral zinc therapy, 40 mg daily, had a marked beneficial effect on her scalp hair, eyebrows and eyelashes, which became thicker and pigmented. Beau lines appeared on thumb-nails and 4th left finger-nail. A rise in P-zinc and S-alkaline phosphatase levels was observed during the zinc supplementation. Microscopic examination of her poor scalp hair, using polarized light, revealed well-defined abnormalities of the hair shafts, as reported by others in a case of acrodermatitis enteropathica: 1) a marked individual variation in diameter, 2) narrowing often associated with waving or sharp bending and broken ends, 3) striation with a tendency to trichonodosis. Such changes were absent in the pigmented hair appearing after the start of zinc therapy.
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PMID:Hair changes due to zinc deficiency in a case of sucrose malabsorption. 617 38

Experiments were undertaken to investigate whether a hypersensitivity response to dietary antigen might be a predisposing factor in the aetiology of post weaning diarrhoea. The results indicated that: 1. very small amounts of food given to baby pigs before weaning significantly increased the severity and accelerated the onset of the disease; 2. post weaning diarrhoea was dependent upon the presence within the diet of antigenic material; 3. weaning diets containing little antigenic material had less effect upon sucrase levels in the brush borders than did diets rich in antigens. These results are discussed in relation to the hypothesis that immune mediated intestinal damage may predispose to post weaning diarrhoea.
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PMID:The role of dietary antigen in the aetiology of post weaning diarrhoea. 637 29

We report results on determinations of small intestinal brush-border enzyme activities in 22 children (aged 11 months to 14 years) with giardiasis. In particular, activities of disaccharidases (lactase, sucrase, maltase) and of alkaline phosphatase were investigated. Forty-one percent of the patients, irrespective of age, had a demonstrable depression of disaccharidase activities, usually in a combination involving two or more enzymes. A depression of intestinal alkaline phosphatase activity was present in 33% of patients, and only in those who demonstrated disaccharidase deficiencies. Mild villus atrophy was present in two mucosal specimens, whereas all others showed normal villus morphology by light microscopy. The results obtained in this study suggest that giardiasis in otherwise healthy children does not cause marked structural damage to the small bowel mucosa, as seen by the light microscope. However, some form of damage to the brush border does occur frequently, as evidenced by a depression of brush-border enzymes. This damage most likely contributes to the diarrhea and also to the carbohydrate intolerance in these patients.
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PMID:Intestinal disaccharidase and alkaline phosphatase activity in giardiasis. 642 May 34

Unsuspected bacterial contamination of the small intestine was indicated by breath hydrogen testing in nine patients aged 2 to 34 months during physical examinations for chronic diarrhea and abdominal pain. Elevated bacterial counts of questionable significance were found in duodenal aspirates before and after antibiotic treatment. There was no evidence of bile salt deconjugation or structural changes in the small intestine by light or electron microscopy. This may indicate that the site of colonization is distal to the biopsy site. Breath testing indicated lactose malabsorption in all patients, and four of five patients tested also malabsorbed sucrose. Duodenal disaccharidase levels in all patients were within the normal ranges, but in eight patients the lactase-sucrase ratio was greatly elevated (0.80 +/- 0.36; normal less than 0.45). Dietary restriction alone did not cause complete cessation of symptoms, whereas all patients responded dramatically to oral antibiotic therapy. When patients were well, the lactase-sucrase ratio had returned to normal in those tested, and all nine had normal lactose and lactulose breath hydrogen tests. Unsuspected bacterial contamination of the small intestine, which is easily detected using the breath hydrogen test, may be more commonly associated with chronic diarrhea in children than has been previously realized. In such cases, therapy should be directed at removing the contamination.
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PMID:Bacterial contamination of the small intestine as an important cause of chronic diarrhea and abdominal pain: diagnosis by breath hydrogen test. 643 89


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