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)

The biochemical background of the intestinal side effects of cis-diammine-1,1-cyclobutane dicarboxylate platinum (II) (CBDCA) and cis-diisopropylamine-trans-dihydroxy-dichloro platinum (IV) (CHIP) was compared with those of cis-diamminedichloroplatinum (II) (CDDP). Biochemical investigations were carried out on mucosal cells isolated by a combined chemical-mechanical method from the total length of the small intestine. After treatment with single, equitoxic doses of Pt analogues, the activities of thymidine kinase (TK) EC 2.7.1.21, sucrase (SUC) EC 3.2.1.26, maltase (MAL) EC 3.2.1.20, and protein content showed dose-dependent decreases, whereas the activity of alkaline phosphatase (AP) EC 3.2.1.20 increased slightly. The nadir of enzyme activity changes occurred 24-48 h after treatment. For the regeneration of the mucosa more than 96 h was necessary. Of the platinum analogues studied, CHIP proved to be the most toxic to the small intestine. While the highest doses of CDDP and CBDCA (0.66 x LD50) caused significant but less than 50% decreases in TK, SUC, MAL, and protein content (PROT), the CHIP doses needed for 50% reduction were between 0.44-0.66 x LD50.
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PMID:Comparison of intestinal toxic effects of platinum complexes: cisplatin (CDDP), carboplatin (CBDCA), and iproplatin (CHIP). 327 33

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

To investigate the effect of chronic protein-calorie malnutrition on intestinal repair after an enteric infection, we examined small intestinal structure, enzyme activity, and sodium transport in undernourished piglets during the acute and convalescent phases of a viral enteritis, transmissible gastroenteritis (TGE). Gnotobiotic pigs, nutritionally deprived from the age of 7 days, gained less weight than dietary controls from 14 days of age until the end of the study. Animals from malnourished and control diet groups were inoculated with TGE virus at 22-23 days and studied during the acute (40 h) and convalescent (4, 10, and 15 days) stages of this experimental enteritis along with noninfected dietary controls. After TGE infection, we observed a further decrease in weight gain and an increased mortality only in undernourished pigs. In jejunum and ileum of both dietary groups at 40 h after TGE infection, we observed comparable structural lesions, similar decreased activities of mucosal enzymes (sucrase, lactase, sodium-potassium-dependent ATPase), and increased thymidine kinase activities. Also we noted comparable diminution of glucose-stimulated jejunal sodium absorption in both dietary groups at 40 h. In control diet pigs, transport abnormalities recovered by 4 days after TGE infection and normal mucosal structure and enzyme activity returned over 4-15 days. In undernourished piglets, structural repair and enzyme abnormalities were prolonged when compared with the control diet group; glucose-stimulated sodium transport did not recover until 10 days after infection and never regained the enhanced activity seen in noninfected undernourished controls.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Impact of chronic protein-calorie malnutrition on small intestinal repair after acute viral enteritis: a study in gnotobiotic piglets. 392 24

To evaluate the effect of aging upon the small intestine, the distribution, content, and concentration of epithelial cell enzymes at different levels along the crypt-villus column were measured in aging and young adult, male, Fisher 344 rats. Specific activities of sucrase, maltase, lactase, and adenosine deaminase in mucosal homogenates were lower in the upper intestines of aging than in young animals, whereas the specific activity and content of thymidine kinase was higher. Enzyme activities were measured in cells obtained by cryostat sectioning from villus tip to crypt base. Sucrase and maltase activities were fully expressed nearest the crypt, alkaline phosphatase in cells higher on the villus, and adenosine deaminase higher still, whereas thymidine kinase activity was limited to the crypts. The ordered pattern of enzyme expression was maintained in aging rats but the initiation and duration were delayed. Because peak specific enzyme activities were similar in young and aging animals, the reduced specific activities in mucosal homogenates from aging animals were due to an increase in the proportion of relatively undifferentiated villus epithelial cells. These findings are of importance in explaining altered intestinal function during aging without a concomitant change in intestinal structure.
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PMID:Delayed enzyme expression: a defect of aging rat gut. 393 Mar 40

Wistar rats were treated with alkylating sugar alcohol derivatives, dianhydrogalactitol (DAG) and diacetyldyanhydrogalactitol (Diac-DAG), respectively. The drugs were intravenously administered as a single, bolus injection. The applied doses 2.5, 5, 10, 17 mg/kg DAG and 5, 10, 20, 40 mg/kg Diac-DAG were roughly equitoxic. The effect of these cytostatic agents was studied on the different marker enzymes (thymidine kinase, xanthine oxidase, alkaline phosphatase, sucrase, maltase) of the separated mucosa cells derived from the functional and proliferating zone of the small intestine. Both DAG and Diac-DAG inhibited the enzyme activities of the proliferating and mature enterocytes in a dose dependent fashion, primarily acting on the crypt specific thymidine kinase. The time dependent sequence in the biochemical alterations correlated well with the cytomorphological changes. The drug-induced damage was most pronounced 48 hours after a single treatment. The regeneration of the intestinal mucosa began on days 3 and 4 and was completed by day 7. Diac-DAG at equimolar concentration proved to be more toxic than DAG on the intestine as judged by the significantly higher decrease of protein content and xanthine oxidase activity.
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PMID:Enzymological and morphological changes in rat intestinal mucosa following treatment with alkylating sugar alcohol derivatives. 403 42

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

Epithelial cells of the rat small intestine were collected as a gradient of villus to crypt cells. Homogenates of these cells incubated with GDP-D-[14C]mannose in the presence of MnCl2 incorporated radioactivity into dolichyl mannosyl phosphate and a mixutre of dolichyl pyrophosphate oligosaccharides varying in the size of their oligosaccharide moiety. The labeled oligosaccharides formed in villus cell homogenates appeared shorter than those formed in crypt cell homogenates. The addition of dolichyl phosphate greatly stimulated the synthesis of dolichyl mannosyl phosphate. The initial rate of synthesis of dolichyl mannosyl phosphate from GDP-D-[14C]mannose and exogenous dolichyl phosphate was highest in an intermediate cell fraction having a low specific activity of sucrase and alkaline phosphatase and an intermediate specific activity of thymidine kinase. To compare the rates of dolichyl mannosyl phosphate synthesis in the different cell fractions, it was essential to control degradation of GDP-D-[14]mannose by the addition of AMP to the incubation, since villus cells degraded GDP-D-[14C]mannose much faster than crypt cells.
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PMID:Glycoprotein biosynthesis in intestinal epithelial cells during differentiation. Incorporation of [14C]mannose from GDP-[14C]mannose into dolichol derivatives. 615 73

The influence of the treatment schedule of dianhydrogalactitol on its effect on the activity of mucosal enzymes in rat intestine was studied. The effect of a single high dose (10 mg/kg) was compared with that of repeated small doses (4 x 2.5 mg/kg) given at daily intervals. At 48 h after a single high dose the activities of thymidine kinase, which is a marker of dividing crypt cells, and of alkaline phosphatase, sucrase, maltase, xanthine oxidase, which are markers of mature enterocytes, were strongly depressed. Even 96 h after the treatment low enzyme activities could be observed. Repeated small doses caused milder enzyme inhibition and almost total recovery had occurred by 96 h after administration of the last dose. The results indicate that fractionation of drug administration can reduce the toxic side-effects on the intestinal mucosa and might be partly responsible for the higher therapeutic index of such schedules in experimental tumor models.
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PMID:Effect of a single high dose and repeated small doses of dianhydrogalactitol (DAG; NSC-132313) on rat intestinal mucosa. 641 95

The effect of resuming food intake after a period of starvation (refeeding) on the specific activities of selected rat intestinal enzymes was determined. The rate of weight gain was higher in refed animals than in control animals, without a difference in food intake. Fasting caused intestinal atrophy which reversed rapidly on refeeding. Fasting decreased the specific activities of sucrase, maltase, and galactokinase, but did not affect the specific activities of hexokinase, pyruvate kinase, or crypt thymidine kinase. Sucrase, maltase, hexokinase, pyruvate kinase, and thymidine kinase specific activities all rose above control values during refeeding. The overshoot in intestinal enzyme specific activities may help promote the rapid weight gain observed in refed rats and is an integral part of the total adaptation to fasting and refeeding.
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PMID:Refeeding after a fast in rats: effects on small intestinal enzymes. 705 2

The effect of oral intake and body weight on postnatal maturation of the small intestine was examined in infant rabbits with accelerated weight gain. Intestine from immature animals is characterized by large unidirectional Na fluxes, failure of Na absorption to respond to glucose but increased ability to absorb monosaccharides, and an enzyme pattern of high lactase and thymidine kinase and low sucrase. Postnatal development was monitored by measuring Na and glucose transport in short-circuited jejunum and enzyme activities in jejunal mucosa. Accelerated weight gain was achieved in the experimental group by reducing litter size to 3 animals at 24-48 hours of age. Under glucose-free conditions unidirectional Na fluxes were significantly smaller in tissue from the heavier experimental animals compared to controls. The addition of glucose had no effect on Na fluxes in control tissue but significantly increased Na absorption in the experimental group. Unidirectional and net fluxes of 14C-D-glucose were significantly smaller in the heavy experimental animals compared to controls. Isolated villus enterocytes from the experimental group had reduced lactase and thymidine kinase activities. Sucrase activity, which did not differ in isolated cells, was increased in total mucosa from the experimental group. Solute transport and the enzyme profile in jejunum from the heavier experimental suckling rabbits is characteristic of intestinal epithelium from more mature animals, indicating accelerated postnatal maturation. The findings suggest that oral nutrient intake and body weight, rather than chronologic age, act as the physiologic trigger for postnatal maturation of the small intestine.
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PMID:Effect of body weight on postnatal development of the proximal small intestine of the rabbit. 713 89


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