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 morphological maturation and the distribution of brush border hydrolase activities were studied in the small intestine and the colon in newborn babies of 28-38 weeks gestational age. Lactase and sucrase activities were higher at term with maximal activity in the proximal intestine. In contrast, aminopeptidase and glucoamylase exhibited maximum activity in the distal part of the small bowel. Glucoamylase activity was already significant in the small intestine and in the colon of the preterm newborn. Sucrase activity present in the proximal colon of the preterm dropped to a negligible amount at term, whereas aminopeptidase activity increased, reaching values found in the small intestine. The enzymic changes occurring in the intestinal tract were related to the morphological maturation of the mucosa from fetal to adult type during late gestation. Accelerated morphological and functional maturation was observed in one preterm infant nourished intravenously for 12 days, these processes being independent of the presence of nutrients in the intestine. At term, the distal part of the intestine seems to have increased digestive capacities for peptides and polysaccharides. We present evidence that full-term, and to a lesser extent preterm infants are able to hydrolyse glucose polymers.
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PMID:Longitudinal distribution of brush border hydrolases and morphological maturation in the intestine of the preterm infant. 308 71

Full-value diets of similar composition were given to male rats weighing 207-230 g, by intravenous (group 1) or intragastric (group 2) routes. The proportion of amino acids, fats and carbohydrates was 9.9:15.7:74.4 (with regard to their calorific value). The diet calorific value comprised 60.6 kcal/rat/day. An average mass increase in group 1 was 2.44 +/- 0.14 g/day, in group 2 - 1.75 +/- 0.11 g/day. The protein content and activities of alpha- and gamma-amylase, invertase, maltase, and glycil-L-leucine dipeptidase were assayed in the intestinal mucosa of the proximal portion of the small intestine in group 1 rats, while a decreased alpha-amylase activity in the distal portion of the small intestine was recorded in the animals of group 2. The mass of the pancreas in the rats of group 1 and 2 was authentically lower than in the control rats which received oral feeding with natural foods. The lowest mass of the pancreas was observed in the rats of group 1. Specific activity of trypsin, lipase and RNase in the pancreatic tissues of rats in groups 1 and 2 was similar. The results of the study have evidenced a lowered function of the digestive system under conditions of artificial feeding, especially in case of intravenous nutrition.
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PMID:[Digestive function of the small intestine and pancreas in rats on artificial feeding]. 309 Jul 82

Intestinal hydrolase activities were studied during postnatal development in the offspring of rats exposed to 20% ethanol during gestation; alcohol was withdrawn at birth. Controls received water during gestation. Sucrase, lactase, glucoamylase and aminopeptidase activities were determined 2 and 4 weeks after birth in the proximal jejunum. Offspring prenatally exposed to ethanol showed a deficit in body weight and lower aminopeptidase activity during the suckling period (2 weeks). These effects were reversible by 4 weeks when alcohol was withdrawn at birth. The prenatal exposure to ethanol did not change the pattern of sucrase maturation in the intestine of offsprings. The activities of lactase and glucoamylase were not modified following prenatal exposure to ethanol. In conclusion, exposure to ethanol during gestation caused decreased abilities for the intestine of the offspring to digest protein.
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PMID:Prenatal exposure to alcohol in rat: effect on intestinal enzymes in offspring. 311 99

Studies of intestinal enzyme development and regulation relevant to the human infant require an animal model with a rate of maturation similar to that of the human infant. Hanford miniature pigs were weaned at 3 days of age to a standard swine weaning formula. At 1, 2, 3, 4, 5, and 6 wk of age, duodenal jejunal, and ileal segments were analyzed for protein content and lactase, sucrase, maltase, glucoamylase, and acid beta-galactosidase activities. Protein content of the small intestine changed significantly with age only in the ileum (p less than 0.05). Lactase activity fell significantly with age in all segments of the small intestine (p less than 0.001); activity was highest in the jejunum. Sucrase and maltase activities were present in all segments of the small intestine at 1 wk of age. Sucrase increased significantly (2-fold, p less than 0.02) with age only in the ileum and maltase increased significantly with age in the jejunum (by 50%, p less than 0.05) and the ileum (3-fold, p less than 0.001). Activities were highest in the jejunum. Glucoamylase activity was present at 1 wk of age and showed a small but significant increase with age only in the duodenum (p less than 0.005). Acid beta-galactosidase activity demonstrated small but significant decreases with age in all small intestinal segments. Glucoamylase and acid beta-galactosidase activities were similar in all segments. In the 6-wk-old pigs, activities of all the enzymes tested were similar to those found in young human infants.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The miniature pig as an animal model for the study of intestinal enzyme development. 312 4

1. The intestinal disaccharidase activities of a suckling crabeater seal were investigated. 2. Lactase, maltase, isomaltase and cellobiase activities were readily detected but trehalase and sucrase activities were absent. 3. The intestinal homogenates were separated into a soluble (S2) fraction and a particulate brush border (P2) fraction. The lactase activities of the two fractions had different properties corresponding to those of an acid and a neutral beta-galactosidase respectively. Approximately two-thirds of the total lactase activity measured at pH 6.0 was due to the acid beta-galactosidase. 4. The isomaltase and cellobiase activities were found almost exclusively in the particulate fractions but about one third of the maltase activity was in the S2 fraction. This soluble maltase activity appeared to be due to an acid maltase.
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PMID:Intestinal lactase and other disaccharidase activities of a suckling crabeater seal (Lobodon carcinophagus). 313 70

The influence of epidermal growth factor (EGF) on the differentiation and proliferation of human fetal jejunum was studied in organ cultures. Fetal intestine (11-14-wk gestation) was cultured for 5 days at 37 degrees C in serum-free Leibovitz L-15 medium alone or supplemented with 25, 50, and 100 ng EGF/ml culture medium. The addition of hormone did not modify the morphology of the intestinal explants. Biochemical studies revealed that lactase activity was significantly increased with the addition of 50 and 100 ng EGF/ml culture medium. On the other hand, the increase in sucrase, trehalase, and glucoamylase activities that normally occurs during the culture was repressed in the presence of increasing concentrations of EGF. Deoxyribonucleic acid synthesis was significantly decreased after 5 days of culture even in the presence of the lowest EGF concentration used. Concomitantly, the labeling index of the epithelial cells dropped drastically in the presence of EGF. The EGF-induced variation in DNA synthesis was already evident within 24 h of culture, whereas enzymic modifications occurred only between the third and fifth day of culture. The simultaneous addition of EGF and hydrocortisone (50 ng/ml) did not reveal any synergistic action between the two hormones on the hydrolytic activities of the brush border. However, EGF did inhibit hydrocortisone-stimulated DNA synthesis. The present work provides for the first time some basic data on the influence of EGF on brush border hydrolytic activities and on epithelial cell proliferation of human fetal jejunum. These observations strongly suggest that EGF plays an important role in the fetal development of the human gastrointestinal tract.
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PMID:Biologic effects of epidermal growth factor in human fetal jejunum. 325 52

MDL 25,637 is a novel compound designed as a transition-state inhibitor of alpha-glucohydrolases. This compound inhibits rat intestinal sucrase, maltase, isomaltase, glucoamylase and trehalase activities at micromolar concentrations. It is a much weaker inhibitor of alpha-amylase and lactase. Inhibition of sucrase was competitive with sucrose. In mice, MDL 25,637 inhibited the rise in serum glucose after a sucrose or starch load but not after a glucose load. MDL 25,637 also reduced the glycemic response to sucrose in rats. The drug was most effective when administered 0 to 30 min before the sucrose load and was as effective in streptozotocin-treated rats as in normals. The inhibition by MDL 25,637 of intestinal glucohydrolases is an effective means of reducing the hyperglycemic response to an oral sucrose or starch load and, as such, warrants further investigation as a potential drug for the treatment of diabetes mellitus.
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PMID:Inhibition of intestinal disaccharidases and suppression of blood glucose by a new alpha-glucohydrolase inhibitor--MDL 25,637. 329 22

The direct influence of epidermal growth factor (EGF) on the differentiation and proliferation of small intestine was studied in organ culture. Eight-day-old mouse small intestine was cultured during 2 days in serum-free Leibovitz L-15 medium alone or supplemented with EGF (50, 100, and 500 ng/ml) either at room temperature or at 37 degrees C. Brush border membrane hydrolytic activities, namely, sucrase, lactase, glucoamylase, trehalase, maltase, and alkaline phosphatase, were assayed in the intestinal tissue as well as in the culture medium. None of the brush border enzymic activities was affected by the addition of EGF to the culture medium. This lack of effect is not temperature dependent since it occurred both at room temperature and at 37 degrees C. The addition of hydrocortisone (10(-6) M) to the culture medium induced the appearance of sucrase activity and increased the activity of the other brush border enzymes. The simultaneous addition of EGF with hydrocortisone did not influence the response of the intestinal explants to hydrocortisone. The deoxyribonucleic acid (DNA) content was determined while DNA synthesis was evaluated by the incorporation of (3H)-thymidine. The addition of EGF did not affect DNA content or (3H)-thymidine incorporation into DNA either at room temperature or at 37 degrees C. The EGF binding to epithelial cells did not significantly vary throughout the culture period and a down-regulation process occurred in presence of EGF. These observations strongly suggest that EGF does not act as a primary cue for inducing developmental changes in suckling mouse small intestine. It is proposed that EGF induces a systemic reaction in vivo that then influences the neonatal small intestine.
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PMID:Epidermal growth factor does not act as a primary cue for inducing developmental changes in suckling mouse jejunum. 349 91

Human fetal colon (14-16 weeks gestation) was cultured as explants for 15 days in serum-free Leibovitz L-15 medium at 37 degrees C. The overall morphology of the colonic explants was well maintained throughout the culture period and all epithelial cell types retained their ultrastructural characteristics. The incorporation of [3H]-leucine continued and even increased, reflecting sustained synthesis of proteins. Even though the incorporation of [3H]-thymidine into the total DNA decreased during culture, the synthesis of DNA continued. The sites of [3H]-thymidine incorporation into the different layers of the colonic wall were studied by radioautography. The incorporation of the radioactive precursor occurs mainly in the epithelium and to lesser degrees in the mesenchyme and the muscular layer. Labeled epithelial nuclei were located in the intervillous areas but not on the villi. The labeling index of the epithelial cells remained constant throughout the culture period indicating the preservation of the proliferative capacity of the epithelium. Brush-border hydrolytic activities, namely those of sucrase, maltase, lactase, trehalase, glucoamylase and alkaline phosphatase, were assayed in the colonic tissue. These enzymic activities generally decreased in the tissue and increased in the medium during the course of culture. These observations clearly demonstrate that fetal colon can be maintained viable for at least 15 days in a serum-free medium. Organ culture now provides the opportunity to study the normal function and metabolism of human colon during its development.
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PMID:Human fetal colon in organ culture. 368 52

For 1 wk, 3-mo-old male rats were fed a low-starch (5 cal%), high-fat (73 cal%, corn oil) diet followed by a high-glucose-polymer (70 cal%), low-fat (7 cal%, corn oil) or a middle-glucose-polymer (40 cal%), middle-fat (37 cal%, corn oil) diet. Other animals were fed similar diets but with starch or sucrose instead of the glucose polymers. Rats were sacrificed 2 or 7 days later. Food intake, body weight changes, and protein content per intestinal segment were similar in all groups. Increased carbohydrate intake evoked an increase of sucrase, maltase, glucoamylase, and lactase activity in both the jejunum and ileum. Effect of glucose polymers on glucohydrolase was similar in animals fed commercial liquid-soy-based infant formulas containing sucrose, glucose polymers, or both. Results support using glucose polymers as replacements for sucrose or starch when digestion impairment of those sugars is suspected or when a formula of lower osmolality is indicated.
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PMID:Dietary regulation of intestinal glucohydrolases in adult rats: comparison of the effect of solid and liquid diets containing glucose polymers, starch, or sucrose. 371 63


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