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 activities of amylase, total proteases, monoglyceride lipase, glycyl-leucine dipeptidase and sucrase were investigated in mucosa from five consecutive parts of small intestine in blue fox, mink, ferret and rat. In comparison with rats, the activity gradient of carbohydrates and TPA in mucosa of predatory animals was shifted in the distal direction. The distribution of dipeptidase and monoglyceride lipase along the intestine was similar enough in all animals: the first was exemplarily the same all along the gut, while the second slightly decreased in a distal direction.
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PMID:Distribution of digestive enzyme activities along intestine in blue fox, mink, ferret and rat. 755 36

The present study was designed to investigate the effects of grape seed tannins on rat intestinal alkaline phosphatase (AP), sucrase and dipeptidyl peptidase IV (DPP IV) activities. An experiment was performed in vivo by dietary supplementation with 2% tannins; this diet was tested on an experimental group of rats; a control group received a diet without tannins. After 31 days, tannins intake significantly decreased middle-jejunal AP from 123 to 45 mU/mg protein and sucrase activities from 310 to 195 mU/mg protein, while no significant difference appeared at the duodenal stage (p < 0.05). Ileal DPP IV activity was also significantly reduced (p < 0.05) from 190 to 110 mU/mg protein after tannin intake. Using in vitro experiments on purified brush border membranes, AP activity was found to be inhibited by grape tannins; this inhibition was prevented by the detergent Triton X-100. The addition of pancreatic-biliary (PB) juice to the incubation medium prevented or reversed the tannin-inhibited enzyme activity. The present data indicate that in the duodenal lumen, alkalinity and detergency from the PB secretion neutralized the ability of tannins to inactivate brush border hydrolase activities and suggest that enzyme inhibition took place once bile salts were reabsorbed while moving down the gut. This was confirmed by in vitro experiments where sucrase and DPP IV activities inhibited by grape seed tannins were largely recovered after the addition of PB juice to the incubation medium.
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PMID:Effect of grape seed tannins on the activity of some rat intestinal enzyme activities. 778 71

When used as treatment for hypercholesterolemia HMG-CoA reductase inhibitors will first pass through and act upon the gut mucosa. Although cholesterol availability is essential for cell growth of the intestinal mucosa adverse intestinal events are rare which is possibly due to hitherto undefined compensatory mechanisms. In the present work we therefore studied the long-term influence of mevinolin on proliferation and differentiation of CaCo-2 cells as an enterocyte model and their response upon the cholesterol supply of different origin. Mevinolin caused a marked and dose-dependent inhibition of cell proliferation, microvilli length and alkaline phosphatase. This parallel suppression was reversed by the addition of either exogenous free cholesterol, endogenous cholesterol from mevalonolactone or LDL but not HDL3. Surprisingly, sucrase activity reacted in an inverse fashion to alkaline phosphatase activity. Mevinolin induced enzyme activity and this was further enhanced by mevalonolactone supply, while cholesterol and LDL normalized sucrase to controls. In conclusion, the presence of luminal cholesterol as well as plasma LDL as the cholesterol source for the enterocyte may prevent mevinolin toxicity.
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PMID:Influence of cholesterol supply on cell growth and differentiation in cultured enterocytes (CaCo-2). 789 34

The proliferative activity of gut mucosa is altered with aging; the potential for the aged gut to respond to trophic stimuli is not known. The purpose of this study was to determine whether there are age-related differences in the effects of the trophic gut peptide neurotensin (NT) on the structure and function of small bowel mucosa. NT (300 micrograms/kg) or saline (control) was injected subcutaneously at 8-h intervals for 5 days in rats of two age groups, young (2 mo) and aged (24 mo). On day 6, rats were killed, and the gut mucosa (proximal and distal small bowel) was scraped, weighed, and analyzed for DNA, RNA, and protein content and for disaccharidase (sucrase and maltase) activity. In a second experiment, the groups of rats and the protocol for NT administration were identical; however, when the rats were killed, the distal gut was removed for histological evaluation of crypt and villus length (mm) and density (no./cm gut segment) and bromodeoxyuridine immunohistochemistry. NT produced significant increases in mucosal growth (wt, DNA, RNA, and protein) in both age groups when compared with age-matched controls; the increase of growth measurements was the greatest in the small bowel mucosa of the aged rats. In addition, NT increased crypt density in both groups; only the aged group treated with NT demonstrated increases in crypt depth and villus height. Specific activities of sucrase and maltase did not change with NT treatment in either of the age groups. We conclude that the proliferative potential of small bowel mucosa is maintained with aging in response to administration of NT.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effect of aging on neurotensin-stimulated growth of rat small intestine. 807 18

Gas chromatography (GC) analysis of 159 specimens (144 females and 15 males) of Lutzomyia youngi collected in Shannon traps in a coffee plantation in the Andean region of western Venezuela, where leishmaniasis is endemic, revealed the presence of fructose, sucrose, glucose and maltose in the gut and crop of the wild sandflies. The identification of the sugars was confirmed by comparing retention times with those observed for standard sugars and those obtained from sandflies experimentally fed on known sugar solutions. Although the sandflies in nature may ingest each of the four sugars, the results suggest that it is more probable there is an invertase enzyme (glycosidase?) in the gut or crop of the sandfly which hydrolyses ingested disaccharides (e.g. sucrose) to the constituent monosaccharides (i.e. fructose and glucose). Ecological and altitudinal distributions of sandfly species may be related to the availability of specific sugar sources, with epidemiological implications. Identification of the preferred sugar could make breeding easier and would facilitate further research on Leishmania-vector relationships.
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PMID:Sugars in the alimentary canal of Lutzomyia youngi (Diptera: phlebotominae). 816 42

Human immunodeficiency virus (HIV)-associated intestinal abnormalities can occur before immunodeficiency or infection with opportunistic enteropathogens. Rhesus macaques infected with simian immunodeficiency virus (SIV) develop an AIDS-like illness that frequently includes enteropathy. The development of enteropathy and its association with SIV infection in the intestinal tract was examined. By 1 week after infection, SIV-infected macrophages and T lymphocytes were detected in gut-associated lymphoid tissue. In contrast to findings in the asymptomatic stage, SIV-infected macrophages were numerous in primary and terminal stages of infection. An acute enteropathy syndrome was observed in the primary acute stage of infection. Functional abnormalities of absorptive epithelium, indicated by D-xylose malabsorption and decreased sucrase activity, occurred before the onset of diarrhea or opportunistic enteric infections. These findings indicate that macrophages and T cells in the intestinal tract are early targets of SIV infection and may play a critical role in the development of SIV-associated intestinal dysfunction.
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PMID:Primary acute simian immunodeficiency virus infection of intestinal lymphoid tissue is associated with gastrointestinal dysfunction. 816 4

Currently, there are no truly effective therapies for the treatment of chemotherapy-induced intestinal mucositis, a debilitating side effect with a pathophysiology common to many chemotherapy regimens. We tested the efficacy of a growth factor extract derived from cheese whey against experimental intestinal mucositis in rats. Rats were subcutaneously injected with the chemotherapeutic drug methotrexate on d 1, 2 and 3 to induce severe damage in the small bowel and bacterial translocation across the gut. Whey extract (15 to 514 mg/d) was given orally for 5-12 d, starting on d 1. Controls were fed an isonitrogenous diet. Histological indices of villus and crypt integrity were utilized to assess potential efficacy of the extract. Administration of the whey extract for 5 d increased the villus surface length indices in the jejunum and ileum by 52% and 56%, respectively (P< 0.001) compared with controls not receiving the whey extract. The crypt area index was 64% greater (P < 0.001) in the jejunum, but not significantly greater in the duodenum or ileum compared with controls not receiving whey extract. Similarly, sucrase activity was significantly higher in the ileum (P < 0.001) but not significantly elevated in the jejunum, whereas bacterial translocation (incidence and number of colonies) was significantly reduced compared with controls not receiving whey extract. We conclude that oral whey growth factor extract reduces methotrexate-induced damage in the small bowel, which suggests clinical applications for the treatment of intestinal mucositis.
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PMID:Milk growth factors enriched from cheese whey ameliorate intestinal damage by methotrexate when administered orally to rats. 885 13

Glucocorticoids are associated with reduced weight gain when used to improve pulmonary function in premature infants. However, tissue maturation is stimulated during normal development by an increase in serum glucocorticoids. We evaluated the effects of glucocorticoid treatment on tissue weight gain and the activity of specific enzymes in the suckling rat, with the hypothesis that these processes are independently regulated. Before the ontogenic surge in corticosterone, 6-d-old rat pups were implanted with a pellet to release corticosterone continuously at 0 (placebo), 48, 120, 240, or 360 micro g/d. We killed the pups at 7, 9, or 12 d of age and measured tissue weights and activities of sucrase and glutamine synthetase. Serum corticosterone concentrations were elevated with dose. Tissue weight gain was proportional to ln(e) serum corticosterone at all ages. In contrast, enzyme indices of tissue maturation did not respond to corticosterone until d9. Also, intestinal tissue was more sensitive than muscle to the effects of corticosterone on weight but less sensitive to its effects on maturation. We conclude that the immediate response, in terms of weight versus the delayed response of the enzymes and their reciprocal sensitivity in muscle and gut, indicates that these processes are independently regulated.
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PMID:Corticosterone has independent effects on tissue maturation and growth in the suckling rat. 892 57

Insulinlike growth factor-I (IGF-I) has been found in the milk of various species. To investigate if milk-borne IGF-I has any effect on postnatal gut development in neonatal animals, newborn rat pups were given orally 1 microg recombinant human IGF-I daily for 3 days. For comparison, a separate group of newborn pups was given 150 microg hydrocortisone, the hormone known to stimulate intestinal maturation in neonatal rats. Oral IGF-I treatment had no significant effect on the animal body weight nor on the weight of the stomach, small and large intestines, and pancreas. Oral administration of hydrocortisone significantly reduced body weight gain, but it had no apparent effect on internal organ weights. Both IGF-I and hydrocortisone treatments, however, significantly increased lactase, maltase and sucrase activities and hydrocortisone significantly increased aminopeptidase activity at the proximal small intestine when compared with the control. The finding supports the hypothesis that milk-borne IGF-I may play a role in regulating postnatal gut development in the suckling young.
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PMID:Oral insulinlike growth factor-I stimulates intestinal enzyme maturation in newborn rats. 920 Jun 69

In this study we investigated whether brain-gut peptides are implicated in the activation of the hypophysial-adrenal axis (HAA) in suckling rats treated orally with spermine. The first group of rats received i.p. injections of bombesin, vasoactive intestinal polypeptide (VIP), somatostatin or neurotensin, starting on day 11 of life, and killed on day 14. The small intestine was removed and analysed for its content of proteins, DNA, polyamines and for its specific activity (SA) of disaccharidases. The second group of rats received one of the hormones cited above and was killed 45 min after the treatment for determination of corticosterone plasma concentration. Rats of the third group were adrenalectomised then treated with bombesin as the first group. The fourth group of rats was orally treated with spermine and sacrificed 2, 3, 4, 6 and 8 h thereafter for analysis of plasma and intestinal concentrations of bombesin. The i.p. injection of bombesin increased the sucrase and maltase SA in the whole small intestine, while it decreased the lactase SA in the distal part. Intestinal weight and length, contents of DNA, protein, spermidine and spermine, and corticosterone plasma levels were enhanced by bombesin treatment. Somatostatin, neurotensin and VIP were ineffective on all the parameters studied. Adrenalectomy, in bombesin-treated rats, decreased the sucrase and maltase SA in the whole intestine, and decreased the lactase SA in the proximal intestine. It has no effect on intestinal weight and length, and protein content. Oral administration of spermine had no effect on plasma concentration of bombesin, whereas it decreased the content of this peptide in the whole small intestine. It is possible that bombesin may control intestinal development in suckling rats and be a link between the ingestion of spermine and the liberation of corticosterone by the adrenal glands.
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PMID:Involvement of bombesin in spermine-induced corticosterone secretion and intestinal maturation in suckling rats. 920 97


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