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 role of extracellular matrix as a determinant of intestinal cell maturation was explored by growing a normal, but immature, rat small intestinal cell line (IEC-6) on basement membrane extract from Engelbreth-Holm-Swarm (EHS) sarcoma cells (ECM). Grown on plastic or glass, these cells are relatively immature and proliferate rapidly. In contrast, cells on ECM attached more rapidly, stopped proliferating, and rapidly organized into multicellular complex structures. Ultrastructurally, cells grown on ECM displayed significantly more mitochondria, rough endoplasmic reticulum, apical microvilli, and complex golgi apparatus, consistent with greater maturity and synthetic activity. By indirect immunofluorescence, sucrase, alkaline phosphatase, and cellular apolipoprotein B were present in cells grown on ECM only. In contrast to cells grown on glass, these cells also demonstrated Na-dependent glucose absorption, a function unique to mature villus cells (7). We conclude that the basement membrane may be a key determinant of intestinal epithelial cell maturation. The development of a mature villuslike intestinal cell in vitro may have wide application for future studies of induction and regulation of intestinal maturation and function.
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PMID:Differentiation of rat small intestinal epithelial cells by extracellular matrix. 334 2

Several lines of evidence suggest that long-term treatment with non-steroidal anti-inflammatory drugs may reduce the risk of colon cancer and the size and number of colonic polyps in patients with familial adenomatous polyposis. Aspirin has also been shown to inhibit cell proliferation in human tumor cell lines and to induce apoptosis in colonic mucosa of familial polyposis patients. To elucidate the molecular mechanisms of the antiproliferative action of aspirin, we studied the effects of aspirin on cell growth and differentiation of the human colon carcinoma Caco-2 cell line. These cells represent a useful tool for studying the mechanisms involved in the regulation of cell growth and differentiation of intestinal epithelial cells since they spontaneously differentiate into polarized cells, expressing brush border enzymes. We show in this study that aspirin (0.1-10 mM) induces a profound inhibition of cell replication as assessed either by cell counts or thymidine incorporation. Moreover, aspirin concentrations of 5 and 10 mM induce apoptosis, whereas concentrations of 1 and 2 mM do not. The inhibition of growth is associated with a dose-dependent reduction in insulin-like growth factor II mRNA expression and with an increase in sucrase activity (a brush border enzyme) and apolipoprotein A-I mRNA expression, 2 specific markers of the differentiative status of this cell line. Our data thus show that aspirin-dependent inhibition of cell growth is associated with the enterocyte-like differentiation of Caco-2 cells.
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PMID:Effect of aspirin on cell proliferation and differentiation of colon adenocarcinoma Caco-2 cells. 939 70

In the present study the effects of two cycloxygenase-2 (COX-2) selective inhibitors, celecoxib and nimesulide as compared to a non-selective COX inhibitor, aspirin was studied in the rat intestine. Female Wistar rats weighing between 150-175 g were divided into four groups having 8 animals each as follows: Group 1(Control), Group 2- Aspirin (40 mg/kg), Group 3- Nimesulide (10 mg/kg) and Group 4- Celecoxib (10 mg/kg). After 35 days of treatment the animals were sacrificed, intestine removed and the effects on the antioxidant defense system, membrane composition and functions along with the membrane specific enzymes were studied in different regions of the intestine. The study showed a significant increase in the lipid peroxide levels as TBA-reactive substance as well as the conjugated dienes, except for celecoxib treated group which showed a decrease. Significant decrease was also observed in the level of reduced glutathione (GSH), superoxide dismutase (SOD), glutathione-s-transferase and catalase activities for aspirin and nimesulide group while Celecoxib caused an increase in glutathione reductase (GR). Aspirin and nimesulide exhibited an increase in the brush border membrane (BBM) bound enzyme activities like sucrase, lactase, maltase and alkaline phosphatase in the small intestine while celecoxib showed decrease in lactase, maltase and alkaline phosphatase. The phospholipid content increased only for aspirin treated group while cholesterol decreased in all the treatment groups. Also celecoxib treatment brought about an increase in glycolipid content. The membrane fluidity was studied by the rotational diffusion of 1, 6, diphenyl, 1, 3, 5 hexatriene (DPH) incorporated in the membrane and the fluorescence polarization (p), fluorescence anisotropy(r), anisotropy parameter [r0/r-1](-1) and order parameter [S2 = (4/3r - 0.1)/r0] were recorded. No significant change in the fluorescence parameters were observed in the BBM and the liposomes made from the BBM lipids for the treatment groups. These results indicate that celecoxib may be accepted as a safer drug in terms of overall gastro-intestinal toxicity as compared to the aspirin and nimesulide.
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PMID:Effects of non steroidal anti-inflammatory drugs on the antioxidant defense system and the membrane functions in the rat intestine. 1714 60

Aspirin at a dose of 50 mg/kg body weight was found to decrease the activity of the rat intestinal brush border membrane (BBM) - associated enzymes such as the sucrase, lactase, maltase and alkaline phosphatase. Aspirin treatment also led to a decrease in the microviscosity in the native as well as the benzyl alcohol treated membrane which might be due to the lipid peroxidative damage in the membrane. Physical correlation of the membrane oxidative damage was evident as the Fourier Transformation Infra Red (FTIR) study of the Aspirin treated membrane, which include an increased proportion of gauche to trans conformer, shift in the methylene C-H asymmetric and symmetric stretching frequencies, C = O double bond stretching, NH bending, antisymmetric (N)-CH3 bending, C-N stretching and antisymmetric CNC stretching while there was no change in the CH2 wagging and twisting as well as in NH-bending amide bond I and II. Aspirin treatment also caused an alteration in the glucose and histidine transport, as evident by a decreased Vmax value while the apparent Km remaining unchanged in the control and Aspirin-treated animals confirming that there was no change in the substrate affinity constant of the membrane transport proteins for the glucose and the basic amino acid, although the rate of transport decreased considerably. There was a decrease noted in the energy of activation of glucose and histidine transport when studied at different temperature but no change in the temperature of phase transition in the BBM with Aspirin treatment, thus implying that perhaps the thermotropic phase transition in the membrane may have relatively little effect on the transport processes. The result suggests an underlying molecular mechanism indicating the implied membrane damage by Aspirin, an important member of the non-steroidal antiinflammatory drug (NSAID) family which could possibly through an oxidative damage may lead to an altered molecular structure, physical state and biological functions of the intestinal membrane.
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PMID:The effect of prostaglandin synthase inhibitor, aspirin on the rat intestinal membrane structure and function. 2044 40