The object of this study was to investigate the effect of probiotic Escherichia coli strain Nissle 1917 (EcN) (i) EcN lipopolysaccharide (EcN LPS) and (ii) bacteria-free supernatant of EcN suspension (EcN supernatant) on in vitro transepithelial transport of mesalazine (5-aminosalicylic acid, 5-ASA), the most commonly prescribed anti-inflammatory drug in inflammatory bowel disease (IBD). Effect of co-administered EcN LPS (100 µg/ml) or EcN supernatant (50 µg/ml) on the 5-ASA transport (300 µmol/l) was studied using the Caco-2 monolayer (a human colon carcinoma cell line) as a model of human intestinal absorption. Permeability characteristics for absorptive and secretory transport of parent drug and its intracellularly-formed metabolite were determined. The quantification of 5-ASA and its main metabolite N-acetyl-5-amino-salicylic acid (N-Ac-5-ASA) was performed by high performance liquid chromatography. Obtained results suggest that neither EcN LPS nor EcN supernatant had effect on the total 5-ASA transport (secretory flux greater than absorptive flux) and on the transport of intracellularly formed N-Ac-5-ASA (preferentially transported in the secretory direction). The percent cumulative transport of the total 5-ASA alone or in combination with EcN LPS or EcN supernatant did not exceed 1%.
- MeSH
- antiflogistika nesteroidní metabolismus MeSH
- biologický transport účinky léků MeSH
- Caco-2 buňky MeSH
- epitelové buňky cytologie účinky léků metabolismus MeSH
- Escherichia coli chemie MeSH
- intracelulární prostor účinky léků metabolismus MeSH
- kultivační média speciální chemie MeSH
- lidé MeSH
- lipopolysacharidy farmakologie MeSH
- mesalamin metabolismus MeSH
- permeabilita účinky léků MeSH
- probiotika chemie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
OBJECTIVES: Different probiotic strains used in clinical trials have shown prophylactic properties in different inflammatory diseases of the gastrointestinal tract. This study was aimed to investigate the influence of Escherichia coli strain Nissle 1917 (EcN) components on the integrity of the Caco-2 cell monolayer (human adenocarcinoma cell line). METHODS: The effect of supernatant of EcN suspension and lipopolysaccharide (LPS) isolated from EcN (in concentrations from 0.001 to 1 000 µg/ml) on paracellular transport of 14C-mannitol marker through epithelial cell monolayer was estimated. RESULTS: Both LPS and EcN supernatant exerted almost the same effect; whereas no effect was shown using high concentrations (100 and 1 000 µg/ml), low concentrations (0.001, 0.1 and 1 µg/ml) significantly decreased permeability of 14C-mannitol. Concentration (0.001 µg/ml) decreased 14C-mannitol permeability approximately about 20% (LPS) and 30% (EcN supernatant). To elucidate the observed changes in monolayer permeability ("tighter monolayer") induced by concentrations of LPS or supernatant, media able to open epithelial intercellular junctions were used. The effects of Ca2+-free transport medium and of medium containing 5, 10, 20, 50, and 100% of Ca2+ on the 14C-mannitol transport in the presence of the lowest (0.001 µg/ml) and high (100 µg/ml) concentrations of LPS were studied. Using Ca2+-free medium both concentrations of LPS significantly decreased apparent permeability coefficient (Papp) of 14C-mannitol indicating that changes of 14C-mannitol permeability are independent of dimensions of paracellular spaces. CONCLUSION: The decrease of 14C-mannitol permeability caused by EcN LPS indicates the ability of components of probiotic EcN strain to restore disrupted epithelial barrier.
- MeSH
- adenokarcinom metabolismus patologie MeSH
- Caco-2 buňky MeSH
- Escherichia coli MeSH
- lidé MeSH
- lipopolysacharidy farmakologie MeSH
- mannitol metabolismus MeSH
- nádory tračníku metabolismus patologie MeSH
- permeabilita buněčné membrány účinky léků MeSH
- probiotika farmakologie MeSH
- radioizotopy uhlíku MeSH
- viabilita buněk účinky léků MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
This study aimed i) to characterize the transepithelial transport of the mucolytic agent ambroxol hydrochloride across the intestinal barrier, ii) to classify the ambroxol according to Biopharmaceutics Classification System (BCS) and iii) to predict ambroxol absorption in humans. Transport of ambroxol (100, 300 and 1000 micromol/l) was studied in a human colon carcinoma cell line Caco-2 in apical to basolateral and basolateral to apical direction, under iso-pH 7.4 and pH-gradient (6 vs. 7.4) conditions. The relative contribution of the paracellular route was estimated using Ca2+-free transport medium. Ambroxol samples from receiver compartments were analysed by HPLC with UV detection (242 nm). Results showed that ambroxol transport is linear with time, pH-dependent and direction-independent, displays non-saturable (first-order) kinetics. Thus, the transport seems to be transcellular mediated by passive diffusion. Estimated high solubility and high permeability (P(app) = 45 x 10(-6) cm/s) of ambroxol rank it among well absorbed compounds and class I of BCS. It can be expected that the oral dose fraction of ambroxol absorbed in human intestine is high.
- MeSH
- absorpce MeSH
- ambroxol aplikace a dávkování farmakokinetika klasifikace MeSH
- biologické modely MeSH
- epitel metabolismus MeSH
- expektorancia aplikace a dávkování farmakokinetika klasifikace MeSH
- karcinom metabolismus MeSH
- kinetika MeSH
- koncentrace vodíkových iontů MeSH
- lidé MeSH
- lineární modely MeSH
- nádorové buněčné linie MeSH
- nádory tračníku metabolismus MeSH
- permeabilita MeSH
- rozpustnost MeSH
- ultrafialové záření MeSH
- vápník nedostatek MeSH
- vysokoúčinná kapalinová chromatografie metody MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
The relationship between the pharmacokinetics of gliclazide and its antidiabetic efficacy were evaluated on the basis of experimental determination of changes with time in the plasma levels of this antidiabetic agent and those of glucose. The experiment included rats with both initial normal glycaemia and alloxan-induced hyperglycaemia (glycaemia increased by a minimum of 30%). Pharmacokinetic and pharmacodynamic parameters were examined in the interval of 30 to 180 min after p.o. administration of a single dose of 25 mg/kg of gliclazide. The drug was administered on day 4, following a single i.v. dose of either 50 mg/kg of alloxan (hyperglycaemic group) or the injection vehicle (control group). Even though the biological availability of gliclazide was similar in both normoglycaemic and hyperglycaemic animals, the gliclazide-induced hypoglycaemizing response was not uniform: until 60 min, the decrease of glycaemia was smaller in animals with alloxan hyperglycaemia (23% decrease at 60 min) in contrast to the normoglycaemic animals (36% decrease at 60 min), at later times, the intensity of this hypoglycaemizing effect of gliclazide persisted in the hyperglycaemic animals, while in the normoglycaemic ones, a reversal of the hypoglycaemizing effect occurred. Copyright (c) 2007 John Wiley & Sons, Ltd.
- MeSH
- alloxan aplikace a dávkování toxicita MeSH
- aplikace orální MeSH
- časové faktory MeSH
- financování organizované MeSH
- gliklazid farmakokinetika krev terapeutické užití MeSH
- hyperglykemie farmakoterapie chemicky indukované krev MeSH
- hypoglykemika aplikace a dávkování farmakokinetika terapeutické užití MeSH
- injekce intravenózní MeSH
- inzulin krev MeSH
- krevní glukóza metabolismus MeSH
- krysa rodu rattus MeSH
- plocha pod křivkou MeSH
- potkani Wistar MeSH
- vysokoúčinná kapalinová chromatografie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- abstrakt z konference MeSH
