Regulation of Fe absorption by cultured intestinal epithelia (Caco-2) cell monolayers with varied Fe status

1996 ◽  
Vol 271 (3) ◽  
pp. G443-G447 ◽  
Author(s):  
V. Tapia ◽  
M. Arredondo ◽  
M. T. Nunez
Keyword(s):  
Intracellular Concentration ◽  
Apical Surface ◽  
Cell Monolayers ◽  
Intestinal Epithelia ◽  
Second Stage ◽  
Ferritin Synthesis ◽  
Fe Content ◽  
Fe Uptake ◽  
Fe Homeostasis

Body Fe homeostasis is maintained through the regulation of Fe absorption by the intestinal epithelia. Working under the hypothesis that the intracellular concentration of Fe is instrumental in the control of its transepithelial flux, we investigated in vitro which steps in Fe absorption are regulated by cellular Fe content. For that study, Caco-2 cells containing different concentrations of intracellular 55Fe were grown in porous filters, and the apical-to-cell-to- basolateral flux of 59Fe was then determined. We found that 1) at low (up to 0.1 mM) intracellular Fe content the apical-to-basal Fe transport was primarily regulated by a decrease in apical Fe uptake (first stage of regulation), 2) at higher levels of intracellular Fe (0.1-1 mM) the transepithelial Fe flux was regulated by intracellular factors that sequester most of the Fe taken up at the apical surface (second stage of regulation), and 3) a fraction of the apical-to-basolateral Fe flux was not regulated by the intracellular concentration of Fe. Ferritin synthesis preceded the onset of the second stage of regulation, suggesting a causal relationship between intracellular Fe levels, ferritin levels, and regulation of Fe absorption.

scholarly journals New Zealand green-lipped mussels (Perna canaliculus) enhance non-haem iron absorptionin vitro

2012 ◽  
Vol 108 (6) ◽  
pp. 949-952 ◽  
Author(s):  
Robin J. C. Stewart ◽  
Jane Coad ◽  
Gordon W. Reynolds ◽  
Kevin C. Pedley
Keyword(s):  
Ascorbic Acid ◽  
Positive Control ◽  
Negative Control ◽  
Nutritional Composition ◽  
Egg Albumin ◽  
Cell Monolayers ◽  
Perna Canaliculus ◽  
Fe Uptake ◽  
Haem Iron

Fe bioavailability can be manipulated by the nutritional composition of a meal. Ascorbic acid and unidentified components of meat, fish and poultry, but particularly beef, all appear to enhance the absorption of non-haem Fe. The aim of the present study is to identify whether extracts of green-lipped mussels (GLM;Perna canaliculus) enhance non-haem Fe absorption in Caco-2 cells and to compare the effect with that of beef. Raw GLM and raw beef homogenates were digestedin vitrowith pepsin at pH 2, and pancreatin and bile salts at pH 7. Tracer55Fe was used to measure cellular Fe uptake. Ascorbic acid was used as a positive control and egg albumin, exposed to the samein vitrodigestion process, was used as a negative control. Caco-2 cell monolayers were incubated with treatments for 60 min. All values were standardised per μg of GLM, egg albumin, beef or ascorbic acid. The results showed that ascorbic acid enhanced non-haem Fe absorption to the highest degree. Beef and GLM digestates both significantly enhanced Fe absorption compared with egg albumin. In conclusion, GLM digestate significantly enhances non-haem Fe uptake in Caco-2 cells with a similar magnitude to that of beef.

Chitosans for enhanced delivery of therapeutic peptides across intestinal epithelia: in vitro evaluation in Caco-2 cell monolayers

1997 ◽  
Vol 159 (2) ◽  
pp. 243-253 ◽  
Author(s):  
A.F Kotzé ◽  
B.J de Leeuw ◽  
H.L Lueßen ◽  
A.G de Boer ◽  
J.C Verhoef ◽  
...  
Keyword(s):  
In Vitro Evaluation ◽  
Cell Monolayers ◽  
Intestinal Epithelia ◽  
Therapeutic Peptides

Ultrastructural autoradiography of L6 skeletal-muscle cells exposed to a tritiated macrolide antibiotic (LY237216) in vitro

1992 ◽  
Vol 50 (1) ◽  
pp. 612-613
Author(s):  
S.L. White ◽  
C.B. Jensen ◽  
D.D. Giera ◽  
D.A. Laska ◽  
M.N. Novilla ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Quantitative Analysis ◽  
Macrolide Antibiotic ◽  
Circle Method ◽  
Apical Surface ◽  
Polycarbonate Membrane ◽  
L6 Cells ◽  
Low Viscosity ◽  
Erythromycin A

In vitro exposure to LY237216 (9-Deoxo-11-deoxy-9,11-{imino[2-(2-methoxyethoxy)ethylidene]-oxy}-(9S)-erythromycin), a macrolide antibiotic, was found to induce cytoplasmic vacuolation in L6 skeletal muscle myoblast cultures (White, S.L., unpubl). The present study was done to determine, by autoradiographic quantitative analysis, the subcellular distribution of 3H-LY237216 in L6 cells.L6 cells (ATCC, CRL 1458) were cultured to confluency on polycarbonate membrane filters (Millipore Corp., Bedford, MA) in M-199 medium (GIBCO® Labs) with 10% fetal bovine serum. The cells were exposed from the apical surface for 1-hour to unlabelled-compound (0 μCi/ml) or 50 (μCi/ml of 3H-LY237216 at a compound concentration of 0.25 mg/ml. Following a rapid rinse in compound-free growth medium, the cells were slam-frozen against a liquid nitrogen cooled, polished copper block in a CF-100 cryofixation unit (LifeCell Corp., The Woodlands, TX). Specimens were dried in the MDD-C Molecular Distillation Drier (LifeCell Corp.), vapor osmicated and embedded in Spurrs low viscosity resin. Ultrathin sections collected on formvar coated stainless steel grids were counter-stained, then individually mounted on corks. A monolayer of Ilford L4 nuclear emulsion (Polysciences, Inc., Warrington, PA) was placed on the sections, utilizing a modified “loop method”. The emulsions were exposed for 7-weeks in a light-tight box at 4°C. Autoradiographs were developed in Microdol-X developer and examined on a Philips EM410LS transmission electron microscope. Quantitative analysis of compound localization employed the point and circle approach of Williams; incorporating the probability circle method of Salpeter and McHenry.

Perturbation of Platelet Adhesion to Endothelial Cells by Plasminogen Activation In Vitro

1997 ◽  
Vol 78 (02) ◽  
pp. 934-938 ◽  
Author(s):  
Hsiun-ing Chen ◽  
Yueh-I Wu ◽  
Yu-Lun Hsieh ◽  
Guey-Yueh Shi ◽  
Meei-Jyh Jiang ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Endothelial Cells ◽  
Platelet Adhesion ◽  
Treatment Time ◽  
Shape Change ◽  
Umbilical Vein ◽  
Tissue Type ◽  
Apical Surface ◽  
Plasminogen Activation

SummaryTo investigate whether the endothelium-platelet interactions may be altered by plasminogen activation, cultured human umbilical vein endothelial cells (ECs) were treated with tissue-type plasminogen activator (t-PA) in the presence of plasminogen, and platelet adhesion to ECs was subsequently measured by using a tapered flow chamber. Our results demonstrated that platelets adhered more readily to t-PA treated EC monolayer than to the control monolayer at all shear stress levels tested. This phenomenon was treatment time-dependent and dose-dependent, and it could be blocked by adding plasmin inhibitors, such as e-amino caproic acid and aprotinin. Adherent platelets on t-PA treated EC monolayer underwent more severe shape change than those on the control monolayer. While the extracellular matrix directly treated with t-PA attracted less platelets than the control matrix did, platelet adhesion to the matrix that was produced by t-PA-treated ECs was unaltered. These data suggest that t-PA treatment on ECs compromised antiplatelet-adhesion capability on their apical surface without altering the reactivity of their extracellular matrix towards platelets.

In vitro maturation of canine oocytes co-cultured with bovine and canine granulosa cell monolayers

2012 ◽  
Vol 77 (2) ◽  
pp. 347-355 ◽  
Author(s):  
Mohammed Ali Abdel-Ghani ◽  
Takashi Shimizu ◽  
Tomoyoshi Asano ◽  
Hiroshi Suzuki
Keyword(s):  
Granulosa Cell ◽  
In Vitro Maturation ◽  
Cell Monolayers

scholarly journals Investigation of Wall Shear Stress in Cardiovascular Research and in Clinical Practice—From Bench to Bedside

2021 ◽  
Vol 22 (11) ◽  
pp. 5635
Author(s):  
Katharina Urschel ◽  
Miyuki Tauchi ◽  
Stephan Achenbach ◽  
Barbara Dietel
Keyword(s):  
Endothelial Cells ◽  
Shear Stress ◽  
Wall Shear Stress ◽  
Cell Function ◽  
Computational Techniques ◽  
Apical Surface ◽  
Cardiovascular Research ◽  
Endothelial Cell Function ◽  
Wall Shear

In the 1900s, researchers established animal models experimentally to induce atherosclerosis by feeding them with a cholesterol-rich diet. It is now accepted that high circulating cholesterol is one of the main causes of atherosclerosis; however, plaque localization cannot be explained solely by hyperlipidemia. A tremendous amount of studies has demonstrated that hemodynamic forces modify endothelial athero-susceptibility phenotypes. Endothelial cells possess mechanosensors on the apical surface to detect a blood stream-induced force on the vessel wall, known as “wall shear stress (WSS)”, and induce cellular and molecular responses. Investigations to elucidate the mechanisms of this process are on-going: on the one hand, hemodynamics in complex vessel systems have been described in detail, owing to the recent progress in imaging and computational techniques. On the other hand, investigations using unique in vitro chamber systems with various flow applications have enhanced the understanding of WSS-induced changes in endothelial cell function and the involvement of the glycocalyx, the apical surface layer of endothelial cells, in this process. In the clinical setting, attempts have been made to measure WSS and/or glycocalyx degradation non-invasively, for the purpose of their diagnostic utilization. An increasing body of evidence shows that WSS, as well as serum glycocalyx components, can serve as a predicting factor for atherosclerosis development and, most importantly, for the rupture of plaques in patients with high risk of coronary heart disease.

scholarly journals In-vitro study of Limosilactobacillus fermentum PCC adhesion to and integrity of the Caco-2 cell monolayers as affected by pectins

2021 ◽  
Vol 79 ◽  
pp. 104395
Author(s):  
Thanyaporn Srimahaeak ◽  
Fernanda Bianchi ◽  
Ondrej Chlumsky ◽  
Nadja Larsen ◽  
Lene Jespersen
Keyword(s):  
In Vitro Study ◽  
Vitro Study ◽  
Cell Monolayers

scholarly journals Pharmacological targeting of host chaperones protects from pertussis toxin in vitro and in vivo

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Katharina Ernst ◽  
Ann-Katrin Mittler ◽  
Veronika Winkelmann ◽  
Carolin Kling ◽  
Nina Eberhardt ◽  
...  
Keyword(s):  
Pertussis Toxin ◽  
Airway Epithelium ◽  
Whooping Cough ◽  
Apical Surface ◽  
Basal Cells ◽  
Pharmacological Chaperone ◽  
Infant Mouse ◽  
Novel Therapeutic Strategies

AbstractWhooping cough is caused by Bordetella pertussis that releases pertussis toxin (PT) which comprises enzyme A-subunit PTS1 and binding/transport B-subunit. After receptor-mediated endocytosis, PT reaches the endoplasmic reticulum from where unfolded PTS1 is transported to the cytosol. PTS1 ADP-ribosylates G-protein α-subunits resulting in increased cAMP signaling. Here, a role of target cell chaperones Hsp90, Hsp70, cyclophilins and FK506-binding proteins for cytosolic PTS1-uptake is demonstrated. PTS1 specifically and directly interacts with chaperones in vitro and in cells. Specific pharmacological chaperone inhibition protects CHO-K1, human primary airway basal cells and a fully differentiated airway epithelium from PT-intoxication by reducing intracellular PTS1-amounts without affecting cell binding or enzyme activity. PT is internalized by human airway epithelium secretory but not ciliated cells and leads to increase of apical surface liquid. Cyclophilin-inhibitors reduced leukocytosis in infant mouse model of pertussis, indicating their promising potential for developing novel therapeutic strategies against whooping cough.

scholarly journals Seed treatment for management of Meloidogyne javanica in soybean

2017 ◽  
Vol 38 (5) ◽  
pp. 2995 ◽  
Author(s):  
Adriely Alves de Almeida ◽  
Vinicius Hicaro Frederico Abe ◽  
Ricardo Marcelo Gonçalves ◽  
Maria Isabel Balbi-Peña ◽  
Débora Cristina Santiago
Keyword(s):  
Seed Treatment ◽  
Meloidogyne Javanica ◽  
Vitro Assay ◽  
Juvenile Mortality ◽  
Second Stage ◽  
Final Population ◽  
Randomized Design ◽  
Completely Randomized Design ◽  
Soybean Plants

The objective of this study was to evaluate the efficacy of the active ingredient abamectin, either in isolation or in combination with fungicides and insecticides formulated for the industrial seed treatment, on the population of Meloidogyne javanica, tested under greenhouse and in vitro conditions. In both tests, the combination of the following treatments was assessed: abamectin; thiamethoxam; fludioxonil + metalaxyl-M + thiabendazole. Water was used as control for the in vitro assay, whereas under greenhouse conditions, controls were inoculated and not inoculated with M. javanica. The tests were conducted in a completely randomized design with six (in vitro) and ten (greenhouse) replicates. For in vitro studies the effect on hatching, motility, and mortality of juveniles of M. javanica was evaluated. Under greenhouse conditions, the soybean ‘BRS 133’ seeds were treated, and at 15, 30, and 60 days after inoculation (DAI) with M. javanica, plant measurements were recorded. The penetration of second stage juveniles (J2) was also evaluated at 15 DAI. At 30 DAI, galls, egg masses, nematodes/g of root, and final population were evaluated. At 60 DAI, the final population of nematodes in the roots was quantified. The treatments containing abamectin were the most effective in diminishing the hatching of juveniles. All treatments had an effect on nematode motility when compared to the control, and in the treatment containing only abamectin, total juvenile mortality was observed. In greenhouse conditions, at 15 DAI, the treated soybean plants had the highest root mass and shoot length, differing statistically from the inoculated control. All treatments reduced the number of nematodes per gram of root, differing from the control. At 30 DAI, treatment efficiency was observed in reducing the final population of M. javanica, particularly the treatments using abamectin, and abamectin + thiamethoxam + fludioxonil + metalaxyl-M + thiabendazole. However, at 60 DAI, the effect of the treatments on the population of M. javanica did not persist.

scholarly journals Bacillus cereus Induces Permeability of an In Vitro Blood-Retina Barrier

2008 ◽  
Vol 76 (4) ◽  
pp. 1358-1367 ◽  
Author(s):  
A. L. Moyer ◽  
R. T. Ramadan ◽  
J. Thurman ◽  
A. Burroughs ◽  
M. C. Callegan
Keyword(s):  
Quorum Sensing ◽  
Bacillus Cereus ◽  
Barrier Function ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Toxin Production ◽  
Global Regulator ◽  
Barrier Permeability ◽  
Cell Monolayers

ABSTRACT Most Bacillus cereus toxin production is controlled by the quorum-sensing-dependent, pleiotropic global regulator plcR, which contributes to the organism's virulence in the eye. The purpose of this study was to analyze the effects of B. cereus infection and plcR-regulated toxins on the barrier function of retinal pigment epithelium (RPE) cells, the primary cells of the blood-retina barrier. Human ARPE-19 cells were apically inoculated with wild-type or quorum-sensing-deficient B. cereus, and cytotoxicity was analyzed. plcR-regulated toxins were not required for B. cereus-induced RPE cytotoxicity, but these toxins did increase the rate of cell death, primarily by necrosis. B. cereus infection of polarized RPE cell monolayers resulted in increased barrier permeability, independent of plcR-regulated toxins. Loss of both occludin and ZO-1 expression occurred by 8 h postinfection, but alterations in tight junctions appeared to precede cytotoxicity. Of the several proinflammatory cytokines analyzed, only interleukin-6 was produced in response to B. cereus infection. These results demonstrate the deleterious effects of B. cereus infection on RPE barrier function and suggest that plcR-regulated toxins may not contribute significantly to RPE barrier permeability during infection.

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