Ex vivo and in vitro poultry intestinal models to evaluate antimycotoxins additives

ABSTRACT: In vitro tests are performed to evaluate the efficacy of antimycotoxins additives (AMAs); nevertheless, such assays show a low correlation with in vivo trials, which are also required to determine AMAs’ efficacy. In search of an alternative method, the current study investigated the use of an ex vivo technique. Six AMAs (AMA1 to AMA6) had their ability to reduce intestinal absorption of aflatoxin B1 (AFB1) evaluated. Jejunal explants were obtained from broilers and subjected to two treatments per AMA in Ussing chambers: T1 (control) - 2.8 mg/L AFB1, and T2 - 2.8 mg/L AFB1 + 0.5% AMA. AMAs were also tested in vitro to assess adsorption of AFB1 in artificial intestinal fluid. In the ex vivo studies, AMA1 to AMA6 decreased intestinal absorption of AFB1 by 67.11%, 73.82%, 80.70%, 85.86%, 86.28% and 82.32%, respectively. As for the in vitro results, AMA1 to AMA6 presented an adsorption of 99.72%, 99.37%, 99.67%, 99.53%, 99.04% and 99.15%, respectively. The evaluated ex vivo model proved useful in the assessment of AMAs. No correlation was reported between ex vivo and in vitro findings. Further studies are needed to elucidate the correlation between ex vivo and in vivo results seeking to reduce animal testing.

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Considerations to Model Heart Disease in Women with Preeclampsia and Cardiovascular Disease

Cells ◽

10.3390/cells10040899 ◽

2021 ◽

Vol 10 (4) ◽

pp. 899

Author(s):

Clara Liu Chung Ming ◽

Kimberly Sesperez ◽

Eitan Ben-Sefer ◽

David Arpon ◽

Kristine McGrath ◽

...

Keyword(s):

Myocardial Infarction ◽

Cardiovascular Disease ◽

Ex Vivo ◽

Myocardial Damage ◽

Cardiovascular Disorder ◽

Model Systems ◽

Ex Vivo Model ◽

Disease Manifestation

Preeclampsia is a multifactorial cardiovascular disorder diagnosed after 20 weeks of gestation, and is the leading cause of death for both mothers and babies in pregnancy. The pathophysiology remains poorly understood due to the variability and unpredictability of disease manifestation when studied in animal models. After preeclampsia, both mothers and offspring have a higher risk of cardiovascular disease (CVD), including myocardial infarction or heart attack and heart failure (HF). Myocardial infarction is an acute myocardial damage that can be treated through reperfusion; however, this therapeutic approach leads to ischemic/reperfusion injury (IRI), often leading to HF. In this review, we compared the current in vivo, in vitro and ex vivo model systems used to study preeclampsia, IRI and HF. Future studies aiming at evaluating CVD in preeclampsia patients could benefit from novel models that better mimic the complex scenario described in this article.

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Considerations to Model Heart Disease in Women with Preeclampsia and Cardiovascular Disease

10.20944/preprints202104.0240.v1 ◽

2021 ◽

Author(s):

Clara Liu Chung Ming ◽

Kimberly Sesperez ◽

Eitan Ben-Sefer ◽

David Arpon ◽

Kristine McGrath ◽

...

Keyword(s):

Myocardial Infarction ◽

Cardiovascular Disease ◽

Ex Vivo ◽

Myocardial Damage ◽

Cardiovascular Disorder ◽

Model Systems ◽

Ex Vivo Model ◽

Disease Manifestation

Preeclampsia is a multifactorial cardiovascular disorder diagnosed after 20 weeks of gestation that is the leading cause of death for both mothers and babies in pregnancy. The pathophysiology remains poorly understood due to variability and unpredictability of disease manifestation when studied in animal models. After preeclampsia, both mothers and offspring have a higher risk of cardiovascular disease (CVD) including myocardial infarction or heart attack and heart failure (HF). Myocardial infarction is an acute myocardial damage that can be treated through reperfusion, however, that therapeutic approach leads to ischemic/reperfusion injury (IRI) often leading to HF. In this review, we compared the current in vivo, in vitro and ex vivo model systems used to study preeclampsia, IRI and HF. Future studies aiming at evaluating CVD in preeclampsia patients could benefit from novel models that better mimic the complex scenario described in this article.

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The MEMIC: An ex vivo system to model the complexity of the tumor microenvironment

Disease Models & Mechanisms ◽

10.1242/dmm.048942 ◽

2021 ◽

Author(s):

Libuše Janská ◽

Libi Anandi ◽

Nell C. Kirchberger ◽

Zoran S. Marinkovic ◽

Logan T. Schachtner ◽

...

Keyword(s):

Tumor Microenvironment ◽

Tumor Cells ◽

Ex Vivo ◽

Tumor Stroma ◽

Stem Cell Differentiation ◽

Blood Stream ◽

Direct Access ◽

Ex Vivo Model

There is an urgent need for accurate, scalable, and cost-efficient experimental systems to model the complexity of the tumor microenvironment. Here, we detail how to fabricate and use the Metabolic Microenvironment Chamber (MEMIC) – a 3D-printed ex vivo model of intratumoral heterogeneity. A major driver of the cellular and molecular diversity in tumors is the accessibility to the blood stream that provides key resources such as oxygen and nutrients. While some tumor cells have direct access to these resources, many others must survive under progressively more ischemic environments as they reside further from the vasculature. The MEMIC is designed to simulate the differential access to nutrients and allows co-culturing different cell types, such as tumor and immune cells. This system is optimized for live imaging and other microscopy-based approaches, and it is a powerful tool to study tumor features such as the effect of nutrient scarcity on tumor-stroma interactions. Due to its adaptable design and full experimental control, the MEMIC provide insights into the tumor microenvironment that would be difficult to obtain via other methods. As a proof of principle, we show that cells sense gradual changes in metabolite concentration resulting in multicellular spatial patterns of signal activation and cell proliferation. To illustrate the ease of studying cell-cell interactions in the MEMIC, we show that ischemic macrophages reduce epithelial features in neighboring tumor cells. We propose the MEMIC as a complement to standard in vitro and in vivo experiments, diversifying the tools available to accurately model, perturb, and monitor the tumor microenvironment, as well as to understand how extracellular metabolites affect other processes such as wound healing and stem cell differentiation.

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Detection of allergen-induced airway hyperresponsiveness in isolated mouse lungs

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00011.2005 ◽

2006 ◽

Vol 291 (3) ◽

pp. L466-L472 ◽

Cited By ~ 22

Author(s):

Martin Witzenrath ◽

Birgit Ahrens ◽

Stefanie M. Kube ◽

Armin Braun ◽

Heinz G. Hoymann ◽

...

Keyword(s):

Airway Hyperresponsiveness ◽

Ex Vivo ◽

Whole Body ◽

Strongly Correlated ◽

Ex Vivo Model ◽

Isolated Lungs ◽

Spontaneously Breathing

Airway hyperresponsiveness (AHR) is a hallmark of bronchial asthma. Important features of this exaggerated response to bronchoconstrictive stimuli have mostly been investigated in vivo in intact animals or in vitro in isolated tracheal or bronchial tissues. Both approaches have important advantages but also certain limitations. Therefore, the aim of our study was to develop an ex vivo model of isolated lungs from sensitized mice for the investigation of airway responsiveness (AR). BALB/c mice were sensitized by intraperitoneal ovalbumin (Ova) and subsequently challenged by Ova inhalation. In vivo AR was measured in unrestrained animals by whole body plethysmography after stimulation with aerosolized methacholine (MCh) with determination of enhanced pause ( Penh). Twenty-four hours after each Penh measurement, airway resistance was continuously registered in isolated, perfused, and ventilated lungs on stimulation with inhaled or intravascular MCh or nebulized Ova. In a subset of experiments, in vivo AR was additionally measured in orotracheally intubated, spontaneously breathing mice 24 h after Penh measurement, and lungs were isolated further 24 h later. Isolated lungs of allergen-sensitized and -challenged mice showed increased AR after MCh inhalation or infusion as well as after specific provocation with aerosolized allergen. AR was increased on days 2 and 5 after Ova challenge and had returned to baseline on day 9. AHR in isolated lungs after aerosolized or intravascular MCh strongly correlated with in vivo AR. Pretreatment of isolated lungs with the β2-agonist fenoterol diminished AR. In conclusion, this model provides new opportunities to investigate mechanisms of AHR as well as pharmacological interventions on an intact organ level.

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Ex Vivo Enteroids Recapitulate In Vivo Citrulline Production in Mice

Journal of Nutrition ◽

10.1093/jn/nxy126 ◽

2018 ◽

Vol 148 (9) ◽

pp. 1415-1420 ◽

Cited By ~ 1

Author(s):

Xiaoying Wang ◽

Yang Yuan ◽

Inka C Didelija ◽

Mahmoud A Mohammad ◽

Juan C Marini

Keyword(s):

Ex Vivo ◽

Transcript Abundance ◽

Mutant Mice ◽

Ex Vivo Model ◽

Endogenous Production ◽

Gene Coding ◽

Cycle Disorders ◽

Deficient Mice

Abstract Background The endogenous production of arginine relies on the synthesis of citrulline by enteral ornithine transcarbamylase (OTC). Mutations in the gene coding for this enzyme are the most frequent cause of urea cycle disorders. There is a lack of correlation between in vivo metabolic function and DNA sequence, transcript abundance, or in vitro enzyme activity. Objective The goal of the present work was to test the hypothesis that enteroids, a novel ex vivo model, are able to recapitulate the in vivo citrulline production of wild-type (WT) and mutant mice. Methods Six-week-old male WT and OTC-deficient mice [sparse fur and abnormal skin (spf-ash) mutation] were studied. Urea and citrulline fluxes were determined in vivo, and OTC abundance was measured in liver and gut tissue. Intestinal crypts were isolated and cultured to develop enteroids. Ex vivo citrulline production and OTC abundance were determined in these enteroids. Results Liver OTC abundance was lower (mean ± SE: 0.16 ± 0.01 compared with 1.85 ± 0.18 arbitrary units; P < 0.001) in spf-ash mice than in WT mice, but there was no difference in urea production. In gut tissue, OTC was barely detectable in mutant mice; despite this, a lower but substantial citrulline production (67 ± 3 compared with 167 ± 8 µmol · kg−1 · h−1; P < 0.001) was shown in the mutant mice. Enteroids recapitulated the in vivo findings of a very low OTC content accompanied by a reduced citrulline production (1.07 ± 0.20 compared with 4.64 ± 0.44 nmol · µg DNA−1 · d−1; P < 0.001). Conclusions Enteroids recapitulate in vivo citrulline production and offer the opportunity to study the regulation of citrulline production in a highly manipulable system.

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Hypotensive effects of the triterpene oleanolic acid for cardiovascular prevention

Current Molecular Pharmacology ◽

10.2174/1874467213999201230211544 ◽

2020 ◽

Vol 13 ◽

Author(s):

A. Sureda ◽

M. Monserrat-Mesquida ◽

S. Pinya ◽

P. Ferriol ◽

S. Tejada

Keyword(s):

Blood Pressure ◽

Oleanolic Acid ◽

Ex Vivo ◽

Biological Activities ◽

Cardiovascular Prevention ◽

In Vivo Studies ◽

Antihypertensive Activity ◽

In Vitro Tests

Background:: Hypertension is a high prevalent chronic disease worldwide and a major cardiovascular risk factor. Oleanolic acid (3β-hydroxy-olea-12-en-28-oic acid) is a wide distributed bioactive pentacyclic triterpenoid with diverse biological activities such as anti-inflammatory, hepaprotective anti-diabetic or anti-hypertensive. Objective:: The aim of this study was to review and highlight the available data about antihypertensive activity of oleanolic acid and the described mechanisms of action. Method:: Extensive searches were made in the available literature on oleanolic acid and the data investigating its antihypertensive effects were analysed. Results:: Most of research has been performed on animal models of hypertension, ex vivo studies with aortic ring and some in vitro tests with cell cultures, whereas clinical trials are still lacking. Treatment of hypertensive animals with oleanolic acid significantly ameliorated the rise in the systolic blood pressure. In addition, the hypotensive effects of oleanolic acid are also related to a potent diuretic-natriuretic activity and nephroprotection. In vitro studies have characterized the participation of various signalling pathways that modulate the release of vasodilation mediators. Conclusion:: In vitro and in vivo studies suggest that oleanolic acid effectively reduce blood pressure and could be an interesting co-adjuvant to conventional treatment of hypertension.

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Factor VLEIDEN and cardiopulmonary bypass: investigation of haemostatic parameters and the effect of aprotinin using an ex vivo model

Perfusion ◽

10.1177/026765910101600607 ◽

2001 ◽

Vol 16 (6) ◽

pp. 476-484 ◽

Cited By ~ 5

Author(s):

M D Linden ◽

M Schneider ◽

W N Erber

Keyword(s):

Cardiopulmonary Bypass ◽

Extracorporeal Circulation ◽

Ex Vivo ◽

Normal Blood ◽

Factor V ◽

Ex Vivo Model ◽

Haemostatic Agents ◽

Increased Risk

It has been suggested that aprotinin results in significantly increased risk for perioperative thrombotic complications in patients with Factor VLEIDEN (F5L) due to its ability to competitively inhibit activated protein C (APC) function in vitro. No clinical studies have been performed to assess the effect of aprotinin on APC function of F5L in vivo. We developed an ex vivo model to mimic the effects of cardiopulmonary bypass with the exclusion of the patient in order to assess APC function. Blood from normal ( n = 2) and F5L heterozygous donors ( n = 2) was treated with aprotinin or placebo (saline). The blood was heparinized, added to the prime and circulated at 2 l/min through a modified cardiopulmonary bypass circuit. After 60 min of circulation, the heparin was neutralized with protamine sulfate. Blood samples, drawn at specific time points, were analysed for APC ratio. Results showed a decrease in APC ratio for both F5L and normal bloods with the addition of aprotinin (18% and 40%, respectively). APC ratios also decreased with the commencement of extracorporeal circulation for all bloods, resulting in an APC ratio of 1.35 in normal placebo-treated blood and 0.67 in F5L placebo-treated blood. The combined effect of aprotinin and extracorporeal circulation resulted in APC ratios of 0.90 for normal blood and 0.63 for F5L blood, corresponding to a severe dysfunction of APC intraoperatively (reference range 1.9-4.0). The data from this model predict an increased risk of perioperative thrombosis due to inhibition of APC function in cardiac surgical patients heterozygous for the F5L mutation. Aprotinin further compounds the severity of APC dysfunction, though the effect is more severe in normal blood. The ex vivo model employed was an effective tool for the investigation of the haemostatic effect of aprotinin. This model may be exploited for other applications such as the investigation of novel or emerging haemostatic agents prior to clinical trial.

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Dissolving Microneedles for Intradermal Vaccination against Shigellosis

Vaccines ◽

10.3390/vaccines7040159 ◽

2019 ◽

Vol 7 (4) ◽

pp. 159 ◽

Cited By ~ 4

Author(s):

Pastor ◽

Larrañeta ◽

Erhard ◽

Quincooces ◽

Peñuelas ◽

...

Keyword(s):

Outer Membrane ◽

Ex Vivo ◽

Membrane Vesicle ◽

Outer Membrane Vesicles ◽

Ex Vivo Model ◽

Intradermal Vaccination ◽

Dissolving Microneedles ◽

Biodistribution Studies

Intradermal (ID) immunization is of increasing interest due to the easy accessibility and excellent immunogenic properties of the skin. Among ID immunization methods, dissolving microneedles (MNs) have appeared as an alternative to traditional hypodermic immunization, offering many advantages, such as being an easily administered method, with no need for health personnel, painless, and avoiding the use of needles and sharp wastage. In this study, an affordable and easy-to-produce MNs method was developed based on aqueous blends of 30% w/w poly (methyl vinyl ether-co-maleic anhydride). As an antigen model, a subunit vaccine candidate based on outer membrane vesicles from Shigella flexneri was used. Both unloaded and antigen-loaded MNs were synthetized and characterized. The MNs were successfully validated in an in vitro Parafilm M® skin model and in a pig skin ex vivo model. Biodistribution studies were performed in BALB/c mice using 99mTcO4- radiolabeled samples. Results indicated that the vesicle vaccine was successfully released from the MNs and targeted gastrointestinal tract after 6 h post-administration. In vivo immunization and protection studies were performed in BALB/c mice. Mice were intradermally immunized through ear skin with one single dose of 200 g antigenic complex, eliciting the production of specific systemic IgG and mucosal IgA. Moreover, MNs were able to protect mice from an experimental infection with 1×106 CFU/mouse of S. flexneri four weeks after immunization. This work demonstrates for the first time the potential of outer membrane vesicle-loaded dissolving MNs for ID vaccination against enteropathogens like Shigella.

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A Combined Phenotypic-Genotypic Predictive Algorithm for In Vitro Detection of Bicarbonate: β-Lactam Sensitization among Methicillin-Resistant Staphylococcus aureus (MRSA)

Antibiotics ◽

10.3390/antibiotics10091089 ◽

2021 ◽

Vol 10 (9) ◽

pp. 1089

Author(s):

Selvi C. Ersoy ◽

Warren E. Rose ◽

Robin Patel ◽

Richard A. Proctor ◽

Henry F. Chambers ◽

...

Keyword(s):

Susceptibility Testing ◽

Genomic Sequence ◽

Ex Vivo ◽

Coding Region ◽

Ex Vivo Model ◽

In Vitro Susceptibility ◽

Predictive Algorithm ◽

Mrsa Strains

Antimicrobial susceptibility testing (AST) is routinely used to establish predictive antibiotic resistance metrics to guide the treatment of bacterial pathogens. Recently, a novel phenotype termed “bicarbonate (NaHCO3)-responsiveness” was identified in a relatively high frequency of clinical MRSA strains, wherein isolates demonstrate in vitro “susceptibility” to standard β-lactams (oxacillin [OXA]; cefazolin [CFZ]) in the presence of NaHCO3, and in vivo susceptibility to these β-lactams in experimental endocarditis models. We investigated whether a targeted phenotypic-genotypic screening of MRSA could rule in or rule out NaHCO3 susceptibility upfront. We studied 30 well-characterized clinical MRSA bloodstream isolates, including 15 MIC-susceptible to CFZ and OXA in NaHCO3-supplemented Mueller–Hinton Broth (MHB); and 15 MIC-resistant to both β-lactams in this media. Using a two-tiered strategy, isolates were first screened by standard disk diffusion for susceptibility to a combination of amoxicillin-clavulanate [AMC]. Isolates then underwent genomic sequence typing: MLST (clonal complex [CC]); agr; SCCmec; and mecA promoter and coding region. The combination of AMC disk susceptibility testing plus mecA and spa genotyping was able to predict MRSA strains that were more or less likely to be NaHCO3-responsive in vitro, with a high degree of sensitivity and specificity. Validation of this screening algorithm was performed in six strains from the overall cohort using an ex vivo model of endocarditis. This ex vivo model recapitulated the in vitro predictions of NaHCO3-responsiveness vs. nonresponsiveness above in five of the six strains.

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Hydrothermal Treatment Enhances Antioxidant Activity and Intestinal Absorption of Rutin in Tartary Buckwheat Flour Extracts

Foods ◽

10.3390/foods9010008 ◽

2019 ◽

Vol 9 (1) ◽

pp. 8 ◽

Cited By ~ 4

Author(s):

Hye-Rin Jin ◽

Jin Yu ◽

Soo-Jin Choi

Keyword(s):

Antioxidant Activity ◽

Intestinal Absorption ◽

Food Industry ◽

Ex Vivo ◽

Radical Scavenging ◽

Tartary Buckwheat ◽

Ex Vivo Model ◽

Wide Range ◽

Buckwheat Flour

Tartary buckwheat (Fagopyrum esculentum) is widely used in the food industry due to its functionality, which is related to its high rutin content. However, rutin is easily converted into quercetin by an endogenous enzyme during processing, resulting in a bitter taste. In this study, rutin-enriched Tartary buckwheat flour extracts (TBFEs) were obtained by hydrothermal treatments (autoclaving, boiling, and steaming), and their antioxidant activity was evaluated in human intestinal cells. The intestinal absorption of the hydrothermally treated TBFEs was also investigated using in vitro models of intestinal barriers and an ex vivo model of intestinal absorption. The results demonstrated that all of the hydrothermally treated TBFEs had increased rutin, total polyphenol, and total flavonoid contents, which enhance the in vitro and intracellular radical scavenging activities. Antioxidant enzyme activity, cellular uptake efficiency, in vitro intestinal transport efficacy, and ex vivo intestinal absorption of the hydrothermally treated TBFEs were also enhanced compared with those of native TBFE or standard rutin. These findings suggest the promising potential of hydrothermally treated TBFEs for a wide range of applications in the functional food industry.

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