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3.
Inhal Toxicol ; 35(11-12): 271-284, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37853720

RESUMO

OBJECTIVES: An integrated in vitro inhalation approach was outlined to estimate potential adverse acute inhalation effects of aerosols from commercial nebulizer applications used for purposeful room conditioning such as disinfection, scenting or others. Aerosol characterization, exposure estimation and evaluation of acute biological effects by in vitro inhalation were included to generate dose-response data, allowing for determination of in vitro lowest observable adverse effect levels (LOAELs). Correlation of these to estimates of human lung deposition was included for quantitative in vitro to in vivo extrapolation approach (QIVIVE) for acute effects during human exposure. METHODS: To test the proposed approach, a case study was undertaken using two realistic test materials. An acute in vitro inhalation setup with air-liquid interface A549-cells in an optimized exposure situation (P.R.I.T.® ExpoCube®) was used to expose cells and analysis of relevant biological effects (viability, mitochondrial membrane potential, stress, IL-8 release) was carried out. RESULTS: The observed dose-responsive effects in a sub-toxic dose-range could be attributed to the main component of one test material and its presence in the aerosol phase of the nebulized material. QIVIVE resulted in a factor of at least 256 between the in vitro LOAEL and the estimated acute human lung exposure for this test material. CONCLUSIONS: The case-study shows the value of the non-target in vitro inhalation testing approach especially in case of a lack of knowledge on complex product composition. It is expected that approaches like this will be of high value for product safety and environmental health in the future.


Design of a routine in vitro inhalation approach to estimate biological effects of nebulized products.Application in a case study on a potential real product for purposeful room conditioning by use of a commercial nebulizer.Combining results from aerosol characterization and in vitro inhalation experiments allowed for comprehensive correlation of product composition, aerosol properties and biological effects.Assignment of sub-toxic biological effects to a specific product component enabled identification of a product composition with potentially even less biological effect.Combined in vivo exposure estimation and in vitro LOAEL determination enabled a QIVIVE approach.


Assuntos
Pulmão , Nebulizadores e Vaporizadores , Humanos , Aerossóis , Administração por Inalação
4.
J. optom. (Internet) ; 16(3): 210-220, July - September 2023. graf, tab
Artigo em Inglês | IBECS | ID: ibc-222230

RESUMO

Purpose To describe the prevalence and severity of photosensitivity in patients with albinism, and to compare with ocular features and how this correlated with use and choice of optical filters. Methods Cross-sectional study on 81 participants with ocular or oculocutaneous albinism. An ophthalmic evaluation including visual acuity, contrast sensitivity and evaluation of iris translucency and fundus hypopigmentation was performed. Participants were offered optical rehabilitation with testing of a wide panel of filters. The associations between ocular characteristics, subjective photosensitivity complaints, and filter choice were evaluated. Results Photosensitivity was rated as “some” to “worst imaginable” in 77.8% of participants. Severity of photosensitivity correlated significantly with fundus hypopigmentation (p = 0.04) but not with iris translucency (p = 0.14) and it was worse in those with poor visual acuity but there was no association between photosensitivity and contrast vision. Seventy-four new pairs of spectacles were prescribed in the study. All outdoor spectacles contained a filter, whereas 26.5% of new indoor spectacles did not. Relatively neutral filter colors (gray, brown or a combination of gray and brown with other colors) and low transmission were preferred. Discussion Photosensitivity is common in albinism, but research targeting treatment is limited. Color and neutral filters with a low light transmission were preferred, with participants having a large number of spectacles, presumably to meet their needs in different situations. (AU)


Assuntos
Albinismo , Fármacos Fotossensibilizantes
5.
Clin Res Hepatol Gastroenterol ; 47(7): 102159, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37307949

RESUMO

BACKGROUND: In the North Denmark Region an increased awareness of eosinophilic esophagitis (EoE) was observed after 2011 where a regional biopsy guideline was implemented. This resulted in an increased awareness of EoE and a 50-fold increase in the incidence of EoE patients between 2007-2017. AIMS: The aims of this study were to examine the progress in diagnostic delay, complications, PPI treatment, and follow up since 2017 in Danish patients with eosinophilic esophagitis. MATERIALS AND METHODS: This was a retrospective registry- and population-based cohort study (DanEoE2 cohort) including 346 adult patients with esophageal eosinophilia diagnosed between 2018-2021 in the North Denmark Region. The DanEoE2 cohort included all possible EoE patients by using the Danish Patho-histology registry based on the SNOMED-system. The data was analyzed and compared to the DanEoE cohort (2007-2017). RESULTS: The diagnostic delay of EoE patients diagnosed between 2018-2021 in the North Denmark Region had decreased with a median of 1.5 years (5.5 (2.0;12) years versus 4.0 (1.0;12) years, p=0.03). Strictures before diagnosis had decreased 8.4 % (11.6% versus 3.2%, p=0.003). The number of patients started on high-dose PPI increased (56% versus 88%, p<0.001). An intensified awareness regarding national guidelines and follow-up was observed as an increase in the number of histological follow up (67% versus 74%, p=0.05). CONCLUSIONS: Comparisons of the DanEoE cohorts showed a decrease in diagnostic delay, a decrease in stricture formation before diagnosis, and an improved guideline adherence after 2017. Future studies are needed to assess if symptomatic or histological remission on PPI treatment is more capable of predicting a patient's risk of developing complications.


Assuntos
Esofagite Eosinofílica , Adulto , Humanos , Esofagite Eosinofílica/diagnóstico , Esofagite Eosinofílica/tratamento farmacológico , Esofagite Eosinofílica/epidemiologia , Constrição Patológica , Diagnóstico Tardio/efeitos adversos , Estudos Retrospectivos , Estudos de Coortes , Fidelidade a Diretrizes , Inibidores da Bomba de Prótons/uso terapêutico , Dinamarca/epidemiologia
6.
Environ Toxicol Pharmacol ; 100: 104139, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37142072

RESUMO

Occupational exposure to veterinary antibiotics in hen houses at poultry feeding farms was demonstrated by biomonitoring campaigns in the past. The objective of this study was to investigate pharmacokinetics of three uptake routes: dermal, oral and inhaled. In an open-label cross-over study, six healthy volunteers were exposed to single occupational relevant doses of enrofloxacin. Plasma and urine samples were analysed for enrofloxacin and ciprofloxacin. Physiologically based pharmacokinetic (PBPK) modelling based on bioanalysis data showed underestimation for the elimination rate in comparison to experimental data pointing towards a lack of sufficient ADME information and limitations of available physico-chemical properties of the parent drug. The data obtained in this study indicate that oral uptake with its various sources, e.g. airborne enrofloxacin, direct hand-mouth contact, is the major source for occupational exposure to enrofloxacin in hen houses. Dermal exposure was considered negligible.


Assuntos
Antibacterianos , Exposição Ocupacional , Humanos , Ciprofloxacina , Estudos Cross-Over , Enrofloxacina
7.
Front Toxicol ; 5: 1155645, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37206915

RESUMO

This case study explores the applicability of transcriptome data to characterize a common mechanism of action within groups of short-chain aliphatic α-, ß-, and γ-diketones. Human reference in vivo data indicate that the α-diketone diacetyl induces bronchiolitis obliterans in workers involved in the preparation of microwave popcorn. The other three α-diketones induced inflammatory responses in preclinical in vivo animal studies, whereas beta and gamma diketones in addition caused neuronal effects. We investigated early transcriptional responses in primary human bronchiolar (PBEC) cell cultures after 24 h and 72 h of air-liquid exposure. Differentially expressed genes (DEGs) were assessed based on transcriptome data generated with the EUToxRisk gene panel of Temp-O-Seq®. For each individual substance, genes were identified displaying a consistent differential expression across dose and exposure duration. The log fold change values of the DEG profiles indicate that α- and ß-diketones are more active compared to γ-diketones. α-diketones in particular showed a highly concordant expression pattern, which may serve as a first indication of the shared mode of action. In order to gain a better mechanistic understanding, the resultant DEGs were submitted to a pathway analysis using ConsensusPathDB. The four α-diketones showed very similar results with regard to the number of activated and shared pathways. Overall, the number of signaling pathways decreased from α-to ß-to γ-diketones. Additionally, we reconstructed networks of genes that interact with one another and are associated with different adverse outcomes such as fibrosis, inflammation or apoptosis using the TRANSPATH-database. Transcription factor enrichment and upstream analyses with the geneXplain platform revealed highly interacting gene products (called master regulators, MRs) per case study compound. The mapping of the resultant MRs on the reconstructed networks, visualized similar gene regulation with regard to fibrosis, inflammation and apoptosis. This analysis showed that transcriptome data can strengthen the similarity assessment of compounds, which is of particular importance, e.g., in read-across approaches. It is one important step towards grouping of compounds based on biological profiles.

8.
J Optom ; 16(3): 214-220, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36028395

RESUMO

PURPOSE: To describe the prevalence and severity of photosensitivity in patients with albinism, and to compare with ocular features and how this correlated with use and choice of optical filters. METHODS: Cross-sectional study on 81 participants with ocular or oculocutaneous albinism. An ophthalmic evaluation including visual acuity, contrast sensitivity and evaluation of iris translucency and fundus hypopigmentation was performed. Participants were offered optical rehabilitation with testing of a wide panel of filters. The associations between ocular characteristics, subjective photosensitivity complaints, and filter choice were evaluated. RESULTS: Photosensitivity was rated as "some" to "worst imaginable" in 77.8% of participants. Severity of photosensitivity correlated significantly with fundus hypopigmentation (p = 0.04) but not with iris translucency (p = 0.14) and it was worse in those with poor visual acuity but there was no association between photosensitivity and contrast vision. Seventy-four new pairs of spectacles were prescribed in the study. All outdoor spectacles contained a filter, whereas 26.5% of new indoor spectacles did not. Relatively neutral filter colors (gray, brown or a combination of gray and brown with other colors) and low transmission were preferred. DISCUSSION: Photosensitivity is common in albinism, but research targeting treatment is limited. Color and neutral filters with a low light transmission were preferred, with participants having a large number of spectacles, presumably to meet their needs in different situations.


Assuntos
Albinismo Oculocutâneo , Albinismo , Humanos , Estudos Transversais , Albinismo/complicações , Albinismo Oculocutâneo/epidemiologia , Albinismo Oculocutâneo/complicações , Visão Ocular , Acuidade Visual
9.
Cancers (Basel) ; 14(2)2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35053588

RESUMO

Although therapeutic options are gradually improving, the overall prognosis for patients with hepatocellular carcinoma (HCC) is still poor. Gene therapy-based strategies are developed to complement the therapeutic armamentarium, both in early and late-stage disease. For efficient delivery of transgenes with antitumor activity, vectors demonstrating preferred tumor tropism are required. Here, we report on the natural tropism of adeno-associated virus (AAV) serotype 2 vectors for HCC. When applied intravenously in transgenic HCC mouse models, similar amounts of vectors were detected in the liver and liver tumor tissue. In contrast, transduction efficiency, as indicated by the level of transgene product, was moderate in the liver but was elevated up to 19-fold in mouse tumor tissue. Preferred transduction of HCC compared to hepatocytes was confirmed in precision-cut liver slices from human patient samples. Our mechanistic studies revealed that this preference is due to the improved intracellular processing of AAV2 vectors in HCC, resulting, for example, in nearly 4-fold more AAV vector episomes that serve as templates for gene transcription. Given this background, AAV2 vectors ought to be considered to strengthen current-or develop novel-strategies for treating HCC.

10.
BMC Res Notes ; 14(1): 255, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215333

RESUMO

OBJECTIVE: Human precision cut lung slices (PCLS) are widely used as an ex vivo model system for drug discovery and development of new therapies. PCLS reflect the functional heterogeneity of lung tissue and possess relevant lung cell types. We thus determined the use of PCLS in studying non-coding RNAs notably miRNAs, which are important gene regulatory molecules. Since miRNAs play key role as mediators of respiratory diseases, they can serve as valuable prognostic or diagnostic biomarkers, and in therapeutic interventions, of lung diseases. A technical limitation though is the vast amount of agarose in PCLS which impedes (mi)RNA extraction by standard procedures. Here we modified our recently published protocol for RNA isolation from PCLS to enable miRNA readouts. RESULTS: The modified method relies on the separation of lysis and precipitation steps, and a clean-up procedure with specific magnetic beads. We obtained successfully quality miRNA amenable for downstream applications such as RTqPCR and whole transcriptome miRNA analysis. Comparison of miRNA profiles in PCLS with published data from human lung, identified all important miRNAs regulated in IPF, COPD, asthma or lung cancer. Therefore, this shows suitability of the method for analyzing miRNA targets and biomarkers in the valuable human PCLS model.


Assuntos
Pneumopatias , Neoplasias Pulmonares , MicroRNAs , Perfilação da Expressão Gênica , Humanos , Pulmão
11.
Arch Toxicol ; 95(2): 573-589, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33106934

RESUMO

The liver plays an important role in xenobiotic metabolism and represents a primary target for toxic substances. Many different in vitro cell models have been developed in the past decades. In this study, we used RNA-sequencing (RNA-Seq) to analyze the following human in vitro liver cell models in comparison to human liver tissue: cancer-derived cell lines (HepG2, HepaRG 3D), induced pluripotent stem cell-derived hepatocyte-like cells (iPSC-HLCs), cancerous human liver-derived assays (hPCLiS, human precision cut liver slices), non-cancerous human liver-derived assays (PHH, primary human hepatocytes) and 3D liver microtissues. First, using CellNet, we analyzed whether these liver in vitro cell models were indeed classified as liver, based on their baseline expression profile and gene regulatory networks (GRN). More comprehensive analyses using non-differentially expressed genes (non-DEGs) and differential transcript usage (DTU) were applied to assess the coverage for important liver pathways. Through different analyses, we noticed that 3D liver microtissues exhibited a high similarity with in vivo liver, in terms of CellNet (C/T score: 0.98), non-DEGs (10,363) and pathway coverage (highest for 19 out of 20 liver specific pathways shown) at the beginning of the incubation period (0 h) followed by a decrease during long-term incubation for 168 and 336 h. PHH also showed a high degree of similarity with human liver tissue and allowed stable conditions for a short-term cultivation period of 24 h. Using the same metrics, HepG2 cells illustrated the lowest similarity (C/T: 0.51, non-DEGs: 5623, and pathways coverage: least for 7 out of 20) with human liver tissue. The HepG2 are widely used in hepatotoxicity studies, however, due to their lower similarity, they should be used with caution. HepaRG models, iPSC-HLCs, and hPCLiS ranged clearly behind microtissues and PHH but showed higher similarity to human liver tissue than HepG2 cells. In conclusion, this study offers a resource of RNA-Seq data of several biological replicates of human liver cell models in vitro compared to human liver tissue.


Assuntos
Biologia Computacional/métodos , Hepatócitos/metabolismo , Neoplasias Hepáticas/metabolismo , Fígado/metabolismo , Transcriptoma , Diferenciação Celular , Linhagem Celular Tumoral , Células Cultivadas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Células Hep G2 , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Técnicas In Vitro , Células-Tronco Pluripotentes Induzidas/metabolismo , Modelos Biológicos , RNA-Seq
12.
Toxicol In Vitro ; 63: 104714, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31706036

RESUMO

Due to the increasing need of new treatment options against bacterial lung infections, novel antimicrobial peptides (AMPs) are under development. Local bioavailability and less systemic exposure lead to the inhalation route of administration. Combining AMPs with nanocarriers (NCs) into nanosystems (NSs) might be a technique for improved results. An air-liquid interface (ALI) in vitro inhalation model was set up including a human alveolar lung cell line (A549) and an optimized exposure system (P.R.I.T.® ExpoCube®) to predict acute local lung toxicity. The approach including aerosol controls (cupper-II-sulfate and lactose) delivered lowest observable adverse effect levels (LOAELs). Different combinations of AMPs (AA139, M33) and NCs (polymeric nanoparticles (PNPs), micelles and liposomes) were tested under ALI and submerged in vitro conditions. Depending on the nature of AMP and NCs, packing of AMPs into NSs reduced the AMP-related toxicity. Large differences were found between the LOAELs determined by submerged or ALI testing with the ALI approach indicating higher sensitivity of the ALI model. Since aerosol droplet exposure is in vivo relevant, it is assumed that ALI based results represents the more significant source than submerged testing for in vivo prediction of local acute lung toxicity. In accordance with the current state-of-the-art view, this study shows that ALI in vitro inhalation models are promising tools to further develop in vitro methods in the field of inhalation toxicology.


Assuntos
Antibacterianos/toxicidade , Nanopartículas/toxicidade , Peptídeos/toxicidade , Células A549 , Aerossóis , Antibacterianos/administração & dosagem , Infecções Bacterianas/tratamento farmacológico , Sobrevivência Celular/efeitos dos fármacos , Humanos , Lipossomos , Pulmão/efeitos dos fármacos , Pneumopatias/tratamento farmacológico , Metacrilatos/administração & dosagem , Metacrilatos/toxicidade , Micelas , Nanopartículas/administração & dosagem , Nylons/toxicidade , Peptídeos/administração & dosagem
13.
Toxicol In Vitro ; 60: 12-18, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30910522

RESUMO

The cytotoxicity of two different types of Multi-walled Carbon Nanotubes (MWCNTs) in A549 lung epithelial cells and HepG2 hepatocytes was investigated. One MWCNT still contained iron that was used as a catalyst during production, while the other one had all iron removed in a post-production heat treatment resulting in significantly fewer surface defects. The WST-8 assay was applied to test cell viability. To check the integrity of the cell membrane, we performed the lactate dehydrogenases assay (LDH) and measured the cellular production of reactive oxygen species (ROS). Finally, to examine cell proliferation, we conducted a cell cycle analysis. The results showed a dose- and time-dependent decrease in cell viability for both MWCNTs in both cell types. Moreover, a dose- and time-dependent increase in LDH leakage was detected, thereby indicating a decreased membrane integrity. The production of ROS was significantly increased in the case of the heat-treated MWCNTs. The heat-treated MWCNTs showed significantly stronger adverse effects when compared to the non-treated MWCNTs. Additionally, the heat-treated MWCNTs induced a dose-dependent cell cycle arrest in A549 cells. Both MWCNTs induced a significant cytotoxicity, whereby the heat treatment, leading to a decrease in surface defects, further increased the indicated adverse effects.


Assuntos
Nanotubos de Carbono/toxicidade , Células A549 , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Hep G2 , Humanos , L-Lactato Desidrogenase/metabolismo , Nanotubos de Carbono/química , Espécies Reativas de Oxigênio/metabolismo , Propriedades de Superfície
14.
Nanomaterials (Basel) ; 8(4)2018 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-29614747

RESUMO

Exposure to exogenous noxae, such as particulate matter, can trigger acute aggravations of allergic asthma-a chronic inflammatory airway disease. We tested whether Carbon Black nanoparticles (CBNP) with or without surface polycyclic aromatic hydrocarbons (PAH) aggravate an established allergic airway inflammation in mice. In an ovalbumin mouse model, Printex®90 (P90), P90 coated with benzo[a]pyrene (P90-BaP) or 9-nitroanthracene (P90-9NA), or acetylene soot exhibiting a mixture of surface PAH (AS-PAH) was administered twice (70 µL, 100 µg/mL) during an established allergic airway inflammation. We analyzed the immune cell numbers and chemokine/cytokine profiles in bronchoalveolar lavages, the mRNA expressions of markers for PAH metabolism (Cyp1a1, 1b1), oxidative stress (HO-1, Gr, Gpx-3), inflammation (KC, Mcp-1, IL-6, IL-13, IL-17a), mucin synthesis (Muc5ac, Muc5b), the histology of mucus-producing goblet cells, ciliary beat frequency (CBF), and the particle transport speed. CBNP had a comparable primary particle size, hydrodynamic diameter, and ζ-potential, but differed in the specific surface area (P90 > P90-BaP = P90-9NA = AS-PAH) and surface chemistry. None of the CBNP tested increased any parameter related to inflammation. The unmodified P90, however, decreased the tracheal CBF, decreased the Muc5b in intrapulmonary airways, but increased the tracheal Muc5ac. Our results demonstrated that irrespective of the surface PAH, a low dose of CBNP does not acutely aggravate an established allergic airway inflammation in mice.

15.
J Nanobiotechnology ; 16(1): 16, 2018 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-29463257

RESUMO

BACKGROUND: Understanding the molecular mechanisms of nanomaterial interacting with cellular systems is important for appropriate risk assessment. The identification of early biomarkers for potential (sub-)chronic effects of nanoparticles provides a promising approach towards cost-intensive and animal consuming long-term studies. As part of a 90-day inhalation toxicity study with CeO2 NM-212 and BaSO4 NM-220 the present investigations on gene expression and immunohistochemistry should reveal details on underlying mechanisms of pulmonary effects. The role of alveolar epithelial cells type II (AEII cells) is focused since its contribution to defense against inhaled particles and potentially resulting adverse effects is assumed. Low dose levels should help to specify particle-related events, including inflammation and oxidative stress. RESULTS: Rats were exposed to clean air, 0.1, 0.3, 1.0, and 3.0 mg/m3 CeO2 NM-212 or 50.0 mg/m3 BaSO4 NM-220 and the expression of 391 genes was analyzed in AEII cells after one, 28 and 90 days exposure. A total number of 34 genes was regulated, most of them related to inflammatory mediators. Marked changes in gene expression were measured for Ccl2, Ccl7, Ccl17, Ccl22, Ccl3, Ccl4, Il-1α, Il-1ß, and Il-1rn (inflammation), Lpo and Noxo1 (oxidative stress), and Mmp12 (inflammation/lung cancer). Genes related to genotoxicity and apoptosis did not display marked regulation. Although gene expression was less affected by BaSO4 compared to CeO2 the gene pattern showed great overlap. Gene expression was further analyzed in liver and kidney tissue showing inflammatory responses in both organs and marked downregulation of oxidative stress related genes in the kidney. Increases in the amount of Ce were measured in liver but not in kidney tissue. Investigation of selected genes on protein level revealed increased Ccl2 in bronchoalveolar lavage of exposed animals and increased Lpo and Mmp12 in the alveolar epithelia. CONCLUSION: AEII cells contribute to CeO2 nanoparticle caused inflammatory and oxidative stress reactions in the respiratory tract by the release of related mediators. Effects of BaSO4 exposure are low. However, overlap between both substances were detected and support identification of potential early biomarkers for nanoparticle effects on the respiratory system. Signs for long-term effects need to be further evaluated by comparison to a respective exposure setting.


Assuntos
Células Epiteliais Alveolares/efeitos dos fármacos , Sulfato de Bário/efeitos adversos , Cério/efeitos adversos , Regulação da Expressão Gênica/efeitos dos fármacos , Exposição por Inalação/efeitos adversos , Nanopartículas/efeitos adversos , Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/patologia , Animais , Apoptose/efeitos dos fármacos , Sulfato de Bário/administração & dosagem , Células Cultivadas , Cério/administração & dosagem , Reparo do DNA/efeitos dos fármacos , Feminino , Inflamação/induzido quimicamente , Inflamação/genética , Inflamação/patologia , Nanopartículas/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Ratos Wistar
16.
Toxicol Rep ; 4: 89-103, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28959630

RESUMO

Interactions between hepatocytes and immune cells as well as inflammatory episodes are frequently discussed to play a critical role in the alteration of the individual susceptibility to idiosyncratic drug-induced liver injury (iDILI). To evaluate this hypothesis and to face the urgent need for predictive in vitro models, we established two co-culture systems based on two human cell lines in presence or absence of pro-inflammatory factors (LPS, TNF), i.e. hepatoma HepG2 cells co-cultured with monocytic or macrophage-like THP-1 cells. HepG2 monocultures served as control scenario. Mono- or co-cultures were treated with iDILI reference substances (Troglitazone [TGZ], Trovafloxacin [TVX], Diclofenac [DcL], Ketoconazole [KC]) or their non-iDILI partner compounds (Rosiglitazone, Levofloxacin, Acetylsalicylic Acid, Fluconazole). The liver cell viability was subsequently determined via WST-Assay. An enhanced cytotoxicity (synergy) or a hormetic response compared to the drug effect in the HepG2 monoculture was considered as iDILI positive. TGZ synergized in co-cultures with monocytes without an additional pro-inflammatory stimulus, while DcL and KC showed a hormetic response. All iDILI drugs synergized with TNF in the simple HepG2 monoculture, indicating its relevance as an initiator of iDILI. KC showed a synergy when co-exposed to both, monocytes and LPS, while TVX and DcL showed a synergy under the same conditions with macrophages. All described iDILI responses were not observed with the corresponding non-iDILI partner compounds. Our first results confirm that an inflammatory environment increases the sensitivity of liver cells towards iDILI compounds and point to an involvement of pro-inflammatory factors, especially TNF, in the development of iDILI.

17.
Toxicol In Vitro ; 42: 200-213, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28476500

RESUMO

Precision cut liver slices (PCLiS) represent a promising tool in reflecting hepatotoxic responses. However, the culture of PCLiS varies considerably between laboratories, which can affect the performance of the liver slices and thus the experimental outcome. In this study, we describe an easily accessible culture method, which ensures optimal slice viability and functionality, in order to set the basis for reproducible and comparable PCLiS studies. The quality of the incubated rat PCLiS was assessed during a 24h culture period using ten readouts, which covered viability (lactate dehydrogenase-, aspartate transaminase- and glutamate dehydrogenase-leakage, ATP content) and functionality parameters (urea, albumin production) as well as histomorphology and other descriptive characteristics (protein content, wet weight, slice thickness). The present culture method resulted in high quality liver slices for 24h. Finally, PCLiS were exposed to increasing concentrations of acetaminophen to assess the suitability of the model for the detection of hepatotoxic responses. Six out of ten readouts revealed a toxic effect and showed an excellent mutual correlation. ATP, albumin and histomorphology measurements were identified as the most sensitive readouts. In conclusion, our results indicate that rat PCLiS are a valuable liver model for hepatotoxicity studies, particularly if they are cultured under optimal standardized conditions.


Assuntos
Acetaminofen/toxicidade , Fígado/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Albuminas/metabolismo , Animais , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Fígado/metabolismo , Fígado/patologia , Masculino , Modelos Biológicos , Técnicas de Cultura de Órgãos , Ratos Wistar , Ureia/metabolismo
18.
Part Fibre Toxicol ; 14(1): 8, 2017 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-28327162

RESUMO

BACKGROUND: Carbon black nanoparticles (CBNP) are mainly composed of carbon, with a small amount of other elements (including hydrogen and oxygen). The toxicity of CBNP has been attributed to their large surface area, and through adsorbing intrinsically toxic substances, such as polycyclic aromatic hydrocarbons (PAH). It is not clear whether a PAH surface coating changes the toxicological properties of CBNP by influencing their physicochemical properties, through the specific toxicity of the surface-bound PAH, or by a combination of both. METHODS: Printex®90 (P90) was used as CBNP; the comparators were P90 coated with either benzo[a]pyrene (BaP) or 9-nitroanthracene (9NA), and soot from acetylene combustion that bears various PAHs on the surface (AS-PAH). Oxidative stress and IL-8/KC mRNA expression were determined in A549 and bronchial epithelial cells (16HBE14o-, Calu-3), mouse intrapulmonary airways and tracheal epithelial cells. Overall toxicity was tested in a rat inhalation study according to Organization for Economic Co-operation and Development (OECD) criteria. Effects on cytochrome monooxygenase (Cyp) mRNA expression, cell viability and mucociliary clearance were determined in acute exposure models using explanted murine trachea. RESULTS: All particles had similar primary particle size, shape, hydrodynamic diameter and ζ-potential. All PAH-containing particles had a comparable specific surface area that was approximately one third that of P90. AS-PAH contained a mixture of PAH with expected higher toxicity than BaP or 9NA. PAH-coating reduced some effects of P90 such as IL-8 mRNA expression and oxidative stress in A549 cells, granulocyte influx in the in vivo OECD experiment, and agglomeration of P90 and mucus release in the murine trachea ex vivo. Furthermore, P90-BaP decreased particle transport speed compared to P90 at 10 µg/ml. In contrast, PAH-coating induced IL-8 mRNA expression in bronchial epithelial cell lines, and Cyp mRNA expression and apoptosis in tracheal epithelial cells. In line with the higher toxicity compared to P90-BaP and P90-9NA, AS-PAH had the strongest biological effects both ex vivo and in vivo. CONCLUSIONS: Our results demonstrate that the biological effect of CBNP is determined by a combination of specific surface area and surface-bound PAH, and varies in different target cells.


Assuntos
Células Epiteliais/efeitos dos fármacos , Nanopartículas/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Fuligem/toxicidade , Células A549 , Animais , Apoptose/efeitos dos fármacos , Células Epiteliais/metabolismo , Feminino , Humanos , Imunidade Inata/efeitos dos fármacos , Exposição por Inalação , Interleucina-8/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Masculino , Camundongos Endogâmicos BALB C , Nanopartículas/química , Tamanho da Partícula , Hidrocarbonetos Policíclicos Aromáticos/química , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Fuligem/química , Propriedades de Superfície , Traqueia/efeitos dos fármacos , Traqueia/patologia
19.
BMC Res Notes ; 10(1): 121, 2017 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-28274266

RESUMO

BACKGROUND: Functional 3D organ models such as precision-cut lung slices (PCLS) have recently captured the attention of biomedical research. To enable wider implementation in research and development, these new biologically relevant organ models are being constantly refined. A very important issue is to improve the preparation of high-quality RNA (ribonucleic acid) from PCLS for drug discovery and development of new therapies. Gene expression analysis at different levels is used as an important experimental readout. Genome-wide analysis using microarrays is mostly applied for biomarker selection in disease models or in comprehensive toxicological studies. Specific biomarker testing by reverse transcriptase quantitative polymerase chain reaction (RTqPCR) is often used in efficacy studies. Both applications require high-quality RNA as starting material for the generation of reliable data. Additionally, a small number of slices should be sufficient for satisfactory RNA isolation to allow as many experimental conditions as possible to be covered with a given tissue sample. Unfortunately, the vast amount of agarose in PCLS impedes RNA extraction according to the standard procedures. RESULTS: We established an optimized protocol for RNA isolation from PCLS from humans, rats, mice, marmosets, and rhesus macaques based on the separation of lysis and precipitation steps and a magnetic-bead cleanup procedure. The resulting RNA is of high purity and possesses a high degree of integrity. There are no contaminations affecting RTqPCR efficiency or any enzymatic step in sample preparation for microarray analysis. CONCLUSIONS: In summary, we isolated RNA from PCLS from different species that is well suited for RTqPCR and for microarray analysis as downstream applications.


Assuntos
Pulmão/química , Microtomia/métodos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , RNA/isolamento & purificação , Transcriptoma , Idoso , Animais , Callithrix , Feminino , Humanos , Pulmão/cirurgia , Macaca mulatta , Imãs , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Análise em Microsséries , Microtomia/instrumentação , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos/estatística & dados numéricos , RNA/genética , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
Lancet Diabetes Endocrinol ; 4(3): 221-232, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26656289

RESUMO

BACKGROUND: The combination of insulin and glucagon-like peptide-1 (GLP-1) receptor agonist therapy improves glycaemic control, induces weight loss, and reduces insulin dose needed in type 2 diabetes. We assessed the efficacy and safety of the GLP-1 receptor agonist liraglutide as an add-on therapy to insulin for overweight adult patients with type 1 diabetes. METHODS: We did a randomised, double-blind, placebo-controlled trial at Steno Diabetes Center (Gentofte, Denmark). Patients aged 18 years or older with type 1 diabetes, insufficient glycaemic control (HbA1c >8% [64 mmol/mol]), and overweight (BMI >25 kg/m(2)) were randomly assigned (1:1) to receive insulin treatment plus either liraglutide or placebo (saline solution) by subcutaneous injection once per day. Randomisation was done in blocks of four. Treatment assignment was masked to investigators and patients. Treatment lasted 24 weeks and liraglutide was started at a dose of 0·6 mg per day, escalated to 1·2 mg per day after 1 week, and then again to 1·8 mg per day after another week. Intervals between dose increments could be extended at the discretion of the investigator. The primary endpoint was change in HbA1c from baseline to week 24. Secondary endpoints were changes in hypoglycaemic events, glycaemic variability, glycaemic excursions, insulin dose, bodyweight, postprandial plasma concentrations of glucagon and GLP-1, gastric emptying, blood pressure, heart rate, patient-reported outcome measures, time spent in hypoglycaemia, near-normoglycaemia, and hyperglycaemia, plasma fasting glucose, mean glucose, and cholesterol. Efficacy analyses were calculated by use of a mixed model, whereby a patient's data are used as long as the patient is in the study. The safety analyses were done in the intention-to-treat population, which consisted of all patients who received at least one dose of their randomly assigned study drug. This study is registered with ClinicalTrials.gov, number NCT01612468. FINDINGS: Between July 10, 2012, and May 30, 2014, we enrolled 100 patients with type 1 diabetes, with 50 patients allocated liraglutide and 50 to placebo. Four patients from the liraglutide group and six patients from the placebo group discontinued treatment before 24 weeks. At the end of treatment, change in HbA1c from baseline did not differ between groups (-0·5%, 95% CI -0·8 to -0·4 [-6·0 mmol/mol, 95% CI -8·7 to -4·4] with liraglutide vs -0·3%, -0·6 to -0·2 [-4·0 mmol/mol, -6·6 to -2·3] with placebo; between-group difference -0·2% [-0·5 to 0·1; 2·2 mmol/mol, -5·5 to 1·1], p=0·1833). The number of hypoglycaemic events was reduced with liraglutide, with an incident rate ratio of 0·82 (95% CI 0·74 to 0·90). However, we detected no changes in glycaemic variability (continuous overall net glycaemic action per 60 min from 10·3 [95% CI 9·8 to 10·8] to 9·9 [9·2 to 10·6] in the liraglutide treated patients vs 10·2 [9·7 to 10·7] to 9·7 [9·1 to 10·3] in the placebo treated patients). Both bolus insulin (difference -5·8 IU, 95% CI -10·7 to -0·8, p=0·0227) and bodyweight (difference -6·8 kg, 95% CI -12·2 to -1·4, p=0·0145) decreased with liraglutide treatment compared with placebo. Heart rate increased with liraglutide, with a difference between groups of 7·5 bpm (95% CI 2·8-12·2, p=0·0019). Postprandial plasma glucagon and GLP-1 concentrations did not differ between groups (difference between groups at end of treatment: -408 mmol/L per 240 min [95% CI -941 to 125, p=0·1309] for glucagon and -266 mmol/L per 240 min [-1034 to 501, p=0·4899] for GLP-1). Gastric emptying was delayed after 3 weeks of treatment with liraglutide (19·9 min, 95% CI 0·8 to 39·0, p=0·0412), but we detected no difference after 24 weeks of treatment (-1·5 min, -20·5 to 17·6, p=0·8793). Patient-reported outcome measures differed between groups only with respect to perceived frequency of hypoglycaemia, which was higher with placebo, with a difference between groups of -0·6 (95% CI -1·1 to -0·07, p=0·0257). Liraglutide was associated with more frequent nausea (29 [58%] patients with liraglutide vs five [10%] with placebo), dyspepsia (11 [22%] patients with liraglutide vs one [2%] with placebo), diarrhoea (ten [20%] patients with liraglutide vs one [2%] with placebo), decreased appetite (seven patients [14%] with liraglutide vs none with placebo), and vomiting (seven [14%] patients with liraglutide vs one [2%] with placebo). INTERPRETATION: In patients with type 1 diabetes, overweight, and insufficient glycaemic control, the reduction in HbA1c did not differ between insulin plus placebo and insulin plus liraglutide treatment. Liraglutide was associated with reductions in hypoglycaemic events, bolus and total insulin dose, and bodyweight, and increased heart rate. FUNDING: Novo Nordisk.


Assuntos
Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/tratamento farmacológico , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Liraglutida/uso terapêutico , Sobrepeso/complicações , Pressão Sanguínea/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Hipoglicemiantes/efeitos adversos , Liraglutida/efeitos adversos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
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