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1.
Arch Toxicol ; 98(2): 425-469, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38147116

RESUMO

Fungi of the genus Alternaria are ubiquitous plant pathogens and saprophytes which are able to grow under varying temperature and moisture conditions as well as on a large range of substrates. A spectrum of structurally diverse secondary metabolites with toxic potential has been identified, but occurrence and relative proportion of the different metabolites in complex mixtures depend on strain, substrate, and growth conditions. This review compiles the available knowledge on hazard identification and characterization of Alternaria toxins. Alternariol (AOH), its monomethylether AME and the perylene quinones altertoxin I (ATX-I), ATX-II, ATX-III, alterperylenol (ALP), and stemphyltoxin III (STTX-III) showed in vitro genotoxic and mutagenic properties. Of all identified Alternaria toxins, the epoxide-bearing analogs ATX-II, ATX-III, and STTX-III show the highest cytotoxic, genotoxic, and mutagenic potential in vitro. Under hormone-sensitive conditions, AOH and AME act as moderate xenoestrogens, but in silico modeling predicts further Alternaria toxins as potential estrogenic factors. Recent studies indicate also an immunosuppressive role of AOH and ATX-II; however, no data are available for the majority of Alternaria toxins. Overall, hazard characterization of Alternaria toxins focused, so far, primarily on the commercially available dibenzo-α-pyrones AOH and AME and tenuazonic acid (TeA). Limited data sets are available for altersetin (ALS), altenuene (ALT), and tentoxin (TEN). The occurrence and toxicological relevance of perylene quinone-based Alternaria toxins still remain to be fully elucidated. We identified data gaps on hazard identification and characterization crucial to improve risk assessment of Alternaria mycotoxins for consumers and occupationally exposed workers.


Assuntos
Micotoxinas , Perileno , Humanos , Alternaria/metabolismo , Micotoxinas/toxicidade , Micotoxinas/análise , Mutagênicos/toxicidade , Mutagênicos/metabolismo , Lactonas/toxicidade , Lactonas/metabolismo , Medição de Risco , Contaminação de Alimentos/análise
2.
Int J Mol Sci ; 25(3)2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38339184

RESUMO

The skin is the primary tissue affected by wounds and aging, significantly impacting its protective function. Natural products are widely used in cosmetics, representing a new approach to preventing age-related damage. Nanomedicine combines nanotechnology and traditional treatments to create innovative drugs. The main targets of nanotechnological approaches are wound healing, regeneration, and rejuvenation of skin tissue. The skin barrier is not easily permeable, and the creation of modern nanodevices is a way to improve the passive penetration of substances. In this study, Helichrysum italicum oil (HO) was combined with different types of electrospun nanofibers to study their protective activity on the skin and to evaluate their future application for topical treatments. In the present research, we used biodegradable polymers, including polyvinyl alcohol (PVA) and polyvinylpyrrolidone (PVP), which were characterized by a scanning electron microscope (SEM). All results show a positive trend in cell proliferation and viability of human skin stem cells (SSCs) and BJ fibroblasts pre-treated with combined nanofibers and then exposed to UV stress. Gene expression analysis revealed the activation of a molecular rejuvenation program in SSCs treated with functionalized nanofibers before UV exposure. Understanding the mechanisms involved in skin changes during aging allows for the future application of nanomaterials combined with HO directly to the patients.


Assuntos
Produtos Biológicos , Nanofibras , Envelhecimento da Pele , Humanos , Produtos Biológicos/farmacologia , Pele , Cicatrização , Álcool de Polivinil
3.
Small ; 19(23): e2207207, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36922728

RESUMO

In this study, a 96-well exposure system for safety assessment of nanomaterials is developed and characterized using an air-liquid interface lung epithelial model. This system is designed for sequential nebulization. Distribution studies verify the reproducible distribution over all 96 wells, with lower insert-to-insert variability compared to non-sequential application. With a first set of chemicals (TritonX), drugs (Bortezomib), and nanomaterials (silver nanoparticles and (non-)fluorescent crystalline nanocellulose), sequential exposure studies are performed with human lung epithelial cells followed by quantification of the deposited mass and of cell viability. The developed exposure system offers for the first time the possibility of exposing an air-liquid interface model in a 96-well format, resulting in high-throughput rates, combined with the feature for sequential dosing. This exposure system allows the possibility of creating dose-response curves resulting in the generation of more reliable cell-based assay data for many types of applications, such as safety analysis. In addition to chemicals and drugs, nanomaterials with spherical shapes, but also morphologically more complex nanostructures can be exposed sequentially with high efficiency. This allows new perspectives on in vivo-like and animal-free approaches for chemical and pharmaceutical safety assessment, in line with the 3R principle of replacing and reducing animal experiments.


Assuntos
Nanopartículas Metálicas , Humanos , Prata , Pulmão , Células Epiteliais , Bortezomib
4.
Small ; 17(15): e2006012, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33458959

RESUMO

Microfluidic technology is a valuable tool for realizing more in vitro models capturing cellular and organ level responses for rapid and animal-free risk assessment of new chemicals and drugs. Microfluidic cell-based devices allow high-throughput screening and flexible automation while lowering costs and reagent consumption due to their miniaturization. There is a growing need for faster and animal-free approaches for drug development and safety assessment of chemicals (Registration, Evaluation, Authorisation and Restriction of Chemical Substances, REACH). The work presented describes a microfluidic platform for in vivo-like in vitro cell cultivation. It is equipped with a wafer-based silicon chip including integrated electrodes and a microcavity. A proof-of-concept using different relevant cell models shows its suitability for label-free assessment of cytotoxic effects. A miniaturized microscope within each module monitors cell morphology and proliferation. Electrodes integrated in the microfluidic channels allow the noninvasive monitoring of barrier integrity followed by a label-free assessment of cytotoxic effects. Each microfluidic cell cultivation module can be operated individually or be interconnected in a flexible way. The interconnection of the different modules aims at simulation of the whole-body exposure and response and can contribute to the replacement of animal testing in risk assessment studies in compliance with the 3Rs to replace, reduce, and refine animal experiments.


Assuntos
Técnicas Analíticas Microfluídicas , Preparações Farmacêuticas , Animais , Avaliação Pré-Clínica de Medicamentos , Ensaios de Triagem em Larga Escala , Dispositivos Lab-On-A-Chip , Microfluídica
5.
Respir Res ; 21(1): 222, 2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-32847538

RESUMO

Cystic fibrosis (CF) and chronic obstructive pulmonary disease (COPD) are associated with acute and chronic bacterial infections of the lung. Excessive differentiation of basal cells to mucus-producing goblet cells can result in mucus hyperproduction and loss of mucociliary clearance in the airways of CF and COPD patients. Here, we aimed to investigate the effect of pathogen-associated molecular patterns (PAMPs) on the differentiation of human 3D bronchospheres. Primary human bronchial epithelial cells (HBECs) were differentiated to bronchospheres in the presence of bacterial flagellin and LPS and the synthetic Toll-like receptor (TLR) ligands Pam3CSK4 (TLR-2) and polyinosinic:polycytidylic acid (pIC, TLR-3). Electron and fluorescence microscopy showed that the differentiation of bronchospheres associated with the formation of lumina and appearance of cilia within 30 days after seeding. Incubation with flagellin resulted in a decreased formation of lumina and loss of cilia formation. Incubation with Pam3CSK, pIC, and LPS did not significantly affect formation of lumina and ciliation. Mucus production was strongly increased in response to flagellin and, to a lesser degree, in response to Pam3CSK4. Our results indicate that bacterial factors, such as flagellin, drive the differentiation of the respiratory epithelium towards mucus hyperproduction.


Assuntos
Brônquios/metabolismo , Flagelina/metabolismo , Depuração Mucociliar/fisiologia , Muco/metabolismo , Organoides/metabolismo , Mucosa Respiratória/metabolismo , Brônquios/microbiologia , Células Cultivadas , Flagelina/administração & dosagem , Humanos , Muco/microbiologia , Organoides/microbiologia , Organoides/ultraestrutura , Mucosa Respiratória/microbiologia , Mucosa Respiratória/ultraestrutura
6.
Altern Lab Anim ; 47(3-4): 116-127, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31698922

RESUMO

Serum supplementation is crucial in in vitro cell culture to provide all the essential nutrients needed for cellular processes. Fetal bovine serum (FBS) is considered the 'gold standard', but its production raises serious ethical concerns. Human-derived alternatives to FBS exist in the form of human platelet lysates (hPLs) or human AB serum (ABS). However, these serum products are usually pooled from several donors, in order to have a standardised product without patient-specific deviations. Nevertheless, the use of patient-specific serum in cell culture might be the key to successful transplantation of the cultured cells in medical applications, particularly as it avoids the transmission of infectious components or xenogenic proteins. In addition, the production of non-pooled hPL from single donors is likely to be a cost-effective and time-saving method. The current study used hPL units isolated from single donors and tested their performance as medium supplements for cell culture in comparison with FBS or ABS. This proof-of-concept study aimed to assess the potential of non-pooled hPL for personalised serum supplementation, and thus optimise in vitro models by making them more relevant to human physiology. We showed that A549, HepG2 and Caco-2 human cell lines were generally able to adapt to the new culture conditions and maintain viability, morphology and certain cell-specific characteristics. These results indicate that non-pooled, single patient-derived hPL could be a suitable alternative for in vitro serum supplementation.


Assuntos
Técnicas de Cultura de Células , Soro , Células A549 , Células CACO-2 , Técnicas de Cultura de Células/métodos , Técnicas de Cultura de Células/normas , Proliferação de Células , Células Hep G2 , Humanos
7.
Biomed Pharmacother ; 165: 115179, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37481927

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is among the deadliest cancers worldwide, primarily due to its robust desmoplastic stroma and immunosuppressive tumor microenvironment (TME), which facilitate tumor progression and metastasis. In addition, fibrous tissue leads to sparse vasculature, high interstitial fluid pressure, and hypoxia, thereby hindering effective systemic drug delivery and immune cell infiltration. Thus, remodeling the TME to enhance tumor perfusion, increase drug retention, and reverse immunosuppression has become a key therapeutic strategy. In recent years, targeting epigenetic pathways has emerged as a promising approach to overcome tumor immunosuppression and cancer progression. Moreover, the progress in nanotechnology has provided new opportunities for enhancing the efficacy of conventional and epigenetic drugs. Nano-based drug delivery systems (NDDSs) offer several advantages, including improved drug pharmacokinetics, enhanced tumor penetration, and reduced systemic toxicity. Smart NDDSs enable precise targeting of stromal components and augment the effectiveness of immunotherapy through multiple drug delivery options. This review offers an overview of the latest nano-based approaches developed to achieve superior therapeutic efficacy and overcome drug resistance. We specifically focus on the TME and epigenetic-targeted therapies in the context of PDAC, discussing the advantages and limitations of current strategies while highlighting promising new developments. By emphasizing the immense potential of NDDSs in improving therapeutic outcomes in PDAC, our review paves the way for future research in this rapidly evolving field.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Nanomedicina , Sistemas de Liberação de Fármacos por Nanopartículas , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Microambiente Tumoral/genética , Neoplasias Pancreáticas
8.
Bioelectrochemistry ; 153: 108467, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37244203

RESUMO

This study compares the performance and output of an electrochemical phospholipid membrane platform against respective in vitro cell-based toxicity testing methods using three toxicants of different biological action (chlorpromazine (CPZ), colchicine (COL) and methyl methanesulphonate (MMS)). Human cell lines from seven different tissues (lung, liver, kidney, placenta, intestine, immune system) were used to validate this physicochemical testing system. For the cell-based systems, the effective concentration at 50 % cell death (EC50) values are calculated. For the membrane sensor, a limit of detection (LoD) value was extracted as a quantitative parameter describing the minimum concentration of toxicant which significantly affects the structure of the phospholipid sensor membrane layer. LoD values were found to align well with the EC50 values when acute cell viability was used as an end-point and showed a similar toxicity ranking of the tested toxicants. Using the colony forming efficiency (CFE) or DNA damage as end-point, a different order of toxicity ranking was observed. The results of this study showed that the electrochemical membrane sensor generates a parameter relating to biomembrane damage, which is the predominant factor in decreasing cell viability when in vitro models are acutely exposed to toxicants. These results lead the way to using electrochemical membrane-based sensors for rapid relevant preliminary toxicity screens.


Assuntos
Fígado , Testes de Toxicidade , Humanos , Linhagem Celular , Testes de Toxicidade/métodos , Clorpromazina , Substâncias Perigosas , Fosfolipídeos
9.
Pharm Res ; 29(4): 983-93, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22160813

RESUMO

PURPOSE: A real time detection of gastric cancer-associated biomarker molecules in the lumen of the stomach could assist in early detection of this multi-step malignancy. METHODS: Employing α1-antitrypsin precursor (A1AT) as a secreted biomarker model, a platform with immunoassay capabilities, comprising sensing and detecting compartments was developed. It was made of a microarray-type functionalized glass, containing a high density of amine groups. Trypsin, the capturing moiety, was immobilized to the glass surface with the aid of a PEG-based spacer mixture, identified as being crucial for both capturing and detecting properties. The detecting compartment contained near infrared fluorescently labeled nanoparticles conjugated to A1AT-specific antibodies, aimed at generating an optical signal, detectable by a conventional endoscope or a video capsule. RESULTS: The specific recognition reaction between the captured A1AT and the immuno-nanoparticles generated a profound fluorescence with a signal to noise ratio (SNR) of 12-32, in a biomarker-concentration dependent manner. Moreover, the optical recognition signal was intense enough to be detected by a video capsule simulator (with optical detection capabilities of a video capsule) with a SNR of 6-20. CONCLUSIONS: This platform could serve as a real time diagnostic kit for early detection of a secreted biomarker of gastric cancer.


Assuntos
Biomarcadores Tumorais/análise , Nanopartículas/química , Neoplasias Gástricas/diagnóstico , alfa 1-Antitripsina/análise , Animais , Células CACO-2 , Fluorescência , Vidro/química , Humanos , Imunoensaio/métodos , Camundongos , Polietilenoglicóis/química , Razão Sinal-Ruído , Neoplasias Gástricas/metabolismo , Tripsina/química , Células Tumorais Cultivadas
10.
J Mater Sci Mater Med ; 23(10): 2399-412, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22588504

RESUMO

The use of an "over 1000-nm near-infrared (NIR) in vivo fluorescence bioimaging" system based on lanthanide containing inorganic nanostructures emitting in the visible and NIR range under 980-nm excitation is proposed. It may overcome problems of currently used biomarkers including color fading, phototoxicity and scattering. Gd(2)O(3):Er(3+),Yb(3+) nanoparticles and nanorods showing upconversion and NIR emission are synthesized and their cytotoxic behavior is investigated by incubation with B-cell hybridomas and macrophages. Surface modification with PEG-b-PAAc provides the necessary chemical durability reducing the release of toxic Gd(3+) ions. NIR fluorescence microscopy is used to investigate the suitability of the nanostructures as NIR-NIR biomarkers. The in vitro uptake of bare and modified nanostructures by macrophages is investigated by confocal laser scanning microscopy. In vivo investigations revealed nanostructures in liver, lung, kidneys and spleen a few hours after injection into mice, while most of the nanostructures have been removed from the body after 24 h.


Assuntos
Érbio/química , Gadolínio/química , Nanoestruturas , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Itérbio/química , Animais , Materiais Biocompatíveis , Linhagem Celular , Sobrevivência Celular , Érbio/farmacocinética , Gadolínio/farmacocinética , Técnicas In Vitro , Camundongos , Microscopia Eletrônica de Varredura , Difração de Pó , Propriedades de Superfície , Distribuição Tecidual , Itérbio/farmacocinética
11.
Adv Biol (Weinh) ; 6(2): e2101139, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34962104

RESUMO

The substantial socioeconomic burden of lung diseases, recently highlighted by the disastrous impact of the coronavirus disease 2019 (COVID-19) pandemic, accentuates the need for interventive treatments capable of decelerating disease progression, limiting organ damage, and contributing to a functional tissue recovery. However, this is hampered by the lack of accurate human lung research models, which currently fail to reproduce the human pulmonary architecture and biochemical environment. Induced pluripotent stem cells (iPSCs) and organ-on-chip (OOC) technologies possess suitable characteristics for the generation of physiologically relevant in vitro lung models, allowing for developmental studies, disease modeling, and toxicological screening. Importantly, these platforms represent potential alternatives for animal testing, according to the 3Rs (replace, reduce, refine) principle, and hold promise for the identification and approval of new chemicals under the European REACH (registration, evaluation, authorization and restriction of chemicals) framework. As such, this review aims to summarize recent progress made in human iPSC- and OOC-based in vitro lung models. A general overview of the present applications of in vitro lung models is presented, followed by a summary of currently used protocols to generate different lung cell types from iPSCs. Lastly, recently developed iPSC-based lung models are discussed.


Assuntos
COVID-19 , Células-Tronco Pluripotentes Induzidas , Preparações Farmacêuticas , Animais , Humanos , Pulmão , SARS-CoV-2
12.
Pharmaceuticals (Basel) ; 15(2)2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35215362

RESUMO

Static in vitro permeation experiments are commonly used to gain insights into the permeation properties of drug substances but exhibit limitations due to missing physiologic cell stimuli. Thus, fluidic systems integrating stimuli, such as physicochemical fluxes, have been developed. However, as fluidic in vitro studies display higher complexity compared to static systems, analysis of experimental readouts is challenging. Here, the integration of in silico tools holds the potential to evaluate fluidic experiments and to investigate specific simulation scenarios. This study aimed to develop in silico models that describe and predict the permeation and disposition of two model substances in a static and fluidic in vitro system. For this, in vitro permeation studies with a 16HBE cellular barrier under both static and fluidic conditions were performed over 72 h. In silico models were implemented and employed to describe and predict concentration-time profiles of caffeine and diclofenac in various experimental setups. For both substances, in silico modeling identified reduced apparent permeabilities in the fluidic compared to the static cellular setting. The developed in vitro-in silico modeling framework can be expanded further, integrating additional cell tissues in the fluidic system, and can be employed in future studies to model pharmacokinetic and pharmacodynamic drug behavior.

13.
Nanomaterials (Basel) ; 12(3)2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35159859

RESUMO

Data suitable for assembling a physiologically-based pharmacokinetic (PBPK) model for nanoparticles (NPs) remain relatively scarce. Therefore, there is a trend in extrapolating the results of in vitro and in silico studies to in vivo nanoparticle hazard and risk assessment. To evaluate the reliability of such approach, a pharmacokinetic study was performed using the same polyethylene glycol-coated gold nanoparticles (PEG-AuNPs) in vitro and in vivo. As in vitro models, human cell lines TH1, A549, Hep G2, and 16HBE were employed. The in vivo PEG-AuNP biodistribution was assessed in rats. The internalization and exclusion of PEG-AuNPs in vitro were modeled as first-order rate processes with the partition coefficient describing the equilibrium distribution. The pharmacokinetic parameters were obtained by fitting the model to the in vitro data and subsequently used for PBPK simulation in vivo. Notable differences were observed in the internalized amount of Au in individual cell lines compared to the corresponding tissues in vivo, with the highest found for renal TH1 cells and kidneys. The main reason for these discrepancies is the absence of natural barriers in the in vitro conditions. Therefore, caution should be exercised when extrapolating in vitro data to predict the in vivo NP burden and response to exposure.

14.
Crit Rev Oncol Hematol ; 180: 103865, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36334880

RESUMO

Pancreatic neuroendocrine neoplasms (pNENs) are rare cancers with broad challenges for their management. The main clinical obstacles are the high rate of patients diagnosed at advanced stages, lack of prognostic markers for early detection of disease recurrence in resected patients, significant limitations in identifying those who will benefit from adjuvant therapy, and timely recognition of treatment response. Therefore, the discovery of new prognostic and predictive markers is necessary for patient stratification and clinical management. Liquid biopsy, which has revolutionized the field of clinical oncology, is extremely under-investigated in pNENs. This review highlights its potential and the recent advances in related technologies, as candidates for the delivery of the new tools that can help to refine pNEN diagnosis and to personalize treatment. In addition, the opportunities and limitations of available preclinical research models with regard to biomarker research are discussed in light of pNEN clinical needs.


Assuntos
Tumores Neuroendócrinos , Neoplasias Pancreáticas , Humanos , Tumores Neuroendócrinos/diagnóstico , Tumores Neuroendócrinos/terapia , Tumores Neuroendócrinos/patologia , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/terapia , Neoplasias Pancreáticas/patologia , Recidiva Local de Neoplasia , Biópsia Líquida , Prognóstico
15.
Part Fibre Toxicol ; 8(1): 8, 2011 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-21306632

RESUMO

BACKGROUND: With the increasing use of nanomaterials, the need for methods and assays to examine their immunosafety is becoming urgent, in particular for nanomaterials that are deliberately administered to human subjects (as in the case of nanomedicines). To obtain reliable results, standardised in vitro immunotoxicological tests should be used to determine the effects of engineered nanoparticles on human immune responses. However, before assays can be standardised, it is important that suitable methods are established and validated. RESULTS: In a collaborative work between European laboratories, existing immunological and toxicological in vitro assays were tested and compared for their suitability to test effects of nanoparticles on immune responses. The prototypical nanoparticles used were metal (oxide) particles, either custom-generated by wet synthesis or commercially available as powders. Several problems and challenges were encountered during assay validation, ranging from particle agglomeration in biological media and optical interference with assay systems, to chemical immunotoxicity of solvents and contamination with endotoxin. CONCLUSION: The problems that were encountered in the immunological assay systems used in this study, such as chemical or endotoxin contamination and optical interference caused by the dense material, significantly affected the data obtained. These problems have to be solved to enable the development of reliable assays for the assessment of nano-immunosafety.


Assuntos
Bioensaio/métodos , Bioensaio/normas , Células/imunologia , Fatores Imunológicos/imunologia , Nanopartículas Metálicas , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Células/citologia , Células Cultivadas , Humanos , Interleucina-8/genética , Interleucina-8/imunologia , Nanopartículas Metálicas/efeitos adversos , Nanopartículas Metálicas/química , Regiões Promotoras Genéticas , Reprodutibilidade dos Testes , Solventes
16.
Nanomedicine ; 7(2): 228-37, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20732457

RESUMO

Nanoparticulate contrast agents for molecular imaging have attracted widespread interest for diagnostic applications with high resolution in medicine. Here we introduce polymer-based multifunctional nanoparticles exhibiting a near-infrared absorption in the range of the Nd:YAG laser wavelength of 1064 nm as a novel resorbable photoacoustic (PA) contrast system and report about their biological evaluation. Submicron-sized spherical nanoparticles with a high encapsulation efficiency (>87%) were created by incorporation of near-infrared dyes (IR5/IR26) in poly[(rac-lactide)-co-glycolide] (PLGA) with 50 mol% glycolide content via a specific spray-drying process in good yield (>75%). Subsequent application of a centrifugation protocol produced two different size fractions with diameters in the ranges 445-540 nm and 253-305 nm; these were further used for investigation of PA properties and cytotoxic effects. The prepared PLGA nanoparticles exhibited PA properties using a Nd:YAG laser-based system. After exposure of particle concentrations up to 10 µg·ml(-1) for 2 days no effects on viability, mitochondrial activity and proliferation, and cell death of human hepatocarcinoma cells and monkey kidney cells were observed. The excellent PA properties in combination with the positive biological results qualify the dye-loaded PLGA particles as promising candidates for a resorbable PA contrast system. FROM THE CLINICAL EDITOR: Photoacoustics (PA), a new modality, in which laser light is shined into tissue and absorbed by inherent proteins or synthetic particles is reflected back and received as ultrasound. This technique was shown to be effective with an erodible polymer particle containing near infrared dyes. In vitro, the PA properties of the PLGA particles persisted for 2 days in cell culture.


Assuntos
Meios de Contraste/administração & dosagem , Portadores de Fármacos/química , Ácido Láctico/química , Nanopartículas/química , Ácido Poliglicólico/química , Acústica , Animais , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Células Hep G2 , Humanos , Ácido Láctico/efeitos adversos , Lasers de Estado Sólido , Microscopia Eletrônica de Varredura , Nanopartículas/efeitos adversos , Nanopartículas/ultraestrutura , Tamanho da Partícula , Ácido Poliglicólico/efeitos adversos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Espectroscopia de Luz Próxima ao Infravermelho , Ultrassonografia , Células Vero
17.
Nanomaterials (Basel) ; 11(11)2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34835900

RESUMO

Determination of acute toxicity to vertebrates in aquatic environments is mainly performed following OECD test guideline 203, requiring the use of a large number of fish and with mortality as endpoint. This test is also used to determine toxicity of nanomaterials in aquatic environments. Since a replacement method for animal testing in nanotoxicity studies is desirable, the feasibility of fish primary cultures or cell lines as a model for nanotoxicity screenings is investigated here. Dicentrarchus labrax primary cultures and RTgill-W1 cell line were exposed to several concentrations (0.1 to 200 ug/mL) of different nanoparticles (TiO2, polystyrene and silver), and cytotoxicity, metabolic activity and reactive oxygen species formation were investigated after 24 and 48 h of exposure. Protein corona as amount of protein bound, as well as the influence of surface modification (-COOH, -NH2), exposure media (Leibovitz's L15 or seawater), weathering and cell type were the experimental variables included to test their influence on the results of the assays. Data from all scenarios was split based on the significance each experimental variable had in the result of the cytotoxicity tests, in an exploratory approach that allows for better understanding of the determining factors affecting toxicity. Data shows that more variables significantly influenced the outcome of toxicity tests when the primary cultures were exposed to the different nanoparticles. Toxicity tests performed in RTgill-W1 were influenced only by exposure time and nanoparticle concentration. The whole data set was integrated in a biological response index to show the overall impact of nanoparticle exposures.

18.
Nanomaterials (Basel) ; 11(6)2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34063963

RESUMO

A better understanding of their interaction with cell-based tissue is a fundamental prerequisite towards the safe production and application of engineered nanomaterials. Quantitative experimental data on the correlation between physicochemical characteristics and the interaction and transport of engineered nanomaterials across biological barriers, in particular, is still scarce, thus hampering the development of effective predictive non-testing strategies. Against this background, the presented study investigated the translocation of gold and silver nanoparticles across the gastrointestinal barrier along with related biological effects using an in vitro 3D-triple co-culture cell model. Standardized in vitro assays and quantitative polymerase chain reaction showed no significant influence of the applied nanoparticles on both cell viability and generation of reactive oxygen species. Transmission electron microscopy indicated an intact cell barrier during the translocation study. Single particle ICP-MS revealed a time-dependent increase of translocated nanoparticles independent of their size, shape, surface charge, and stability in cell culture medium. This quantitative data provided the experimental basis for the successful mathematical description of the nanoparticle transport kinetics using a non-linear mixed effects modeling approach. The results of this study may serve as a basis for the development of predictive tools for improved risk assessment of engineered nanomaterials in the future.

19.
ACS Appl Bio Mater ; 4(3): 2558-2569, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35014373

RESUMO

One of the major environmental problems is a global metal contamination. Heavy metals are nonbiodegradable and tend to accumulate in living organisms. Therefore, searching for biocompatible materials with enhanced sorption capabilities for selective removal of toxic elements from complex environments, low cost, ease of operation, and large available quantities that meet all requirements of the Green Chemistry concept is a current engineering and analytical task. We present a comprehensive study toward construction of an advanced biomembrane-based technology for recovery of several heavy metals and ruthenium by microdimensional alginate scaffolds. The chosen design of alginate scaffolds and their operational conditions were monitored during removal of Cd(II), Co(II), Pb(II), As(III), and Ru(III) in modeled aqueous solutions, cell culture medium, and in the presence of A549 lung cells by a tandem of biological (live/dead cell test), physical nanoanalytical (TEM/EDX, SEM/EDX), and chemical (FT-IR, HR-ICP-MS) assays. More precisely, the impact of certain experimental conditions, viz., medium acidity and matrix effects on sorption capacity of the above-mentioned elements, was investigated in detail. Remarkably, a different attachment behavior during adsorption of chosen elements by alginate scaffolds was observed. In addition, we revealed an essential concentration dependent effect of loaded heavy metals and ruthenium on cultivated cells. The obtained data allow us to gain a deeper insight into the interactions occurring in the studied biomaterial-inorganic system. Moreover, the obtained dependencies can be widely used for the development of alginate-based membrane technology employed for the protection of environmental and biological samples from the toxic pollutants.


Assuntos
Alginatos/farmacologia , Materiais Biocompatíveis/farmacologia , Metais Pesados/farmacologia , Células A549 , Adsorção , Alginatos/química , Materiais Biocompatíveis/química , Sobrevivência Celular/efeitos dos fármacos , Humanos , Teste de Materiais , Metais Pesados/química , Tamanho da Partícula , Células Tumorais Cultivadas
20.
Lab Chip ; 21(21): 4237-4248, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34605521

RESUMO

Translation of advanced cell-based assays exhibiting a higher degree of automation, miniaturization, and integration of complementary sensing functions is mainly limited by the development of industrial-relevant prototypes that can be readily produced in larger volumes. Despite the increasing number of academic publications in recent years, the manufacturability of these microfluidic cell cultures systems is largely ignored, thus severely restricting their implementation in routine toxicological applications. We have developed a dual-sensor integrated microfluidic cell analysis platform using industrial specifications, materials, and fabrication methods to conduct risk assessment studies of engineered nanoparticles to overcome this academic-industrial gap. Non-invasive and time-resolved monitoring of cellular oxygen uptake and metabolic activity (pH) in the absence and presence of nanoparticle exposure is accomplished by integrating optical sensor spots into a cyclic olefin copolymer (COC)-based microfluidic platform. Results of our nanotoxicological study, including two physiological cell barriers that are essential in the protection from exogenous factors, the intestine (Caco-2) and the vasculature (HUVECs) showed that the assessment of the cells' total energy metabolism is ideally suited to rapidly detect cytotoxicities. Additional viability assay verification using state-of-the-art dye exclusion assays for nanotoxicology demonstrated the similarity and comparability of our results, thus highlighting the benefits of employing a compact and cost-efficient microfluidic dual-sensor platform as a pre-screening tool in nanomaterial risk assessment and as a rapid quality control measure in medium to high-throughput settings.


Assuntos
Dispositivos Lab-On-A-Chip , Técnicas Analíticas Microfluídicas , Células CACO-2 , Humanos , Concentração de Íons de Hidrogênio , Oxigênio
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