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1.
Dis Model Mech ; 13(9)2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32887790

RESUMO

The spread of the novel virus SARS coronavirus 2 (SARS-CoV-2) was explosive, with cases first identified in December 2019, and >22 million people infected and >775,000 deaths as of August 2020. SARS-CoV-2 can cause severe respiratory disease in humans leading to coronavirus disease 2019 (COVID-19). The development of effective clinical interventions, such as antivirals and vaccines that can limit or even prevent the burden and spread of SARS-CoV-2, is a global health priority. Testing of leading antivirals, monoclonal antibody therapies and vaccines against SARS-CoV-2 will require robust animal and cell models of viral pathogenesis. In this Special Article, we discuss the cell-based and animal models of SARS-CoV-2 infection and pathogenesis that have been described as of August 2020. We also outline the outstanding questions for which researchers can leverage animal and cell-based models to improve our understanding of SARS-CoV-2 pathogenesis and protective immunity. Taken together, the refinement of models of SARS-CoV-2 infection will be critical to guide the development of therapeutics and vaccines against SARS-CoV-2 to end the COVID-19 pandemic.


Assuntos
Betacoronavirus/imunologia , Betacoronavirus/patogenicidade , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Animais , Antivirais/uso terapêutico , Betacoronavirus/efeitos dos fármacos , Células Cultivadas , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/prevenção & controle , Modelos Animais de Doenças , Interações entre Hospedeiro e Microrganismos , Humanos , Pandemias , Pneumonia Viral/tratamento farmacológico , Especificidade da Espécie , Técnicas de Cultura de Tecidos , Vacinas Virais/uso terapêutico
2.
J Anim Sci ; 98(8)2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32745186

RESUMO

Cultured meat grown in vitro from animal cells has the potential to address many of the ethical, environmental, and public health issues associated with conventional meat production. However, as well as overcoming technical challenges to producing cultured meat, producers and advocates of the technology must consider a range of social issues, including consumer appeal and acceptance, media coverage, religious status, regulation, and potential economic impacts. Whilst much has been written on the prospects for consumer appeal and acceptance of cultured meat, less consideration has been given to the other aspects of the social world that will interact with this new technology. Here, each of these issues is considered in turn, forming a view of cultured meat as a technology with a diverse set of societal considerations and far-reaching social implications. It is argued that the potential gains from a transition to cultured meat are vast, but that cultural phenomena and institutions must be navigated carefully for this nascent industry to meet its potential.


Assuntos
Comportamento do Consumidor , Tecnologia de Alimentos , Carne/provisão & distribução , Animais , Cultura , Preferências Alimentares , Humanos , Técnicas de Cultura de Tecidos
3.
PLoS One ; 15(8): e0235634, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760078

RESUMO

Otitis media, the most common disease of childhood, is characterized by extensive changes in the morphology of the middle ear cavity. This includes hyperplasia of the mucosa that lines the tympanic cavity, from a simple monolayer of squamous epithelium into a greatly thickened, respiratory-type mucosa. The processes that control this response, which is critical to otitis media pathogenesis and recovery, are incompletely understood. Given the central role of protein phosphorylation in most intracellular processes, including cell proliferation and differentiation, we screened a library of kinase inhibitors targeting members of all the major families in the kinome for their ability to influence the growth of middle ear mucosal explants in vitro. Of the 160 inhibitors, 30 were found to inhibit mucosal growth, while two inhibitors enhanced tissue proliferation. The results suggest that the regulation of infection-mediated tissue growth in the ME mucosa involves multiple cellular processes that span the kinome. While some of the pathways and processes identified have been previously implicated in mucosa hyperplasia others are novel. The results were used to generate a global model of growth regulation by kinase pathways. The potential for therapeutic applications of the results are discussed.


Assuntos
Proliferação de Células/efeitos dos fármacos , Otite Média/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Avaliação Pré-Clínica de Medicamentos , Haemophilus influenzae/patogenicidade , Ensaios de Triagem em Larga Escala , Humanos , Hiperplasia/tratamento farmacológico , Hiperplasia/microbiologia , Hiperplasia/patologia , Camundongos , Membrana Mucosa/efeitos dos fármacos , Membrana Mucosa/microbiologia , Membrana Mucosa/patologia , Otite Média/microbiologia , Otite Média/patologia , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Ratos , Técnicas de Cultura de Tecidos
4.
J Anim Sci ; 98(8)2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32745187

RESUMO

Proof-of-principle for large-scale engineering of edible muscle tissue, in vitro, was established with the product's introduction in 2013. Subsequent research and commentary on the potential for cell-based meat to be a viable food option and potential alternative to conventional meat have been significant. While some of this has focused on the biology and engineering required to optimize the manufacturing process, a majority of debate has focused on cultural, environmental, and regulatory considerations. Animal scientists and others with expertise in muscle and cell biology, physiology, and meat science have contributed to the knowledge base that has made cell-based meat possible and will continue to have a role in the future of the new product. Importantly, the successful introduction of cell-based meat that looks and tastes like conventional meat at a comparable price has the potential to displace and/or complement conventional meat in the marketplace.


Assuntos
Comportamento do Consumidor , Tecnologia de Alimentos , Carne/provisão & distribução , Animais , Cultura , Preferências Alimentares , Humanos , Músculo Esquelético/crescimento & desenvolvimento , Células-Tronco , Técnicas de Cultura de Tecidos , Estados Unidos , United States Food and Drug Administration
5.
PLoS Negl Trop Dis ; 14(8): e0008482, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32776923

RESUMO

Current drug therapies for cutaneous leishmaniasis are often difficult to administer and treatment failure is an increasingly common occurrence. The efficacy of anti-leishmanial therapy relies on a combination of anti-parasite activity of drugs and the patient's immune response. Previous studies have reported in vitro antimicrobial activity of histamine 1-receptor antagonists (H1RAs) against different pathogens. We used an ex vivo explant culture of lymph nodes from mice infected with Leishmania major to screen H1RAs compounds. Azelastine (AZ) and Fexofenadine (FX) showed remarkable ex vivo efficacy (EC50 = 0.05 and 1.50 µM respectively) and low in vitro cytotoxicity yielding a high therapeutic index. AZ significantly decreased the expression of H1R and the proinflammatory cytokine IL-1ẞ in the ex vivo system, which were shown to be augmented by histamine addition. The anti-leishmanial efficacy of AZ was enhanced in the presence of T cells from infected mice suggesting an immune-modulatory mechanism of parasite suppression. L. major infected BALB/c mice treated per os with FX or intralesionally with AZ showed a significant reduction of lesion size (FX = 69%; AZ = 52%). Furthermore, there was significant parasite suppression in the lesion (FX = 82%; AZ = 87%) and lymph nodes (FX = 81%; AZ = 36%) with no observable side effects. AZ and FX and potentially other H1RAs are good candidates for assessing efficacy in larger studies as monotherapies or in combination with current anti-leishmanial drugs to treat cutaneous leishmaniasis.


Assuntos
Antagonistas dos Receptores Histamínicos H1 não Sedativos/uso terapêutico , Leishmaniose Cutânea/tratamento farmacológico , Ftalazinas/uso terapêutico , Terfenadina/análogos & derivados , Animais , Leishmania major , Linfonodos/parasitologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Molecular , Ftalazinas/química , Terfenadina/química , Terfenadina/uso terapêutico , Técnicas de Cultura de Tecidos
6.
Methods Mol Biol ; 2203: 77-88, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32833205

RESUMO

Porcine deltacoronavirus (PDCoV) has emerged as a novel, contagious swine enteric coronavirus that causes watery diarrhea and/or vomiting and intestinal villous atrophy in nursing piglets. PDCoV-related diarrhea first occurred in the USA in 2014 and was subsequently reported in South Korea, China, Thailand, Vietnam, and Lao People's Democratic Republic, leading to massive economic losses and posing a threat to the swine industry worldwide. Currently, no treatments or vaccines for PDCoV are available. The critical step in the development of potential vaccines against PDCoV infection is the isolation and propagation of PDCoV in cell culture. This chapter provides a detailed protocol for isolation and propagation of PDCoV in swine testicular (ST) and LLC porcine kidney (LLC-PK) cell cultures supplemented with pancreatin and trypsin, respectively. Filtered clinical samples (swine intestinal contents or feces) applied to ST or LLC-PK cells produce cytopathic effects characterized by rounding, clumping, and detachment of cells. PDCoV replication in cells can be quantifiably monitored by qRT-PCR, immunofluorescence assays, and immune-electron microscopy. Infectious viral titers can be evaluated by using plaque assays or 50% tissue culture infectious dose (TCID50) assays. The ST or LLC-PK cells efficiently supported serial passage and propagation of PDCoV. After serial passage of PDCoV in either ST or LLC-PK cells, the virus can be purified further in ST cells by plaque assays.


Assuntos
Coronavirus/isolamento & purificação , Doenças dos Suínos/virologia , Técnicas de Cultura de Tecidos/métodos , Animais , Células Cultivadas , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/virologia , Fezes/virologia , Inoculações Seriadas , Suínos
7.
Nat Commun ; 11(1): 3265, 2020 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-32601271

RESUMO

The culture of live pancreatic tissue slices is a powerful tool for the interrogation of physiology and pathology in an in vitro setting that retains near-intact cytoarchitecture. However, current culture conditions for human pancreatic slices (HPSs) have only been tested for short-term applications, which are not permissive for the long-term, longitudinal study of pancreatic endocrine regeneration. Using a culture system designed to mimic the physiological oxygenation of the pancreas, we demonstrate high viability and preserved endocrine and exocrine function in HPS for at least 10 days after sectioning. This extended lifespan allowed us to dynamically lineage trace and quantify the formation of insulin-producing cells in HPS from both non-diabetic and type 2 diabetic donors. This technology is expected to be of great impact for the conduct of real-time regeneration/developmental studies in the human pancreas.


Assuntos
Ilhotas Pancreáticas/citologia , Pâncreas/citologia , Técnicas de Cultura de Tecidos/métodos , Animais , Humanos , Estudos Longitudinais , Camundongos , Modelos Biológicos , Regeneração , Células-Tronco/citologia
8.
PLoS One ; 15(7): e0230464, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32645102

RESUMO

The current study focuses on the usage of bio synthesized zinc oxide nanoparticles to increase the tissue culture efficiency of important forage grass Panicum virgatum. Zinc being a micronutrient enhanced the callogenesis and regeneration efficiency of Panicum virgatum at different concentrations. Here, we synthesized zinc oxide nanoparticles through Cymbopogon citratus leaves extract to evaluate the effect of zinc oxide nanoparticles on plant regeneration ability in switchgrass. X-ray diffraction (XRD) and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) validate phase purity of green synthesize Zinc oxide nanoparticles whereas, electron microscopy (SEM) has illustrated the average size of particle 50±4 nm with hexagonal rod like shape. Energy dispersive spectroscopy X-ray (EDS) depicted major peaks of Zn (92.68%) while minor peaks refer to Oxygen (7.32%). ZnO-NPs demonstrated the incredibly promising results against callogenesis. Biosynthesized ZnO-NPs at optimum concentration showed very promising effect on plant regeneration ability. Both the explants, seeds and nodes showed dose dependent response and upon high doses exceeding 40 mg/L the results were recorded negative, whereas at 30 mg/L both explants demonstrated 70% and 76% regeneration frequency. The results conclude that ZnO-NPs enhance the plant growth and development and tailored the nutritive properties at nano-scale. Furthermore, eco-friendly approach of ZnO-NPs synthesis is strongly believed to improve in vitro regeneration frequencies in several other monocot plants.


Assuntos
Nanopartículas Metálicas , Panicum/efeitos dos fármacos , Panicum/crescimento & desenvolvimento , Técnicas de Cultura de Tecidos , Óxido de Zinco/farmacologia , Cymbopogon , Nanopartículas Metálicas/ultraestrutura , Regeneração , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Óxido de Zinco/síntese química
9.
Nat Protoc ; 15(8): 2413-2442, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32690957

RESUMO

Cancer invasion and metastasis are challenging to study in vivo since they occur deep inside the body over extended time periods. Organotypic 3D culture of fresh tumor tissue enables convenient real-time imaging, genetic and microenvironmental manipulation and molecular analysis. Here, we provide detailed protocols to isolate and culture heterogenous organoids from murine and human primary and metastatic site tumors. The time required to isolate organoids can vary based on the tissue and organ type but typically takes <7 h. We describe a suite of assays that model specific aspects of metastasis, including proliferation, survival, invasion, dissemination and colony formation. We also specify comprehensive protocols for downstream applications of organotypic cultures that will allow users to (i) test the role of specific genes in regulating various cellular processes, (ii) distinguish the contributions of several microenvironmental factors and (iii) test the effects of novel therapeutics.


Assuntos
Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Técnicas de Cultura de Tecidos/métodos , Animais , Humanos , Camundongos , Metástase Neoplásica
10.
Med Sci (Paris) ; 36(6-7): 600-606, 2020.
Artigo em Francês | MEDLINE | ID: mdl-32614311

RESUMO

In inherited retinal diseases such retinitis pigmentosa, characterized by progressive loss of light sensitive neurons (photoreceptors), cell therapy is now considered as an attractive strategy. Photoreceptor cell replacement would be valuable for restoring function to retinas in a way that is independent from the cause of the disease. With advances in stem cell biology, considerable strides have been made towards the generation of retinal cells, in particular with the development of 3D culture systems allowing the generation of retinal organoids from pluripotent stem cells. In this review, we present a state-of-the art of preclinical strategies conducted in animal models for photoreceptor replacement from stem cell-derived photoreceptors and we discuss the important obstacles to overcome in the future.


Assuntos
Células Fotorreceptoras/transplante , Retinite Pigmentosa/terapia , Terapias em Estudo/métodos , Terapias em Estudo/tendências , Animais , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/transplante , Organoides/citologia , Organoides/fisiologia , Células Fotorreceptoras/citologia , Células Fotorreceptoras/fisiologia , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/transplante , Retina/citologia , Retina/embriologia , Retina/transplante , Degeneração Retiniana/terapia , Retinite Pigmentosa/patologia , Índice de Gravidade de Doença , Técnicas de Cultura de Tecidos , Coleta de Tecidos e Órgãos/métodos , Coleta de Tecidos e Órgãos/normas , Coleta de Tecidos e Órgãos/tendências
11.
Med Sci (Paris) ; 36(6-7): 626-632, 2020.
Artigo em Francês | MEDLINE | ID: mdl-32614314

RESUMO

Generation of retinal organoids from pluripotent stem cells represents an important advance in the study of retinal development and offer new perspectives for the study of retinal diseases missing suitable animal models. Understanding the key stages of retinal development in vertebrates enabled to design protocols to generate self-organized three-dimensional structures derived from pluripotent stem cells and containing all retinal cell types. In addition to their application in basic research, such as the characterization of molecular and cellular mechanisms in retinal pathophysiology, these miniature organs also open up encouraging prospects in the field of cell therapy or the screening of therapeutic molecules, although some obstacles remain to be overcome.


Assuntos
Organoides/citologia , Retina/citologia , Doenças Retinianas/etiologia , Doenças Retinianas/patologia , Doenças Retinianas/terapia , Animais , Células Cultivadas , Humanos , Modelos Biológicos , Organoides/fisiologia , Retina/patologia , Retina/fisiologia , Terapias em Estudo/métodos , Terapias em Estudo/tendências , Técnicas de Cultura de Tecidos/métodos , Técnicas de Cultura de Tecidos/tendências
12.
Nat Commun ; 11(1): 3111, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32561725

RESUMO

Midbrain dopaminergic (DA) axons make long longitudinal projections towards the striatum. Despite the importance of DA striatal innervation, processes involved in establishment of DA axonal connectivity remain largely unknown. Here we demonstrate a striatal-specific requirement of transcriptional regulator Nolz1 in establishing DA circuitry formation. DA projections are misguided and fail to innervate the striatum in both constitutive and striatal-specific Nolz1 mutant embryos. The lack of striatal Nolz1 expression results in nigral to pallidal lineage conversion of striatal projection neuron subtypes. This lineage switch alters the composition of secreted factors influencing DA axonal tract formation and renders the striatum non-permissive for dopaminergic and other forebrain tracts. Furthermore, transcriptomic analysis of wild-type and Nolz1-/- mutant striatal tissue led to the identification of several secreted factors that underlie the observed guidance defects and proteins that promote DA axonal outgrowth. Together, our data demonstrate the involvement of the striatum in orchestrating dopaminergic circuitry formation.


Assuntos
Orientação de Axônios/fisiologia , Axônios/fisiologia , Corpo Estriado/crescimento & desenvolvimento , Neurônios Dopaminérgicos/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Animais , Carbocianinas/administração & dosagem , Corpo Estriado/diagnóstico por imagem , Embrião de Mamíferos , Feminino , Corantes Fluorescentes/administração & dosagem , Peptídeos e Proteínas de Sinalização Intracelular/genética , Microscopia Intravital , Camundongos Knockout , Técnicas Analíticas Microfluídicas , Microinjeções , Microscopia Confocal , Rede Nervosa/fisiologia , Proteínas do Tecido Nervoso/genética , Técnicas de Cultura de Tecidos
13.
PLoS One ; 15(6): e0233963, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32530961

RESUMO

Eclipta alba L., also known as false daisy, is well known and commercially attractive plant with excellent hepatotoxic and antidiabetic activities. Light is considered a key modulator in plant morphogenesis and survival by regulating important physiological cascades. Current study was carried out to investigate growth and developmental aspects of E. alba under differential effect of multispectral lights. In vitro derived callus culture of E. alba was exposed to multispectral monochromatic lights under controlled aseptic conditions. Maximum dry weight was recorded in culture grown under red light (11.2 g/L) whereas negative effect was observed under exposure of yellow light on callus growth (4.87 g/L). Furthermore, red light significantly enhanced phenolics and flavonoids content (TPC: 57.8 mg/g, TFC: 11.1 mg/g) in callus cultures compared to rest of lights. HPLC analysis further confirmed highest accumulation of four major compounds i.e. coumarin (1.26 mg/g), eclalbatin (5.00 mg/g), wedelolactone (32.54 mg/g) and demethylwedelolactone (23.67 mg/g) and two minor compounds (ß-amyrin: 0.38 mg/g, luteolin: 0.39 mg/g) in red light treated culture whereas stigmasterol was found optimum (0.22 mg/g) under blue light. In vitro based biological activities including antioxidant, antidiabetic and lipase inhibitory assays showed optimum values in cultures exposed to red light, suggesting crucial role of these phytochemicals in the enhancement of the therapeutic potential of E. alba. These results clearly revealed that the use of multispectral lights in in vitro cultures could be an effective strategy for enhanced production of phytochemicals.


Assuntos
Antioxidantes/metabolismo , Eclipta/metabolismo , Eclipta/efeitos da radiação , Hipoglicemiantes/metabolismo , Compostos Fitoquímicos/metabolismo , Antioxidantes/química , Cumarínicos/metabolismo , Eclipta/crescimento & desenvolvimento , Flavonoides/metabolismo , Hipoglicemiantes/química , Luz , Fenóis/metabolismo , Compostos Fitoquímicos/química , Metabolismo Secundário/efeitos da radiação , Técnicas de Cultura de Tecidos
14.
Nat Commun ; 11(1): 2979, 2020 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-32532981

RESUMO

NMDA receptor-dependent long-term depression (NMDAR-LTD) is a long-lasting form of synaptic plasticity. Its expression is mediated by the removal of AMPA receptors from postsynaptic membranes. Under basal conditions, endocytosed AMPA receptors are rapidly recycled back to the plasma membrane. In NMDAR-LTD, however, they are diverted to late endosomes for degradation. The mechanism for this switch is largely unclear. Additionally, the inducibility of NMDAR-LTD is greatly reduced in adulthood. The underlying mechanism and physiological significance of this phenomenon are elusive. Here, we report that autophagy inhibition is essential for the induction and developmental dampening of NMDAR-LTD. Autophagy is inhibited during NMDAR-LTD to decrease endocytic recycling. Autophagy inhibition is both necessary and sufficient for LTD induction. In adulthood, autophagy is up-regulated to make LTD induction harder, thereby preventing the adverse effect of excessive LTD on memory consolidation. These findings reveal the unrecognized functions of autophagy in synaptic plasticity, endocytic recycling, and memory.


Assuntos
Autofagia/fisiologia , Endocitose/fisiologia , Depressão Sináptica de Longo Prazo/fisiologia , Plasticidade Neuronal/fisiologia , Receptores de N-Metil-D-Aspartato/metabolismo , Sinapses/fisiologia , Animais , Autofagia/genética , Células Cultivadas , Hipocampo/citologia , Hipocampo/metabolismo , Hipocampo/fisiologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Neurônios/metabolismo , Neurônios/fisiologia , Técnicas de Cultura de Tecidos
15.
Aquat Toxicol ; 225: 105523, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32531534

RESUMO

Hexabromocyclododecane (HBCD) is a ubiquitous environmental contaminant of current concern despite its global ban in 2013 due to its characteristics as a persistent organic pollutant. While the toxicity of HBDC in vertebrates has been extensively studied, the specific molecular mechanisms underlying its toxicity in fish are not fully understood to date. Therefore, the aim of this work was to determine the in vitro cytotoxicity of HBCD in the fathead minnow (Pimephales promelas) using liver explants, and to investigate the molecular mechanisms underlying these effects. Explants were incubated with nine different concentrations of HBCD (0.00032, 0.0016, 0.008, 0.04, 0.2, 1, 5, 25 and 125 mg HBCD/L) for 6 and 24 h, and cytotoxicity was tested by using the Lactate Dehydrogenase (LDH) assay. The expression of genes with a key role in the regulation of apoptosis, oxidative stress, cryoprotective responses to reactive oxygen species (ROS), and xenobiotic metabolism was also measured in liver explants after exposure to 0.00032, 0.0016, 0.008, 0.2, and 25 mg HBCD/L. After 6 h, a concentration-dependent significant increase in cytotoxicity was found between 0.008 and 1 mg/L HBCD, followed by a decrease between 1 and 25 mg/L. Cytotoxicity reached 100 % at a concentration of 125 mg/L HBCD. After 24 h, HBCD showed a biphasic response with a concentration-dependent decrease in cytotoxicity between 0.0016 and 1 mg/L that returned to baseline levels at 5 mg/L. Then, cytotoxicity increased at concentrations greater than 5 mg/L to reach a maximum value at 125 mg/L. Changes in the expression of genes related to apoptosis (apoEn, apoIn, caspase2, caspase9 and bax) were also time- and concentration-dependent. Genes related to antioxidant responses such as gst and catalase were generally decreased after 6 h of incubation and increased after 24 h. The same pattern was observed for cyp1a and cyp3a, both related to xenobiotic metabolism. The expression of genes related to cryoprotective responses anti ROS (akt and pi3k) decreased at almost all HBCD concentrations tested after 6 h but remained unaltered after 24 h. Overall, we demonstrated that the cytotoxic effect of HBCD in fathead minnow liver explant was not proportional to its concentration in the culture media. Cytotoxicity was highly dynamic and did not follow a typical concentration-response pattern, complicating its toxicological characterization.


Assuntos
Cyprinidae , Hidrocarbonetos Bromados/toxicidade , Fígado/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Apoptose/efeitos dos fármacos , L-Lactato Desidrogenase/metabolismo , Fígado/metabolismo , Fígado/patologia , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Técnicas de Cultura de Tecidos
16.
Heart Rhythm ; 17(9): 1445-1451, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32479900

RESUMO

BACKGROUND: Early during the current coronavirus disease 19 (COVID-19) pandemic, hydroxychloroquine (HCQ) received a significant amount of attention as a potential antiviral treatment, such that it became one of the most commonly prescribed medications for COVID-19 patients. However, not only has the effectiveness of HCQ remained questionable, but mainly based on preclinical and a few small clinical studies, HCQ is known to be potentially arrhythmogenic, especially as a result of QT prolongation. OBJECTIVE: The purpose of this study was to investigate the arrhythmic effects of HCQ, as the heightened risk is especially relevant to COVID-19 patients, who are at higher risk for cardiac complications and arrhythmias at baseline. METHODS: An optical mapping technique utilizing voltage-sensitive fluorescent dyes was used to determine the arrhythmic effects of HCQ in ex vivo guinea pig and rabbit hearts perfused with the upper therapeutic serum dose of HCQ (1000 ng/mL). RESULTS: HCQ markedly increased action potential dispersion, resulted in development of repolarization alternans, and initiated polymorphic ventricular tachycardia. CONCLUSION: The study results further highlight the proarrhythmic effects of HCQ.


Assuntos
Antimaláricos/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Coração/efeitos dos fármacos , Coração/fisiopatologia , Hidroxicloroquina/farmacologia , Animais , Estimulação Cardíaca Artificial , Infecções por Coronavirus/tratamento farmacológico , Cobaias , Coração/diagnóstico por imagem , Coelhos , Técnicas de Cultura de Tecidos , Imagens com Corantes Sensíveis à Voltagem
17.
Nanotoxicology ; 14(6): 847-865, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32536243

RESUMO

To determine responses to nanoparticles in a more comprehensive way, current efforts in nanosafety aim at combining the analysis of multiple endpoints and comparing outcomes in different models. To this end, here we used tissue slices from mice as 3D ex vivo models and performed for the first time a comparative study of uptake and impact in liver, lung, and kidney slices exposed under the same conditions to silica, carboxylated and amino-modified polystyrene. In all organs, only exposure to amino-modified polystyrene induced toxicity, with stronger effects in kidneys and lungs. Uptake and distribution studies by confocal microscopy confirmed nanoparticle uptake in all slices, and, in line with what observed in vivo, preferential accumulation in the macrophages. However, uptake levels in kidneys were minimal, despite the strong impact observed when exposed to the amino-modified polystyrene. On the contrary, nanoparticle uptake and accumulation in macrophages were particularly evident in lung slices. Thus, tissue digestion was used to recover all cells from lung slices at different exposure times and to determine by flow cytometry detailed uptake kinetics in lung macrophages and all other cells, confirming higher uptake by the macrophages. Finally, the expression levels of a panel of targets involved in inflammation and macrophage polarization were measured to determine potential effects induced in lung and liver tissue. Overall, this comparative study allowed us to determine uptake and impact of nanoparticles in real tissue and identify important differences in outcomes in the organs in which nanoparticles distribute.


Assuntos
Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Nanopartículas/toxicidade , Poliestirenos/toxicidade , Animais , Feminino , Técnicas In Vitro , Inflamação , Rim/metabolismo , Fígado/metabolismo , Pulmão/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nanopartículas/metabolismo , Especificidade de Órgãos , Poliestirenos/metabolismo , Técnicas de Cultura de Tecidos , Distribuição Tecidual
18.
Nutr Metab Cardiovasc Dis ; 30(7): 1216-1226, 2020 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-32482454

RESUMO

BACKGROUND AND AIMS: Successful islet transplantation as a promising treatment of diabetes type 1 is threatened with the loss of islets during the pre-transplant culture due to hypoxia and oxidative stress-induced apoptosis. Therefore, optimization of culture in order to preserve the islets is a critical point. In this study, we investigated the effect of resveratrol, as a cytoprotective agent, on the cultured human islets. METHODS AND RESULTS: Isolated islets were treated with different concentrations of resveratrol for 24 and 72 h. Islets' viability, apoptosis, apoptosis markers, and insulin and C-peptide secretion, along with the production of reactive oxygen species (ROS), hypoxia inducible factor 1 alpha (HIF-1α), and its target genes in the islets were investigated. Our findings showed that the islets were exposed to hypoxia and oxidative stress after isolation and during culture. This insult induced apoptosis and decreased viability during 72 h. The presence of resveratrol significantly attenuated HIF-1α and ROS production, reduced apoptosis, promoted the VEGF secretion, and increased the insulin and C-peptide secretion. In this regard, resveratrol improved the islet's survival and function in the culture period. CONCLUSIONS: Using resveratrol can attenuate the stressful condition for the islets in the pre-transplant culture and subsequently ameliorate their viability and functionality that lead to successful outcome after clinical transplantation.


Assuntos
Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Ilhotas Pancreáticas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Resveratrol/farmacologia , Adulto , Idoso , Peptídeo C/metabolismo , Hipóxia Celular , Sobrevivência Celular/efeitos dos fármacos , Citoproteção , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/patologia , Pessoa de Meia-Idade , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Técnicas de Cultura de Tecidos , Fator A de Crescimento do Endotélio Vascular/metabolismo
19.
PLoS One ; 15(5): e0233075, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32407348

RESUMO

Simple limbal epithelial transplantation (SLET) and cultivated limbal epithelial transplantation (CLET) are proven techniques for treating limbal stem cell deficiency (LSCD). However, the precise regions that are most suitable for preparing explants for transplantation have not been identified conclusively. Accordingly, this in vitro study aimed at determining ideal sites to be selected for tissue harvest for limbal stem cell culture and transplantation. We evaluated cell outgrowth potential and the expression of stem cell markers in cultures from 48 limbal explants from five cadaveric donors. The limbal explants were generated from the three specific sites: Lcor (located innermost and adjacent to the cornea), Lm (middle limbus), and Lconj (located outermost adjacent to the conjunctiva). We found that explants from the Lconj and Lm sites exhibited higher growth potential than those from the Lcor site. Transcript encoding the stem cell marker and p63 isoform, ΔNp63, was detected in cells from Lm and Lconj explants; expression levels were slightly, though significantly (p-value < 0.05), higher in Lm than in Lconj, although expression of ΔNp63α protein was similar in cells from all explants. Differential expression of ATP-Binding Cassette Subfamily G Member 2 (ABCG2) did not reach statistical significance. Immunohistochemistry by indirect immunofluorescence analysis of limbus tissue revealed that the basal layer in explant tissue from Lconj and Lm contained markedly more stem cells than found in Lcor explant tissue; these findings correlate with a higher capacity for growth. Collectively, our findings suggest that explants from the Lconj and Lm sites should be selected for limbal cell expansion for both CLET and SLET procedures. These new insights may guide surgeons toward specific limbal sites that are most suitable for stem cell culture and transplantation and may ultimately improve treatment outcomes in the patients with LSCD.


Assuntos
Células-Tronco Adultas/citologia , Limbo da Córnea/citologia , Células-Tronco Adultas/metabolismo , Células-Tronco Adultas/transplante , Sequência de Aminoácidos , Biomarcadores/metabolismo , Cadáver , Técnicas de Cultura de Células , Proliferação de Células , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Células Epiteliais/transplante , Epitélio Anterior/citologia , Epitélio Anterior/lesões , Epitélio Anterior/metabolismo , Humanos , Técnicas In Vitro , Limbo da Córnea/lesões , Limbo da Córnea/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Técnicas de Cultura de Tecidos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
20.
PLoS One ; 15(5): e0233152, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32453755

RESUMO

Obesity is associated with significantly higher mortality rates, and excess adipose tissue is involved in respective pathologies. Here we established a human adipose tissue slice cultures (HATSC) model ex vivo. HATSC match the in vivo cell composition of human adipose tissue with, among others, mature adipocytes, mesenchymal stem cells as well as stroma tissue and immune cells. This is a new method, optimized for live imaging, to study adipose tissue and cell-based mechanisms of obesity in particular. HATSC survival was tested by means of conventional and immunofluorescence histological techniques, functional analyses and live imaging. Surgery-derived tissue was cut with a tissue chopper in 500 µm sections and transferred onto membranes building an air-liquid interface. HATSC were cultured in six-well plates filled with Dulbecco's Modified Eagle's Medium (DMEM), insulin, transferrin, and selenium, both with and without serum. After 0, 1, 7 and 14 days in vitro, slices were fixated and analyzed by morphology and Perilipin A for tissue viability. Immunofluorescent staining against IBA1, CD68 and Ki67 was performed to determine macrophage survival and proliferation. These experiments showed preservation of adipose tissue as well as survival and proliferation of monocytes and stroma tissue for at least 14 days in vitro even in the absence of serum. The physiological capabilities of adipocytes were functionally tested by insulin stimulation and measurement of Phospho-Akt on day 7 and 14 in vitro. Viability was further confirmed by live imaging using Calcein-AM (viable cells) and propidium iodide (apoptosis/necrosis). In conclusion, HATSC have been successfully established by preserving the monovacuolar form of adipocytes and surrounding macrophages and connective tissue. This model allows further analysis of mature human adipose tissue biology ex vivo.


Assuntos
Adipócitos , Tecido Adiposo , Modelos Biológicos , Obesidade , Técnicas de Cultura de Tecidos , Adipócitos/metabolismo , Adipócitos/patologia , Tecido Adiposo/metabolismo , Tecido Adiposo/patologia , Adolescente , Adulto , Idoso , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Sobrevivência Celular , Feminino , Humanos , Antígeno Ki-67/metabolismo , Masculino , Proteínas dos Microfilamentos/metabolismo , Pessoa de Meia-Idade , Obesidade/metabolismo , Obesidade/patologia
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