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1.
Arch Toxicol ; 98(3): 999-1014, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38212450

RESUMEN

Harmful algal blooms kill fish populations worldwide, as exemplified by the haptophyte microalga Prymnesium parvum. The suspected causative agents are prymnesins, categorized as A-, B-, and C-types based on backbone carbon atoms. Impacts of P. parvum extracts and purified prymnesins were tested on the epithelial rainbow trout fish gill cell line RTgill-W1 and on the human colon epithelial cells HCEC-1CT. Cytotoxic potencies ranked A > C > B-type with concentrations spanning from low (A- and C-type) to middle (B-type) nM ranges. Although RTgill-W1 cells were about twofold more sensitive than HCEC-1CT, the cytotoxicity of prymnesins is not limited to fish gills. Both cell lines responded rapidly to prymnesins; with EC50 values for B-types in RTgill-W1 cells of 110 ± 11 nM and 41.5 ± 0.6 nM after incubations times of 3 and 24 h. Results of fluorescence imaging and measured lytic effects suggest plasma membrane interactions. Postulating an osmotic imbalance as mechanisms of toxicity, incubations with prymnesins in media lacking either Cl-, Na+, or Ca2+ were performed. Cl- removal reduced morphometric rearrangements observed in RTgill-W1 and cytotoxicity in HCEC-1CT cells. Ca2+-free medium in RTgill-W1 cells exacerbated effects on the cell nuclei. Prymnesin composition of different P. parvum strains showed that analog composition within one type scarcely influenced the cytotoxic potential, while analog type potentially dictate potency. Overall, A-type prymnesins were the most potent ones in both cell lines followed by the C-types, and lastly B-types. Disturbance of Ca2+ and Cl- ionoregulation may be integral to prymnesin toxicity.


Asunto(s)
Colestenos , Haptophyta , Lipoproteínas , Animales , Humanos , Branquias , Línea Celular , Células Epiteliales , Colon
2.
Nano Lett ; 23(16): 7758-7766, 2023 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-37433061

RESUMEN

The intestinal compartment ensures nutrient absorption and barrier function against pathogens. Despite decades of research on the complexity of the gut, the adaptive potential to physical cues, such as those derived from interaction with particles of different shapes, remains less understood. Taking advantage of the technological versatility of silica nanoparticles, spherical, rod-shaped, and virus-like materials were synthesized. Morphology-dependent interactions were studied on differentiated Caco-2/HT29-MTX-E12 cells. Contributions of shape, aspect ratio, surface roughness, and size were evaluated considering the influence of the mucus layer and intracellular uptake pathways. Small particle size and surface roughness favored the highest penetration through the mucus but limited interaction with the cell monolayer and efficient internalization. Particles of a larger aspect ratio (rod-shaped) seemed to privilege paracellular permeation and increased cell-cell distances, albeit without hampering barrier integrity. Inhibition of clathrin-mediated endocytosis and chemical modulation of cell junctions effectively tuned these responses, confirming morphology-specific interactions elicited by bioinspired silica nanomaterials.


Asunto(s)
Mucosa Intestinal , Nanopartículas , Humanos , Células CACO-2 , Mucosa Intestinal/metabolismo , Dióxido de Silicio/metabolismo , Transporte Biológico
3.
Cell Commun Signal ; 21(1): 307, 2023 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-37904178

RESUMEN

Bladder cells face a challenging biophysical environment: mechanical cues originating from urine flow and regular contraction to enable the filling voiding of the organ. To ensure functional adaption, bladder cells rely on high biomechanical compliance, nevertheless aging or chronic pathological conditions can modify this plasticity. Obviously the cytoskeletal network plays an essential role, however the contribution of other, closely entangled, intracellular organelles is currently underappreciated. The endoplasmic reticulum (ER) lies at a crucial crossroads, connected to both nucleus and cytoskeleton. Yet, its role in the maintenance of cell mechanical stability is less investigated. To start exploring these aspects, T24 bladder cancer cells were treated with the ER stress inducers brefeldin A (10-40nM BFA, 24 h) and thapsigargin (0.1-100nM TG, 24 h). Without impairment of cell motility and viability, BFA and TG triggered a significant subcellular redistribution of the ER; this was associated with a rearrangement of actin cytoskeleton. Additional inhibition of actin polymerization with cytochalasin D (100nM CytD) contributed to the spread of the ER toward cell periphery, and was accompanied by an increase of cellular stiffness (Young´s modulus) in the cytoplasmic compartment. Shrinking of the ER toward the nucleus (100nM TG, 2 h) was related to an increased stiffness in the nuclear and perinuclear areas. A similar short-term response profile was observed also in normal human primary bladder fibroblasts. In sum, the ER and its subcellular rearrangement seem to contribute to the mechanical properties of bladder cells opening new perspectives in the study of the related stress signaling cascades. Video Abstract.


Asunto(s)
Retículo Endoplásmico , Vejiga Urinaria , Humanos , Estrés del Retículo Endoplásmico , Citoesqueleto , Tapsigargina/farmacología
4.
Arch Toxicol ; 97(1): 217-233, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36214828

RESUMEN

Bladder cells are constantly exposed to multiple xenobiotics and bioactive metabolites. In addition to this challenging chemical environment, they are also exposed to shear stress originating from urine and interstitial fluids. Hence, physiological function of bladder cells relies on a high biochemical and biomechanical adaptive competence, which, in turn, is largely supported via autophagy-related mechanisms. As a negative side of this plasticity, bladder cancer cells are known to adapt readily to chemotherapeutic programs. At the molecular level, autophagy was described to support resistance against pharmacological treatments and to contribute to the maintenance of cell structure and metabolic competence. In this study, we enhanced autophagy with rapamycin (1-100 nM) and assessed its effects on the motility of bladder cells, as well as the capability to respond to shear stress. We observed that rapamycin reduced cell migration and the mechanical-induced translocation potential of Krüppel-like transcription factor 2 (KLF2). These effects were accompanied by a rearrangement of cytoskeletal elements and mitochondrial loss. In parallel, intracellular acetylation levels were decreased. Mechanistically, inhibition of the NAD + -dependent deacetylase sirtuin-1 (SIRT1) with nicotinamide (NAM; 0.1-5 mM) restored acetylation levels hampered by rapamycin and cell motility. Taken together, we described the effects of rapamycin on cytoskeletal elements crucial for mechanotransduction and the dependency of these changes on the mitochondrial turnover caused by autophagy activation. Additionally, we could show that targeted metabolic intervention could revert the outcome of autophagy activation, reinforcing the idea that bladder cells can easily adapt to multiple xenobiotics and circumvent in this way the effects of single chemicals.


Asunto(s)
Neoplasias de la Vejiga Urinaria , Vejiga Urinaria , Humanos , Vejiga Urinaria/metabolismo , Mecanotransducción Celular , Acetilación , Xenobióticos/metabolismo , Autofagia , Neoplasias de la Vejiga Urinaria/metabolismo , Sirtuina 1/metabolismo , Sirolimus/farmacología
5.
Sensors (Basel) ; 23(7)2023 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-37050585

RESUMEN

Staphylococcus epidermidis (S. epidermidis) belongs to methicillin-resistant bacteria strains that cause severe disease in humans. Herein, molecularly imprinted polymer (MIP) nanoparticles resulting from solid-phase synthesis on entire cells were employed as a sensing material to identify the species. MIP nanoparticles revealed spherical shapes with diameters of approximately 70 nm to 200 nm in scanning electron microscopy (SEM), which atomic force microscopy (AFM) confirmed. The interaction between nanoparticles and bacteria was assessed using height image analysis in AFM. Selective binding between MIP nanoparticles and S. epidermidis leads to uneven surfaces on bacteria. The surface roughness of S. epidermidis cells was increased to approximately 6.3 ± 1.2 nm after binding to MIP nanoparticles from around 1 nm in the case of native cells. This binding behavior is selective: when exposing Escherichia coli and Bacillus subtilis to the same MIP nanoparticle solutions, one cannot observe binding. Fluorescence microscopy confirms both sensitivity and selectivity. Hence, the developed MIP nanoparticles are a promising approach to identify (pathogenic) bacteria species.


Asunto(s)
Impresión Molecular , Nanopartículas , Humanos , Polímeros/química , Impresión Molecular/métodos , Nanopartículas/química , Polímeros Impresos Molecularmente , Microscopía de Fuerza Atómica
6.
Toxicol Appl Pharmacol ; 446: 116034, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35461954

RESUMEN

In order to ensure barrier function, intestinal cells need to respond promptly to biomechanical stimulation and to adapt constantly to physical cues. To this aim, cell membranes are essential and rely extensively on lipid metabolism and turnover. These can be tuned via nutrition, pharmacological treatment, or exposure to xenobiotics, however, knowledge on the impact of lifestyle and diet on intestinal cells' biomechanical compliance is relatively limited. Building on this, two intestinal cell models (non-transformed human colon epithelial cells HCEC-1CT and the colon adenocarcinoma cell line HT-29) were systematically compared in terms of cholesterol content, membrane fluidity, actin cytoskeletal organization, expression of mechano-gated PIEZO1 channels and caveolin-1. Biomechanical compliance was evaluated with the application of fluid shear stress (force response 0.75-1.5 dyn/cm2). As model substances the food contaminant mycotoxin alternariol (AOH, 0.01-10 µM) was chosen in virtue of its putative structural analogy with cholesterol. AOH was compared to the cholesterol lowering agent lovastatin (LOVA, 0.01-10 µM) and to water-soluble cholesterol (MßCD-CHOL, 0.01-10 µg/ml). Exposure to AOH, LOVA and MßCD-CHOL coherently modulated membrane cholesterol, expression of PIEZO1 and caveolin-1 as well as the formation of actin stress fibers. These effects were functionally relevant since they modified the force response profile to fluid shear stress (morphological adaption and [Ca2+]i). In sum, we could demonstrate a novel role for exogenous or endogenous molecules in shaping intestinal mechanotransduction via regulation of cholesterol homeostasis and plasma membrane architecture.


Asunto(s)
Adenocarcinoma , Membrana Celular , Neoplasias del Colon , Mucosa Intestinal , Mecanotransducción Celular , Actinas/metabolismo , Adenocarcinoma/metabolismo , Caveolina 1/metabolismo , Membrana Celular/química , Membrana Celular/metabolismo , Colesterol/metabolismo , Neoplasias del Colon/metabolismo , Contaminación de Alimentos , Células HT29 , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/fisiología , Canales Iónicos/metabolismo , Lactonas/farmacología , Mecanotransducción Celular/fisiología , Resistencia al Corte
7.
Arch Toxicol ; 95(6): 2201-2221, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33890134

RESUMEN

Deoxynivalenol (vomitoxin, DON) is a secondary metabolite produced by Fusarium spp. fungi and it is one of the most prevalent mycotoxins worldwide. Crop infestation results not only in food and feed contamination, but also in direct dermal exposure, especially during harvest and food processing. To investigate the potential dermotoxicity of DON, epidermoid squamous cell carcinoma cells A431 were compared to primary human neonatal keratinocytes (HEKn) cells via proteome/phosphoproteome profiling. In A431 cells, 10 µM DON significantly down-regulated ribosomal proteins, as well as mitochondrial respiratory chain elements (OXPHOS regulation) and transport proteins (TOMM22; TOMM40; TOMM70A). Mitochondrial impairment was reflected in altered metabolic competence, apparently combined with interference of the lipid biosynthesis machinery. Functional effects on the cell membrane were confirmed by live cell imaging and membrane fluidity assays (0.1-10 µM DON). Moreover, a common denominator for both A431 and HEKn cells was a significant downregulation of the squalene synthase (FDFT1). In sum, proteome alterations could be traced back to the transcription factor Klf4, a crucial regulator of skin barrier function. Overall, these results describe decisive molecular events sustaining the capability of DON to impair skin barrier function. Proteome data generated in the study are fully accessible via ProteomeXchange with the accession numbers PXD011474 and PXD013613.


Asunto(s)
Células Epidérmicas/efectos de los fármacos , Queratinocitos/efectos de los fármacos , Lípidos/biosíntesis , Tricotecenos/toxicidad , Carcinoma de Células Escamosas/metabolismo , Línea Celular Tumoral , Células Cultivadas , Relación Dosis-Respuesta a Droga , Células Epidérmicas/patología , Fusarium/metabolismo , Humanos , Queratinocitos/patología , Mitocondrias/efectos de los fármacos , Mitocondrias/patología , Proteómica , Metabolismo Secundario , Tricotecenos/administración & dosificación , Tricotecenos/aislamiento & purificación
9.
Biomed Pharmacother ; 170: 115942, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38042111

RESUMEN

Bladder cancer cells possess unique adaptive capabilities: shaped by their environment, cells face a complex chemical mixture of metabolites and xenobiotics accompanied by physiological mechanical cues. These responses might translate into resistance to chemotherapeutical regimens and can largely rely on autophagy. Considering molecules capable of rewiring tumor plasticity, compounds of natural origin promise to offer valuable options. Fungal derived metabolites, such as bafilomycin and wortmannin are widely acknowledged as autophagy inhibitors. Here, their potential to tune bladder cancer cells´ adaptability to chemical and physical stimuli was assessed. Additionally, dietary occurring mycotoxins were also investigated, namely deoxynivalenol (DON, 0.1-10 µM) and fusaric acid (FA, 0.1-1 mM). Endowing a Janus' face behavior, DON and FA are on the one side described as toxins with detrimental health effects. Concomitantly, they are also explored experimentally for selective pharmacological applications including anticancer activities. In non-cytotoxic concentrations, bafilomycin (BAFI, 1-10 nM) and wortmannin (WORT, 1 µM) modified cell morphology and reduced cancer cell migration. Application of shear stress and inhibition of mechano-gated PIEZO channels reduced cellular sensitivity to BAFI treatment (1 nM). Similarly, for FA (0.5 mM) PIEZO1 expression and inhibition largely aligned with the modulatory potential on cancer cells motility. Additionally, this study highlighted that the activity profile of compounds with similar cytotoxic potential (e.g. co-incubation DON with BAFI or FA with WORT) can diverge substantially in the regulation of cell mechanotransduction. Considering the interdependence between tumor progression and response to mechanical cues, these data promise to provide a novel viewpoint for the study of chemoresistance and associated pathways.


Asunto(s)
Antineoplásicos , Neoplasias de la Vejiga Urinaria , Humanos , Mecanotransducción Celular , Wortmanina/farmacología , Autofagia , Antineoplásicos/farmacología , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Canales Iónicos
10.
Toxicol Lett ; 358: 88-99, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35104616

RESUMEN

Several Alternaria mycotoxins are believed to act as endocrine disruptive chemicals (EDCs), since they are reported to bind estrogen receptors in several experimental models. After ingestion of contaminated food commodities, the mycotoxins reach the intestine, where they come into direct contact with food constituents as well as the gut microbiota. Thus, the aim of the present work was to evaluate the modulatory potential of a complex extract of cultured Alternaria fungi (CE; containing eleven chemically characterized compounds) on the estrogenic signaling cascade of mammalian cells before and after anaerobic incubation with fecal slurries, in order to simulate an in vivo-like condition in the gut. Assessing alkaline phosphatase expression in Ishikawa cells as a measure for estrogenicity, we found the CE to partially quench the intrinsic estrogenic properties of fecal slurries and fecal waters, even after 3 h of fecal incubation. Investigation of the mechanisms underlying the effects observed carried out through an in vitro/in silico approach revealed the ability of the extract to decrease the ERα/ERß nuclear ratio, while a possible action of the mycotoxins as ER-antagonists was excluded. Our results suggest that Alternaria mycotoxins might act as EDCs in vivo, and warrant further investigation in animal models.


Asunto(s)
Micotoxinas , Alternaria/metabolismo , Anaerobiosis , Animales , Estrógenos/metabolismo , Heces/química , Contaminación de Alimentos/análisis , Humanos , Lactonas/metabolismo , Mamíferos/metabolismo , Micotoxinas/metabolismo
11.
J Colloid Interface Sci ; 610: 1027-1034, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-34920862

RESUMEN

Most MOFs are non-cubic, with functionality dependent upon crystallographic direction, and are largely prepared as microcrystalline powders. Therefore, general methods to orient and assemble free-standing MOF crystals are especially important and urgently needed. This is addressed here through the novel strategy of E-field assisted liquid crystal assembly, applied to MIL-53-NH2(Al), MIL-68(In) and NU-1000 MOF crystals, with aspect ratios ranging from 10 to 1.2, to form highly oriented MOF superstructures which were photopolymerized to fix their long-ranged order. This new strategy for controlling MOF orientation and packing side-steps the traditional requirements of particle monodispersity, shape homogeneity and high aspect ratios (>4.7) typical of colloidal and liquid crystal assembly, and is applicable even to polydispersed MOF crystals, thereby paving the way towards the development of highly oriented MOF composites with improved functionality.

12.
J Biol Chem ; 285(53): 41765-71, 2010 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-20966075

RESUMEN

The plasma membrane has been hypothesized to contain nanoscopic lipid platforms, which are discussed in the context of "lipid rafts" or "membrane rafts." Based on biochemical and cell biological studies, rafts are believed to play a crucial role in many signaling processes. However, there is currently not much information on their size, shape, stability, surface density, composition, and heterogeneity. We present here a method that allows for the first time the direct imaging of nanoscopic long-lived platforms with raft-like properties diffusing in the live cell plasma membrane. Our method senses these platforms by their property to assemble a characteristic set of fluorescent marker proteins or lipids on a time scale of seconds. A special photobleaching protocol was used to reduce the surface density of labeled mobile platforms down to the level of well isolated diffraction-limited spots without altering the single spot brightness. The statistical distribution of probe molecules per platform was determined by single molecule brightness analysis. For demonstration, we used the consensus raft marker glycosylphosphatidylinositol-anchored monomeric GFP and the fluorescent lipid analog BODIPY-G(M1), which preferentially partitions into liquid-ordered phases. For both markers, we found cholesterol-dependent homo-association in the plasma membrane of living CHO and Jurkat T cells in the resting state, thereby demonstrating the existence of small, mobile, long-lived platforms containing these probes. We further applied the technology to address structural changes in the plasma membrane during fever-type heat shock: at elevated temperatures, the glycosylphosphatidylinositol-anchored monomeric GFP homo-association disappeared, accompanied by an increase in the expression of the small heat shock protein Hsp27.


Asunto(s)
Membrana Celular/metabolismo , Glicosilfosfatidilinositoles/química , Microscopía/métodos , Nanoestructuras/química , Nanotecnología/métodos , Animales , Colesterol/química , Cricetinae , Cricetulus , Difusión , Proteínas Fluorescentes Verdes/química , Humanos , Células Jurkat , Microdominios de Membrana/química , Propiedades de Superficie
13.
Cell Mol Life Sci ; 67(10): 1661-74, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20140748

RESUMEN

Estrogen plays a critical regulatory role in the development and maintenance of immunity. Its role in the regulation of antibody synthesis in vivo is still not completely clear. Here, we have compared the effect of estrogen on T cell-dependent (TD) and T cell-independent type 2 (TI-2) antibody responses. The results provide the first evidence that estrogen enhances the TD but not the TI-2 response. Ovariectomy significantly decreased, while estrogen re-administration increased the number of hapten-specific IgM- and IgG-producing cells in response to TD antigen. In vitro experiments also show that estrogen may have a direct impact on B and T cells by inducing rapid signaling events, such as Erk and AKT phosphorylation, cell-specific Ca(2+) signal, and NFkappaB activation. These non-transcriptional effects are mediated by classical estrogen receptors and partly by an as yet unidentified plasma membrane estrogen receptor. Such receptor- mediated rapid signals may modulate the in vivo T cell-dependent immune response.


Asunto(s)
Estradiol/farmacología , Inmunidad/efectos de los fármacos , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Animales , Formación de Anticuerpos/efectos de los fármacos , Linfocitos B/citología , Linfocitos B/efectos de los fármacos , Linfocitos B/enzimología , Linfocitos B/inmunología , Señalización del Calcio/efectos de los fármacos , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Activación Enzimática/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Femenino , Interferón gamma/genética , Ratones , Ratones Endogámicos C57BL , FN-kappa B/metabolismo , Ovariectomía , Fosforilación/efectos de los fármacos , Transporte de Proteínas/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptores de Estrógenos/metabolismo , Linfocitos T/citología , Linfocitos T/enzimología , Transcripción Genética/efectos de los fármacos
14.
Front Pharmacol ; 12: 647350, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34012396

RESUMEN

Accumulation of xenobiotics and waste metabolites in the urinary bladder is constantly accompanied by shear stress originating from the movement of the luminal fluids. Hence, both chemical and physical cues constantly modulate the cellular response in health and disease. In line, bladder cells have to maintain elevated mechanosensory competence together with chemical stress response adaptation potential. However, much of the molecular mechanisms sustaining this plasticity is currently unknown. Taking this as a starting point, we investigated the response of T24 urinary bladder cancer cells to shear stress comparing morphology to functional performance. T24 cells responded to the shear stress protocol (flow speed of 0.03 ml/min, 3 h) by significantly increasing their surface area. When exposed to deoxynivalenol-3-sulfate (DON-3-Sulf), bladder cells increased this response in a concentration-dependent manner (0.1-1 µM). DON-3-Sulf is a urinary metabolite of a very common food contaminant mycotoxin (deoxynivalenol, DON) and was already described to enhance proliferation of cancer cells. Incubation with DON-3-Sulf also caused the enlargement of the endoplasmic reticulum (ER), decreased the lysosomal movement, and increased the formation of actin stress fibers. Similar remodeling of the endoplasmic reticulum and area spread after shear stress were observed upon incubation with the autophagy activator rapamycin (1-100 nM). Performance of experiments in the presence of chloroquine (chloroquine, 30 µM) further contributed to shed light on the mechanistic link between adaptation to the biomechanical stimulation and ER stress response. At the molecular level, we observed that ER reshaping was linked to actin organization, with the two components mutually regulating each other. Indeed, we identified in the ER stress-cytoskeletal rearrangement an important axis defining the physical/chemical response potential of bladder cells and created a workflow for further investigation of urinary metabolites, food constituents, and contaminants, as well as for pharmacological profiling.

15.
Front Oncol ; 11: 746411, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35251951

RESUMEN

With the onset of resistance, ovarian cancer cells display almost unpredictable adaptive potential. This may derive from the tumor genetic ancestry and can be additionally tailored by post translational protein modifications (PTMs). In this study, we took advantage of high-end (phospho)-proteome analysis combined with multiparametric morphometric profiling in high-grade serous (OVCAR-3) and non-serous (SKOV-3) ovarian carcinoma cells. For functional experiments, we applied two different protocols, representing typical conditions of the abdominal cavity and of the growing tumor tissue: on the one side hypoxia (oxygen 1%) which develops within the tumor mass or is experienced during migration/extravasation in non-vascularized areas. On the other hand, fluid shear stress (250 rpm, 2.8 dyn/cm2) which affects tumor surface in the peritoneum or metastases in the bloodstream. After 3 hours incubation, treatment groups were clearly distinguishable by PCA analysis. Whereas basal proteome profiles of OVCAR-3 and SKOV-3 cells appeared almost unchanged, phosphoproteome analysis revealed multiple regulatory events. These affected primarily cellular structure and proliferative potential and consolidated in the proteome signature after 24h treatment. Upon oxygen reduction, metabolism switched toward glycolysis (e.g. upregulation hexokinase-2; HK2) and cell size increased, in concerted regulation of pathways related to Rho-GTPases and/or cytoskeletal elements, resembling a vasculogenic mimicry response. Shear stress regulated proteins governing cell cycle and structure, as well as the lipid metabolism machinery including the delta(14)-sterol reductase, kinesin-like proteins (KIF-22/20A) and the actin-related protein 2/3 complex. Independent microscopy-based validation experiments confirmed cell-type specific morphometric responses. In conclusion, we established a robust workflow enabling the description of the adaptive potential of ovarian cancer cells to physical and chemical stressors typical for the abdominal cavity and supporting the identification of novel molecular mechanisms sustaining tumor plasticity and pharmacologic resistance.

16.
Cytometry A ; 73(7): 599-614, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18473380

RESUMEN

The evolutionarily developed microdomain structure of biological membranes has gained more and more attention in the past decade. The caveolin-free "membrane rafts," the caveolin-expressing rafts (caveolae), as well as other membrane microdomains seem to play an essential role in controlling and coordinating cell-surface molecular recognition, internalization/endocytosis of the bound molecules or pathogenic organisms and in regulation of transmembrane signal transduction processes. Therefore, in many research fields (e.g. neurobiology and immunology), there is an ongoing need to understand the nature of these microdomains and to quantitatively characterize their lipid and protein composition under various physiological and pathological conditions. Flow and image cytometry offer many sophisticated and routine tools to study these questions. In this review, we give an overview of the past efforts to detect and characterize these membrane microdomains by the use of classical cytometric technologies, and finally we will discuss the results and perspectives of a new line of raft cytometry, the "high throughput screening assays of membrane microdomains," based on "lipidomic" and "proteomic" approaches.


Asunto(s)
Caveolas/química , Citometría de Flujo/métodos , Lípidos de la Membrana/química , Microdominios de Membrana/química , Proteómica/métodos , Animales , Membrana Celular/metabolismo , Detergentes/farmacología , Transferencia Resonante de Energía de Fluorescencia/métodos , Humanos , Citometría de Imagen/métodos , Lípidos/química , Estructura Terciaria de Proteína
17.
Fogorv Sz ; 101(2): 71-3, 2008 Apr.
Artículo en Húngaro | MEDLINE | ID: mdl-18664098

RESUMEN

AIMS: For the replacement of dental deficiencies when the difference in axis between the future abutment teeth is considerable and preparation of a fixed bridge-prosthesis is planned without the sacrifice of too much extra dental tissue, one possibility is to prepare fixed separated dentures with nonrigid connectors. METHODS: From 1999 to 2007, we prepared such dentures, initially using intracoronal retainers in accordance with the literature, after that we positioned the retainers extracoronally whenever this was possible. RESULTS: In 35 cases we prepared multi-unit fixed prostheses with a total of 43 retainers. These segmented prostheses could be fixed rigidly after cementation. All of them remain in place without any complaint. CONCLUSION: Fixed dentures prepared with extracoronal retainers proved safe and esthetic and extra dental tissue is not sacrificed.


Asunto(s)
Pilares Dentales , Diseño de Dentadura , Dentadura Parcial Fija , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
18.
eNeuro ; 5(5)2018.
Artículo en Inglés | MEDLINE | ID: mdl-30406179

RESUMEN

Immune challenge alters neural functioning via cytokine production. Inflammation has profound impact on the central regulation of fertility, but the mechanisms involved are not clearly defined. The anti-inflammatory cytokine interleukin (IL)-10 is responsible for balancing the immune response in the brain. To examine whether IL-10 has an effect on the function of the gonadotropin-releasing hormone (GnRH) neurons, we first examined the effect of immune responses with distinct cytokine profiles, such as the T cell-dependent (TD) and T cell-independent (TI) B-cell response. We investigated the effect of the TD and TI immune responses on ERK1/2 phosphorylation in GnRH neurons by administering fluorescein isothiocyanate/keyhole limpet hemocyanin (KLH-FITC) or dextran-FITC to female mice. Although dextran-FITC had no effect, KLH-FITC induced ERK1/2 phosphorylation in GnRH neurons after 6 d. KLH-FITC treatment increased the levels of IL-10 in the hypothalamus (HYP), but this treatment did not cause lymphocyte infiltration or an increase in the levels of proinflammatory cytokines. In IL-10 knock-out (KO) mice, KLH-FITC-induced ERK1/2 phosphorylation in the GnRH neurons was absent. We also showed that in IL-10 KO mice, the estrous cycle was disrupted. Perforated patch-clamp recordings from GnRH-GFP neurons, IL-10 immunohistochemistry, and in vitro experiments on acute brain slices revealed that IL-10 can directly alter GnRH neuron firing and induce ERK1/2 phosphorylation. These observations demonstrate that IL-10 plays a role in influencing signaling of GnRH neurons in the TD immune response. These results also provide the first evidence that IL-10 can directly alter the function of GnRH neurons and may help the maintenance of the integrity of the estrous cycle.


Asunto(s)
Hormona Liberadora de Gonadotropina/inmunología , Hipotálamo/efectos de los fármacos , Interleucina-10/inmunología , Neuronas/inmunología , Animales , Citocinas/inmunología , Estradiol/inmunología , Estradiol/farmacología , Ciclo Estral/inmunología , Femenino , Hipotálamo/inmunología , Interleucina-10/genética , Ratones Endogámicos C57BL , Ratones Noqueados , Transducción de Señal/efectos de los fármacos , Transducción de Señal/inmunología
19.
Cell Rep ; 24(10): 2746-2756.e5, 2018 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-30184507

RESUMEN

Adipocytes, once considered simple lipid-storing cells, are rapidly emerging as complex cells with many biologically diverse functions. A powerful high-throughput method for analyzing single cells is flow cytometry. Several groups have attempted to analyze and sort freshly isolated adipocytes; however, using an adipocyte-specific reporter mouse, we demonstrate that these studies fail to detect the majority of white adipocytes. We define critical settings required for adipocyte flow cytometry and provide a rigid strategy for analyzing and sorting white and brown adipocyte populations. The applicability of our protocol is shown by sorting mouse adipocytes based on size or UCP1 expression and demonstrating that a subset of human adipocytes lacks the ß2-adrenergic receptor, particularly in the insulin-resistant state. In conclusion, the present study confers key technological insights for analyzing and sorting mature adipocytes, opening up numerous downstream research applications.


Asunto(s)
Adipocitos/citología , Adipocitos/metabolismo , Citometría de Flujo/métodos , Tejido Adiposo/citología , Tejido Adiposo/metabolismo , Tejido Adiposo Pardo/citología , Tejido Adiposo Pardo/metabolismo , Tejido Adiposo Blanco/citología , Tejido Adiposo Blanco/metabolismo , Animales , Humanos , Ratones , Proteína Desacopladora 1/metabolismo
20.
Nat Commun ; 9(1): 5068, 2018 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-30498206

RESUMEN

Methylation patterns of circulating cell-free DNA (cfDNA) contain rich information about recent cell death events in the body. Here, we present an approach for unbiased determination of the tissue origins of cfDNA, using a reference methylation atlas of 25 human tissues and cell types. The method is validated using in silico simulations as well as in vitro mixes of DNA from different tissue sources at known proportions. We show that plasma cfDNA of healthy donors originates from white blood cells (55%), erythrocyte progenitors (30%), vascular endothelial cells (10%) and hepatocytes (1%). Deconvolution of cfDNA from patients reveals tissue contributions that agree with clinical findings in sepsis, islet transplantation, cancer of the colon, lung, breast and prostate, and cancer of unknown primary. We propose a procedure which can be easily adapted to study the cellular contributors to cfDNA in many settings, opening a broad window into healthy and pathologic human tissue dynamics.


Asunto(s)
Ácidos Nucleicos Libres de Células/genética , Algoritmos , Biomarcadores de Tumor/genética , Neoplasias de la Mama/genética , Células Cultivadas , Neoplasias del Colon/genética , Islas de CpG/genética , Metilación de ADN/genética , Células Endoteliales/metabolismo , Eritrocitos/metabolismo , Hepatocitos/metabolismo , Humanos , Leucocitos/metabolismo , Neoplasias Pulmonares/genética , Regiones Promotoras Genéticas/genética , Sepsis/genética
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