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1.
Biomater Biosyst ; 14: 100093, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38585282

RESUMEN

Recently, it has been recognized that physical abnormalities (e.g. elevated solid stress, elevated interstitial fluid pressure, increased stiffness) are associated with tumor progression and development. Additionally, these mechanical forces originating from tumor cell environment through mechanotransduction pathways can affect metabolism. On the other hand, mitochondria are well-known as bioenergetic, biosynthetic, and signaling organelles crucial for sensing stress and facilitating cellular adaptation to the environment and physical stimuli. Disruptions in mitochondrial dynamics and function have been found to play a role in the initiation and advancement of cancer. Consequently, it is logical to hypothesize that mitochondria dynamics subjected to physical cues may play a pivotal role in mediating tumorigenesis. Recently mitochondrial biogenesis and turnover, fission and fusion dynamics was linked to mechanotransduction in cancer. However, how cancer cell mechanics and mitochondria functions are connected, still remain poorly understood. Here, we discuss recent studies that link mechanical stimuli exerted by the tumor cell environment and mitochondria dynamics and functions. This interplay between mechanics and mitochondria functions may shed light on how mitochondria regulate tumorigenesis.

2.
Exp Mol Med ; 55(9): 2005-2024, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37653039

RESUMEN

The lack of physiological parity between 2D cell culture and in vivo culture has led to the development of more organotypic models, such as organoids. Organoid models have been developed for a number of tissues, including the liver. Current organoid protocols are characterized by a reliance on extracellular matrices (ECMs), patterning in 2D culture, costly growth factors and a lack of cellular diversity, structure, and organization. Current hepatic organoid models are generally simplistic and composed of hepatocytes or cholangiocytes, rendering them less physiologically relevant compared to native tissue. We have developed an approach that does not require 2D patterning, is ECM independent, and employs small molecules to mimic embryonic liver development that produces large quantities of liver-like organoids. Using single-cell RNA sequencing and immunofluorescence, we demonstrate a liver-like cellular repertoire, a higher order cellular complexity, presenting with vascular luminal structures, and a population of resident macrophages: Kupffer cells. The organoids exhibit key liver functions, including drug metabolism, serum protein production, urea synthesis and coagulation factor production, with preserved post-translational modifications such as N-glycosylation and functionality. The organoids can be transplanted and maintained long term in mice producing human albumin. The organoids exhibit a complex cellular repertoire reflective of the organ and have de novo vascularization and liver-like function. These characteristics are a prerequisite for many applications from cellular therapy, tissue engineering, drug toxicity assessment, and disease modeling to basic developmental biology.


Asunto(s)
Hígado , Organoides , Humanos , Animales , Ratones , Ingeniería de Tejidos , Hepatocitos , Células Cultivadas
3.
Nanoscale Adv ; 5(16): 4250-4268, 2023 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-37560414

RESUMEN

Iron oxide nanoparticles (IONPs) are being actively researched in various biomedical applications, particularly as magnetic resonance imaging (MRI) contrast agents for diagnosing various liver pathologies like nonalcoholic fatty liver diseases, nonalcoholic steatohepatitis, and cirrhosis. Emerging evidence suggests that IONPs may exacerbate hepatic steatosis and liver injury in susceptible livers such as those with nonalcoholic fatty liver disease. However, our understanding of how IONPs may affect steatotic cells at the sub-cellular level is still fragmented. Generally, there is a lack of studies identifying the molecular mechanisms of potential toxic and/or adverse effects of IONPs on "non-heathy" in vitro models. In this study, we demonstrate that IONPs, at a dose that does not cause general toxicity in hepatic cells (Alexander and HepG2), induce significant toxicity in steatotic cells (cells loaded with non-toxic doses of palmitic acid). Mechanistically, co-treatment with PA and IONPs resulted in endoplasmic reticulum (ER) stress, accompanied by the release of cathepsin B from lysosomes to the cytosol. The release of cathepsin B, along with ER stress, led to the activation of apoptotic cell death. Our results suggest that it is necessary to consider the interaction between IONPs and the liver, especially in susceptible livers. This study provides important basic knowledge for the future optimization of IONPs as MRI contrast agents for various biomedical applications.

4.
Sci Rep ; 13(1): 10818, 2023 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-37402779

RESUMEN

Dramatically increased levels of electromagnetic radiation in the environment have raised concerns over the potential health hazards of electromagnetic fields. Various biological effects of magnetic fields have been proposed. Despite decades of intensive research, the molecular mechanisms procuring cellular responses remain largely unknown. The current literature is conflicting with regards to evidence that magnetic fields affect functionality directly at the cellular level. Therefore, a search for potential direct cellular effects of magnetic fields represents a cornerstone that may propose an explanation for potential health hazards associated with magnetic fields. It has been proposed that autofluorescence of HeLa cells is magnetic field sensitive, relying on single-cell imaging kinetic measurements. Here, we investigate the magnetic field sensitivity of an endogenous autofluorescence in HeLa cells. Under the experimental conditions used, magnetic field sensitivity of an endogenous autofluorescence was not observed in HeLa cells. We present a number of arguments indicating why this is the case in the analysis of magnetic field effects based on the imaging of cellular autofluorescence decay. Our work indicates that new methods are required to elucidate the effects of magnetic fields at the cellular level.


Asunto(s)
Campos Electromagnéticos , Campos Magnéticos , Humanos , Células HeLa
5.
Adv Drug Deliv Rev ; 197: 114828, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37075952

RESUMEN

Although several nanomedicines got clinical approval over the past two decades, the clinical translation rate is relatively small so far. There are many post-surveillance withdrawals of nanomedicines caused by various safety issues. For successful clinical advancement of nanotechnology, it is of unmet need to realize cellular and molecular foundation of nanotoxicity. Current data suggest that lysosomal dysfunction caused by nanoparticles is emerging as the most common intracellular trigger of nanotoxicity. This review analyzes prospect mechanisms of lysosomal dysfunction-mediated toxicity induced by nanoparticles. We summarized and critically assessed adverse drug reactions of current clinically approved nanomedicines. Importantly, we show that physicochemical properties have great impact on nanoparticles interaction with cells, excretion route and kinetics, and subsequently on toxicity. We analyzed literature on adverse reactions of current nanomedicines and hypothesized that adverse reactions might be linked with lysosomal dysfunction caused by nanomedicines. Finally, from our analysis it becomes clear that it is unjustifiable to generalize safety and toxicity of nanoparticles, since different particles possess distinct toxicological properties. We propose that the biological mechanism of the disease progression and treatment should be central in the optimization of nanoparticle design.


Asunto(s)
Nanomedicina , Nanopartículas , Humanos , Nanomedicina/métodos , Nanotecnología/métodos , Nanopartículas/toxicidad , Nanopartículas/química , Lisosomas
6.
ACS Biomater Sci Eng ; 9(5): 2408-2425, 2023 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-37001010

RESUMEN

It has become evident that physical stimuli of the cellular microenvironment transmit mechanical cues regulating key cellular functions, such as proliferation, migration, and malignant transformation. Accumulating evidence suggests that tumor cells face variable mechanical stimuli that may induce metabolic rewiring of tumor cells. However, the knowledge of how tumor cells adapt metabolism to external mechanical cues is still limited. We therefore designed soft 3D collagen scaffolds mimicking a pathological mechanical environment to decipher how liver tumor cells would adapt their metabolic activity to physical stimuli of the cellular microenvironment. Here, we report that the soft 3D microenvironment upregulates the glycolysis of HepG2 and Alexander cells. Both cell lines adapt their mitochondrial activity and function under growth in the soft 3D microenvironment. Cells grown in the soft 3D microenvironment exhibit marked mitochondrial depolarization, downregulation of mitochondrially encoded cytochrome c oxidase I, and slow proliferation rate in comparison with stiff monolayer cultures. Our data reveal the coupling of liver tumor glycolysis to mechanical cues. It is proposed here that soft 3D collagen scaffolds can serve as a useful model for future studies of mechanically regulated cellular functions of various liver (potentially other tissues as well) tumor cells.


Asunto(s)
Neoplasias Hepáticas , Microambiente Tumoral , Humanos , Dinámicas Mitocondriales , Colágeno
7.
Acta Biomater ; 146: 10-22, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35523414

RESUMEN

DNA nanotechnology has yielded remarkable advances in  composite materials with diverse applications in biomedicine. The specificity and predictability of building 3D structures at the nanometer scale make DNA nanotechnology a promising tool for uses in biosensing, drug delivery, cell modulation, and bioimaging. However, for successful translation of DNA nanostructures to real-world applications, it is crucial to understand how they interact with living cells, and the consequences of such interactions. In this review, we summarize the current state of knowledge on the interactions of DNA nanostructures with cells. We identify key challenges, from a cell biology perspective, that influence progress towards the clinical translation of DNA nanostructures. We close by providing an outlook on what questions must be addressed to accelerate the clinical translation of DNA nanostructures. STATEMENT OF SIGNIFICANCE: Self-assembled DNA nanostructures (DNs) offers unique opportunities to overcome persistent challenges in the nanobiotechnology field. However, the interactions between engineered DNs and living cells are still not well defined. Critical systematization of current cellular models and biological responses triggered by DNs is a crucial foundation for the successful clinical translation of DNA nanostructures. Moreover, such an analysis will identify the pitfalls and challenges that are present in the field, and provide a basis for overcoming those challenges.


Asunto(s)
Nanoestructuras , ADN/química , Sistemas de Liberación de Medicamentos/métodos , Nanoestructuras/química , Nanotecnología/métodos
8.
ACS Appl Mater Interfaces ; 13(39): 46375-46390, 2021 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-34569777

RESUMEN

DNA nanostructures (DNs) can be designed in a controlled and programmable manner, and these structures are increasingly used in a variety of biomedical applications, such as the delivery of therapeutic agents. When exposed to biological liquids, most nanomaterials become covered by a protein corona, which in turn modulates their cellular uptake and the biological response they elicit. However, the interplay between living cells and designed DNs are still not well established. Namely, there are very limited studies that assess protein corona impact on DN biological activity. Here, we analyzed the uptake of functionalized DNs in three distinct hepatic cell lines. Our analysis indicates that cellular uptake is linearly dependent on the cell size. Further, we show that the protein corona determines the endolysosomal vesicle escape efficiency of DNs coated with an endosome escape peptide. Our study offers an important basis for future optimization of DNs as delivery systems for various biomedical applications.


Asunto(s)
ADN/metabolismo , Endosomas/metabolismo , Nanoestructuras/química , Corona de Proteínas/metabolismo , Adsorción , Péptidos Catiónicos Antimicrobianos/química , Péptidos Catiónicos Antimicrobianos/metabolismo , Línea Celular Tumoral , ADN/química , Humanos , Lisosomas/metabolismo , Conformación de Ácido Nucleico , Corona de Proteínas/química
9.
Front Physiol ; 12: 693702, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34456745

RESUMEN

Oral treatment of apolipoprotein E-knockout (ApoE-KO) mice with the putative sirtuin 1 (SIRT1) activator resveratrol led to a reduction of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity in the heart. In contrast, the SIRT1 inhibitor EX527 enhanced the superoxide production in isolated human polymorphonuclear granulocytes. In human monocytic THP-1 cells, phorbol ester-stimulated superoxide production was enhanced by inhibitors of histone deacetylases (HDACs; including quisinostat, trichostatin A (TSA), PCI34051, and tubastatin A) and decreased by inhibitors of histone acetyltransferases [such as garcinol, curcumin, and histone acetyltransferase (HAT) Inhibitor II]. These results indicate that protein acetylation and deacetylation may represent crucial mechanisms regulating NADPH oxidase-mediated superoxide production. In cell-free systems, incubation of recombinant Rac1 with SIRT1 resulted in decreased Rac1 acetylation. Mass spectrometry analyses identified lysine 166 (K166) in Rac1 as a residue targeted by SIRT1. Deacetylation of Rac1 by SIRT1 markedly reduced the interaction of Rac1 with p67phox in in vitro assays. Computational modeling analyses revealed that K166 deacetylation of Rac1 led to a 5-fold reduction in its binding affinity to guanosine-5'-triphosphate, and a 21-fold decrease in its binding potential to p67phox. The latter is crucial for Rac1-mediated recruitment of p67phox to the membrane and for p67phox activation. In conclusion, both SIRT1 and non-sirtuin deacetylases play a role in regulating NADPH oxidase activity. Rac1 can be directly deacetylated by SIRT1 in a cell-free system, leading to an inhibition of Rac1-p67phox interaction. The downstream targets of non-sirtuin deacetylases are still unknown. The in vivo significance of these findings needs to be investigated in future studies.

10.
J Hepatol ; 75(4): 935-959, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34171436

RESUMEN

Drug-induced liver injury (DILI) is a major cause of acute liver failure (ALF) and one of the leading indications for liver transplantation in Western societies. Given the wide use of both prescribed and over the counter drugs, DILI has become a major health issue for which there is a pressing need to find novel and effective therapies. Although significant progress has been made in understanding the molecular mechanisms underlying DILI, our incomplete knowledge of its pathogenesis and inability to predict DILI is largely due to both discordance between human and animal DILI in preclinical drug development and a lack of models that faithfully recapitulate complex pathophysiological features of human DILI. This is exemplified by the hepatotoxicity of acetaminophen (APAP) overdose, a major cause of ALF because of its extensive worldwide use as an analgesic. Despite intensive efforts utilising current animal and in vitro models, the mechanisms involved in the hepatotoxicity of APAP are still not fully understood. In this expert Consensus Statement, which is endorsed by the European Drug-Induced Liver Injury Network, we aim to facilitate and outline clinically impactful discoveries by detailing the requirements for more realistic human-based systems to assess hepatotoxicity and guide future drug safety testing. We present novel insights and discuss major players in APAP pathophysiology, and describe emerging in vitro and in vivo pre-clinical models, as well as advanced imaging and in silico technologies, which may improve prediction of clinical outcomes of DILI.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Consenso , Acetaminofén/efectos adversos , Enfermedad Hepática Inducida por Sustancias y Drogas/fisiopatología , Europa (Continente) , Humanos , Hígado/efectos de los fármacos
11.
Front Med (Lausanne) ; 8: 574047, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34026769

RESUMEN

Liver cell types derived from induced pluripotent stem cells (iPSCs) share the potential to investigate development, toxicity, as well as genetic and infectious disease in ways currently limited by the availability of primary tissue. With the added advantage of patient specificity, which can play a role in all of these areas. Many iPSC differentiation protocols focus on 3 dimensional (3D) or organotypic differentiation, as these offer the advantage of more closely mimicking in vivo systems including; the formation of tissue like architecture and interactions/crosstalk between different cell types. Ultimately such models have the potential to be used clinically and either with or more aptly, in place of animal models. Along with the development of organotypic and micro-tissue models, there will be a need to co-develop imaging technologies to enable their visualization. A variety of liver models termed "organoids" have been reported in the literature ranging from simple spheres or cysts of a single cell type, usually hepatocytes, to those containing multiple cell types combined during the differentiation process such as hepatic stellate cells, endothelial cells, and mesenchymal cells, often leading to an improved hepatic phenotype. These allow specific functions or readouts to be examined such as drug metabolism, protein secretion or an improved phenotype, but because of their relative simplicity they lack the flexibility and general applicability of ex vivo tissue culture. In the liver field these are more often constructed rather than developed together organotypically as seen in other organoid models such as brain, kidney, lung and intestine. Having access to organotypic liver like surrogates containing multiple cell types with in vivo like interactions/architecture, would provide vastly improved models for disease, toxicity and drug development, combining disciplines such as microfluidic chip technology with organoids and ultimately paving the way to new therapies.

12.
Int J Mol Sci ; 22(5)2021 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-33806448

RESUMEN

Lambda interferons mediate antiviral immunity by inducing interferon-stimulated genes (ISGs) in epithelial tissues. A common variant rs368234815TT/∆G creating functional gene from an IFNL4 pseudogene is associated with the expression of major ISGs in the liver but impaired clearance of hepatitis C. To explain this, we compared Halo-tagged and non-tagged IFNL3 and IFNL4 signaling in liver-derived cell lines. Transfection with non-tagged IFNL3, non-tagged IFNL4 and Halo-tagged IFNL4 led to a similar degree of JAK-STAT activation and ISG induction; however, the response to transfection with Halo-tagged IFNL3 was lower and delayed. Transfection with non-tagged IFNL3 or IFNL4 induced no transcriptome change in the cells lacking either IL10R2 or IFNLR1 receptor subunits. Cytosolic overexpression of signal peptide-lacking IFNL3 or IFNL4 in wild type cells did not interfere with JAK-STAT signaling triggered by interferons in the medium. Finally, expression profile changes induced by transfection with non-tagged IFNL3 and IFNL4 were highly similar. These data do not support the hypothesis about IFNL4-specific non-canonical signaling and point out that functional studies conducted with tagged interferons should be interpreted with caution.


Asunto(s)
Hepatocitos/inmunología , Hepatocitos/metabolismo , Interferones/genética , Interferones/metabolismo , Interleucinas/genética , Interleucinas/metabolismo , Línea Celular , Expresión Génica , Técnicas de Inactivación de Genes , Células Hep G2 , Humanos , Factores Reguladores del Interferón/genética , Factores Reguladores del Interferón/metabolismo , Interferones/deficiencia , Subunidad beta del Receptor de Interleucina-10/deficiencia , Subunidad beta del Receptor de Interleucina-10/genética , Subunidad beta del Receptor de Interleucina-10/metabolismo , Interleucinas/deficiencia , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores de Interferón/deficiencia , Receptores de Interferón/genética , Receptores de Interferón/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transducción de Señal , Transfección
13.
Eur J Clin Invest ; 51(7): e13539, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33729579

RESUMEN

BACKGROUND: Gremlin-1 is a cystine knot protein and is expressed in organs developing fibrosis. Transient ischaemia leads to myocardial fibrosis, a major determinant of impaired myocardial function. MATERIALS AND METHODS: Expression of Gremlin-1 was investigated in infarcted myocardium by real-time PCR, Western blot analysis, histological and immunohistochemistry staining. We further elaborated the colocalization of Gremlin-1 and TGF-ß proteins by confocal microscopy and co-immunoprecipitation experiments. The interaction between Gremlin-1 and TGF-ß was analysed by photon correlation spectroscopy. Gremlin-1 modulation of the TGF-ß-dependent collagen I synthesis in fibroblasts was investigated using ELISA and immunohistochemistry experiments. The effect of prolonged administration of recombinant Gremlin-1 on myocardial function following ischaemia/reperfusion was accessed by echocardiography and immunohistochemistry. RESULTS: Gremlin-1 is expressed in myocardial tissue and infiltrating cells after transient myocardial ischaemia (P < .05). Gremlin-1 colocalizes with the pro-fibrotic cytokine transforming growth factor-ß (TGF-ß) expressed in fibroblasts and inflammatory cell infiltrates (P < .05). Gremlin-1 reduces TGF-ß-induced collagen production of myocardial fibroblasts by approximately 20% (P < .05). We found that Gremlin-1 binds with high affinity to TGF-ß (KD  = 54 nmol/L) as evidenced by photon correlation spectroscopy and co-immunoprecipitation. intravenous administration of m Gremlin-1-Fc, but not of equivalent amount of Fc control, significantly reduced infarct size by approximately 20%. In the m Gremlin-1-Fc group, infarct area was reduced by up to 30% in comparison with mice treated with Fc control (I/LV: 4.8 ± 1.2% vs 6.0 ± 1.2% P < .05; I/AaR: 15.2 ± 1.5% vs 21.1 ± 5%, P < .05). CONCLUSIONS: The present data disclose Gremlin-1 as an antagonist of TGF-ß and presume a role for Gremlin-1/TGF-ß interaction in myocardial remodelling following myocardial ischaemia.


Asunto(s)
Fibroblastos/metabolismo , Corazón/fisiopatología , Péptidos y Proteínas de Señalización Intercelular/genética , Infarto del Miocardio/genética , Daño por Reperfusión Miocárdica/genética , Miocardio/patología , Factor de Crecimiento Transformador beta/metabolismo , Animales , Colágeno Tipo I/metabolismo , Ecocardiografía , Células Endoteliales/metabolismo , Fibroblastos/efectos de los fármacos , Fibrosis , Corazón/diagnóstico por imagen , Corazón/efectos de los fármacos , Humanos , Inmunoprecipitación , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Péptidos y Proteínas de Señalización Intercelular/farmacología , Ratones , Microscopía Confocal , Infarto del Miocardio/metabolismo , Infarto del Miocardio/patología , Infarto del Miocardio/fisiopatología , Daño por Reperfusión Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/patología , Daño por Reperfusión Miocárdica/fisiopatología , Proteínas Recombinantes , Factor de Crecimiento Transformador beta/efectos de los fármacos , Remodelación Ventricular/genética
14.
Pharmaceuticals (Basel) ; 13(12)2020 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-33260691

RESUMEN

Recent studies undoubtedly show that the mammalian target of rapamycin (mTOR) and the Hippo-Yes-associated protein 1 (YAP) pathways are important mediators of mechanical cues. The crosstalk between these pathways as well as de-regulation of their signaling has been implicated in multiple tumor types, including liver tumors. Additionally, physical cues from 3D microenvironments have been identified to alter gene expression and differentiation of different cell lineages. However, it remains incompletely understood how physical constraints originated in 3D cultures affect cell plasticity and what the key mediators are of such process. In this work, we use collagen scaffolds as a model of a soft 3D microenvironment to alter cellular size and study the mechanotransduction that regulates that process. We show that the YAP-mTOR axis is a downstream effector of 3D cellular culture-driven mechanotransduction. Indeed, we found that cell mechanics, dictated by the physical constraints of 3D collagen scaffolds, profoundly affect cellular proliferation in a YAP-mTOR-mediated manner. Functionally, the YAP-mTOR connection is key to mediate cell plasticity in hepatic tumor cell lines. These findings expand the role of YAP-mTOR-driven mechanotransduction to the control hepatic tumor cellular responses under physical constraints in 3D cultures. We suggest a tentative mechanism, which coordinates signaling rewiring with cytoplasmic restructuring during cell growth in 3D microenvironments.

15.
Int J Mol Sci ; 21(17)2020 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-32872159

RESUMEN

The emerged field of non-thermal plasma (NTP) shows great potential in the alteration of cell redox status, which can be utilized as a promising therapeutic implication. In recent years, the NTP field considerably progresses in the modulation of immune cell function leading to promising in vivo results. In fact, understanding the underlying cellular mechanisms triggered by NTP remains incomplete. In order to boost the field closer to real-life clinical applications, there is a need for a critical overview of the current state-of-the-art. In this review, we conduct a critical analysis of the NTP-triggered modulation of immune cells. Importantly, we analyze pitfalls in the field and identify persisting challenges. We show that the identification of misconceptions opens a door to the development of a research strategy to overcome these limitations. Finally, we propose the idea that solving problems highlighted in this review will accelerate the clinical translation of NTP-based treatments.


Asunto(s)
Inmunidad Celular/efectos de los fármacos , Gases em Plasma/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Transducción de Señal/efectos de los fármacos
16.
Nanomaterials (Basel) ; 10(9)2020 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-32825748

RESUMEN

Heterodimeric nanoparticles comprising materials with different functionalities are of great interest for fundamental research and biomedical/industrial applications. In this work, Fe3O4-Au nano-heterostructures were synthesized by a one-step thermal decomposition method. The hybrid nanoparticles comprise a highly crystalline 12 nm magnetite octahedron decorated with a single noble metal sphere of 6 nm diameter. Detailed analysis of the nanoparticles was performed by UV-visible spectroscopy, magnetometry, calorimetry and relaxometry studies. The cytotoxic effect of the nanoparticles in the human hepatic cell line Huh7 and PLC/PRF/5-Alexander was also assessed. These Fe3O4-Au bifunctional nanoparticles showed no significant cytotoxicity in these two cell lines. The nanoparticles showed a good theranostic potential for liver cancer treatment, since the r2 relaxivity (166.5 mM-1·s-1 and 99.5 mM-1·s-1 in water and HepG2 cells, respectively) is higher than the corresponding values for commercial T2 contrast agents and the Specific Absorption Rate (SAR) value obtained (227 W/gFe) is enough to make them suitable as heat mediators for Magnetic Fluid Hyperthermia. The gold counterpart can further allow the conjugation with different biomolecules and the optical sensing.

17.
J Control Release ; 328: 59-77, 2020 12 10.
Artículo en Inglés | MEDLINE | ID: mdl-32860925

RESUMEN

Iron oxide nanoparticles (IONPs) were the first generation of nanomaterials that reached real clinic use. Particularly, several IONPs-based magnetic resonance imaging contrast agents gained approval by US Food and Drug Administration (FDA). However, latter body of evidence revealed the overlooked side effects of IONPs, resulting in their withdrawal. Emerging evidence suggests that this happened due to poor understanding of the mechanisms by which IONPs act at the cellular and sub-cellular levels. Recent studies indicate that better understanding of fundamental signal modulations induced by nanomaterials is essential to overcome the clinical problems with nanoparticles. Therefore, in this article we critically review potential mechanisms of IONPs-cell interactions and challenges related with their identification. We describe mechanisms of IONPs-induced toxicity. Ultimately, we demonstrate that knowledge of cellular mechanisms of IONPs action helped to overcome certain translation problems in nanomedicine - we explore potential causes and challenges associated with poor clinical performance of IONPs and propose outlook of how to overcome problems in the field. Our critical analysis implies that a clear understanding of molecular mechanisms of IONPs-cell interactions will provide a basement to increase the likelihood for clinical success of IONPs.


Asunto(s)
Nanopartículas de Magnetita , Nanopartículas , Medios de Contraste , Compuestos Férricos , Nanopartículas Magnéticas de Óxido de Hierro , Imagen por Resonancia Magnética
18.
Nano Converg ; 7(1): 17, 2020 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-32424769

RESUMEN

Iron oxide nanoparticles (IONs) are frequently used in various biomedical applications, in particular as magnetic resonance imaging contrast agents in liver imaging. Indeed, number of IONs have been withdrawn due to their poor clinical performance. Yet comprehensive understanding of their interactions with hepatocytes remains relatively limited. Here we investigated how iron oxide nanocubes (IO-cubes) and clusters of nanocubes (IO-clusters) affect distinct human hepatic cell lines. The viability of HepG2, Huh7 and Alexander cells was concentration-dependently decreased after exposure to either IO-cubes or IO-clusters. We found similar cytotoxicity levels in three cell lines triggered by both nanoparticle formulations. Our data indicate that different expression levels of Bcl-2 predispose cell death signaling mediated by nanoparticles. Both nanoparticles induced rather apoptosis than autophagy in HepG2. Contrary, IO-cubes and IO-clusters trigger distinct cell death signaling events in Alexander and Huh7 cells. Our data clarifies the mechanism by which cubic nanoparticles induce autophagic flux and the mechanism of subsequent toxicity. These findings imply that the cytotoxicity of ION-based contrast agents should be carefully considered, particularly in patients with liver diseases.

19.
Cells ; 9(4)2020 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-32325714

RESUMEN

Iron oxide-based nanoparticles have been repeatedly shown to affect lysosomal-mediated signaling. Recently, nanoparticles have demonstrated an ability to modulate autophagic flux via lysosome-dependent signaling. However, the precise underlying mechanisms of such modulation as well as the impact of cellular genetic background remain enigmatic. In this study, we investigated how lysosomal-mediated signaling is affected by iron oxide nanoparticle uptake in three distinct hepatic cell lines. We found that nanoparticle-induced lysosomal dysfunction alters sub-cellular localization of pmTOR and p53 proteins. Our data indicate that alterations in the sub-cellular localization of p53 protein induced by nanoparticle greatly affect the autophagic flux. We found that cells with high levels of Bcl-2 are insensitive to autophagy initiated by nanoparticles. Altogether, our data identify lysosomes as a central hub that control nanoparticle-mediated responses in hepatic cells. Our results provide an important fundamental background for the future development of targeted nanoparticle-based therapies.


Asunto(s)
Hepatocitos/metabolismo , Lisosomas/metabolismo , Nanopartículas Magnéticas de Óxido de Hierro , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Autofagia/genética , Línea Celular , Humanos , Serina-Treonina Quinasas TOR/metabolismo
20.
Macromol Biosci ; 20(3): e1900351, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32045093

RESUMEN

Ultra-low fouling and functionalizable coatings represent emerging surface platforms for various analytical and biomedical applications such as those involving examination of cellular interactions in their native environments. Ultra-low fouling surface platforms as advanced interfaces enabling modulation of behavior of living cells via tuning surface physicochemical properties are presented and studied. The state-of-art ultra-low fouling surface-grafted polymer brushes of zwitterionic poly(carboxybetaine acrylamide), nonionic poly(N-(2-hydroxypropyl)methacrylamide), and random copolymers of carboxybetaine methacrylamide (CBMAA) and HPMAA [p(CBMAA-co-HPMAA)] with tunable molar contents of CBMAA and HPMAA are employed. Using a model Huh7 cell line, a systematic study of surface wettability, swelling, and charge effects on the cell growth, shape, and cytoskeleton distribution is performed. This study reveals that ultra-low fouling interfaces with a high content of zwitterionic moieties (>65 mol%) modulate cell behavior in a distinctly different way compared to coatings with a high content of nonionic HPMAA. These differences are attributed mostly to the surface hydration capabilities. The results demonstrate a high potential of carboxybetaine-rich ultra-low fouling surfaces with high hydration capabilities and minimum background signal interferences to create next-generation bioresponsive interfaces for advanced studies of living objects.


Asunto(s)
Materiales Biocompatibles Revestidos , Citoesqueleto/metabolismo , Ensayo de Materiales , Polímeros , Línea Celular Tumoral , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Humanos , Polímeros/química , Polímeros/farmacología , Humectabilidad
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