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1.
Chem Eng J ; 4982024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39372137

RESUMO

DNA nanotechnology is a rapidly growing field that provides exciting tools for biomedical applications. Targeting lysosomal functions with nanomaterials, such as DNA nanostructures (DNs), represents a rational and systematic way to control cell functionality. Here we present a versatile DNA nanostructure-based platform that can modulate a number of cellular functions depending on the concentration and surface decoration of the nanostructure. Utilizing different peptides for surface functionalization of DNs, we were able to rationally modulate lysosomal activity, which in turn translated into the control of cellular function, ranging from changes in cell morphology to modulation of immune signaling and cell death. Low concentrations of decalysine peptide-coated DNs induced lysosomal acidification, altering the metabolic activity of susceptible cells. In contrast, DNs coated with an aurein-bearing peptide promoted lysosomal alkalization, triggering STING activation. High concentrations of decalysine peptide-coated DNs caused lysosomal swelling, loss of cell-cell contacts, and morphological changes without inducing cell death. Conversely, high concentrations of aurein-coated DNs led to lysosomal rupture and mitochondrial damage, resulting in significant cytotoxicity. Our study holds promise for the rational design of a new generation of versatile DNA-based nanoplatforms that can be used in various biomedical applications, like the development of combinatorial anti-cancer platforms, efficient systems for endolysosomal escape, and nanoplatforms modulating lysosomal pH.

2.
Kidney Int ; 101(2): 349-359, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34560138

RESUMO

Amyloid A amyloidosis is a serious clinical condition resulting from the systemic deposition of amyloid A originating from serum amyloid A proteins with the kidneys being the most commonly and earliest affected organ. Previously described amyloid A amyloidosis is linked to increased production and deposition of serum amyloid A proteins secondary to inflammatory conditions arising from infectious, metabolic, or genetic causes. Here we describe a family with primary amyloid A amyloidosis due to a chr11:18287683 T>C (human genome version19) mutation in the SAA1 promoter linked to the amyloidogenic SAA1.1 haplotype. This condition leads to a doubling of the basal SAA1 promoter activity and sustained elevation of serum amyloid A levels that segregated in an autosomal dominant pattern in 12 genetically affected and in none of six genetically unaffected relatives, yielding a statistically significant logarithm of odds (LOD) score over 5. Affected individuals developed proteinuria, chronic kidney disease and systemic deposition of amyloid composed specifically of the SAA1.1 isoform. Tocilizumab (a monoclonal antibody against the interleukin-6 receptor) had a beneficial effect when prescribed early in the disease course. Idiopathic forms represent a significant and increasing proportion (15-20%) of all diagnosed cases of amyloid A amyloidosis. Thus, genetic screening of the SAA1 promoter should be pursued in individuals with amyloid A amyloidosis and no systemic inflammation, especially if there is a positive family history.


Assuntos
Amiloidose , Amiloidose/complicações , Humanos , Mutação , Regiões Promotoras Genéticas , Proteína Amiloide A Sérica/genética , Proteína Amiloide A Sérica/metabolismo
3.
Cell Mol Life Sci ; 77(14): 2815-2838, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31583425

RESUMO

Biological effects of high fluence low-power (HFLP) lasers have been reported for some time, yet the molecular mechanisms procuring cellular responses remain obscure. A better understanding of the effects of HFLP lasers on living cells will be instrumental for the development of new experimental and therapeutic strategies. Therefore, we investigated sub-cellular mechanisms involved in the laser interaction with human hepatic cell lines. We show that mitochondria serve as sub-cellular "sensor" and "effector" of laser light non-specific interactions with cells. We demonstrated that despite blue and red laser irradiation results in similar apoptotic death, cellular signaling and kinetic of biochemical responses are distinct. Based on our data, we concluded that blue laser irradiation inhibited cytochrome c oxidase activity in electron transport chain of mitochondria. Contrary, red laser triggered cytochrome c oxidase excessive activation. Moreover, we showed that Bcl-2 protein inhibited laser-induced toxicity by stabilizing mitochondria membrane potential. Thus, cells that either overexpress or have elevated levels of Bcl-2 are protected from laser-induced cytotoxicity. Our findings reveal the mechanism how HFLP laser irradiation interfere with cell homeostasis and underscore that such laser irradiation permits remote control of mitochondrial function in the absence of chemical or biological agents.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/genética , Transporte de Elétrons/efeitos da radiação , Terapia com Luz de Baixa Intensidade , Fototerapia , Apoptose/efeitos da radiação , Sobrevivência Celular/genética , Sobrevivência Celular/efeitos da radiação , Transporte de Elétrons/genética , Regulação da Expressão Gênica/efeitos da radiação , Células Hep G2 , Humanos , Potencial da Membrana Mitocondrial/genética , Potencial da Membrana Mitocondrial/efeitos da radiação , Mitocôndrias/genética , Mitocôndrias/efeitos da radiação , Membranas Mitocondriais/metabolismo , Membranas Mitocondriais/efeitos da radiação , Oxirredução/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo
4.
Int J Mol Sci ; 22(5)2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33806448

RESUMO

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.


Assuntos
Hepatócitos/imunologia , Hepatócitos/metabolismo , Interferons/genética , Interferons/metabolismo , Interleucinas/genética , Interleucinas/metabolismo , Linhagem Celular , Expressão Gênica , Técnicas de Inativação de Genes , Células Hep G2 , Humanos , Fatores Reguladores de Interferon/genética , Fatores Reguladores de Interferon/metabolismo , Interferons/deficiência , Subunidade beta de Receptor de Interleucina-10/deficiência , Subunidade beta de Receptor de Interleucina-10/genética , Subunidade beta de Receptor de Interleucina-10/metabolismo , Interleucinas/deficiência , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Interferon/deficiência , Receptores de Interferon/genética , Receptores de Interferon/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transdução de Sinais , Transfecção
5.
Int J Mol Sci ; 22(19)2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34638908

RESUMO

Heterozygotes for Z or S alleles of alpha-1-antrypsin (AAT) have low serum AAT levels. Our aim was to compare the risk of hepatocellular carcinoma (HCC) in patients with liver cirrhosis carrying the SERPINA1 MM, MZ and MS genotypes. The study groups consisted of 1119 patients with liver cirrhosis of various aetiologies, and 3240 healthy individuals served as population controls. The MZ genotype was significantly more frequent in the study group (55/1119 vs. 87/3240, p < 0.0001). The MS genotype frequency was comparable in controls (32/119 vs. 101/3240, p = 0.84). MZ and MS heterozygotes had lower serum AAT level than MM homozygotes (medians: 0.90 g/L; 1.40 g/L and 1.67 g/L; p < 0.001 for both). There were significantly fewer patients with HCC in the cirrhosis group among MZ and MS heterozygotes than in MM homozygotes (5/55 and 1/32 respectively, vs. 243/1022, p < 0.01 for both). The risk of HCC was lower in MZ and MS heterozygotes than in MM homozygotes (OR 0.3202; 95% CI 0.1361-0.7719 and OR 0.1522; 95% CI 0.02941-0.7882, respectively). Multivariate analysis of HCC risk factors identified MZ or MS genotype carriage as a protective factor, whereas age, male sex, BMI and viral aetiology of cirrhosis increased HCC risk.


Assuntos
Carcinoma Hepatocelular/genética , Cirrose Hepática/genética , Neoplasias Hepáticas/genética , alfa 1-Antitripsina/genética , Alelos , Índice de Massa Corporal , Carcinoma Hepatocelular/complicações , Feminino , Frequência do Gene , Genótipo , Humanos , Cirrose Hepática/complicações , Neoplasias Hepáticas/complicações , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fatores de Risco , Fatores Sexuais , alfa 1-Antitripsina/sangue
6.
Int J Mol Sci ; 21(17)2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32872159

RESUMO

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.


Assuntos
Imunidade Celular/efeitos dos fármacos , Gases em Plasma/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Transdução de Sinais/efeitos dos fármacos
7.
Cell Physiol Biochem ; 52(1): 119-140, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30790509

RESUMO

BACKGROUND/AIMS: Alteration of cancer cell redox status has been recognized as a promising therapeutic implication. In recent years, the emerged field of non-thermal plasma (NTP) has shown considerable promise in various biomedical applications, including cancer therapy. However, understanding the molecular mechanisms procuring cellular responses remains incomplete. Thus, the aim of this study was a rigorous biochemical analysis of interactions between NTP and liver cancer cells. METHODS: The concept was validated using three different cell lines. We provide several distinct lines of evidence to support our findings; we use various methods (epifluorescent and confocal microscopy, clonogenic and cytotoxicity assays, Western blotting, pharmacological inhibition studies, etc.). RESULTS: We assessed the influence of NTP on three human liver cancer cell lines (Huh7, Alexander and HepG2). NTP treatment resulted in higher anti-proliferative effect against Alexander and Huh7 relative to HepG2. Our data clearly showed that the NTP-mediated alternation of mitochondrial membrane potential and dynamics led to ROS-mediated apoptosis in Huh7 and Alexander cells. Interestingly, plasma treatment resulted in p53 down-regulation in Huh7 cells. High levels of Bcl-2 protein expression in HepG2 resulted in their resistance in response to oxidative stress- mediated by plasma. CONCLUSION: We show thoroughly time- and dose-dependent kinetics of ROS accumulation in HCC cells. Furthermore, we show nuclear compartmentalization of the superoxide anion triggered by NTP. NTP induced apoptotic death in Huh7 liver cancer cells via simultaneous downregulation of mutated p53, pSTAT1 and STAT1. Contrary, hydrogen peroxide treatment results in autophagic cell death. We disclosed detailed mechanisms of NTP-mediated alteration of redox signalling in liver cancer cells.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Gases em Plasma/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Proteína Supressora de Tumor p53/biossíntese , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Morte Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Oxirredução/efeitos dos fármacos , Proteína Supressora de Tumor p53/genética
8.
J Pathol ; 241(1): 104-114, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27741349

RESUMO

Iron is both an essential and a potentially toxic element, and its systemic homeostasis is controlled by the iron hormone hepcidin. Hepcidin binds to the cellular iron exporter ferroportin, causes its degradation, and thereby diminishes iron uptake from the intestine and the release of iron from macrophages. Given that hepcidin-resistant ferroportin mutant mice show exocrine pancreas dysfunction, we analysed pancreata of aging hepcidin knockout (KO) mice. Hepcidin and Hfe KO mice were compared with wild-type (WT) mice kept on standard or iron-rich diets. Twelve-month-old hepcidin KO mice were subjected to daily minihepcidin PR73 treatment for 1 week. Six-month-old hepcidin KO mice showed cytoplasmic acinar iron overload and mild pancreatitis, together with elevated expression of the iron uptake mediators DMT1 and Zip14. Acinar atrophy, massive macrophage infiltration, fatty changes and pancreas fibrosis were noted in 1-year-old hepcidin KO mice. As an underlying mechanism, 6-month-old hepcidin KO mice showed increased pancreatic oxidative stress, with elevated DNA damage, apoptosis and activated nuclear factor-κB (NF-κB) signalling. Neither iron overload nor pancreatic damage was observed in WT mice fed iron-rich diet or in Hfe KO mice. Minihepcidin application to hepcidin KO mice led to an improvement in general health status and to iron redistribution from acinar cells to macrophages. It also resulted in decreased NF-κB activation and reduced DNA damage. In conclusion, loss of hepcidin signalling in mice leads to iron overload-induced chronic pancreatitis that is not seen in situations with less severe iron accumulation. The observed tissue injury can be reversed by hepcidin supplementation. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Células Acinares/metabolismo , Hepcidinas/deficiência , Sobrecarga de Ferro/complicações , Pancreatite Crônica/etiologia , Animais , Apoptose/fisiologia , Citoplasma/metabolismo , Modelos Animais de Doenças , Hepcidinas/genética , Hepcidinas/fisiologia , Sobrecarga de Ferro/metabolismo , Sobrecarga de Ferro/patologia , Macrófagos/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Estresse Oxidativo/fisiologia , Pâncreas/ultraestrutura , Pancreatite Crônica/metabolismo , Pancreatite Crônica/patologia
9.
J Hepatol ; 61(3): 633-41, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24816174

RESUMO

BACKGROUND & AIMS: Hepcidin is the central regulator of iron homeostasis and altered hepcidin signalling results in both hereditary and acquired iron overload. While the association between iron overload and development of end-stage liver disease is well established, the underlying mechanisms are largely unknown. To improve that, we analysed hepcidin knockout (KO) mice as a model of iron overload-associated liver disease. METHODS: Hepcidin wild type (WT) and KO mice fed with 3% carbonyl iron-containing diet starting at one month of age were compared to age-matched animals kept on standard chow. Liver histology and serum parameters were used to assess the extent of liver injury and fibrosis. Iron distribution was determined by subcellular fractionation and electron microscopy. RESULTS: Among mice kept on iron-rich diet, 6 months old hepcidin KO mice (vs. WT) displayed profound hepatic iron overload (3,186 ± 411 vs. 1,045 ± 159 µg/mg tissue, p<0.005), elevated liver enzymes (ALT: KO 128 ± 6, WT 56 ± 5 IU/L, p<0.05), mild hepatic inflammation and hepatocellular apoptosis. Twelve, but not six months old KO mice fed with iron-rich diet developed moderate liver fibrosis. The liver injury was accompanied by a marked lysosomal iron overload and lysosomal fragility with release of cathepsin B into the cytoplasm. Increased p62 levels and autofluorescent iron complexes suggested impaired protein degradation. As a mechanism leading to lysosomal iron overload, the autophagy (lysosomal influx) was increased. CONCLUSIONS: Hepcidin KO mice represent a novel model of iron overload-related liver diseases and implicate lysosomal injury as a crucial event in iron toxicity.


Assuntos
Hepcidinas/deficiência , Ferro da Dieta/efeitos adversos , Ferro/metabolismo , Cirrose Hepática/etiologia , Lesão Pulmonar/etiologia , Lisossomos/metabolismo , Animais , Apoptose/fisiologia , Modelos Animais de Doenças , Células Estreladas do Fígado/patologia , Células Estreladas do Fígado/fisiologia , Hepcidinas/genética , Hepcidinas/fisiologia , Homeostase/fisiologia , Fígado/enzimologia , Fígado/patologia , Cirrose Hepática/metabolismo , Cirrose Hepática/fisiopatologia , Lesão Pulmonar/metabolismo , Lesão Pulmonar/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fatores de Tempo
10.
Biomater Biosyst ; 14: 100093, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38585282

RESUMO

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.

11.
Discov Nano ; 19(1): 106, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38907808

RESUMO

In recent years, it has been recognized that mechanical forces play an important regulative role in living organisms and possess a direct impact on crucial cell functions, ranging from cell growth to maintenance of tissue homeostasis. Advancements in mechanobiology have revealed the profound impact of mechanical signals on diverse cellular responses that are cell type specific. Notably, numerous studies have elucidated the pivotal role of different mechanical cues as regulatory factors influencing various cellular processes, including cell spreading, locomotion, differentiation, and proliferation. Given these insights, it is unsurprising that the responses of cells regulated by physical forces are intricately linked to the modulation of nanoparticle uptake kinetics and processing. This complex interplay underscores the significance of understanding the mechanical microenvironment in shaping cellular behaviors and, consequently, influencing how cells interact with and process nanoparticles. Nevertheless, our knowledge on how localized physical forces affect the internalization and processing of nanoparticles by cells remains rather limited. A significant gap exists in the literature concerning a systematic analysis of how mechanical cues might bias the interactions between nanoparticles and cells. Hence, our aim in this review is to provide a comprehensive and critical analysis of the existing knowledge regarding the influence of mechanical cues on the complicated dynamics of cell-nanoparticle interactions. By addressing this gap, we would like to contribute to a detailed understanding of the role that mechanical forces play in shaping the complex interplay between cells and nanoparticles.

12.
Nanoscale Adv ; 5(16): 4250-4268, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37560414

RESUMO

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.

13.
ACS Biomater Sci Eng ; 9(5): 2408-2425, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-37001010

RESUMO

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.


Assuntos
Neoplasias Hepáticas , Microambiente Tumoral , Humanos , Dinâmica Mitocondrial , Colágeno
14.
Adv Drug Deliv Rev ; 197: 114828, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37075952

RESUMO

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.


Assuntos
Nanomedicina , Nanopartículas , Humanos , Nanomedicina/métodos , Nanotecnologia/métodos , Nanopartículas/toxicidade , Nanopartículas/química , Lisossomos
15.
Sci Rep ; 13(1): 10818, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37402779

RESUMO

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.


Assuntos
Campos Eletromagnéticos , Campos Magnéticos , Humanos , Células HeLa
16.
BMC Gastroenterol ; 12: 147, 2012 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-23078008

RESUMO

BACKGROUND: Keratins 8/18 (K8/K18) are established hepatoprotective proteins and K8/K18 variants predispose to development and adverse outcome of multiple liver disorders. The importance of K8/K18 in alcoholic liver disease as well as in established cirrhosis remains unknown. METHODS: We analyzed the K8 mutational hot-spots in 261 prospectively followed-up patients with alcoholic cirrhosis (mean follow-up 65 months). PCR-amplified samples were pre-screened by denaturing high-performance liquid chromatography and conspicuous samples were sequenced. RESULTS: 67 patients developed hepatocellular carcinoma (HCC) and 133 died. Fourteen patients harbored amino-acid-altering K8 variants (5xG62C, 8xR341H). The presence of K8 variants did not associate with development of HCC (log-rank=0.5) or death (log-rank=0.7) and no significant associations were obtained for the single K8 variants after a correction for multiple testing was performed. CONCLUSIONS: Keratin variants are expressed in a low percentage of patients with alcoholic cirrhosis and do not influence HCC development. Further studies conducted in larger prospective cohorts are needed to find out whether presence of K8 R341H variant predispose to non-HCC-related liver mortality.


Assuntos
Carcinoma Hepatocelular/genética , Queratina-8/genética , Cirrose Hepática Alcoólica/genética , Neoplasias Hepáticas/genética , Distribuição de Qui-Quadrado , Análise Mutacional de DNA , Éxons , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Mutação , Modelos de Riscos Proporcionais , Estudos Prospectivos , Estatísticas não Paramétricas
17.
Acta Biomater ; 146: 10-22, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35523414

RESUMO

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.


Assuntos
Nanoestruturas , DNA/química , Sistemas de Liberação de Medicamentos/métodos , Nanoestruturas/química , Nanotecnologia/métodos
18.
ACS Appl Mater Interfaces ; 13(39): 46375-46390, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34569777

RESUMO

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.


Assuntos
DNA/metabolismo , Endossomos/metabolismo , Nanoestruturas/química , Coroa de Proteína/metabolismo , Adsorção , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/metabolismo , Linhagem Celular Tumoral , DNA/química , Humanos , Lisossomos/metabolismo , Conformação de Ácido Nucleico , Coroa de Proteína/química
19.
PLoS One ; 16(1): e0244934, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33411729

RESUMO

Liver stiffness is a reliable non-invasive predictor of Hepatic Venous Pressure Gradient (HVPG) above 10 mm Hg. However, it failed to predict higher thresholds of HVPG. Our aim was to investigate whether liver stiffness and selected previously published non-invasive blood biomarkers could predict higher HVPG thresholds in liver transplant candidates without ongoing alcohol use. One hundred and nine liver transplant candidates with liver cirrhosis of various aetiologies underwent direct HVPG measurement, liver stiffness measurement by 2D shear-wave elastography (Aixplorer Multiwave, Supersonic Imagine, France) and assessment of blood HVPG biomarkers (osteopontin, VCAM-1, IL-6, TNF-α, IL-1ra/IL-1F3 and ELF score). The correlation between liver stiffness and HVPG was linear up to 30 mm Hg of HVPG (r = 0.765, p < 0.0001). The regression lines had similar slopes for HVPG values below and above 16 mm Hg (p > 0.05) and the correlation in patients with HVPG <16 mm Hg (r = 0.456, p = 0.01) was similar to patients with HVPG ≥ 16 mm Hg (r = 0.499, p < 0.0001). The correlation was similar in the subgroup patients with alcoholic (r = 0.718, p < 0.0001), NASH (r = 0.740, p = 0.008), cryptogenic (r = 0.648, p = 0,0377), cholestatic and autoimmune (r = 0.706, p < 0.0001) and viral cirrhosis (r = 0.756, p < 0.0001). Liver stiffness distinguished patients with HVPG above 16, and 20 mm Hg with AUROCs 0.90243, and 0.86824, sensitivity 0.7656, and 0.7027, and specificity 0.9333, and 0.8750. All studied blood biomarkers correlated better with liver stiffness than with HVPG and their AUROCs did not exceed 0.8 at both HVPG thresholds. Therefore, a composite predictor superior to liver stiffness could not be established. We conclude that liver stiffness is a clinically reliable predictor of higher HVPG thresholds in non-drinking subjects with advanced liver cirrhosis.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Elasticidade/fisiologia , Fígado/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , República Tcheca , Feminino , Fibrose/patologia , Veias Hepáticas/patologia , Humanos , Hipertensão Portal/patologia , Modelos Lineares , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Pressão na Veia Porta/fisiologia , Estudos Prospectivos , Sensibilidade e Especificidade , Pressão Venosa/fisiologia
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