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1.
Colloids Surf B Biointerfaces ; 234: 113751, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38241889

RESUMO

Most of the malignancies detected within the brain parenchyma are of metastatic origin. As the brain lacks classical lymphatic circulation, the primary way for metastasis relies on hematogenous routes. Dissemination of metastatic cells to the brain implies attachment to the luminal surface of brain endothelial cells, transmigration through the vessel wall, and adhesion to the brain surface of the vasculature. During this process, tumor cells must interact with brain endothelial cells and later on with pericytes. Physical interaction between tumor cells and brain vascular cells might be crucial in the successful extravasation of metastatic cells through blood vessels and later in their survival within the brain environment. Therefore, we applied single-cell force spectroscopy to investigate the nanoscale adhesive properties of living breast adenocarcinoma cells to brain endothelial cells and pericytes. We found target cell type-dependent adhesion characteristics, i.e. increased adhesion of the tumor cells to pericytes in comparison to endothelial cells, which underlines the existence of metastatic potential-related nanomechanical differences relying partly on membrane tether dynamics. Varying adhesion strength of the tumor cells to different cell types of brain vessels presumably reflects the transitory adhesion to endothelial cells before extravasation and the long-lasting strong interaction with pericytes during survival and proliferation in the brain. Our results highlight the importance of specific mechanical interactions between tumor cells and host cells during metastasis formation.


Assuntos
Adenocarcinoma , Células Endoteliais , Humanos , Pericitos , Encéfalo/patologia , Endotélio , Adenocarcinoma/metabolismo
2.
Sci Rep ; 13(1): 18638, 2023 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-37903868

RESUMO

The purpose of the analysis was to identify the risk and protective factors for health behaviour in European adolescents from population health status and expenditure, mental health status, sexual life, social life and education indices and the existence of national strategies, programmes. National and international databases providing information on the presumed health behaviour predictors were used in the analysis. The existence of national health strategies, the level of health expenditure, the socioeconomic conditions, the level of education and literacy had significant influence on the health-risk behaviour of adolescents in the European societies. Six clusters of European countries were extracted by considering the health behaviour risks and health protection strategies. National health strategies combined with governmental support for health prevention and action plans have the most effective impact on the health-risk behaviour of adolescents.


Assuntos
Comportamentos Relacionados com a Saúde , Nível de Saúde , Humanos , Adolescente , Fatores de Proteção , Europa (Continente) , Escolaridade , Fatores de Risco
3.
Front Physiol ; 14: 1173636, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37664431

RESUMO

The interaction between the gut and brain is a great puzzle since it is mediated by very complex mechanisms. Therefore, the possible interactions of the brain-exercise-intestine-microbiome axis were investigated in a control (C, N = 6) and voluntarily exercised (VE, N = 8) middle-aged rats. The endurance capacity was assessed by VO2max on the treadmill, spatial memory by the Morris maze test, gastrointestinal motility by EMG, the microbiome by 16S RNA gene amplicon sequencing, caveolae by electron microscopy, and biochemical assays were used to measure protein levels and production of reactive oxygen species (ROS). Eight weeks of voluntary running increased VO2max, and spatial memory was assessed by the Morris maze test but did not significantly change the motility of the gastrointestinal tract or production of ROS in the intestine. The protein kinase B (Akt) and endothelial nitric oxide synthase (eNOS) protein levels significantly increased in the intestine, while peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α), mitochondrial transcription factor A (TFAM), nuclear respiratory factor 1 (NFR1), SIRT1, SIRT3, nicotinamide phosphoribosyl transferase (NAMPT), and nuclear factor κB (NF-κB) did not change. On the other hand, voluntary exercise increased the number of caveolae in the smooth muscles of the intestine and relative abundance of Bifidobacteria in the microbiome, which correlated with the Akt levels in the intestine. Voluntary exercise has systemic effects and the relationship between intestinal Akt and the microbiome of the gastrointestinal tract could be an important adaptive response.

4.
Acta Neuropathol Commun ; 11(1): 155, 2023 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-37749707

RESUMO

Inflammasomes, primarily responsible for the activation of IL-1ß, have emerged as critical regulators of the tumor microenvironment. By using in vivo and in vitro brain metastasis models, as well as human samples to study the role of the NLRP3 inflammasome in triple-negative breast cancer (TNBC) brain metastases, we found NLRP3 inflammasome components and IL-1ß to be highly and specifically expressed in peritumoral astrocytes. Soluble factors from TNBC cells induced upregulation and activation of NLRP3 and IL-1ß in astrocytes, while astrocyte-derived mediators augmented the proliferation of metastatic cells. In addition, inhibition of NLRP3 inflammasome activity using MCC950 or dampening the downstream effect of IL-1ß prevented the proliferation increase in cancer cells. In vivo, MCC950 reduced IL-1ß expression in peritumoral astrocytes, as well as the levels of inflammasome components and active IL-1ß. Most importantly, significantly retarded growth of brain metastatic tumors was observed in mice treated with MCC950. Overall, astrocytes contribute to TNBC progression in the brain through activation of the NLRP3 inflammasome and consequent IL-1ß release. We conclude that pharmacological targeting of inflammasomes may become a novel strategy in controlling brain metastatic diseases.


Assuntos
Neoplasias Encefálicas , Indenos , Neoplasias de Mama Triplo Negativas , Humanos , Animais , Camundongos , Inflamassomos , Astrócitos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Sulfonamidas/farmacologia , Microambiente Tumoral
5.
Sci Rep ; 13(1): 4155, 2023 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-36914729

RESUMO

Regular monitoring of children's nutritional status is essential to prevent micronutrient deficiencies, nutritional status abnormalities as stunting, wasting, overweight and obesity. Nutritional status assessment is usually performed by paediatricians by using anthropometry (body mass index, weight to height indices) and/or by body fat-mass measurement (bioimpedance analysis, dual-energy x-ray absorptiometry, computer tomography, etc.). Parents are also interested in but usually fail to evaluate their child's nutritional status. To help the sufficient collaboration between the physician and parents a new nutritional status monitoring method is developed for families. The new monitoring system was developed under a paediatrician's supervision by considering national and international recommendations, references as well as the anthropometric measurement possibilities at home. The model requires age, sex, body mass, height, waist circumference and hand circumference as predictor (input) variables of nutritional status, while (1) the centile values of the measured body dimensions, (2) body fat percentage and the centile of body fat percentage, (3) the nutritional status category (undernutrition, normal nutritional status, overfat/obese) can be predicted (outcome variables) by the new method. The predictive accuracy of the model for nutritional status category was 94.88% in boys and 98.66% in girls. The new model was developed for nutritional status assessment in school-aged children and will be incorporated in the healthy lifestyle module of 'Teenage Survival Guide' educational package to be developed by the Health Promotion and Education Research Team, Hungarian Academy of Sciences, Hungary. The new monitoring system could help the families to identify the early signs of malnutrition in children. Nutritional status assessment in children at home is suggested twice a year, and in case of suspicious nutritional status abnormality it is recommended to visit the general practitioner.


Assuntos
Desnutrição , Estado Nutricional , Masculino , Feminino , Adolescente , Humanos , Criança , Obesidade , Índice de Massa Corporal , Avaliação Nutricional , Antropometria
6.
ACS Appl Bio Mater ; 6(1): 64-73, 2023 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-36239448

RESUMO

Functionalized nanoparticles (NPs) are widely used in targeted drug delivery and biomedical imaging due to their penetration into living cells. The outer coating of most cells is a sugar-rich layer of the cellular glycocalyx, presumably playing an important part in any uptake processes. However, the exact role of the cellular glycocalyx in NP uptake is still uncovered. Here, we in situ monitored the cellular uptake of gold NPs─functionalized with positively charged alkaline thiol (TMA)─into adhered cancer cells with or without preliminary glycocalyx digestion. Proteoglycan (PG) components of the glycocalyx were treated by the chondroitinase ABC enzyme. It acts on chondroitin 4-sulfate, chondroitin 6-sulfate, and dermatan sulfate and slowly on hyaluronate. The uptake measurements of HeLa cells were performed by applying a high-throughput label-free optical biosensor based on resonant waveguide gratings. The positively charged gold NPs were used with different sizes [d = 2.6, 4.2, and 7.0 nm, small (S), medium (M), and large(L), respectively]. Negatively charged citrate-capped tannic acid (CTA, d = 5.5 nm) NPs were also used in control experiments. Real-time biosensor data confirmed the cellular uptake of the functionalized NPs, which was visually proved by transmission electron microscopy. It was found that the enzymatic digestion facilitated the entry of the positively charged S- and M-sized NPs, being more pronounced for the M-sized. Other enzymes digesting different components of the glycocalyx were also employed, and the results were compared. Glycosaminoglycan digesting heparinase III treatment also increased, while glycoprotein and glycolipid modifying neuraminidase decreased the NP uptake by HeLa cells. This suggests that the sialic acid residues increase, while heparan sulfate decreases the uptake of positively charged NPs. Our results raise the hypothesis that cellular uptake of 2-4 nm positively charged NPs is facilitated by glycoprotein and glycolipid components of the glycocalyx but inhibited by PGs.


Assuntos
Glicocálix , Nanopartículas Metálicas , Humanos , Ouro/química , Células HeLa , Nanopartículas Metálicas/química , Glicosaminoglicanos , Sulfatos de Condroitina
7.
Front Biosci (Landmark Ed) ; 27(9): 265, 2022 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-36224022

RESUMO

BACKGROUND: Earlier studies reported alterations of the kynurenine (KYN) pathway of tryptophan (TRP) metabolism in Parkinson's disease (PD). The first rate-limiting enzymes indoleamine 2,3-dioxygenase (IDO) and tryptophan dioxygenase were observed upregulated, resulting elevated KYN/TRP ratios in the serum and cerebrospinal fluid samples of patients with PD. More and more single nucleotide polymorphisms (SNPs) have been identified in a population of PD. However, little is known about the impact of genetic variations of the IDO on the pathogenesis of PD. METHODS: SNP analysis of IDO1 was performed by allelic discrimination assay with fluorescently labelled TaqMan probes and a subgroup analysis was conducted according to the age of PD onset. The frame shifts variant rs34155785, intronic variant rs7820268, and promotor region variant rs9657182 SNPs of 105 PD patients without comorbidity were analyzed and compared to 129 healthy controls. RESULTS: No significant correlation was found in three SNPs between PD patients and healthy controls. However, the subgroup analysis revealed that A alleles of rs7820268 SNP or rs9657182 SNP carriers contribute to later onset of PD than non-carriers. CONCLUSIONS: The study suggested that SNPs of IDO1 influenced the age onset of PD and genotyping of SNPs in certain alleles potentially serves as a risk biomarker of PD.


Assuntos
Indolamina-Pirrol 2,3,-Dioxigenase/genética , Cinurenina , Doença de Parkinson , Biomarcadores , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Cinurenina/genética , Cinurenina/metabolismo , Doença de Parkinson/genética , Polimorfismo de Nucleotídeo Único , Triptofano/genética , Triptofano/metabolismo
8.
Cancers (Basel) ; 14(16)2022 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-36010906

RESUMO

Nowadays, extracellular vesicles (EVs) raise a great interest as they are implicated in intercellular communication between cancer and stromal cells. Our aim was to understand how vesicular NME1 and NME2 released by breast cancer cells influence the tumour microenvironment. As a model, we used human invasive breast carcinoma cells overexpressing NME1 or NME2, and first analysed in detail the presence of both isoforms in EV subtypes by capillary Western immunoassay (WES) and immunoelectron microscopy. Data obtained by both methods showed that NME1 was present in medium-sized EVs or microvesicles, whereas NME2 was abundant in both microvesicles and small-sized EVs or exosomes. Next, human skin-derived fibroblasts were treated with NME1 or NME2 containing EVs, and subsequently mRNA expression changes in fibroblasts were examined. RNAseq results showed that the expression of fatty acid and cholesterol metabolism-related genes was decreased significantly in response to NME1 or NME2 containing EV treatment. We found that FASN (fatty acid synthase) and ACSS2 (acyl-coenzyme A synthetase short-chain family member 2), related to fatty acid synthesis and oxidation, were underexpressed in NME1/2-EV-treated fibroblasts. Our data show an emerging link between NME-containing EVs and regulation of tumour metabolism.

9.
PLoS One ; 17(4): e0266782, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35468161

RESUMO

INTRODUCTION: Beyond the three-dimensional fibrin network, the mechanical and lytic stability of thrombi is supported by the matrix of neutrophil extracellular traps (NETs) composed of polyanionic DNA meshwork with attached proteins including polycationic histones. Polyphosphates represent another type of polyanions, which in their linear form are known to enhance the fibrin stabilizing effects of DNA and histones. However, in vivo polyphosphates are also present in the form of nanoparticles (PolyP-NP), the interference of which with the fibrin/NET matrix is poorly characterized. AIMS: To compare the effects of linear and nanoparticulate polyphosphates, and their combinations with relevant NET components (DNA, histone H3) on fibrin formation, structure, and lysis in in vitro assays focusing on histone-polyphosphate interactions. METHODS: Transmission electron microscopy and dynamic light scattering for stability of the PolyP-NP preparations. Turbidimetry for kinetics of fibrinogen clotting by thrombin and fibrin dissolution by tissue-type plasminogen activator/plasminogen. Scanning electron microscopy for fibrin structure. Surface plasmon resonance for strength of histone-PolyP interactions. RESULTS: Both linear PolyP and PolyP-NP accelerated the fibrin formation and slowed down its dissolution and these effects were strongly dependent on the number of individual PolyP particles and not on their size. Addition of DNA did not modify significantly the PolyP-NP effects on fibrin formation and lysis. Both linear and nanoparticulate PolyP counteracted the effect of histone in the acceleration of fibrinogen clotting by thrombin. PolyP-NP, but not linear PolyP enhanced the prolongation of lysis time in fibrin containing histone and caused more pronounced thickening of the fibrin fibers than the linear form. Finally, PolyP-NP bound weaker to histone than the linear form. CONCLUSIONS: The interaction of PolyP with histone was a stronger modulator of fibrin formation and lysis than its interaction with DNA. In addition, the PolyP nanoparticles enhanced the thrombus stabilizing effects of histone more effectively than linear PolyP.


Assuntos
Nanopartículas , Trombose , DNA , Fibrina/metabolismo , Fibrinogênio/metabolismo , Histonas , Humanos , Polifosfatos/metabolismo , Trombina/metabolismo , Trombose/metabolismo
10.
J Neuroinflammation ; 19(1): 68, 2022 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-35305649

RESUMO

BACKGROUND: Peripheral nerve injuries are accompanied by inflammatory reactions, over-activation of which may hinder recovery. Among pro-inflammatory pathways, inflammasomes are one of the most potent, leading to release of active IL-1ß. Our aim was to understand how inflammasomes participate in central inflammatory reactions accompanying peripheral nerve injury. METHODS: After axotomy of the sciatic nerve, priming and activation of the NLRP3 inflammasome was examined in cells of the spinal cord. Regeneration of the nerve was evaluated after coaptation using sciatic functional index measurements and retrograde tracing. RESULTS: In the first 3 days after the injury, elements of the NLRP3 inflammasome were markedly upregulated in the L4-L5 segments of the spinal cord, followed by assembly of the inflammasome and secretion of active IL-1ß. Although glial cells are traditionally viewed as initiators of neuroinflammation, in this acute phase of inflammation, inflammasome activation was found exclusively in affected motoneurons of the ventral horn in our model. This process was significantly inhibited by 5-BDBD, a P2X4 receptor inhibitor and MCC950, a potent NLRP3 inhibitor. Although at later time points the NLRP3 protein was upregulated in microglia too, no signs of inflammasome activation were detected in these cells. Inhibition of inflammasome activation in motoneurons in the first days after nerve injury hindered development of microgliosis in the spinal cord. Moreover, P2X4 or inflammasome inhibition in the acute phase significantly enhanced nerve regeneration on both the morphological and the functional levels. CONCLUSIONS: Our results indicate that the central reaction initiated by sciatic nerve injury starts with inflammasome activation in motoneurons of the ventral horn, which triggers a complex inflammatory reaction and activation of microglia. Inhibition of neuronal inflammasome activation not only leads to a significant reduction of microgliosis, but has a beneficial effect on the recovery as well.


Assuntos
Inflamassomos , Traumatismos dos Nervos Periféricos , Humanos , Inflamassomos/metabolismo , Neurônios Motores/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Doenças Neuroinflamatórias , Nervo Isquiático/lesões
11.
Biol Futur ; 73(1): 31-42, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34837645

RESUMO

Lysosome (L), a hydrolytic compartment of the endo-lysosomal system (ELS), plays a central role in the metabolic regulation of eukaryotic cells. Furthermore, it has a central role in the cytopathology of several diseases, primarily in lysosomal storage diseases (LSDs). Mucopolysaccharidosis II (MPS II, Hunter disease) is a rare LSD caused by idunorate-2-sulphatase (IDS) enzyme deficiency. To provide a new platform for drug development and clarifying the background of the clinically observed cytopathology, we established a human in vitro model, which recapitulates all cellular hallmarks of the disease. Some of our results query the traditional concept by which the storage vacuoles originate from the endosomal system and suggest a new concept, in which endoplasmic reticulum-Golgi intermediate compartment (ERGIC) and RAB2/LAMP positive Golgi (G) vesicles play an initiative role in the vesicle formation. In this hypothesis, Golgi is not only an indirectly affected organelle but enforced to be the main support of vacuole formation. The purposes of this minireview are to give a simple guide for understanding the main relationships in ELS, to present the storage vacuoles and their relation to ELS compartments, to recommend an alternative model for vacuole formation, and to place the Golgi in spotlight of MPS II cytopathology.


Assuntos
Mucopolissacaridose II , Endocitose , Complexo de Golgi/metabolismo , Humanos , Lisossomos/metabolismo , Mucopolissacaridose II/metabolismo , Vacúolos/metabolismo
12.
Biol Futur ; 72(3): 367-372, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34554557

RESUMO

The extracts of 7 herbs were screened and compared for their functional ability to inhibit the aggregation of trypsin as an appropriate model protein for in vitro fibrillation in aqueous ethanol at pH 7.0. Turbidity measurements, total phenolic content determination, aggregation kinetics, Congo red binding assay as well as transmission electron microscopy were used to analyse the inhibition of amyloid fibril formation. This correlated with the total phenolic content of the herb extracts. The peppermint extract proved to be the most potent anti-amyloidogenic agent. Results showed that the peppermint extract exerted dose-dependent inhibitory effect on trypsin fibril formation.


Assuntos
Óleos de Plantas/farmacologia , Agregados Proteicos/efeitos dos fármacos , Agregação Patológica de Proteínas/tratamento farmacológico , Mentha piperita/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Óleos de Plantas/metabolismo
13.
Int J Mol Sci ; 22(11)2021 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-34204159

RESUMO

By upregulation of cell adhesion molecules and secretion of proinflammatory cytokines, cells of the neurovascular unit, including pericytes and endothelial cells, actively participate in neuroinflammatory reactions. As previously shown, both cell types can activate inflammasomes, cerebral endothelial cells (CECs) through the canonical pathway, while pericytes only through the noncanonical pathway. Using complex in vitro models, we demonstrate here that the noncanonical inflammasome pathway can be induced in CECs as well, leading to a further increase in the secretion of active interleukin-1ß over that observed in response to activation of the canonical pathway. In parallel, a more pronounced disruption of tight junctions takes place. We also show that CECs respond to inflammatory stimuli coming from both the apical/blood and the basolateral/brain directions. As a result, CECs can detect factors secreted by pericytes in which the noncanonical inflammasome pathway is activated and respond with inflammatory activation and impairment of the barrier properties. In addition, upon sensing inflammatory signals, CECs release inflammatory factors toward both the blood and the brain sides. Consequently, CECs activate pericytes by upregulating their expression of NLRP3 (NOD-, LRR-, and pyrin domain-containing protein 3), an inflammasome-forming pattern recognition receptor. In conclusion, cerebral pericytes and endothelial cells mutually activate each other in inflammation.


Assuntos
Encéfalo/patologia , Comunicação Celular , Células Endoteliais/patologia , Inflamassomos/metabolismo , Pericitos/patologia , Transdução de Sinais , Animais , Inflamação/metabolismo , Inflamação/patologia , Suínos , Junções Íntimas/metabolismo
14.
Cancer Biomark ; 32(3): 353-362, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34151834

RESUMO

BACKGROUND: Recent studies proved that metabolic changes in malignant disorders have an impact on protein glycosylation, however, only a few attempts have been made so far to use O-GlcNAc analysis as a prognostic tool. Glucose metabolism is reported to be altered in hematological malignancies thus, we hypothesized that monitoring intracellular O-GlcNAc levels in Rai stage 0-I (Binet A) CLL patients could give deeper insights regarding subtle metabolic changes of progression which are not completely detected by the routine follow-up procedures. OBJECTIVE: In this proof of concept study we established a flow cytometric detection method for the assessment of O-GlcNAcylation as a possible prognostic marker in CLL malignancy which was supported by fluorescence microscopy. METHODS: Healthy volunteers and CLL patients were recruited for this study. Lymphocytes were isolated, fixed and permeabilised by various methods to find the optimal experimental condition for O-GlcNAc detection by flow cytometry. O-GlcNAc levels were measured and compared to lymphocyte count and various blood parameters including plasma glucose level. RESULTS: The protocol we developed includes red blood cell lysis, formalin fixation, 0.1% Tween 20 permeabilisation and employs standardized cell number per sample and unstained controls. We have found significant correlation between O-GlcNAc levels and WBC (R2= 0.8535, p< 0.0029) and lymphocyte count (R2= 0.9225, p< 0.0006) in CLL patients. Interestingly, there was no such correlation in healthy individuals (R2= 0.05664 for O-GlcNAc vs WBC and R2= 0.04379 for O-GlcNAc vs lymphocytes). CONCLUSION: Analyzing O-GlcNAc changes in malignant disorders, specifically in malignant hematologic diseases such as CLL, could be a useful tool to monitor the progression of the disease.


Assuntos
Citometria de Fluxo/métodos , Leucemia Linfocítica Crônica de Células B/sangue , Estudos de Casos e Controles , Feminino , Glicosilação , Humanos , Masculino , Estadiamento de Neoplasias , Prognóstico , Estudo de Prova de Conceito
15.
Int J Mol Sci ; 22(10)2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-34069135

RESUMO

Triple negative breast cancer presents higher mortality and poorer survival rates than other breast cancer (BC) types, due to the proneness to brain metastases formation, which are usually diagnosed at advanced stages. Therefore, the discovery of BC brain metastases (BCBM) biomarkers appears pivotal for a timely intervention. With this work, we aimed to disclose microRNAs (miRNAs) and extracellular vesicles (EVs) in the circulation as biomarkers of BCBM formation. Using a BCBM animal model, we analyzed EVs in plasma by nanoparticle tracking analysis and ascertained their blood-brain barrier (BBB) origin by flow cytometry. We further evaluated circulating miRNAs by RT-qPCR and their brain expression by in situ hybridization. In parallel, a cellular model of BCBM formation, combining triple negative BC cells and BBB endothelial cells, was used to differentiate the origin of biomarkers. Established metastases were associated with an increased content of circulating EVs, particularly of BBB origin. Interestingly, deregulated miRNAs in the circulation were observed prior to BCBM detection, and their brain origin was suggested by matching alterations in brain parenchyma. In vitro studies indicated that miR-194-5p and miR-205-5p are expressed and released by BC cells, endothelial cells and during their interaction. These results highlight miRNAs and EVs as biomarkers of BCBM in early and advanced stages, respectively.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/patologia , MicroRNA Circulante/sangue , Vesículas Extracelulares/patologia , Animais , Barreira Hematoencefálica , Neoplasias Encefálicas/secundário , Neoplasias da Mama/genética , Linhagem Celular Tumoral , MicroRNA Circulante/genética , Endotélio Vascular/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos Endogâmicos BALB C , MicroRNAs/genética , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Colloids Surf B Biointerfaces ; 204: 111810, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33965749

RESUMO

Despite of advances in modern therapeutics, one of the most feared complications of cancer are brain metastases, which often cause life impairing profound neurological symptoms and premature death. Breast adenocarcinoma is among the leading "sources" of brain metastases. Since the central nervous system lacks a classical lymphatic circulation, invading metastatic cells can reach the brain parenchyma only through haematogenous routes and must breach the blood-brain barrier (BBB). The key step before the transmigration of metastatic cells through the highly regulated interface of the BBB is the establishment of firm adhesion between the tumor cell and the cerebral endothelial layer. Using atomic force microscopy, as a high resolution force spectrograph, direct measurements of intercellular interactions was performed between living adenocarcinoma cells and a confluent endothelial layer pre-treated with carcinoma cell-derived exosomes. By immobilization of a living adenocarcinoma cell to an atomic force microscope's cantilever, intercellular de-adhesions were directly measured by single cell force spectroscopy (SCFS) at quasi-physiological conditions. De-adhesion dynamics and strength was characterized by several different calculated parameters, involving aspects of both membrane and cell surface related factors. Our results indicate that de-adhesion strength was lower in case of exosome pre-treated endothelial cells as compared to non-treated controls. Breast adenocarcinoma-derived exosomes have direct effect on de-adhesion pattern of brain endothelium.


Assuntos
Adenocarcinoma , Exossomos , Encéfalo , Adesão Celular , Células Endoteliais , Endotélio , Humanos , Microscopia de Força Atômica
17.
Cancers (Basel) ; 13(4)2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33671551

RESUMO

With breast cancer (BC) therapy improvements, the appearance of brain metastases has been increasing, representing a life-threatening condition. Brain metastasis formation involves BC cell (BCC) extravasation across the blood-brain barrier (BBB) and brain colonization by unclear mechanisms. We aimed to disclose the actors involved in BC brain metastasis formation, focusing on BCCs' phenotype, growth factor expression, and signaling pathway activation, correlating with BBB alterations and intercellular communication. Hippocampi of female mice inoculated with 4T1 BCCs were examined over time by hematoxylin-eosin, immunohistochemistry and immunofluorescence. Well-established metastases were observed at seven days, increasing thereafter. BCCs entering brain parenchyma presented mesenchymal, migratory, and proliferative features; however, with time, they increasingly expressed epithelial markers, reflecting a mesenchymal-epithelial transition. BCCs also expressed platelet-derived growth factor-B, ß4 integrin, and focal adhesion kinase, suggesting autocrine and/or paracrine regulation with adhesion signaling activation, while balance between Rac1 and RhoA was associated with the motility status. Intercellular communication via gap junctions was clear among BCCs, and between BCCs and endothelial cells. Thrombin accumulation, junctional protein impairment, and vesicular proteins increase reflect BBB alterations related with extravasation. Expression of plasmalemma vesicle-associated protein was increased in BCCs, along with augmented vascularization, whereas pericyte contraction indicated mural cells' activation. Our results provide further understanding of BC brain metastasis formation, disclosing potential therapeutic targets.

18.
Pharmaceutics ; 13(1)2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33466551

RESUMO

By being an antagonist of glutamate and other receptors, kynurenic acid serves as an endogenous neuroprotectant in several pathologies of the brain. Unfortunately, systemic administration of kynurenic acid is hindered by its low permeability through the blood-brain barrier. One possibility to overcome this problem is to use analogues with similar biological activity as kynurenic acid, but with an increased permeability through the blood-brain barrier. We synthesized six novel aminoalkylated amide derivatives of kynurenic acid, among which SZR-104 (N-(2-(dimethylamino)ethyl)-3-(morpholinomethyl)-4-hydroxyquinoline-2-carboxamide) proved to have the highest permeability through an in vitro blood-brain barrier model. In addition, permeability of SZR-104 was significantly higher than that of kynurenic acid, xanthurenic acid and 39B, a quinolone derivative/xanthurenic acid analogue. Since peripherally administered SZR-104 is able to inhibit epileptiform activity in the brain, we conclude that SZR-104 is a promising kynurenic acid analogue with good penetrability into the central nervous system.

19.
J Appl Toxicol ; 41(3): 387-398, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32830870

RESUMO

Emerging infectious diseases are major drivers of global and local amphibian biodiversity loss. Therefore, developing effective disinfection methods to manage the impact of diseases in wild and captive "ark" populations are an important goal in amphibian conservation. While chemical disinfectants have been used safely and effectively in larval and adult amphibians infected with pathogenic microbes, their applicability to amphibian egg masses has remained untested. To bridge this gap, we exposed embryos of the common toad (Bufo bufo) and agile frog (Rana dalmatina) experimentally to three widely used disinfectants: voriconazole, chloramphenicol and chlorogen-sesquihydrate. For 3 days we exposed portions of egg masses to these disinfectants at 1×, 2×, 5× and 10× the concentration recommended for the disinfection of tadpoles and adults. Subsequently, we recorded embryonic and larval survival, as well as larval body mass and the incidence of abnormalities 12 days after hatching. Application of voriconazole had species- and concentration-dependent negative impacts on survival and body mass, and caused marked malformations in the viscerocranial structure of B. bufo tadpoles. Exposure to chlorogen-sesquihydrate also resulted in significant mortality in B. bufo embryos and negatively affected body mass of R. dalmatina larvae. Chloramphenicol had little negative effects on embryos or larvae in either species. Based on these results, the application of voriconazole and chlorogen-sesquihydrate cannot be recommended for the disinfection of amphibian eggs, whereas treatment with chloramphenicol appears to be a safe method for eliminating potential pathogens from anuran egg masses and their immediate aquatic environment.


Assuntos
Batrachochytrium/crescimento & desenvolvimento , Desinfetantes/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Óvulo/efeitos dos fármacos , Óvulo/crescimento & desenvolvimento , Ranidae/embriologia , Animais , Cloranfenicol/toxicidade , Hungria , Voriconazol/toxicidade
20.
Front Pharmacol ; 11: 584184, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33328988

RESUMO

Neuronal injuries are accompanied by release and accumulation of damage-associated molecules, which in turn may contribute to activation of the immune system. Since a wide range of danger signals (including endogenous ones) are detected by the nucleotide-binding oligomerization domain-, LRR- and pyrin domain-containing protein 3 (NLRP3) pattern recognition receptor, we hypothesized that NLRP3 may become activated in response to motor neuron injury. Here we show that peripheral injury of the oculomotor and the hypoglossal nerves results in upregulation of NLRP3 in corresponding motor nuclei in the brainstem of mice. Although basal expression of NLRP3 was observed in microglia, astroglia and neurons as well, its upregulation and co-localization with apoptosis-associated speck-like protein containing a caspase activation and recruitment domain, suggesting inflammasome activation, was only detected in neurons. Consequently, increased production of active pro-inflammatory cytokines interleukin-1ß and interleukin-18 were detected after hypoglossal nerve axotomy. Injury-sensitive hypoglossal neurons responded with a more pronounced NLRP3 upregulation than injury-resistant motor neurons of the oculomotor nucleus. We further demonstrated that the mitochondrial protector diazoxide was able to reduce NLRP3 upregulation in a post-operative treatment paradigm. Our results indicate that NLRP3 is activated in motoneurons following acute nerve injury. Blockade of NLRP3 activation might contribute to the previously observed anti-inflammatory and neuroprotective effects of diazoxide.

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