Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 45
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Glia ; 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32003513

RESUMO

Astrogliosis comprises a variety of changes in astrocytes that occur in a context-specific manner, triggered by temporally diverse signaling events that vary with the nature and severity of brain insults. However, most mechanisms underlying astrogliosis were described using animals, which fail to reproduce some aspects of human astroglial signaling. Here, we report an in vitro model to study astrogliosis using human-induced pluripotent stem cells (iPSC)-derived astrocytes which replicate temporally intertwined aspects of reactive astrocytes in vivo. We analyzed the time course of astrogliosis by measuring nuclear translocation of NF-kB, production of cytokines, changes in morphology and function of iPSC-derived astrocytes exposed to TNF-α. We observed NF-kB p65 subunit nuclear translocation and increased gene expression of IL-1ß, IL-6, and TNF-α in the first hours following TNF-α stimulation. After 24 hr, conditioned media from iPSC-derived astrocytes exposed to TNF-α exhibited increased secretion of inflammation-related cytokines. After 5 days, TNF-α-stimulated cells presented a typical phenotype of astrogliosis such as increased immunolabeling of Vimentin and GFAP and nuclei with elongated shape and shrinkage. Moreover, ~50% decrease in aspartate uptake was observed during the time course of astrogliosis with no evident cell damage, suggesting astroglial dysfunction. Together, our results indicate that human iPSC-derived astrocytes reproduce canonical events associated with astrogliosis in a time dependent fashion. The approach described here may contribute to a better understanding of mechanisms governing human astrogliosis with potential applicability as a platform to uncover novel biomarkers and drug targets to prevent or mitigate astrogliosis associated with human brain disorders.

2.
J Cell Mol Med ; 24(1): 88-97, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31654493

RESUMO

We aim to characterize the kinetics of early and late microglial phenotypes after systemic inflammation in an animal model of severe sepsis and the effects of minocycline on these phenotypes. Rats were subjected to CLP, and some animals were treated with minocycline (10 ug/kg) by i.c.v. administration. Animals were killed 24 hours, 5, 10 and 30 days after sepsis induction, and serum and hippocampus were collected for subsequent analyses. Real-time PCR was performed for M1 and M2 markers. TNF-α, IL-1ß, IL-6, IL-10, CCL-22 and nitrite/nitrate levels were measured. Immunofluorescence for IBA-1, CD11b and arginase was also performed. We demonstrated that early after sepsis, there was a preponderant up-regulation of M1 markers, and this was not switched to M2 phenotype markers later on. We found that up-regulation of both M1 and M2 markers co-existed up to 30 days after sepsis induction. In addition, minocycline induced a down-regulation, predominantly, of M1 markers. Our results suggest early activation of M1 microglia that is followed by an overlap of both M1 and M2 phenotypes and that the beneficial effects of minocycline on sepsis-associated brain dysfunction may be related to its effects predominantly on the M1 phenotype.

3.
Food Chem Toxicol ; 133: 110766, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31430511

RESUMO

People with large amounts of adipose tissue are more vulnerable and more likely to develop diseases where oxidative stress and inflammation play a pivotal role, than persons with a healthy weight. Atmospheric contamination is a reality to which a large part of the worldwide population is exposed. Half of today's global electrical energy is derived from coal. Each organism, in its complexity, responds in different ways to dietary compounds and air pollution. The objective of this study was to investigate the effects of obesity and coal ash inhalation within the parameters of oxidative damage and inflammation in different regions of the brain of rats. A diet containing high-fat concentration was administered chronically to rats, along with exposure to coal ash, simulating the contamination that occurs daily throughout human life. High-resolution transmission electron microscopy was performed to identify the particles present in coal ash samples. Our results demonstrated that obese rats exposed to coal ash inhalation were more affected by oxidative damage with subsequent systemic inflammation in the hippocampus. Since there is an inflammatory predisposition caused by obesity, the inhalation of nanoparticles increases the levels of free radicals, resulting in systemic inflammation and oxidative damage, which can lead to chronic neurodegeneration.


Assuntos
Cinza de Carvão/toxicidade , Hipocampo/efeitos dos fármacos , Inflamação/metabolismo , Exposição por Inalação , Obesidade/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Poluentes Atmosféricos/toxicidade , Animais , Catalase/metabolismo , Dieta Hiperlipídica , Glutationa Peroxidase/metabolismo , Inflamação/induzido quimicamente , Masculino , Ratos Wistar , Superóxido Dismutase/metabolismo
4.
Mol Cell Biochem ; 462(1-2): 11-23, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31446616

RESUMO

BRCA-1 is a nuclear protein involved in DNA repair, transcriptional regulation, and cell cycle control. Its involvement in other cellular processes has been described. Here, we aimed to investigate the role of BRCA-1 in macrophages M(LPS), M(IL-4), and tumor cell-induced differentiation. We used siRNAs to knockdown BRCA-1 in RAW 264.7 macrophages exposed to LPS, IL-4, and C6 glioma cells conditioned medium (CMC6), and evaluated macrophage differentiation markers and functional phagocytic activity as well as DNA damage and cell survival in the presence and absence of BRCA-1. LPS and CMC6, but not by IL-4, increased DNA damage in macrophages, and this effect was more pronounced in BRCA-1-depleted cells, including M(IL-4). BRCA-1 depletion impaired expression of pro-inflammatory cytokines, TNF-α and IL-6, and reduced the phagocytic activity of macrophages in response to LPS. In CMC6-induced differentiation, BRCA-1 knockdown inhibited TNF-α and IL-6 expression which was accompanied by upregulation of the anti-inflammatory markers IL-10 and TGF-ß and reduced phagocytosis. In contrast, M(IL-4) phenotype was not affected by BRCA-1 status. Molecular docking predicted that the conserved BRCA-1 domain BRCT can interact with the p65 subunit of NF-κB. Immunofluorescence assays showed that BRCA-1 and p65 co-localize in the nucleus of LPS-treated macrophages and reporter gene assay showed that depletion of BRCA-1 decreased LPS and CMC6-induced NF-κB transactivation. IL-4 had no effect upon NF-κB. Taken together, our findings suggest a role of BRCA-1 in macrophage differentiation and phagocytosis induced by LPS and tumor cells secretoma, but not IL-4, in a mechanism associated with inhibition of NF-κB.


Assuntos
Proteína BRCA1/metabolismo , Polaridade Celular , Inflamação/patologia , Ativação de Macrófagos , Macrófagos/metabolismo , Macrófagos/patologia , NF-kappa B/metabolismo , Animais , Biomarcadores/metabolismo , Ciclo Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Polaridade Celular/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Dano ao DNA , Inflamação/metabolismo , Lipopolissacarídeos , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Metaloproteinases da Matriz/metabolismo , Camundongos , Fagocitose/efeitos dos fármacos , Células RAW 264.7 , RNA Interferente Pequeno/metabolismo , Ratos
5.
Cell Signal ; 62: 109356, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31288066

RESUMO

Recent studies have investigated the use of retinoic acid (RA) molecule in combined chemotherapies to cancer cells as an attempt to increase treatment efficiency and circumvent cell resistance. Positive results were obtained in clinical trials from lung cancer patients treated with RA and cisplatin. Meanwhile, the signalling process that results from the interaction of both molecules remains unclear. One of the pathways that RA is able to modulate is the activity of NRF2 transcription factor, which is highly associated with tumour progression and resistance. Therefore, the aim of this work was to investigate molecular mechanism of RA and cisplatin co-treatment in A549 cells, focusing in NRF2 pathway. To this end, we investigated NRF2 and NRF2-target genes expression, cellular redox status, cisplatin-induced apoptosis, autophagy and DNA repair through homologous recombination. RA demonstrated to have an inhibitory effect over NRF2 activation, which regulates the expression of thiol antioxidants enzymes. Moreover, RA increased reactive species production associated with increased oxidation of thiol groups within the cells. The expression of proteins associated with DNA repair through homologous recombination was also suppressed by RA pre-treatment. All combined, these effects appear to create a more sensitive cellular environment to cisplatin treatment, increasing apoptosis frequency. Interestingly, autophagy was also increased by combination therapy, suggesting a resistance mechanism by A549 cells. In conclusion, these results provided new information about molecular mechanisms of RA and cisplatin treatment contributing to chemotherapy optimization.

6.
Front Neurol ; 10: 221, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30930837

RESUMO

The presence of autoantibodies against neuronal cell surface or synaptic proteins and their relationship to autoimmune encephalitis have recently been characterized. These autoantibodies have been also reported in other pathologic conditions; however, their role during sepsis is not known. This study detected the presence of autoantibodies against neuronal cell surface or synaptic proteins in the serum of septic patients and determined their relationship to the occurrence of brain dysfunction and mortality. This prospective, observational cohort study was performed in four Brazilian intensive care units (ICUs). Sixty patients with community-acquired severe sepsis or septic shock admitted to the ICU were included. Blood samples were collected from patients within 24 h of ICU admission. Antibodies to six neuronal proteins were assessed, including glutamate receptors (types NMDA, AMPA1, and AMPA2); voltage-gated potassium channel complex (VGKC) proteins, leucine-rich glioma-inactivated protein 1 (LGI1), and contactin-associated protein-2 (Caspr2), as well as the GABAB1 receptor. There was no independent association between any of the measured autoantibodies and the occurrence of brain dysfunction (delirium or coma). However, there was an independent and significant relationship between anti-NMDAR fluorescence intensity and hospital mortality. In conclusion, anti-NMDAR was independently associated with hospital mortality but none of the measured antibodies were associated with brain dysfunction in septic patients.

7.
Phytother Res ; 33(5): 1394-1403, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30868680

RESUMO

Obesity is a metabolic disorder associated with adverse health consequences that has increased worldwide at an epidemic rate. This has encouraged many people to utilize nonprescription herbal supplements for weight loss without knowledge of their safety or efficacy. However, mounting evidence has shown that some herbal supplements used for weight loss are associated with adverse effects. Guarana seed powder is a popular nonprescription dietary herb supplement marketed for weight loss, but no study has demonstrated its efficacy or safety when administered alone. Wistar rats were fed four different diets (low-fat diet and Western diet with or without guarana supplementation) for 18 weeks. Metabolic parameters, gut microbiota changes, and toxicity were then characterized. Guarana seed powder supplementation prevented weight gain, insulin resistance, and adipokine dysregulation induced by Western diet compared with the control diet. Guarana induced brown adipose tissue expansion, mitochondrial biogenesis, uncoupling protein-1 overexpression, AMPK activation, and minor changes in gut microbiota. Molecular docking suggested a direct activation of AMPK by four guarana compounds tested here. We propose that brown adipose tissue activation is one of the action mechanisms involved in guarana supplementation-induced weight loss and that direct AMPK activation may underlie this mechanism. In summary, guarana is an attractive potential therapeutic agent to treat obesity.


Assuntos
Adipocinas/metabolismo , Tecido Adiposo Marrom/efeitos dos fármacos , Resistência à Insulina , Paullinia/química , Animais , Dieta Hiperlipídica/efeitos adversos , Dieta Ocidental , Suplementos Nutricionais , Humanos , Masculino , Simulação de Acoplamento Molecular , Obesidade/metabolismo , Ratos , Ratos Wistar , Ganho de Peso , Perda de Peso/efeitos dos fármacos
8.
Neurochem Int ; 126: 27-35, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30849398

RESUMO

Carvacrol (CARV) presents valuable biological properties such as anti-inflammatory and antioxidant activities. However, pharmacological uses of CARV are largely limited due to disadvantages related to solubility, bioavailability, preparation and storage processes. The complexation of monoterpenes with ß-cyclodextrin (ß-CD) increases their stability, solubility and oral bioavailability. Here, the protective effect of oral treatment with CARV/ß-CD complex (25 µg/kg/day) against dopaminergic (DA) denervation induced by unilateral intranigral injection of 6-hydroxydopamine (6-OHDA - 10 µg per rat) was analyzed, in order to evaluate a putative application in the development of neuroprotective therapies for Parkinson's disease (PD). Pretreatment with CARV/ß-CD for 15 days prevented the loss of DA neurons induced by 6-OHDA in adult Wistar rats. This effect may occur through CARV anti-inflammatory and antioxidant properties, as the pretreatment with CARV/ß-CD inhibited the release of IL-1ß and TNF-α; besides, CARV prevented the increase of mitochondrial superoxide production induced by 6-OHDA in cultured SH-SY5Y cells. Importantly, hepatotoxicity or alterations in blood cell profile were not observed with oral administration of CARV/ß-CD. Therefore, this study showed a potential pharmacological application of CARV/ß-CD in PD using a non-invasive route of drug delivery, i.e., oral administration.


Assuntos
/administração & dosagem , Denervação/efeitos adversos , Neurônios Dopaminérgicos/efeitos dos fármacos , Fármacos Neuroprotetores/administração & dosagem , Oxidopamina/toxicidade , beta-Ciclodextrinas/administração & dosagem , Administração Oral , Animais , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Combinação de Medicamentos , Masculino , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Ratos , Ratos Wistar
9.
Neurochem Int ; 125: 25-34, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30739037

RESUMO

Vitamin A (retinol) is involved in signaling pathways regulating gene expression and was postulated to be a major antioxidant and anti-inflammatory compound of the diet. Parkinson's disease (PD) is a progressive neurodegenerative disorder, characterized by loss of nigral dopaminergic neurons, involving oxidative stress and pro-inflammatory activation. The aim of the present study was to evaluate the neuroprotective effects of retinol oral supplementation against 6-hydroxydopamine (6-OHDA, 12 µg per rat) nigrostriatal dopaminergic denervation in Wistar rats. Animals supplemented with retinol (retinyl palmitate, 3000 IU/kg/day) during 28 days exhibited increased retinol content in liver, although circulating retinol levels (serum) were unaltered. Retinol supplementation did not protect against the loss of dopaminergic neurons (assessed through tyrosine hydroxylase immunofluorescence and Western blot). Retinol supplementation prevented the effect of 6-OHDA on Iba-1 levels but had no effect on 6-OHDA-induced GFAP increase. Moreover, GFAP levels were increased by retinol supplementation alone. Rats pre-treated with retinol did not present oxidative damage or thiol redox modifications in liver, and the circulating levels of TNF-α, IL-1ß, IL-6 and IL-10 were unaltered by retinol supplementation, demonstrating that the protocol used here did not cause systemic toxicity to animals. Our results indicate that oral retinol supplementation is not able to protect against 6-OHDA-induced dopaminergic denervation, and it may actually stimulate astrocyte reactivity without altering parameters of systemic toxicity.


Assuntos
Modelos Animais de Doenças , Neurônios Dopaminérgicos/efeitos dos fármacos , Degeneração Neural/induzido quimicamente , Degeneração Neural/tratamento farmacológico , Simpatectomia Química/métodos , Vitamina A/administração & dosagem , Administração Oral , Animais , Neurônios Dopaminérgicos/metabolismo , Masculino , Degeneração Neural/metabolismo , Técnicas de Cultura de Órgãos , Ratos , Ratos Wistar , Resultado do Tratamento
10.
Mol Neurobiol ; 56(5): 3079-3089, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30094805

RESUMO

The receptor for advanced glycation endproducts (RAGE) is a transmembrane, immunoglobulin-like receptor that interacts with a broad repertoire of extracellular ligands. RAGE belongs to a family of cell adhesion molecules and is considered a key receptor in the inflammation axis and a potential contributor to the neurodegeneration. The present study aimed to investigate the content and cell localization of RAGE in the brain of Wistar rats subjected to systemic inflammation induced by a single dose of lipopolysaccharide (LPS, 5 mg/kg, i.p.). Fifteen days after LPS administration, the content of RAGE was analyzed in the prefrontal cortex (PFC), hippocampus (HIPP), cerebellum (CB), and substantia nigra (SN) were investigated. RAGE levels increased in all structures, except HIPP; however, immunohistochemistry analysis demonstrated that the cell site of RAGE expression changed from blood vessel-like structures to neuronal cells in all brain areas. Besides, the highest level of RAGE expression was found in SN. Immunofluorescence analysis in SN confirmed that RAGE expression was mainly co-localized in endothelial cells (RAGE/PECAM-1 co-staining) in untreated animals, while LPS-treated animals had RAGE expression predominantly in dopaminergic neurons (RAGE/TH co-staining). Decreased TH levels, as well as increased pro-inflammatory markers (TNF-α, IL-1ß, Iba-1, GFAP, and phosphorylated ERK1/2) in SN, occurred concomitantly to RAGE stimulation in the same site. These results suggest a role for RAGE in the establishment of a neuroinflammation-neurodegeneration axis that develops as a long-term response to systemic inflammation by LPS.


Assuntos
Encéfalo/metabolismo , Encéfalo/patologia , Células Endoteliais/metabolismo , Inflamação/metabolismo , Neurônios/metabolismo , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Animais , Biomarcadores/metabolismo , Neurônios Dopaminérgicos/metabolismo , Inflamação/patologia , Lipopolissacarídeos/farmacologia , Masculino , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Ratos Wistar , Substância Negra/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo
11.
Ecotoxicol Environ Saf ; 165: 44-51, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30179764

RESUMO

Obesity is an important nutritional disorder worldwide. Its association with environmental pollution may trigger an increase in oxidative stress and inflammatory parameters. Coal is a resource used throughout the world as an important fuel source for generating electricity. The ashes released by the coal combustion cause serious problems for human health due to their high toxicity and their capacity to bioaccumulate. The aim of this work was to investigate the effects of coal dust inhalation in the organs of obese and non-obese Wistar rats. Pro-inflammatory cytokines, oxidative stress, oxidative damage, histological analysis, comet assay, and micronuclei were investigated. Both obesity and coal dust inhalation increased the pro-inflammatory cytokines IL-1ß and TNF-α and decreased HSP70 levels in serum, however, in obese animals that inhaled coal dust these changes were more pronounced. Liver histological analysis showed severe microvesicular steatosis in obese animals that inhaled coal dust. Lung histologic investigation showed abnormalities in lung structure of animals exposed to coal dust and showed severe lung distensibility in obese animals exposed to coal dust. The comet assay showed DNA damage in animals subjected to coal. In addition, there were modulations in enzymatic activities and damage to protein and lipids. Based on our results, the coal dust inhalation can potentiate the pro-inflammatory profile present in obese rats. We also observed an increase in the protein oxidative damage in obese rats that inhaled coal dust. Taken together, our results suggest that the combination of obesity and coal inhalation increased the risks of the development of diseases related to oxidative stress and inflammation.


Assuntos
Carvão Mineral/toxicidade , Dano ao DNA , Obesidade/patologia , Estresse Oxidativo , Administração por Inalação , Animais , Citocinas/sangue , Poeira , Mediadores da Inflamação/sangue , Fígado/efeitos dos fármacos , Fígado/patologia , Pulmão/efeitos dos fármacos , Pulmão/patologia , Masculino , Obesidade/sangue , Obesidade/metabolismo , Ratos , Ratos Wistar
12.
Neurotoxicology ; 66: 98-106, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29588162

RESUMO

Recent evidence shows that aminochrome induces glial activation related to neuroinflammation. This dopamine derived molecule induces formation and stabilization of alpha-synuclein oligomers, mitochondria dysfunction, oxidative stress, dysfunction of proteasomal and lysosomal systems, endoplasmic reticulum stress and disruption of the microtubule network, but until now there has been no evidence of effects on production of cytokines and neurotrophic factors, that are mechanisms involved in neuronal loss in Parkinson's disease (PD). This study examines the potential role of aminochrome on the regulation of NGF, GDNF, TNF-α and IL-1ß production and microglial activation in organotypic midbrain slice cultures from P8 - P9 Wistar rats. We demonstrated aminochrome (25 µM, for 24 h) induced reduction of GFAP expression, reduction of NGF and GDNF mRNA levels, morphological changes in Iba1+ cells, and increase of both TNF-α, IL-1ß mRNA and protein levels. Moreover, aminochrome (25 µM, for 48 h) induced morphological changes in the edge of slices and reduction of TH expression. These results demonstrate neuroinflammation, as well as negative regulation of neurotrophic factors (GDNF and NGF), may be involved in aminochrome-induced neurodegeneration, and they contribute to a better understanding of PD pathogenesis.


Assuntos
Encefalite/induzido quimicamente , Indolquinonas/toxicidade , Mesencéfalo/efeitos dos fármacos , Doença de Parkinson/metabolismo , Animais , Encefalite/metabolismo , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Interleucina-1beta/metabolismo , Mesencéfalo/metabolismo , Microglia/efeitos dos fármacos , Microglia/metabolismo , Fator de Crescimento Neural/metabolismo , Ratos Wistar , Técnicas de Cultura de Tecidos , Fator de Necrose Tumoral alfa/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo
13.
J Biochem ; 163(6): 515-523, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29365096

RESUMO

The receptor for advanced glycation end products (RAGE) is a multi-ligand receptor, which activation amplifies and perpetuates inflammatory reactions. RAGE activation also strongly stimulates the production of reactive oxygen species, leading an imbalance of redox cellular state. The extent of liver damage caused by inflammation is crucial to the systemic response during proinflammatory episodes. To investigate the role of RAGE in liver damage caused by systemic inflammation, we evaluated the effect of RAGE blocking in oxidative stress parameters induced by systemic lipopolysaccharide (LPS) injection. Wistar rats received an intraperitoneal injection of RAGE antibody (50 mg/kg), 1 h prior intraperitoneal injection of LPS (5 mg/kg). Twenty-four hours later, the liver was isolated for analysis. The LPS-induced effect in protein oxidative damage, mitochondrial complex II activity, catalase activity, signal transducer and activator of transcription 3 phosphorylation and caspase 3 activation was prevented by prior treatment with RAGE antibody. However, RAGE blocking was not able to inhibit reactive oxygen species production and the impairment in non-enzymatic antioxidant capacity induced by LPS. The present results indicate that RAGE is an important mediator of liver oxidative damage induced by an acute systemic injection of LPS, although other mechanisms may also be responsible for liver function impairment during inflammation.


Assuntos
Anticorpos/imunologia , Lipopolissacarídeos/administração & dosagem , Lipopolissacarídeos/imunologia , Fígado/metabolismo , Estresse Oxidativo , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidores , Receptor para Produtos Finais de Glicação Avançada/imunologia , Animais , Anticorpos/administração & dosagem , Anticorpos/farmacologia , Inflamação/imunologia , Inflamação/metabolismo , Injeções Intraperitoneais , Fígado/efeitos dos fármacos , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Receptor para Produtos Finais de Glicação Avançada/metabolismo
14.
Mol Neurobiol ; 55(1): 741-750, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28050793

RESUMO

High glycine (GLY) levels have been suggested to induce neurotoxic effects in the central nervous system of patients with nonketotic hyperglycinemia (NKH). Since the mechanisms involved in the neuropathophysiology of NKH are not totally established, we evaluated the effect of a single intracerebroventricular administration of GLY on the content of proteins involved in neuronal damage and inflammatory response, as well as on the phosphorylation of the MAPK p38, ERK1/2, and JNK in rat striatum and cerebral cortex. We also examined glial fibrillary acidic protein (GFAP) staining, a marker of glial reactivity. The parameters were analyzed 30 min or 24 h after GLY administration. GLY decreased Tau phosphorylation in striatum and cerebral cortex 30 min and 24 h after its administration. On the other hand, synaptophysin levels were decreased in striatum at 30 min and in cerebral cortex at 24 h after GLY injection. GLY also decreased the phosphorylation of p38, ERK1/2, and JNK 30 min after its administration in both brain structures. Moreover, GLY-induced decrease of p38 phosphorylation in striatum was attenuated by N-methyl-D-aspartate receptor antagonist MK-801. In contrast, synuclein, NF-κB, iκB, inducible nitric oxide synthase and nitrotyrosine content, and GFAP immunostaining were not altered by GLY infusion. It may be presumed that the decreased phosphorylation of MAPK associated with alterations of markers of neuronal injury induced by GLY may contribute to the neurological dysfunction observed in NKH.


Assuntos
Encéfalo/patologia , Glicina/administração & dosagem , Hiperglicinemia não Cetótica/patologia , Hiperglicinemia não Cetótica/fisiopatologia , Sistema de Sinalização das MAP Quinases , Neurônios/patologia , Animais , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/enzimologia , Corpo Estriado/patologia , Corpo Estriado/fisiopatologia , Maleato de Dizocilpina/farmacologia , Proteína Glial Fibrilar Ácida/metabolismo , Proteínas I-kappa B/metabolismo , Injeções Intraventriculares , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , NF-kappa B/metabolismo , Neurônios/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Fosforilação/efeitos dos fármacos , Ratos Wistar , Sinaptofisina/metabolismo , Tirosina/análogos & derivados , Tirosina/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Proteínas tau/metabolismo
15.
J Biol Chem ; 293(1): 226-244, 2018 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-29127203

RESUMO

Patients recovering from sepsis have higher rates of CNS morbidities associated with long-lasting impairment of cognitive functions, including neurodegenerative diseases. However, the molecular etiology of these sepsis-induced impairments is unclear. Here, we investigated the role of the receptor for advanced glycation end products (RAGE) in neuroinflammation, neurodegeneration-associated changes, and cognitive dysfunction arising after sepsis recovery. Adult Wistar rats underwent cecal ligation and perforation (CLP), and serum and brain (hippocampus and prefrontal cortex) samples were obtained at days 1, 15, and 30 after the CLP. We examined these samples for systemic and brain inflammation; amyloid-ß peptide (Aß) and Ser-202-phosphorylated Tau (p-TauSer-202) levels; and RAGE, RAGE ligands, and RAGE intracellular signaling. Serum markers associated with the acute proinflammatory phase of sepsis (TNFα, IL-1ß, and IL-6) rapidly increased and then progressively decreased during the 30-day period post-CLP, concomitant with a progressive increase in RAGE ligands (S100B, Nϵ-[carboxymethyl]lysine, HSP70, and HMGB1). In the brain, levels of RAGE and Toll-like receptor 4, glial fibrillary acidic protein and neuronal nitric-oxide synthase, and Aß and p-TauSer-202 also increased during that time. Of note, intracerebral injection of RAGE antibody into the hippocampus at days 15, 17, and 19 post-CLP reduced Aß and p-TauSer-202 accumulation, Akt/mechanistic target of rapamycin signaling, levels of ionized calcium-binding adapter molecule 1 and glial fibrillary acidic protein, and behavioral deficits associated with cognitive decline. These results indicate that brain RAGE is an essential factor in the pathogenesis of neurological disorders following acute systemic inflammation.


Assuntos
Produtos Finais de Glicação Avançada/metabolismo , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Encéfalo/metabolismo , Cognição/fisiologia , Disfunção Cognitiva/metabolismo , Hipocampo/metabolismo , Inflamação/metabolismo , Masculino , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/fisiopatologia , Fosforilação , Ratos , Ratos Wistar , Sepse/complicações , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo , Proteínas tau/metabolismo
16.
Sci Rep ; 7(1): 8795, 2017 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-28821831

RESUMO

The receptor for advanced glycation endproducts (RAGE) is a pattern-recognition receptor associated with inflammation in most cell types. RAGE up-regulates the expression of proinflammatory mediators and its own expression via activation of NF-kB. Recent works have proposed a role for RAGE in Parkinson's disease (PD). In this study, we used the multimodal blocker of RAGE FPS-ZM1, which has become available recently, to selectively inhibit RAGE in the substantia nigra (SN) of rats intracranially injected with 6-hydroxydopamine (6-OHDA). FPS-ZM1 (40 µg per rat), injected concomitantly with 6-OHDA (10 µg per rat) into the SN, inhibited the increase in RAGE, activation of ERK1/2, Src and nuclear translocation of NF-kB p65 subunit in the SN. RAGE inhibition blocked glial fibrillary acidic protein and Iba-1 upregulation as well as associated astrocyte and microglia activation. Circulating cytokines in serum and CSF were also decreased by FPS-ZM1 injection. The loss of tyrosine hydroxylase and NeuN-positive neurons was significantly inhibited by RAGE blocking. Finally, FPS-ZM1 attenuated locomotory and exploratory deficits induced by 6-OHDA. Our results demonstrate that RAGE is an essential component in the neuroinflammation and dopaminergic denervation induced by 6-OHDA in the SN. Selective inhibition of RAGE may offer perspectives for therapeutic approaches.


Assuntos
Dopamina/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Oxidopamina/efeitos adversos , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidores , Substância Negra/metabolismo , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Neurônios Dopaminérgicos/patologia , Mediadores da Inflamação/metabolismo , Masculino , NF-kappa B/metabolismo , Doença de Parkinson/etiologia , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Ratos , Substância Negra/efeitos dos fármacos , Substância Negra/patologia , Quinases da Família src/metabolismo
17.
Cell Physiol Biochem ; 42(6): 2507-2522, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28848092

RESUMO

BACKGROUND/AIMS: Heat shock protein 70 (HSP70) has been recently described with extracellular actions, where it is actively released in inflammatory conditions. Acting as DAMPs (damage associated molecular pattern), extracellular HSP70 (eHSP70) interacts with membrane receptors and activates inflammatory pathways. At this context, the receptor for advanced glycation endproducts (RAGE) emerges as a possible candidate for interaction with eHSP70. RAGE is a pattern-recognition receptor and its expression is increased in several diseases related to a chronic pro-inflammatory state. One of the main consequences of RAGE ligand-binding is the ERK1/2 (extracellular signal-regulated kinases)-dependent activation of NF-kB (nuclear factor kappa B), which leads to expression of TNF-α (tumor necrosis factor alpha) and other cytokines. The purpose of this work is to elucidate if eHSP70 is able to evoke RAGE-dependent signaling using A549 human lung cancer cells, which constitutively express RAGE. METHODS: Immunoprecipitation and protein proximity assay were utilized to demonstrate the linkage between RAGE and eHSP70. To investigate RAGE relevance on cell response to eHSP70, siRNA was used to knockdown the receptor expression. Signaling pathways activation were evaluated by western blotting, gene reporter luciferase and real time quantitative PCR. RESULTS: Protein eHSP70 shown to be interacting physically with the receptor RAGE in our cell model. Treatment with eHSP70 caused ERK1/2 activation and NF-κB transactivation impaired by RAGE knockdown. Moreover, the stimulation of pro-inflammatory cytokines expression by eHSP70 was inhibited in RAGE-silenced cells. Finally, conditioned medium of eHSP70-treated A549 cells caused differential effects in monocytes cytokine expression when A549 RAGE expression is inhibited. CONCLUSIONS: Our results evidence eHSP70 as a novel RAGE agonist capable of influence the cross-talk between cancer and immune system cells.


Assuntos
Proteínas de Choque Térmico HSP70/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , NF-kappa B/metabolismo , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Células A549 , Citocinas/genética , Citocinas/metabolismo , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/farmacologia , Humanos , Immunoblotting , Imunoprecipitação , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , NF-kappa B/genética , Fosforilação , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidores , Receptor para Produtos Finais de Glicação Avançada/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/farmacologia , Transdução de Sinais/efeitos dos fármacos , Ativação Transcricional , Células U937
18.
Appl Physiol Nutr Metab ; 42(11): 1192-1200, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28742973

RESUMO

The use of dietary supplements to enhance the benefit of exercise training is a common practice. The liver is the organ where all substances are metabolized, and certain supplements have been associated with liver injury. Vitamin A (VA), a liposoluble vitamin stored in the liver, is commonly used as an antioxidant supplement. Here, we evaluated the effect of chronic VA supplementation on oxidative damage and stress parameters in trained rats. Animals were divided into the following groups: sedentary (SE), sedentary/VA (SE+VA), exercise training (ET), and exercise training/VA (ET+VA). During 8 weeks, animals were subjected to swimming (0%, 2%, 4%, 6% body weight) for 5 days/week and a VA daily intake of 450 retinol equivalents/day. Parameters were evaluated by enzymatic activity analysis, ELISA, and Western blotting. VA caused liver lipid peroxidation and protein damage in exercised rats and inhibited the increase in HSP70 expression acquired with exercise alone. The ET group showed higher levels of antioxidant enzyme activity, and VA inhibited this adaptation. Expression of the pro-inflammatory cytokines, interleukin (IL)-1ß, and tumor necrosis factor-α was reduced in the ET+VA group, while the anti-inflammatory cytokine, IL-10, was increased. Western blotting showed that both exercised groups had lower levels of the receptor for advanced glycation end products, suggesting that VA did not affect this receptor. Our study demonstrated that, although VA caused oxidative damage, a controlled administration might exert anti-inflammatory effects. Further studies with higher VA doses and longer ET interventions would elucidate more the effects of the supplementation and exercise on liver parameters.


Assuntos
Suplementos Nutricionais , Fígado/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Condicionamento Físico Animal , Vitamina A/administração & dosagem , Administração Oral , Alanina Transaminase/sangue , Animais , Antioxidantes , Aspartato Aminotransferases/sangue , Citocinas/sangue , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Masculino , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/sangue , Natação , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
19.
Neurochem Res ; 42(10): 2788-2797, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28497345

RESUMO

Retinoids (vitamin A and derivatives) are recognized as essential factors for central nervous system (CNS) development. Retinol (vitamin A) also was postulated to be a major antioxidant component of diet as it modulates reactive species (RS) production and oxidative stress in biological systems. Oxidative stress plays a major role either in pathogenesis or development of neurodegenerative diseases, or even in both. Here we investigate the role of retinol supplementation to human neuron-derived SH-SY5Y cells over RS production and biochemical markers associated to neurodegenerative diseases expressed at neuronal level in Parkinson's disease and Alzheimer's disease: α-synuclein, ß-amyloid peptide, tau phosphorylation and RAGE. Retinol treatment (24 h) impaired cell viability and increased intracellular RS production at the highest concentrations (7 up to 20 µM). Antioxidant co-treatment (Trolox 100 µM) rescued cell viability and inhibited RS production. Furthermore, retinol (10 µM) increased the levels of α-synuclein, tau phosphorylation at Ser396, ß-amyloid peptide and RAGE. Co-treatment with antioxidant Trolox inhibited the increased in RAGE, but not the effect of retinol on α-synuclein, tau phosphorylation and ß-amyloid peptide accumulation. These data indicate that increased availability of retinol to neurons at levels above the cellular physiological concentrations may induce deleterious effects through diverse mechanisms, which include oxidative stress but also include RS-independent modulation of proteins associated to progression of neuronal cell death during the course of neurodegenerative diseases.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Vitamina A/farmacologia , alfa-Sinucleína/metabolismo , Proteínas tau/metabolismo , Antioxidantes/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Neurônios/metabolismo , Fosforilação , Vitamina A/metabolismo
20.
Nutrients ; 9(4)2017 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-28368329

RESUMO

Exercise training intensity is the major variant that influences the relationship between exercise, redox balance, and immune response. Supplement intake is a common practice for oxidative stress prevention; the effects of vitamin A (VA) on exercise training are not yet described, even though this molecule exhibits antioxidant properties. We investigated the role of VA supplementation on redox and immune responses of adult Wistar rats subjected to swimming training. Animals were divided into four groups: sedentary, sedentary + VA, exercise training, and exercise training + VA. Over eight weeks, animals were submitted to intense swimming 5 times/week and a VA daily intake of 450 retinol equivalents/day. VA impaired the total serum antioxidant capacity acquired by exercise, with no change in interleukin-1ß and tumor necrosis factor-α levels. In skeletal muscle, VA caused lipid peroxidation and protein damage without differences in antioxidant enzyme activities; however, Western blot analysis showed that expression of superoxide dismutase-1 was downregulated, and upregulation of superoxide dismutase-2 induced by exercise was blunted by VA. Furthermore, VA supplementation decreased anti-inflammatory interleukin-10 and heat shock protein 70 expression, important factors for positive exercise adaptations and tissue damage prevention. Our data showed that VA supplementation did not confer any antioxidative and/or protective effects, attenuating exercise-acquired benefits in the skeletal muscle.


Assuntos
Suplementos Nutricionais/efeitos adversos , Proteínas de Choque Térmico HSP70/antagonistas & inibidores , Interleucina-10/antagonistas & inibidores , Músculo Esquelético/metabolismo , Miosite/etiologia , Estresse Oxidativo , Vitamina A/efeitos adversos , Animais , Biomarcadores/sangue , Biomarcadores/metabolismo , Western Blotting , Proteínas de Choque Térmico HSP70/metabolismo , Mediadores da Inflamação/sangue , Mediadores da Inflamação/metabolismo , Interleucina-10/metabolismo , Peroxidação de Lipídeos , Masculino , Músculo Esquelético/enzimologia , Músculo Esquelético/imunologia , Miosite/sangue , Miosite/imunologia , Miosite/metabolismo , Oxirredutases/antagonistas & inibidores , Oxirredutases/química , Oxirredutases/metabolismo , Capacidade de Absorbância de Radicais de Oxigênio , Condicionamento Físico Animal/efeitos adversos , Distribuição Aleatória , Ratos Wistar
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA