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1.
Ecotoxicol Environ Saf ; 279: 116464, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38759534

RESUMO

1,2-Dichloroethane (1,2-DCE) is a powerfully toxic neurotoxin, which is a common environmental pollutant. Studies have indicated that 1,2-DCE long-term exposure can result in adverse effects. Nevertheless, the precise mechanism remains unknown. In this study, behavioral results revealed that 1,2-DCE long-term exposure could cause anxiety and learning and memory ability impairment in mice. The contents of γ-aminobutyric acid (GABA) and glutamine (Gln) in mice's prefrontal cortex decreased, whereas that of glutamate (Glu) increased. With the increase in dose, the activities of glutamate decarboxylase (GAD) decreased and those of GABA transaminase (GABA-T) increased. The protein and mRNA expressions of GABA transporter-3 (GAT-3), vesicular GABA transporter (VGAT), GABA A receptor α2 (GABAARα2), GABAARγ2, K-Cl cotransporter isoform 2 (KCC2), GABA B receptor 1 (GABABR1), GABABR2, protein kinase A (PKA), cAMP-response element binding protein (CREB), p-CREB, brain-derived neurotrophic factor (BDNF), c-fos, c-Jun and the protein of glutamate dehydrogenase (GDH) and PKA-C were decreased, while the expression levels of GABA transporter-1 (GAT-1) and Na-K-2Cl cotransporter isoform 1 (NKCC1) were increased. However, there was no significant change in the protein content of succinic semialdehyde dehydrogenase (SSADH). The expressions of adenylate cyclase (AC) and cyclic adenosine monophosphate (cAMP) contents were also reduced. In conclusion, the results of this study show that exposure to 1,2-DCE could lead to anxiety and cognitive impairment in mice, which may be related to the disturbance of GABA metabolism and its receptors along with the cAMP-PKA-CREB pathway.


Assuntos
Ansiedade , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Proteínas Quinases Dependentes de AMP Cíclico , Dicloretos de Etileno , Transdução de Sinais , Ácido gama-Aminobutírico , Animais , Camundongos , Ácido gama-Aminobutírico/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Dicloretos de Etileno/toxicidade , Masculino , Ansiedade/induzido quimicamente , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/metabolismo , AMP Cíclico/metabolismo , Poluentes Ambientais/toxicidade , Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Glutamato Descarboxilase/metabolismo
2.
Neurochem Int ; 165: 105522, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36966820

RESUMO

The GABA transporter GAT1 regulates brain inhibitory neurotransmission and it is considered a potential therapeutic target for the treatment of wide spectrum of neurological diseases including epilepsy, stroke and autism. Syntenin-1 binds to syntaxin 1A, which is known to regulate the plasma membrane insertion of several neurotransmitter transporters. Previously, a direct interaction of syntenin-1 with the glycine transporter GlyT2 was reported. Here, we show that the GABA transporter GAT1 also directly interacts with syntenin-1, involving both unidentified protein interaction interface and the GAT1 C-terminal PDZ binding motif interacting mainly with syntenin-1 PDZ domain 1. The PDZ interaction was eliminated by the mutation of GAT1 isoleucine 599 and tyrosine 598 located in PDZ positions 0 and -1, respectively. This indicates an unconventional PDZ interaction and possible regulation of the transporter PDZ motif via tyrosine phosphorylation. Whole syntenin-1 protein fused to GST protein and immobilised on glutathione resin coprecipitated intact GAT1 transporter from an extract of GAT1 transfected neuroblastoma N2a cells. This coprecipitation was inhibited by tyrosine phosphatases inhibitor pervanadate. The fluorescence tagged GAT1 and syntenin-1 colocalized upon coexpression in N2a cells. The above results show that syntenin-1 might be, in addition to GlyT2, directly involved in the trafficking of GAT1 transporter.


Assuntos
Proteínas da Membrana Plasmática de Transporte de GABA , Proteínas do Tecido Nervoso , Sinteninas , Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Ligação Proteica , Sinteninas/genética , Sinteninas/metabolismo , Tirosina/metabolismo , Animais , Camundongos , Linhagem Celular
3.
J Proteome Res ; 20(11): 5054-5063, 2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34647753

RESUMO

The classic neurotransmitter γ-aminobutyric acid (GABA) has been shown to shape the activation and function of immune cells. There are four high-affinity GABA transporters (GATs, including GAT-1, GAT-2, GAT-3, and GAT-4) responsible for the transmembrane transport of GABA in mice. To explore the effect of GAT-2 on type 1 helper T (Th1) cells, naïve CD4+ T cells were isolated from splenocytes of GAT-2 knockout (KO) and wild-type (WT) mice and cultured for Th1 cell differentiation, and then, metabolomics analysis of Th1 cells was performed via gas chromatography coupled to time-of-flight mass spectrometry added with multivariate analyses. Based on the variable importance projection value > 1 and P < 0.05, a total of nine differentially expressed metabolites (DEMs) were identified between WT and KO. Then, DEMs were mapped to the KEGG database, and five metabolic pathways were significantly enriched, including the cysteine and methionine metabolism, the riboflavin metabolism, the purine metabolism, the glycerolipid metabolism, and the glycerophospholipid metabolism. Collectively, our metabolomics analysis revealed that deficiency of GAT-2 influenced the metabolomics profile of Th1 cells, which will provide insights into T cell response to GAT-2 deficiency in mice. Data are available via MetaboLights with identifier MTBLS3358.


Assuntos
Metabolômica , Células Th1 , Animais , Proteínas da Membrana Plasmática de Transporte de GABA/genética , Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Camundongos , Polímeros , Células Th1/metabolismo
4.
Sci Adv ; 7(15)2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33827820

RESUMO

Accumulating evidence shows that nervous system governs host immune responses; however, how γ-aminobutyric acid (GABA)ergic system shapes the function of innate immune cells is poorly defined. Here, we demonstrate that GABA transporter (GAT2) modulates the macrophage function. GAT2 deficiency lowers the production of interleukin-1ß (IL-1ß) in proinflammatory macrophages. Mechanistically, GAT2 deficiency boosts the betaine/S-adenosylmethionine (SAM)/hypoxanthine metabolic pathway to inhibit transcription factor KID3 expression through the increased DNA methylation in its promoter region. KID3 regulates oxidative phosphorylation (OXPHOS) via targeting the expression of OXPHOS-related genes and is also critical for NLRP3-ASC-caspase-1 complex formation. Likewise, GAT2 deficiency attenuates macrophage-mediated inflammatory responses in vivo, including lipopolysaccharide-induced sepsis, infection-induced pneumonia, and high-fat diet-induced obesity. Together, we propose that targeting GABAergic system (e.g., GABA transporter) could provide previously unidentified therapeutic opportunities for the macrophage-associated diseases.


Assuntos
Lipopolissacarídeos , Macrófagos , Caspases/metabolismo , Proteínas da Membrana Plasmática de Transporte de GABA/genética , Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Expressão Gênica , Interleucina-1beta/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo
5.
J Bacteriol ; 203(4)2021 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-33288625

RESUMO

Characterizing the mycobacterial transporters involved in the uptake and/or catabolism of host-derived nutrients required by mycobacteria may identify novel drug targets against tuberculosis. Here, we identify and characterize a member of the amino acid-polyamine-organocation superfamily, a potential γ-aminobutyric acid (GABA) transport protein, GabP, from Mycobacterium smegmatis The protein was expressed to a level allowing its purification to homogeneity, and size exclusion chromatography coupled with multiangle laser light scattering (SEC-MALLS) analysis of the purified protein showed that it was dimeric. We showed that GabP transported γ-aminobutyric acid both in vitro and when overexpressed in E. coli Additionally, transport was greatly reduced in the presence of ß-alanine, suggesting it could be either a substrate or inhibitor of GabP. Using GabP reconstituted into proteoliposomes, we demonstrated that γ-aminobutyric acid uptake is driven by the sodium gradient and is stimulated by membrane potential. Molecular docking showed that γ-aminobutyric acid binds MsGabP, another Mycobacterium smegmatis putative GabP, and the Mycobacterium tuberculosis homologue in the same manner. This study represents the first expression, purification, and characterization of an active γ-aminobutyric acid transport protein from mycobacteria.IMPORTANCE The spread of multidrug-resistant tuberculosis increases its global health impact in humans. As there is transmission both to and from animals, the spread of the disease also increases its effects in a broad range of animal species. Identifying new mycobacterial transporters will enhance our understanding of mycobacterial physiology and, furthermore, provides new drug targets. Our target protein is the gene product of msmeg_6196, annotated as GABA permease, from Mycobacterium smegmatis strain MC2 155. Our current study demonstrates it is a sodium-dependent GABA transporter that may also transport ß-alanine. As GABA may well be an essential nutrient for mycobacterial metabolism inside the host, this could be an attractive target for the development of new drugs against tuberculosis.


Assuntos
Proteínas de Bactérias/metabolismo , Transporte Biológico/fisiologia , Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Mycobacterium smegmatis/metabolismo , Transportadores de Ânions Orgânicos/metabolismo , Sódio/metabolismo , Ácido gama-Aminobutírico/metabolismo , Proteínas de Bactérias/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli , Proteínas da Membrana Plasmática de Transporte de GABA/genética , Regulação Bacteriana da Expressão Gênica , Metabolômica , Simulação de Acoplamento Molecular , Transportadores de Ânions Orgânicos/genética , Filogenia , Ácido gama-Aminobutírico/química , Ácido gama-Aminobutírico/genética
6.
Plant Cell Environ ; 43(10): 2443-2459, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32666573

RESUMO

Malate exudation through wheat (Triticum aestivum L) aluminium-activated malate transporter 1 (TaALMT1) confers Al3+ tolerance at low pH, but is also activated by alkaline pH, and is regulated by and facilitates significant transport of gamma-aminobutyric acid (GABA, a zwitterionic buffer). Therefore, TaALMT1 may facilitate acidification of an alkaline rhizosphere by promoting exudation of both malate and GABA. Here, the performance of wheat near isogenic lines ET8 (Al+3 -tolerant, high TaALMT1 expression) and ES8 (Al+3 -sensitive, low TaALMT1 expression) are compared. Root growth (at 5 weeks) was higher for ET8 than ES8 at pH 9. ET8 roots exuded more malate and GABA at high pH and acidified the rhizosphere more rapidly. GABA and malate exudation was enhanced at high pH by the addition of aluminate in both ET8 and transgenic barley expressing TaALMT1. Xenopus laevis oocytes expressing TaALMT1 acidified an alkaline media more rapidly than controls corresponding to higher GABA efflux. TaALMT1 expression did not change under alkaline conditions but key genes involved in GABA turnover changed in accordance with a high rate of GABA synthesis. We propose that TaALMT1 plays a role in alkaline tolerance by exuding malate and GABA, possibly coupled to proton efflux.


Assuntos
Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Malatos/metabolismo , Transportadores de Ânions Orgânicos/metabolismo , Proteínas de Plantas/metabolismo , Triticum/metabolismo , Ácido gama-Aminobutírico/metabolismo , Animais , Animais Geneticamente Modificados , Clorofila/metabolismo , Proteínas da Membrana Plasmática de Transporte de GABA/fisiologia , Hordeum , Concentração de Íons de Hidrogênio , Oócitos , Transportadores de Ânions Orgânicos/fisiologia , Folhas de Planta/metabolismo , Proteínas de Plantas/fisiologia , Raízes de Plantas/metabolismo , Raízes de Plantas/fisiologia , Plantas Geneticamente Modificadas , Rizosfera , Plântula/metabolismo , Plântula/fisiologia , Estresse Fisiológico , Triticum/fisiologia , Xenopus
7.
Artigo em Inglês | MEDLINE | ID: mdl-32660967

RESUMO

SLC6A1 is associated with an autosomal dominant early-onset seizure and epileptic encephalopathy associated with intellectual disability. We present a 2-yr-old girl with developmental delay and epilepsy, using a new computational filtering impact score to show the patient's variant ranks with other pathogenic variants. Genomic studies within the patient revealed a G443D variant of uncertain significance. Structural and evolutionary assessments establish this variant as a loss of function to the protein. Compiled metrics through our custom tools on sequence, structure, and protein dynamics combined with PolyPhen-2, PROVEAN, SIFT, and Align-GVGD reveal this variant to rank in the top functional outcome changes relative to gnomAD, TOPMed, and ClinVar variants known to date. The patient was resistant to multiple epileptic drugs, finally finding that valproic acid controls the seizures. This is consistent with additional groups studying SLC6A1 variants within patients.


Assuntos
Deficiências do Desenvolvimento/genética , Epilepsia/genética , Proteínas da Membrana Plasmática de Transporte de GABA/genética , Pré-Escolar , Feminino , Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Predisposição Genética para Doença/genética , Humanos , Deficiência Intelectual/genética , Mutação com Perda de Função/genética , Mutação/genética , Fenótipo , Convulsões/genética , Ácido Valproico/farmacologia
8.
BMC Cancer ; 20(1): 289, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32252682

RESUMO

BACKGROUND: Solute Carrier Family 6 Member 1 (SLC6A1) has been identified as a cancer-promoting gene in various human cancers, such as clear cell renal cell carcinoma and ovarian cancer. However, its roles in prostate cancer (PCa) has not been fully elucidated. The aim of this study was to investigate the expression and clinical significance of SLC6A1 in PCa tissues and its effect on drug resistance to docetaxel in PCa. METHODS: Expression patterns of SLC6A1 protein in PCa tissues were examined by immunohistochemistry based on Tissue microarray. Associations of SLC6A1 protein expression with various clinicopathological features and patients' prognosis of PCa were also statistically evaluated based on TCGA data. Roles of SLC6A1 deregulation in prostate carcinogenesis and drug resistance was further determined in vitro and in vivo experiments. RESULTS: Based on TCGA Dataset, SLC6A1 expression was markedly higher in patients with high Gleason score, advanced clinical stage and positive biochemical recurrence than those with control features (all P < 0.05). Both unvariate and multivariate analyses demonstrated that SLC6A1 expression was significantly associated with biochemical recurrence-free survival in PCa patients. In addition, enforced expression of SLC6A1 effectively promoted cell proliferation, migration and invasion of PCa cells in vitro. Moreover, the inhibition of SLC6A1 suppressed the tumor growth in vivo. Additionally, immunohistochemical notches of PCNA and MMP-9 in the low-expression cluster were pointedly lower compared to those of NC group. Finally, the cell viability revealed that the overexpression of SLC6A1 obviously promoted the PCa cell resistant to docetaxel (DTX), and the transplanted tumor in the overexpression group had no significant reduction compared with the untreated group. CONCLUSIONS: Our data suggest that SLC6A1 overexpression may be associated with aggressive progression and short biochemical recurrence-free survival of PCa, and may be related to the resistance to docetaxel therapy.


Assuntos
Biomarcadores Tumorais/metabolismo , Docetaxel/farmacologia , Resistencia a Medicamentos Antineoplásicos , Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias da Próstata/patologia , Idoso , Animais , Antineoplásicos/farmacologia , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Proliferação de Células , Biologia Computacional/métodos , Bases de Dados Genéticas/estatística & dados numéricos , Progressão da Doença , Proteínas da Membrana Plasmática de Transporte de GABA/genética , Humanos , Masculino , Camundongos , Camundongos Nus , Prognóstico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Taxa de Sobrevida , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Front Biosci (Landmark Ed) ; 25(7): 1386-1411, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-32114438

RESUMO

Accumulation of osmolytes, during cell volume perturbations, as cell volume regulators is ensured through their de novo synthesis, decreased degradation and transport from their site of synthesis to the site of utility through various transport systems. Among these, transport system mediated accumulation has been observed to be quite significant during long term cell volume perturbation. Under stress conditions, these osmolyte transporters are regulated at transcriptional as well as translational level. At translational level, protein kinases carry out phosphorylation of osmolyte transporters and have been shown to play a crucial role in cell volume homeostasis. In fact phosphorylation of osmolyte transporters on their conserved residues regulates the uptake and efflux of osmolytes by cells. Additionally, accumulated osmolytes in turn have been shown to modulate the structure and functioning of protein kinases. The present review has tried to provide an overview about the role of protein kinases in regulation of osmolyte accumulation under stress conditions. Due to their ability of regulating osmolyte accumulation, potential of protein kinases as therapeutic targets for diseases like cancer has also been highlighted.


Assuntos
Tamanho Celular , Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Pressão Osmótica/fisiologia , Proteínas Quinases/metabolismo , Estresse Fisiológico/fisiologia , Betaína/metabolismo , Humanos , Concentração Osmolar , Taurina/metabolismo
10.
Cell Rep ; 30(12): 4303-4316.e6, 2020 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-32209486

RESUMO

Mice engineered for conditional, cell type-specific gene inactivation have dominated the field of mouse genetics because of the high efficiency of Cre-loxP-mediated recombination. Recent advances in CRISPR/Cas9 technologies have provided alternatives for rapid gene mutagenesis for loss-of-function (LOF) analysis. Whether these strategies can be streamlined for rapid genetic analysis with the efficiencies comparable with those of conventional genetic approaches has yet to be established. We show that a single adeno-associated viral (AAV) vector containing a recombinase-dependent Staphylococcus aureus Cas9 (SaCas9) and a single guide RNA (sgRNA) are as efficient as conventional conditional gene knockout and can be adapted for use in either Cre- or Flp-driver mouse lines. The efficacy of this approach is demonstrated for the analysis of GABAergic, glutamatergic, and monoaminergic neurotransmission. Using this strategy, we reveal insight into the role of GABAergic regulation of midbrain GABA-producing neurons in psychomotor activation.


Assuntos
Envelhecimento/genética , Proteína 9 Associada à CRISPR/metabolismo , Sistemas CRISPR-Cas/genética , Dependovirus/genética , Vetores Genéticos/metabolismo , Mutagênese/genética , Sistema Nervoso/metabolismo , Animais , Sequência de Bases , Linhagem Celular , DNA Nucleotidiltransferases/metabolismo , Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Ácido Glutâmico/metabolismo , Camundongos Endogâmicos C57BL , Mutação/genética , Optogenética , Fenótipo
11.
Neurochem Int ; 131: 104550, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31563462

RESUMO

Caffeine is the most consumed psychostimulant drug in the world, acting as a non-selective antagonist of adenosine receptors A1R and A2AR, which are widely expressed in retinal layers. We have previously shown that caffeine, when administered acutely, acts on A1R to potentiate the NMDA receptor-induced GABA release. Now we asked if long-term caffeine exposure also modifies GABA uptake in the avian retina and which mechanisms are involved in this process. Chicken embryos aged E11 were injected with a single dose of caffeine (30 mg/kg) in the air chamber. Retinas were dissected on E15 for ex vivo neurochemical assays. Our results showed that [3H]-GABA uptake was dependent on Na+ and blocked at 4 °C or by NO-711 and caffeine. This decrease was observed after 60 min of [3H]-GABA uptake assay at E15, which is accompanied by an increase in [3H]-GABA release. Caffeine increased the protein levels of A1R without altering ADORA1 mRNA and was devoid of effects on A2AR density or ADORA2A mRNA levels. The decrease of GABA uptake promoted by caffeine was reverted by A1R activation with N6-cyclohexyl adenosine (CHA) but not by A2AR activation with CGS 21680. Caffeine exposure increased cAMP levels and GAT-1 protein levels, which was evenly expressed between E11-E15. As expected, we observed an increase of GABA containing amacrine cells and processes in the IPL, also, cAMP pathway blockage by H-89 decreased caffeine mediated [3H]-GABA uptake. Our data support the idea that chronic injection of caffeine alters GABA transport via A1R during retinal development and that the cAMP/PKA pathway plays an important role in the regulation of GAT-1 function.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Antagonistas de Receptores de Angiotensina/farmacologia , Cafeína/farmacologia , Estimulantes do Sistema Nervoso Central/farmacologia , AMP Cíclico/fisiologia , Ácido gama-Aminobutírico/metabolismo , Adenosina/análogos & derivados , Adenosina/farmacologia , Células Amácrinas/efeitos dos fármacos , Células Amácrinas/metabolismo , Animais , Cafeína/antagonistas & inibidores , Embrião de Galinha , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Fenetilaminas/farmacologia , Receptor A1 de Adenosina/efeitos dos fármacos , Receptor A1 de Adenosina/metabolismo , Receptor Tipo 1 de Angiotensina/efeitos dos fármacos , Receptores A2 de Adenosina/efeitos dos fármacos , Receptores A2 de Adenosina/metabolismo , Retina/efeitos dos fármacos , Retina/embriologia , Retina/crescimento & desenvolvimento , Transdução de Sinais/efeitos dos fármacos
12.
Eur J Pharmacol ; 858: 172475, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31228456

RESUMO

The development of effective therapeutics for cancer-induced bone pain (CIBP) remains a tremendous challenge owing to its unclear mechanisms. Gamma-aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the central nervous system (CNS). Emerging studies have shown that disinhibition in the spinal cord dorsal horn may account for the development of chronic pain. However, the role of GABA in the development of CIBP remains elusive. In addition, accumulating evidence has shown that neuroglial cells in the peripheral nervous system, especially astrocytes and microglial cells, played an important role in the maintenance of CIBP. In this study, we investigated the expression of GABA and Gamma-aminobutyric acid transporter-1 (GAT-1), a transporter of GABA. Our results demonstrate that GABA was decreased in CIBP rats as expected. However, the expression of glutamic acid decarboxylase (GAD) 65 was up-regulated on day 21 after surgery, while the expression of GAD 67 remained unchanged after surgery. We also found that the expression of GAT-1 was up-regulated mainly in the astrocytes of the spinal cord. Moreover, we evaluated the analgesic effect of exogenous GABA and the GAT-1 inhibitor. Intrathecal administration of exogenous GABA and NO-711 (a GAT-1 selective inhibitor) significantly reversed CIBP-induced mechanical allodynia in a dose-dependent manner. These results firstly show that neuron-glia interactions, especially on the GABAergic pathway, contribute to the development of CIBP. In conclusion, exogenous GABA and GAT-1 inhibitor might be alternative therapeutic strategies for the treatment of CIBP.


Assuntos
Neoplasias Ósseas/complicações , Dor do Câncer/tratamento farmacológico , Dor do Câncer/patologia , Comunicação Celular/efeitos dos fármacos , Neuroglia/patologia , Neurônios/patologia , Ácido gama-Aminobutírico/farmacologia , Animais , Neoplasias Ósseas/secundário , Dor do Câncer/etiologia , Linhagem Celular Tumoral , Feminino , Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Glutamato Descarboxilase/metabolismo , Hiperalgesia/tratamento farmacológico , Neuroglia/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Ácido gama-Aminobutírico/metabolismo , Ácido gama-Aminobutírico/uso terapêutico
13.
Environ Microbiol ; 21(7): 2559-2575, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31090982

RESUMO

Marine bacterioplankton face stiff competition for limited nutrient resources. SAR11, a ubiquitous clade of very small and highly abundant Alphaproteobacteria, are known to devote much of their energy to synthesizing ATP-binding cassette periplasmic proteins that bind substrates. We hypothesized that their small size and relatively large periplasmic space might enable them to outcompete other bacterioplankton for nutrients. Using uptake experiments with 14 C-glycine betaine, we discovered that two strains of SAR11, Candidatus Pelagibacter sp. HTCC7211 and Cand. P. ubique HTCC1062, have extraordinarily high affinity for glycine betaine (GBT), with half-saturation (K s ) values around 1 nM and specific affinity values between 8 and 14 L mg cell-1 h-1 . Competitive inhibition studies indicated that the GBT transporters in these strains are multifunctional, transporting multiple substrates in addition to GBT. Both strains could use most of the transported compounds for metabolism and ATP production. Our findings indicate that Pelagibacter cells are primarily responsible for the high affinity and multifunctional GBT uptake systems observed in seawater. Maximization of whole-cell affinities may enable these organisms to compete effectively for nutrients during periods when the gross transport capacity of the heterotrophic plankton community exceeds the supply, depressing ambient concentrations.


Assuntos
Alphaproteobacteria/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Alphaproteobacteria/classificação , Alphaproteobacteria/genética , Proteínas de Bactérias/genética , Betaína/metabolismo , Proteínas da Membrana Plasmática de Transporte de GABA/genética , Glicina/metabolismo , Plâncton/genética , Plâncton/metabolismo , Água do Mar/microbiologia
14.
J Cell Mol Med ; 23(8): 5017-5024, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31144434

RESUMO

In the central nervous system, interleukin (IL)-1ß, IL-6 and tumour necrosis factor (TNF)-α have a regulatory role in pathophysiological processes of epilepsy. In addition, γ-aminobutyric acid (GABA) transporter type 1 and type 3 (GAT-1 and GAT-3) modulate the levels of extracellular GABA in involvement in the neuroinflammation on epileptogenesis. Thus, in the current report we examined the effects of inhibiting microRNA-155 (miR-155) on the levels of IL-1ß, IL-6 and TNF-α, and expression of GAT-1 and GAT-3 in the parietal cortex, hippocampus and amygdala of rats with nonconvulsive seizure (NCS) following cerebral ischaemia. Real time RT-PCR, ELISA and Western blot analysis were used to examine the miR-155, proinflammatory cytokines (PICs) and GAT-1/GAT-3 respectively. With induction of NCS, the levels of miR-155 were amplified in the parietal cortex, hippocampus and amygdala and this was accompanied with increases of IL-1ß, IL-6 and TNF-α. In those central areas, expression of GAT-1 and GAT-3 was upregulated; and GABA was reduced in rats following NCS. Intracerebroventricular infusion of miR-155 inhibitor attenuated the elevation of PICs, amplification of GAT-1 and GAT-3 and impairment of GABA. Furthermore, inhibition of miR-155 decreased the number of NCS events following cerebral ischaemia. Inhibition of miR-155 further improved post-ischaemia-evoked NCS by altering neuroinflammation-GABA signal pathways in the parietal cortex, hippocampus and amygdala. Results suggest the role of miR-155 in regulating post-ischaemic seizures via PICs-GABA mechanisms.


Assuntos
Tonsila do Cerebelo/metabolismo , Isquemia Encefálica/metabolismo , Hipocampo/metabolismo , MicroRNAs/metabolismo , Lobo Parietal/metabolismo , Convulsões/metabolismo , Ácido gama-Aminobutírico/metabolismo , Animais , Isquemia Encefálica/genética , Modelos Animais de Doenças , Epilepsia/metabolismo , Proteínas da Membrana Plasmática de Transporte de GABA/genética , Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Infarto da Artéria Cerebral Média/fisiopatologia , Inflamação/genética , Inflamação/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Masculino , MicroRNAs/genética , Lobo Parietal/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Convulsões/genética , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
15.
Neurosci Bull ; 35(4): 637-648, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30790216

RESUMO

Activation of inflammatory responses regulates the transmission of pain pathways through an integrated network in the peripheral and central nervous systems. The immunopotentiator thymosin alpha-1 (Tα1) has recently been reported to have anti-inflammatory and neuroprotective functions in rodents. However, how Tα1 affects inflammatory pain remains unclear. In the present study, intraperitoneal injection of Tα1 attenuated complete Freund's adjuvant (CFA)-induced pain hypersensitivity, and decreased the up-regulation of pro-inflammatory cytokines (TNF-α, IL-1ß, and IL-6) in inflamed skin and the spinal cord. We found that CFA-induced peripheral inflammation evoked strong microglial activation, but the effect was reversed by Tα1. Notably, Tα1 reversed the CFA-induced up-regulation of vesicular glutamate transporter (VGLUT) and down-regulated the vesicular γ-aminobutyric acid transporter (VGAT) in the spinal cord. Taken together, these results suggest that Tα1 plays a therapeutic role in inflammatory pain and in the modulation of microglia-induced pro-inflammatory cytokine production in addition to mediation of VGLUT and VGAT expression in the spinal cord.


Assuntos
Citocinas/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Dor/tratamento farmacológico , Dor/metabolismo , Timalfasina/farmacologia , Sistema X-AG de Transporte de Aminoácidos/metabolismo , Animais , Adjuvante de Freund , Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Hiperalgesia/tratamento farmacológico , Hiperalgesia/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microglia/metabolismo , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
16.
Eur J Pharmacol ; 842: 57-63, 2019 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-30393201

RESUMO

In the pathophysiology of Alzheimer's disease (AD), the deposition of amyloid ß protein (Aß) is associated with oxidative stress, leading to cognitive impairment and neurodegeneration. Betaine (glycine betaine or trimethylglycine), known as an osmolyte and methyl donor in mammalian cells, has been reported to suppress the proinflammatory response and oxidative stress in the kidneys, but the effects of betaine on brain diseases remain to be determined. Here, to investigate the effects of betaine treatment on cognitive impairment and the increase in oxidative stress in the brain of an AD animal model, we performed a novel object recognition test and measured the malondialdehyde (MDA; a marker of oxidative stress) levels in the frontal cortex and hippocampus of mice intracerebroventricularly injected with Aß25-35, an active fragment of Aß. Betaine prevented cognitive impairment as well as increases of the cortical and hippocampal MDA levels in Aß25-35-injected mice. Of note, NNC 05-2090, a selective inhibitor of betaine/GABA transporter-1 (GAT2/BGT-1), reduced the preventive effects of betaine on Aß25-35-induced cognitive impairment without affecting the increased MDA levels in the brain of Aß25-35-injected mice. As betaine is used as a substrate of GAT2/BGT-1, these results suggest that betaine is transported through GAT2/BGT-1 and prevents cognitive impairment in Aß25-35-injected mice, but GAT2/BGT-1 function is not required for the antioxidant effects of betaine.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Betaína/farmacologia , Encéfalo/metabolismo , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/prevenção & controle , Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fragmentos de Peptídeos/toxicidade , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/fisiopatologia , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/fisiopatologia , Injeções , Masculino , Malondialdeído/metabolismo , Camundongos , Fármacos Neuroprotetores/farmacologia , Reconhecimento Psicológico/efeitos dos fármacos , Reconhecimento Psicológico/fisiologia
17.
Biol Pharm Bull ; 41(10): 1523-1529, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30270321

RESUMO

Hypotaurine is a precursor of taurine and a physiological antioxidant that circulates in adult and fetal plasma. The purpose of the present study was to clarify whether hypotaurine is a substrate of Slc6a/gamma-aminobutyric acid (GABA) transporter family members. Radiolabeled hypotaurine was synthesized from radiolabeled cysteamine and 2-aminoethanethiol dioxygenase. The uptakes of [3H]GABA, [3H]taurine, and [14C]hypotaurine by HEK293 cells expressing mouse GAT1/Slc6a1, TAUT/Slc6a6, GAT3/Slc6a11, BGT1/Slc6a12, and GAT2/Slc6a13 were measured. TAUT and GAT2 showed strong [14C]hypotaurine uptake activity, while BGT1 showed moderate activity, and GAT1 and GAT3 showed slight but significant activity. Mouse TAUT and GAT2 both showed Michaelis constants of 11 µM for hypotaurine uptake. GAT2-expressing cells pretreated with hypotaurine showed resistance to H2O2-induced oxidative stress. These results suggest that under physiological conditions, TAUT and GAT2 would be major contributors to hypotaurine transfer across the plasma membrane, and that uptake of hypotaurine via GAT2 contributes to the cellular resistance to oxidative stress.


Assuntos
Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Taurina/análogos & derivados , Ácido gama-Aminobutírico/metabolismo , Adaptação Fisiológica , Animais , Transporte Biológico , Células HEK293 , Humanos , Camundongos , Estresse Oxidativo , Taurina/metabolismo
18.
Cancer Biol Ther ; 19(4): 282-291, 2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29394133

RESUMO

In this study, we investigated the mechanism of miR-200c-3p and SLC6A1 in regulating cell activity of clear cell renal cell carcinoma (CCRCC). The mRNA and miRNA expressions of tissue specimens were analyzed by CapitalBio Corporation (Beijing, China). The expression of SLC6A1 in CCRCC cells was examined through qRT-PCR and western blot. The migration and invasion ability of 786-O cells was testified by transwell assay after transfected. 786-O cell proliferation ability was detected by MTT assay. Dual luciferase reporter assay verified the association between SLC6A1 and miR-200c-3p. SLC6A1 was high expressed and miR-200c-3p was low expressed in CCRCC tissues and cells. Besides, lower SLC6A1 expression indicated longer survival time and higher survival rate. MiR-200c-3p could directly target at SLC6A1 and reduce its expression. MiR-200c-3p inhibited the proliferation, migration and invasion in 786-O cells by down-regulating SLC6A1 expression. The results suggested that the miR-200c-3p served as a suppressor for CCRCC via down-regulating SLC6A1.


Assuntos
Carcinoma de Células Renais/genética , Proteínas da Membrana Plasmática de Transporte de GABA/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Renais/genética , MicroRNAs/metabolismo , Adulto , Idoso , Animais , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação para Baixo , Feminino , Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Células HEK293 , Humanos , Estimativa de Kaplan-Meier , Rim/patologia , Neoplasias Renais/mortalidade , Neoplasias Renais/patologia , Masculino , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Prognóstico , Organismos Livres de Patógenos Específicos , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Photochem Photobiol ; 94(1): 173-178, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28881432

RESUMO

5-aminolevulinic acid (5-ALA)-based photodynamic therapy (PDT) has been successfully used in the treatment of cancers. However, the mechanism of 5-ALA transportation into cancer cells is still not fully elucidated. Previous studies have confirmed that the efficiency of 5-ALA-PDT could be affected by the membrane skeleton protein 4.1R. In this study, we investigated the role of 4.1R in the transport of 5-ALA into cells. Wild-type (4.1R+/+ ) and 4.1R gene knockout (4.1R-/- ) mouse embryonic fibroblast (MEF) cells were incubated with 1 mm 5-ALA and different concentrations of specific inhibitors of GABA transporters GAT (1-3). Our results showed that the inhibition of GAT1 and GAT2 in particular markedly attenuated the intracellular PpIX production, reactive oxygen species (ROS) level and 5-ALA-induced photodamage. However, the inhibition of GAT3 did not show such effects. Further research showed that 4.1R-/- MEF cells had a lower expression of GAT1 and GAT2 than 4.1R+/+ MEF cells. Additionally, 4.1R directly bound to GAT1 and GAT2. Taken together, GAT1 and GAT2 transporters are involved in the uptake of 5-ALA in MEF cells. 4.1R plays an important role in transporting 5-ALA into cells via at least partly interaction with GAT1 and GAT2 transporters in 5-ALA-PDT.


Assuntos
Ácido Aminolevulínico/metabolismo , Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Proteínas dos Microfilamentos/metabolismo , Fármacos Fotossensibilizantes/metabolismo , Análise de Variância , Animais , Linhagem Celular , Fibroblastos/metabolismo , Proteínas da Membrana Plasmática de Transporte de GABA/genética , Inibidores da Captação de GABA/farmacologia , Camundongos , Camundongos Knockout , Proteínas dos Microfilamentos/genética , Protoporfirinas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Tiagabina/farmacologia
20.
Artigo em Inglês | MEDLINE | ID: mdl-28351548

RESUMO

Schizophrenia is associated with significant pathophysiological changes to interneurons within the prefrontal cortex (PFC), with mRNA and protein changes associated with the GABA network localized to specific interneuron subtypes. Methamphetamine is a commonly abused psychostimulant that can induce chronic psychosis and symptoms that are similar to schizophrenia, suggesting that chronic METH induced psychosis may be associated with similar brain pathology to schizophrenia in the PFC. The aim of this study, therefore, was to examine mRNA expression of interneuron markers across two regions of the PFC (prelimbic (PRL) and orbitofrontal cortices (OFC)) following METH sensitization, an animal model of METH psychosis. We also studied the association between GABA mRNA expression and interneuronal mRNA expression to identify whether particular changes to the GABA network could be localized to a specific inhibitory cellular phenotype. METH sensitization increased the transcriptional expression of calbindin, calretinin, somatostatin, cholecyctokinin and vasoactive intestinal peptide in the PRL while parvalbumin, calbindin, cholectokinin and vasoactive intestinal peptide were upregulated in the OFC. Based on our previous findings, we also found significant correlations between GAD67, GAT1 and parvalbumin while GAD67, GAD65 and GAT1 were positively correlated with cholecystokinin in the PRL of METH sensitized rats. Within the OFC, the expression of GABAAα1 was positively correlated with somatostatin while GABAAα5 was negatively associated with somatostatin and calbindin. These findings suggest that METH sensitization differentially changes the expression of mRNAs encoding for multiple peptides and calcium binding proteins across the PRL and the OFC. Furthermore, these findings support that changes to the GABA network may also occur within specific cell types. These results, therefore, provide the first evidence that METH sensitization mediates differential interneuronal pathology across the PRL and OFC and such changes could have profound consequences on behavior and cognitive output.


Assuntos
Sensibilização do Sistema Nervoso Central , Interneurônios/metabolismo , Interneurônios/patologia , Lobo Límbico/metabolismo , Metanfetamina/farmacologia , Córtex Pré-Frontal/metabolismo , RNA Mensageiro/metabolismo , Animais , Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Glutamato Descarboxilase/metabolismo , Lobo Límbico/patologia , Proteínas do Tecido Nervoso/metabolismo , Peptídeos/metabolismo , Córtex Pré-Frontal/patologia , Ratos , Receptores de GABA-A/biossíntese , Ácido gama-Aminobutírico/metabolismo
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