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1.
Environ Toxicol Pharmacol ; 80: 103451, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32599160

RESUMO

Juvenile Oncorhynchus mykiss (average weight: 22.3 g) were fed one of five selenomethionine diets (1.09, 8.79, 15.37, 30.79, or 61.58 mg Se/kg diet). After 4 weeks, hepatic catalase activity over 15.37 mg Se/kg diets was significantly decreased, and the glutathione peroxidase activity over 30.79 mg Se/kg diets was elevated compared to the controls. In the brain, the dopamine levels at 61.58 mg Se/kg diet and the serotonin levels over 15.37 mg Se/kg diets were significantly increased, whereas the 3,4-dihydroxyphenylacetic acid, homovanillic acid, and dopamine turnover, and the 5-hydroxyindoleacetic acid and serotonin turnover over 30.79 mg Se/kg diets were decreased. In muscle, the 3-nitrotyrosine level over 15.37 mg Se/kg diets, acetylcholine esterase activity over 30.79 mg Se/kg diets, and histological alterations over 8.79 mg Se/kg diets were increased. Our current results showed that selenomethionine disrupted dopamine and serotonin metabolism in the brain and damaged the neuromuscular system in skeletal muscle.


Assuntos
Encéfalo/efeitos dos fármacos , Fígado/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Oncorhynchus mykiss/metabolismo , Selenometionina/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Dopamina/metabolismo , Ecossistema , Fígado/metabolismo , Fígado/patologia , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Estresse Oxidativo/efeitos dos fármacos , Serotonina/metabolismo
2.
Cell Death Discov ; 5: 133, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31531231

RESUMO

Lipid rafts (LRs) play crucial roles in complex physiological processes, modulating innate and acquired immune responses to pathogens. The transmembrane C-type lectins human dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN) and its mouse homolog SIGN-R1 are distributed in LRs and expressed on splenic marginal zone (MZ) macrophages. The DC-SIGN-C1q or SIGN-R1-C1q complex could mediate the immunoglobulin (Ig)-independent classical complement pathway against Streptococcus pneumoniae. Precise roles of LRs during this complement pathway are unknown. Here we show that LRs are indispensable for accelerating the DC-SIGN- or SIGN-R1-mediated classical complement pathway against S. pneumoniae, thus facilitating rapid clearance of the pathogen. The trimolecular complex of SIGN-R1-C1q-C4 was exclusively enriched in LRs of splenic MZ macrophages and their localization was essential for activating C3 catabolism and enhancing pneumococcal clearance, which were abolished in SIGN-R1-knockout mice. However, DC-SIGN replacement on splenic MZ macrophage's LRs of SIGN-R1-depleted mice reversed these defects. Disruption of LRs dramatically reduced pneumococcal uptake and decomposition. Additionally, DC- SIGN, C1q, C4, and C3 were obviously distributed in splenic LRs of cadavers. Therefore, LRs on splenic SIGN-R1+ or DC-SIGN+ macrophages could provide spatially confined and optimal bidirectional platforms, not only for usual intracellular events, for example recognition and phagocytosis of pathogens, but also an unusual extracellular event such as the complement system. These findings improve our understanding of the orchestrated roles of the spleen, unraveling a new innate immune system initiated from splenic MZ LRs, and yielding answers to several long-standing problems, including the need to understand the profound role of LRs in innate immunity, the need to identify how such a small portion of splenic SIGN-R1+ macrophages (<0.05% of splenic macrophages) effectively resist S. pneumoniae, and the need to understand how LRs can promote the protective function of DC-SIGN against S. pneumoniae in the human spleen.

3.
PLoS One ; 14(1): e0210566, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30699135

RESUMO

Hypertensive disorders of pregnancy (HDP) is major complication of maternal-fetal outcomes in obstetric field. Although HDP is mainly defined by high blood pressure, the information about the relationship between prehypertension (preHTN, 120-139mmHg and 80-89mmHg) and HDP development is limited. The objective of this study is to determine the usefulness of preHTN before 20 weeks gestation and uterine artery (UtA) Doppler velocimetry as a predictor of HDP. A total of 2039 singleton pregnant women who had received continuous prenatal care were included in this study. The participants were classified into 2 groups based on the highest blood pressure (BP) under 20 gestational weeks as defined by the Joint National Committee 7: Normotensive (n = 1816) and preHTN pregnant women (n = 223). All preHTN pregnant women were assessed using UtA Doppler velocimetry, and the numbers of preHTN assessments were recorded. The risk of HDP was assessed in the PreHTN groups through patient history and Doppler velocimetry. Compared to normotensive patients, a total of 223 preHTN patients had a higher risk of preeclampsia (OR: 2.3; CI: 1.2-4.3), gestational hypertension (OR: 3.3; CI: 2.0-5.4) and any HDP (OR: 3.0; CI: 2.0-4.5). In the preHTN group, 134 (60.1%) patients had preHTN measured at least twice and 89 (39.9%) patients had preHTN. The results showed that two or more preHTN measurements have high sensitivity for predicting HDP (OR: 1.9; CI: 1.0-3.1; sensitivity: 83.8%; specificity: 47.2%). Additionally, the combination of abnormal UtA Doppler velocimetry results and at least two preHTN measurements showed a high accuracy in predicting HDP (OR: 2.9; CI: 1.1-4.1; sensitivity: 67.6%; specificity: 98.4%). In conclusion, close BP monitoring and recording of every preHTN event are important for pregnant women with preHTN history, and UtA Doppler examination in those women during the 2nd trimester can be a further aid in determining the risk of HDP.


Assuntos
Hipertensão Induzida pela Gravidez/diagnóstico por imagem , Hipertensão Induzida pela Gravidez/diagnóstico , Reologia , Ultrassonografia Doppler , Artéria Uterina/diagnóstico por imagem , Adulto , Feminino , Hospitais , Humanos , Valor Preditivo dos Testes , Gravidez , Curva ROC
4.
Nat Commun ; 9(1): 3284, 2018 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-30115930

RESUMO

Cytokines are involved in early host defense against pathogen infections. In particular, tumor necrosis factor (TNF) and interferon-gamma (IFN-γ) have critical functions in non-cytopathic elimination of hepatitis B virus (HBV) in hepatocytes. However, the molecular mechanisms and mediator molecules are largely unknown. Here we show that interleukin-32 (IL-32) is induced by TNF and IFN-γ in hepatocytes, and inhibits the replication of HBV by acting intracellularly to suppress HBV transcription and replication. The gamma isoform of IL-32 (IL-32γ) inhibits viral enhancer activities by downregulating liver-enriched transcription factors. Our data are validated in both an in vivo HBV mouse model and primary human hepatocytes. This study thus suggests that IL-32γ functions as intracellular effector in hepatocytes for suppressing HBV replication to implicate a possible mechanism of non-cytopathic viral clearance.


Assuntos
Antivirais/metabolismo , Citocinas/metabolismo , Vírus da Hepatite B/fisiologia , Interleucinas/metabolismo , Espaço Intracelular/metabolismo , Animais , Sequência de Bases , Linhagem Celular Tumoral , Modelos Animais de Doenças , Regulação para Baixo , Elementos Facilitadores Genéticos/genética , Hepatite B Crônica/metabolismo , Hepatite B Crônica/patologia , Fatores Nucleares de Hepatócito/metabolismo , Humanos , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Modelos Biológicos , Ligação Proteica , Transcrição Gênica , Replicação Viral
5.
Gut ; 67(1): 166-178, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28341749

RESUMO

OBJECTIVE: Interferons (IFNs) mediate direct antiviral activity. They play a crucial role in the early host immune response against viral infections. However, IFN therapy for HBV infection is less effective than for other viral infections. DESIGN: We explored the cellular targets of HBV in response to IFNs using proteome-wide screening. RESULTS: Using LC-MS/MS, we identified proteins downregulated and upregulated by IFN treatment in HBV X protein (HBx)-stable and control cells. We found several IFN-stimulated genes downregulated by HBx, including TRIM22, which is known as an antiretroviral protein. We demonstrated that HBx suppresses the transcription of TRIM22 through a single CpG methylation in its 5'-UTR, which further reduces the IFN regulatory factor-1 binding affinity, thereby suppressing the IFN-stimulated induction of TRIM22. CONCLUSIONS: We verified our findings using a mouse model, primary human hepatocytes and human liver tissues. Our data elucidate a mechanism by which HBV evades the host innate immune system.


Assuntos
Regiões 5' não Traduzidas/genética , Ilhas de CpG/genética , Vírus da Hepatite B/imunologia , Interferons/imunologia , Antígenos de Histocompatibilidade Menor/genética , Proteínas Repressoras/genética , Proteínas com Motivo Tripartido/genética , Animais , Regulação para Baixo/genética , Regulação para Baixo/imunologia , Epigênese Genética , Regulação da Expressão Gênica/imunologia , Hepatócitos/metabolismo , Humanos , Evasão da Resposta Imune , Fígado/metabolismo , Metilação , Camundongos , Antígenos de Histocompatibilidade Menor/biossíntese , Proteoma , Proteínas Repressoras/biossíntese , Proteínas com Motivo Tripartido/biossíntese
6.
J Reprod Immunol ; 124: 30-37, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29049918

RESUMO

Immune tolerance at feto-maternal interfaces is a complex phenomenon. Although maternal decidual macrophages are well-known immune cells, little is known about fetal-derived macrophages (Hofbauer cells) within chorionic villi. Preeclampsia (PE) is a major cause of maternal mortality in the field of obstetrics, and the innate immunological role of maternal decidual macrophages is well known. In this study, we assessed the differential phenotypes and marker expression in fetal macrophages, known as dendritic cell-specific ICAM-grabbing non-integrin (DC-SIGN)-positive Hofbauer cells. We compared Hofbauer cell properties between normal and PE placenta chorionic villi and performed sequential staining of DC-SIGN, CD14, and CD68 to evaluate the existence of Hofbauer cells. Furthermore, to evaluate the immunological function of these cells, we stained the cells for CD163, a marker of immunoregulatory type 2 (M2) macrophages. Additionally, we examined the expression of the immunosuppressive cytokine interleukin (IL)-10, which is known to be produced by M2 macrophages. DC-SIGN+/CD14+, DC-SIGN+/CD68+, and CD163+/DC-SIGN+ cells were quantified based on photomicrographs. The results showed that CD14, CD163, DC-SIGN, and IL-10 levels were significantly downregulated in PE compared with normal. Additionally, CD163+/DC-SIGN+ Hofbauer cells were significantly less frequent in PE than in normal. DC-SIGN Hofbauer cells produced IL-10 at lower levels in the PE than in the normal. Thus, we speculate that fetal-derived Hofbauer cells may play an important role in normal pregnancy with immunosuppressive effects based on their M2 macrophage characteristics to maintain immune tolerance during pregnancy. Additionally, in PE, these functions were defective, supporting the roles of these macrophages in PE development.


Assuntos
Moléculas de Adesão Celular/metabolismo , Vilosidades Coriônicas/patologia , Histiócitos/metabolismo , Lectinas Tipo C/metabolismo , Pré-Eclâmpsia/imunologia , Receptores de Superfície Celular/metabolismo , Adulto , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Células Cultivadas , Feminino , Regulação da Expressão Gênica , Histiócitos/imunologia , Humanos , Tolerância Imunológica , Interleucina-10/metabolismo , Receptores de Lipopolissacarídeos/metabolismo , Macrófagos/imunologia , Gravidez
7.
Pflugers Arch ; 469(5-6): 829-842, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28303387

RESUMO

Activation of L-type voltage-dependent Ca2+ channels (VDCCL) by membrane stretch contributes to many biological responses such as myogenic contraction of arteries. However, mechanism for the stretch-induced VDCCL activation is unclear. In this study, we examined the hypothesis that caveolar remodeling and its related signaling cascade contribute to the stretch-induced activation of VDCCL in rat mesenteric arterial smooth muscle cells. The VDCCL currents were recorded with nystatin-perforated or with conventional whole-cell patch-clamp technique. Hypotonic (~230 mOsm) swelling-induced membrane stretch reversibly increased the VDCCL currents. Electron microscope and confocal imaging analysis revealed that both hypotonic swelling and cholesterol depletion by methyl-ß-cychlodextrin (MßCD) similarly disrupted the caveolae structure and translocated caveolin-1 (Cav-1) from membrane to cytosolic space. Accordingly, MßCD also increased VDCCL currents. Moreover, subsequent hypotonic swelling after MßCD treatment failed to increase the VDCCL currents further. Western blotting experiments revealed that hypotonic swelling phosphorylated Cav-1 and JNK. Inhibitors of tyrosine kinases (genistein) and JNK (SP00125) prevented the swelling-induced facilitation of VDCCL currents. Knockdown of Cav-1 by small interfering RNA blocked both the VDCCL current facilitation by stretch and the related phosphorylation of JNK. Taken together, the results suggest that membrane stretch is transduced to the facilitation of VDCCL currents via caveolar structure-dependent tyrosine phosphorylation of Cav-1 and subsequent activation of JNK in rat mesenteric arterial myocytes.


Assuntos
Canais de Cálcio/metabolismo , Cavéolas/metabolismo , Mecanotransdução Celular , Miócitos de Músculo Liso/metabolismo , Potenciais de Ação , Animais , Cavéolas/ultraestrutura , Caveolina 1/metabolismo , Células Cultivadas , Colesterol/deficiência , MAP Quinase Quinase 4/metabolismo , Masculino , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/fisiologia , Miócitos de Músculo Liso/ultraestrutura , Pressão Osmótica , Ratos , Ratos Sprague-Dawley , beta-Ciclodextrinas/farmacologia
8.
Neurochem Int ; 99: 52-61, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27296112

RESUMO

Although previous studies have suggested that neuronal nitric oxide synthase (nNOS)-derived NO has neuroprotective effects on the development of Alzheimer's disease (AD), the underlying molecular mechanisms are not fully elucidated. Here, we investigated whether and how disruption of nNOS dimerization contributes to the development of AD. No differences in synaptic number or expression of synaptic markers, including synaptophysin and postsynaptic density 95, were found in the cortex of 5 × FAD mice, which possess 5 familial AD mutations, at 6 months of age compared with control littermates. nNOS dimerization was disrupted in the 5 × FAD cortex, accompanied by an increase in reactive oxygen species (ROS) production. The subcellular distribution of cyclin-dependent kinase 5 (CDK5) shifted more diffusely toward a cytosolic compartment, but there was no change in total expression. Furthermore, the levels of p25, a CDK5 activator, increased significantly and it colocalized with nNOS in the 5 × FAD cortex. In silico analysis revealed that a new nNOS-specific GSP (glycine-serine-proline) motif was well-conserved across species at nNOS-Ser(293), which is located ahead of the N-terminal hook. This motif was not present in the closely related isoform, endothelial NOS. Motif scan analysis also predicted that CDK5 can phosphorylate nNOS-Ser(293) with a high likelihood. An in vitro phosphorylation assay clearly showed that CDK5/p25 does indeed phosphorylate nNOS-Ser(293). Finally, nNOS-S293D mutant, a phosphomimetic form of nNOS-Ser(293), and nNOS-S293A mutant, a neutral form of nNOS-Ser(293), significantly decreased nNOS dimerization and NO production. Taken together, our results demonstrate that nNOS dimers are disrupted in the 5 × FAD cortex, and nNOS-Ser(293), a potential site of CDK5 phosphorylation, may be involved in the decrease in nNOS dimerization and NO production, and the development of AD.


Assuntos
Doença de Alzheimer/metabolismo , Quinase 5 Dependente de Ciclina/metabolismo , Neurônios/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Multimerização Proteica/fisiologia , Serina/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Animais , Bovinos , Células Cultivadas , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Quinase 5 Dependente de Ciclina/genética , Feminino , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Neurônios/patologia , Óxido Nítrico Sintase Tipo I/genética , Ratos , Espécies Reativas de Oxigênio/metabolismo , Serina/genética
9.
J Hepatol ; 64(2): 268-277, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26409214

RESUMO

BACKGROUND & AIMS: Cytokines are key molecules implicated in the defense against virus infection. Tumor necrosis factor-alpha (TNF-α) is well known to block the replication of hepatitis B virus (HBV). However, the molecular mechanism and the downstream effector molecules remain largely unknown. METHODS: In this study, we investigated the antiviral effect and mechanism of p22-FLIP (FLICE-inhibitory protein) by ectopic expression in vitro and in vivo. In addition, to provide the biological relevance of our study, we examined that the p22-FLIP is involved in TNF-α-mediated suppression of HBV in primary human hepatocytes. RESULTS: We found that p22-FLIP, a newly discovered c-FLIP cleavage product, inhibited HBV replication at the transcriptional level in both hepatoma cells and primary human hepatocytes, and that c-FLIP conversion to p22-FLIP was stimulated by the TNF-α/NF-κB pathway. p22-FLIP inhibited HBV replication through the upregulation of HNF3ß but downregulation of HNF4α, thus inhibiting both HBV enhancer elements. Finally, p22-FLIP potently inhibited HBV DNA replication in a mouse model of HBV replication. CONCLUSIONS: Taken together, these findings suggest that the anti-apoptotic p22-FLIP serves a novel function of inhibiting HBV transcription, and mediates the antiviral effect of TNF-α against HBV replication.


Assuntos
Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/metabolismo , Vírus da Hepatite B , Fator de Necrose Tumoral alfa , Replicação Viral/efeitos dos fármacos , Animais , Antivirais/farmacologia , Linhagem Celular , DNA Viral/metabolismo , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/fisiologia , Fatores Nucleares de Hepatócito/metabolismo , Hepatócitos/metabolismo , Humanos , Camundongos , Modelos Animais , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
10.
J Neurosci Res ; 92(5): 658-70, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24510599

RESUMO

Preconception exposure to EtOH through the paternal route may affect neurobehavioral and developmental features of offspring. This study investigates the effects of paternal exposure to EtOH before conception on the hyperactivity, inattention, and impulsivity behavior of male offspring in mice. Sire mice were treated with EtOH in a concentration range approximating human binge drinking (0-4 g/kg/day EtOH) for 7 weeks and mated with untreated females mice to produce offspring. EtOH exposure to sire mice induced attention deficit hyperactivity disorder (ADHD)-like hyperactive, inattentive, and impulsive behaviors in offspring. As a mechanistic link, both protein and mRNA expression of dopamine transporter (DAT), a key determinant of ADHD-like phenotypes in experimental animals and humans, were significantly decreased by paternal EtOH exposure in cerebral cortex and striatum of offspring mice along with increased methylation of a CpG region of the DAT gene promoter. The increase in methylation of DAT gene promoter was also observed in the sperm of sire mice, suggesting germline changes in the epigenetic methylation signature of DAT gene by EtOH exposure. In addition, the expression of two key regulators of methylation-dependent epigenetic regulation of functional gene expression, namely, MeCP2 and DNMT1, was markedly decreased in offspring cortex and striatum sired by EtOH-exposed mice. These results suggest that preconceptional exposure to EtOH through the paternal route induces behavioral changes in offspring, possibly via epigenetic changes in gene expression, which is essential for the regulation of ADHD-like behaviors.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/induzido quimicamente , Depressores do Sistema Nervoso Central/toxicidade , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Epigênese Genética/efeitos dos fármacos , Etanol/toxicidade , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Animais , Aprendizagem da Esquiva/fisiologia , Modelos Animais de Doenças , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Comportamento de Ingestão de Líquido , Comportamento Exploratório/fisiologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto/fisiologia , Proteína 2 de Ligação a Metil-CpG/genética , Proteína 2 de Ligação a Metil-CpG/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Fenótipo , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente
11.
Arch Dermatol Res ; 306(4): 347-57, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24402284

RESUMO

Abnormal scarring results from the expression and composition of extracellular matrix molecules. The transcription and translation of collagens I and III, fibronectin, laminin, periostin, and tenascin are all increased in raised dermal scar tissue. However, human keloid development is not fully defined. In this study, we identified proteins expressed differentially between normal skin and keloid scar tissues and examined their function in keloid formation using fibroblasts. Skin specimens from normal volunteers and patients with keloids were obtained by skin biopsy. Whole proteins were isolated by two-dimensional electrophoresis, and differentially expressed proteins were identified by matrix-assisted laser desorption/ionization-time of flight/time of flight mass spectrometry. Protein function was determined by proliferation assay using annexin A2-overexpressing keloid fibroblasts. The expression of 11 protein spots was altered by at least 1.5-fold in patients with keloids than in normal volunteers. Of these proteins, annexin A2, a pre-serum amyloid P component, serum albumin precursor, and tryptase-I, were down-regulated in keloid tissue compared to normal skin. Collagen alpha 1(V) chain precursor, collagen alpha 1(I) chain precursor, ferritin light subunit, alpha 1(III) collagen, 6-phosphogluconolactonase, and calponin 2 were up-regulated. Diminished expression of annexin A2 was confirmed by immunoblotting and immunohistochemistry. Treatment with the recombinant human epidermal growth factor increased proliferation of keloid fibroblasts, which was more inhibited in annexin A2-overexpressing fibroblasts than in non-transfected control cells. These results imply that annexin A2 may participate in keloid formation by inhibiting keloid fibroblast proliferation. Therefore, it is concluded that annexin A2 may be a valuable therapeutic target for keloid lesions.


Assuntos
Anexina A2/biossíntese , Proliferação de Células , Fibroblastos , Queloide/metabolismo , Pele/metabolismo , Adolescente , Adulto , Idoso , Apoferritinas/biossíntese , Hidrolases de Éster Carboxílico/biossíntese , Células Cultivadas , Colágeno Tipo I/biossíntese , Colágeno Tipo III/biossíntese , Colágeno Tipo V/biossíntese , Regulação para Baixo , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Proteínas dos Microfilamentos/biossíntese , Pessoa de Meia-Idade , Interferência de RNA , RNA Interferente Pequeno , Albumina Sérica/biossíntese , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Triptases/biossíntese , Regulação para Cima , Adulto Jovem
12.
J Ginseng Res ; 37(4): 401-12, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24235858

RESUMO

Korean Red Ginseng (KRG) is an oriental herbal preparation obtained from Panax ginseng Meyer (Araliaceae). To expand our understanding of the action of KRG on central nervous system (CNS) function, we examined the effects of KRG on tissue plasminogen activator (tPA)/plasminogen activator inhibitor-1 (PAI-1) expression in rat primary astrocytes. KRG extract was treated in cultured rat primary astrocytes and neuron in a concentration range of 0.1 to 1.0 mg/mL and the expression of functional tPA/PAI-1 was examined by casein zymography, Western blot and reverse transcription-polymerase chain reaction. KRG extracts increased PAI-1 expression in rat primary astrocytes in a concentration dependent manner (0.1 to 1.0 mg/mL) without affecting the expression of tPA itself. Treatment of 1.0 mg/mL KRG increased PAI-1 protein expression in rat primary astrocytes to 319.3±65.9% as compared with control. The increased PAI-1 expression mediated the overall decrease in tPA activity in rat primary astrocytes. Due to the lack of PAI-1 expression in neuron, KRG did not affect tPA activity in neuron. KRG treatment induced a concentration dependent activation of PI3K, p38, ERK1/2, and JNK in rat primary astrocytes and treatment of PI3K or MAPK inhibitors such as LY294002, U0126, SB203580, and SP600125 (10 µM each), significantly inhibited 1.0 mg/mL KRG-induced expression of PAI- 1 and down-regulation of tPA activity in rat primary astrocytes. Furthermore, compound K but not other ginsenosides such as Rb1 and Rg1 induced PAI-1 expression. KRG-induced up-regulation of PAI-1 in astrocytes may play important role in the regulation of overall tPA activity in brain, which might underlie some of the beneficial effects of KRG on CNS such as neuroprotection in ischemia and brain damaging condition as well as prevention or recovery from addiction.

13.
Biomol Ther (Seoul) ; 21(3): 222-8, 2013 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-24265868

RESUMO

Although the role of α-synuclein aggregation on Parkinson's disease is relatively well known, the physiological role and the regulatory mechanism governing the expression of α-synuclein are unclear yet. We recently reported that α-synuclein is expressed and secreted from cultured astrocytes. In this study, we investigated the effect of valproic acid (VPA), which has been suggested to provide neuroprotection by increasing α-synuclein in neuron, on α-synuclein expression in rat primary astrocytes. VPA concentrationdependently increased the protein expression level of α-synuclein in cultured rat primary astrocytes with concomitant increase in mRNA expression level. Likewise, the level of secreted α-synuclein was also increased by VPA. VPA increased the phosphorylation of Erk1/2 and JNK and pretreatment of a JNK inhibitor SP600125 prevented the VPA-induced increase in α-synuclein. Whether the increased α-synuclein in astrocytes is involved in the reported neuroprotective effects of VPA awaits further investigation.

14.
Hepatology ; 58(2): 762-76, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23483589

RESUMO

UNLABELLED: Liver regeneration after liver damage caused by toxins and pathogens is critical for liver homeostasis. Retardation of liver proliferation was reported in hepatitis B virus (HBV) X protein (HBx)-transgenic mice. However, the underlying mechanism of the HBx-mediated disturbance of liver regeneration is unknown. We investigated the molecular mechanism of the inhibition of liver regeneration using liver cell lines and a mouse model. The mouse model of acute HBV infection was established by hydrodynamic injection of viral DNA. Liver regeneration after partial hepatectomy was significantly inhibited in the HBV DNA-treated mice. Mechanism studies have revealed that the expression of urokinase-type plasminogen activator (uPA), which regulates the activation of hepatocyte growth factor (HGF), was significantly decreased in the liver tissues of HBV or HBx-expressing mice. The down-regulation of uPA was further confirmed using liver cell lines transiently or stably transfected with HBx and the HBV genome. HBx suppressed uPA expression through the epigenetic regulation of the uPA promoter in mouse liver tissues and human liver cell lines. Expression of HBx strongly induced hypermethylation of the uPA promoter by recruiting DNA methyltransferase (DNMT) 3A2. CONCLUSION: Taken together, these results suggest that infection of HBV impairs liver regeneration through the epigenetic dysregulation of liver regeneration signals by HBx.


Assuntos
Epigênese Genética/fisiologia , Vírus da Hepatite B/genética , Vírus da Hepatite B/fisiologia , Hepatite B/fisiopatologia , Regeneração Hepática/fisiologia , Ativador de Plasminogênio Tipo Uroquinase/fisiologia , Animais , Linhagem Celular , Proliferação de Células , DNA (Citosina-5-)-Metiltransferases/fisiologia , DNA Metiltransferase 3A , DNA Viral/genética , Modelos Animais de Doenças , Hepatectomia , Hepatite B/patologia , Fator de Crescimento de Hepatócito/fisiologia , Hepatócitos/patologia , Técnicas In Vitro , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Transdução de Sinais/fisiologia , Transativadores/fisiologia , Proteínas Virais Reguladoras e Acessórias
15.
Yonsei Med J ; 54(2): 494-9, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23364987

RESUMO

PURPOSE: Recently, COMMD1 has been identified as a novel interactor and regulator of hypoxia-inducible factor-1 and nuclear factor kappa B transcriptional activity. The goal of this study was to determine the difference of COMMD1 expression in the placentas of women with normal and preeclamptic (PE) pregnancies. MATERIALS AND METHODS: Immnoperoxidase and immunofluorescent staining for COMMD1 was performed on nine normal and nine severe PE placental tissues, and COMMD1 mRNA expression was quantified by quantitative reverse transcription polymerase chain reaction. RESULTS: The expression of mRNA of COMMD1 was significantly higher in the study group than in the control group. The immunoreactivity was higher especially in the syncytiotrophoblast of PE placentas than in the control group. CONCLUSION: This study demonstrated increased placental COMMD1 expression in women with severe preeclampsia compared to that found in women with normal pregnancies, and this finding might contribute to a better understanding of the pathophysiology of preeclampsia.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/isolamento & purificação , Adulto , Feminino , Humanos , Gravidez , RNA Mensageiro/metabolismo
16.
Eur J Obstet Gynecol Reprod Biol ; 168(1): 40-4, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23347603

RESUMO

OBJECTIVE: Lately, DJ-1 has been identified as a novel mediator of hypoxia-induced cellular responses. The aim of this study was to determine the difference of DJ-1 expression in the placentas of women with normal and preeclamptic pregnancies. STUDY DESIGN: DJ-1 mRNA expression was quantified by quantitative reverse transcription polymerase chain reaction (RT-PCR). Also, immunoperoxidase and immunofluorescent staining for DJ-1 was performed on 11 normal and 12 preeclamptic placental tissues. RESULTS: The expression of mRNA of DJ-1 was significantly higher in the study group than in the control group. The immunoreactivity was especially higher in the syncytiotrophoblast of preeclamptic placentas compared to the control group. CONCLUSION: Overexpression of the DJ-1 protein in the placentas of severe PE patients is thought to be a causative or compensatory mechanism in response to hypoxia, and this finding might contribute to a better understanding of the pathophysiology of preeclampsia.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/biossíntese , Proteínas Oncogênicas/biossíntese , Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , Adulto , Feminino , Humanos , Gravidez , Proteína Desglicase DJ-1 , RNA Mensageiro/metabolismo , Trofoblastos/metabolismo
17.
PLoS One ; 8(1): e53911, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23349763

RESUMO

Presently, few treatments for spinal cord injury (SCI) are available and none have facilitated neural regeneration and/or significant functional improvement. Agmatine (Agm), a guanidinium compound formed from decarboxylation of L-arginine by arginine decarboxylase, is a neurotransmitter/neuromodulator and been reported to exert neuroprotective effects in central nervous system injury models including SCI. The purpose of this study was to demonstrate the multifaceted effects of Agm on functional recovery and remyelinating events following SCI. Compression SCI in mice was produced by placing a 15 g/mm(2) weight for 1 min at thoracic vertebra (Th) 9 segment. Mice that received an intraperitoneal (i.p.) injection of Agm (100 mg/kg/day) within 1 hour after SCI until 35 days showed improvement in locomotor recovery and bladder function. Emphasis was made on the analysis of remyelination events, neuronal cell preservation and ablation of glial scar area following SCI. Agm treatment significantly inhibited the demyelination events, neuronal loss and glial scar around the lesion site. In light of recent findings that expressions of bone morphogenetic proteins (BMPs) are modulated in the neuronal and glial cell population after SCI, we hypothesized whether Agm could modulate BMP- 2/4/7 expressions in neurons, astrocytes, oligodendrocytes and play key role in promoting the neuronal and glial cell survival in the injured spinal cord. The results from computer assisted stereological toolbox analysis (CAST) demonstrate that Agm treatment dramatically increased BMP- 2/7 expressions in neurons and oligodendrocytes. On the other hand, BMP- 4 expressions were significantly decreased in astrocytes and oligodendrocytes around the lesion site. Together, our results reveal that Agm treatment improved neurological and histological outcomes, induced oligodendrogenesis, protected neurons, and decreased glial scar formation through modulating the BMP- 2/4/7 expressions following SCI.


Assuntos
Agmatina/farmacologia , Proteínas Morfogenéticas Ósseas/metabolismo , Neuroglia/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Recuperação de Função Fisiológica/efeitos dos fármacos , Traumatismos da Medula Espinal/tratamento farmacológico , Agmatina/administração & dosagem , Animais , Western Blotting , Proteína Morfogenética Óssea 2/metabolismo , Proteína Morfogenética Óssea 4/metabolismo , Proteína Morfogenética Óssea 7/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Imuno-Histoquímica , Injeções Intraperitoneais , Masculino , Camundongos , Camundongos Endogâmicos ICR , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Bainha de Mielina/efeitos dos fármacos , Bainha de Mielina/fisiologia , Bainha de Mielina/ultraestrutura , Neuroglia/metabolismo , Neurônios/metabolismo , Recuperação de Função Fisiológica/fisiologia , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Medula Espinal/ultraestrutura , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/fisiopatologia
18.
Neurochem Res ; 38(3): 620-31, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23283698

RESUMO

Prenatal exposure to alcohol has consistently been associated with adverse effects on neurodevelopment, which is collectively called fetal alcohol spectrum disorder (FASD). Increasing evidence suggest that prenatal exposure to alcohol increases the risk of developing attention deficit/hyperactivity disorder-like behavior in human. In this study, we investigated the behavioral effects of prenatal exposure to EtOH in offspring mice and rats focusing on hyperactivity and impulsivity. We also examined changes in dopamine transporter and MeCP2 expression, which may underlie as a key neurobiological and epigenetic determinant in FASD and hyperactive, inattentive and impulsive behaviors. Mouse or rat offspring born from dam exposed to alcohol during pregnancy (EtOH group) showed hyper locomotive activity, attention deficit and impulsivity. EtOH group also showed increased dopamine transporter and norepinephrine transporter level compared to control group in the prefrontal cortex and striatum. Prenatal exposure to EtOH also significantly decreased the expression of MeCP2 in both prefrontal cortex and striatum. These results suggest that prenatal exposure to EtOH induces hyperactive, inattentive and impulsive behaviors in rodent offspring that might be related to global epigenetic changes as well as aberration in catecholamine neurotransmitter transporter system.


Assuntos
Etanol/toxicidade , Animais , Transtorno do Deficit de Atenção com Hiperatividade/induzido quimicamente , DNA (Citosina-5-)-Metiltransferase 1 , DNA (Citosina-5-)-Metiltransferases/metabolismo , Proteínas da Membrana Plasmática de Transporte de Dopamina/biossíntese , Epigênese Genética/efeitos dos fármacos , Feminino , Transtornos do Espectro Alcoólico Fetal/psicologia , Comportamento Impulsivo/induzido quimicamente , Proteína 2 de Ligação a Metil-CpG/metabolismo , Camundongos , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/biossíntese , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Ratos
19.
Toxicol Res ; 29(3): 173-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24386517

RESUMO

In-utero exposure to valproic acid (VPA) has been known as a potent inducer of autism spectrum disorder (ASD), not only in humans, but also in animals. In addition to the defects in communication and social interaction as well as repetitive behaviors, ASD patients usually suffer from gastrointestinal (GI) problems. However, the exact mechanism underlying these disorders is not known. In this study, we examined the gross GI tract structure and GI motility in a VPA animal model of ASD. On embryonic day 12 (E12), 4 pregnant Sprague-Dawley (SD) rats were subcutaneously injected with VPA (400 mg/kg) in the treatment group, and with phosphate buffered saline (PBS) in the control group; the resulting male offspring were analyzed at 4 weeks of age. VPA exposure decreased the thickness of tunica mucosa and tunica muscularis in the stomach and ileum. Other regions such as duodenum, jejunum, and colon did not show a significant difference. In high-resolution microscopic observation, atrophy of the parietal and chief cells in the stomach and absorptive cells in the ileum was observed. In addition, decreased staining of the epithelial cells was observed in the hematoxylin and eosin (H&E)-stained ileum section. Furthermore, decreased motility in GI tract was also observed in rat offspring prenatally exposed to VPA. However, the mechanism underlying GI tract defects in VPA animal model as well as the association between abnormal GI structure and function with ASD is yet to be clearly understood. Nevertheless, the results from the present study suggest that this VPA ASD model undergoes abnormal changes in the GI structure and function, which in turn could provide beneficial clues pertaining to the pathophysiological relevance of GI complications and ASD phenotypes.

20.
J Neurochem ; 123(2): 226-38, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22817682

RESUMO

J. Neurochem. (2012) 123, 226-238. ABSTRACT: Fragile X syndrome (FXS), the most common single genetic cause of mental retardation and autistic spectrum disease, occurs when FMR1 gene is mutated. FMR1 encodes fragile X mental retardation protein (FMRP) which regulates translation of mRNAs playing important roles in the development of neurons as well as formation and maintenance of synapses. To examine whether FMRP regulates cell viability, we induced apoptosis in rat primary cortical neurons with glutamate in vitro and with middle cerebral artery occlusion (MCAO) in striatal neurons in vivo. Both conditions elicited a rapid, but transient FMRP expression in neurons. This up-regulated FMRP expression was abolished by pre-treatment with PI3K and Protein Kinase B (Akt) inhibitors: LY294002, Akt inhibitor IV, and VIII. Reduced FMRP expression in vitro or in vivo using small hairpin Fmr1 virus exacerbated cell death by glutamate or MCAO, presumably via hypophosphorylation of Akt and reduced expression of B-cell lymphoma-extra large (Bcl-xL). However, over-expression of FMRP using enhanced green fluorescent protein (eGFP)-FMRP constructs alleviated cell death, increased Akt activity, and enhanced Bcl-xL production. The pro-survival role of Akt-dependent up-regulation of FMRP in glutamate-stimulated cultured neuron as well as in ischemic brain may have a clinical importance in FXS as well as in neurodegenerative disorders and traumatic brain injury.


Assuntos
Retroalimentação Fisiológica/fisiologia , Proteína do X Frágil da Deficiência Intelectual/fisiologia , Neurônios/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Transdução de Sinais/fisiologia , Animais , Apoptose/fisiologia , Morte Celular/fisiologia , Sobrevivência Celular/fisiologia , Células Cultivadas , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/patologia , Infarto da Artéria Cerebral Média/prevenção & controle , Masculino , Neurônios/patologia , Ratos , Ratos Wistar
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