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1.
J Physiol Sci ; 71(1): 18, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34134629

RESUMO

We examined whether the chemogenetic activation of endogenous arginine vasopressin (AVP) affects central nesfatin-1/NucB2 neurons, using a transgenic rat line that was previously generated. Saline (1 mL/kg) or clozapine-N-oxide (CNO, 1 mg/mL/kg), an agonist for hM3Dq, was subcutaneously administered in adult male AVP-hM3Dq-mCherry transgenic rats (300-370 g). Food and water intake were significantly suppressed after subcutaneous (s.c.) injection of CNO, with aberrant circadian rhythmicity. The percentages of Fos expression in nesfatin-1/NucB2-immunoreactive neurons were significantly increased in the hypothalamus and brainstem at 120 min after s.c. injection of CNO. Suppressed food intake that was induced by chemogenetic activation of endogenous AVP was ablated after intracerebroventricularly administered nesfatin-1/NucB2-neutralizing antibody in comparison with vehicle, without any alteration of water intake nor circadian rhythmicity. These results suggest that chemogenetic activation of endogenous AVP affects, at least in part, central nesfatin-1/NucB2 neurons and may exert anorexigenic effects in the transgenic rats.


Assuntos
Depressores do Apetite/farmacologia , Arginina Vasopressina/fisiologia , Clozapina/análogos & derivados , Ingestão de Líquidos/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Nucleobindinas/metabolismo , Transdução de Sinais , Animais , Apetite/efeitos dos fármacos , Apetite/fisiologia , Clozapina/farmacologia , Ingestão de Líquidos/fisiologia , Ingestão de Alimentos/fisiologia , Masculino , Nucleobindinas/fisiologia , Ratos Transgênicos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
2.
Sci Rep ; 10(1): 13671, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32792584

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is characterized by excessive accumulation of hepatic triglycerides (TG) and hyperglycemia arising due to persistent insulin resistance, and is profoundly linked to obesity. However, there is currently no established treatment for NAFLD in obese human subjects. We previously isolated Helz2, the expression of which was upregulated in human and mouse NAFLD, and its deletion activated the hepatic expression of functional leptin receptor long form (Leprb) and suppressed NAFLD development and body weight (BW) gain in obese mice. A high-throughput assay of small-molecule drugs revealed that guanabenz acetate (Ga), originally used to treat hypertension, possesses a high affinity constant against HELZ2, and its administration activates LEPRB expression in HepG2 cells in vitro. The chronic oral administration of Ga shows the selective leptin sensitization in the liver via upregulation of hepatic Leprb expression, which affects expression of genes involved in lipogenesis and fatty acid ß-oxidation and diminishes hepatocyte hypertrophy with droplets enriched in TG in high-fat diet-induced obese mice. This activity significantly improves insulin resistance to decrease hyperglycemia and hepatocyte and adipocyte weights, resulting in BW reduction without reducing food intake. Regarding drug repositioning, Ga has the potential to effectively treat NAFLD and hyperglycemia in obese patients.


Assuntos
Guanabenzo/administração & dosagem , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Proteínas Nucleares/metabolismo , Obesidade/tratamento farmacológico , Receptores para Leptina/metabolismo , Administração Oral , Animais , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Reposicionamento de Medicamentos , Regulação da Expressão Gênica , Guanabenzo/farmacologia , Células Hep G2 , Humanos , Lipogênese/efeitos dos fármacos , Camundongos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Proteínas Nucleares/antagonistas & inibidores , Obesidade/induzido quimicamente , Obesidade/metabolismo
3.
Sci Rep ; 7: 45819, 2017 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-28374855

RESUMO

Fibroblast growth factor 21 (FGF21), liver-derived hormone, exerts diverse metabolic effects, being considered for clinical application to treat obesity and diabetes. However, its anorexigenic effect is debatable and whether it involves the central mechanism remains unclarified. Moreover, the neuron mediating FGF21's anorexigenic effect and the systemic energy state supporting it are unclear. We explored the target neuron and fed/fasted state dependence of FGF21's anorexigenic action. Intracerebroventricular (ICV) injection of FGF21 markedly suppressed food intake in fed mice with elevated blood glucose. FGF21 induced c-Fos expression preferentially in hypothalamic paraventricular nucleus (PVN), and increased mRNA expression selectively for nucleobindin 2/nesfatin-1 (NUCB2/Nesf-1). FGF21 at elevated glucose increased [Ca2+]i in PVN NUCB2/Nesf-1 neurons. FGF21 failed to suppress food intake in PVN-preferential Sim1-Nucb2-KO mice. These findings reveal that FGF21, assisted by elevated glucose, activates PVN NUCB2/Nesf-1 neurons to suppress feeding under fed states, serving as the glycemia-monitoring messenger of liver-hypothalamic network for integrative regulation of energy and glucose metabolism.


Assuntos
Glicemia , Fatores de Crescimento de Fibroblastos/farmacologia , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , Saciação/fisiologia , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Ligação a DNA/metabolismo , Ingestão de Alimentos , Infusões Intraventriculares , Masculino , Camundongos , Camundongos Knockout , Proteínas do Tecido Nervoso/metabolismo , Neurônios/efeitos dos fármacos , Nucleobindinas , Núcleo Hipotalâmico Paraventricular/metabolismo , Proteínas Proto-Oncogênicas c-fos
4.
Endocrinology ; 157(6): 2322-32, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27105386

RESUMO

Nesfatin-1, derived from nucleobindin-2 (NUCB2), is expressed in the hypothalamus, including the paraventricular nucleus (PVN), an integrative center for energy homeostasis. However, precise role of the NUCB2/nesfatin-1 in PVN remains less defined. The present study aimed to clarify physiological and/or pathophysiological roles of endogenous NUCB2/nesfatin-1 in PVN by using adeno-associated virus vectors encoding short hairpin RNAs targeting NUCB2 in mice. PVN-specific NUCB2 knockdown primarily increased food intake and decreased plasma oxytocin level specifically in light phase, leading to increased body weight gain without affecting energy expenditure. Furthermore, high-salt diet increased the systolic blood pressure, plasma arginine vasopressin (AVP) and AVP mRNA expression in PVN, and all these changes were blunted by PVN-specific NUCB2 knockdown. These results reveal that the endogenous NUCB2/nesfatin-1 in PVN regulates PVN AVP and oxytocin and consequently the fluid and energy balance.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Ocitocina/metabolismo , Núcleo Hipotalâmico Paraventricular/metabolismo , Vasopressinas/metabolismo , Adiposidade/genética , Adiposidade/fisiologia , Animais , Western Blotting , Proteínas de Ligação ao Cálcio/genética , Calorimetria , Proteínas de Ligação a DNA/genética , Comportamento Alimentar/fisiologia , Imuno-Histoquímica , Resistência à Insulina/genética , Resistência à Insulina/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas do Tecido Nervoso/genética , Nucleobindinas , RNA Interferente Pequeno/genética
5.
Biochem Biophys Res Commun ; 456(4): 913-8, 2015 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-25534851

RESUMO

An adipokine leptin plays a central role in the regulation of feeding and energy homeostasis via acting on the hypothalamus. However, its downstream neuronal mechanism is not thoroughly understood. The neurons expressing nucleobindin-2 (NUCB2)-derived nesfatin-1 in the hypothalamic paraventricular nucleus (PVN) have been implicated in feeding and energy homeostasis. The present study aimed to explore the role of PVN NUCB2/nesfatin-1 in the leptin action, by using adeno-associated virus (AAV) vectors encoding shRNA targeting NUCB2 (AAV-NUCB2-shRNA). Leptin directly interacted and increased cytosolic Ca(2+) in single neurons isolated from the PVN, predominantly in NUCB2/nesftin-1-immunoreactive neurons. Treatment with leptin in vivo and in vitro markedly increased NUCB2 mRNA expression in the PVN. Peripheral and central injections of leptin failed to significantly inhibit food intake in mice receiving AAV-NUCB2. These results indicate that PVN NUCB2/nesfatin-1 is directly targeted by leptin, and mediates its anorexigenic effect.


Assuntos
Anorexia/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Ligação a DNA/metabolismo , Leptina/farmacologia , Proteínas do Tecido Nervoso/metabolismo , Núcleo Hipotalâmico Paraventricular/metabolismo , Animais , Anorexia/genética , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação a DNA/genética , Dependovirus/metabolismo , Metabolismo Energético/efeitos dos fármacos , Comportamento Alimentar/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Homeostase/efeitos dos fármacos , Leptina/administração & dosagem , Masculino , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/genética , Neurônios/metabolismo , Nucleobindinas , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo
6.
World J Gastroenterol ; 20(43): 16227-35, 2014 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-25473177

RESUMO

AIM: To investigate the mechanism and in vivo effects of MK-0626, a dipeptidyl peptidase-4 inhibitor, on hepatic steatosis using ob/ob mice. METHODS: We analyzed obese (ob/ob) 8-wk-old male mice that had been randomly divided into two groups of ob/ob mice (n = 16 each) and were treated with 1.5 or 3 mg/kg MK-0626 and two control groups of untreated ob/ob mice and lean littermates (n = 16 each). All mice were fed a normal chow diet with or without MK-0626 for either four or eight weeks. Blood samples were collected, and total hepatectomy was performed. RESULTS: The administration of dietary MK-0626 ameliorated the hepatic lipid accumulation in ob/ob mice treated with 3 mg/kg MK-0626 (3 MK), P < 0.05, vs untreated ob/ob mice (ob/ob). The MK-0626 treatment reduced the serum alanine aminotransferase levels (both treatment groups, P < 0.05 vs ob/ob) and glucoses/insulin levels/calculated HOMA scores (1.5 MK, P < 0.05 vs ob/ob; 3 MK, P < 0.01 vs ob/ob) and increased the serum adiponectin levels (3 MK, P < 0.05 vs ob/ob) in a dose-dependent manner. The MK-0626 treatment increased the mRNA expression of peroxisome proliferator-activated receptor α/microsomal triglyceride transfer protein (1.5 MK, P < 0.05 vs ob/ob; 3 MK, P < 0.01 vs ob/ob) but reduced the sterol regulatory element binding transcription factor-1c/fatty acid synthase/stearoyl-CoA desaturase-1 (both treatment groups, P < 0.01 vs ob/ob). The MK-0626 treatment increased the activity of AMP-activated protein kinase (AMPK) (both treatment groups, P < 0.01 vs ob/ob). CONCLUSION: MK-0626 could attenuate hepatic steatosis through enhancing AMPK activity, inhibiting hepatic lipogenic gene expression, enhancing triglyceride secretion from liver and increasing serum adiponectin levels.


Assuntos
Dipeptidil Peptidase 4/metabolismo , Inibidores da Dipeptidil Peptidase IV/farmacologia , Fígado Gorduroso/prevenção & controle , Fígado/efeitos dos fármacos , Obesidade/tratamento farmacológico , Triazóis/farmacologia , Proteínas Quinases Ativadas por AMP/metabolismo , Adiponectina/sangue , Animais , Biomarcadores/sangue , Citoproteção , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Ativação Enzimática , Fígado Gorduroso/sangue , Fígado Gorduroso/enzimologia , Fígado Gorduroso/etiologia , Fígado Gorduroso/genética , Fígado Gorduroso/patologia , Regulação da Expressão Gênica , Lipogênese/efeitos dos fármacos , Lipogênese/genética , Fígado/enzimologia , Fígado/patologia , Masculino , Camundongos Obesos , Obesidade/sangue , Obesidade/complicações , Obesidade/enzimologia , Obesidade/genética , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Triglicerídeos/sangue
7.
Endocrinology ; 155(9): 3459-72, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25004093

RESUMO

Obesity arises from impaired energy balance, which is centrally coordinated by leptin through activation of the long form of leptin receptor (Leprb). Obesity causes central leptin resistance. However, whether enhanced peripheral leptin sensitivity could overcome central leptin resistance remains obscure. A peripheral metabolic organ targeted by leptin is the liver, with low Leprb expression. We here show that mice fed a high-fat diet (HFD) and obese patients with hepatosteatosis exhibit increased expression of hepatic helicase with zinc finger 2, a transcriptional coactivator (Helz2), which functions as a transcriptional coregulator of several nuclear receptors, including peroxisome proliferator-activated receptor γ in vitro. To explore the physiological importance of Helz2, we generated Helz2-deficient mice and analyzed their metabolic phenotypes. Helz2-deficient mice showing hyperleptinemia associated with central leptin resistance were protected against HFD-induced obesity and had significantly up-regulated hepatic Leprb expression. Helz2 deficiency and adenovirus-mediated liver-specific exogenous Leprb overexpression in wild-type mice significantly stimulated hepatic AMP-activated protein kinase on HFD, whereas Helz2-deficient db/db mice lacking functional Leprb did not. Fatty acid-ß oxidation was increased in Helz2-deficeint hepatocytes, and Helz2-deficient mice revealed increased oxygen consumption and decreased respiratory quotient in calorimetry analyses. The enhanced hepatic AMP-activated protein kinase energy-sensing pathway in Helz2-deficient mice ameliorated hyperlipidemia, hepatosteatosis, and insulin resistance by reducing lipogenic gene expression and stimulating lipid-burning gene expression in the liver. These findings together demonstrate that Helz2 deficiency ameliorates HFD-induced metabolic abnormalities by stimulating endogenous hepatic Leprb expression, despite central leptin resistance. Hepatic HELZ2 might be a novel target molecule for the treatment of obesity with hepatosteatosis.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Fígado/metabolismo , Obesidade/enzimologia , Obesidade/prevenção & controle , RNA Helicases/deficiência , Receptores para Leptina/genética , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Fígado Gorduroso/enzimologia , Feminino , Humanos , Insulina/metabolismo , Leptina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/genética , Obesidade/metabolismo , RNA Helicases/genética , Receptores para Leptina/metabolismo , Regulação para Cima
8.
Biochem Biophys Res Commun ; 451(1): 24-9, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25019984

RESUMO

Emerging evidence has indicated that the transcription and processing of precursor mRNA (pre-mRNA) are functionally coupled to modulate gene expression. In collaboration with coregulators, several steroid hormone receptors have previously been shown to directly affect alternative pre-mRNA splicing coupled to hormone-induced gene transcription; however, the roles of the thyroid hormone receptor (TR) and its coregulators in alternative splicing coordinated with transcription remain unknown. In the present study, we constructed a luciferase reporter and CD44 alternative splicing (AS) minigene driven by a minimal promoter carrying 2 copies of the palindromic thyroid hormone-response element. We then examined whether TR could modulate pre-mRNA processing coupled to triiodothyronine (T3)-induced gene transcription using luciferase reporter and splicing minigene assays in HeLa cells. In the presence of cotransfected TRß1, T3 increased luciferase activities along with the inclusion of the CD44 variable exons 4 and 5 in a dose- and time-dependent manner. In contrast, cotransfected TRß1 did not affect the exon-inclusion of the CD44 minigene driven by the cytomegalovirus promoter. T3-induced two-exon inclusion was significantly increased by the cotransfection of the TR-associated protein, 150-kDa, a subunit of the TRAP/Mediator complex that has recently been shown to function as a splicing factor. In contrast, T3-induced two-exon inclusion was significantly decreased by cotransfection of the polypyrimidine tract-binding protein-associated splicing factor, which was previously shown to function as a corepressor of TR. These results demonstrated that liganded TR in cooperation with its associating cofactors could modulate alternative pre-mRNA splicing coupled to gene transcription.


Assuntos
Processamento Alternativo , Receptores dos Hormônios Tireóideos/genética , Elementos de Resposta , Transcrição Gênica , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Éxons , Células HeLa/efeitos dos fármacos , Humanos , Receptores de Hialuronatos/genética , Luciferases/genética , Fator de Processamento Associado a PTB , Regiões Promotoras Genéticas , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Receptores dos Hormônios Tireóideos/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Tri-Iodotironina/farmacologia
9.
Endocr J ; 61(5): 523-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24705589

RESUMO

Previously we reported that the phosphorylation of Synip on serine 99 is required for Synip dissociation from Syntaxin4 and insulin-stimulated Glut4 translocation in cultured 3T3-L1 adipocytes. We also reported that the dissociated Synip remains anchored to the plasma membrane by binding to Phosphatidylinositol (3,4,5)-triphosphate. Recently Synip was reported to arrest SNARE-dependent membrane fusion as a selective t-SNARE binding inhibitor. In this study, we have found that Synip is expressed in podocytes although at a somewhat lower level than in adipocytes. To determine whether phosphorylation of Synip on serine 99 is required for insulin-stimulated Glut4 translocation and glucose uptake in podocytes we expressed a phosphorylation deficient Synip mutant (S99A-Synip) that inhibited insulin-stimulated Glut4 translocation and 2-deoxyglucose uptake in adipocytes. We conclude that serine 99 phosphorylation of Synip is required for Glut4 translocation and glucose uptake in both adipocytes and podocytes, suggesting that defects in Synip phosphorylation may underlie insulin resistance and associated diabetic nephropathy.


Assuntos
Transportador de Glucose Tipo 4/metabolismo , Glucose/metabolismo , Insulina/farmacologia , Podócitos/efeitos dos fármacos , Podócitos/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Células Cultivadas , Camundongos , Proteína Oncogênica v-akt/metabolismo , Fosforilação , Processamento de Proteína Pós-Traducional , Transporte Proteico/efeitos dos fármacos , Proteínas de Transporte Vesicular/genética
10.
PLoS One ; 8(11): e79985, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24244587

RESUMO

Ovarian cancer G protein-coupled receptor 1 (OGR1) stimulation by extracellular protons causes the activation of G proteins and subsequent cellular functions. However, the physiological and pathophysiological roles of OGR1 in airway responses remain largely unknown. In the present study, we show that OGR1-deficient mice are resistant to the cardinal features of asthma, including airway eosinophilia, airway hyperresponsiveness (AHR), and goblet cell metaplasia, in association with a remarkable inhibition of Th2 cytokine and IgE production, in an ovalbumin (OVA)-induced asthma model. Intratracheal transfer to wild-type mice of OVA-primed bone marrow-derived dendritic cells (DCs) from OGR1-deficient mice developed lower AHR and eosinophilia after OVA inhalation compared with the transfer of those from wild-type mice. Migration of OVA-pulsed DCs to peribronchial lymph nodes was also inhibited by OGR1 deficiency in the adoption experiments. The presence of functional OGR1 in DCs was confirmed by the expression of OGR1 mRNA and the OGR1-sensitive Ca(2+) response. OVA-induced expression of CCR7, a mature DC chemokine receptor, and migration response to CCR7 ligands in an in vitro Transwell assay were attenuated by OGR1 deficiency. We conclude that OGR1 on DCs is critical for migration to draining lymph nodes, which, in turn, stimulates Th2 phenotype change and subsequent induction of airway inflammation and AHR.


Assuntos
Asma/imunologia , Hiper-Reatividade Brônquica/imunologia , Células Dendríticas/imunologia , Eosinofilia Pulmonar/imunologia , Receptores Acoplados a Proteínas G/imunologia , Transferência Adotiva , Animais , Asma/induzido quimicamente , Asma/genética , Asma/patologia , Hiper-Reatividade Brônquica/induzido quimicamente , Hiper-Reatividade Brônquica/genética , Hiper-Reatividade Brônquica/patologia , Cálcio/metabolismo , Movimento Celular , Células Dendríticas/patologia , Células Dendríticas/transplante , Feminino , Regulação da Expressão Gênica , Células Caliciformes/imunologia , Células Caliciformes/patologia , Imunoglobulina E/genética , Imunoglobulina E/imunologia , Pulmão/imunologia , Pulmão/patologia , Linfonodos/imunologia , Linfonodos/patologia , Camundongos , Camundongos Knockout , Ovalbumina , Eosinofilia Pulmonar/induzido quimicamente , Eosinofilia Pulmonar/genética , Eosinofilia Pulmonar/patologia , Receptores CCR7/genética , Receptores CCR7/imunologia , Receptores Acoplados a Proteínas G/deficiência , Receptores Acoplados a Proteínas G/genética , Transdução de Sinais , Equilíbrio Th1-Th2 , Células Th2/imunologia , Células Th2/patologia
11.
BMC Cancer ; 13: 482, 2013 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-24131658

RESUMO

BACKGROUND: The expression of L-type amino acid transporter 1 (LAT1) has been described to play essential roles in tumor cell growth and survival. However, it remains unclear about the clinicopathological significance of LAT1 expression in biliary tract cancer. This study was conducted to determine biological significance of LAT1 expression and investigate whether LAT1 could be a prognostic biomarker for biliary tract cancer. METHODS: A total of 139 consecutive patients with resected pathologic stage I-IV biliary tract adenocarcinoma were retrospectively reviewed. Tumor specimens were stained by immunohistochemistry for LAT1, Ki-67, microvessel density determined by CD34, and p53; and prognosis of patients was correlated. Biological significance of LAT1 expression was investigated by in vitro and in vivo experiments with LAT inhibitor, 2-aminobicyclo-(2,2,1)-heptane-2-carboxylic acid (BCH) using cholangiocarcinoma cell line. RESULTS: In total patients, high LAT1 expressions were recognized in 64.0%. The expression of LAT1 was closely correlated with lymphatic metastases, cell proliferation and angiogenesis, and was a significant indicator for predicting poor outcome after surgery. LAT1 expression was a significant independent predictor by multivariate analysis. Both in vitro and in vivo preliminary experiments indicated that BCH significantly suppressed growth of the tumor and yielded an additive therapeutic efficacy to gemcitabine and 5-FU. CONCLUSIONS: High expression of LAT1 is a promising pathological marker to predict the outcome in patients with biliary tract adenocarcinoma. Inhibition of LAT1 may be an effective targeted therapy for this distressing disease.


Assuntos
Adenocarcinoma/metabolismo , Neoplasias do Sistema Biliar/metabolismo , Biomarcadores Tumorais/metabolismo , Transportador 1 de Aminoácidos Neutros Grandes/metabolismo , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/mortalidade , Adenocarcinoma/secundário , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Antimetabólitos Antineoplásicos/farmacologia , Neoplasias do Sistema Biliar/tratamento farmacológico , Neoplasias do Sistema Biliar/mortalidade , Neoplasias do Sistema Biliar/patologia , Linhagem Celular Tumoral , Proliferação de Células , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Intervalo Livre de Doença , Feminino , Fluoruracila/farmacologia , Proteína-1 Reguladora de Fusão/metabolismo , Humanos , Estimativa de Kaplan-Meier , Metástase Linfática , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Análise Multivariada , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto , Gencitabina
12.
Biochem Biophys Res Commun ; 439(3): 357-62, 2013 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-23998930

RESUMO

Cysteinyl leukotrienes (cysLTs), which include leukotriene C4 (LTC4), are the predominant class of LTs synthesized by mast cells. CysLTs can induce many of the abnormalities seen in asthma. LTC4 is generated by the conjugation of LTA4 with reduced glutathione (GSH) by LTC4 synthase. During screening of the effects of prostanoids on high-affinity IgE receptor (FcεRI)-mediated LTC4 release from mast cells, we realized that some prostanoids, including ONO-AE1-259-01 and ONO-AE-248, inhibited LTC4 release, which was associated with a decrease in the amount of intracellular total GSH. We ascertained that l-buthionine-S,R-sulfoximine (BSO), a selective inhibitor of glutamate-cysteine ligase, inhibited LTC4 release. In addition, cell-permeable GSH, the glutathione reduced form ethyl ester (GSH-OEt), enhanced LTC4 release in accordance with the change in intracellular total GSH. Depletion of intracellular total GSH induced by ONO-AE-248 or BSO enhanced FcεRI-mediated LTB4 release in contrast to LTC4. Oxidative stress contributes to many pathological conditions including asthma. GSH is a major soluble antioxidant and a cofactor for several detoxifying enzymes including GSH peroxidase. Exposure of mast cells to hydrogen peroxide (H2O2) or diamide to mimic oxidative stress unexpectedly increased rather than decreased the intracellular reduced GSH content as well as total GSH in the late phase (i.e., 24 or 48 h after exposure), which was accompanied by an increase in LTC4 release. In conclusion, FcεRI-mediated LTC4 release from mast cells is mainly regulated by the amount of intracellular GSH. In some cases, oxidative stress may induce a late-phase increase in intracellular GSH, resulting in enhanced LTC4 release from mast cells.


Assuntos
Glutationa/metabolismo , Leucotrieno C4/metabolismo , Mastócitos/metabolismo , Estresse Oxidativo , Receptores de IgE/metabolismo , Animais , Basófilos/imunologia , Basófilos/metabolismo , Linhagem Celular , Células Cultivadas , Glutationa/imunologia , Humanos , Peróxido de Hidrogênio/imunologia , Peróxido de Hidrogênio/metabolismo , Leucotrieno C4/imunologia , Mastócitos/imunologia , Camundongos , Prostaglandinas/imunologia , Prostaglandinas/metabolismo , Receptores de IgE/imunologia
13.
Acta Gastroenterol Belg ; 76(2): 219-24, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23898559

RESUMO

BACKGROUND: Carbon dioxide (CO2) insufflation has been shown to reduce the procedure-related pain and discomfort during colonoscopy. However, the effects of CO2 insufflation on the improvement of participant's stress had not been objectively analyzed. METHODS: Using a randomized, double-blinded design, 100 consecutive patients undergoing colonoscopy were assigned to have their examination performed with either CO2 or air insufflation. Patients completed a questionnaire to grade their discomfort using a visual analogue scale (VAS). The salivary alpha-amylase (SAA) level was also measured at these times as a marker of stress. RESULTS: The total VAS score did not show any statistically significant differences between the CO2 and air insufflation groups. However, the VAS score for abdominal fullness significantly decreased in the CO2 insufflation group in comparison to the air insufflation group in the patients who had a longer examination. The titer of the maximum SAA was significantly increased by colonoscopy (P <0.01). CO2 insufflation significantly reduced the total SAA after the colonoscopy in comparison with air insufflation (P < 0.05). The examination time and SAA tended to have a positive relationship in the air insuflation group. However, no such relationship was observed in the CO2 insufflation group. CONCLUSIONS: CO2 insufflation significantly reduced the post-examination discomfort, as indicated by a salivary stress marker. The use of CO, rather than air insufflation reduced the patients' stress and may contribute to better acceptance of colonoscopy. The usefulness of CO2 insufflation was more prominent when a longer examination was necessary.


Assuntos
Dióxido de Carbono/administração & dosagem , Colonoscopia/métodos , Insuflação/métodos , Manejo da Dor/métodos , Saliva/enzimologia , alfa-Amilases Salivares/análise , Estresse Psicológico/enzimologia , Adulto , Idoso , Biomarcadores/análise , Colonoscopia/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor , Estudos Prospectivos , Estresse Psicológico/etiologia , Estresse Psicológico/prevenção & controle , Inquéritos e Questionários
14.
Neurosci Lett ; 551: 39-42, 2013 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-23872089

RESUMO

Nesfatin-1 is a neuropeptide localized in hypothalamic paraventricular nucleus (PVN). Previously, we have reported the mechanism of feeding suppression by nesfatin-1, and also reported the ability of nesfatin-1 in regulating stress response and the circadian feeding pattern. Pituitary adenylate cyclase-activating polypeptide (PACAP) is a neuropeptide also related to the stress response, feeding, and regulation of cardiovascular and autonomic nervous systems. The neurons with receptors for PACAP are distributed in PVN. However, there are no reports showing the direct effect of PACAP on nesfatin-1 neurons. In order to explore the direct effect of PACAP on PVN nesfatin-1 neuron, we have measured the cytosolic free calcium ([Ca(2+)]i) using fura-2 microfluorometry in single neurons isolated from PVN of adult rats, followed by immunocytochemical identification of nesfatin-1 neurons. PACAP at 10(-15)M to 10(-9)M increased [Ca(2+)]i in dose dependent manner. PAC1 and VPAC2 receptor agonists also increased [Ca(2+)]i. Sixteen out of 40 neurons (40%) in PVN responded to 10(-9)M PACAP, and 12 out of 16 neurons (75%) which responded to 10(-9)M PACAP were found to be nesfatin-1 neurons. In this paper we show that PACAP directly activates nesfatin-1 neurons in PVN. The data suggest that nesfatin-1 controls feeding, stress response or autonomic response under PACAP regulation.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Núcleo Hipotalâmico Paraventricular/metabolismo , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/farmacologia , Animais , Cálcio/metabolismo , Células Cultivadas , Masculino , Neurônios/efeitos dos fármacos , Nucleobindinas , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , Ratos
15.
Intern Med ; 52(10): 1067-71, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23676592

RESUMO

Cardiovascular complications, including cardiomegaly, myocardial ischemia and left ventricular hypertrophy, are some of the major determinants of the mortality rate in patients with Cushing's syndrome. We herein report the case of a patient with Cushing's syndrome caused by an adrenal adenoma who presented with congestive heart failure secondary to dilated cardiomyopathy. Follow-up echocardiography showed a marked improvement in the left ventricular cardiac function, and the plasma B-type natriuretic peptide (BNP) levels regressed after successful treatment. "Reversible" dilated cardiomyopathy is rarely associated with Cushing's syndrome; however, it should be recognized. Administering appropriate treatment in a timely manner can reverse this cardiomyopathy along with the other symptoms of Cushing's syndrome.


Assuntos
Adenoma/complicações , Neoplasias do Córtex Suprarrenal/complicações , Cardiomiopatia Dilatada/etiologia , Síndrome de Cushing/complicações , Insuficiência Cardíaca/etiologia , Adenoma/cirurgia , Neoplasias do Córtex Suprarrenal/cirurgia , Adrenalectomia , Idoso , Biomarcadores , Cardiomiopatia Dilatada/sangue , Fármacos Cardiovasculares/uso terapêutico , Ritmo Circadiano , Síndrome de Cushing/diagnóstico , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/etiologia , Feminino , Hemoglobinas Glicadas/análise , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Hidrocortisona/sangue , Hidrocortisona/urina , Peptídeo Natriurético Encefálico/sangue , Indução de Remissão
16.
Endocr J ; 60(9): 1035-45, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23719846

RESUMO

Thyroxine (T4) needs to be converted to 3,5,3'-triiodothyronine (T3) by iodothyronine deiodinase to exert its biological activity. Recent studies revealed the presence of type 2 iodothyronine deiodinase (D2) in human thyroid tissue, human skeletal muscle and other tissues, suggesting that D2 is involved in maintaining plasma T3 level in human. Tumor necrosis factor α (TNFα) is an inflammatory cytokine of which production is elevated in patients with nonthyroidal illness. Although several lines of evidence suggest the causal role of TNFα in nonthyroidal illness, detailed nature of the effect of TNFα on D2 remains unclear. In the present study, we identified D2 activity and D2 mRNA in TCO-1 cells, which were derived from human anaplastic thyroid carcinoma, and studied the mechanisms involved in the regulation of D2 expression by TNFα. The characteristics of the deiodinating activity in TCO-1 cells were compatible with those of D2 and Northern analysis demonstrated that D2 mRNA was expressed in TCO-1cells. D2 activity and D2 mRNA expression were rapidly increased by dibutyryl cAMP ((Bu)2cAMP). TNFα showed an inhibitory effect on (Bu)2cAMP-stimulated D2 activity in spite of little effect on (Bu)2cAMP-stimulated D2 mRNA expression. MG132, a proteasome inhibitor abolished TNFα suppression of D2 activity whereas BAY11-7082 or 6-amino-4-(4-phenoxyphenylethylamino) quinazoline, inhibitors of nuclear factor-κB (NF-κB) failed to attenuate the effect of TNFα on D2 activity. These data suggest that a posttranslational mechanism through proteasomal degradation but not NF-κB activation is involved in the suppression of D2 by TNFα.


Assuntos
Iodeto Peroxidase/antagonistas & inibidores , Complexo de Endopeptidases do Proteassoma/metabolismo , Glândula Tireoide/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Bucladesina/antagonistas & inibidores , Bucladesina/farmacologia , Linhagem Celular Tumoral , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Iodeto Peroxidase/genética , Iodeto Peroxidase/metabolismo , Leupeptinas/farmacologia , Subunidade p50 de NF-kappa B/antagonistas & inibidores , Subunidade p50 de NF-kappa B/metabolismo , Complexo de Endopeptidases do Proteassoma/efeitos dos fármacos , Inibidores de Proteassoma/farmacologia , Estabilidade Proteica/efeitos dos fármacos , Proteólise/efeitos dos fármacos , RNA Mensageiro/metabolismo , Proteínas Recombinantes/metabolismo , Sistemas do Segundo Mensageiro/efeitos dos fármacos , Glândula Tireoide/efeitos dos fármacos , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/genética , Iodotironina Desiodinase Tipo II
17.
Lab Invest ; 93(6): 720-32, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23608755

RESUMO

The role that transforming growth factor-α (TGF-α) has in chronic pancreatitis and pancreatic cancer has not been fully elucidated. We evaluated the effects of TGF-α on the human pancreatic stellate cell (PSC) line RLT-PSC and primary human PSCs, and the expression levels of TGF-α and metalloproteinase-1 (MMP-1) in human chronic pancreatitis and pancreatic cancer tissues. TGF-α stimulated the proliferation and migration of PSCs. Although the mRNA expression levels of tissue inhibitor of metalloproteinase-1 and α1(I) collagen were unchanged, the mRNA expression levels of MMP-1 increased concomitant with increases in MMP-1 protein levels and collagenase activity. TGF-α-stimulated migration of RLT-PSC cells was partially blocked by tissue inhibitor of metalloproteinase-1 protein and MMP-1 small interfering RNA. MMP-1 was also observed to stimulate the migration of PSCs. TGF-α-induced MMP-1 expression was completely blocked by gefitinib in PSCs. The Ras-ERK and PI3/Akt pathways appear to be involved in the activation of MMP-1 in PSCs. Immunohistochemical analyses showed that MMP-1 expression was significantly increased in the pancreatic interstitial tissues in case of chronic pancreatitis or pancreatic cancer compared with those in case of normal pancreas. In conclusion, TGF-α increased proliferation and migration of PSCs. TGF-α-induced migration of cells may be partly due to upregulation of MMP-1. TGF-α and MMP-1 upregulation may contribute to the pathogenesis of chronic pancreatitis and pancreatic cancer.


Assuntos
Metaloproteinase 1 da Matriz/metabolismo , Neoplasias Pancreáticas/metabolismo , Células Estreladas do Pâncreas/metabolismo , Pancreatite Crônica/metabolismo , Fator de Crescimento Transformador alfa/metabolismo , Actinas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular , Proliferação de Células , Sobrevivência Celular , Receptores ErbB/metabolismo , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Humanos , Sistema de Sinalização das MAP Quinases , Masculino , Pessoa de Meia-Idade , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Proteínas ras/metabolismo
18.
Gastroenterol Res Pract ; 2013: 168012, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23533384

RESUMO

Background. The study aims to analyze in detail the incidence, mortality using the standardized incidence ratio (SIR), and standardized mortality ratio (SMR) of hepatocellular carcinoma (HCC) in primary biliary cirrhosis (PBC), because no large case studies have focused on the detailed statistical analysis of them in Asia. Methods. The study cohorts were consecutively diagnosed at Gunma University and its affiliated hospitals. Age- or sex-specific annual cancer incidence and deaths were obtained from Japanese Cancer Registry and Death Registry as a reference for the comparison of SIR or SMR of HCC. Moreover, univariate analyses and multivariate analyses were performed to clarify predictive factors for the incidence of HCC. Results. The overall 179 patients were followed up for a median of 97 months. HCC had developed in 13 cases. SIR for HCC was 11.6 (95% confidence interval (CI), 6.2-19.8) and SMR for HCC was 11.2 (95% CI, 5.4-20.6) in overall patients. The serum albumin levels were a predictive factor for the incidence of HCC in overall patients. Conclusions. The incidence and mortality of HCC in PBC patients were significantly higher than those in Japanese general population. PBC patients with low serum albumin levels were populations at high risk for HCC.

19.
Anticancer Res ; 33(3): 895-901, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23482759

RESUMO

BACKGROUND: Hepatocyte growth factor (HGF) was initially discovered as a mitogen for hepatocytes, but it is also known to be related to carcinogenesis in many other organs. However, the role of HGF in lung carcinogenesis is not fully-understood. In this study, we investigated the role of HGF in lung carcinogenesis using HGF transgenic mice. MATERIALS AND METHODS: To elucidate the role of HGF in lung carcinogenesis, 5 µg/g body weight diethylnitrosamine (DEN) were administered intraperitoneally to HGF transgenic (TG) mice and wild-type (WT) mice at 15 days of age. The incidence and number of lung tumors, the expression of HGF and of its receptor (c-Met) were compared between HGF TG and WT mice. RESULTS: HGF overexpression accelerated DEN-induced lung carcinogenesis. Seventy-six percent of TG mice (versus 50% of WT mice) developed malignant lung tumors by 48 weeks. The incidence of lung tumors was significantly higher in the TG mice in comparison with WT mice (p<0.05). Furthermore, the mean diameter and number of tumors in each mouse were significantly higher in the TG mice compared to the WT mice (p<0.01). The northern blotting analyses revealed that there was overexpression of the HGF transgene in the lung tumors of TG mice in comparison with the surrounding non-tumorous lesions. The western blotting analyses of the tumor lesions revealed increased phosphorylation of c-Met. CONCLUSION: Our results suggest that HGF promotes lung carcinogenesis through the autocrine activation of the HGF/c-Met signaling pathway. The HGF/c-Met signaling pathway appears to have vital roles in lung carcinogenesis.


Assuntos
Fator de Crescimento de Hepatócito/fisiologia , Neoplasias Pulmonares/induzido quimicamente , Animais , Dietilnitrosamina , Feminino , Fator de Crescimento de Hepatócito/genética , Masculino , Camundongos , Camundongos Transgênicos , Proteínas Proto-Oncogênicas c-met/análise , Proteínas Proto-Oncogênicas c-met/fisiologia
20.
Acta Med Okayama ; 67(1): 45-53, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23439508

RESUMO

In patients with nonalcoholic steatohepatitis (NASH), the prevalence of cirrhosis is higher among women than men, and hepatocellular carcinoma (HCC) develops mainly in the cirrhotic stage among women. However, the long-term outcomes in female patients with NASH have not been fully elucidated, and age, gender and BMI were not simultaneously adjusted in previous studies on the prognosis of NASH. To elucidate the outcomes in female patients with NASH, we prospectively compared NASH patients with advanced fibrosis (advanced NASH) with hepatitis C virus-related advanced fibrosis (advanced CHC) patients and NASH patients with mild fibrosis (mild NASH) using study cohorts that were adjusted for body mass index (BMI) in addition to age. The median follow-up period was 92.5 months. Liver-related complication-free survival was significantly reduced in the advanced NASH group compared to the mild NASH group. No liver-related complications developed in the mild NASH group. The overall survival, liver-related complication- and cardiovascular/cerebrovascular disease-free survival were not significantly different between the advanced NASH and CHC groups. Female patients with NASH and advanced fibrosis may have a less favorable prognosis for liver-related complications than the matched cohorts with NASH and mild fibrosis, but may have a similar prognosis to the matched cohorts with CHC.


Assuntos
Índice de Massa Corporal , Fígado Gorduroso/mortalidade , Idoso , Idoso de 80 Anos ou mais , Doenças Cardiovasculares/mortalidade , Estudos de Coortes , Fígado Gorduroso/complicações , Feminino , Hepatite C Crônica/complicações , Humanos , Cirrose Hepática/etiologia , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica , Prognóstico , Estudos Prospectivos
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