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1.
PLoS One ; 15(1): e0228212, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31990961

RESUMO

Acetyl-CoA carboxylase (ACC) catalyzes the rate-limiting step in de novo lipogenesis, which is increased in the livers of patients with nonalcoholic steatohepatitis. GS-0976 (firsocostat), an inhibitor of isoforms ACC1 and ACC2, reduced hepatic steatosis and serum fibrosis biomarkers such as tissue inhibitor of metalloproteinase 1 in patients with nonalcoholic steatohepatitis in a randomized controlled trial, although the impact of this improvement on fibrosis has not fully been evaluated in preclinical models. Here, we used Western diet-fed melanocortin 4 receptor-deficient mice that have similar phenotypes to nonalcoholic steatohepatitis patients including progressively developed hepatic steatosis as well as fibrosis. We evaluated the effects of ACC1/2 inhibition on hepatic fibrosis. After the confirmation of significant hepatic fibrosis with a 13-week pre-feeding, GS-0976 (4 and 16 mg/kg/day) treatment for 9 weeks lowered malonyl-CoA and triglyceride content in the liver and improved steatosis, histologically. Furthermore, GS-0976 reduced the histological area of hepatic fibrosis, hydroxyproline content, mRNA expression level of type I collagen in the liver, and plasma tissue metalloproteinase inhibitor 1, suggesting an improvement of hepatic fibrosis. The treatment with GS-0976 was also accompanied by reductions of plasma ALT and AST levels. These data demonstrate that improvement of hepatic lipid metabolism by ACC1/2 inhibition could be a new option to suppress fibrosis progression as well as to improve hepatic steatosis in nonalcoholic steatohepatitis.


Assuntos
Acetil-CoA Carboxilase/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Técnicas de Inativação de Genes , Cirrose Hepática/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Receptor Tipo 4 de Melanocortina/deficiência , Receptor Tipo 4 de Melanocortina/genética , Animais , Modelos Animais de Doenças , Inibidores Enzimáticos/uso terapêutico , Isobutiratos/farmacologia , Isobutiratos/uso terapêutico , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Camundongos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Tamanho do Órgão/efeitos dos fármacos , Oxazóis/farmacologia , Oxazóis/uso terapêutico , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Triglicerídeos/metabolismo
2.
J Immunol Methods ; 480: 112751, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31982420

RESUMO

Intracellular DNA triggers interferon release during the innate immune response. Cyclic GMP-AMP synthase (cGAS) senses intracellular double-stranded DNA not only in response to viral infection but also under autoimmune conditions. Measuring the levels of cyclic GMP-AMP (cGAMP) as a second messenger of cGAS activation is important to elucidate the physiological and pathological roles of cGAS. Therefore, we generated monoclonal antibodies against cGAMP using hybridoma technology to test antibody specificity and establish methods to detect intracellular cGAMP. The resulting cGAMP-specific antibody enabled the development of a time-resolved fluorescence energy transfer assay with a quantifiable range of 0.1 nM to 100 nM cGAMP. Using this assay, we detected cellular and tissue cGAMP. We confirmed that the cGAMP antibody successfully targeted intracellular cGAMP through immunocytochemical analyses. These results demonstrated that the cGAMP antibody is a powerful tool that allows determining cGAS involvement in autoimmunity and disease pathology at the cell and tissue levels.


Assuntos
Anticorpos Monoclonais/imunologia , Doenças Autoimunes do Sistema Nervoso/metabolismo , Transferência Ressonante de Energia de Fluorescência , Imuno-Histoquímica , Neoplasias/metabolismo , Malformações do Sistema Nervoso/metabolismo , Nucleotídeos Cíclicos/metabolismo , Nucleotidiltransferases/metabolismo , Animais , Especificidade de Anticorpos , Doenças Autoimunes do Sistema Nervoso/genética , Doenças Autoimunes do Sistema Nervoso/imunologia , Autoimunidade , Biomarcadores/metabolismo , Células CACO-2 , Modelos Animais de Doenças , Ativação Enzimática , Exodesoxirribonucleases/deficiência , Exodesoxirribonucleases/genética , Células HEK293 , Células HL-60 , Ensaios de Triagem em Larga Escala , Humanos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neoplasias/imunologia , Malformações do Sistema Nervoso/genética , Malformações do Sistema Nervoso/imunologia , Nucleotídeos Cíclicos/imunologia , Nucleotidiltransferases/genética , Fosfoproteínas/deficiência , Fosfoproteínas/genética , Valor Preditivo dos Testes , Reprodutibilidade dos Testes
3.
EBioMedicine ; 45: 362-378, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31262712

RESUMO

BACKGROUND: The characteristic structure of motor neurons (MNs), particularly of the long axons, becomes damaged in the early stages of amyotrophic lateral sclerosis (ALS). However, the molecular pathophysiology of axonal degeneration remains to be fully elucidated. METHOD: Two sets of isogenic human-induced pluripotent stem cell (hiPSCs)-derived MNs possessing the single amino acid difference (p.H517D) in the fused in sarcoma (FUS) were constructed. By combining MN reporter lentivirus, MN specific phenotype was analyzed. Moreover, RNA profiling of isolated axons were conducted by applying the microfluidic devices that enable axon bundles to be produced for omics analysis. The relationship between the target gene, which was identified as a pathological candidate in ALS with RNA-sequencing, and the MN phenotype was confirmed by intervention with si-RNA or overexpression to hiPSCs-derived MNs and even in vivo. The commonality was further confirmed with other ALS-causative mutant hiPSCs-derived MNs and human pathology. FINDINGS: We identified aberrant increasing of axon branchings in FUS-mutant hiPSCs-derived MN axons compared with isogenic controls as a novel phenotype. We identified increased level of Fos-B mRNA, the binding target of FUS, in FUS-mutant MNs. While Fos-B reduction using si-RNA or an inhibitor ameliorated the observed aberrant axon branching, Fos-B overexpression resulted in aberrant axon branching even in vivo. The commonality of those phenotypes was further confirmed with other ALS causative mutation than FUS. INTERPRETATION: Analyzing the axonal fraction of hiPSC-derived MNs using microfluidic devices revealed that Fos-B is a key regulator of FUS-mutant axon branching. FUND: Japan Agency for Medical Research and development; Japanese Ministry of Education, Culture, Sports, Science and Technology Clinical Research, Innovation and Education Center, Tohoku University Hospital; Japan Intractable Diseases (Nanbyo) Research Foundation; the Kanae Foundation for the Promotion of Medical Science; and "Inochi-no-Iro" ALS research grant.


Assuntos
Esclerose Lateral Amiotrófica/genética , Proteínas Proto-Oncogênicas c-fos/genética , Proteína FUS de Ligação a RNA/genética , Esclerose Lateral Amiotrófica/patologia , Animais , Axônios/metabolismo , Axônios/patologia , Diferenciação Celular/genética , Linhagem Celular , Edição de Genes/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Lentivirus/genética , Neurônios Motores/metabolismo , Mutação , Neurogênese/genética , Fenótipo , RNA Interferente Pequeno/genética
4.
Brain Behav ; 8(1): e00881, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29568682

RESUMO

Objectives: Bombesin receptor subtype-3 (BRS-3) has been suggested to play a potential role in energy homeostasis. However, the physiological mechanism of BRS-3 on energy homeostasis remains unknown. Thus, we investigated the BRS-3-mediated neuronal pathway involved in food intake and energy expenditure. Materials and Methods: Expression of BRS-3 in the rat brain was histologically examined. The BRS-3 neurons activated by refeeding-induced satiety or a BRS-3 agonist were identified by c-Fos immunostaining. We also analyzed expression changes in feeding-relating peptides in the brain of fasted rats administered with the BRS-3 agonist. Results: In the paraventricular hypothalamic nucleus (PVH), dorsomedial hypothalamic nucleus (DMH), and medial preoptic area (MPA), strong c-Fos induction was observed in the BRS-3 neurons especially in PVH after refeeding. However, the BRS-3 neurons in the PVH did not express feeding-regulating peptides, while the BRS-3 agonist administration induced c-Fos expression in the DMH and MPA, which were not refeeding-sensitive, as well as in the PVH. The BRS-3 agonist administration changed the Pomc and Cart mRNA level in several brain regions of fasted rats. Conclusion: These results suggest that BRS-3 neurons in the PVH are a novel functional subdivision in the PVH that regulates feeding behavior. As the MPA and DMH are reportedly involved in thermoregulation and energy metabolism, the BRS-3 neurons in the MPA/DMH might mediate the energy expenditure control. POMC and CART may contribute to BRS-3 neuron-mediated energy homeostasis regulation. In summary, BRS-3-expressing neurons could regulate energy homeostasis through a novel neuronal pathway.


Assuntos
Metabolismo Energético/fisiologia , Homeostase/fisiologia , Hipotálamo/metabolismo , Neurônios/metabolismo , Receptores da Bombesina/metabolismo , Animais , Células CHO , Cricetulus , Ingestão de Alimentos/fisiologia , Comportamento Alimentar/fisiologia , Hipotálamo/efeitos dos fármacos , Masculino , Camundongos Knockout , Proteínas do Tecido Nervoso/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores da Bombesina/agonistas , Receptores de Somatostatina/genética
5.
Eur J Pharmacol ; 796: 45-53, 2017 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-27986627

RESUMO

Melanin-concentrating hormone (MCH), a cyclic neuropeptide expressed predominantly in the lateral hypothalamus, plays an important role in the control of feeding behavior and energy homeostasis. Mice lacking MCH or MCH1 receptor are resistant to diet-induced obesity (DIO) and MCH1 receptor antagonists show potent anti-obesity effects in preclinical studies, indicating that MCH1 receptor is a promising target for anti-obesity drugs. Moreover, recent studies have suggested the potential of MCH1 receptor antagonists for treatment of non-alcoholic fatty liver disease (NAFLD). In the present study, we show the anti-obesity and anti-hepatosteatosis effect of our novel MCH1 receptor antagonist, Compound A. Repeated oral administration of Compound A resulted in dose-dependent body weight reduction and had an anorectic effect in DIO mice. The body weight lowering effect of Compound A was more potent than that of pair-feeding. Compound A also reduced lipid content and the expression level of lipogenesis-, inflammation-, and fibrosis-related genes in the liver of DIO mice. Conversely, intracerebroventricular infusion of MCH caused induction of hepatic steatosis as well as increase in body weight in high-fat diet-fed wild type mice, but not MCH1 receptor knockout mice. The pair-feeding study revealed the MCH-MCH1 receptor system affects hepatic steatosis through a mechanism that is independent of body weight change. Metabolome analysis demonstrated that Compound A upregulated lipid metabolism-related molecules, such as acylcarnitines and cardiolipins, in the liver. These findings suggest that our novel MCH1 receptor antagonist, Compound A, exerts its beneficial therapeutic effect on NAFLD and obesity through a central MCH-MCH1 receptor pathway.


Assuntos
Fármacos Antiobesidade/farmacologia , Dieta Hiperlipídica/efeitos adversos , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Obesidade/induzido quimicamente , Obesidade/tratamento farmacológico , Receptores do Hormônio Hipofisário/antagonistas & inibidores , Animais , Fármacos Antiobesidade/uso terapêutico , Peso Corporal/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Técnicas de Inativação de Genes , Lipogênese/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/metabolismo , Ratos , Receptores do Hormônio Hipofisário/deficiência , Receptores do Hormônio Hipofisário/genética
6.
J Nat Prod ; 76(11): 2034-9, 2013 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-24262004

RESUMO

A proposed structure for schizocommunin (Z)-1(hydroxy) and its geometric isomer (E)-1(hydroxy), which exist in a keto form, has been synthesized. However, the spectroscopic data of (Z)-1(keto) and (E)-1(keto) were not consistent with those reported for natural schizocommunin. After reinvestigating the spectral data for natural schizocommunin, we synthesized the quinazolinone derivative (Z)-2 as a revised structure for schizocommunin. All of the spectral data of (Z)-2 were completely identical to those reported for natural schizocommunin. (Z)-2 showed moderate antiproliferative activity.


Assuntos
Indóis/química , Indóis/síntese química , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Indóis/farmacologia , Estrutura Molecular , Estereoisomerismo , Relação Estrutura-Atividade
7.
Shokuhin Eiseigaku Zasshi ; 49(3): 141-9, 2008 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-18633198

RESUMO

The effects of processing and cooking on the levels of pesticide residues in rice samples were investigated for 11 pesticides in pre-harvest (9 pesticides) and post-harvest (4 pesticides) samples. In the polishing process, the transfer ratio (%, total pesticide residue amount in product/that in brown rice) of rice bran ranged from 40% to 106%, and the transfer ratio of polished rice ranged from 9% to 65% in pre-harvest samples. These values varied from pesticide to pesticide. The processing factor (the concentration (mg/kg) of pesticide in product/that in the brown rice) of polished rice ranged from 0.11 to 0.73. The loss of pesticides during processing and/or cooking did not correlate to any single physical or chemical property. Investigation of changes of pesticide residues during processing and/or cooking is useful not only to establish MRLs, but also to recognize actual levels of pesticide residues in food.


Assuntos
Culinária , Manipulação de Alimentos , Oryza/química , Resíduos de Praguicidas/análise , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas
8.
Shokuhin Eiseigaku Zasshi ; 49(3): 150-9, 2008 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-18633199

RESUMO

The effects of processing and cooking on the levels of pesticide residues in wheat samples were investigated for 13 pesticides in pre-harvest (Pre, 9 pesticides) and post-harvest (Post, 6 pesticides) samples. In the milling process, the transfer ratios (%, total pesticide residue amount in product/that in wheat grain) of wheat bran were greater than 70% and 80% for pre-harvest and post-harvest samples, respectively. The transfer ratios of flour ranged from 1.7% to 23% (Pre) and 4.0% to 11% (Post). There was no significant difference in transfer ratio among the pesticides investigated. The processing factors (Pf, the concentration (mg/kg) of pesticide in product/that in the wheat grain) of flour ranged from 0.030 to 0.40 (Pre) and 0.069 to 0.18 (Post). The values in pre-harvest samples were higher than those in post-harvest samples. Investigation of changes of pesticide residues during processing and/or cooking is useful not only to establish MRLs, but also to recognize actual levels of pesticide residues in food.


Assuntos
Culinária , Manipulação de Alimentos , Resíduos de Praguicidas/análise , Triticum/química , Fibras na Dieta/análise
9.
Shokuhin Eiseigaku Zasshi ; 49(3): 160-7, 2008 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-18633200

RESUMO

The effects of processing and cooking on the levels of pesticide residues in soybean samples were investigated for 14 pesticides in pre-harvest samples. On soaking, the transfer ratios (%, total pesticide residue amount in product/that in soybean) of soaked soybean were greater than 60% for most of the pesticides investigated. The transfer ratio of soymilk ranged from 37% to 92%, and that of tofu ranged from 7% to 63%. The processing factor (Pf, the concentration (mg/kg) of pesticide in product/that in soybean) of tofu ranged from 0.026 to 0.28. These values varied among pesticides. There was a high correlation between the log P(ow) and the transfer ratio of tofu. The test described here should be useful to obtain the transfer ratios of pesticide residues in processing and/or cooking steps.


Assuntos
Culinária , Manipulação de Alimentos , Glycine max/química , Resíduos de Praguicidas/análise
10.
J Org Chem ; 68(24): 9412-5, 2003 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-14629166

RESUMO

A phosphine ligand, such as PPh3 or 2-(dicyclohexylphosphino)biphenyl, is essential for the Pd/C-catalyzed Suzuki-Miyaura coupling of halopyridines and haloquinolines, although it has been reported that the reaction of phenyl chlorides can be catalyzed by nonprereduced Pd/C without any additives. In the reactions of bromopyridines, bromoquinolines, 2-chloropyridines, and 2-chloroquinolines, PPh3 was effective enough to provide coupling products in good yields. However, in the reactions of 3-chloropyridine, 4-chloropyridine, and 6-chloroquinoline, sterically hindered 2-(dicyclohexylphosphino)biphenyl was indispensable as a ligand.

11.
Neuroendocrinology ; 75(1): 2-11, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11810030

RESUMO

Our previous studies on annexin 5, a member of the annexin family of proteins, have shown its expression in the anterior pituitary gland, its preferential distribution in gonadotropes, and its increase after ovariectomy. In the present study, we examined (1) whether annexin 5 is synthesized in gonadotropes, (2) whether its expression is under the control of gonadotropin-releasing hormone (GnRH), and (3) the effect of annexin 5 on gonadotropin release. Large cells, also called castration cells, appeared in anterior pituitary tissue 3 weeks after ovariectomy. These cells have been confirmed to be hyperfunctioning gonadotropes and are easily discriminated from other pituitary cells without immunostaining. Using in situ hybridization with a digoxigenin-labeled ribonucleic acid probe, enhanced expression of annexin 5 messenger ribonucleic acid (mRNA) in these gonadotropes was clearly demonstrated. Northern blot analysis showed an increase in the level of annexin 5 mRNA expression 3 weeks after ovariectomy. It was lessened 3 h after the injection of Cetrorelix (GnRH antagonist, 10 microg i.v.). Administration of a GnRH analog [GnRHa; Des-Gly 10 (Pro9) GnRH ethylamide, 0.2 ml of 2.5 microg/ml saline ten times intraperitoneally at 30-min intervals] significantly increased pituitary annexin 5 mRNA. In primary cultures of anterior pituitary cells, recombinant rat annexin 5 stimulated luteinizing hormone (LH) and follicle-stimulating hormone (FSH) release in a dose-dependent manner. Concomitant administration of annexin 5 (1 microg/ml) and GnRHa augmented the LH and FSH release induced by GnRHa. After a 1-hour incubation, cycloheximide (10 microg/ml) apparently inhibited the LH response to GnRHa, while annexin 5 (2 microg/ml) moderated this inhibition. Further, the antisense oligodeoxynucleotide to annexin 5 mRNA blunted the LH response to GnRHa. It is thus concluded that annexin 5 is synthesized in the gonadotropes under the effect of GnRH, and it is suggested that annexin 5 synthesis mediates at least partly GnRH receptor signaling to stimulate gonadotropin secretion.


Assuntos
Anexina A5/genética , Hormônio Liberador de Gonadotropina/fisiologia , Gonadotropinas/metabolismo , Hipófise/fisiologia , Animais , Anexina A5/farmacologia , Células Cultivadas , Cicloeximida/farmacologia , Feminino , Hormônio Foliculoestimulante/metabolismo , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/fisiologia , Hormônio Liberador de Gonadotropina/farmacologia , Técnicas In Vitro , Hormônio Luteinizante/metabolismo , Oligodesoxirribonucleotídeos Antissenso , Ovariectomia , Hipófise/citologia , Inibidores da Síntese de Proteínas/farmacologia , RNA Mensageiro/análise , Ratos , Ratos Wistar
12.
Angew Chem Int Ed Engl ; 37(5): 636-637, 1998 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-29711084

RESUMO

Dry air is the source of molecular nitrogen for reactions with TiL4 , Li, and TMSCl (L = Cl, OiPr; TMS = trimethylsilyl). The nitrogen-titanium complexes thus prepared can be used to synthesize indoles, pyrroles, and lactams from carbonyl compounds. Applying this method to 1 provides access to 2, the key compound in the synthesis of (±)-lycopodine.

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