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1.
J Vet Med Sci ; 85(12): 1301-1309, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37821377

RESUMO

Transient receptor potential ankyrin 1 (TRPA1) is a nonselective cation channel that is activated by a variety of stimuli and acts as a nociceptor. Mouse and human TRPA1 exhibit different reactivity to some stimuli, including chemicals such as menthol as well as cold stimuli. The cold sensitivity of TRPA1 in mammalian species is controversial. Here, we analyzed the reactivity of heterologously expressed canine TRPA1 as well as the mouse and human orthologs to menthol or cold stimulation in Ca2+-imaging experiments. Canine and human TRPA1 exhibited a similar response to menthol, that is, activation in a concentration-dependent manner, even at the high concentration range in contrast to the mouse ortholog, which did not respond to high concentration of menthol. In addition, the response during the removal of menthol was different; mouse TRPA1-expressing cells exhibited a typical response with a rapid and clear increase in [Ca2+]i ("off-response"), whereas [Ca2+]i in human TRPA1-expressing cells was dramatically decreased by the washout of menthol and [Ca2+]i in canine TRPA1-expressing cells was slightly decreased. Finally, canine TRPA1 as well as mouse and human TRPA1 were activated by cold stimulation (below 19-20°C). The sensitivity to cold stimulation differed between these species, that is, human TRPA1 activated at higher temperatures compared with the canine and mouse orthologs. All of the above responses were suppressed by the selective TRPA1 inhibitor HC-030031. Because the concentration-dependency and "off-response" of menthol as well as the cold sensitivity were not uniform among these species, studies of canine TRPA1 might be useful for understanding the species-specific functional properties of mammalian TRPA1.


Assuntos
Canal de Cátion TRPA1 , Canais de Potencial de Receptor Transitório , Animais , Cães , Humanos , Camundongos , Temperatura Baixa , Mamíferos , Mentol/farmacologia , Canal de Cátion TRPA1/metabolismo , Canais de Cátion TRPM
2.
Heliyon ; 7(1): e06102, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33553759

RESUMO

The transient receptor potential melastatin 5 (TRPM5) channel is a monovalent-permeable cation channel that is activated by intracellular Ca2+. Expression of TRPM5 has been shown in taste cells, pancreas, brainstem and olfactory epithelium, and this channel is thought to be involved in controlling membrane potentials. In whole-cell patch-clamp recordings, TRPM5 exhibited voltage-dependent inactivation at negative membrane potentials and time constant of voltage-dependent inactivation of TRPM5 did not depend on the intracellular Ca2+ concentrations between 100 and 500 nM. Alanine substitution at Y913 and I916 in the pore helix of TRPM5 increased time constant of voltage-dependent inactivation. Meanwhile, voltage-dependent inactivation was reduced in TRPM5 mutants having glycine substitution at L901, Y913, Q915 and I916 in the pore helix. From these results, we conclude that the pore helix in the outer pore loop might play a role in voltage-dependent inactivation of TRPM5.

3.
Intern Med ; 60(3): 479-485, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33361672

RESUMO

An outbreak of coronavirus disease 2019 (COVID-19) that began in Wuhan, China, has spread rapidly to many countries. We herein report four cases of COVID-19 confirmed in Japan among passengers of the cruise ship Diamond Princess and describe the clinical features, clinical course, and progression of chest computed tomographic images, chest radiographs, and treatment. Although these four patients had symptoms that included a fever, malaise, runny nose, and cough, one patient had no symptoms on admission. Two of the four patients needed mechanical ventilation due to respiratory deterioration. One of the patients who required mechanical ventilation was transferred to a higher-level medical institution. Except for that patient, the other three patients were able to return home under their own power. Every patient took lopinavir/ritonavir, which was considered the most effective treatment at the time. We used it after receiving approval from the ethics committee in our hospital. In this case report, we emphasize that some patients need to be carefully monitored, even if their respiratory condition is stable at the initial presentation, as their respiratory status may deteriorate rapidly within a few days after oxygen administration begins.


Assuntos
COVID-19/transmissão , Navios , Idoso , Idoso de 80 Anos ou mais , COVID-19/diagnóstico , COVID-19/terapia , Teste de Ácido Nucleico para COVID-19 , Inibidores do Citocromo P-450 CYP3A/uso terapêutico , Humanos , Japão , Lopinavir/uso terapêutico , Pulmão/diagnóstico por imagem , Pulmão/patologia , Masculino , Radiografia Torácica , Respiração Artificial , Ritonavir/uso terapêutico , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação
4.
Front Immunol ; 11: 579266, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33117381

RESUMO

The pro-inflammatory cytokine interleukin 1ß (IL-1ß) induces the synthesis of prostaglandin E2 by upregulating cyclooxygenase-2 (COX-2) in the synovial tissue of individuals with autoimmune diseases, such as rheumatoid arthritis (RA). IL-1ß-mediated stimulation of NF-κB and MAPK signaling is important for the pathogenesis of RA; however, crosstalk(s) between NF-κB and MAPK signaling remains to be understood. In this study, we established a model for IL-1ß-induced synovitis and investigated the role of NF-κB and MAPK signaling in synovitis. We observed an increase in the mRNA and protein levels of COX-2 and prostaglandin E2 release in cells treated with IL-1ß. NF-κB and ERK1/2 inhibitors significantly reduced IL-1ß-induced COX-2 expression. IL-1ß induced the phosphorylation of canonical NF-κB complex (p65 and p105) and degradation of IκBα. IL-1ß also induced ERK1/2 phosphorylation but did not affect the phosphorylation levels of p38 MAPK and JNK. IL-1ß failed to induce COX-2 expression in cells transfected with siRNA for p65, p105, ERK1, or ERK2. Notably, NF-κB inhibitors reduced IL-1ß-induced ERK1/2 phosphorylation; however, the ERK1/2 inhibitor had no effect on the phosphorylation of the canonical NF-κB complex. Although transcription and translation inhibitors had no effect on IL-1ß-induced ERK1/2 phosphorylation, the silencing of canonical NF-κB complex in siRNA-transfected fibroblasts prevented IL-1ß-induced phosphorylation of ERK1/2. Taken together, our data indicate the importance of the non-transcriptional/translational activity of canonical NF-κB in the activation of ERK1/2 signaling involved in the IL-1ß-induced development of autoimmune diseases affecting the synovial tissue, such as RA.


Assuntos
Ciclo-Oxigenase 2/metabolismo , Fibroblastos/efeitos dos fármacos , Interleucina-1beta/toxicidade , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , NF-kappa B/metabolismo , Membrana Sinovial/efeitos dos fármacos , Sinovite/induzido quimicamente , Animais , Células Cultivadas , Ciclo-Oxigenase 2/genética , Cães , Ativação Enzimática , Fibroblastos/enzimologia , Fibroblastos/patologia , NF-kappa B/genética , Fosforilação , Transdução de Sinais , Membrana Sinovial/enzimologia , Membrana Sinovial/patologia , Sinovite/enzimologia , Sinovite/patologia
5.
Intern Med ; 59(23): 3089-3092, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32759588

RESUMO

Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare condition of systemic vasculitis of small to medium-sized blood vessels. We herein report the case of a 75-year-old man who presented with hemiplegia on his right side due to cerebral infarction following myalgia and a high fever. He had no history of asthma or allergic rhinitis. He was diagnosed with EGPA based on the presence of eosinophilia, sinusitis suggested by magnetic resonance imaging, and muscle pathology. His hemiplegia improved rapidly after corticosteroid therapy. This case suggests that EGPA should be a differential diagnosis of cerebral infarction with myalgia and eosinophilia.


Assuntos
Infarto Cerebral/complicações , Síndrome de Churg-Strauss/complicações , Mialgia/complicações , Idoso , Diagnóstico Diferencial , Humanos , Imageamento por Ressonância Magnética , Masculino
6.
Emerg Infect Dis ; 26(9)2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32412897

RESUMO

An autopsy of a patient in Japan with coronavirus disease indicated pneumonia lung pathology, manifested as diffuse alveolar damage. We detected severe acute respiratory syndrome coronavirus 2 antigen in alveolar epithelial cells and macrophages. Coronavirus disease is essentially a lower respiratory tract disease characterized by direct viral injury of alveolar epithelial cells.


Assuntos
Betacoronavirus , Infecções por Coronavirus/patologia , Pneumonia Viral/patologia , Idoso de 80 Anos ou mais , Células Epiteliais Alveolares/patologia , Células Epiteliais Alveolares/virologia , Autopsia , COVID-19 , Infecções por Coronavirus/virologia , Feminino , Humanos , Imuno-Histoquímica , Japão , Pulmão/patologia , Pulmão/virologia , Pandemias , Pneumonia Viral/virologia , SARS-CoV-2
7.
J Physiol Sci ; 69(4): 623-634, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31011981

RESUMO

TRPM3 is a non-selective cation channel that is activated by neural steroids such as pregnenolone sulfate, nifedipine, and clotrimazole. Despite the number of TRPM3 variants, few reports have described functional analyses of these different TRPM3 types. Here we identified a new TRPM variant from mouse dorsal root ganglion, termed TRPM3γ3. We classified TRPM3γ3 and another known variant (variant 6) into the γ subtype, and analyzed the TRPM3γ variants. mRNA expression of TRPM3γ was higher than that of TRPM3α variants in the mouse dorsal root ganglion. In Ca2+-imaging of HEK293 cells expressing either the TRPM3γ variants or TRPM3α2, increases in cytosolic Ca2+ concentrations ([Ca2+]i) induced by pregnenolone sulfate or nifedipine were smaller in cells expressing the TRPM3γ variants compared to those expressing TRPM3α2. On the other hand, co-expression of TRPM3γ variants had no effect on [Ca2+]i increases induced by pregnenolone sulfate or nifedipine treatment of HEK293 cells expressing TRPM3α2. In Xenopus oocytes, small responses of TRPM3γ variants to chemical agonists compared to TRPM3α2 were also observed. Interestingly, Xenopus oocytes expressing TRPM3α2 displayed heat-evoked currents with clear thresholds of about 40 °C that were larger than those evoked in oocytes expressing TRPM3γ variants. Overall, these findings indicate that TRPM3γ variants have low channel activity compared to TRPM3α.


Assuntos
Canais de Cátion TRPM/metabolismo , Animais , Cálcio/metabolismo , Linhagem Celular , Gânglios Espinais/metabolismo , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Oócitos/metabolismo , RNA Mensageiro/metabolismo , Xenopus/metabolismo
8.
J Physiol Sci ; 69(2): 305-316, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30478741

RESUMO

FK506 (tacrolimus) is an immunosuppressant widely used as an ointment in the treatment of atopic dermatitis. However, local application of FK506 can evoke burning sensations in atopic dermatitis patients, and its mechanisms are unknown. In this study, we found that FK506 activates transient receptor potential ankyrin 1 (TRPA1) channels. In Ca2+-imaging experiments, increases in intracellular Ca2+ concentrations ([Ca2+]i) by FK506 were observed in HEK293T cells expressing hTRPA1 or hTRPM8. FK506-induced currents were observed in HEK293T cells expressing hTRPA1 or mTRPA1, but less or not at all in cells expressing hTRPV1 or hTRPM8 using a patch-clamp technique. FK506 also evoked single-channel opening of hTRPA1 in an inside-out configuration. FK506-induced [Ca2+]i increases were also observed in TRPA1-expressing mouse primary sensory neurons. Furthermore, injection of FK506 evoked licking or biting behaviors and these behaviors were almost abolished in TRPA1 knockout mice. These results indicate that FK506 might cause pain sensations through TRPA1 activation.


Assuntos
Dor/tratamento farmacológico , Sensação/efeitos dos fármacos , Canal de Cátion TRPA1/metabolismo , Tacrolimo/farmacologia , Animais , Cálcio/metabolismo , Canais de Cálcio/metabolismo , Linhagem Celular , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Dor/metabolismo , Células Receptoras Sensoriais/metabolismo
9.
Sci Rep ; 8(1): 15149, 2018 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-30310166

RESUMO

Certain methanogens deteriorate steel surfaces through a process called microbiologically influenced corrosion (MIC). However, the mechanisms of MIC, whereby methanogens oxidize zerovalent iron (Fe0), are largely unknown. In this study, Fe0-corroding Methanococcus maripaludis strain OS7 and its derivative (strain OS7mut1) defective in Fe0-corroding activity were isolated. Genomic analysis of these strains demonstrated that the strain OS7mut1 contained a 12-kb chromosomal deletion. The deleted region, termed "MIC island", encoded the genes for the large and small subunits of a [NiFe] hydrogenase, the TatA/TatC genes necessary for the secretion of the [NiFe] hydrogenase, and a gene for the hydrogenase maturation protease. Thus, the [NiFe] hydrogenase may be secreted outside the cytoplasmic membrane, where the [NiFe] hydrogenase can make direct contact with Fe0, and oxidize it, generating hydrogen gas: Fe0 + 2 H+ → Fe2+ + H2. Comparative analysis of extracellular and intracellular proteomes of strain OS7 supported this hypothesis. The identification of the MIC genes enables the development of molecular tools to monitor epidemiology, and to perform surveillance and risk assessment of MIC-inducing M. maripaludis.


Assuntos
Genoma Bacteriano , Ilhas Genômicas , Hidrogenase/genética , Hidrogenase/metabolismo , Ferro/metabolismo , Mathanococcus/genética , Mathanococcus/metabolismo , Antibacterianos/farmacologia , Sequência de Bases , Corrosão , Ordem dos Genes , Instabilidade Genômica , Mathanococcus/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Modelos Teóricos , Oxirredução
10.
Biomed Rep ; 9(3): 253-258, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30271602

RESUMO

In a previous genome-wide association study, plexin A2 (PLXNA2) was suggested as one of the candidate genes for mandibular prognathism. PLXNA2 encodes plexin A2, a member of the plexin-A family of semaphorin co-receptors. Semaphorin 3A (sema3A) exerts an osteoprotective effect. However, to the best of our knowledge, there have been no previous studies examining the role of sema3A or plexin A2 on human chondrocytes. The objectives of the present study were to examine the function of sema3A and its receptor, plexin A2, in human chondrocytes. Normal human chondrocytes were cultured in media with either a high (100 ng/ml) or a low (1 ng/ml) concentration of sema3A, or without sema3A as a control. Cells and extracellular matrices were assayed for concentrations of protein and parathyroid hormone-related peptide receptor 1 (PTH-R1) using a bicinchoninic acid assay and an enzyme immunoassay, respectively. At culture day 7, the high and low concentrations of exogenous sema3A significantly increased the protein content compared with the control (P=0.0008 and 0.00002, respectively). At culture day 14, a high concentration of exogenous sema3A significantly increased the protein content and decreased the concentration of PTH-R1 compared with the control (P=0.002). The present study revealed novel results that exogenous sema3A suppresses the expression of PTH-R1 in human proliferative chondrocytes and suggested that sema3A may affect human chondrocytes via its receptor, plexin A2.

11.
Biol Pharm Bull ; 41(8): 1135-1144, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30068861

RESUMO

Brown and beige adipocytes are a major site of mammalian non-shivering thermogenesis and energy dissipation. Obesity is caused by an imbalance between energy intake and expenditure and has become a worldwide health problem. Therefore modulation of thermogenesis in brown and beige adipocytes could be an important application for body weight control and obesity prevention. Over the last few decades, the involvement of thermo-sensitive transient receptor potential (TRP) channels (including TRPV1, TRPV2, TRPV3, TRPV4, TRPM4, TRPM8, TRPC5, and TRPA1) in energy metabolism and adipogenesis in adipocytes has been extensively explored. In this review, we summarize the expression, function, and pathological/physiological contributions of these TRP channels and discuss their potential as future therapeutic targets for preventing and combating human obesity and obesity-related metabolic disorders.


Assuntos
Tecido Adiposo Marrom/fisiologia , Canais de Potencial de Receptor Transitório/fisiologia , Tecido Adiposo Marrom/metabolismo , Animais , Metabolismo Energético , Humanos , Temperatura , Termogênese , Canais de Potencial de Receptor Transitório/metabolismo
12.
J Dermatol Sci ; 90(3): 332-342, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29610016

RESUMO

BACKGROUND: Keratinocytes release several factors that are involved in wound contracture and scar formation. We previously reported that a three-dimensional reconstruction model derived from rat skin represents a good wound healing model. OBJECTIVE: We characterized the role of transient receptor potential (TRP) channels in the release of transforming growth factor (TGF)-ß1 from keratinocytes and the differentiation of fibroblasts to identify possible promising pharmacological approaches to prevent scar formation and contractures. METHODS: The three-dimensional culture model was made from rat keratinocytes seeded on a collagen gel in which dermal fibroblasts had been embedded. RESULTS: Among the TRP channel inhibitors tested, the TRPV2 inhibitors SKF96365 and tranilast attenuated most potently keratinocyte-dependent and - independent collagen gel contraction due to TGF-ß signaling as well as TGF-ß1 release from keratinocytes and α-smooth muscle actin production in myofibroblasts. Besides the low amounts detected in normal dermis, TRPV2 mRNA and protein levels were increased after fibroblasts were embedded in the gel. TRPV2 was also expressed in the epidermis and keratinocyte layers of the model. Both inhibitors and TRPV2 siRNA attenuated the intracellular increase of Ca2+ induced by the TRPV agonist 2-aminoethoxydiphenyl borate in TGF-ß1-pretreated fibroblasts. CONCLUSION: This is the first study to show that compounds targeting TRPV2 channels ameliorate wound contraction through the inhibition of TGF-ß1 release and the differentiation of dermal fibroblasts in a culture model.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Miofibroblastos/fisiologia , Canais de Cátion TRPV/antagonistas & inibidores , Fator de Crescimento Transformador beta1/metabolismo , Cicatrização/efeitos dos fármacos , Actinas/metabolismo , Animais , Compostos de Boro/farmacologia , Células Cultivadas , Células Epidérmicas , Epiderme/efeitos dos fármacos , Epiderme/fisiologia , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Miofibroblastos/efeitos dos fármacos , Cultura Primária de Células , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Wistar , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/metabolismo
13.
Biochem Biophys Res Commun ; 496(2): 381-386, 2018 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-29326042

RESUMO

Epithelial-mesenchymal transition (EMT) is a biological event in which epithelial cells lose their polarity and cell-cell adhesions and concomitantly acquire mesenchymal traits, and is thought to play an important role in pathological processes such as wound healing and cancer progression. In this study, we evaluated transforming growth factor (TGF)-ß1-treated human keratinocyte HaCaT cells as an in vitro model of EMT. HaCaT cells were changed into an elongated fibroblast-like morphology, which is indicative of EMT in response to TGF-ß1. Phalloidin staining demonstrated the formation of actin stress fibers in TGF-ß1-treated cells. Quantitative RT-PCR analysis revealed that TGF-ß1 increased the mRNA levels of EMT transcription factors (SNAI2, TWIST1, and ZEB1) and mesenchymal markers (CDH2, VIM, and FN1), while it decreased the transcripts of epithelial phenotypic genes (CLDN1, OCLN, KRT5, KRT15, KRT13, and TGM1). Furthermore, we found that KRT13 was drastically suppressed through the reduction of RNA polymerase II occupancy of its promoter, which was accompanied by a decrease in active histone marks (H3K4me3 and H3K27ac) and an increase in a repressive mark (H3K27me3) during EMT. These findings indicate that the TGF-ß1-induced EMT program regulates a subset of epithelial and mesenchymal marker genes, and that KRT13 is transcriptionally suppressed through the modulation of the chromatin state at the KRT13 promoter in HaCaT cells.


Assuntos
Epigênese Genética , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Queratina-13/genética , Queratinócitos/efeitos dos fármacos , Fator de Crescimento Transformador beta1/farmacologia , Actinas/genética , Actinas/metabolismo , Antígenos CD/genética , Antígenos CD/metabolismo , Caderinas/genética , Caderinas/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Transformada , Citocinas/genética , Citocinas/metabolismo , Transição Epitelial-Mesenquimal/genética , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibronectinas , Histonas/genética , Histonas/metabolismo , Humanos , Queratina-13/metabolismo , Queratinócitos/citologia , Queratinócitos/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Regiões Promotoras Genéticas , RNA Polimerase II/genética , RNA Polimerase II/metabolismo , Transdução de Sinais , Fatores de Transcrição da Família Snail/genética , Fatores de Transcrição da Família Snail/metabolismo , Proteína 1 Relacionada a Twist/genética , Proteína 1 Relacionada a Twist/metabolismo , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo
14.
FASEB J ; 31(11): 5036-5048, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28754711

RESUMO

Gut microbiota can regulate the host energy metabolism; however, the underlying mechanisms that could involve gut microbiota-derived compounds remain to be understood. Therefore, in this study, we investigated the effects of KetoA [10-oxo-12(Z)-octadecenoic acid]-a linoleic acid metabolite produced by gut lactic acid bacteria-on whole-body energy metabolism and found that dietary intake of KetoA could enhance energy expenditure in mice, thereby protecting mice from diet-induced obesity. By using Ca2+ imaging and whole-cell patch-clamp methods, KetoA was noted to potently activate transient receptor potential vanilloid 1 (TRPV1) and enhance noradrenalin turnover in adipose tissues. In addition, KetoA up-regulated genes that are related to brown adipocyte functions, including uncoupling protein 1 (UCP1) in white adipose tissue (WAT), which was later diminished in the presence of a ß-adrenoreceptor blocker. By using obese and diabetic model KK-Ay mice, we further show that KetoA intake ameliorated obesity-associated metabolic disorders. In the absence of any observed KetoA-induced antiobesity effect or UCP1 up-regulation in TRPV1-deficient mice, we prove that the antiobesity effect of KetoA was caused by TRPV1 activation-mediated browning in WAT. KetoA produced in the gut could therefore be involved in the regulation of host energy metabolism.-Kim, M., Furuzono, T., Yamakuni, K., Li, Y., Kim, Y.-I., Takahashi, H., Ohue-Kitano, R., Jheng, H.-F., Takahashi, N., Kano, Y., Yu, R., Kishino, S., Ogawa, J., Uchida, K., Yamazaki, J., Tominaga, M., Kawada, T., Goto, T. 10-oxo-12(Z)-octadecenoic acid, a linoleic acid metabolite produced by gut lactic acid bacteria, enhances energy metabolism by activation of TRPV1.


Assuntos
Bactérias/metabolismo , Metabolismo Energético , Microbioma Gastrointestinal , Ácido Linoleico/metabolismo , Ácidos Oleicos/metabolismo , Canais de Cátion TRPV/metabolismo , Adipócitos Marrons/metabolismo , Tecido Adiposo Branco/metabolismo , Animais , Masculino , Camundongos , Camundongos Knockout , Proteína Desacopladora 1/metabolismo , Regulação para Cima
15.
J Physiol Sci ; 67(5): 549-560, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28656459

RESUMO

To date, 11 thermosensitive transient receptor potential (thermo-TRP) channels have been identified. Recent studies have characterized the mechanism of thermosensing by thermo-TRPs and the physiological role of thermo-TRPs in energy metabolism. In this review, we highlight the role of various thermo-TRPs in energy metabolism and hormone secretion. In the pancreas, TRPM2 and other TRPs regulate insulin secretion. TRPV2 expressed in brown adipocytes contributes to differentiation and/or thermogenesis. Sensory nerves that express TRPV1 promote increased energy expenditure by activating sympathetic nerves and adrenaline secretion. Here, we first show that capsaicin-induced adrenaline secretion is completely impaired in TRPV1 knockout mice. The thermogenic effects of TRPV1 agonists are attributable to brown adipose tissue (BAT) activation in mice and humans. Moreover, TRPA1- and TRPM8-expressing sensory nerves also contribute to potentiation of BAT thermogenesis and energy expenditure in mice. Together, thermo-TRPs are promising targets for combating obesity and metabolic disorders.


Assuntos
Metabolismo Energético/fisiologia , Sensação Térmica/fisiologia , Canais de Potencial de Receptor Transitório/metabolismo , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Marrom/fisiologia , Animais , Humanos , Termogênese/fisiologia
16.
J Plant Res ; 129(6): 1013-1020, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27542159

RESUMO

The evolution of mycoheterotrophy has been accompanied by extreme reductions in plant leaf size and photosynthetic capacity. Partially mycoheterotrophic plants, which obtain carbon from both photosynthesis and their mycorrhizal fungi, include species with leaves of normal size and others that are tiny-leaved. Thus, plant species may lose their leaves in a gradual process of size reduction rather than through a single step mutation. Little is known about how the degree of mycoheterotrophy changes during reductions in leaf size. We compared the degree of mycoheterotrophy among five Japanese Cephalanthera species, four with leaves of normal size (Cephalanthera falcata, Cephalanthera erecta, Cephalanthera longibracteata and Cephalanthera longifolia), one with tiny leaves (Cephalanthera subaphylla), and one albino form of C. falcata (as reference specimens for fully mycoheterotrophic plants). The levels of mycoheterotrophy were determined by stable isotope natural abundance analysis. All Cephalanthera species were relatively enriched in 13C and 15N in comparison with surrounding autotrophic plants. Cephalanthera subaphylla was strongly enriched in 13C and 15N to levels similar to the albinos. Species with leaves of normal size were significantly less enriched in 13C than C. subaphylla and the albinos. Thus, C. subaphylla was strongly mycoheterotrophic, obtaining most of its carbon from mycorrhizal fungi even though it has tiny leaves; species with leaves of normal size were partially mycoheterotrophic. Hence, during the evolutionary pathway to full mycoheterotrophy, some plant species appear to have gained strong mycoheterotrophic abilities before completely losing foliage leaves.


Assuntos
Carbono/metabolismo , Fungos/metabolismo , Processos Heterotróficos , Nitrogênio/metabolismo , Orchidaceae/metabolismo , Orchidaceae/microbiologia , Japão , Orchidaceae/anatomia & histologia , Folhas de Planta/anatomia & histologia , Especificidade da Espécie , Simbiose
17.
Yakugaku Zasshi ; 136(3): 485-90, 2016.
Artigo em Japonês | MEDLINE | ID: mdl-26935091

RESUMO

Cl(-)-permeable channels and transporters expressed on the cell membranes of various mammalian cell types play pivotal roles in the transport of electrolytes and water, pH regulation, cell volume and membrane excitability, and are therefore expected to be useful molecular targets for drug discovery. Both TMEM16A (a possible candidate for Ca(2+)-regulated Cl(-) channels recently identified) and cystic fibrosis transmembrane conductance regulator (CFTR) (or cAMP-regulated Cl(-) channels) have been known to be involved in Cl(-) secretion and reabsorption in the rat salivary gland. Crosstalk between two types of regulatory pathways through these two types of channels has also been described. Previously, we demonstrated that CLCA, a Ca(2+)-activated Cl(-) channel modulator, was involved in Cl(-) absorption in rat salivary ducts. In addition to Ca(2+), basal NF-κB activity in a mouse keratinocyte line was shown to be involved in the transcriptional regulation of CLCA. Conversely, a truncated isoform of CLCA was found in undifferentiated epithelial cells present in the rat epidermal basal layers. Under regulation by Ca(2+) and PKC, the surface expression of ß1-integrin and cell adhesion were decreased in the CLCA-overexpressing cells. Knockdown of this isoform elevated the expression of ß1-integrin in rat epidermis in vivo. These results indicate that the specific differentiation-dependent localization of CLCA, and transcriptional regulation through Ca(2+), are likely to affect ion permeability and the adhesive potential of epithelial cells. In summary, these types of Cl(-) channels and their modulators may function in a coordinated manner in regulating the functions of epithelial cells under different physiological conditions.


Assuntos
Diferenciação Celular/genética , Canais de Cloreto/fisiologia , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Ferro/metabolismo , Animais , Anoctamina-1 , Cálcio/fisiologia , Canais de Cloreto/genética , Canais de Cloreto/metabolismo , Cloretos/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/fisiologia , Humanos , Camundongos , NF-kappa B/fisiologia , Proteínas de Neoplasias/fisiologia , Proteínas Associadas à Matriz Nuclear/fisiologia , Ratos , Glândulas Salivares/metabolismo , Transcrição Gênica
18.
Clin Implant Dent Relat Res ; 18(5): 883-894, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26179832

RESUMO

BACKGROUND: Modification of the surface topography of biomaterials is a critical factor for the proliferation and differentiation of osteoblasts. Elucidating the biological response to surface roughening is necessary for clinical application of zirconia implants. PURPOSE: To investigate the effects of fiber laser-induced zirconia surface roughening on cultured osteoblast-like cell morphology, proliferation, differentiation, and calcification, and on in vivo bone formation. MATERIALS AND METHODS: Sixty-six machine-surfaced yttria-tetragonal zirconia polycrystal plates (S-Zr) and 16 machine-surfaced implants were used as controls. We prepared 66 rough plates (R-Zr) and 16 rough implants by surface treatment using a fiber laser. RESULTS: MC3T3-E1 cells spread well in all directions on S-Zr, whereas elongated cells with poorly organized actin stress fibers were observed on R-Zr. Cell proliferation was significantly greater on R-Zr than on S-Zr. The Runx2 mRNA level increased time dependently in osteogenic culture condition. Alkaline phosphatase activity and osteocalcin mRNA levels were higher on R-Zr compared with S-Zr. Alizarin red S staining revealed greater calcification on R-Zr than on S-Zr. Laser treatment of zirconia implant bodies placed in rat tibiae increased the bone-implant contact ratio and removal torque considerably. CONCLUSIONS: Our results suggest that fiber laser irradiation produces adequate surface roughening of zirconia ceramics to support osseointegration.


Assuntos
Lasers , Osteogênese/fisiologia , Zircônio , Animais , Técnicas In Vitro , Masculino , Ratos , Ratos Sprague-Dawley , Propriedades de Superfície
19.
Tissue Eng Regen Med ; 13(5): 527-537, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30603433

RESUMO

Three-dimensional (3D) cultures are known to promote cell differentiation. Previously, we investigated the differentiation of rat dermal fibroblasts to α-smooth muscle actin (α-SMA)-positive myofibroblasts through transforming growth factor (TGF)-ß production using a 3D culture model. Here, we investigated the phenotypic change from dermal mesenchymal cells (mostly fibroblasts) to osteoblast-like cells, being inspired by the roles of smooth muscle cells or fibroblasts during vascular calcification. Spindle-shaped cells that grew in heterologous populations out of dermal explants from 2-day-old Wistar rats were cultured within a collagen matrix. α-SMA and alkaline phosphatase (ALP) meßsenger RNA (mRNA) levels initially increased, followed by a rise in Runx2 and osteocalcin (OCN) mRNA levels without calcification. Calcium deposits were produced in the presence of a high concentration of inorganic phosphate (2.1 mM) or ß-glycerophosphate (ßGP, 10 mM) after 2 weeks of culture, and both were sensitive to an inhibitor of type III phosphate transporters. An ALP inhibitor decreased only ßGP-induced calcification. Inhibition of TGF-ß type-I receptors attenuated ALP mRNA levels and ßGP-induced calcification, suggesting that endogenous TGF-ß stimulates ALP activity and then ßGP breakdown. An increase in the number of cells embedded in the collagen gel enhanced the mRNA levels of Runx2 and OCN, but not of ALP. Collectively, several factors are likely to promote the differentiation of dermal mesenchymal cells into osteoblast-like cells and ectopic calcification in a 3D collagen matrix, implying the utility of these cells as a potential autologous cell source for tissue engineering.

20.
CEN Case Rep ; 5(2): 197-202, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28508976

RESUMO

Focal segmental glomerulosclerosis (FSGS) is classified into five variants, with the collapsing variant being the most rare. Collapsing FSGS is characterized by a black racial predominance and is often associated with human immunodeficiency virus-associated nephropathy. However, the number of idiopathic cases is increasing and the presentation of non-black patients becoming more routine. Our analysis of 15 previous reports investigating FSGS variants shows that the collapsing variant accounts for 10.6 % of FSGS cases and its average age of onset is 32 years old. The current case is one of the oldest cases of idiopathic collapsing FSGS identified, being an 81-year-old Japanese woman. She presented with severe renal insufficiency (serum creatinine 7.9 mg/dL, albumin 1.5 g/dL) and so underwent hemodialysis immediately. Urinalysis demonstrated 3+ proteinuria and 3+ hematuria and the serological work up was all negative. Renal biopsy showed wrinkling of capillary walls with collapse lumens in every glomerulus, without endothelial tubuloreticular inclusions. Combined treatment with steroids, cyclosporine and low-density lipoprotein apheresis increased urine output slightly but she was unable to withdraw from hemodialysis and died 3 months later. This variant is reported to have the highest rate of progression to end-stage renal disease, regardless of the therapeutic intervention. However, there are also examples of cases with partial or complete remission in the literature. Progressive cases, like the current case, seem to be difficult to induce remission in, so it is important to diagnose idiopathic collapsing FSGS at an early stage by performing a renal biopsy, even in elderly patients.

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