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1.
Artigo em Inglês | MEDLINE | ID: mdl-38627197

RESUMO

Twelve years after the first edition of The Guideline for Gynecological Practice, which was jointly edited by The Japan Society of Obstetrics and Gynecology and The Japan Association of Obstetricians and Gynecologists, the 5th Revised Edition was published in 2023. The 2023 Guidelines includes 5 additional clinical questions (CQs), which brings the total to 103 CQ (12 on infectious disease, 30 on oncology and benign tumors, 29 on endocrinology and infertility and 32 on healthcare for women). Currently, a consensus has been reached on the Guidelines, and therefore, the objective of this report is to present the general policies regarding diagnostic and treatment methods used in standard gynecological outpatient care that are considered appropriate. At the end of each answer, the corresponding Recommendation Level (A, B, C) is indicated.

2.
Biochem Biophys Res Commun ; 685: 149170, 2023 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-37924777

RESUMO

Our previous study revealed that changes of the intracellular Cl- concentration ([Cl-]i) affected cell proliferation in cancer cells. However, the role of Cl- on cell migration and invasion in cancer cells remains unanalyzed. Therefore, the aim of the present study is to investigate whether changes of [Cl-]i affects cell migration and invasion of cancer cells. In human prostate cancer DU145 cells, cell migration and invasion were enhanced by culturing in the low Cl- medium (replacement of Cl- by NO3-). We also found that DU145 cells in the low Cl- condition caused significant transient ERK1/2 activation followed by an increase of MMP-1 mRNA levels. Inhibition of ERK1/2 activation in the low Cl- condition reduced enhancement of MMP-1 mRNA levels and decreased cell migration and invasion. These observations indicate that [Cl-]i plays important roles in metastatic function by regulating the ERK1/2 signaling pathway in human prostate cancer cells, and intracellular Cl- would be one of the key targets for anti-cancer therapy.


Assuntos
Carcinoma , Neoplasias da Próstata , Masculino , Humanos , Sistema de Sinalização das MAP Quinases , Cloretos/metabolismo , Metaloproteinase 1 da Matriz/genética , Próstata/metabolismo , Linhagem Celular Tumoral , Transdução de Sinais , Neoplasias da Próstata/patologia , Movimento Celular/fisiologia , RNA Mensageiro/metabolismo , Carcinoma/genética , Invasividade Neoplásica/genética , Regulação Neoplásica da Expressão Gênica
3.
J Obstet Gynaecol Res ; 47(1): 5-25, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33145837

RESUMO

Nine years after the first edition of The Guideline for Gynecological Practice, which was jointly edited by The Japan Society of Obstetrics and Gynecology and The Japan Association of Obstetricians and Gynecologists, the 4th Revised Edition was published in 2020. The 2020 Guidelines includes 4 additional clinical questions (CQ), which brings the total to 99 CQ (12 on infectious disease, 29 on oncology and benign tumors, 29 on endocrinology and infertility and 29 on healthcare for women). Currently, a consensus has been reached on the Guidelines, and therefore, the objective of this report is to present the general policies regarding diagnostic and treatment methods used in standard gynecological outpatient care that are considered appropriate. At the end of each answer, the corresponding Recommendation Level (A, B, C) is indicated.


Assuntos
Ginecologia , Obstetrícia , Médicos , Feminino , Humanos , Japão , Gravidez , Sociedades Médicas
4.
Cell Physiol Biochem ; 42(1): 68-80, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28554181

RESUMO

BACKGROUND/AIMS: Our previous study revealed that cytosolic Cl- affected neurite elongation promoted via assembly of microtubule in rat pheochromocytoma PC12D cells and Cl--induced blockade of intrinsic GTPase enhanced tubulin polymerization in vitro. Paclitaxel (PTX) is a microtubule-targeted chemotherapeutic drug and stabilizes microtubules resulting in mainly blockade of mitosis at the metaphase-anaphase transition and induction of apoptosis. In the present study, we tried to clarify whether the cytosolic Cl- affected PTX ability to inhibit cell growth in the gastric cancer cell line, MKN28. METHODS: To clarify the cytosolic Cl- action on PTX-induced cell death and metaphase-anaphase transition in the gastric cancer cell line, MKN28 cell, and PTX-induced tubulin polymerization, we performed cell proliferation assay, cytosolic Cl- concentration measurement, immunofluorescence microscopy, and in vitro tubulin polymerization assay. RESULTS: The decline of cytosolic Cl- weakened the cytotoxic effect of PTX on cell proliferation of MKN28 cells, which could pass through the metaphase-anaphase transition. Moreover, in vitro PTX-induced tubulin polymerization was diminished under the low Cl- condition. CONCLUSIONS: Our results strongly suggest that the upregulation of cytosolic Cl- concentration would enhance the antitumor effect of PTX, and that the cytosolic Cl- would be one of the key targets for anti-cancer therapy.


Assuntos
Apoptose/efeitos dos fármacos , Cloretos/metabolismo , Paclitaxel/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citosol/metabolismo , Humanos , Microscopia de Fluorescência , Neoplasias Gástricas/fisiopatologia , Tubulina (Proteína)/química , Tubulina (Proteína)/metabolismo , Moduladores de Tubulina/farmacologia
6.
J Infect Chemother ; 22(3): 180-3, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26719132

RESUMO

Rapidly growing non-tuberculous mycobacteria (RGM) are usually detected in blood cultures after 4-5 days of incubation, so it is important to differentiate RGM from contamination of commensal organisms on human skin. We report an unusual case of Mycobacterium mageritense bacteremia and infection of an implantable cardioverter defibrillator originally misidentified as Corynebacterium spp. or Nocardia spp. in gram-stained smears. 16S rRNA gene sequencing had utility in the definitive identification of isolates. We should be aware that RGM infection may exist in repeated implantable device infections.


Assuntos
Desfibriladores Implantáveis/efeitos adversos , Infecções por Mycobacterium não Tuberculosas , Micobactérias não Tuberculosas/genética , Infecções Relacionadas à Prótese , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
J Neurosci ; 34(3): 764-75, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24431435

RESUMO

CLC-2 is a hyperpolarization-activated, inwardly rectifying chloride channel. Although the properties of the CLC-2 channel have been well characterized, its function in vivo is not well understood. We have found that channels encoded by the Caenorhabditis elegans CLC-2 homolog clh-3 regulate the activity of the spontaneously active hermaphrodite-specific neurons (HSNs), which control the egg-laying behavior. We identified a gain-of-function mutation in clh-3 that increases channel activity. This mutation inhibits egg laying and inhibits HSN activity by decreasing its excitability. Conversely, loss-of-function mutations in clh-3 lead to misregulated egg laying and an increase in HSN excitability, indicating that these channels modulate egg laying by limiting HSN excitability. clh-3-encoded channels are not required for GABAA-receptor-mediated inhibition of the HSN. However, they require low intracellular chloride for HSN inhibition, indicating that they inhibit excitability directly by mediating chloride influx. This mechanism of CLH-3-dependent modulation may be conserved in other neurons in which the driving force favors chloride influx.


Assuntos
Proteínas de Caenorhabditis elegans/fisiologia , Canais de Cloreto/fisiologia , Potenciais Pós-Sinápticos Excitadores/fisiologia , Neurônios Motores/fisiologia , Oviposição/fisiologia , Animais , Canais de Cloro CLC-2 , Caenorhabditis elegans , Células HEK293 , Humanos
8.
Biochem Biophys Res Commun ; 445(1): 170-4, 2014 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-24502946

RESUMO

Insulin resistance in the skeletal muscle is manifested by diminished insulin-stimulated glucose uptake and is a core factor in the pathogenesis of type 2 diabetes mellitus (DM), but the mechanism causing insulin resistance is still unknown. Our recent study has shown that pH of interstitial fluids was lowered in early developmental stage of insulin resistance in OLETF rats, a model of type 2 DM. Therefore, in the present study, we confirmed effects of the extracellular pH on the insulin signaling pathway in a rat skeletal muscle-derived cell line, L6 cell. The phosphorylation level (activation) of the insulin receptor was significantly diminished in low pH media. The phosphorylation level of Akt, which is a downstream target of the insulin signaling pathway, also decreased in low pH media. Moreover, the insulin binding to its receptor was reduced by lowering extracellular pH, while the expression of insulin receptors on the plasma membrane was not affected by the extracellular pH. Finally, insulin-stimulated 2-deoxyglucose uptake in L6 cells was diminished in low pH media. Our present study suggests that lowered extracellular pH conditions may produce the pathogenesis of insulin resistance in skeletal muscle cells.


Assuntos
Espaço Extracelular/química , Resistência à Insulina , Insulina/farmacologia , Músculo Esquelético/efeitos dos fármacos , Receptor de Insulina/metabolismo , Animais , Western Blotting , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Desoxiglucose/farmacocinética , Concentração de Íons de Hidrogênio , Hipoglicemiantes/metabolismo , Hipoglicemiantes/farmacologia , Insulina/metabolismo , Fibras Musculares Esqueléticas/citologia , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/citologia , Músculo Esquelético/metabolismo , Mioblastos/citologia , Mioblastos/efeitos dos fármacos , Mioblastos/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos
9.
Nihon Rinsho ; 72(10): 1806-12, 2014 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-25509807

RESUMO

Elderly fracture is a critical public health issue for older adults, and falls risk assessment is an expected competency for medical worker. The prevention from fall fracture is one of the important items of medical safety, and although fall assessment is carried out, it is not much effective. One of the reasons is that there is not the simple and easy tool of the fall prediction. The aim of this study was to design an innovative method of falls risk assessment using standing ability of the elderly. We devised new fall assessment score (Mimamori score) that scored lifting assistance movement. We incorporate it in real duties after 2011, inflect for the fall prevention.


Assuntos
Acidentes por Quedas , Fraturas Ósseas/etiologia , Idoso , Idoso de 80 Anos ou mais , Previsões , Humanos , Medição de Risco
10.
Biochem Biophys Res Commun ; 432(4): 650-3, 2013 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-23416075

RESUMO

Propolis, a resinous mixture collected from plants by the Apis mellifera bee, contains high level nutrient factors including vitamins, polyphenols, and amino acids that would be expected to improve insulin sensitivity. Insulin resistance would secondarily cause elevation of blood pressure and increase the risk of cardiovascular diseases. The purpose of this study is to investigate the effect of propolis extracts on blood glucose levels and blood pressures in an early developmental stage of insulin resistance in Otsuka Long-Evans Tokushima Fatty (OLETF) rats. OLETF rats (10 weeks old) were divided into three different groups: normal diet, 0.1% propolis diet, and 0.5% propolis diet. After 8 weeks, blood glucose levels, blood pressures, plasma metabolic factors and hormones, and interstitial fluid pH were measured. Casual blood glucose levels were decreased associated with a reduction of plasma insulin levels in both propolis diet groups compared with normal diet group. Propolis decreased systolic blood pressure with no significant changes in plasma aldosterone levels. We also found that interstitial fluid pH in ascites, liver, and skeletal muscle was higher in rats fed propolis diet than rats fed normal diet. These data suggests that dietary propolis improves insulin sensitivity and blood pressures in the early stage of the process in development of insulin resistance, which may be mediated by suppression of metabolic acidosis.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Suplementos Nutricionais , Líquido Extracelular/efeitos dos fármacos , Resistência à Insulina , Própole/administração & dosagem , Tecido Adiposo/efeitos dos fármacos , Aldosterona/sangue , Animais , Glicemia/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Líquido Extracelular/química , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Insulina/sangue , Ratos , Ratos Endogâmicos OLETF , Urina/química
11.
Arch Biochem Biophys ; 539(1): 92-8, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23831333

RESUMO

K(+)-Cl(-) cotransporter (KCC) has been shown to be involved in cell proliferation as well as cell volume regulation. A regulatory role of KCC in cell cycle progression of breast cancer MDA-MB-231 cells was explored by using synchronized MDA-MB-231 cells and dihydro-indenyloxy-alkanoic acid (DIOA), a potent inhibitor of KCC. MDA-MB-231 cells cultured in the presence of DIOA exhibited an increase in cell volume, a decrease in intracellular Cl(-) concentration, and reduction in cell proliferation with the G0/G1 phase arrest, which was accompanied with down-regulation of cyclin D1 and cyclin E2, and up-regulation of p21. Among these molecules, the expression of cyclin E2, a molecule essential for the transition from G1 to S phase, was markedly suppressed by DIOA treatment. DIOA-mediated up- or down-regulation of these molecules occurred at the transcriptional level. These findings suggest that KCC plays an important role in the early phase of cell cycle progression by regulating the expression of cyclin D1, cyclin E2, and p21, the molecules essential for the cell cycle progression.


Assuntos
Neoplasias da Mama/patologia , Ciclo Celular , Simportadores/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Ciclina D1/genética , Ciclina D1/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Ciclinas/genética , Ciclinas/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Cotransportadores de K e Cl-
12.
J Patient Saf ; 19(8): 564-572, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37843989

RESUMO

OBJECTIVES: Disruptive clinician behavior worsens communication, information transfer, and teamwork, all of which negatively affect patient safety. Improving safety in medical care requires an accurate assessment of the damage caused by disruptive clinician behavior. Psychometric scales complement case reports, but existing scales have significant limitations. Therefore, this study developed a psychometric scale based on the psychological paradigm to assess disruptive clinician behavior. METHODS: The scale was developed through a sequence of steps. First, we used an open-ended questionnaire targeting 712 nurses, content analysis, and content validity assessment by 5 experts to determine valid items for disruptive clinical behavior. Next, an Internet questionnaire survey targeting 1000 health care staff, exploratory factor analysis, and subfactor analysis was conducted to identify necessary and sufficient factors. Then, we calculated difficulty level and discriminative power. We also conducted a field questionnaire survey targeting 84 staff in a hospital. Finally, we calculated ω coefficients and then used confirmatory factor analysis to verify the fit of the hypothesized model. RESULTS: Our open-ended survey involving 478 nurses identified 47 codes in 9 categories. The questionnaire survey involving hospital 1000 medical staff identified 6 factors, with 1 factor subdivided into 4 subfactors and 1 into 2 subfactors. The goodness of fit of the hypothesized 10-factor models with factor pairs and groups was confirmed. CONCLUSIONS: We developed a psychometric scale measuring subjective assessments of harm covering various disruptive clinician behaviors. The scale complements interviews and case reports by generating valid, reliable scores for various disruptive clinician behaviors in health care institutions.


Assuntos
Comportamento Problema , Humanos , Inquéritos e Questionários , Assistência ao Paciente , Corpo Clínico Hospitalar/psicologia , Psicometria , Reprodutibilidade dos Testes
13.
Biomed Res ; 44(1): 17-29, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36682797

RESUMO

The present study tried to clarify if mumefural would prevent hyperglycemia, one of the typical symptoms of type 2 diabetes mellitus (T2DM), since mumefural is an extract from Japanese apricots preventing hyperglycemia. To clarify if mumefural would prevent T2DM pathogenesis, we used Otsuka Long-Evans Tokushima fatty (OLETF) rats, T2DM model. Mumefural diminished hyperglycemia, HOMA-IR and plasma triglyceride concentration in OLETF rats under fasting conditions. In addition, mumefural elevated protein expression of sodium-coupled monocarboxylate transporter 1 (SMCT1) in the distal colon participating in absorption of weak organic acids, which behave as bases but not acids after absorption into the body. Mumefural also increased the interstitial fluid pH around the brain hippocampus lowered in OLETF rats compared with non-T2DM LETO rats used as control for OLETF rats. Amyloid-beta accumulation in the brain decreased in accordance with the pH elevation. On the one hand, mumefural didn't affect plasma concentrations of glucagon, GLP-1, GIP or PYY under fasting conditions. Taken together, these observations indicate that: 1) mumefural would be a useful functional food improving hyperglycemia, insulin resistance and the lowered interstitial fluid pH in T2DM; 2) the interstitial fluid pH would be one of key factors influencing the accumulation of amyloid-beta.


Assuntos
Diabetes Mellitus Tipo 2 , Hiperglicemia , Resistência à Insulina , Ratos , Animais , Ratos Endogâmicos OLETF , Glicemia/metabolismo , Insulina , Líquido Extracelular/metabolismo , Encéfalo/metabolismo , Concentração de Íons de Hidrogênio
14.
Phys Med Biol ; 68(17)2023 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-37506710

RESUMO

Objective. Photon counting CT (PCCT) has been a research focus in the last two decades. Recent studies and advancements have demonstrated that systems using semiconductor-based photon counting detectors (PCDs) have the potential to provide better contrast, noise and spatial resolution performance compared to conventional scintillator-based systems. With multi-energy threshold detection, PCD can simultaneously provide the photon energy measurement and enable material decomposition for spectral imaging. In this work, we report a performance evaluation of our first CdZnTe-based prototype full-size PCCT system through various phantom imaging studies.Approach.This prototype system supports a 500 mm scan field-of-view and 10 mmz-coverage at isocenter. Phantom scans were acquired using 120 kVp from 50 to 400 mAs to assess the imaging performance on: CT number accuracy, uniformity, noise, spatial resolution, material differentiation and quantification.Main results.Both qualitative and quantitative evaluations show that PCCT, under the tested conditions, has superior imaging performance with lower noise and improved spatial resolution compared to conventional energy integrating detector (EID)-CT. Using projection domain material decomposition approach with multiple energy bin measurements, PCCT virtual monoenergetic images have lower noise, and good accuracy in quantifying iodine and calcium concentrations. These results lead to increased contrast-to-noise ratio (CNR) for both high and low contrast study objects compared to EID-CT at matched dose and spatial resolution. PCCT can also generate super-high resolution images using much smaller detector pixel size than EID-CT and greatly improve image spatial resolution.Significance.Improved spatial resolution and quantification accuracy with reduced image noise of the PCCT images can potentially lead to better diagnosis at reduced radiation dose compared to conventional EID-CT. Increased CNR achieved by PCCT suggests potential reduction in iodine contrast media load, resulting in better patient safety and reduced cost.


Assuntos
Iodo , Tomografia Computadorizada por Raios X , Humanos , Tomografia Computadorizada por Raios X/métodos , Imagens de Fantasmas , Fótons
15.
Biophys J ; 103(8): 1706-18, 2012 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-23083714

RESUMO

The signaling mechanisms that regulate CLC anion channels are poorly understood. Caenorhabditis elegans CLH-3b is a member of the CLC-1/2/Ka/Kb channel subfamily. CLH-3b is activated by meiotic cell-cycle progression and cell swelling. Inhibition is brought about by GCK-3 kinase-mediated phosphorylation of S742 and S747 located on a ∼176 amino acid disordered domain linking CBS1 and CBS2. Much of the inter-CBS linker is dispensable for channel regulation. However, deletion of a 14 amino acid activation domain encompassing S742 and S747 inhibits channel activity to the same extent as GCK-3. The crystal structure of CmCLC demonstrated that CBS2 interfaces extensively with an intracellular loop connecting membrane helices H and I, the C-terminus of helix D, and a short linker connecting helix R to CBS1. Point mutagenesis of this interface identified two highly conserved aromatic amino acid residues located in the H-I loop and the first α-helix (α1) of CBS2. Mutation of either residue to alanine rendered CLH-3b insensitive to GCK-3 inhibition. We suggest that the dephosphorylated activation domain normally interacts with CBS1 and/or CBS2, and that conformational information associated with this interaction is transduced through a conserved signal transduction module comprising the H-I loop and CBS2 α1.


Assuntos
Proteínas de Caenorhabditis elegans/química , Canais de Cloreto/química , Transdução de Sinais , Sequência de Aminoácidos , Animais , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/fisiologia , Domínio Catalítico , Canais de Cloreto/genética , Canais de Cloreto/metabolismo , Canais de Cloreto/fisiologia , Cistationina beta-Sintase/química , Cistationina beta-Sintase/metabolismo , Células HEK293 , Humanos , Potenciais da Membrana , Dados de Sequência Molecular , Mutação , Fosforilação , Domínios e Motivos de Interação entre Proteínas , Proteínas Serina-Treonina Quinases/metabolismo
16.
Am J Physiol Cell Physiol ; 302(12): C1702-12, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22357738

RESUMO

Shrinkage-induced inhibition of the Caenorhabditis elegans cell volume and cell cycle-dependent CLC anion channel CLH-3b occurs by concomitant phosphorylation of S742 and S747, which are located on a 175 amino acid linker domain between cystathionine-ß-synthase 1 (CBS1) and CBS2. Phosphorylation is mediated by the SPAK kinase homolog GCK-3 and is mimicked by substituting serine residues with glutamate. Type 1 serine/threonine protein phosphatases mediate swelling-induced channel dephosphorylation. S742E/S747E double mutant channels are constitutively inactive and cannot be activated by cell swelling. S742E and S747E mutant channels were fully active in the absence of GCK-3 and were inactive when coexpressed with the kinase. Both channels responded to cell volume changes. However, the S747E mutant channel activated and inactivated in response to cell swelling and shrinkage, respectively, much more slowly than either wild-type or S742E mutant channels. Slower activation and inactivation of S747E was not due to altered rates of dephosphorylation or dephosphorylation-dependent conformational changes. GCK-3 binds to the 175 amino acid inter-CBS linker domain. Coexpression of wild-type CLH-3b and GCK-3 with either wild-type or S742E linkers gave rise to similar channel activity and regulation. In contrast, coexpression with the S747E linker greatly enhanced basal channel activity and increased the rate of shrinkage-induced channel inactivation. Our findings suggest the intriguing possibility that the phosphorylation state of S742 in S747E mutant channels modulates GCK-3/channel interaction and hence channel phosphorylation. These results provide a foundation for further detailed studies of the role of multisite phosphorylation in regulating CLH-3b and GCK-3 activity.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Canais de Cloreto/metabolismo , Ativação do Canal Iônico , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas de Caenorhabditis elegans/genética , Tamanho Celular , Canais de Cloreto/genética , Células HEK293 , Humanos , Potenciais da Membrana , Mutagênese Sítio-Dirigida , Fosforilação , Mutação Puntual , Ligação Proteica , Proteínas Serina-Treonina Quinases/genética , Serina , Fatores de Tempo , Transfecção
17.
Cell Physiol Biochem ; 30(5): 1241-53, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23075671

RESUMO

BACKGROUND/AIMS: Tumor cells produce a large amount of acidic metabolites due to their high metabolic condition. However, cytosolic pH (pH(c)) of tumor cells is identical to or even slightly higher than that of normal cells. To maintain pH(c) at a normal or higher level, tumor cells would have to have higher expression and/or activity of H(+) transporting systems than normal cells. The purpose of the present study was to identify effects of ethyl-isopropyl amiloride (EIPA, an inhibitor of Na(+)/H(+) exchanger (NHE)) on proliferation of human gastric cancer MKN28 cells. METHODS: Effects of EIPA on proliferation, pH(c), [Cl(-)](c) and expression of proteins regulating cell cycle and MAPKs were studied in MKN28 expressing NHE exposed to EIPA for 48 h. RESULTS: EIPA suppressed proliferation of MKN28 cells by causing G(0)/G(1) arrest without any significant effects on pH(c), but associated with reduction of [Cl(-)](c). Although EIPA alone had no effects on pH(c), EIPA co-applied with DIDS (an inhibitor of Cl(-)/HCO(3)(-) exchangers; i.e., anion exchanger (AE) and Na+-driven Cl(-)/HCO(3)(-) exchanger (NDCBE)) reduced pH(c), suggesting that DIDS-sensitive Cl(-)/HCO(3)(-) transporters such as AE and/or NDCBE keep pH(c) normal by stimulating HCO(3)(-) uptake coupled with Cl(-) release under an NHE-inhibited condition. EIPA-induced lowered [Cl(-)](c) up-regulated expression of p21associated with phosphorylation of MAPKs, suppressing proliferation associated with G(0)/G(1) arrest. CONCLUSIONS: EIPA suppressed proliferation of MKN28 cells through up-regulation of p21 expression via reduction of [Cl(-)](c) as a result from DIDS-sensitive Cl(-)/HCO(3)(-) exchanger-mediated compensation for keeping pH(c) normal under an NHE-inhibited condition. This is the first study revealing that an NHE inhibitor suppressed the proliferation of cancer cells by reducing [Cl(-)](c) but not pH(c).


Assuntos
Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico/farmacologia , Amilorida/análogos & derivados , Antineoplásicos/farmacologia , Cloretos/metabolismo , Citosol/metabolismo , Fosfoproteínas/antagonistas & inibidores , Trocadores de Sódio-Hidrogênio/antagonistas & inibidores , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/patologia , Amilorida/química , Amilorida/farmacologia , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Canais de Cloreto/antagonistas & inibidores , Canais de Cloreto/metabolismo , Citosol/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Relação Estrutura-Atividade , Células Tumorais Cultivadas
18.
Am J Physiol Cell Physiol ; 300(3): C624-35, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21160027

RESUMO

Mammalian Ste20-like proline/alanine-rich kinase (SPAK) and oxidative stress-responsive 1 (OSR1) kinases phosphorylate and regulate cation-coupled Cl(-) cotransporter activity in response to cell volume changes. SPAK and OSR1 are activated via phosphorylation by upstream with-no-lysine (WNK) kinases. In Caenorhabditis elegans, the SPAK/OSR1 ortholog germinal center kinase (GCK)-3 binds to and regulates the activity of the cell volume- and meiotic cell cycle-dependent ClC anion channel CLH-3b. We tested the hypothesis that WNK kinases function in the GCK-3/CLH-3b signaling cascade. CLH-3b heterologously expressed in human embryonic kidney (HEK) cells was unaffected by coexpression with the single C. elegans WNK kinase, WNK-1, or kinase-dead WNK-1 dominant-negative mutants. RNA interference (RNAi) knockdown of the single Drosophila WNK kinase had no effect on the activity of CLH-3b expressed in Drosophila S2 cells. Similarly, RNAi silencing of C. elegans WNK-1 had no effect on basal or cell volume-sensitive activity of CLH-3b expressed endogenously in worm oocytes. Previous yeast 2-hybrid studies suggested that ERK kinases may function upstream of GCK-3. Pharmacological inhibition of ERK signaling disrupted CLH-3b activity in HEK cells in a GCK-3-dependent manner. RNAi silencing of the C. elegans ERK kinase MPK-1 or the ERK phosphorylating/activating kinase MEK-2 constitutively activated native CLH-3b. MEK-2 and MPK-1 play important roles in regulating the meiotic cell cycle in C. elegans oocytes. Cell cycle-dependent changes in MPK-1 correlate with the pattern of CLH-3b activation observed during oocyte meiotic maturation. We postulate that MEK-2/MPK-1 functions upstream from GCK-3 to regulate its activity during cell volume and meiotic cell cycle changes.


Assuntos
Proteínas de Caenorhabditis elegans/antagonistas & inibidores , Proteínas de Caenorhabditis elegans/fisiologia , Caenorhabditis elegans/metabolismo , Canais de Cloreto/antagonistas & inibidores , Canais de Cloreto/fisiologia , Proteínas de Drosophila/fisiologia , MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Ativação do Canal Iônico/fisiologia , Lisina/deficiência , Proteínas Serina-Treonina Quinases/fisiologia , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Linhagem Celular , Células Cultivadas , Proteínas de Drosophila/genética , Drosophila melanogaster , MAP Quinases Reguladas por Sinal Extracelular/genética , Técnicas de Silenciamento de Genes/métodos , Células HEK293 , Humanos , Ativação do Canal Iônico/genética , Lisina/fisiologia , Sistema de Sinalização das MAP Quinases/fisiologia , Proteínas Serina-Treonina Quinases/genética , Proteína Quinase 1 Deficiente de Lisina WNK
19.
J Biomed Biotechnol ; 2011: 978196, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22028593

RESUMO

Renal epithelial Na+ transport plays an important role in homeostasis of our body fluid content and blood pressure. Further, the Na+ transport in alveolar epithelial cells essentially controls the amount of alveolar fluid that should be kept at an appropriate level for normal gas exchange. The epithelial Na+ transport is generally mediated through two steps: (1) the entry step of Na+ via epithelial Na+ channel (ENaC) at the apical membrane and (2) the extrusion step of Na+ via the Na+, K+-ATPase at the basolateral membrane. In general, the Na+ entry via ENaC is the rate-limiting step. Therefore, the regulation of ENaC plays an essential role in control of blood pressure and normal gas exchange. In this paper, we discuss two major factors in ENaC regulation: (1) activity of individual ENaC and (2) number of ENaC located at the apical membrane.


Assuntos
Células Epiteliais/metabolismo , Canais Epiteliais de Sódio/metabolismo , Sódio/metabolismo , Animais , Humanos , Transporte de Íons , Camundongos
20.
J Cell Physiol ; 223(3): 764-70, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20205250

RESUMO

Recently, we reported that reduction of intracellular Cl(-) concentration ([Cl(-)](i)) inhibited proliferation of MKN28 gastric cancer cells by diminishing the transition rate from G(1) to S cell-cycle phase through upregulation of p21, cyclin-dependent kinase inhibitor, in a p53-independent manner. However, it is still unknown how intracellular Cl(-) regulates p21 expression level. In this study, we demonstrate that mitogen-activated protein kinases (MAPKs) are involved in the p21 upregulation and cell-cycle arrest induced by reduction of [Cl(-)](i). Culture of MKN28 cells in a low Cl(-) medium significantly induced phosphorylation (activation) of MAPKs (ERK, p38, and JNK) and G(1)/S cell-cycle arrest. To clarify the involvement of MAPKs in p21 upregulation and cell growth inhibition in the low Cl(-) medium, we studied effects of specific MAPKs inhibitors on p21 upregulation and G(1)/S cell-cycle arrest in MKN28 cells. Treatment with an inhibitor of p38 or JNK significantly suppressed p21 upregulation caused by culture in a low Cl(-) medium and rescued MKN28 cells from the low Cl(-)-induced G(1) cell-cycle arrest, whereas treatment with an ERK inhibitor had no significant effect on p21 expression or the growth of MKN28 cells in the low Cl(-) medium. These results strongly suggest that the intracellular Cl(-) affects the cell proliferation via activation of p38 and/or JNK cascades through upregulation of the cyclin-dependent kinase inhibitor (p21) in a p53-independent manner in MKN28 cells.


Assuntos
Cloretos/metabolismo , Espaço Intracelular/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neoplasias Gástricas/enzimologia , Neoplasias Gástricas/patologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Meios de Cultura/farmacologia , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Ativação Enzimática/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Espaço Intracelular/efeitos dos fármacos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Neoplasias Gástricas/genética
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