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1.
Intern Med ; 2024 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-38220187

RESUMEN

Semaglutide is a well-designed drug with a special coating that allows for oral administration to patients with type 2 diabetes mellitus. However, patients taking oral semaglutide complain of its bitter taste. We therefore considered suggesting that patients take oral semaglutide with hot water. When the hot water temperature was increased to above 46.0°C but below 52.0°C, no bitter taste was perceived, with the daily mean interstitial glucose level remaining at the target range. Taking oral semaglutide with hot water helps reduce its bitter taste.

2.
Cytotherapy ; 25(11): 1229-1235, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37486281

RESUMEN

BACKGROUND AIMS: With the aim of strengthening the scientific evidence of immune-cell therapy for cancer and further examining its safety, in October 2015, our hospital jointly established the Cancer Immune-Cell Therapy Evaluation Group (CITEG) with 39 medical facilities nationwide. METHODS: Medical information, such as patients' background characteristics, clinical efficacy and therapeutic cell types obtained from each facility, has been accumulated, analyzed and evaluated by CITEG. In this prospective study, we analyzed the adverse events associated with immune-cell therapy until the end of September 2022, and we presented our interim safety evaluation. RESULTS: A total of 3839 patients with malignant tumor were treated with immune-cell therapy, with a median age of 64 years (range, 13-97 years) and a male-to-female ratio of 1:1.08 (1846:1993). Most patients' performance status was 0 or 1 (86.8%) at the first visit, and 3234 cases (84.2%) were advanced or recurrent cases, which accounted for the majority. The total number of administrations reported in CITEG was 31890, of which 960 (3.0%) showed adverse events. The numbers of adverse events caused by treatment were 363 (1.8%) of 19661 administrations of αßT cell therapy, 9 of 845 administrations of γδT-cell therapy (1.1%) and 10 of 626 administrations of natural killer cell therapy (1.6%). The number of adverse events caused by dendritic cell (DC) vaccine therapy was 578 of 10748 administrations (5.4%), which was significantly larger than those for other treatments. Multivariate analysis revealed that αßT cell therapy had a significantly greater risk of adverse events at performance status 1 or higher, and patients younger than 64 years, women or adjuvant immune-cell therapy had a greater risk of adverse events in DC vaccine therapy. Injection-site reactions were the most frequently reported adverse events, with 449 events, the majority of which were associated with DC vaccine therapy. Among all other adverse events, fever (228 events), fatigue (141 events) and itching (131 events) were frequently reported. In contrast, three patients had adverse events (fever, abdominal pain and interstitial pneumonia) that required hospitalization, although they were weakly related to this therapy; rather, it was considered to be the effect of treatment for the primary disease. CONCLUSIONS: Immune-cell therapy for cancer was considered to be a safe treatment without serious adverse events.


Asunto(s)
Neoplasias , Humanos , Masculino , Femenino , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Estudios Prospectivos , Neoplasias/terapia , Inmunoterapia Adoptiva , Resultado del Tratamiento
3.
Diabetes Metab Syndr ; 17(7): 102806, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37343509

RESUMEN

AIMS: Sodium load increases endogenous glucagon-like peptide-1 (GLP-1) levels in humans. Therefore, patients with an increased amount of dietary sodium intake are supposed to have higher endogenous GLP-1 levels compared to those with less dietary sodium intake. Therefore, it can be hypothesized that patients with type 2 diabetes mellitus (T2DM) with more dietary sodium intake show better dipeptidyl peptidase-4 inhibitor (DPP-4i) effect on glycemic control because of the expected higher GLP-1 level. Thus, we performed a single-center cohort study to explore this idea. METHODS: Medical records of patients with T2DM prescribed DPP-4i in the last 11 years were investigated. Dietary sodium intake was measured before the DPP-4i prescription with Tanaka's formula using casual spot urine samples. The effect of DPP-4i on glycemic control was estimated by the subtraction of glycated hemoglobin (HbA1c) before DPP-4i initiation from HbA1c 1 year after DPP-4i administration. We analyzed 50 patients. RESULTS: DPP-4i improved HbA1c by -0.41% ± 0.66%. The effect of DPP-4i on glycemic control was significantly negatively correlated with the dietary sodium intake (r = -0.400). Thus, the more dietary sodium intake, the better the glycemic control by DPP-4i. CONCLUSIONS: Thus, patients can expect better plasma glucose control by DPP-4is if patients are taking increased dietary sodium intake.


Asunto(s)
Diabetes Mellitus Tipo 2 , Inhibidores de la Dipeptidil-Peptidasa IV , Sodio en la Dieta , Humanos , Inhibidores de la Dipeptidil-Peptidasa IV/uso terapéutico , Inhibidores de la Dipeptidil-Peptidasa IV/farmacología , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hemoglobina Glucada , Estudios de Cohortes , Hipoglucemiantes , Péptido 1 Similar al Glucagón , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas
4.
Diabetes Metab Syndr ; 17(1): 102704, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36621107

RESUMEN

BACKGROUND AND AIMS: Triiodothyronine reduces sodium glucose cotransporter 2 expression in the kidney and increased glucose excretion in urine of alloxan-induced diabetic rats. Free thyroxine is also negatively associated with islet beta-cell function in euthyroid subjects. However, the influence of sodium glucose cotransporter 2 inhibitor on thyroid function in patients with type 2 diabetes mellitus has not been established. METHODS: We investigated thyroid function in patients with type 2 diabetes mellitus in the presence or absence of sodium glucose cotransporter 2 inhibitor in a multicenter retrospective study conducted between 2019 and 2021. All participants visited the hospital monthly for type 2 diabetes mellitus treatment and plasma glucose and glycated hemoglobin level measurements. Furthermore, thyroid-stimulating hormone, free triiodothyronine, and free thyroxine levels were measured annually. RESULTS: Free triiodothyronine level and the free triiodothyronine:free thyroxine ratio in the group treated with sodium glucose cotransporter 2 inhibitor were significantly higher than the levels in the group not treated with sodium glucose cotransporter 2 inhibitor. Free triiodothyronine levels in the group treated with sodium glucose cotransporter 2 inhibitor were significantly higher than the levels in the group not treated with sodium glucose cotransporter 2 inhibitor (p = 0.040). Free thyroxine levels in the group treated with sodium glucose cotransporter 2 inhibitor were significantly lower than the levels in the group not treated with sodium glucose cotransporter 2 inhibitor (p = 0.002). Thyroid-stimulating hormone levels did not differ significantly between the two groups. CONCLUSIONS: Our findings show that sodium glucose cotransporter 2 inhibitor affects free triiodothyronine levels free thyroxine levels, and the free triiodothyronine:free thyroxine ratio.


Asunto(s)
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Estudios Retrospectivos , Tirotropina , Tiroxina , Triyodotironina , Humanos
6.
Protein Pept Lett ; 29(12): 1082-1087, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36173053

RESUMEN

BACKGROUND: Previously, AF-956, which contains S356 of FAM83G and an N-terminal antenna peptide for entry into colon cancer cells, is markedly antiproliferative compared to a control peptide (AF-859), which lacks the N-terminal antenna peptide, by inducing apoptosis via the inhibition of HSP27 phosphorylation at residues S15 and S82. OBJECTIVE: Because FAM83G-derived peptides are promising lead compounds for colon cancer treatment, we reanalyzed the effect of AG-066, which contains S356 of FAM83G and an N-terminal antenna peptide for entry into the liver cancer cells. METHODS: HepG2 liver cancer cells were incubated with either AF-859 or AG-066 at a concentration of 54 µM at 37 °C for 24, 48, and 72 h. The effects of AF-859 and AG-066 on the cultured HepG2 cells were estimated using an inverted light microscope. Furthermore, the DNA ladder method and the dead cell assay were performed by applying Live/Dead Cell Staining Kit II. Erk phosphorylation was estimated by western blotting. RESULTS: Treatment with AG-066 markedly reduced HepG2 viable cell counts compared to the AF- 859-treated HepG2 cells, as evident from the significantly increased number of dead cells in the culture medium. Additionally, AG-066 treatment increased cellular DNA laddering. We found no difference in Erk phosphorylation status between the AG-066- and AF-859-treated groups. CONCLUSION: This study illustrated that the peptide with a structure based on FAM83G functions as a spontaneous apoptosis inducer for liver cancer cells. Hence, it is a promising lead compound for the treatment of liver cancer.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias del Colon , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Apoptosis , Células Hep G2 , Péptidos/farmacología , Proliferación Celular
7.
Biomed Res ; 42(3): 95-102, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34092754

RESUMEN

Overexpressed TBC1D8B, a GTPase-activating protein, significantly reduced cultured HCT116 human colon cancer cell number. We tested N-terminal TBC1D8B, which is identical to wild type TBC1D8B from amino acid positions 1 to 427 and possesses a modified sequence from position 428 to 435 (ECGGLFLL) because of the introduction of a premature stop codon at position 436 to narrow down the minimum requirement element. The N-terminal TBC1D8B contains two GRAM domains but not the TBC domain essential for Rab-GTPase activity. The N-terminal TBC1D8B overexpression significantly reduced the cultured HCT116 cell number. When we tested C-terminal TBC1D8B, containing the portion of TBC1D8B absent in the N-terminal TBC1D8B, the cell number reduction was not observed. The N-terminal TBC1D8B overexpression significantly increased the coronin 1B expression and reduced the phosphorylation of serine 51 in eIF2α, respective markers of apoptosis and cell death/survival. Also, caspase 3 and poly ADP-ribose polymerase increased cleavage in suspended cells overexpressing the N-terminal TBC1D8B. Taken together, it is not the TBC domain for Rab-GTPase activity, but amino acids 1 to 435, including the two GRAM domains, that is enough for TBC1D8B to cause spontaneous apoptosis. TBC1D8B could be a potential anticancer therapeutic molecule.


Asunto(s)
Apoptosis , Proteínas de Unión al Calcio/fisiología , Proteínas de Transporte Vesicular/fisiología , Antineoplásicos/farmacología , Muerte Celular , Clonación Molecular , Codón de Terminación , Factor 2 Eucariótico de Iniciación/química , Proteínas Activadoras de GTPasa/química , Células HCT116 , Humanos , Fosforilación , Dominios Proteicos , Transfección
8.
Endocr J ; 68(10): 1237-1240, 2021 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-33980776

RESUMEN

Free triiodothyronine/free thyroxine (FT3/FT4) ratio is considered as an index of the activities of iodothyronine deiodinase types 1 and 2 (DIO1 and DIO2, respectively) and is reportedly associated with insulin resistance in euthyroid adults. Euthyroid women with polycystic ovary syndrome accompanied with insulin resistance have lesser deiodinase activities. Correspondingly, the serum insulin level in a fasted condition positively correlates with the FT3/FT4 ratio, and insulin depletion decreases the DIO2 activity in mice. Selected genetic variants in DIO1 are also associated with insulin resistance measures. Therefore, if insulin positively regulates DIO1 and DIO2, the FT3/FT4 ratio should decrease under impaired insulin action, and the casual insulin level and FT3/FT4 ratio should be negatively correlated. To evaluate this hypothesis, we conducted a single-center retrospective study between 2018 and 2021. All participants visited the selected hospitals monthly for type 2 diabetes mellitus treatment and casual plasma glucose and HbA1c level measurements. Furthermore, their casual serum insulin levels were measured annually. Meanwhile, we excluded patients treated with insulin injection. Ultimately, we evaluated 71 patients, which all exhibited euthyroid conditions. The FT3/FT4 ratio was independently associated with thyroid-stimulating hormone, casual plasma glucose, and casual insulin levels. In terms of the regression coefficients of the univariate linear regression analysis, the FT3/FT4 ratio negatively correlated with the casual serum insulin levels. Therefore, the risk of FT3/FT4 ratio underestimation should be considered when diagnosing Graves' disease, which is often accompanied with insulin resistance.


Asunto(s)
Diabetes Mellitus Tipo 2/sangre , Insulina/sangre , Tiroxina/sangre , Triyodotironina/sangre , Anciano , Anciano de 80 o más Años , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Yoduro Peroxidasa/metabolismo , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Yodotironina Deyodinasa Tipo II
9.
Endocr J ; 61(5): 523-7, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24705589

RESUMEN

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.


Asunto(s)
Transportador de Glucosa de Tipo 4/metabolismo , Glucosa/metabolismo , Insulina/farmacología , Podocitos/efectos de los fármacos , Podocitos/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Células 3T3-L1 , Adipocitos/efectos de los fármacos , Adipocitos/metabolismo , Animales , Células Cultivadas , Ratones , Proteína Oncogénica v-akt/metabolismo , Fosforilación , Procesamiento Proteico-Postraduccional , Transporte de Proteínas/efectos de los fármacos , Proteínas de Transporte Vesicular/genética
10.
Jpn J Infect Dis ; 66(5): 411-5, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24047740

RESUMEN

We evaluated the seroprevalence of vaccine-preventable infectious diseases among Japanese healthcare students to create immunization guidelines. Between 2007 and 2012, a total of 1746 Japanese medical, nursing, and paramedical students were serologically screened for measles, mumps, rubella, varicella, and hepatitis B virus (HBV) antibodies at the time of admission. In 2007, the seroprevalence of measles and mumps was 52.7% and 65.6%, respectively. The seroprevalence of measles dramatically increased to 96.6% in 2009 and was then sustained at >90%. The seroprevalence of mumps gradually increased to >80.0% between 2010 and 2012. The seroprevalence of rubella remained at >90% except in 2008 (85.6%), and the seroprevalence of varicella was sustained at >92% throughout 2007-2012. The seroprevalence of HBV antibody remained at <7% during 2007-2012. Although the seroprevalence of vaccine-preventable infectious diseases among Japanese healthcare students increased during the 2007-2012 study period, a substantial number of students were susceptible to vaccine-preventable infectious diseases. Therefore, we propose targeted immunization of Japanese healthcare students using serological screening prior to clinical training.


Asunto(s)
Anticuerpos Antivirales/sangre , Inmunoglobulina G/sangre , Virus del Sarampión/inmunología , Sarampión/epidemiología , Virus de la Parotiditis/inmunología , Paperas/epidemiología , Femenino , Virus de la Hepatitis B/inmunología , Herpesvirus Humano 3/inmunología , Humanos , Japón/epidemiología , Masculino , Virus de la Rubéola/inmunología , Estudios Seroepidemiológicos , Estudiantes del Área de la Salud , Adulto Joven
11.
Tohoku J Exp Med ; 230(2): 87-91, 2013 06.
Artículo en Inglés | MEDLINE | ID: mdl-23759899

RESUMEN

Screening of medical students and international students for tuberculosis (TB) at the time of admission is a key strategy to control and prevent the spread of infection on university campus and teaching hospitals because of the high risk of exposure to TB patients. The Mycobacterium tuberculosis antigen-specific T-cell interferon-γ release assays (IGRAs) are specific latent tuberculosis detection methods used in such groups. Currently, in Japan, there are no guidelines and no baseline data on IGRAs to evaluate the risk of TB in these high-risk groups. In order to evaluate TB risk at the time of admission in university campus and medical schools in Japan, a retrospective study was conducted. A total of 969 students (585 Japanese students and 384 international students) were screened for TB using the IGRAs at the time of admission. Eight Japanese students (0.9%) were positive for IGRAs, but none were diagnosed with active TB at the follow-up. In contrast, 30 international students (7.8%) were positive for IGRAs, including two students diagnosed with active TB during follow up. Positive ratio of IGRAs in international students was significantly higher than that of medical students at the time of admission. Here we propose a standard approach for TB screening with IGRAs at the time of admission for medical students and international students in Japan.


Asunto(s)
Ensayos de Liberación de Interferón gamma , Interferón gamma/sangre , Tuberculosis/sangre , Tuberculosis/diagnóstico , Adolescente , Adulto , Emigrantes e Inmigrantes , Femenino , Humanos , Internacionalidad , Japón , Masculino , Tamizaje Masivo/métodos , Estudios Retrospectivos , Factores de Riesgo , Facultades de Medicina , Estudiantes , Estudiantes de Medicina , Tuberculosis/etnología , Adulto Joven
12.
Protein Pept Lett ; 19(9): 997-1004, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22486620

RESUMEN

Nucleobindin-2 is a 420 amino acid EF-hand Ca²âº binding protein that can be further processed to generate an 82 amino terminal peptide termed Nesfatin-1. To examine the function of secreted Nucleobindin-2 in adipocyte differentiation, cultured 3T3-L1 cells were incubated with either 0 or 100 nM of GST, GST-Nucleobindin-2, prior to and during the initiation of adipocyte differentiation. Nucleobindin-2 treatment decreased neutral lipid accumulation (Oil-Red O staining) and expression of several marker genes for adipocyte differentiation (PPARγ, aP2, and adipsin). When Nucleobindin- 2 was constitutively secreted into cultured medium, cAMP content and insulin stimulated CREB phosphorylation were significantly reduced. On the other hand, intracellularly overexpressed Nucleobindin-2 failed to affect cAMP content and CREB phosphorylation. Taken together, these data indicate that secreted Nucleobindin-2 is a suppressor of adipocyte differentiation through inhibition of cAMP production and insulin signal.


Asunto(s)
Adipocitos/citología , Adipogénesis , Proteínas de Unión al Calcio/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Células 3T3-L1 , Adipocitos/metabolismo , Animales , Proteínas de Unión al Calcio/sangre , Proteínas de Unión al Calcio/química , AMP Cíclico/metabolismo , Proteínas de Unión al ADN/sangre , Proteínas de Unión al ADN/química , Humanos , Insulina/metabolismo , Ratones , Proteínas del Tejido Nervioso/sangre , Proteínas del Tejido Nervioso/química , Nucleobindinas , Ratas
13.
Endocrinology ; 153(7): 3308-19, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22514047

RESUMEN

Nucleobindin-2 is a 420-amino-acid EF-hand calcium-binding protein that undergoes proteolytic processing to generate an 82-amino-acid amino-terminal peptide termed nesfatin-1. To determine whether nucleobindin-2 has any biological function, nucleobindin-2 was either overexpressed or knocked down by short hairpin RNA in cultured CHO cells expressing the human insulin and epidermal growth factor (EGF) receptors (CHO/IE) and in 3T3-L1 cells. Reduction in nucleobindin-2 expression inhibited EGF-stimulated MAPK kinase (S217/S221) and Erk phosphorylation (T202/Y204). In contrast, there was no significant effect on EGF-stimulated EGF receptor phosphorylation, EGF receptor internalization, or 52-kDa Shc and c-Raf phosphorylation. Although kinase suppressor of Ras-1 and protein phosphatase 2A expression was not changed, intracellular calcium concentrations and PP2A activity was significantly increased in nucleobindin-2 knocked-down cells. Concomitant with these alterations in EGF-stimulated signaling, cell proliferation was significantly reduced in nucleobindin-2 knocked-down cells. Moreover, reduced nucleobindin-2 expression in 3T3-L1 preadipocytes resulted in a greater extent of 3T3-L1 cell adipocyte differentiation. Taken together, these data indicate that nucleobindin-2 regulates EGF-stimulated MAPK kinase/Erk signaling, cell proliferation, and adipocyte differentiation.


Asunto(s)
Adipocitos/citología , Proteínas de Unión al Calcio/biosíntesis , Proteínas de Unión al ADN/biosíntesis , Factor de Crecimiento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Proteínas del Tejido Nervioso/biosíntesis , Células 3T3-L1 , Animales , Células CHO , Calcio/metabolismo , Diferenciación Celular , Proliferación Celular , Cricetinae , Electroporación , Humanos , Ratones , Nucleobindinas , Proteína Fosfatasa 2/metabolismo , Receptor de Insulina/metabolismo , Transducción de Señal
14.
Allergy Asthma Clin Immunol ; 7(1): 15, 2011 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-21923950

RESUMEN

BACKGROUND: The fractional concentration of nitric oxide in exhaled air (FENO) is used as a biomarker of eosinophilic airway inflammation. FENO is increased in patients with asthma. The relationship between subjective asthma symptoms and airway inflammation is an important issue. We expected that the subjective asthma symptoms in women might be different from those in men. Therefore, we investigated the gender differences of asthma symptoms and FENO in a survey of asthma prevalence in university students. METHODS: The information about asthma symptoms was obtained from answers to the European Community Respiratory Health Survey (ECRHS) questionnaire, and FENO was measured by an offline method in 640 students who were informed of this study and consented to participate. RESULTS: The prevalence of asthma symptoms on the basis of data obtained from 584 students (266 men and 318 women), ranging in age from 18 to 24 years, was analyzed. Wheeze, chest tightness, an attack of shortness of breath, or an attack of cough within the last year was observed in 13.2% of 584 students. When 38.0 ppb was used as the cut-off value of FENO to make the diagnosis of asthma, the sensitivity was 86.8% and the specificity was 74.0%. FENO was ≥ 38.0 ppb in 32.7% of students. FENO was higher in men than in women. The prevalence of asthma symptoms estimated by considering FENO was 7.2%; the prevalence was greater in men (9.4%) than women (5.3%). A FENO ≥ 38.0 ppb was common in students who reported wheeze, but not in students, especially women, who reported cough attacks. CONCLUSIONS: The prevalence of asthma symptoms in university students age 18 to 24 years in Japan was estimated to be 7.2% on the basis of FENO levels as well as subjective symptoms. Gender differences were observed in both FENO levels and asthma symptoms reflecting the presence of eosinophilic airway inflammation. TRIAL REGISTRATION NUMBER: UMIN000003244.

15.
J Biol Chem ; 286(38): 33457-65, 2011 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-21813649

RESUMEN

The mechanism of TNF-α-induced insulin resistance has remained unresolved with evidence for down-regulation of insulin effector targets effects or blockade of proximal as well as distal insulin signaling events depending upon the dose, time, and cell type examined. To address this issue we examined the acute actions of TNF-α in differentiated 3T3L1 adipocytes. Acute (5-15 min) treatment with 20 ng/ml (~0.8 nm) TNF-α had no significant effect on IRS1-associated phosphatidylinositol 3-kinase. In contrast, TNF-α increased insulin-stimulated cyclin-dependent kinase-5 (CDK5) phosphorylation on tyrosine residue 15 through an Erk-dependent pathway and up-regulated the expression of the CDK5 regulator protein p35. In parallel, TNF-α stimulation also resulted in the phosphorylation and GTP loading of the Rho family GTP-binding protein, TC10α. TNF-α enhanced the depolymerization of cortical F-actin and inhibited insulin-stimulated glucose transporter-4 (GLUT4) translocation. Treatment with the MEK inhibitor, PD98059, blocked the TNF-α-induced increase in CDK5 phosphorylation and the depolymerization of cortical F-actin. Conversely, siRNA-mediated knockdown of CDK5 or treatment with the MEK inhibitor restored the impaired insulin-stimulated GLUT4 translocation induced by TNF-α. Furthermore, siRNA-mediated knockdown of p44/42 Erk also rescued the TNF-α inhibition of insulin-stimulated GLUT4 translocation. Together, these data demonstrate that TNF-α-mediated insulin resistance of glucose uptake can occur through a MEK/Erk-dependent activation of CDK5.


Asunto(s)
Quinasa 5 Dependiente de la Ciclina/metabolismo , Resistencia a la Insulina , Factor de Necrosis Tumoral alfa/farmacología , Células 3T3-L1 , Actinas/metabolismo , Animales , Flavonoides/farmacología , Transportador de Glucosa de Tipo 4/metabolismo , Guanosina Difosfato/metabolismo , Guanosina Trifosfato/metabolismo , Proteínas Sustrato del Receptor de Insulina/metabolismo , Ratones , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación/efectos de los fármacos , Polimerizacion/efectos de los fármacos , Interferencia de ARN/efectos de los fármacos , Receptor de Insulina/metabolismo , Proteínas de Unión al GTP rho/metabolismo
16.
J Biol Chem ; 283(51): 35455-63, 2008 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-18948252

RESUMEN

Insulin stimulation results in the activation of cyclin-dependent kinase-5 (CDK5) in lipid raft domains via a Fyn-dependent phosphorylation on tyrosine residue 15. In turn, activated CDK5 phosphorylates the Rho family GTP-binding protein TC10alpha on threonine 197 that is sensitive to the CDK5 inhibitor olomoucine and blocked by small interfering RNA-mediated knockdown of CDK5. The phosphorylation deficient mutant T197A-TC10alpha was not phosphorylated and excluded from the lipid raft domain, whereas the phosphorylation mimetic mutant (T197D-TC10alpha) was lipid raft localized. Insulin resulted in the GTP loading of T197D-TC10alpha but not T197A-TC10alpha and in parallel, T197D-TC10alpha but not T197A-TC10alpha depolymerized cortical actin and inhibited insulin-stimulated GLUT4 translocation. These data demonstrate that CDK5-dependent phosphorylation maintains TC10alpha in lipid raft compartments thereby disrupting cortical actin, whereas subsequent dephosphorylation of TC10alpha through inactivation of CDK5 allows for the re-assembly of F-actin. Because cortical actin reorganization is required for insulin-stimulated GLUT4 translocation, these data are consistent with a CDK5-dependent TC10alpha cycling between lipid raft and non-lipid raft compartments.


Asunto(s)
Quinasa 5 Dependiente de la Ciclina/metabolismo , Transportador de Glucosa de Tipo 4/metabolismo , Insulina/farmacología , Microdominios de Membrana/metabolismo , Proteínas de Unión al GTP rho/metabolismo , Células 3T3-L1 , Actinas/genética , Actinas/metabolismo , Animales , Quinasa 5 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 5 Dependiente de la Ciclina/genética , Inhibidores Enzimáticos/farmacología , Transportador de Glucosa de Tipo 4/genética , Insulina/genética , Insulina/metabolismo , Cinetina/farmacología , Microdominios de Membrana/genética , Ratones , Fosforilación/efectos de los fármacos , Fosforilación/genética , Transporte de Proteínas/efectos de los fármacos , Transporte de Proteínas/genética , Proteínas Proto-Oncogénicas c-fyn/genética , Proteínas Proto-Oncogénicas c-fyn/metabolismo , ARN Interferente Pequeño/genética , Proteínas de Unión al GTP rho/antagonistas & inhibidores , Proteínas de Unión al GTP rho/genética
17.
Nihon Eiseigaku Zasshi ; 63(3): 642-50, 2008 May.
Artículo en Japonés | MEDLINE | ID: mdl-18567370

RESUMEN

OBJECTIVES: The health benefits of resistance training for women have been well documented. However, few investigations have been reported on the immune responses to resistance training among young people. To determine the effects of resistance training on natural killer cell activity (NKCA) in young people, a study was conducted among healthy female university students. METHODS: The study was conducted with 22 healthy non athlete female university students (aged 19.8+/-1.3 years) who volunteered to participate in the study. Six women were assigned to exercise group (a) that carried out resistance training five or six times a week, another six women were assigned to exercise group (b) that carried out resistance training three or four times a week, and the remaining ten comprised, the control group (non exercise group). The exercise groups carried out resistance training for both the upper and lower parts of the body using ankle and wrist weights for 8 weeks. Blood samples were obtained at the onset of the study (before the start of any activity in the exercise groups) and at the conclusion of the training (8 weeks later) in order to determine NKCA. A physical fitness test and a muscle strength test were conducted on the subjects to assess the strength of the upper and lower parts of the body, muscular endurance, and flexibility. RESULTS: The mean NKCA at the conclusion of the training showed a significant increase in exercise group (b), even though there was no significant difference in NKCA in the non exercise group or in exercise group (a) between before and after the training. An improvement in physical fitness and muscle strength was observed in exercise group (a) and exercise group (b). CONCLUSIONS: This study showed that resistance training improved physical fitness, muscle strength, and NKCA in young female subjects. Regarding the effects of exercise frequency on NKCA, this study suggests that exercise carried out three of four times a week might be associated with an increase in NKCA.


Asunto(s)
Ejercicio Físico/fisiología , Células Asesinas Naturales/inmunología , Fuerza Muscular/fisiología , Aptitud Física/fisiología , Adulto , Femenino , Humanos , Estudiantes , Universidades
18.
Endocrinology ; 149(1): 40-9, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17916632

RESUMEN

Platelet-derived growth factor (PDGF) stimulation of skeletal muscle, cultured myotubes, and 3T3L1 adipocytes results in glucose transporter 4 (Glut4) translocation, albeit to a reduced level compared with insulin. To address the mechanism of PDGF action, we have determined that the Syntaxin 4 negative regulatory protein, Munc18c, undergoes PDGF-stimulated phosphorylation on tyrosine residue 521. The tyrosine phosphorylation of Munc18c on Y521 occurred concomitant with the dissociation of the Munc18c protein from Syntaxin 4 in a time frame consistent with Glut4 translocation. Moreover, expression of the wild-type Munc18c protein did not inhibit PDGF-induced Glut4 translocation, whereas expression of Y521A-Munc18c mutant was inhibitory and failed to dissociate from Syntaxin 4. In contrast, expression of either wild-type Munc18c or the Y521A-Munc18c mutant both resulted in a marked inhibition of insulin-stimulated Glut4 translocation. Together, these data demonstrate that one mechanism accounting for the PDGF induction of Glut4 translocation is the suppression of the Munc18c negative regulation of Syntaxin 4 function.


Asunto(s)
Adipocitos/metabolismo , Transportador de Glucosa de Tipo 4/metabolismo , Proteínas Munc18/metabolismo , Proteínas Munc18/fisiología , Factor de Crecimiento Derivado de Plaquetas/farmacología , Proteínas Tirosina Quinasas/metabolismo , Células 3T3-L1 , Adipocitos/efectos de los fármacos , Adipocitos/fisiología , Animales , Dominio Catalítico/efectos de los fármacos , Dominio Catalítico/fisiología , Diferenciación Celular/efectos de los fármacos , Insulina/farmacología , Ratones , Fosforilación , Unión Proteica/efectos de los fármacos , Transporte de Proteínas/efectos de los fármacos , Proteínas Qa-SNARE/metabolismo , Proteínas Qa-SNARE/fisiología , Tirosina/metabolismo
19.
Biochem Biophys Res Commun ; 356(1): 102-6, 2007 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-17336927

RESUMEN

Previously we identified an unusual potential dual Akt/protein kinase B consensus phosphorylation motif in the protein Synip (RxKxRS(97)xS(99)) with serine 99 as a unique Akt2, but not Akt1 or for Akt3, substrate phosphorylation site. Although we have previously reported that serine 99 to phenylalanine (S99F-Synip) resulted in a constitutive inhibition of insulin-stimulated Glut4 translocation, a recent report indicated that Synip serine 99 to alanine mutant (S99A-Synip) failed to inhibit insulin-stimulated Glut4 translocation [H. Sano, S. Kane, E. Sano, G.E. Lienhard, Synip phosphorylation does not regulate insulin-stimulated GLUT4 translocation, Biochem. Biophys. Res. Commun. 332 (2005) 880-884]. To address this apparent discrepancy, we have now examined the S99A-Synip mutant and find that this mutant behaves essentially identical to S99F-Synip in that overexpression inhibits insulin-stimulated Glut4 translocation and is incapable of undergoing insulin-stimulated Syntaxin4 dissociation. These data are consistent with Synip serine 99 phosphorylation required for insulin-stimulated Glut4 translocation.


Asunto(s)
Transportador de Glucosa de Tipo 4/metabolismo , Insulina/farmacología , Proteínas de Transporte Vesicular/metabolismo , Células 3T3-L1 , Adipocitos/citología , Adipocitos/efectos de los fármacos , Adipocitos/metabolismo , Sustitución de Aminoácidos , Animales , Western Blotting , Electroforesis , Transportador de Glucosa de Tipo 4/genética , Ratones , Mutación , Fosforilación , Unión Proteica/efectos de los fármacos , Transporte de Proteínas/efectos de los fármacos , Proteínas Qa-SNARE/genética , Proteínas Qa-SNARE/metabolismo , Transfección , Proteínas de Transporte Vesicular/genética , beta-Galactosidasa/metabolismo
20.
Nihon Eiseigaku Zasshi ; 61(3): 332-9, 2006 May.
Artículo en Japonés | MEDLINE | ID: mdl-16768164

RESUMEN

OBJECTIVES: To determine the relationship between lifestyle and hemorheology among young people, a study was conducted among healthy university students. Because few investigations have been reported on the relationship between lifestyle factors and hemorheology by gender in young people, we analyzed the effects of lifestyle on hemorheology by administering an assessment questionnaire and by measuring whole blood passage time using MC-FAN (Micro Channel array Flow ANalyzer) and hematological and blood biochemical variables for female and male university students. METHODS: The study was conducted with 40 healthy nonathlete subjects (20 females aged 19.9+/-1.3 years and 20 healthy males aged 20.6+/-1.4 years) who volunteered to participate in the study. The smoking, alcohol drinking, eating, and other habits of the subjects were investigated using a questionnaire. Blood was obtained to determine whole blood passage time and hematological and blood biochemical variables. RESULTS: The mean value of whole blood passage time was significantly shorter in females (43.4+/-5.2 sec/100 microl) than in males (58.2+/-13.6 sec/100 microl). The mean values of RBC, Hb, Ht, MCHC, Alb, TG, Cr, UA, K, Ca, Fe, AST and ALT were significantly lower in females than in males, and the mean value of HDL-C was significantly higher in females than in males. In females, Spearman's correlation coefficient showed a positive correlation between whole blood passage time and RBC, and a negative correlation between whole blood passage time and TG It also showed a positive correlation between whole blood passage time and Plt, and a negative correlation between whole blood passage time and Alb in males. Among the lifestyle factors, the mean value of whole blood passage time in females who consumed salt lightly was significantly longer than that in females who consumed salt moderately. The mean value of whole blood passage time in males who liked sweets was significantly longer than that in males who were neutral to sweets. CONCLUSIONS: The present study showed that whole blood passage time is shorter in females than in males for young people. This conforms to the pattern shown in previous studies which investigated blood passage time among the elderly and people in their prime of life. It is conceivable that females have a higher fluidity than males in all age brackets. Regarding the effects of lifestyle on hemorheology, the present study suggests that several lifestyle factors are related to whole blood passage time and their effects differ according to gender.


Asunto(s)
Hemorreología , Estilo de Vida , Estudiantes , Universidades , Adulto , Femenino , Humanos , Masculino , Descanso/fisiología , Caracteres Sexuales , Encuestas y Cuestionarios
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