Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 48
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Biochem Biophys Res Commun ; 675: 54-60, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37451218

RESUMEN

A disintegrin and metalloprotease 10 (ADAM10) regulates the expression of cell surface receptors such as tumor necrosis factor receptor 1, toll-like receptor 4, and the receptor for advanced glycation end products (RAGE) by cleaving their extracellular regions. To function as a sheddase, ADAM10 should translocate from the intracellular compartments to the cell surface, but the translocation mechanism remains unclear. In this study, we explored the possible role of adenosine monophosphate-activated protein kinase (AMPK) in the induction of ADAM10 shedding activity. In cultured human aortic endothelial cells (HAECs), 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR), an AMPK activator, boosted ADAM10 cell surface translocation and ectodomain shedding of RAGE. ADAM10 inhibition with GI 254023X and ADAM10 siRNA silencing both prevented AICAR-induced RAGE ectodomain shedding. AICAR increased AMPK phosphorylation as well. Both Compound C-mediated AMPK inhibition and AMPKα1-siRNA-mediated AMPK depletion suppressed AICAR-induced ADAM10 cell surface translocation and RAGE ectodomain shedding. On the other hand, siRNA knockdown of Rab14, a small GTPase that facilitates the intracellular trafficking of transmembrane proteins, prevented AICAR-induced ADAM10 cell surface translocation and RAGE ectodomain shedding. In conclusion, AMPK activation is an obvious inducer of ADAM10 shedding activity. Our findings suggest that AMPK boosts ADAM10 shedding activity in HAECs by promoting Rab14-dependent ADAM10 cell surface translocation.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Células Endoteliales , Humanos , Células Endoteliales/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Proteína ADAM10/metabolismo , Membrana Celular/metabolismo , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Receptor para Productos Finales de Glicación Avanzada/metabolismo , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas de Unión al GTP rab/metabolismo
2.
Neurourol Urodyn ; 42(2): 530-538, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36633527

RESUMEN

AIMS: Micromotion is an autonomous intramural movement of the bladder, and is believed to be an initial step in the generation of urinary urgency. Therefore, controlling micromotion may be a novel target in overactive bladder (OAB) treatment. However, developing micromotion treatment has been limited by the absence of a standardized animal model. We attempted to create a micromotion animal model and investigated the effectiveness of a ß3 -adrenoceptor agonist (CL316,243) on micromotion. METHODS: Bilateral major pelvic ganglia (MPGs) were excised in 18 male Sprague-Dawley rats, resulting in an almost completely denervated bladder. On postoperative Day 7, cystometry was performed. Rats were divided into three treatment groups: CL316,243; ß3- adrenoceptor antagonist (SR59230A) pretreated CL316,243; and a nonselective antimuscarinic agent (oxybutynin). Changes in micromotion were evaluated after the intra-arterial administration of each agent. RESULTS: Low-amplitude oscillations in intravesical pressure (micromotion) were observed 1 week after MPGs excision. Micromotion frequency significantly (p = 0.003) decreased (2.17 ± 3.54 times/5 min) with CL316,243 compared with vehicle (6.33 ± 1.97 times/5 min). Micromotion amplitude also decreased with CL316,243 (1.15 ± 1.93 cmH2 O) compared with vehicle (5.96 ± 5.12 cmH2 O), approaching conventional significance (p = 0.090). No significant decreases in frequency or amplitude were observed with oxybutynin treatment. CONCLUSIONS: Systemic administration of the ß3 -adrenoceptor agonist CL316,243 effectively controlled micromotion in bilateral MPGs-excised, almost completely denervated rat bladders. This result indicates that ß3 -adrenoceptor agonist may affect the bladder directly, suggesting that it might be effective for overall OAB, regardless of the presence or level of neurological deficits. Bilateral MPGs-excised rats are considered a plausible micromotion animal model suitable for future research.


Asunto(s)
Vejiga Urinaria Hiperactiva , Vejiga Urinaria , Animales , Masculino , Ratas , Agonistas de Receptores Adrenérgicos beta 3/farmacología , Ratas Sprague-Dawley , Receptores Adrenérgicos , Receptores Adrenérgicos beta 3
3.
BMC Pediatr ; 21(1): 504, 2021 11 11.
Artículo en Inglés | MEDLINE | ID: mdl-34763671

RESUMEN

BACKGROUND: Inflammatory bowel disease (IBD) is associated with an increased risk of Colorectal cancer (CRC), and its most important risk factors are the duration and extent of the disease. Pediatric-onset inflammatory bowel disease has a tendency for a more extensive, more severe, and longer predicted disease duration than adult-onset inflammatory bowel disease. This study aimed to identify the clinical characteristics of patients with CRC related to pediatric-onset IBD and consider the appropriateness of current surveillance endoscopy recommendations for the detection of premalignant lesions and early-stage CRC. METHODS: We searched a research platform based on the SUPREME electronic medical record data-mining system to identify cases of colorectal malignancy in patients with pediatric IBD that presented between 2000 and 2020. RESULTS: During the follow-up, 4 (1.29 per 1000 person years) out of 443 patients with PIBD was diagnosed with CRC. The median age at diagnosis of CRC was 18.5 (range: 15-24) years, and the median period from diagnosis of IBD to CRC was 9.42 (range: 0.44-11.96) years. The sigmoid colon was the most frequent location of CRC (in 3 of the 4 cases). Adenocarcinoma was the most common histological type (in 2 of the 4 cases). CONCLUSIONS: Patients with pediatric-onset IBD exhibited a much shorter disease duration than that of adult-onset IBD at the time of diagnosis of CRC, suggesting that surveillance endoscopy for the detection of precancerous lesions and early-stage cancer should be initiated earlier in pediatric patients than in adult patients.


Asunto(s)
Colitis Ulcerosa , Neoplasias Colorrectales , Enfermedad de Crohn , Enfermedades Inflamatorias del Intestino , Niño , Neoplasias Colorrectales/complicaciones , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/epidemiología , Enfermedad de Crohn/complicaciones , Enfermedad de Crohn/diagnóstico , Humanos , Enfermedades Inflamatorias del Intestino/complicaciones , Enfermedades Inflamatorias del Intestino/diagnóstico , Factores de Riesgo
4.
J Clin Lab Anal ; 35(1): e23586, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32969530

RESUMEN

BACKGROUND: Automated flow cytometry-based urine analyzer is increasingly being used to identify and enumerate cells and particles in urine specimens. It measures electrical conductivity which could be transformed to osmolality. Using this machine, all urine specimens could be screened for osmolality without requiring a separate dedicated device. We evaluated the performance of the new instrument, the UF-5000 (Sysmex Corporation), in the measurement of urine osmolality. METHODS: The precision of urine osmolality measurement by the UF-5000 was evaluated for 20 days and 4 times a day for 2 concentrations. The linearity and detection capability were evaluated according to the Clinical and Laboratory Standards Institute guidelines. For comparison, 270 random urine specimens from patients were tested simultaneously using the UF5000 and the OsmoPro micro-osmometer (Advanced instruments). RESULTS: The laboratory-based coefficient variations were less than 5%. Urine osmolality using the UF-5000 has a verified linear range (y = 1.097x + 16.91, R2  = .997). Within the comparison analysis, the mean difference was not large (-7.72%) but each differences were largely dispersed with 95% limits of agreement (LoA) from -70.5 to 55.06%, and the mean absolute difference -28.3 mOsm/kg with 95% LoA from -295.13 to 238.45 mOsm/kg. Cohen's kappa value was 0.54 (95% CI, 0.45-0.63). CONCLUSIONS: The UF-5000 measured conductivity and generated an acceptable quantitative analysis of urine osmolality. When compared with the results of the freezing point depression method used by the OsmoPro, a percentage of the measured urine osmolality by the UF-5000 was outside the allowable limit.


Asunto(s)
Automatización de Laboratorios , Citometría de Flujo , Urinálisis , Automatización de Laboratorios/métodos , Automatización de Laboratorios/normas , Conductividad Eléctrica , Citometría de Flujo/métodos , Citometría de Flujo/normas , Humanos , Concentración Osmolar , Urinálisis/métodos , Urinálisis/normas , Orina/química , Orina/citología
5.
J Korean Med Sci ; 36(9): e64, 2021 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-33686810

RESUMEN

BACKGROUND: In Korea, there were issues regarding the use of immunoassays for anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies to detect infection. So, we compared antibody results of eight kinds of commercial immunoassays using clinical remnant specimens. METHODS: We compared the results of several immunoassay kits tested on 40 serum samples from 15 confirmed patients and 86 remnant serum samples from clinical laboratory. Eight kinds of IVD kits-four enzyme-linked immunosorbent assay, two lateral flow rapid immunochromatographic assays, and two chemiluminescent immunoassays with one RUO kit were tested. RESULTS: Among 40 serum samples from 15 coronavirus disease 2019 (COVID-19) patients, 35 yielded at least one positive result for detecting antibodies in the combined assessment. There were inconsistent results in 12 (28%) samples by single immunoassay. Forty samples collected in 2019 before the first COVID-19 Korean case showed negative results except for one equivocal result. CONCLUSION: The discrepant results obtained with different immunoassay kits in this study show that serological assessment of SARS-CoV-2 by a single immunoassay requires caution not only in detecting infection but also in assessing immunologic status.


Asunto(s)
Anticuerpos Antivirales/sangre , COVID-19/diagnóstico , Inmunoensayo/métodos , SARS-CoV-2/inmunología , COVID-19/virología , Hospitalización , Humanos , Inmunoglobulina G/sangre , Juego de Reactivos para Diagnóstico , SARS-CoV-2/aislamiento & purificación
6.
Int J Mol Sci ; 22(5)2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33807864

RESUMEN

INTRODUCTION: Chronic inflammation and impaired neovascularization play critical roles in delayed wound healing in diabetic patients. To overcome the limitations of current diabetic wound (DBW) management interventions, we investigated the effects of a catechol-functionalized hyaluronic acid (HA-CA) patch combined with adipose-derived mesenchymal stem cells (ADSCs) in DBW mouse models. METHODS: Diabetes in mice (C57BL/6, male) was induced by streptozotocin (50 mg/kg, >250 mg/dL). Mice were divided into four groups: control (DBW) group, ADSCs group, HA-CA group, and HA-CA + ADSCs group (n = 10 per group). Fluorescently labeled ADSCs (5 × 105 cells/100 µL) were transplanted into healthy tissues at the wound boundary or deposited at the HA-CA patch at the wound site. The wound area was visually examined. Collagen content, granulation tissue thickness and vascularity, cell apoptosis, and re-epithelialization were assessed. Angiogenesis was evaluated by immunohistochemistry, quantitative real-time polymerase chain reaction, and Western blot. RESULTS: DBW size was significantly smaller in the HA-CA + ADSCs group (8% ± 2%) compared with the control (16% ± 5%, p < 0.01) and ADSCs (24% ± 17%, p < 0.05) groups. In mice treated with HA-CA + ADSCs, the epidermis was regenerated, and skin thickness was restored. CD31 and von Willebrand factor-positive vessels were detected in mice treated with HA-CA + ADSCs. The mRNA and protein levels of VEGF, IGF-1, FGF-2, ANG-1, PIK, and AKT in the HA-CA + ADSCs group were the highest among all groups, although the Spred1 and ERK expression levels remained unchanged. CONCLUSIONS: The combination of HA-CA and ADSCs provided synergistic wound healing effects by maximizing paracrine signaling and angiogenesis via the PI3K/AKT pathway. Therefore, ADSC-loaded HA-CA might represent a novel strategy for the treatment of DBW.


Asunto(s)
Tejido Adiposo/metabolismo , Vendajes , Diabetes Mellitus Experimental/terapia , Angiopatías Diabéticas/terapia , Ácido Hialurónico , Trasplante de Células Madre , Células Madre/metabolismo , Cicatrización de Heridas , Heridas y Lesiones/terapia , Tejido Adiposo/patología , Animales , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patología , Angiopatías Diabéticas/metabolismo , Angiopatías Diabéticas/patología , Femenino , Humanos , Ácido Hialurónico/química , Ácido Hialurónico/farmacología , Masculino , Ratones , Células Madre/patología , Heridas y Lesiones/metabolismo , Heridas y Lesiones/patología
7.
Biochem Biophys Res Commun ; 511(4): 780-786, 2019 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-30833075

RESUMEN

In septic shock, arginine vasopressin (AVP) is commonly used as a vasopressor to restore blood pressure. Exogenous AVP may have anti-inflammatory effects as well. We investigated whether AVP modulates the effects of tumor necrosis factor-α (TNF-α) in human aortic endothelial cells (HAECs). TNF-α stimulated intercellular adhesion molecule-1 expression, while AVP pretreatment attenuated this effect of TNF-α. Upon treatment with AVP, extracellular Ca2+ entered the cells rapidly through L-type calcium channels, which in turn induced cell surface translocation of a disintegrin and metalloprotease 10 (ADAM10) and ectodomain shedding of tumor necrosis factor receptor 1 (TNFR1). On the other hand, siRNA depletion of ADAM10 suppressed AVP-induced ectodomain shedding of TNFR1 and eliminated the inhibitory effect of AVP against TNF-α. Depletion of oxytocin receptor also abolished AVP-induced extracellular Ca2+ influx, AVP-induced ectodomain shedding of TNFR1 and the inhibitory effect of AVP against TNF-α. These findings suggest that AVP decreases the responsiveness of HAECs to TNF-α by inducing ADAM10-dependent ectodomain shedding of TNFR1. Extracellular Ca2+ influx through L-type calcium channels was essential for ADAM10 activation. This effect of AVP was mediated through the oxytocin receptor.


Asunto(s)
Arginina Vasopresina/farmacología , Células Endoteliales/efectos de los fármacos , Receptores Tipo I de Factores de Necrosis Tumoral/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Vasoconstrictores/farmacología , Proteína ADAM10/metabolismo , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Aorta/efectos de los fármacos , Aorta/metabolismo , Calcio/metabolismo , Línea Celular , Células Endoteliales/metabolismo , Humanos , Proteínas de la Membrana/metabolismo
8.
Ther Drug Monit ; 41(1): 75-85, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30507626

RESUMEN

BACKGROUND: Concentrations of 6-thioguanine (6TG) nucleotides and 6-methylmercaptopurine (6MMP) nucleotides in RBCs were measured using liquid chromatography-tandem mass spectrometry (LC-MS/MS). This assay was validated for clinical use and was applied to blood samples from patients taking mercaptopurine (6MP). METHODS: RBCs were hemolyzed and deproteinized using perchloric acid, followed by heating for the hydrolysis of nucleotides, and the resultant base was measured using LC-MS/MS. Precision, recovery, linearity, matrix effect, and limit of quantification was validated for clinical application. Our results were compared with another institution's established LC-MS/MS assay. We measured the concentrations of 6TG and 6MMP in RBCs of pediatric patients with acute lymphoblastic leukemia (ALL), and the clinical impact of those metabolites was investigated. RESULTS: The imprecision coefficient of variations of 6TG and 6MMP were 5.7%-8.1%, and the bias was within 5%. Lower limits of quantification were set at 54 ng/mL for 6TG and 1036 ng/mL for 6MMP. Correlation coefficients for 6TG and 6MMP were 0.997 and 1.0 in a comparison study. For clinical proof-of-concept, 74 blood samples were collected from 37 pediatric ALL patients receiving maintenance therapy. Concentration of 6TG ranged from 16.1 to 880 pmol/8 × 10 RBCs and that of 6MMP from 55 to 20,937 pmol/8 × 10 RBCs. The 6MP metabolites were not correlated with WBC or absolute neutrophil count. On the other hand, the higher 6MMP level was associated with elevated alanine aminotransferase and aspartate aminotransferase. CONCLUSIONS: In this study, an assay for the quantification of 6TG and 6MMP in RBCs was established and applied to pediatric ALL patients. Interindividual variability in 6MP metabolite concentrations was considerable and associated with elevation of liver enzymes, which may be useful in the clinical monitoring of 6MP maintenance therapy in pediatric ALL patients.


Asunto(s)
Antimetabolitos Antineoplásicos/farmacocinética , Eritrocitos/efectos de los fármacos , Nucleótidos/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Tioguanina/farmacocinética , Tioguanina/uso terapéutico , Adolescente , Antimetabolitos Antineoplásicos/sangre , Antimetabolitos Antineoplásicos/uso terapéutico , Niño , Preescolar , Cromatografía Liquida/métodos , Eritrocitos/metabolismo , Femenino , Humanos , Masculino , Mercaptopurina/análogos & derivados , Mercaptopurina/sangre , Mercaptopurina/metabolismo , Nucleótidos/sangre , Nucleótidos/uso terapéutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangre , Espectrometría de Masas en Tándem/métodos , Tioguanina/sangre
9.
Cell Physiol Biochem ; 43(6): 2434-2445, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29073626

RESUMEN

BACKGROUND/AIMS: We investigated how diosgenin, a steroidal sapogenin, has anti-tumor necrosis factor-α (TNF-α) effects in human aortic endothelial cells (HAECs). METHODS: Tumor necrosis factor receptor 1 (TNFR1) was assessed by Western blot analysis. Intracellular Ca2+ was measured using Fluo-4 AM. Immunofluorescence staining was performed for a disintegrin and metalloprotease 10 (ADAM10). RESULTS: Diosgenin (1 ∼ 100 nM) induced ectodomain shedding of TNFR1 within 30 min and attenuated TNF-α-induced intercellular adhesion molecule-1 (ICAM-1) expression. Upon treatment with diosgenin, extracellular Ca2+ entered into the cells via L-type calcium channels, whereas diosgenin-induced ectodomain shedding of TNFR1 was almost completely inhibited by BAPTA-AM (intracellular Ca2+ chelator), verapamil (L-type calcium channel antagonist) and the absence of extracellular Ca2+. Diosgenin caused translocation of ADAM10 to the cell surface, which was mediated by extracellular Ca2+ influx. Depletion of ADAM10 prevented diosgenin-induced ectodomain shedding of TNFR1 and abolished the inhibitory effect of diosgenin on TNF-α-induced ICAM-1 expression. Diosgenin did not induce extracellular Ca2+ influx and ectodomain shedding of TNFR1 in cells depleted of 1,25D3-membrane associated rapid response steroid-binding receptor (1,25D3-MARRS receptor/ERp57). CONCLUSION: Diosgenin elicits L-type calcium channel-mediated extracellular Ca2+ influx, and thereby induces ADAM10-mediated ectodomain shedding of TNFR1. This effect of diosgenin was exerted through 1,25D3-MARRS receptor/ERp57.


Asunto(s)
Proteína ADAM10/metabolismo , Transporte Biológico/efectos de los fármacos , Diosgenina/farmacología , Proteína Disulfuro Isomerasas/metabolismo , Receptores Tipo I de Factores de Necrosis Tumoral/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Proteína ADAM10/antagonistas & inhibidores , Proteína ADAM10/genética , Calcio/química , Calcio/metabolismo , Canales de Calcio Tipo L/química , Canales de Calcio Tipo L/metabolismo , Membrana Celular/metabolismo , Células Cultivadas , Ácido Egtácico/análogos & derivados , Ácido Egtácico/química , Ácido Egtácico/farmacología , Células Endoteliales/citología , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Humanos , Molécula 1 de Adhesión Intercelular/metabolismo , Microscopía Confocal , Proteína Disulfuro Isomerasas/antagonistas & inhibidores , Proteína Disulfuro Isomerasas/genética , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Verapamilo/farmacología
11.
Cell Physiol Biochem ; 38(5): 1963-74, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27161171

RESUMEN

BACKGROUND/AIMS: We investigated the mechanism underlying anti-tumor necrosis factor-α (TNF-α) effects of epigallocatechin-3-gallate (EGCG) in human aortic endothelial cells. METHODS: Tumor necrosis factor receptor 1 (TNFR1) was assessed by Western blot analysis. Cytosolic Ca2+ was measured using Fluo-4 AM. A disintegrin and metalloprotease 10 (ADAM10) was localized by immunofluorescence staining. RESULTS: EGCG caused ectodomain shedding of TNFR1 within 30 min and attenuated TNF-α-induced endothelin-1 (ET-1) expression. EGCG-induced TNFR1 ectodomain shedding was prevented by BAPTA-AM (intracellular Ca2+ chelator), but not by the absence of extracellular Ca2+. In physiologic extracellular Ca2+ concentration, EGCG markedly increased cytosolic Ca2+. Even in the absence of extracellular Ca2+, EGCG raised cytosolic Ca2+, though less potently. siRNA depletion of ADAM10 prevented EGCG-induced ectodomain shedding of TNFR1 and also diminished the inhibitory effect of EGCG on TNF-α-induced ET-1 expression. EGCG caused translocation of ADAM10 to the plasma membrane, and this effect was prevented by BAPTA-AM. Besides extracellular Ca2+ influx, release of intracellular stored Ca2+ caused ADAM10-dependent ectodomain shedding of TNFR1. CONCLUSION: EGCG decreases the responsiveness of cells to TNF-α by causing ADAM10-dependent ectodomain shedding of TNFR1. This effect was attributed to its property to increase cytosolic Ca2+ through both extracellular Ca2+ influx and release of stored Ca2+.


Asunto(s)
Catequina/análogos & derivados , Expresión Génica/efectos de los fármacos , Receptores Tipo I de Factores de Necrosis Tumoral/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Proteína ADAM10/antagonistas & inhibidores , Proteína ADAM10/genética , Proteína ADAM10/metabolismo , Western Blotting , Calcio/metabolismo , Catequina/farmacología , Línea Celular , Membrana Celular/metabolismo , Ácido Egtácico/análogos & derivados , Ácido Egtácico/farmacología , Células Endoteliales/citología , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Endotelina-1/metabolismo , Humanos , Microscopía Fluorescente , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Receptores Tipo I de Factores de Necrosis Tumoral/química
13.
Am J Physiol Renal Physiol ; 308(3): F226-36, 2015 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-25428127

RESUMEN

It has been suggested that endoplasmic reticulum (ER) stress facilitates fibrotic remodeling. Therefore, modulation of ER stress may serve as one of the possible therapeutic approaches to renal fibrosis. We examined whether and how activation of AMP-activated protein kinase (AMPK) suppressed ER stress induced by chemical ER stress inducers [tunicamycin (TM) and thapsigargin (TG)] and also nonchemical inducers in tubular HK-2 cells. We further investigated the in vivo effects of AMPK on ER stress and renal fibrosis. Western blot analysis, immunofluorescence, small interfering (si)RNA experiments, and immunohistochemical staining were performed. Metformin (the best known clinical activator of AMPK) suppressed TM- or TG-induced ER stress, as shown by the inhibition of TM- or TG-induced upregulation of glucose-related protein (GRP)78 and phosphorylated eukaryotic initiation factor-2α through induction of heme oxygenase-1. Metformin inhibited TM- or TG-induced epithelial-mesenchymal transitions as well. Compound C (AMPK inhibitor) blocked the effect of metformin, and 5-aminoimidazole-4-carboxamide-1ß riboside (another AMPK activator) exerted the same effects as metformin. Transfection with siRNA targeting AMPK blocked the effect of metformin. Consistent with the results of cell culture experiments, metformin reduced renal cortical GRP78 expression and increased heme oxygenase-1 expression in a mouse model of ER stress-induced acute kidney injury by TM. Activation of AMPK also suppressed ER stress by transforming growth factor-ß, ANG II, aldosterone, and high glucose. Furthermore, metformin reduced GRP78 expression and renal fibrosis in a mouse model of unilateral ureteral obstruction. In conclusion, AMPK may serve as a promising therapeutic target through reducing ER stress and renal fibrosis.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Estrés del Retículo Endoplásmico/efectos de los fármacos , Hemo-Oxigenasa 1/metabolismo , Enfermedades Renales/tratamiento farmacológico , Metformina/farmacología , Animales , Modelos Animales de Enfermedad , Chaperón BiP del Retículo Endoplásmico , Activación Enzimática , Fibrosis/metabolismo , Proteínas de Choque Térmico/metabolismo , Humanos , Masculino , Ratones Endogámicos C57BL , Tunicamicina/farmacología
14.
Circ J ; 78(3): 656-61, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24334637

RESUMEN

BACKGROUND: Microalbuminuria is known as a risk factor for hypertension. Recently it was suggested that urine albumin-to-creatinine ratio (UACR), even within the normal range, can be associated with hypertension, but the temporal relationship between normal range UACR and hypertension was not confirmed. Therefore the aim of this study was to verify an association between normal range UACR and the development of hypertension in Korean men. METHODS AND RESULTS: This prospective cohort study was performed on 1,284 initially non-hypertensive Korean men. The total follow-up period was 4,109.5 person-years and the mean follow-up period was 3.2±1.51 years. Cox proportional hazards model was used to estimate the hazard ratios (HR) for the risk of hypertension development. After adjusting for multiple covariates, the HR (95% confidence interval [CI]) for incident hypertension, comparing the second to the fourth quartiles of UACR level to the first quartile, were 1.35 (95% CI: 0.93-1.97), 1.55 (95% CI: 1.07-2.25) and 1.89 (95% CI: 1.31-2.71), respectively (P for trend=0.001). CONCLUSIONS: High UACR within the normal range was significantly associated with hypertension development. Furthermore, this association remained significant after adjusting for multiple baseline covariates.


Asunto(s)
Albuminuria/orina , Creatinina/orina , Hipertensión/orina , Adulto , Albuminuria/epidemiología , Estudios de Seguimiento , Humanos , Hipertensión/epidemiología , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo
16.
Nephron Exp Nephrol ; 126(3): 127-40, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24863135

RESUMEN

BACKGROUND: Endoplasmic reticulum (ER) stress has been implicated in inducing epithelial-mesenchymal transition (EMT). ER stress is also known to induce autophagy. However, it is unclear whether ER stress-induced autophagy contributes to EMT. We hypothesized that ER stress might induce EMT through autophagy via activation of c-Src kinase in tubular epithelial cells. METHOD: All experiments were performed using HK-2 cells. Protein expression was measured by Western blot analysis. Immunofluorescence and small interfering RNA (siRNA) experiments were performed. RESULTS: Chemical ER stress inducers such as tunicamycin (TM, 0.2 µM) and thapsigargin (TG, 0.2 µM) induced EMT, as shown by upregulation of α-smooth muscle actin and downregulation of E-cadherin. ER stress inhibitors such as 4-PBA and salubrinal suppressed both TM- and TG-induced EMT. TM and TG also induced autophagy, as evidenced by upregulation of LC3-II and beclin-1, which were abolished by pretreatment with ER stress inhibitors. Transfection with siRNA targeting ER stress protein (IRE-1) blocked the TM- or TG-induced EMT and autophagy. Autophagy inhibitors such as 3-methyladenine and bafilomycin inhibited the TM- or TG-induced EMT. Transfection with siRNA targeting autophagy protein (beclin-1) also blocked the TM- or TG-induced EMT. Both TM and TG induced activation of c-Src kinase. Inhibitor of c-Src kinase (PP2) suppressed the TM- or TG-induced autophagy and EMT. CONCLUSION: ER stress by TM or TG induced EMT through autophagy via activation of c-Src kinase in tubular epithelial cells.


Asunto(s)
Autofagia/fisiología , Estrés del Retículo Endoplásmico/fisiología , Transición Epitelial-Mesenquimal/fisiología , Túbulos Renales Proximales/enzimología , Familia-src Quinasas/metabolismo , Autofagia/efectos de los fármacos , Proteína Tirosina Quinasa CSK , Línea Celular , Estrés del Retículo Endoplásmico/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Activación Enzimática/fisiología , Transición Epitelial-Mesenquimal/efectos de los fármacos , Humanos , Túbulos Renales Proximales/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Familia-src Quinasas/antagonistas & inhibidores
17.
Biol Pharm Bull ; 37(10): 1633-40, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25273386

RESUMEN

Tryptanthrin [6,12-dihydro-6,12-dioxoindolo-(2,1-b)-quinazoline], originally isolated from Isatidis radix, has been characterized as having anti-microbial and anti-tumor activities. It is well-known that excess oxidative stress is one of the major factors causing cell damage in the liver. This study investigated the cytoprotective effects and molecular mechanism of tryptanthrin against tert-butyl hydroperoxide (tBHP)-induced oxidative stress in human hepatocyte-derived HepG2 cells. Tryptanthrin pre-treatment blocked the reactive oxygen species production, mitochondrial dysfunction, and cell death induced by tBHP. Moreover, tryptanthrin reversed tBHP-induced GSH reduction. This study also confirmed the activation of nuclear factor erythroid 2-related factor 2 (Nrf2) by tryptanthrin as a plausible molecular mechanism for its cytoprotective effects. Specifically, tryptanthrin treatment induced nuclear translocation and transactivation of Nrf2 as well as phosphorylation of extracellular signal-regulated kinase (ERK), a potential upstream kinase of Nrf2. Tryptanthrin also up-regulated the expression of the heme oxygenase 1 and glutamate-cysteine ligase catalytic subunits, which are representative target genes of Nrf2. Moreover, inhibitor of ERK was used to verify the important role of the ERK-Nrf2 pathway in the hepatoprotective effects of tryptanthrin. In conclusion, this study demonstrated that tryptanthrin protects hepatocytes against oxidative stress through the activation of the ERK/Nrf2 pathway in HepG2 cells.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Hepatocitos/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo/efectos de los fármacos , Quinazolinas/farmacología , Activación Enzimática/efectos de los fármacos , Activación Enzimática/fisiología , Células Hep G2 , Hepatocitos/metabolismo , Humanos , Sistema de Señalización de MAP Quinasas/fisiología , Estrés Oxidativo/fisiología
18.
ScientificWorldJournal ; 2014: 185156, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25136649

RESUMEN

Authentication is an important security mechanism for detecting forged messages in a sensor network. Each cluster head (CH) in dynamic key distribution schemes forwards a key dissemination message that contains encrypted authentication keys within its cluster to next-hop nodes for the purpose of authentication. The forwarding path of the key dissemination message strongly affects the number of nodes to which the authentication keys in the message are actually distributed. We propose a routing method for the key dissemination messages to increase the number of nodes that obtain the authentication keys. In the proposed method, each node selects next-hop nodes to which the key dissemination message will be forwarded based on secret key indexes, the distance to the sink node, and the energy consumption of its neighbor nodes. The experimental results show that the proposed method can increase by 50-70% the number of nodes to which authentication keys in each cluster are distributed compared to geographic and energy-aware routing (GEAR). In addition, the proposed method can detect false reports earlier by using the distributed authentication keys, and it consumes less energy than GEAR when the false traffic ratio (FTR) is ≥ 10%.


Asunto(s)
Redes de Comunicación de Computadores , Algoritmos , Tecnología Inalámbrica
20.
Front Endocrinol (Lausanne) ; 14: 1287789, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38089603

RESUMEN

Background: This study aimed to investigate the effects of a collagen endometrial patch (EM patch) loaded with adipose-derived mesenchymal stem cells (ADSCs) on endometrial regeneration in a rat model with thin endometrium. Materials and methods: Thin endometrium was induced in female rats and divided into treatment groups as outlined: control, group 1(G1), local injection of ADSCs into the uterus, group 2 (G2), an EM patch without ADSCs, group 3 (G3), and an EM patch loaded with ADSCs, group 4 (G4). The rats were euthanized at either two weeks or four weeks after modeling and treatment followed by histological and biochemical analyses to examine the regenerative effects on the injured endometrium. Results: Transplantation of the ADSC-loaded EM patch significantly promoted endometrial proliferation and increased the luminal epithelial area. Two weeks after treatment, the mean number of von Villebrand factor (vWF)+ or cluster of differentiation (CD) 31+-stained blood vessels was significantly higher in G4 than in G1 and G2. The mRNA and protein expression levels of TGF-ß and FGF2 were significantly upregulated in G4 compared to those in the control. G4 exhibited significantly increased LIF mRNA levels and immunoreactivity compared with the other groups at both two weeks and four weeks after treatment. Cell tracking after ADSCs treatment revealed the presence of a substantial number of ADSCs grafted in the uterine tissues of G4, whereas a low number of ADSCs that were focally clustered were present in G2. Conclusion: Transplantation of EM patches loaded with ADSCs resulted in the histological and biochemical restoration of an injured endometrium. The strategic integration of EM patches and ADSCs holds significant promise as an innovative therapeutic approach for effectively treating impaired endometrial conditions.


Asunto(s)
Células Madre Mesenquimatosas , Regeneración , Ratas , Femenino , Animales , Ratas Sprague-Dawley , Endometrio/patología , Colágeno/metabolismo , ARN Mensajero/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA