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1.
Braz. j. med. biol. res ; 46(8): 659-669, ago. 2013. graf
Artículo en Inglés | LILACS | ID: lil-684523

RESUMEN

Chronic inflammation induced by amyloid-beta (Aβ) plays a key role in the development of age-related macular degeneration (AMD), and matrix metalloproteinase-9 (MMP-9), interleukin (IL)-6, and IL-8 may be associated with chronic inflammation in AMD. Sirtuin 1 (SIRT1) regulates inflammation via inhibition of nuclear factor-kappa B (NF-κB) signaling, and resveratrol has been reported to prevent Aβ-induced retinal degeneration; therefore, we investigated whether this action was mediated via activation of SIRT1 signaling. Human adult retinal pigment epithelial (RPE) cells were exposed to Aβ, and overactivation and knockdown of SIRT1 were performed to investigate whether SIRT1 is required for abrogating Aβ-induced inflammation. We found that Aβ-induced RPE barrier disruption and expression of IL-6, IL-8, and MMP-9 were abrogated by the SIRT1 activator SRT1720, whereas alterations induced by Aβ in SIRT1-silenced RPE cells were not attenuated by SRT1720. In addition, SRT1720 inhibited Aβ-mediated NF-κB activation and decrease of the NF-κB inhibitor, IκBα. Our findings suggest a protective role for SIRT1 signaling in Aβ-dependent retinal degeneration and inflammation in AMD.


Asunto(s)
Adulto , Humanos , Péptidos beta-Amiloides/metabolismo , Inflamación/inducido químicamente , Degeneración Macular/prevención & control , FN-kappa B/metabolismo , Epitelio Pigmentado de la Retina/efectos de los fármacos , Transducción de Señal/fisiología , Sirtuina 1/fisiología , Antioxidantes/farmacología , Barrera Hematorretinal/fisiopatología , Supervivencia Celular/efectos de los fármacos , Pruebas de Enzimas/métodos , Silenciador del Gen , /farmacología , /metabolismo , /metabolismo , Degeneración Macular/inducido químicamente , Degeneración Macular/fisiopatología , Metaloproteinasa 9 de la Matriz/metabolismo , FN-kappa B/efectos de los fármacos , Cultivo Primario de Células , Reacción en Cadena en Tiempo Real de la Polimerasa , Interferencia de ARN , Epitelio Pigmentado de la Retina/metabolismo , Estilbenos/farmacología
2.
Braz. j. med. biol. res ; 46(8): 650-658, ago. 2013. graf
Artículo en Inglés | LILACS | ID: lil-684524

RESUMEN

Cisplatin resistance remains one of the major obstacles when treating epithelial ovarian cancer. Because oxaliplatin and nedaplatin are effective against cisplatin-resistant ovarian cancer in clinical trials and signal transducer and activator of transcription 3 (STAT3) is associated with cisplatin resistance, we investigated whether overcoming cisplatin resistance by oxaliplatin and nedaplatin was associated with the STAT3 pathway in ovarian cancer. Alamar blue, clonogenic, and wound healing assays, and Western blot analysis were used to compare the effects of platinum drugs in SKOV-3 cells. At an equitoxic dose, oxaliplatin and nedaplatin exhibited similar inhibitory effects on colony-forming ability and greater inhibition on cell motility than cisplatin in ovarian cancer. Early in the time course of drug administration, cisplatin increased the expression of pSTAT3 (Tyr705), STAT3α, VEGF, survivin, and Bcl-XL, while oxaliplatin and nedaplatin exhibited the opposite effects, and upregulated pSTAT3 (Ser727) and STAT3β. The STAT3 pathway responded early to platinum drugs associated with cisplatin resistance in epithelial ovarian cancer and provided a rationale for new therapeutic strategies to reverse cisplatin resistance.


Asunto(s)
Animales , Humanos , Ratas , Antineoplásicos/administración & dosificación , Resistencia a Antineoplásicos/fisiología , Neoplasias Glandulares y Epiteliales/tratamiento farmacológico , Neoplasias Ováricas/tratamiento farmacológico , /metabolismo , Transducción de Señal/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/genética , Línea Celular Tumoral , Ensayos de Migración Celular/métodos , Proliferación Celular/efectos de los fármacos , Cisplatino/administración & dosificación , Resistencia a Antineoplásicos/efectos de los fármacos , Expresión Génica/efectos de los fármacos , Proteínas Inhibidoras de la Apoptosis/genética , Compuestos Organoplatinos/administración & dosificación , Oxazinas/farmacología , Factor A de Crecimiento Endotelial Vascular/genética , Xantenos/farmacología , Proteína bcl-X/genética
3.
Braz. j. med. biol. res ; 46(8): 643-649, ago. 2013. graf
Artículo en Inglés | LILACS | ID: lil-684525

RESUMEN

MP [4-(3′,3′-dimethylallyloxy)-5-methyl-6-methoxyphthalide] was obtained from liquid culture of Pestalotiopsis photiniae isolated from the Chinese Podocarpaceae plant Podocarpus macrophyllus. MP significantly inhibited the proliferation of HeLa tumor cell lines. After treatment with MP, characteristic apoptotic features such as DNA fragmentation and chromatin condensation were observed in DAPI-stained HeLa cells. Flow cytometry showed that MP induced G1 cell cycle arrest and apoptosis in a dose-dependent manner. Western blotting and real-time reverse transcription-polymerase chain reaction were used to investigate protein and mRNA expression. MP caused significant cell cycle arrest by upregulating the cyclin-dependent kinase inhibitor p27KIP1 protein and p21CIP1 mRNA levels in HeLa cells. The expression of p73 protein was increased after treatment with various MP concentrations. mRNA expression of the cell cycle-related genes, p21CIP1 , p16INK4a and Gadd45α, was significantly upregulated and mRNA levels demonstrated significantly increased translation of p73, JunB, FKHR, and Bim. The results indicate that MP may be a potential treatment for cervical cancer.


Asunto(s)
Humanos , Apoptosis/efectos de los fármacos , Benzofuranos/administración & dosificación , Endófitos/química , Puntos de Control de la Fase G1 del Ciclo Celular/efectos de los fármacos , Xylariales/química , Proteínas Reguladoras de la Apoptosis/genética , Benzofuranos/aislamiento & purificación , Proteínas de Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , /efectos de los fármacos , /efectos de los fármacos , Proteínas de Unión al ADN/efectos de los fármacos , Citometría de Flujo , Factores de Transcripción Forkhead/efectos de los fármacos , Cycadopsida , /efectos de los fármacos , Células HeLa , Proteínas Nucleares/efectos de los fármacos , Reacción en Cadena en Tiempo Real de la Polimerasa , Transcripción Genética , Factores de Transcripción/efectos de los fármacos , Proteínas Supresoras de Tumor/efectos de los fármacos
4.
Braz. j. med. biol. res ; 46(8): 722-727, ago. 2013. tab, graf
Artículo en Inglés | LILACS | ID: lil-684526

RESUMEN

Huntington's disease (HD) is a neurologic disorder that is not completely understood; its fundamental physiological mechanisms and chemical effects remain somewhat unclear. Among these uncertainties, we can highlight information about the concentrations of brain metabolites, which have been widely discussed. Concentration differences in affected, compared to healthy, individuals could lead to the development of useful tools for evaluating the progression of disease, or to the advance of investigations of different/alternative treatments. The aim of this study was to compare the thalamic concentration of metabolites in HD patients and healthy individuals using magnetic resonance spectroscopy. We used a 2.0-Tesla magnetic field, repetition time of 1500 ms, and echo time of 135 ms. Spectra from 40 adult HD patients and 26 control subjects were compared. Quantitative analysis was performed using the LCModel method. There were statistically significant differences between HD patients and controls in the concentrations of N-acetylaspartate+N-acetylaspartylglutamate (NAA+NAAG; t-test, P<0.001), and glycerophosphocholine+phosphocholine (GPC+PCh; t-test, P=0.001) relative to creatine+phosphocreatine (Cr+PCr). The NAA+NAAG/Cr+PCr ratio was decreased by 9% and GPC+PCh/Cr+PCr increased by 17% in patients compared with controls. There were no correlations between the concentration ratios and clinical features. Although these results could be caused by T1 and T2 changes, rather than variations in metabolite concentrations given the short repetition time and long echo time values used, our findings point to thalamic dysfunction, corroborating prior evidence.


Asunto(s)
Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Enfermedad de Huntington/metabolismo , Espectroscopía de Resonancia Magnética , Enfermedades Talámicas/metabolismo , Tálamo/fisiopatología , Ácido Aspártico/análisis , Ácido Aspártico/análogos & derivados , Estudios de Casos y Controles , Creatina/análisis , Deuterio , Dipéptidos/análisis , Glicerilfosforilcolina/análisis , Actividad Motora , Fosfocreatina/análisis , Fosforilcolina/análisis , Repeticiones de Trinucleótidos , Enfermedades Talámicas/diagnóstico
5.
Braz. j. med. biol. res ; 46(8): 708-714, ago. 2013. tab, graf
Artículo en Inglés | LILACS | ID: lil-684527

RESUMEN

Our objective was to investigate the protective effect of Lawesson's reagent, an H2S donor, against alendronate (ALD)-induced gastric damage in rats. Rats were pretreated with saline or Lawesson's reagent (3, 9, or 27 µmol/kg, po) once daily for 4 days. After 30 min, gastric damage was induced by ALD (30 mg/kg) administration by gavage. On the last day of treatment, the animals were killed 4 h after ALD administration. Gastric lesions were measured using a computer planimetry program, and gastric corpus pieces were assayed for malondialdehyde (MDA), glutathione (GSH), proinflammatory cytokines [tumor necrosis factor (TNF)-α and interleukin (IL)-1β], and myeloperoxidase (MPO). Other groups were pretreated with glibenclamide (5 mg/kg, ip) or with glibenclamide (5 mg/kg, ip)+diazoxide (3 mg/kg, ip). After 1 h, 27 µmol/kg Lawesson's reagent was administered. After 30 min, 30 mg/kg ALD was administered. ALD caused gastric damage (63.35±9.8 mm2); increased levels of TNF-α, IL-1β, and MDA (2311±302.3 pg/mL, 901.9±106.2 pg/mL, 121.1±4.3 nmol/g, respectively); increased MPO activity (26.1±3.8 U/mg); and reduced GSH levels (180.3±21.9 µg/g). ALD also increased cystathionine-γ-lyase immunoreactivity in the gastric mucosa. Pretreatment with Lawesson's reagent (27 µmol/kg) attenuated ALD-mediated gastric damage (15.77±5.3 mm2); reduced TNF-α, IL-1β, and MDA formation (1502±150.2 pg/mL, 632.3±43.4 pg/mL, 78.4±7.6 nmol/g, respectively); lowered MPO activity (11.7±2.8 U/mg); and increased the level of GSH in the gastric tissue (397.9±40.2 µg/g). Glibenclamide alone reversed the gastric protective effect of Lawesson's reagent. However, glibenclamide plus diazoxide did not alter the effects of Lawesson's reagent. Our results suggest that Lawesson's reagent plays a protective role against ALD-induced gastric damage through mechanisms that depend at least in part on activation of ATP-sensitive potassium (KATP) channels.


Asunto(s)
Animales , Femenino , Ratas , Alendronato/antagonistas & inhibidores , Mucosa Gástrica/efectos de los fármacos , Sulfuro de Hidrógeno/farmacología , Indicadores y Reactivos/farmacología , Compuestos Organotiofosforados/farmacología , Gastropatías/inducido químicamente , Análisis de Varianza , Cistationina gamma-Liasa/análisis , Diagnóstico por Computador , Diazóxido/administración & dosificación , Mucosa Gástrica/patología , Glutatión/análisis , Gliburida/administración & dosificación , Interleucina-1beta/análisis , Canales KATP/farmacología , Malondialdehído/análisis , Peroxidasa/análisis , Peroxidasa/metabolismo , Ratas Wistar , Gastropatías/enzimología , Gastropatías/patología , Factor de Necrosis Tumoral alfa/análisis
6.
Braz. j. med. biol. res ; 46(8): 681-688, ago. 2013. tab, graf
Artículo en Inglés | LILACS | ID: lil-684528

RESUMEN

Hepatic oval cells (HOCs) are recognized as facultative liver progenitor cells that play a role in liver regeneration after acute liver injury. Here, we investigated the in vitro proliferation and differentiation characteristics of HOCs in order to explore their potential capacity for intrahepatic transplantation. Clusters or scattered HOCs were detected in the portal area and interlobular bile duct in the liver of rats subjected to the modified 2-acetylaminofluorene and partial hepatectomy method. Isolated HOCs were positive for c-kit and CD90 staining (99.8% and 88.8%, respectively), and negative for CD34 staining (3.6%) as shown by immunostaining and flow cytometric analysis. In addition, HOCs could be differentiated into hepatocytes and bile duct epithelial cells after leukemia inhibitory factor deprivation. A two-cuff technique was used for orthotopic liver transplantation, and HOCs were subsequently transplanted into recipients. Biochemical indicators of liver function were assessed 4 weeks after transplantation. HOC transplantation significantly prolonged the median survival time and improved the liver function of rats receiving HOCs compared to controls (P=0.003, Student t-test). Administration of HOCs to rats also receiving liver transplantation significantly reduced acute allograft rejection compared to control liver transplant rats 3 weeks following transplantation (rejection activity index score: control=6.3±0.9; HOC=3.5±1.5; P=0.005). These results indicate that HOCs may be useful in therapeutic liver regeneration after orthotopic liver transplantation.


Asunto(s)
Animales , Femenino , Masculino , Ratas , Proliferación Celular , Diferenciación Celular/fisiología , Trasplante de Células/métodos , Hepatocitos/citología , Trasplante de Hígado/métodos , Citometría de Flujo , Rechazo de Injerto/diagnóstico , Hepatectomía , Inmunohistoquímica , Hígado/anatomía & histología , Hígado/cirugía , Cultivo Primario de Células , Ratas Endogámicas Lew , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Tasa de Supervivencia
7.
Braz. j. med. biol. res ; 46(8): 676-680, ago. 2013. graf
Artículo en Inglés | LILACS | ID: lil-684529

RESUMEN

Multipotent mesenchymal stromal cells (MSCs) were first isolated from bone marrow and then from various adult tissues including placenta, cord blood, deciduous teeth, and amniotic fluid. MSCs are defined or characterized by their ability to adhere to plastic, to express specific surface antigens, and to differentiate into osteogenic, chondrogenic, adipogenic, and myogenic lineages. Although the molecular mechanisms that control MSC proliferation and differentiation are not well understood, the involvement of microRNAs has been reported. In the present study, we investigated the role of miR-125b during osteoblastic differentiation in humans. We found that miR-125b increased during osteoblastic differentiation, as well as Runx2 and ALPL genes. To study whether the gain or loss of miR-125b function influenced osteoblastic differentiation, we transfected MSCs with pre-miR-125b or anti-miR-125b and cultured the transfected cells in an osteoblastic differentiation medium. After transfection, no change was observed in osteoblastic differentiation, and Runx2, OPN, and ALPL gene expression were not changed. These results suggest that the gain or loss of miR-125b function does not influence levels of Runx2, OPN, and ALPL during osteoblastic differentiation.


Asunto(s)
Femenino , Humanos , Masculino , Fosfatasa Alcalina/metabolismo , Diferenciación Celular/fisiología , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , MicroARNs/metabolismo , Osteoblastos/citología , Osteopontina/metabolismo , Fosfatasa Alcalina/genética , Antígenos de Diferenciación/aislamiento & purificación , Células de la Médula Ósea/citología , Subunidad alfa 1 del Factor de Unión al Sitio Principal/genética , Expresión Génica/fisiología , Leucocitos Mononucleares/citología , Células Madre Mesenquimatosas/citología , MicroARNs/genética , Osteoblastos/metabolismo , Osteogénesis/fisiología , Osteopontina/genética , Cultivo Primario de Células , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transfección
8.
Braz. j. med. biol. res ; 46(8): 689-695, ago. 2013. tab, graf
Artículo en Inglés | LILACS | ID: lil-684530

RESUMEN

Some clinical isolates of Pseudomonas aeruginosa stored in our culture collection did not grow or grew poorly and showed lysis on the culture plates when removed from the collection and inoculated on MacConkey agar. One hypothesis was that bacteriophages had infected and killed those clinical isolates. To check the best storage conditions to maintain viable P. aeruginosa for a longer time, clinical isolates were stored at various temperatures and were grown monthly. We investigated the presence of phage in 10 clinical isolates of P. aeruginosa stored in our culture collection. Four strains of P. aeruginosa were infected by phages that were characterized by electron microscopy and isolated to assess their ability to infect. The best condition to maintain the viability of the strains during storage was in water at room temperature. Three Siphoviridae and two Myoviridae phages were visualized and characterized by morphology. We confirmed the presence of bacteriophages infecting clinical isolates, and their ability to infect and lyse alternative hosts. Strain PAO1, however, did not show lysis to any phage. Mucoid and multidrug resistant strains of P. aeruginosa showed lysis to 50% of the phages tested.


Asunto(s)
Humanos , Bacteriólisis/fisiología , Bacteriófagos/aislamiento & purificación , Pseudomonas aeruginosa/virología , Técnicas Bacteriológicas , Bancos de Muestras Biológicas , Bacteriófagos/ultraestructura , Medios de Cultivo , Farmacorresistencia Bacteriana Múltiple , Microscopía Electrónica , Myoviridae/aislamiento & purificación , Pseudomonas aeruginosa/clasificación , Pseudomonas aeruginosa/aislamiento & purificación , Siphoviridae/aislamiento & purificación , Ensayo de Placa Viral , Virulencia
9.
Braz. j. med. biol. res ; 46(8): 670-675, ago. 2013. tab, graf
Artículo en Inglés | LILACS | ID: lil-684531

RESUMEN

Ziyuglycoside II is an active compound of Sanguisorba officinalis L. that has anti-inflammation, antioxidation, antibiosis, and homeostasis properties. We report here on the anticancer effect of ziyuglycoside II on human gastric carcinoma BGC-823 cells. We investigated the effects of ziyuglycoside II on cell growth, cell cycle, and cell apoptosis of this cell line. Our results revealed that ziyuglycoside II could inhibit the proliferation of BGC-823 cells by inducing apoptosis but not cell cycle arrest, which was associated with regulation of Bax/Bcl-2 expression, and activation of the caspase-3 pathway. Our study is the first to report the antitumor potential of ziyuglycoside II in BGC-823 gastric cancer cells. Ziyuglycoside II may become a potential therapeutic agent against gastric cancer in the future.


Asunto(s)
Humanos , Apoptosis/efectos de los fármacos , /metabolismo , /metabolismo , Saponinas/farmacología , Transducción de Señal/efectos de los fármacos , /metabolismo , Antineoplásicos/farmacología , Línea Celular Tumoral , Carcinoma/tratamiento farmacológico , /efectos de los fármacos , Inhibidores de Caspasas/metabolismo , Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Fluorometría , Fluorouracilo/farmacología , /efectos de los fármacos , Sanguisorba/química , Neoplasias Gástricas/tratamiento farmacológico , /efectos de los fármacos
10.
Braz. j. med. biol. res ; 46(8): 700-707, ago. 2013. tab, graf
Artículo en Inglés | LILACS | ID: lil-684532

RESUMEN

Follicle cultures reproduce in vitro the functional features observed in vivo. In a search for an ideal model, we cultured bovine antral follicle wall sections (FWS) in a serum-free defined medium (DM) known to induce 17β-estradiol (E2) production, and in a nondefined medium (NDM) containing serum. Follicles were sectioned and cultured in NDM or DM for 24 or 48 h. Morphological features were determined by light microscopy. Gene expression of steroidogenic enzymes and follicle-stimulating hormone (FSH) receptor were determined by RT-PCR; progesterone (P4) and E2 concentrations in the media were measured by radioimmunoassay. DM, but not NDM, maintained an FWS morphology in vitro that was similar to fresh tissue. DM also induced an increase in the expression of all steroidogenic enzymes, except FSH receptor, but NDM did not. In both DM and NDM, there was a gradual increase in P4 throughout the culture period; however, P4 concentration was significantly higher in NDM. In both media, E2 concentration was increased at 24 h, followed by a decrease at 48 h. The E2:P4 ratio was higher in DM than in NDM. These results suggest that DM maintains morphological structure, upregulates the expression of steroidogenic enzyme genes, and maintains steroid production with a high E2:P4 ratio in FWS cultures.


Asunto(s)
Animales , Bovinos , Femenino , Medios de Cultivo/farmacología , Estradiol/farmacología , Folículo Ovárico/efectos de los fármacos , Progesterona/farmacología , Técnicas de Cultivo de Tejidos , Análisis de Varianza , Aromatasa/genética , Medio de Cultivo Libre de Suero , Enzima de Desdoblamiento de la Cadena Lateral del Colesterol/genética , Expresión Génica , Folículo Ovárico/anatomía & histología , Fosfoproteínas/genética , Progesterona Reductasa/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Receptores de HFE/genética , /genética
11.
Braz. j. med. biol. res ; 46(8): 715-721, ago. 2013. tab, graf
Artículo en Inglés | LILACS | ID: lil-684533

RESUMEN

Immobilization, used in clinical practice to treat traumatologic problems, causes changes in muscle, but it is not known whether changes also occur in nerves. We investigated the effects of immobilization on excitability and compound action potential (CAP) and the ultrastructure of the rat sciatic nerve. Fourteen days after immobilization of the right leg of adult male Wistar rats (n=34), animals were killed and the right sciatic nerve was dissected and mounted in a moist chamber. Nerves were stimulated at a baseline frequency of 0.2 Hz and tested for 2 min at 20, 50, and 100 Hz. Immobilization altered nerve excitability. Rheobase and chronaxy changed from 3.13±0.05 V and 52.31±1.95 µs (control group, n=13) to 2.84±0.06 V and 59.71±2.79 µs (immobilized group, n=15), respectively. Immobilization altered the amplitude of CAP waves and decreased the conduction velocity of the first CAP wave (from 93.63±7.49 to 79.14±5.59 m/s) but not of the second wave. Transmission electron microscopy showed fragmentation of the myelin sheath of the sciatic nerve of immobilized limbs and degeneration of the axon. In conclusion, we demonstrated that long-lasting leg immobilization can induce alterations in nerve function.


Asunto(s)
Animales , Masculino , Potenciales de Acción/fisiología , Miembro Posterior/inervación , Inmovilización/efectos adversos , Degeneración Nerviosa/fisiopatología , Nervio Ciático/fisiopatología , Cronaxia/fisiología , Microscopía Electrónica de Transmisión , Vaina de Mielina/fisiología , Ratas Wistar , Factores de Tiempo
12.
Braz. j. med. biol. res ; 46(8): 696-699, ago. 2013. graf
Artículo en Inglés | LILACS | ID: lil-684534

RESUMEN

We investigated the effect of fish oil (FO) supplementation on tumor growth, cyclooxygenase 2 (COX-2), peroxisome proliferator-activated receptor gamma (PPARγ), and RelA gene and protein expression in Walker 256 tumor-bearing rats. Male Wistar rats (70 days old) were fed with regular chow (group W) or chow supplemented with 1 g/kg body weight FO daily (group WFO) until they reached 100 days of age. Both groups were then inoculated with a suspension of Walker 256 ascitic tumor cells (3×107 cells/mL). After 14 days the rats were killed, total RNA was isolated from the tumor tissue, and relative mRNA expression was measured using the 2-ΔΔCT method. FO significantly decreased tumor growth (W=13.18±1.58 vs WFO=5.40±0.88 g, P<0.05). FO supplementation also resulted in a significant decrease in COX-2 (W=100.1±1.62 vs WFO=59.39±5.53, P<0.001) and PPARγ (W=100.4±1.04 vs WFO=88.22±1.46, P<0.05) protein expression. Relative mRNA expression was W=1.06±0.022 vs WFO=0.31±0.04 (P<0.001) for COX-2, W=1.08±0.02 vs WFO=0.52±0.08 (P<0.001) for PPARγ, and W=1.04±0.02 vs WFO=0.82±0.04 (P<0.05) for RelA. FO reduced tumor growth by attenuating inflammatory gene expression associated with carcinogenesis.


Asunto(s)
Animales , Masculino , /genética , Proliferación Celular/efectos de los fármacos , /genética , Aceites de Pescado/farmacología , PPAR gamma/genética , Factor de Transcripción ReIA/genética , /metabolismo , Suplementos Dietéticos , Ácidos Docosahexaenoicos/farmacología , Ácido Eicosapentaenoico/farmacología , Aceites de Pescado/química , Inhibidores de Crecimiento/farmacología , Immunoblotting , Ratas Wistar , Reacción en Cadena en Tiempo Real de la Polimerasa , Transcripción Genética/efectos de los fármacos
13.
Braz. j. med. biol. res ; 46(7): 580-588, ago. 2013. graf
Artículo en Inglés | LILACS | ID: lil-682394

RESUMEN

Sublethal ischemic preconditioning (IPC) is a powerful inducer of ischemic brain tolerance. However, its underlying mechanisms are still not well understood. In this study, we chose four different IPC paradigms, namely 5 min (5 min duration), 5×5 min (5 min duration, 2 episodes, 15-min interval), 5×5×5 min (5 min duration, 3 episodes, 15-min intervals), and 15 min (15 min duration), and demonstrated that three episodes of 5 min IPC activated autophagy to the greatest extent 24 h after IPC, as evidenced by Beclin expression and LC3-I/II conversion. Autophagic activation was mediated by the tuberous sclerosis type 1 (TSC1)-mTor signal pathway as IPC increased TSC1 but decreased mTor phosphorylation. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and hematoxylin and eosin staining confirmed that IPC protected against cerebral ischemic/reperfusion (I/R) injury. Critically, 3-methyladenine, an inhibitor of autophagy, abolished the neuroprotection of IPC and, by contrast, rapamycin, an autophagy inducer, potentiated it. Cleaved caspase-3 expression, neurological scores, and infarct volume in different groups further confirmed the protection of IPC against I/R injury. Taken together, our data indicate that autophagy activation might underlie the protection of IPC against ischemic injury by inhibiting apoptosis.


Asunto(s)
Animales , Masculino , Ratas , Apoptosis/fisiología , Autofagia/fisiología , Isquemia Encefálica/fisiopatología , Precondicionamiento Isquémico/métodos , Degeneración Nerviosa/prevención & control , Daño por Reperfusión/metabolismo , Adenina/análogos & derivados , Adenina/farmacología , Isquemia Encefálica/prevención & control , /metabolismo , Cerebro/lesiones , Etiquetado Corte-Fin in Situ , Inmunosupresores/farmacología , Ratas Sprague-Dawley , Sirolimus/farmacología , Factores de Tiempo , Serina-Treonina Quinasas TOR/metabolismo , Proteínas Supresoras de Tumor/metabolismo
14.
Braz. j. med. biol. res ; 46(7): 601-606, ago. 2013. graf
Artículo en Inglés | LILACS | ID: lil-682395

RESUMEN

Interleukin (IL)-33, the most recent member of the IL family of cytokines, signals through the ST2 receptor. IL-33/ST2 signaling mediates antigen challenge-induced mechanical hyperalgesia in the joints and cutaneous tissues of immunized mice. The present study asked whether IL-33/ST2 signaling is relevant to overt pain-like behaviors in mice. Acetic acid and phenyl-p-benzoquinone induced significant writhing responses in wild-type (WT) mice; this overt nociceptive behavior was reduced in ST2-deficient mice. In an antigen-challenge model, ST2-deficient immunized mice had reduced induced flinch and licking overt pain-like behaviors. In the formalin test, ST2-deficient mice also presented reduced flinch and licking responses, compared with WT mice. Naive WT and ST2-deficient mice presented similar responses in the rota-rod, hot plate, and electronic von Frey tests, indicating no impairment of motor function or alteration in basal nociceptive responses. The results demonstrate that IL-33/ST2 signaling is important in the development of overt pain-like behaviors.


Asunto(s)
Animales , Ratones , Hiperalgesia/metabolismo , Interleucinas/metabolismo , Dolor Nociceptivo/fisiopatología , Dimensión del Dolor/métodos , Receptores de Interleucina/deficiencia , Transducción de Señal , Ácido Acético , Benzoquinonas , Homocigoto , Calor , Ratones Endogámicos BALB C , Actividad Motora/fisiología , Nocicepción/fisiología , Dolor Nociceptivo/inducido químicamente , Ovalbúmina/inmunología , Prueba de Desempeño de Rotación con Aceleración Constante
15.
Braz. j. med. biol. res ; 46(7): 559-566, ago. 2013. graf
Artículo en Inglés | LILACS | ID: lil-682396

RESUMEN

Hepatic progenitor cells (HPCs) are a potential cell source for liver cell transplantation but do not function like mature liver cells. We sought an effective and reliable method to induce HPC maturation. An immortalized HP14.5 albumin promoter-driven Gaussian luciferase (ALB-GLuc) cell line was established from HPCs isolated from fetal mouse liver of post coitus day 14.5 mice to investigate the effect of induction factors on ALB promoter. HP14.5 parental cells were cultured in DMEM with different combinations of 2% horse serum (HS), 0.1 µM dexamethasone (DEX), 10 ng/mL hepatic growth factor (HGF), and/or 20 ng/mL fibroblast growth factor 4 (FGF4). Trypan blue and crystal violet staining were used to assess cell proliferation with different induction conditions. Expression of hepatic markers was measured by semi-quantitative RT-PCR, Western blot, and immunofluorescence. Glycogen storage and metabolism were detected by periodic acid-Schiff and indocyanine green (ICG) staining. GLuc activity indicated ALB expression. The combination of 2% HS+0.1 µM Dex+10 ng/mL HGF+20 ng/mL FGF4 induced the highest ALB-GLuc activity. Cell proliferation decreased in 2% HS but increased by adding FGF4. Upon induction, and consistent with hepatocyte development, DLK, AFP, and CK19 expression decreased, while ALB, CK18, and UGT1A expression increased. The maturity markers tyrosine aminotransferase and apolipoprotein B were detected at days 3 and 6 post-induction, respectively. ICG uptake and glycogen synthesis were detectable at day 6 and increased over time. Therefore, we demonstrated that HPCs were induced to differentiate into functional mature hepatocytes in vitro, suggesting that factor-treated HPCs may be further explored as a means of liver cell transplantation.


Asunto(s)
Animales , Ratones , Diferenciación Celular/efectos de los fármacos , Embrión de Mamíferos/efectos de los fármacos , Hepatocitos/citología , Hígado/citología , Células Madre/efectos de los fármacos , Antígenos de Diferenciación/análisis , Apolipoproteínas B/aislamiento & purificación , Proliferación Celular , Dexametasona/administración & dosificación , Factores de Crecimiento de Fibroblastos/administración & dosificación , Violeta de Genciana , Glucógeno/metabolismo , Factor de Crecimiento de Hepatocito/administración & dosificación , Verde de Indocianina/farmacocinética , Cultivo Primario de Células/métodos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Madre/citología , Azul de Tripano , Tirosina Transaminasa/aislamiento & purificación
16.
Braz. j. med. biol. res ; 46(7): 623-628, ago. 2013. tab, graf
Artículo en Inglés | LILACS | ID: lil-682397

RESUMEN

Recent animal studies have indicated that overexpression of the elongation of long-chain fatty acids family member 6 (Elovl6) gene can cause insulin resistance and β-cell dysfunction. These are the major factors involved in the development of type 2 diabetes mellitus (T2DM). To identify the relationship between single nucleotide polymorphisms (SNP) of ELOVL6 and T2DM pathogenesis, we conducted a case-control study of 610 Han Chinese individuals (328 newly diagnosed T2DM and 282 healthy subjects). Insulin resistance and islet first-phase secretion function were evaluated by assessment of insulin resistance in a homeostasis model (HOMA-IR) and an arginine stimulation test. Three SNPs of the ELOVL6 gene were genotyped with polymerase chain reaction-restriction fragment length polymorphism, with DNA sequencing used to confirm the results. Only genotypes TT and CT of the ELOVL6 SNP rs12504538 were detected in the samples. Genotype CC was not observed. The T2DM group had a higher frequency of the C allele and the CT genotype than the control group. Subjects with the CT genotype had higher HOMA-IR values than those with the TT genotype. In addition, no statistical significance was observed between the genotype and allele frequencies of the control and T2DM groups for SNPs rs17041272 and rs6824447. The study indicated that the ELOVL6 gene polymorphism rs12504538 is associated with an increased risk of T2DM, because it causes an increase in insulin resistance.


Asunto(s)
Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Acetiltransferasas/genética , /genética , Polimorfismo de Nucleótido Simple/genética , China/etnología , /etnología , Genotipo , Resistencia a la Insulina/genética , Células Secretoras de Insulina/patología , Polimorfismo de Longitud del Fragmento de Restricción
17.
Braz. j. med. biol. res ; 46(7): 574-579, ago. 2013. tab, graf
Artículo en Inglés | LILACS | ID: lil-682398

RESUMEN

Vascular hyporeactivity is an important factor in irreversible shock, and post-shock mesenteric lymph (PSML) blockade improves vascular reactivity after hemorrhagic shock. This study explored the possible involvement of myosin light chain kinase (MLCK) in PSML-mediated vascular hyporeactivity and calcium desensitization. Rats were divided into sham (n=12), shock (n=18), and shock+drainage (n=18) groups. A hemorrhagic shock model (40±2 mmHg, 3 h) was established in the shock and shock+drainage groups. PSML drainage was performed from 1 to 3 h from start of hypotension in shock+drainage rats. Levels of phospho-MLCK (p-MLCK) were determined in superior mesenteric artery (SMA) tissue, and the vascular reactivity to norepinephrine (NE) and sensitivity to Ca2+ were observed in SMA rings in an isolated organ perfusion system. p-MLCK was significantly decreased in the shock group compared with the sham group, but increased in the shock+drainage group compared with the shock group. Substance P (1 nM), an agonist of MLCK, significantly elevated the decreased contractile response of SMA rings to both NE and Ca2+ at various concentrations. Maximum contractility (Emax) in the shock group increased with NE (from 0.179±0.038 to 0.440±0.177 g/mg, P<0.05) and Ca2+ (from 0.515±0.043 to 0.646±0.096 g/mg, P<0.05). ML-7 (0.1 nM), an inhibitor of MLCK, reduced the increased vascular response to NE and Ca2+ at various concentrations in the shock+drainage group (from 0.744±0.187 to 0.570±0.143 g/mg in Emax for NE and from 0.729±0.037 to 0.645±0.056 g/mg in Emax for Ca2+, P<0.05). We conclude that MLCK is an important contributor to PSML drainage, enhancing vascular reactivity and calcium sensitivity in rats with hemorrhagic shock.


Asunto(s)
Animales , Masculino , Calcio/metabolismo , Linfa/fisiología , Arteria Mesentérica Superior/fisiopatología , Músculo Liso Vascular/fisiopatología , Quinasa de Cadena Ligera de Miosina/fisiología , Choque Hemorrágico/fisiopatología , Contracción Muscular , Arteria Mesentérica Superior/metabolismo , Músculo Liso Vascular/metabolismo , Cadenas Ligeras de Miosina/metabolismo , Quinasa de Cadena Ligera de Miosina/análisis , Distribución Aleatoria , Ratas Wistar , Choque Hemorrágico/enzimología
18.
Braz. j. med. biol. res ; 46(7): 607-613, ago. 2013. tab, graf
Artículo en Inglés | LILACS | ID: lil-682399

RESUMEN

Recent evidence shows that moxifloxacin could exert an antimicrobial effect against Helicobacter pylori in both in vitro and in vivo models. To systematically evaluate whether moxifloxacin-containing triple therapy could improve eradication rates and reduce side effects in first-line or second-line anti-H. pylori treatment, eligible articles were identified by searches of electronic databases. We included all randomized trials comparing moxifloxacin-based triple therapy with standard triple or quadruple therapy during H. pylori eradication treatment. Statistical analysis was performed with Review Manager 5.0.10. Subanalysis/sensitivity analysis was also performed. We identified seven randomized trials (n=1263). Pooled H. pylori eradication rates were 79.03% (95%CI: 75.73-82.07) and 68.33% (95%CI: 64.44-72.04) for patients with moxifloxacin-based triple therapy or with standard triple or quadruple therapy, respectively (intention-to-treat analysis). The odds ratio (OR) was 1.82 (95%CI: 1.17-2.81), the occurrence of total side effects was 15.23% (95%CI: 12.58-18.20) and 27.17% (95%CI: 23.64-30.92) for groups with or without moxifloxacin, and the summary OR was 0.45 (95%CI: 0.26-0.77). In subgroup analyses, we noted that the second-line eradication rate in the moxifloxacin group was significantly higher than that in the quadruple therapy group (73.33 vs 60.17%, OR: 1.78, 95%CI: 1.16-2.73, P<0.001). However, there was no difference in first-line eradication treatment. Findings from this meta-analysis suggest that moxifloxacin-based triple therapy is more effective and better tolerated than standard triple or quadruple therapy. Therefore, a moxifloxacin-based triple regimen should be used in the second-line treatment of H. pylori infection.


Asunto(s)
Humanos , Antibacterianos/uso terapéutico , Fluoroquinolonas/uso terapéutico , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori/efectos de los fármacos , Antibacterianos/efectos adversos , Quimioterapia Combinada/métodos , Fluoroquinolonas/efectos adversos , Ensayos Clínicos Controlados Aleatorios como Asunto
19.
Braz. j. med. biol. res ; 46(7): 614-622, ago. 2013. tab
Artículo en Inglés | LILACS | ID: lil-682400

RESUMEN

The objective of this study was to examine hepatitis B virus (HBV) subgenotypes and mutations in enhancer II, basal core promoter, and precore regions of HBV in relation to risks of liver cirrhosis (LC) and hepatocellular carcinoma (HCC) in Southeast China. A case-control study was performed, including chronic hepatitis B (CHB; n=125), LC (n=120), and HCC (n=136). HBV was genotyped by multiplex polymerase chain reaction and subgenotyped by restriction fragment length polymorphism. HBV mutations were measured by DNA sequencing. HBV genotype C (68.2%) predominated and genotype B (30.2%) was the second most common. Of these, C2 (67.5%) was the most prevalent subgenotype, and B2 (30.2%) ranked second. Thirteen mutations with a frequency >5% were detected. Seven mutation patterns (C1653T, G1719T, G1730C, T1753C, A1762T, G1764A, and G1799C) were associated with C2, and four patterns (C1810T, A1846T, G1862T, and G1896A) were associated with B2. Six patterns (C1653T, G1730C, T1753C, A1762T, G1764A, and G1799C) were obviously associated with LC, and 10 patterns (C1653T, G1730C, T1753C, A1762T, G1764A, G1799C, C1810T, A1846T, G1862T, and G1896A) were significantly associated with HCC compared with CHB. Four patterns (C1810T, A1846T, G1862T, and G1896A) were significantly associated with HCC compared with LC. Multivariate regression analyses showed that HBV subgenotype C2 and C2-associated mutation patterns (C1653T, T1753C, A1762T, and G1764A) were independent risk factors for LC when CHB was the control, and that B2-associated mutation patterns (C1810T, A1846T, G1862T, and G1896A) were independent risk factors for HCC when LC was the control.


Asunto(s)
Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Carcinoma Hepatocelular/virología , Genotipo , Virus de la Hepatitis B/genética , Cirrosis Hepática/virología , Neoplasias Hepáticas/virología , Mutación/genética , Alanina Transaminasa/sangre , Bilirrubina/sangre , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , China , Antígenos del Núcleo de la Hepatitis B/genética , Virus de la Hepatitis B/clasificación , Reacción en Cadena de la Polimerasa Multiplex , Polimorfismo de Longitud del Fragmento de Restricción , Factores de Riesgo , Albúmina Sérica/análisis
20.
Braz. j. med. biol. res ; 46(7): 589-600, ago. 2013. graf
Artículo en Inglés | LILACS | ID: lil-682401

RESUMEN

We investigated the GABA-induced inactivation of V2 neurons and terminals on the receptive field properties of this area in an anesthetized and paralyzed Cebus apella monkey. Extracellular single-unit activity was recorded using tungsten microelectrodes in a monkey before and after pressure-injection of a 0.25 or 0.5 M GABA solution. The visual stimulus consisted of a bar moving in 8 possible directions. In total, 24 V2 neurons were studied before and after blocker injections in 4 experimental sessions following GABA injection into area V2. A group of 10 neurons were studied over a short period. An additional 6 neurons were investigated over a long period after the GABA injection. A third group of 8 neurons were studied over a very long period. Overall, these 24 neurons displayed an early (1-20 min) significant general decrease in excitability with concomitant changes in orientation or direction selectivity. GABA inactivation in area V2 produced robust inhibition in 80% and a significant change in directional selectivity in 60% of the neurons examined. These GABA projections are capable of modulating not only levels of spontaneous and driven activity of V2 neurons but also receptive field properties such as direction selectivity.


Asunto(s)
Animales , Masculino , GABAérgicos/farmacología , Inhibición Neural , Neuronas/efectos de los fármacos , Orientación/efectos de los fármacos , Corteza Visual/efectos de los fármacos , Ácido gamma-Aminobutírico/farmacología , Cebus , Electrocardiografía , Lidocaína/metabolismo , Microelectrodos , Inhibición Neural/efectos de los fármacos , Estimulación Luminosa , Factores de Tiempo , Ácido gamma-Aminobutírico/fisiología
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