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1.
Gastroenterol. hepatol. (Ed. impr.) ; 47(4): 352-365, Abr. 2024. tab, graf
Artigo em Inglês | IBECS | ID: ibc-231802

RESUMO

Background: The leucine-rich repeat-containing G-protein-coupled receptor 4 (LGR4) plays an important role in stem cell differentiation, organ development and cancer. Whether LGR4 affects the progression of hepatocellular carcinoma (HCC) remains unknown. This study aimed to reveal the role of LGR4 in HCC. Methods: Clinical samples of HCC were collected to assess the expression of LGR4 and its correlation with patients’ clinical characteristics. The expression level of LGR4 in HCC cells was altered by pharmacological and genetic methods, and the role of LGR4 in HCC progression was analyzed by in vivo and in vitro assays. HCC was induced by diethylnitrosamine (DEN) and carbon tetrachloride (CCl4) in wild-type and LGR4 deficient mice, the effect of LGR4 on HCC was examined by histopathological evaluation and biochemical assays. Results: LGR4 expression was up-regulated in HCC samples, and its expression level was positively correlated with tumor size, microvascular invasion (MVI), TNM stage and pathological differentiation grade of HCC patients. In the mouse HCC model induced by DEN+CCl4, knockdown of LGR4 effectively inhibited the progression of HCC. Silencing of LGR4 inhibited the proliferation, migration, invasion, stem cell-like properties and Warburg effect of HCC cells. These phenotypes were promoted by R-spondin2 (Rspo2), an endogenous ligand for LGR4. Rspo2 markedly increased the nuclear translocation of β-catenin, whereas IWR-1, an inhibitor of Wnt/β-catenin signaling, reversed its effect. Deficiency of LGR4 significantly reduced the nuclear translocation of β-catenin and the expression of its downstream target genes cyclinD1 and c-Myc. Conclusions: LGR4 promotes HCC progression via Wnt/β-catenin signaling pathway. (AU)


Antecedentes: El receptor de acoplamiento de proteínas G de secuencia repetida 4 (LGR4), rico en leucina, juega un papel importante en la diferenciación de células madre, el desarrollo de órganos y el cáncer. Se desconoce si LGR4 afecta la progresión del carcinoma hepatocelular (HCC). El objetivo de este estudio es revelar el papel de LGR4 en el HCC. Métodos: Se recolectaron muestras clínicas de HCC para evaluar la expresión de LGR4 y su correlación con los resultados clínicos de HCC. Alterar los niveles de expresión de LGR4 en las células de HCC mediante métodos farmacológicos y genéticos y analizar el papel de LGR4 en la progresión del cáncer de hígado mediante mediciones in vivo e in vitro. El HCC fue inducido en ratones de tipo salvaje y con defectos de LGR4 con Nitrosamina de dietilo (DEN) y cloruro de carbono (CCl4), y los efectos de LGR4 sobre el HCC fueron detectados por evaluación histopatológica y determinación bioquímica. Resultados: La expresión de LGR4 está regulada en HCC, y su nivel de expresión está positivamente relacionado con el tamaño tumoral, la infiltración microvascular (MVI), la etapa de TNM y el grado de diferenciación patológica en pacientes con HCC. En el modelo de HCC de ratón inducido por DEN+CCl4, golpear bajo LGR4 inhibió efectivamente la progresión del HCC. El silencio de LGR4 inhibe la proliferación, migración, invasión, propiedades similares a las células madre y el efecto Warburg de las células HCC. Estos fenotipos son promovidos por el ligando endógeno roof slab-specific sponge 2 (Rspo2)de LGR4. El Rspo2 aumentó significativamente la translocación nuclear de la proteína beta-catenina, mientras que el inhibidor de la señalización Wnt/beta-cateninaIWR-1 revirtió su acción... (AU)


Assuntos
Leucina , Células-Tronco , Neoplasias , Carcinoma Hepatocelular
2.
Int. microbiol ; 26(1): 11-24, Ene. 2023. ilus
Artigo em Inglês | IBECS | ID: ibc-215913

RESUMO

The NADPH-regeneration enzymes in Corynebacterium glutamicum were inactivated to construct an NADPH-auxotrophic C. glutamicum strain by gene knockout and gene replacement. The resultant NADPH-auxotrophic C. glutamicum XL-1 ΔZMICg::ISm (i.e., strain Leu-1) grew well in the basic medium only with gluconate as carbon source. Replacement of the native glyceraldehyde 3-phosphate dehydrogenase (NAD-GapDHCg) by NADP-GapDHCa from Clostridium acetobutylicum is an effective strategy for producing L-leucine in NADPH-prototrophic strain XL-1 and NADPH-auxotrophic strain Leu-1, whereas the L-leucine yield did not differ significantly between these strains (14.1 ± 1.8 g/L vs 16.2 ± 1.1 g/L). Enhancing the carbon flux in biosynthetic pathway by recombinant expression plasmid pEC-ABNCE promoted L-leucine production, but the shortage NADPH supply limited the L-leucine yield. The mutated promoters of zwf and icdCg were introduced into C. glutamicum with NADP-GapDHCa and pEC-ABNCE increased L-leucine yield (54.3 ± 2.9 g/L) and improved cell growth (OD562 = 83.4 ± 7.5) in fed-batch fermentation because the resultant strain C. glutamicum XL-1 ΔMICg::ISm GCg::GCa Pzwf-D1 Picd-D2/pEC-ABNCE (i.e., strain Leu-9) exhibited the proper intracellular NADPH and NADH level. This is the first report of constructing an L-leucine high-yielding strain that reasonably supplies NADPH by optimizing the biosynthetic pathway of NADPH from an NADPH-auxotrophic strain.(AU)


Assuntos
Humanos , NADP , Corynebacterium glutamicum , Leucina , Crescimento Celular , Vias Biossintéticas , Microbiologia
3.
Gastroenterol. hepatol. (Ed. impr.) ; 45(5): 342-349, May. 2022. tab, graf
Artigo em Inglês | IBECS | ID: ibc-204300

RESUMO

Background and objective: The emergence of highly tolerable, effective, and shorter duration direct-acting antivirals (DAAs) regimens offers the opportunity to simplify hepatitis C virus management but medical costs are unknown. Thus, we aimed to determine the direct medical costs associated with a combo-simplified strategy (one-step diagnosis and low monitoring) to manage HCV infection within an 8-week glecaprevir/pibrentasvir (GLE/PIB) regimen in clinical practice in Spain. Patients and methods: Healthcare resources and clinical data were collected retrospectively from medical charts of 101 eligible patients at 11 hospitals. Participants were adult, treatment naïve subjects with HCV infection without cirrhosis in whom a combo-simplified strategy with GLE/PIB for 8 weeks were programmed between Apr-2018 and Nov-2018. Results: The GLE/PIB effectiveness was 100% (CI95%: 96.2–100%) in the mITT population and 94.1% (CI95%: 87.5–97.8%) in the ITT population. Three subjects discontinued the combo-simplified strategy prematurely, none of them due to safety reasons. Five subjects reported 8 adverse events, all of mild-moderate intensity. Combo-simplified strategy mean direct costs were 754.35±103.60€ compared to 1689.42€ and 2007.89€ of a theoretical 12-week treatment with 4 or 5 monitoring visits, respectively; and 1370.95€ and 1689.42€ of a theoretical 8-week with 3 or 4 monitoring visits, respectively. Only 4.9% of the subjects used unexpected health care resources. Conclusions: 8-week treatment with GLE/PIB combined with a combo simplified strategy in real-life offers substantial cost savings without affecting the effectiveness and safety compared to traditional approaches.(AU)


Antecedentes y objetivo: La aparición de regímenes antivirales de acción directa altamente tolerables, eficaces y de corta duración permite simplificar el manejo de la hepatitis C, pero los costes médicos se desconocen. Así, se pretende determinar los costes médicos directos asociados a una estrategia simplificada (diagnóstico en un solo paso y monitorización reducida) para controlar la infección por VHC con un régimen de 8 semanas de glecaprevir/pibrentasvir (GLE/PIB) en la práctica clínica en España. Pacientes y métodos: Los recursos sanitarios y los datos clínicos se recopilaron retrospectivamente de las historias médicas de 101 pacientes elegibles en 11 hospitales. Los participantes fueron sujetos adultos, sin tratamiento previo de la infección por VHC y sin cirrosis, en los que se programó una estrategia combinada simplificada con GLE/PIB durante 8 semanas entre abril y noviembre de 2018. Resultados: La eficacia de GLE/PIB fue del 100% (IC 95% 96,2-100) en la población mITT y del 94,1% (IC 95% 87,5-97,8) en la población ITT. Tres sujetos suspendieron prematuramente la estrategia combinada simplificada, ninguno de ellos por razones de seguridad. Cinco sujetos reportaron 8 acontecimientos adversos de intensidad leve-moderada. Los costes directos fueron de 754,35±103,60€ frente a 1.689,42€ y 2.007,89€ de un tratamiento teórico de 12 semanas con 4 o 5 visitas de monitorización, respectivamente; y 1.370,95€ y 1.689,42€ de un tratamiento teórico de 8 semanas con 3 o 4 visitas de monitorización, respectivamente. El 4,9% de los sujetos utilizaron recursos de atención médica inesperados. Conclusiones: En la vida real, el tratamiento de 8 semanas con GLE/PIB junto con una estrategia simplificada ofrece ahorros sustanciales de costos, sin afectar la eficacia y seguridad, en comparación con abordajes tradicionales.(AU)


Assuntos
Humanos , Adulto , Hepatite C/tratamento farmacológico , Hepatite C Crônica/tratamento farmacológico , Hepacivirus , Lactamas Macrocíclicas , Leucina/análogos & derivados , Gastroenterologia , Estudos Retrospectivos
5.
Nutr. hosp ; 35(1): 237-244, ene.-feb. 2018. tab, graf
Artigo em Inglês | IBECS | ID: ibc-172112

RESUMO

Introduction: 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) lyase deficiency is an autosomal recessive disorder that usually presents in the neonatal period with vomiting, metabolic acidosis, hypoglycemia and absent ketonuria. Few cases are reported in the literature, and optimal dietary management and long term outcome are not fully understood. Case report: We report a 2 year old girl with HMG-CoA-lyase deficiency who had limited fasting tolerance on a low protein diet, with several recurrent hospital admissions with severe hypoketotic hypoglycaemia and metabolic acidosis. We also review the dietary management and outcome of other reported cases in the literature. Discussion: In order to define optimal dietary treatment, it is important to collect higher numbers of case studies with detailed dietary management, fasting times and outcome (AU)


Introducción: la deficiencia de la 3-hidroxi-3-metilglutaril-CoA (HMG-CoA) liasa es un desorden autosómico recesivo que normalmente se presenta en la infancia con vómitos, acidosis metabólica, hipoglicemia y sin cetonuria. Se han publicado pocos casos en la literatura científica sobre el mejor tratamiento dietético para el adecuado desarrollo de los pacientes a largo plazo, por lo que esta deficiencia no es bien conocida. Caso clínico: presentamos una niña de 2 años con deficiencia de la 3-hidroxi-3-metilglutaril-CoA (HMG-CoA) liasa. Recibiendo una dieta baja en proteína con una tolerancia de ayuno limitada con episodios recurrentes de admisión hospitalaria con hipoglicemia hipoketotica y acidosis metabólica. También hemos revisado el tratamiento dietético y el desarrollo de otros casos publicados en la literatura científica. Discusión: es importante recoger más casos clínicos describiendo el tratamiento dietético seguido, el tiempo máximo de ayuno y el desarrollo de los pacientes con el objetivo de definir el mejor tratamiento (AU)


Assuntos
Humanos , Feminino , Lactente , Hidroximetilglutaril-CoA Sintase/deficiência , Erros Inatos do Metabolismo/dietoterapia , Cetose/dietoterapia , Leucina/efeitos adversos , Gorduras na Dieta/efeitos adversos , Hipoglicemia/dietoterapia
6.
Rev. andal. med. deporte ; 10(3): 137-141, sept. 2017. graf, tab
Artigo em Português | IBECS | ID: ibc-165978

RESUMO

Objetivo. O presente estudo prospectivo, randomizado, duplo‐cego e placebo‐controlado, verificou o efeito da ingestão de 3g/dia‐1 Beta‐hidroxi‐Beta‐metilbutirato sobre os parâmetros da curva força‐tempo em canoístas de elite. Método. Participaram 24 canoístas, homens, de elite, com 21.41±5.35 anos, 173.36±8.27cm e 69.83±10.29kg. Formaram‐se 2 grupos, um suplementado (HMB) e outro placebo (CON), ambos acompanhados por 14 dias e submetidos a teste máximo de 4min (pré e pós) num caiaque ergômetro. Resultados. Apontam melhora na eficiência mecânica em consonância com o aumento significativo do impulso gerado (17.23%, p=0.02), da potência média (26.6%, p=0.01), frequência de remada (13.5%, p=0.04), perante teste máximo de 4min em ergômetro. Conclusão. Houve melhora na capacidade de gerar potência, que pode estar associada com a suplementação de Beta‐hidroxi‐Beta‐metilbutirato, através da diminuição do catabolismo durante o treinamento; contudo, o mecanismo pelo qual isso pode ocorrer ainda é desconhecido (AU)


Objetivo. Este estudio aleatorizado, doble ciego prospectivo, controlado y placebo, tubo como objetivo comprobar el efecto de la ingesta de 3g/día‐1 de Beta‐hidroxi‐Beta‐metilbutirato en los parámetros de la curva fuerza‐tiempo en kayakistas de élite. Método. Veinticuatro kayakistas, hombres, élite con 21.41±5.35 años, 173.36±8.27cm y 69.83±10.29kg. Formado dos grupos, uno suplementado (HMB) y otro placebo (CON), ambos siguieron durante 14 días y sometido a máxima 4min prueba (pre y post) en un ergómetro kayak. Resultados. Se apreció una mejora en la eficiencia mecánica en relación con el aumento significativo del impulso generado (17.23% p=0.02), la potencia media (26.6% p=0.01), frecuencia de carrera (13.5% p=0.04) durante una prueba máxima en ergómetro de 4min. Conclusión. Hubo una mejora en la capacidad para generar energía, que puede estar asociada con la administración de suplementos de Beta‐hidroxi‐Beta‐metilbutirato mediante la reducción de catabolismo durante el entrenamiento, sin embargo, el mecanismo por el que esto puede ocurrir es aún desconocido (AU)


Objective. This prospective, randomized, double‐blind, placebo‐controlled, checked the effect of the intake of 3g/day‐1 of Beta‐Hidroxy‐Beta‐Methylbutyrato on the parameters of the force‐time curve in elite kayakers. Method. 24 paddlers, men, elite with 21.41±5.35 years, 173.36±8.27cm and 69.83±10.29kg. Formed two groups, one supplemented (HMB) and another placebo (CON), both followed for 14 days and subjected to maximum test 4min (pre and post) in a kayak ergometer. Results. Point improvement in mechanical efficiency in line with the significant increase in the generated pulse (17.23% p=0.02), average power (26.6% p=0.01), stroke frequency (13.5% p=0.04) before maximum test 4min ergometer. Conclusion. There was improvement in the ability to generate power, which may be associated with supplementation of Beta‐Hidroxy‐Beta‐Methylbutyrato by reducing catabolism during training, however the mechanism by which this may occur is still unknown (AU)


Assuntos
Humanos , Masculino , Adulto , Desempenho Psicomotor/fisiologia , Esportes , Suplementos Nutricionais , Atletas , Leucina/uso terapêutico , Músculo Esquelético , Estudos Prospectivos , Placebos/análise , Método Duplo-Cego , 28599
7.
Nutr. hosp ; 34(1): 204-215, ene.-feb. 2017. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-161162

RESUMO

Introducción: muy pocos suplementos nutricionales han demostrado científicamente su eficacia como ayuda ergogénica. Esta revisión analizará el monohidrato de creatina (MC), el β-hidroxi-β-metilbutirato (HMB), el bicarbonato sódico (BS), la β-alanina y la cafeína. Objetivos: analizar la eficacia, mecanismos de acción, dosis, efectos adversos y algunos deportes que se pueden beneficiar de su consumo. Métodos: búsqueda en la base de datos PubMed de revisiones bibliográficas de los últimos 15 años y artículos originales de los últimos 5 años de las sustancias estudiadas. Resultados: dosis de MC de 20 g/día durante 4-7 días son eficaces para mejorar la fuerza y la potencia muscular y el rendimiento en sprints cortos y repetidos. El HMB en dosis de 3 g/día durante un mínimo de 2 semanas contribuye al aumento de la masa magra y de la masa libre de grasa. La ingesta de 0,3 g/kg de BS mejora el rendimiento en pruebas de 400-1.500 m de atletismo y en sprints intermitentes. Por su parte, dosis de 80 mg/kg/día de β-alanina durante 4-10 semanas pueden mejorar el rendimiento en ejercicios intermitentes de alta intensidad. Finalmente, la cafeína en dosis de 2 mg/kg mejora la capacidad de reacción y en dosis de 3-6 mg/kg mejora el rendimiento en pruebas de resistencia aeróbica. Conclusiones: los suplementos revisados presentan una demostrada eficacia en el rendimiento físico, pero hay que tener en cuenta que la mayoría de los estudios se han realizado con deportistas de nivel recreativo. Generalmente, la mejora del rendimiento físico con estos suplementos es menor cuanto mejor es el nivel deportivo del individuo; sin embargo, un incremento de apenas un 1% permite a veces avanzar varios puestos en una final. Finalmente, se debe llamar la atención sobre la importancia de optimizar la alimentación antes de plantearse la introducción de suplementos deportivos, especialmente en niños y jóvenes. Las sustancias que hemos analizado poseen una base científica que respalda su efecto ergogénico. Todas ellas se pueden encontrar en el mercado con Certificado de Calidad y Pureza (AU)


Introduction: Very few nutritional supplements have scientifically demonstrated their effectiveness as an ergogenic aid. This review will examine creatine monohydrate (MC), the β-hydroxy-β-methylbutyrate (HMB), sodium bicarbonate (BS), the β-alanine and caffeine. Objectives: To analyze the efficacy, mechanisms of action, dose, side effects and some sports that can benefit from their consumption. Methods: Searching in PubMed bibliographic database reviews from the last 15 years and original articles from the last 5 years of the studied substances. Results: Doses of 20 mg/day for 4-7 days are effective in improving strength and muscular power and performance in short and repeated sprints. HMB at doses of 3 g/day for at least 2 weeks contributes to increased lean mass and fat-free mass. The intake of 0.3 g/kg of BS improves performance on tests of 400-1,500 meters in athletics and intermittent sprints. Meanwhile, doses of 80 mg/kg/day of β-alanine for 4-10 weeks may improve performance in high-intensity intermittent exercise. Finally, caffeine at doses of 2 mg/kg improves responsiveness and 3-6 mg/kg improves performance in endurance tests. Conclusions: The revised supplements have shown their efficacy in physical performance, but it is needed to keep in mind that most studies have been conducted with recreational-level athletes. Generally, the better the individual´s fitness level is the less improvement in physical performance the supplement shows. However, an increase of only 1% may sometimes allow the athlete to advance several positions in a final. Finally, we should draw attention to the importance of optimizing nutrition before considering the introduction of sports supplements, especially in children and youth. All analyzed substances have scientific basis supporting its ergogenic effect. All of them can be found in the market with Certificate of Quality and Purity (AU)


Assuntos
Humanos , Desempenho Atlético/fisiologia , Substâncias para Melhoria do Desempenho/análise , Fenômenos Fisiológicos da Nutrição Esportiva/fisiologia , Creatina/farmacocinética , Cafeína/farmacocinética , Bicarbonato de Sódio/farmacocinética , beta-Alanina/farmacocinética , Leucina/farmacocinética
8.
J. physiol. biochem ; 72(4): 781-789, dic. 2016. tab, graf
Artigo em Inglês | IBECS | ID: ibc-168383

RESUMO

Obesity is a major public health concern and it is essential to identify effective treatments and preventative strategies to stop continued increases in obesity rates. The potential functional roles of the branched chain amino acid leucine make this amino acid an attractive candidate for the treatment and/or prevention of obesity. The objective of this study was to determine if long-term leucine supplementation could prevent the development of obesity and reduce the risk factors for chronic disease in rats fed a high-fat (60 % fat) diet. Male Sprague-Dawley rats (n = 30 per dietary treatment) were meal-fed (3 meals/day) either a control, low-fat diet (LF), control + leucine (LFL), high-fat (HF), or high-fat + leucine (HFL) for 42 days. On day 42, rats were sacrificed at 0, 30, or 90 min postprandial. Animals fed the HF and HFL diets had higher (P < 0.05) final body weights and weight gain compared to animals fed the LF and LFL diets. Leucine supplementation increased epididymal fat mass (P < 0.05) and decreased muscle mass (P < 0.05). There was no effect of leucine supplementation on postprandial glucose or insulin response. However, there was a significant effect (P < 0.05) of diet and time on free fatty acid concentrations. There was no effect of leucine on muscle markers of protein synthesis (4E-BP1, p70S6K) or energy metabolism (Akt, AMPK). Leucine supplementation decreased (P < 0.05) PGC1α expression and increased (P < 0.05) PPARγ expression in skeletal muscle. In conclusion, long-term leucine supplementation does not prevent weight gain, improve body composition, or improve glycemic control in rats fed a high-fat diet (AU)


No disponible


Assuntos
Animais , Masculino , Ratos , Glicemia/metabolismo , Gorduras na Dieta/administração & dosagem , Suplementos Nutricionais , Obesidade/metabolismo , Aumento de Peso , Leucina/administração & dosagem , Proteínas Serina-Treonina Quinases , Tecido Adiposo , Composição Corporal , Metabolismo Energético , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Expressão Gênica , Biomarcadores/metabolismo , Biossíntese de Proteínas , Ratos Sprague-Dawley , Músculo Esquelético
9.
Rev. neurol. (Ed. impr.) ; 63(4): 160-164, 16 ago., 2016.
Artigo em Espanhol | IBECS | ID: ibc-155476

RESUMO

Introducción. La leucinosis es una metabolopatía neonatal grave. Es consecuencia del déficit enzimático determinado genéticamente del complejo descarboxilasa-dihidrolipoil transacilasa y dihidrolipoil deshidrogenasa, y del acúmulo consecuente de los metabolitos precursores, aminoácidos ramificados de cadena larga y sus alfa-cetoácidos. Son potentes neurotóxicos, responsables del rápido establecimiento de edema y desmielinización cerebral difusa. La demora en el diagnóstico suele provocar graves secuelas psicomotoras o incluso la muerte. Caso clínico. Se presenta una paciente neonata con encefalopatía neonatal grave, crisis epilépticas y un electroencefalograma (EEG) con unas características especiales que orientó el diagnóstico hacia una posible leucinosis. El diagnóstico temprano permitió instaurar rápidamente el tratamiento específico y conseguir una evolución favorable de la paciente. Conclusiones. El EEG en pacientes con sospecha de encefalopatía neonatal ofrece información funcional de alta rentabilidad con un bajo coste, en especial por promover diagnósticos y tratamientos tempranos. El EEG en la leucinosis presenta signos peculiares, reconocibles en períodos tempranos en la mayor parte de los afectados, como ocurrió en el caso descrito. Parece recomendable integrar el EEG en el cribado de encefalopatías neonatales por ser una técnica diagnóstica valiosa, inocua y, por lo general, accesible y especialmente de ayuda en metabolopatías tratables, como la leucinosis (AU)


Introduction. Leucinosis is a severe neonatal metabolic disease. It is the consequence of the genetically determined enzyme deficiency of the complex formed by decarboxylase-dihydrolipoyl transacylase and dihydrolipoyl dehydrogenase, and of the subsequent accumulation of precursor metabolites, long branched-chain amino acids and their alpha ketoacids. They are powerful neurotoxins, responsible for the swift onset of oedema and diffuse cerebral demyelination. Delays in its diagnosis usually result in severe psychomotor sequelae or even death. Case report. We report the case of a newborn female patient with severe neonatal encephalopathy, epileptic seizures and an electroencephalogram (EEG) with certain special characteristics that guided the diagnosis towards that of possible leucinosis. Early diagnosis makes it possible to establish specific treatment and achieve a favourable patient outcome. Conclusions. An EEG in patients with suspected neonatal encephalopathy offers highly cost-effective functional information at a low cost, especially because it promotes early diagnoses and treatments. In cases of leucinosis, EEG presents peculiar signs that are easily recognisable in early periods in most patients, as occurred in the case reported here. We believe EEG should be included in screening for neonatal encephalopathies because it is a valuable, innocuous and generally accessible diagnostic technique. It is especially helpful in treatable metabolic diseases, such as leucinosis (AU)


Assuntos
Humanos , Feminino , Recém-Nascido , Doença da Urina de Xarope de Bordo/complicações , Doença da Urina de Xarope de Bordo/terapia , Doença da Urina de Xarope de Bordo , Eletroencefalografia/instrumentação , Eletroencefalografia/métodos , Eletroencefalografia , Encefalopatias/complicações , Encefalopatias , Leucina/análise , Leucina/sangue , Hipotonia Muscular/complicações , Espectroscopia de Ressonância Magnética/métodos , Mesencéfalo , Cérebro
10.
J. physiol. biochem ; 69(1): 155-163, mar. 2013.
Artigo em Inglês | IBECS | ID: ibc-121998

RESUMO

Body weight is determined by the balance between energy intake and energy expenditure. When energy intake exceeds energy expenditure, the surplus energy is stored as fat in the adipose tissue, which causes its expansion and may even lead to the development of obesity. Thus, there is a growing interest to develop dietary interventions that could reduce the current obesity epidemic. In this regard, data from a number of in vivo and in vitro studies suggest that the branched-chain amino acid leucine influences energy balance. However, this has not been consistently reported. Here, we review the literature related to the effects of leucine on energy intake, energy expenditure and lipid metabolism as well as its effects on the cellular activity in the brain (hypothalamus) and in peripheral tissues (gastro-intestinal tract, adipose tissue, liver and muscle) regulating the above physiological processes. Moreover, we discuss how obesity may influence the actions of this amino acid (AU)


Assuntos
Humanos , Leucina/metabolismo , Obesidade/fisiopatologia , Ingestão de Energia/fisiologia , Aminoácidos de Cadeia Ramificada/fisiologia
11.
Trauma (Majadahonda) ; 24(1): 6-11, ene.-mar. 2013. tab
Artigo em Espanhol | IBECS | ID: ibc-111452

RESUMO

Objetivo: Analizar un programa de ejercicio físico moderado y sus efectos sobre la masa muscular y la tolerancia al esfuerzo en pacientes con cirrosis. Pacientes y métodos: Se estudiaron 17 pacientes con cirrosis hepática compensada divididos aleatoriamente en dos grupos: grupo ejercicio (n=8), que realizó un programa de ejercicio físico moderado durante 12 semanas, y grupo control (n=9). Todos los pacientes recibieron 10 g/día de leucina. Se analizaron cambios antropométricos, tolerancia al ejercicio y calidad de vida; además, se evaluó la seguridad durante el programa. Resultados: En el grupo ejercicio se observó un aumento en el perímetro del m. cuádriceps (p=0,02) y una mejora de la tolerancia al esfuerzo en el test de la marcha (p=0,01) y el test de los escalones (p=0,02). Además, en este grupo mejoró la calidad de vida de forma significativa. No observamos complicaciones de la cirrosis, deterioro hemodinámico o de la función renal en ninguno de los dos grupos durante el estudio. Conclusión: El ejercicio físico moderado en pacientes con cirrosis compensada es seguro, aumenta la masa muscular y mejora la tolerancia al esfuerzo y la calidad de vida (AU)


Objetive: To evaluate the efficacy and safety of an exercise programme to increase muscle mass, effort tolerance and quality of life in cirrhotic patients. Patients and methods: Seventeen compensated cirrhotic patients were randomized into either an exercise group (n=8) or a control group (n=9). The programme of moderate exercise was given for 12 weeks. All patients received oral leucine (10 g/day) during the study. Anthropometric measurements, effort tolerance and quality of life were determined at study start and end. We also analysed the safety during the study. Results: In the exercise group thigh circumference increased (p=0.02) and effort tolerance improved (p=0.01) and 2-min step test (p=0.02). Moreover, quality of life improved significantly in this group. In the control group there were no statistically significant changes in any of the studied parameters. We did not observe complications of cirrhosis in either group. Conclusion: Our results suggest that moderate physical exercise in patients with compensated cirrhosis is safe and improves quality of life, effort tolerance and muscle mass (AU)


Assuntos
Humanos , Masculino , Feminino , Exercício Físico/fisiologia , Leucina/uso terapêutico , Qualidade de Vida , Aminoácidos de Cadeia Ramificada/metabolismo , Aminoácidos de Cadeia Ramificada/uso terapêutico , Cirrose Hepática/tratamento farmacológico , Antropometria/instrumentação , Antropometria/métodos , Cirrose Hepática/cirurgia , Cirrose Hepática/terapia
12.
J. physiol. biochem ; 68(4): 493-501, dic. 2012.
Artigo em Inglês | IBECS | ID: ibc-122298

RESUMO

Nutritional supplementation with some amino acids may influence host’s responses and also certain mechanism involved in tumor progression. It is known that exercise influences body weight and muscle composition. Previous findings from our group have shown that leucine has beneficial effects on protein composition in cachectic rat model as the Walker 256 tumor. The main purpose of this study was to analyze the effects of light exercise and leucine and/or glutamine-rich diet in body composition and skeletal muscle protein synthesis and degradation in young tumor-bearing rats. Walker tumor-bearing rats were subjected to light aerobic exercise (swimming 30 min/day) and fed a leucine-rich (3%) and/or glutamine-rich (4%) diet for 10 days and compared to healthy young rats. The carcasses were analyzed as total water and fat body content and lean body mass. The gastrocnemious muscles were isolated and used for determination of total protein synthesis and degradation. The chemical body composition changed with tumor growth, increasing body water and reducing body fat content and total body nitrogen. After tumor growth, the muscle protein metabolism was impaired, showing that the muscle protein synthesis was also reduced and the protein degradation process was increased in the gastrocnemius muscle of exercised rats. Although short-term exercise (10 days) alone did not produce beneficial effects that would reduce tumor damage, host protein metabolism was improved when exercise was combined with a leucine-rich diet. Only total carcass nitrogen and protein were recovered by a glutamine-rich diet. Exercise, in combination with an amino acid-rich diet, in particular, leucine, had effects beyond reducing tumoral weight such as improving protein turnover and carcass nitrogen content in the tumor-bearing host (AU)


Assuntos
Animais , Ratos , Exercício Físico/fisiologia , Leucina/farmacocinética , Glutamina/farmacocinética , Neoplasias/patologia , Substâncias Protetoras/farmacocinética , Modelos Animais de Doenças , Suplementos Nutricionais , Antineoplásicos/farmacocinética , Composição Corporal
13.
J. physiol. biochem ; 66(2): 117-125, jun. 2010.
Artigo em Inglês | IBECS | ID: ibc-122835

RESUMO

No disponible


The sodium–calcium exchanger (NCX) plays a major role in the regulation of cytosolic Ca2+ in muscle cells. In this work, we performed force experiments to explore the role of NCX during contraction and relaxation of Cch-stimulated guinea pig tracheal smooth muscle strips. This tissue showed low sensitivity to NCX inhibitor KB-R7943 (IC50, 57 ± 2 µM), although a complete relaxation was obtained by NCX inhibition at 100 µM. Interestingly, relaxation after washing the agonist was prolonged in the absence of external Na+, whereas washing without Na+ and in the presence of KB-R7943 resembled control conditions with physiological solution. Altogether, this suggests the reversal of NCX to a Ca2+ influx mode by the manipulation on the Na+ gradient, which can be inhibited by KB-R7943. In order to understand the low sensitivity to KB-R7943, we studied the molecular aspects of the NCX expressed in this tissue and found that the isoform of NCX expressed is 1.3, similar to that described in human tracheal smooth muscle. Sequencing revealed that amino acid 19 in exon B is phenylalanine, whereas in its human counterpart is leucine, and that the first amino acid after exon D is aspartate instead of glutamate in humans. Results herein presented are discussed in term of their possible functional implications in the exchanger activity and thus in airway physiology (AU)


Assuntos
Humanos , Cobaias , Animais , Trocador de Sódio e Cálcio/antagonistas & inibidores , Fenilalanina/análise , Leucina/análise , Aspartato Quinase/análise , Ácido Glutâmico/análise , Trocador de Sódio e Cálcio , Cobaias
14.
An. pediatr. (2003, Ed. impr.) ; 67(4): 337-343, oct. 2007. tab
Artigo em Es | IBECS | ID: ibc-056409

RESUMO

Introducción La enfermedad de la orina con olor a jarabe de arce (MSUD) es un raro trastorno de herencia autosómica recesiva en el que, debido a la deficiencia enzimática en el complejo deshidrogenasa de los α-cetoácidos de cadena ramificada, se produce acumulación de los aminoácidos leucina, isoleucina, valina y aloisoleucina y sus productos metabólicos en células y líquidos biológicos, lo que conduce a una disfunción cerebral grave. Pacientes y método Presentamos los tres casos de MSUD diagnosticados desde el año 2000 en Galicia, a partir de la puesta en marcha del Programa de Cribado Neonatal por espectrometría de masas en tándem (MS/MS) en muestra de sangre impregnada en papel. Se trata de dos formas clásicas y una intermedia de MSUD, una diagnosticada por el inicio clínico precoz y dos a través del cribado neonatal. Todos los casos fueron confirmados mediante estudio enzimático y genético. Se expone la situación clínica y bioquímica al diagnóstico y durante el seguimiento posterior. Los tres mantuvieron un adecuado control metabólico con concentraciones medias de leucina a lo largo del tiempo cercanos al rango normal (220, 177 y 252 μmol/l, respectivamente). Presentaron descompensaciones moderadas y sólo superaron de forma aislada, un día en dos de los pacientes, los 1.000 μmol/l de leucina. Los cocientes de desarrollo en los tres casos están en rango normal. Resultados A la vista de nuestros resultados, consideramos clave para mejorar el pronóstico de los pacientes con MSUD: la inclusión de esta enfermedad dentro de los programas de cribado neonatal con toma de muestra precoz, a los dos o tres días de vida; un tratamiento agresivo en la fase inicial y en las crisis por descompensación metabólica; un control evolutivo estricto con el fin de prevenir descompensaciones, y la monitorización de aminoácidos ramificados de forma cómoda para el paciente (sobre muestra de sangre en papel) manteniendo concentraciones de leucina inferiores a 300 μmol/l


Introduction Maple syrup urine disease (MSUD) is a rare autosomal recessive disorder caused by an inherited deficiency of branched chain α-ketoacid dehydrogenase activity. Accumulation of the amino acids leucine, isoleucine, valine and alloisoleucine and their metabolic products in cells and biological fluids results in severe brain dysfunction. Patients and methods We present three cases of MSUD diagnosed in Galicia since 2000, the year in which the Extended Newborn Screening Program by tandem mass spectrometry was started in this region. One of the patients was diagnosed on the basis of early clinical presentation and the others by neonatal screening. Enzymatic and molecular studies confirmed two classic cases of MSUD and an intermediate variant. We describe the clinical and biochemical details at confirmation of diagnosis and the long-term outcome of the three patients. Throughout follow-up, all the patients maintained adequate leucine levels, which were near the normal range (mean levels: 220, 177 and 252 μmol/L, respectively). Several moderate metabolic decompensations were observed but leucine levels only occasionally exceeded 1000 μmol/L (one day in two patients). IQ tests were performed in all patients and scores were within the normal range. In view of our results, we believe the following measures are essential to improve the prognosis of MSUD: inclusion of this disease in Expanded Neonatal Screening Programs with early samples (at 2-3 days of life); aggressive treatment in the initial phase and during acute decompensations; strict metabolic control to prevent crises, monitoring of branched-chain amino acids (dried blood spot sample), and maintenance of long term plasma leucine levels below 300 μmol/L


Assuntos
Masculino , Feminino , Recém-Nascido , Humanos , Doença da Urina de Xarope de Bordo/diagnóstico , Doença da Urina de Xarope de Bordo/terapia , Aminoácidos de Cadeia Ramificada/sangue , Complexos Multienzimáticos/sangue , Complexos Multienzimáticos/genética , Doença da Urina de Xarope de Bordo/sangue , Aminoácidos de Cadeia Ramificada/metabolismo , 3-Metil-2-Oxobutanoato Desidrogenase (Lipoamida) , Alanina/sangue , Seguimentos , Furosemida/uso terapêutico , Isoleucina/sangue , Cetona Oxirredutases/sangue , Cetona Oxirredutases/genética , Leucina/sangue , Manitol/uso terapêutico , Mutação , Triagem Neonatal , Concentração Osmolar , Reação em Cadeia da Polimerase , Solução Salina Hipertônica/uso terapêutico , Valina/sangue
15.
Int. microbiol ; 10(1): 13-18, mar. 2007. ilus, tab
Artigo em En | IBECS | ID: ibc-054983

RESUMO

The kinetics of glucose and leucine uptake in attached and free-living prokaryotes in two types of microcosms with different nutrient qualities were compared. Microcosm type M1, derived from unaltered seawater, and microcosm type M2, from phytoplankton cultures, clearly expressed different kinetic parameters (Vmax/cell and K’ m). In aggregates with low cell densities (M1 microcosm), the attached prokaryotes benefited from attachment as reflected in the higher potential uptake rates, while in aggregates with high cell densities (M2 microcosm) differences in the potential uptake rates of attached and free-living prokaryotes were not evident. The aging process and the chemical changes in aggregates of M2 microcosms were followed for 15-20 days. The results showed that as the aggregates aged and prokaryotic abundance increased, attached prokaryotes decreased their potential uptake rate and their K’ m for substrate. This suggests an adaptive response by attached prokaryotes when aggregates undergo quantitative and qualitative impoverishment (AU)


No disponible


Assuntos
Células Procarióticas/imunologia , Fauna Marinha , Glucose/metabolismo , Leucina/metabolismo , Substratos para Tratamento Biológico
17.
Med. clín (Ed. impr.) ; 120(9): 337-339, mar. 2003.
Artigo em Es | IBECS | ID: ibc-19986

RESUMO

FUNDAMENTO Y OBJETIVO: Un polimorfismo común, Leu7Pro, en el péptido señal del neuropéptido Y se ha asociado con concentraciones elevadas de colesterol y arteriosclerosis en Finlandia. Nuestro objetivo fue estimar la prevalencia de dicho polimorfismo en la población española. PACIENTES Y MÉTODO: Se ha realizado un diseño transversal en 1.000 individuos procedentes de población mediterránea española. Se estudiaron dos muestras independientes compuestas por 486 individuos (muestra 1) y por 514 (muestra 2). Se determinó el polimorfismo Leu7Pro. RESULTADOS: Sólo se detectó un individuo portador de la variante Leu7Pro (0,1 por ciento). La frecuencia alélica para el alelo Pro7 en la población estudiada fue extremadamente baja: 0,005 (intervalo de confianza del 95 por ciento, 0,0001-0,0015).CONCLUSIONES: Esta bajísima prevalencia indica que el alelo Pro7 no es un importante factor genético determinante de obesidad, lípidos plasmáticos o alcoholismo en esta población (AU)


Assuntos
Pessoa de Meia-Idade , Criança , Adulto , Adolescente , Idoso , Idoso de 80 Anos ou mais , Masculino , Feminino , Humanos , Polimorfismo Genético , Polimorfismo Genético , Espanha , Prevalência , Neuropeptídeo Y , Laparoscopia , Obesidade , Prolina , Precursores de Proteínas , Estudos Transversais , Lipídeos , Leucina , Neoplasias
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