RESUMO
Maple syrup urine disease (MSUD) is an inherited metabolic disorder caused by a deficiency in branched-chain alpha-ketoacid dehydrogenase complex (BCKAC). The treatment is a standard therapy based on a protein-restricted diet with low branched-chain amino acids (BCAA) content to reduce plasma levels and, consequently, the effects of accumulating their metabolites, mainly in the central nervous system. Although the benefits of dietary therapy for MSUD are undeniable, natural protein restriction may increase the risk of nutritional deficiencies, resulting in a low total antioxidant status that can predispose and contribute to oxidative stress. As MSUD is related to redox and energy imbalance, melatonin can be an important adjuvant treatment. Melatonin directly scavenges the hydroxy radical, peroxyl radical, nitrite anion, and singlet oxygen and indirectly induces antioxidant enzyme production. Therefore, this study assesses the role of melatonin treatment on oxidative stress in brain tissue and behavior parameters of zebrafish (Danio rerio) exposed to two concentrations of leucine-induced MSUD: leucine 2 mM and 5mM; and treated with 100 nM of melatonin. Oxidative stress was assessed through oxidative damage (TBARS, DCF, and sulfhydryl content) and antioxidant enzyme activity (SOD and CAT). Melatonin treatment improved redox imbalance with reduced TBARS levels, increased SOD activity, and normalized CAT activity to baseline. Behavior was analyzed with novel object recognition test. Animals exposed to leucine improved object recognition due to melatonin treatment. With the above, we can suggest that melatonin supplementation can protect neurologic oxidative stress, protecting leucine-induced behavior alterations such as memory impairment.
Assuntos
Doença da Urina de Xarope de Bordo , Melatonina , Animais , Leucina/efeitos adversos , Leucina/metabolismo , Doença da Urina de Xarope de Bordo/metabolismo , Peixe-Zebra/metabolismo , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Melatonina/farmacologia , Melatonina/uso terapêutico , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Estresse Oxidativo , Aminoácidos de Cadeia Ramificada/metabolismo , Superóxido Dismutase/metabolismoRESUMO
The objective of this study was to evaluate the standardized ileal digestible (SID) valine and SID leucine levels on performance, backfat thickness, longissimus dorsi depth, and biochemical blood parameters of starting gilts. A total of 72 gilts, with initial weight of 15.16±1.15 kg, were distributed in a randomized block design in a 2 × 4 factorial scheme, comprised of two SID leucine levels (1.20 and 1.77%) and four SID valine levels (0.58, 0.73, 0.88, and 1.03%), with nine replicates and one animal per experimental unit. No interactions were observed for growth performance parameters. Final weight and average daily gain presented linear and quadratic effects. Setting data to the quadratic model associated with the Linear Response Plateau model, the optimal level of SID valine for average daily gain was achieved at 0.703%. A quadratic effect was also observed for average daily feed intake (ADFI), estimating the highest ADFI at 0.822% of SID valine. No branched chain amino acid (BCAA) effects were observed for backfat thickness, longissimus dorsi depth, and lean meat percentage. The interaction between levels of BCAA showed that the highest SID leucine levels (1.77%) provided a high plasma urea concentration only at low SID valine levels (0.58 and 0.73%). The SID valine requirement of starting gilts for a maximum average daily gain is achieved at 0.703%, corresponding to 9.72 g day−1, and is not affected by SID leucine levels currently used in conventional diets.(AU)
Assuntos
Animais , Feminino , Suínos/fisiologia , Valina/efeitos adversos , Leucina/efeitos adversos , Gorduras/análiseRESUMO
BACKGROUND: Frailty is a multifactorial geriatric syndrome characterized by progressive decline in health and associated with decreased muscle mass, strength, and functional capacity. Resistance training (RT) combined with protein or amino acids supplementation has been shown to be promising for mitigating age-related impairments. AIM: To investigate the chronic effects of different strategies of protein and derivatives supplementation in association with RT on selected health-related parameters in pre-frail and frail elderly. METHODS: This is a series of double-blind, randomized, placebo-controlled, parallel-group clinical trials. Volunteers will be divided into nine groups, comprising four different sub-studies evaluating the effects of: isolated leucine supplementation (study 1); protein source (whey vs. soy - study 2); combination of whey protein and creatine (study 3); and sexual dimorphism on the response to protein intake and RT (males vs. females - study 4). Muscle cross-sectional area, fiber cross-sectional area, body composition, lower-limb maximal dynamic and isometric strength, functionality, lipid profile, biochemical parameters, renal function, quality of life, and nutritional status will be assessed before and after a 16-week intervention period. Data will be tested for normality and a mixed-model for repeated measures will be conducted to assess within- and between-group effects of the intervention on the dependent variables. Confidence intervals (95%), effect sizes, and relative changes will also be determined, with significance set at p < 0.05.
Assuntos
Envelhecimento , Proteínas Alimentares/uso terapêutico , Suplementos Nutricionais , Fenômenos Fisiológicos da Nutrição do Idoso , Músculo Esquelético/fisiologia , Treinamento Resistido , Sarcopenia/prevenção & controle , Idoso , Terapia Combinada , Proteínas Alimentares/efeitos adversos , Suplementos Nutricionais/efeitos adversos , Método Duplo-Cego , Feminino , Idoso Fragilizado , Fragilidade/etiologia , Fragilidade/prevenção & controle , Humanos , Leucina/efeitos adversos , Leucina/uso terapêutico , Masculino , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/fisiopatologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Sarcopenia/diagnóstico por imagem , Sarcopenia/fisiopatologia , Sarcopenia/terapia , Índice de Gravidade de Doença , Caracteres Sexuais , Proteínas de Soja/efeitos adversos , Proteínas de Soja/uso terapêutico , Ultrassonografia , Proteínas do Soro do Leite/efeitos adversos , Proteínas do Soro do Leite/uso terapêuticoRESUMO
Several studies showed that l-leucine supplementation reduces adiposity when provided before the onset of obesity. We studied rats that were exposed to a high-fat diet (HFD) for 10 weeks before they started to receive l-leucine supplementation. Fat mass was increased in l-leucine-supplemented rats consuming the HFD. Accordingly, l-leucine produced a hypothalamic pattern of gene expression that favors fat accumulation. In conclusion, l-leucine supplementation worsened the adiposity of rats previously exposed to HFD possibly by central mechanisms.
Assuntos
Adiposidade/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Suplementos Nutricionais , Hipotálamo/metabolismo , Leucina/efeitos adversos , Obesidade/patologia , Animais , Ingestão de Energia , Expressão Gênica , Leucina/administração & dosagem , Masculino , Ratos , Ratos WistarRESUMO
The characterization of the mechanisms underlying skeletal muscle atrophy under different conditions has been a constant focus of research. Among anti-atrophic therapies, amino acid supplementation, particularly with leucine, has received a lot of attention. Supplementation has been shown to have remarkable effects on muscle remodeling through protein turnover modulation. This may then impact physiological parameters related to muscle function, and even quality of life. In light of this, leucine supplementation could be a useful therapy for mitigating the atrophic effects of catabolic conditions. The purpose of this review is to present the major results of human studies evaluating the effects of leucine supplementation on structure and function of skeletal muscle in atrophic conditions such as muscle disuse, sarcopenia, and cancer.
Assuntos
Leucina/uso terapêutico , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/patologia , Atrofia Muscular/tratamento farmacológico , Doenças Musculares/tratamento farmacológico , Neoplasias/tratamento farmacológico , Ensaios Clínicos como Assunto , Suplementos Nutricionais/estatística & dados numéricos , Humanos , Leucina/efeitos adversos , Doenças Musculares/patologiaRESUMO
Se comunica el caso de un lactante de 3 meses de edad que presenta signos clínicos y de laboratorio correspondientes a un cuadro de hipoglicemia, el que se inicia poco después de comenzar a ingerir leche total. Hospitalizado, sufre una diarrea grave que obliga al uso de soluciones glucosalinas por vía endovenosa y posteriormente leche de soya, con lo que los episodios hipoglicémicos desaparecen. Al introducir en su dieta carne de vacuno vuelven a presentar-se las manifestaciones de hipoglicemia. Sospechado el diagnóstico de sensibilidad a la leucina, que se confirma con un test de tolerancia a ese amnioácido, se instala una dieta pobre en leucina. Controlado a los 21 meses de vida, el examen neurológico , el desarrollo psicomotor y pondoestatual son normales