RESUMO
Metabolic profiling studies have highlighted increases in the plasma free fatty acid (FFA) and branched-chain amino acid (BCAA) concentrations, which are hallmarks of the obese and insulin-resistant phenotype. However, little is known about how the increase of the BCAA concentration modifies the metabolic fate of FFA, and vice versa, in adipocytes. Therefore, we incubated differentiated 3T3-L1 adipocytes or primary adipocytes from rats fed a control or a high-fat diet with: (1) 0, 250, 500 and 1000 µM of leucine and determined the oxidation and incorporation of [1-14C]-palmitate into lipids or proteins or (2) 0, 250, 500 or 1000 µM of palmitate and evaluated the oxidation and incorporation of [U-14C]-leucine into lipids or proteins. Leucine decreased palmitate oxidation and increased its incorporation into the lipid fraction in adipocytes; the latter was reduced in adipocytes from obese rats. However, palmitate increased leucine oxidation in adipocytes as well as reduced leucine incorporation into the protein and lipid fractions in adipocytes from obese rats. These results demonstrate that leucine modifies the metabolic fate of palmitate, and vice versa, in adipocytes and that the metabolic interaction between leucine and palmitate catabolism is altered in adipocytes from obese rats.
Assuntos
Adipócitos/metabolismo , Leucina/metabolismo , Obesidade/metabolismo , Palmitatos/metabolismo , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Animais , Carnitina O-Palmitoiltransferase/genética , Dieta Hiperlipídica/efeitos adversos , Relação Dose-Resposta a Droga , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Leucina/administração & dosagem , Leucina/farmacocinética , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Proteínas de Membrana Transportadoras/genética , Camundongos , Transportadores de Ácidos Monocarboxílicos , Obesidade/patologia , Palmitatos/administração & dosagem , Palmitatos/farmacocinética , Enzima Bifuncional do Peroxissomo/genética , Ratos Endogâmicos , Ratos Sprague-DawleyRESUMO
Associadas a projetos de construção da ideia de nação, no Brasil monárquico foram encaminhadas, pelo governo imperial, algumas iniciativas no sentido de materializar propostas de educação física. O objetivo deste artigo é investigar os sentidos e significados atribuídos ao tema na legislação e nos relatórios anuais do Ministério dos Negócios do Império (1831-1889), com especial interesse pelo que se refere ao Rio de Janeiro. A abordagem do assunto nas fontes pesquisadas evidencia que as visões sobre a educação física se deram a partir de uma matriz que articulava concepções de moral, saúde e civilização, tendo que lidar com as condições concretas de um país recém-independente, periférico e com uma burocracia ainda em formação.
In association with its nation building projects, the imperial government in Brazil under monarchic rule took some concrete actions based on proposals for physical education. The aim of this article is to investigate the meanings and significations attributed to this subject in the legislation and the annual reports issued by the Ministry of Business of the Empire (1831-1889), giving special attention to Rio de Janeiro. The approach to the subject in the sources researched demonstrates that the views of physical education took shape through a web of ideas that associated moral, health and civilization conceptions, in a bid to deal with the concrete circumstances of a newly independent peripheral nation with a bureaucratic structure in the process of formation.
Assuntos
Animais , Feminino , Camundongos , Carcinoma Pulmonar de Lewis/secundário , Catepsina B/antagonistas & inibidores , Catepsinas/antagonistas & inibidores , Endopeptidases , Leucina/análogos & derivados , Neoplasias Hepáticas Experimentais/prevenção & controle , Neoplasias Hepáticas Experimentais/secundário , Invasividade Neoplásica/prevenção & controle , Catepsina L , Colágeno , Cisteína Endopeptidases , Carcinoma Pulmonar de Lewis/metabolismo , Combinação de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Laminina , Leucina/farmacocinética , Leucina/farmacologia , Neoplasias Hepáticas Experimentais/enzimologia , Proteoglicanas , Células Tumorais CultivadasRESUMO
INTRODUCTION: Familial hypobetalipoproteinemia (FHBL) is an autosomal dominant disease characterized by abnormally low levels of apolipoprotein-B (apoB) containing lipoproteins. FHBL is caused by APOB, PCSK9 or ANGPTL3 mutations or is associated with loci located in chromosomes 10 and 3p21. However, other genes should be involved. This study describes the kinetic parameters of the apoB containing lipoproteins and sequence abnormalities of the APOB and PCSK9 genes of FHBL patients identified in a large hospital based survey. MATERIAL AND METHODS: Cases with primary or secondary causes of hypobetalipoproteinemia were identified. ApoB kinetics were measured in cases with primary forms in whom truncated forms of apoB were not present in VLDL (n = 4). A primed constant infusion of [(13)C] leucine was administered, VLDL and LDL apoB production and catabolic rates measured by a multicompartmental model and compared to normolipemic controls. In addition, these subjects had an abdominal ultrasound and direct sequencing was carried out for the PCSK9 and apoB genes. RESULTS: Three individuals had normal apoB production with increased catabolic rate; the remaining had reduced synthetic and catabolic rates. Various polymorphisms, some of them previously unreported (*), in the PCSK9 gene (R46L, A53V, I474V, D480N*, E498K*) and in the apoB gene (N441D*, Y1395C, P2712L, D2285E*, I2286V, T3540S*, T3799M*) were found in the FHBL patients. We found hepatic ultrasound changes of hepatic steatosis in only one of the four probands. CONCLUSION: FHBL without truncated apoB is a heterogeneous disease from a metabolic and a genetic perspective. Hypobetalipoproteinemia is a risk factor but not an obligate cause of steatosis.
Assuntos
Apolipoproteína B-100/genética , Fígado Gorduroso , Hipobetalipoproteinemias , Serina Endopeptidases/genética , Adulto , Isótopos de Carbono , Coleta de Dados , Fígado Gorduroso/epidemiologia , Fígado Gorduroso/genética , Fígado Gorduroso/metabolismo , Feminino , Genótipo , Hospitais/estatística & dados numéricos , Humanos , Hipobetalipoproteinemias/epidemiologia , Hipobetalipoproteinemias/genética , Hipobetalipoproteinemias/metabolismo , Pacientes Internados/estatística & dados numéricos , Leucina/farmacocinética , Fígado/diagnóstico por imagem , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Modelos Genéticos , Hepatopatia Gordurosa não Alcoólica , Linhagem , Polimorfismo Genético , Pró-Proteína Convertase 9 , Pró-Proteína Convertases , UltrassonografiaRESUMO
Geotrichum candidum growth on ammonium and leucine as nitrogen sources and glucose as a carbon source was examined. A clear preference of G. candidum for ammonium over leucine as a nitrogen source was shown. Indeed, ammonium was completely exhausted at the end of exponential growth after less than 35 hrs of culture; in contrast only 5 percent of leucine was concomitantly assimilated. Growth continued at slower rates on glucose and leucine as carbon and nitrogen sources respectively, and at the end of culture (185 hrs), leucine was completely exhausted.
Assuntos
Animais , Compostos de Amônio Quaternário/metabolismo , Compostos de Amônio Quaternário/uso terapêutico , Geotrichum/crescimento & desenvolvimento , Geotrichum , Leucina/farmacocinética , Leucina/metabolismo , Leucina/uso terapêutico , Aminoácidos , Fermentação , Glucose/química , Glucose/uso terapêutico , Nitrogênio/química , Nitrogênio/uso terapêuticoRESUMO
We investigated whether supplementation with an aromatic amino acid (AAA) cocktail consisting of 0.5 mmol each of phenylalanine, tryptophan, and tyrosine compared with isonitrogenous amounts of alanine (Ala) would improve measures of protein kinetics in 14 (8 with AAA, 6 Ala) children with edematous malnutrition (aged 6-24 mo) during the infected acute malnourished state. Supplementation started immediately after the baseline experiment, 2 d postadmission and continued to the end of the acute phase of treatment. The second (postsupplementation) experiment was done approximately 12 d postadmission. We measured leucine kinetics, phenylalanine and tyrosine fluxes, using an i.g. 8-h prime continuous infusion of (2)H(3)-leucine, and an i.v. 6-h prime continuous infusion of (13)C-leucine, (2)H(2)-tyrosine, and (2)H(5)-phenylalanine in the fed state. Leucine flux tended to be faster (P = 0.06) in the AAA group compared with Ala group after supplementation (mean difference +/- SEM): 22.6 +/- 10.9 micromol/(kg . h). The rate of leucine appearance from protein breakdown [28.1 +/- 9.4 micromol/(kg . h)] and the nonoxidative disposal of leucine [i.e., leucine to protein synthesis; 35.4 +/- 12.9 micromol/(kg . h)] were faster (P < 0.02) in the AAA group than in the Ala group. There was no significant effect of supplementation on leucine splanchnic metabolism, phenylalanine, and tyrosine fluxes. These findings are consistent with the hypothesis that the blunting of the protein catabolic response to infection in children with edematous malnutrition syndrome is due to limited availability of aromatic amino acids.
Assuntos
Aminoácidos Aromáticos/administração & dosagem , Aminoácidos Aromáticos/farmacocinética , Edema/terapia , Infecções/terapia , Leucina/farmacocinética , Desnutrição Proteico-Calórica/terapia , Alanina/administração & dosagem , Antropometria , Água Corporal/fisiologia , Deutério , Edema/complicações , Nutrição Enteral , Humanos , Lactente , Infecções/complicações , Intubação Gastrointestinal , Cinética , Fenilalanina/administração & dosagem , Desnutrição Proteico-Calórica/complicações , Proteínas/metabolismo , Triptofano/administração & dosagem , Tirosina/administração & dosagemRESUMO
Bauhinia forficata is one of the Bauhinia species mostly used as an antidiabetic herbal remedy in Brazil. Kaempferitrin (kaempferol-3,7-O-(alpha)-L-dirhamnoside) is the predominant flavonol glycoside found in the B. forficata leaves. The aim of the present work was to study the long-term effect of kaempferitrin on glycaemia in diabetic rats, as well as the in vitro effect of this compound on 14C-D-glucose uptake and 14C-leucine incorporation into protein in normal rat soleus muscle. Kaempferitrin was found to have an acute lowering effect on blood glucose in diabetic rats and to stimulate the glucose uptake percentile, as efficiently as insulin in muscle from normal rats. This compound did not have any effect on glucosuria or on protein synthesis in muscle from normal and diabetic animals. However, the protein synthesis in the kaempferitrin-treated groups was maintained at the same level as the respective controls. Thus, the hypoglycaemic effect and the prompt efficiency of the kaempferitrin in stimulating [U-14C]-2-deoxi-D-glucose uptake in muscle -constitute the first evidence to indicate that the acute effect of this compound on blood glucose lowering may occur as a consequence of the altered intrinsic activity of the glucose transporter (Vmax or glucose transporters translocation?) not involving directly the synthesis of new carriers.
Assuntos
Bauhinia/química , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Insulina/farmacologia , Quempferóis/farmacologia , Músculo Esquelético/metabolismo , Animais , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Radioisótopos de Carbono , Desoxiglucose/farmacocinética , Interações Medicamentosas , Glicosúria/tratamento farmacológico , Leucina/farmacocinética , Masculino , Músculo Esquelético/efeitos dos fármacos , Folhas de Planta/química , Distribuição Aleatória , Ratos , Ratos WistarRESUMO
OBJECTIVE: Protein malnutrition is characterized by a number of morphologic and physiologic alterations, including intestinal mucosal atrophy and impaired nutrient absorption. Impaired absorption accentuates nutritional deficiency and accelerates body weight loss and changes in body chemistry. Because leucine is a ketogenic and oxidative amino acid and stimulates the protein synthesis, we examined the ability of young rats to recover from protein malnutrition by feeding them a control balanced or a leucine-rich diet for 60 d. METHODS: At the end of the 60-d period, body, liver, and muscle weights; glucose, methionine, and leucine intestinal absorption; and carcass chemical composition were evaluated. RESULTS: Body weight gain was higher in the control balanced and leucine-rich groups than in control rats, indicating that adequate refeeding allows body weight to recover in these groups. Methionine and glucose absorptions were impaired in malnourished rats but were restored after nutritional recovery. The leucine-rich diet resulted in an increase in carcass collagen nitrogen but maintained the carcass structural nitrogen. CONCLUSIONS: These results indicated that leucine supplementation during nutritional recovery from protein malnutrition improves protein carcass restoration. However, the precise mechanism of the leucine effects involved in this response remains to be elucidated.
Assuntos
Composição Corporal/efeitos dos fármacos , Proteínas Alimentares/administração & dosagem , Absorção Intestinal/efeitos dos fármacos , Leucina/administração & dosagem , Leucina/farmacocinética , Desnutrição Proteico-Calórica/dietoterapia , Animais , Peso Corporal/efeitos dos fármacos , Masculino , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Nitrogênio/metabolismo , Tamanho do Órgão/efeitos dos fármacos , Desnutrição Proteico-Calórica/metabolismo , Distribuição Aleatória , Ratos , Ratos WistarRESUMO
The typical form of hemolytic uremic syndrome (D+HUS) is a thrombotic microangiopathy that causes acute renal failure in children. The etiology of this disease is a toxin called Shiga-like toxin (Stx), present in certain strains of gram-negative bacteria. Vascular endothelial cell (EC) injury appears to be central in the pathogenesis of D+HUS. Thrombomodulin (TM) is a glycoprotein present in EC with anti-thrombogenic properties. The objective of this study was to investigate the effects of Stx on the surface expression of TM in EC using an in vitro culture of human glomerular microvascular endothelial cells. We also evaluated other inflammatory mediators [tumor necrosis factor-alpha (TNF-alpha) and lipopolysaccharide], which are known to increase Stx receptor expression and are potentially involved in the pathogenesis of D+HUS. Stx2 induced a significant decrease of TM expression in this cell type after pre-incubation with TNF-alpha. This decrease could not be attributed to the inhibition of protein synthesis only, as cycloheximide, another inhibitor of protein synthesis, did not affect TM surface expression. These results suggest that the Stx2-induced decrease of TM expression in glomerular EC might contribute to the local procoagulant state present in D+HUS.
Assuntos
Endotélio Vascular/metabolismo , Mesângio Glomerular/irrigação sanguínea , Síndrome Hemolítico-Urêmica/etiologia , Síndrome Hemolítico-Urêmica/metabolismo , Trombomodulina/metabolismo , Células Cultivadas , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Endotélio Vascular/citologia , Humanos , Mediadores da Inflamação/metabolismo , Leucina/farmacocinética , Microcirculação , Toxina Shiga II/farmacologia , TrítioRESUMO
The bacterioplanktonic abundance, biomass, and production within a tropical lagoon (Cabiúnas, Brazil) and two temperate lakes (Stechlin and Dagow, Germany) were compared. Bacterial abundance and production were significantly different among the three water bodies. The lowest bacterial production (0.8 microg C l(-1) d(-1)) was observed in the tropical Cabiúnas Lagoon despite its higher mean temperature and dissolved organic carbon concentration. Highest bacterioplankton abundance (2.6 x 10(9) cells l(-1)) and production (68.5 microg C l(-1) d(-1)) were measured in eutrophic Lake Dagow. In oligotrophic Lake Stechlin, the lowest bacterial biomass (48.05 microg C l(-1)) was observed because of lower bacterial biovolume (0.248 microm(3)) and lower bacterial abundance. Bacterial populations in the temperate lakes show higher activity (production/biomass ratio) than in the tropical lagoon. The meaning of isotopic dilution and leucine incorporation by non-bacterial micro-organisms were evaluated in the oligotrophic temperate system. Leucine uptake by non-bacterial micro-organisms did not have significant influence on bacterial production.
Assuntos
Bactérias/crescimento & desenvolvimento , Biomassa , Água Doce/microbiologia , Plâncton/fisiologia , Animais , Bactérias/isolamento & purificação , Brasil , Contagem de Colônia Microbiana , Alemanha , Leucina/farmacocinética , TemperaturaRESUMO
The bacterioplanktonic abundance, biomass, and production within a tropical lagoon (Cabiúnas, Brazil) and two temperate lakes (Stechlin and Dagow, Germany) were compared. Bacterial abundance and production were significantly different among the three water bodies. The lowest bacterial production ( 0.8mug C l-1 d-1) was observed in the tropical Cabiúnas Lagoon despite its higher mean temperature and dissolved organic carbon concentration. Highest bacterioplankton abundance ( 2.6 x 10(9) cells l-1) and production ( 68.5mug C l-1 d-1) were measured in eutrophic Lake Dagow. In oligotrophic Lake Stechlin, the lowest bacterial biomass ( 48.05mug C l-1) was observed because of lower bacterial biovolume ( 0.248mum³) and lower bacterial abundance. Bacterial populations in the temperate lakes show higher activity (production/biomass ratio) than in the tropical lagoon. The meaning of isotopic dilution and leucine incorporation by non-bacterial micro-organisms were evaluated in the oligotrophic temperate system. Leucine uptake by non-bacterial micro-organisms did not have significant influence on bacterial production