RESUMO
The study of peptidoglycan-binding proteins frequently requires in vitro binding assays, in which the isolated peptidoglycan used as a substrate must be carefully quantified. Here, we describe an easy and sensitive assay for peptidoglycan quantification based on a modified Nelson-Somogyi reducing sugar assay. We report the response of this assay to different common sugars and adapt its use to peptidoglycan samples subjected to acid hydrolysis. This method showed better sensitivity than the peptidoglycan quantification method based on the acid detection of diaminopimelic acid. The method described in this work, besides being valuable in the characterization of peptidoglycan-binding proteins, is also useful for the quantification of reducing monosaccharides or polysaccharides after acid or hydrolysis.
Assuntos
Parede Celular , Açúcares , Bactérias/metabolismo , Parede Celular/metabolismo , Hidrólise , Peptidoglicano/metabolismoRESUMO
Dronedarone biodistribution in hyperlipidemia and dronedarone metabolism in hyperlipidemia or obesity were assessed. Male Sprague-Dawley rats were given either normal standard chow with water or various high-fat or high-carbohydrate diets for 14 weeks. There was also a nonobese hyperlipidemic group given poloxamer 407 intraperitoneally. Liver and intestinal microsomes were prepared and the metabolic conversion of dronedarone to desbutyldronedarone was followed. A biodistribution study of dronedarone given orally was conducted in hyperlipidemic and control normolipidemic rats. The metabolism of dronedarone to desbutyldronedarone in control rats was consistent with substrate inhibition. However in the treatment groups, the formation of desbutyldronedarone did not follow substrate inhibition; hyperlipidemia and high-calorie diets created remarkable changes in dronedarone metabolic profiles and reduction in formation velocities. Tissue concentrations of dronedarone were much higher than in plasma. Furthermore, in hyperlipidemia, plasma and lung dronedarone concentrations were significantly higher compared to normolipidemia.
Assuntos
Antiarrítmicos/metabolismo , Dieta Hiperlipídica/efeitos adversos , Dronedarona/metabolismo , Hiperlipidemias/metabolismo , Obesidade/complicações , Animais , Antiarrítmicos/administração & dosagem , Dronedarona/administração & dosagem , Hiperlipidemias/tratamento farmacológico , Hiperlipidemias/etiologia , Hiperlipidemias/patologia , Masculino , Obesidade/patologia , Ratos , Ratos Sprague-Dawley , Distribuição TecidualRESUMO
A bioethanol by-product, dried distiller's grains with solubles (DDGS) contains high levels of cellulose and starch. We hypothesized that combinations of solid-state fermentation (SSF) and digestion by black soldier fly larvae (BSFL) (Hermetia illucens) could increase the recovery of glucose from this by-product by concentrating and loosening the cellulose matrix through their activities. DDGS was individually fermented with Aspergillus niger, Aspergillus fumigatus, Trichoderma koningii, Phanerochaete chrysosporium, or Lactobacillus plantarum. The fermented DDGS was fed to BSFL, and glucose recoveries from spent feeds were conducted. SSF increases lipid and protein contents, supporting BSFL growth, and weakens the cellulosic matrix. BSFL use nutrients in SSF-DDGS, further concentrating and weakening the cellulose, i.e., DDGS is halved without changing the cellulose contents. For example, Lactobacillus plantarum SSF with BSFL culture concentrates the cellulose content from 9.7% to 26.5% of spent feed. Glucose recovery was determined using three sequential processes (free glucose determination, weak-acid hydrolysis of amorphous cellulose, and enzymatic hydrolysis of micronized crystalline cellulose). Total glucose obtained from 100 g of DDGS increased from 4.8 to 10.7 g. These results show that the combinations of SSF and BSFL could provide additional fermentable sugars (and insect biomass) from bioethanol by-products, suggesting a high productivity from the same feedstock.
Assuntos
Biocombustíveis , Grão Comestível/metabolismo , Fermentação , Glucose/metabolismo , Simuliidae/metabolismo , Animais , Larva/metabolismoRESUMO
Insects utilize sugars as their essential energy and nutrient sources; therefore, the sense of sugar detection plays a critical role in insect behaviours. Previously, using genomic and transcriptomic approaches, we identified eight putative sugar gustatory receptor (GR) genes from the cotton bollworm Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae). Here, we further validated these annotated sugar receptor genes (HarmGr4-HarmGr8 and HarmGr10-HarmGr12) and found HarmGr10 may be a pseudogene carrying a stop codon in the open reading frame. Sequence alignment revealed H. armigera sugar GR sequences are conserved at C-terminus and phylogenetic analysis showed that insect sugar GRs have evolved in a family-specific manner. Interestingly, all eight H. armigera sugar GRs are localized in a tandem array on the same scaffold of the genome. In silico gene expression and reverse transcription (RT)-PCR analysis showed that HarmGr10 is specifically expressed in male adult testes while HarmGr11 is specifically expressed in female adult ovaries, suggesting H. armigera sugar GRs may be involved in reproduction-related functions. This study improves our knowledge on insect sugar receptors and gustatory systems.
Assuntos
Proteínas de Insetos/genética , Lepidópteros/genética , Receptores de Superfície Celular/genética , Açúcares/metabolismo , Paladar , Animais , Sequência Conservada , Evolução Molecular , Feminino , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Lepidópteros/classificação , Masculino , Ovário/metabolismo , Filogenia , Domínios Proteicos , Pseudogenes , Receptores de Superfície Celular/química , Receptores de Superfície Celular/metabolismo , Testículo/metabolismoRESUMO
Potato plantlets inoculated with strain PsJN of the bacterium Burkholderia phytofirmans exhibit consistent and significant increases in plant growth under in vitro conditions, when compared with uninoculated plants. The greatest influence on the degree and type of growth enhancement that develops has been shown to be mediated by the sugar concentration in the agar media. Bacterial growth promotion has been suggested in other studies to be regulated by the sugar sensor enzyme hexokinase1, the role of which is activation of glucose phosphorylation. In this present study, we examined the co-relationship between root and stem development in potato plants treated with PsJN and the activity of hexokinase1. Plants grown in the presence of 1.5% and 3% sucrose showed increased levels of hexokinase1 activity only in the roots of inoculated plants, suggesting that the increased enzyme levels may be associated with root growth. Analysis for mRNA using reverse transcriptase did not reveal any significant differences in transcription levels of the gene between inoculated and uninoculated plants. When PsJN-inoculated plants were grown in 1.5% and 3% concentrations of glucose and fructose, stem height and mass, leaf number, root mass, and overall biomass increased. No growth promotion occurred when PsJN-inoculated plants were grown in 3% maltose. Subsequently, a hexokinase1 activity assay showed that PsJN-induced growth of potato plants was found to only occur when plants were grown in the presence of sugars that are recognized by the plant hexokinase1. The results suggest that PsJN may enhance sugar uptake in plants by direct or indirect stimulation of hexokinase1 activity in roots and this results in enhanced overall plant growth.
Assuntos
Burkholderia/fisiologia , Metabolismo dos Carboidratos/fisiologia , Hexoquinase/metabolismo , Solanum tuberosum/crescimento & desenvolvimento , Solanum tuberosum/microbiologia , Burkholderia/enzimologia , Burkholderia/genética , Clorofila/metabolismo , Frutose/metabolismo , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Glucose/metabolismo , Hexoquinase/genética , Maltose/metabolismo , Fosforilação , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/microbiologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Caules de Planta/crescimento & desenvolvimento , Caules de Planta/microbiologia , RNA de Plantas/genética , Sacarose/metabolismoRESUMO
Dietary recommendations to reduce sugars consumption may influence choices of sugars-containing foods and affect the intake of key micronutrients. We compared intakes of nutrients and food sources stratified by quintiles of total sugars in Canadian children (2-8 y) and adolescents (9-13 y, 14-18 y) using 24-hour dietary recalls from the 2015 Canadian Community Health Survey-Nutrition. Energy intakes did not differ across quintiles of sugars intake. Those with lower sugars intakes (Q1/Q3) generally had higher protein, fat, sodium, niacin, folate, and zinc and lower vitamin C compared with those with the highest sugars intakes (Q5). Q1 also had lower potassium but higher saturated fat compared with Q5. Further, Q1 generally had higher protein, fats, and niacin compared with Q3, while children in Q3 had higher potassium and riboflavin and older adolescents had higher calcium and fibre. Q5 had highest intakes of multiple sugar-containing food categories (e.g., fruit, confectionary, milks, cakes/pies/pastries), with higher sugars-sweetened beverages in adolescents. Q3 had higher fruit, milks, and fruit juice compared with Q1 and lower sugars/syrups/preserves, confectionary, and fruit juices compared with Q5. Certain nutrient-dense food sources of sugars (fruit, milks) may help increase key nutrients (potassium, calcium, fibre) in older adolescents with low sugars intakes. However, in those with the highest sugars intakes, nutrient-poor foods may displace nutrient-dense foods. Novelty: Canadian children and adolescents with lower sugars intake have better intakes of some nutrients. Energy intakes did not differ across sugars intake. Older adolescents with mean intakes of total sugars had better intakes of some key nutrients (potassium, calcium, fibre).
Assuntos
Nutrientes , Saúde Pública , Adolescente , Canadá , Criança , Estudos Transversais , Dieta , Ingestão de Energia , Humanos , Nutrientes/análise , Inquéritos Nutricionais , AçúcaresRESUMO
Obesity is associated with an energy imbalance that results from excessive energy intake, low diet quality, and a sedentary lifestyle. The increased consumption of a high-refined carbohydrate (HC) diet is strongly related to higher adiposity and low-grade inflammation. Aerobic training is a well-known nonpharmacological intervention to treat obesity and metabolic disturbances. However, the mechanisms through which aerobic training ameliorates the low-grade inflammation induced by an HC diet should be further investigated. Our hypothesis herein was that aerobic training would decrease the recruitment of leukocytes in adipose tissue, thereby reducing the levels of cytokines and improving metabolism in mice fed an HC diet. Male Balb/c mice were assigned to the following groups: control diet/nontrained (C-NT), control diet/trained (C-T), high-refined carbohydrate diet/nontrained (HC-NT), and high-refined carbohydrate diet/trained (HC-T). Mice were submitted to moderate-intensity training sessions that consisted of running 60 min per day for 8 weeks. An intravital microscopy technique was performed in vivo in anesthetized mice to visualize the microvasculature of the adipose tissue. The HC diet induced obesity and increased the influx of immune cells into the adipose tissue. In contrast, HC-T mice presented a lower adiposity and adipocyte area. Furthermore, relative to HC-NT mice, HC-T mice showed increased resting energy expenditure, decreased recruitment of immune cells in the adipose tissue, reduced cytokine levels, and ameliorated hyperglycemia and fatty liver deposition. Collectively, our data enhance understanding about the anti-inflammatory effect of aerobic training and shed light on the adipose tissue-mediated mechanisms by which training promotes a healthier metabolic profile.
Assuntos
Tecido Adiposo/citologia , Citocinas/análise , Leucócitos/citologia , Condicionamento Físico Animal , Animais , Dieta , Carboidratos da Dieta/administração & dosagem , Metabolismo Energético , Microscopia Intravital , Masculino , Camundongos Endogâmicos BALB C , Camundongos Obesos , Consumo de Oxigênio , Distribuição AleatóriaRESUMO
Dietary factors are major contributors to morbidity and mortality, and significant attention is being paid to interventions to support healthy eating, including through the creation of a healthier food supply. The objective of this study was to inform interventions to support healthy eating by examining the top dietary sources of calories, sodium, sugars, and saturated fats among Canadians in relation to sex, age, and income. We drew upon data from the 2015 Canadian Community Health Survey, which collected interviewer-administered 24-h dietary recalls from Canadians who were 1 year of age and older (n = 20 176), residing in the 10 provinces. Foods and beverages were grouped into 91 mutually exclusive categories (e.g., 100% fruit juice, fruit drinks). On the basis of the average proportion contributed, the top 20 sources of each dietary component were identified for all individuals and by sex-age and income groups. The mean amount of each dietary component contributed by each category (per capita and per consumer) and the proportions of persons consuming items in each category were also examined. Top sources included commonly consumed items (e.g., breads and flatbreads as sources of sodium), as well as those high in a given dietary component (e.g., soda as a source of sugars). Several food and beverage categories were top contributors to more than one dietary component examined, suggesting possible priorities for intervention and future analyses. The identification of major sources of calories and nutrients of concern can inform population health efforts, such as reformulation, to improve the health of Canadians.
Assuntos
Dieta , Gorduras na Dieta/análise , Açúcares da Dieta/análise , Ingestão de Energia , Sódio na Dieta/análise , Adolescente , Adulto , Idoso , Canadá , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Adulto JovemRESUMO
It is debated whether carbohydrate restriction has metabolic advantage for its variable weight loss. Five-week-old male mice fed a high-fat diet and receiving a glycolytic inhibitor, 2-deoxyglucose, died within 9 days. They exhibited greater decreases in rectal temperature, appetite, and decline in body weight accompanied by increasing total cholesterol level than the other groups. This study suggests that carbohydrate is necessary for adequate physical and metabolic performance when lipid-rich diet is loaded.
Assuntos
Desoxiglucose/farmacologia , Dieta com Restrição de Carboidratos/efeitos adversos , Dieta Hiperlipídica/efeitos adversos , Glicólise/efeitos dos fármacos , Animais , Regulação do Apetite/efeitos dos fármacos , Biomarcadores/sangue , Regulação da Temperatura Corporal/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Fatores de Tempo , Redução de Peso/efeitos dos fármacosRESUMO
We investigated the influence of immediate postexercise dietary supplementation on the subsequent food consumption pattern and endurance exercise performance in physically trained individuals. On 2 occasions, trained male cyclists performed a glycogen-depleting exercise bout followed by a 2-h nutritional supplementation period, 28 h of free-living recovery, and a subsequent 40-km cycling time trial. During the 2-h postexercise supplementation, the subjects consumed equal volumes of reduced-fat chocolate milk (CM) or a sports beverage (SB) in a single-blind, randomized design. Thereafter, the cyclists maintained a food log during the free-living recovery period. Dietary and exercise performance parameters were compared between the treatment beverage visits. No differences in total caloric and macronutrient intakes were detected between the CM and SB trials over the course of the free-living recovery. However, a significant interaction (treatment × time) was detected for caloric and macronutrient intakes during the early phase of free-living recovery, such that significantly larger proportions were consumed shortly after SB as compared with CM. No difference was observed in completion time of the 40-km cycling time trial (CM: 66.9 ± 4.1 vs SB: 66.9 ± 3.7 min). Hence, the cyclists achieved similar levels of recovery during the prolonged, free-living period despite the different acute, postexercise nutrient intake rates. We suggest that given adequate time, athletes appear to subconsciously modify their food consumption in response to varied postexercise supplementation such that subsequent-day exercise performance is equivalent.
Assuntos
Ciclismo/fisiologia , Ingestão de Alimentos/fisiologia , Comportamento Alimentar/fisiologia , Glicogênio/metabolismo , Resistência Física/fisiologia , Adulto , Animais , Chocolate , Carboidratos da Dieta , Ingestão de Energia/fisiologia , Humanos , Masculino , Leite , Adulto JovemRESUMO
Increased aortic stiffness, measured by carotid-to-femoral pulse wave velocity (PWV), is an independent predictor of cardiovascular disease, and past data have shown that low-fat and low-energy diets, fed for 8-24 weeks, lower PWV. The purpose of this study was to determine whether a reduction in PWV would be achieved by dietary carbohydrate (CHO) restriction, shown to bring about weight loss over a shorter timeframe. Men (n = 10, age: 41.8 ± 10.2 years, BMI: 34.2 ± 3.0 kg/m2 (mean ± SD)) and women (n = 10, age: 38.6 ± 6.1 years, BMI: 33.5 ± 3.8 kg/m2) with characteristics of insulin resistance and the metabolic syndrome consumed a structured, CHO-restricted diet for 4 weeks (energy deficit, 645 kcal/day). For the whole group, subjects lost 5.4% ± 0.5% (P < 0.001) of body weight and experienced significant reductions in blood pressure (6%-8%), plasma insulin (34%), and triglycerides (34%). PWV was reduced by 6% ± 2% (7.1 ± 0.2 m/s to 6.7 ± 0.2 m/s, P = 0.008) and surprisingly, in women, it fell significantly (from 7.2 ± 0.3 m/s to 6.3 ± 0.3 m/s, P = 0.028), while no changes were observed in men (7.2 ± 0.3 vs. 7.0 ± 0.3 m/s, P = 0.144). This is the first study to demonstrate that weight loss can improve PWV in as little as 4 weeks and that dietary CHO restriction may be an effective treatment for reducing aortic stiffness in women. Future studies are needed to establish the mechanisms by which dietary CHO restriction may confer more cardiovascular benefits to women than to men.
Assuntos
Aorta/fisiologia , Dieta com Restrição de Carboidratos , Sobrepeso , Análise de Onda de Pulso , Redução de Peso/fisiologia , Adulto , Carboidratos da Dieta , Ingestão de Alimentos , Feminino , Humanos , Resistência à Insulina/fisiologia , Masculino , Pessoa de Meia-Idade , Sobrepeso/dietoterapia , Sobrepeso/epidemiologia , Sobrepeso/fisiopatologiaRESUMO
Due to gastrointestinal tract adaptability, the study aimed to determine the impact of gut-training protocol over 2 weeks on gastrointestinal status, blood glucose availability, fuel kinetics, and running performance. Endurance runners (n = 25) performed a gut-challenge trial (GC1), consisting of 2 h running exercise at 60% VÌO2max whilst consuming gel-discs containing 30 g carbohydrates (2:1 glucose/fructose, 10% w/v) every 20 min and a 1 h distance test. Participants were then randomly assigned to a carbohydrate gel-disc (CHO-S), carbohydrate food (CHO-F), or placebo (PLA) gut-training group for 2 weeks of repetitive gut-challenge intervention. Participants then repeated a second gut-challenge trial (GC2). Gastrointestinal symptoms reduced in GC2 on CHO-S (60%; p = 0.008) and CHO-F (63%; p = 0.046); reductions were greater than PLA (p < 0.05). H2 peak was lower in GC2 on CHO-S (mean (CI): 6 (4-8) ppm) compared with CHO-F (9 (6-12) ppm) and PLA (12 (2-21) ppm) (trial × time: p < 0.001). Blood glucose concentration was higher in GC2 on CHO-S (7.2 (6.3-8.1) mmol·L-1) compared with CHO-F (6.1 (5.7-6.5) mmol·L-1) and PLA (6.2 (4.9-7.5) mmol·L-1) (trial × time: p = 0.015). No difference in oxidation rates, plasma I-FABP, and cortisol concentrations were observed between groups and trials. Distance test improved on CHO-S (5.2%) and CHO-F (4.3%) in GC2, but not on PLA (-2.1%) (trial × time: p = 0.009). Two weeks of gut-training with CHO-S and CHO-F improved gastrointestinal symptoms and running performance compared with PLA. CHO-S also reduced malabsorption and increased blood glucose availability during endurance running compared with PLA.
Assuntos
Carboidratos da Dieta/administração & dosagem , Exercício Físico/fisiologia , Glucose/metabolismo , Corrida/fisiologia , Adaptação Fisiológica , Glicemia , Dieta , Análise de Alimentos , Trato Gastrointestinal , Humanos , Masculino , Resistência FísicaRESUMO
Islet transplantation (ITx) is effective in preventing severe hypoglycemia by restoring glucose-dependent insulin secretion in type 1 diabetes (T1D), but may not normalize glucose regulation. Studies suggest that physical activity plays a role in maintaining ß-cell mass and function in individuals with type 2 diabetes and animal models of diabetes. This could indicate that physical activity plays a role in graft survival in ITx recipients. This review's objective is to assess current knowledge related to physical activity in ITx recipients. Responses to other challenges in blood glucose control (i.e., hypoglycemia) in human ITx recipients were examined to provide in-depth background information. To identify studies involving exercise in ITx recipients, a systematic search was performed using PubMed, Medline, and Embase, which revealed 277 English language publications. Publications were excluded if they did not involve ITx recipients; did not involve physical activity or hypoglycemia; or did not report on glucose, insulin, or counterregulatory hormones. During induced hypoglycemia, studies indicate normal suppression of insulin in ITx individuals compared with healthy non-T1D controls. Studies involving exercise in ITx animals have conflicting results, with time since transplantation and transplantation site (spleen, liver, kidney, peritoneal cavity) as possible confounders. No study examining blood glucose responses to physical activity in human ITx recipients was identified. A small number of induced-hypoglycemia studies in humans, and exercise studies in animals, would suggest that glucoregulation is greatly improved yet is still imperfect in this population and that ITx does not fully restore counterregulatory responses to challenges in blood glucose homeostasis.
Assuntos
Diabetes Mellitus Tipo 1/cirurgia , Exercício Físico , Hiperglicemia/prevenção & controle , Hipoglicemia/prevenção & controle , Transplante das Ilhotas Pancreáticas/efeitos adversos , Complicações Pós-Operatórias/prevenção & controle , Transplante Heterotópico/efeitos adversos , Animais , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/complicações , Sobrevivência de Enxerto , Humanos , Hiperglicemia/epidemiologia , Hipoglicemia/epidemiologia , Complicações Pós-Operatórias/epidemiologia , RiscoRESUMO
Overweight, obesity, and poor health is becoming a global concern for defence force personnel. Conventional nutrition guidelines are being questioned for their efficacy in achieving optimal body composition and long-term health. This study compared the effects of a 12-week low-carbohydrate, high-fat diet with a conventional, high-carbohydrate, low-fat diet on weight reduction and metabolic health outcomes in at-risk New Zealand Defence Force personnel. In this randomised controlled trial, 41 overweight personnel were assigned to intervention and control groups. Weight, waist circumference, fasting lipids, and glycaemic control were assessed at baseline and at 12 weeks. Within-group change scores were analysed using the t statistic and interpreted using a p < 0.05 level of statistical significance. Between-group mean differences and confidence intervals were analysed using effect sizes and magnitude-based inferences. Twenty-six participants completed the trial (14 intervention, 12 control). Both groups showed statistically significant weight and waist circumference reductions; the intervention group significantly reduced triglycerides and serum glucose and significantly increased high-density lipoprotein cholesterol (HDLc). Relative to control, the intervention group showed small, possibly to likely beneficial effects for weight, triglycerides, glucose, insulin, and homeostasis model assessment of insulin resistance; moderate, likely beneficial effects for HDL cholesterol, triglyceride:HDLc ratio and HbA1c; and a small, likely harmful effect for low-density lipoprotein cholesterol. This dietary approach shows promise for short-term weight loss and improved metabolic health outcomes conditions compared with mainstream recommendations. It should be offered to defence force personnel at least as a viable alternative means to manage their weight and health.
Assuntos
Dieta com Restrição de Carboidratos , Dieta Hiperlipídica , Militares , Obesidade/dietoterapia , Sobrepeso/dietoterapia , Adulto , Glicemia/metabolismo , Composição Corporal , Índice de Massa Corporal , Colesterol/sangue , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Insulina/sangue , Masculino , Obesidade/metabolismo , Sobrepeso/metabolismo , Triglicerídeos/sangue , Circunferência da Cintura , Redução de PesoRESUMO
The objective of this study was to evaluate differences in calories, nutrient content, overall healthfulness, and use of sweetener ingredients between products with and without sugar claims. Consumers assume products with sugar claims are healthier and lower in calories. It is therefore important claims be found on comparatively healthier items. This study is a cross-sectional analysis of the University of Toronto's 2013 Food Label Database. Subcategories where at least 5% of products (and n ≥ 5) carried a sugar claim were included (n = 3048). Differences in median calorie content, nutrient content, and overall healthfulness, using the Food Standards Australia/New Zealand Nutrient Profiling Scoring criterion, between products with and without sugar claims, were determined. Proportion of products with and without claims that had excess free sugar levels (≥10% of calories from free sugar) and that contained sweeteners was also determined. Almost half (48%) of products with sugar claims contained excess free sugar, and a greater proportion contained sweeteners than products without such claims (30% vs 5%, χ2 = 338.6, p < 0.0001). Overall, products with sugar claims were "healthier" and had lower median calorie, free sugar, total sugar, and sodium contents than products without claims. At the subcategory level, reductions in free sugar contents were not always met with similar reductions in calorie contents. This study highlights concerns with regards to the nutritional composition of products bearing sugar claims. Findings can support educational messaging to assist consumer interpretation of sugar claims and can inform changes in nutrition policies, for example, permitting sugar claims only on products with calorie reductions and without excess free sugar.
Assuntos
Açúcares da Dieta/análise , Rotulagem de Alimentos , Canadá , Estudos Transversais , Dieta Saudável , Análise de Alimentos , Comportamentos Relacionados com a Saúde , Marketing , Valor NutritivoRESUMO
Carbohydrate ingestion at the end of a single exercise is recognized as delaying fatigue and accelerating recovery, but whether chronic ingestion can prevent overtraining during periods of intense training has not yet been elucidated. This study aimed to determine whether carbohydrate supplementation minimizes overtraining in Wistar rats. The animals underwent 11 weeks of training (running) on a treadmill, and the last 3 weeks were designed to induce overtraining. One group was supplemented with carbohydrates (EX-CHO) (n = 13), 1 group had no supplementation (EX) (n = 10), and a third group remained inactive (C) (n = 9). Performance tests were given before training (Pr1) and at the 8th (Pr2) and 11th (Pr3) training week. Food intake, body weight, testosterone, cortisol, malondialdehyde, creatine kinase, and activities of the PI3-K, Akt-1, mTOR, and GSK-3 enzymes were measured. In the EX group, there was a significant 32.6% performance decrease at Pr3 when compared with Pr2. In addition, at protocol completion, the EX-CHO group had a greater gastrocnemius weight than did the C group (p = 0.02), which the EX group did not. Training caused anorexia, decreased testosterone (p = 0.001), and increased malondialdehyde (p = 0.009) in both exercise groups compared with the C group, with no influence of carbohydrate supplementation on these variables (p > 0.05). Compared with in the C group, the activity of Akt-1 was higher in the EX-CHO group but not in the EX group (p = 0.013). Carbohydrate supplementation promoted an attenuation in the performance decrement and maintained gastrocnemius muscle mass in animals that had undergone overtraining protocols, which was accompanied by increased activity of the Akt-1 molecular indicator.
Assuntos
Carboidratos da Dieta/administração & dosagem , Suplementos Nutricionais , Condicionamento Físico Animal/fisiologia , Animais , Peso Corporal , Creatina Quinase/sangue , Quinase 3 da Glicogênio Sintase/sangue , Hidrocortisona/sangue , Masculino , Malondialdeído/sangue , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Resistência Física/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Wistar , Corrida/fisiologia , Testosterona/sangueRESUMO
Carbohydrate ingestion and level of concentric versus eccentric muscle activity may alter exercise-induced health benefits for individuals who have high waist circumference as a metabolic risk factor. The purpose of this study was to determine whether metabolic and inflammation responses to an exercise recovery meal differ between women with lower (Lo-WC, <80 cm) compared with higher (Hi-WC) waist circumference when the exercise is primarily concentric (uphill walking; UPHILL) versus primarily eccentric (downhill walking; DOWNHILL). Recreationally active women (age, 18-39 years; body mass index, 19-35.4 m·kg-2; Lo-WC, n = 13; Hi-WC, n = 10) completed UPHILL, DOWNHILL, and resting (CONTROL) conditions followed 30 min later by a mixed meal tolerance test (MMTT) with carbohydrates to protein ratio of 4:1, and blood glucose, insulin, and inflammation markers were compared across conditions. Compared with Lo-WC, the Hi-WC group had higher (p < 0.05) (i) insulin during the MMTT in CONTROL (mean ± SE; 48.5 ± 8.2 vs 22.9 ± 2.8 pmol·L-1), (ii) baseline (0.7 ± 0.4 vs 2.0 ± 1.7 pg·mL-1) interleukin-6 (IL-6), and (iii) IL-6 responses 8 h after UPHILL and CONTROL. Both groups had (i) increases in IL-6 at 0 h after UPHILL and at 8 h after DOWNHILL, and (ii) lower glycemic responses in UPHILL. Women with Hi-WC had higher IL-6 at rest and delayed increases in IL-6 after a high-carbohydrate meal in all conditions. This is consistent with an inflammation response to the meal and or uphill walking exercise. However, both concentrically and eccentrically biased exercises offered benefits to insulin responses to a high carbohydrate meal for Hi-WC.
Assuntos
Dieta da Carga de Carboidratos/efeitos adversos , Exercício Físico , Comportamento Alimentar , Hiperinsulinismo/prevenção & controle , Resistência à Insulina , Obesidade Abdominal/terapia , Obesidade/terapia , Adolescente , Adulto , Glicemia/análise , Índice de Massa Corporal , Estudos Cross-Over , Feminino , Humanos , Hiperinsulinismo/epidemiologia , Insulina/sangue , Interleucina-6/sangue , Refeições , Montana/epidemiologia , Obesidade/sangue , Obesidade/imunologia , Obesidade/fisiopatologia , Obesidade Abdominal/sangue , Obesidade Abdominal/imunologia , Obesidade Abdominal/fisiopatologia , Fatores de Risco , Circunferência da Cintura , Caminhada , Adulto JovemRESUMO
The inflammation induced by obesogenic diets is associated with deposition of fat in the liver. On the other hand, anti-inflammatory and immunosuppressive therapies may impact in body fat storage and in liver lipid dynamics. It is important to study specific inflammatory mediators in this context, since their role on hepatic damage is not fully clarified. This study aimed to evaluate the role of interleukin (IL)-18 and tumor necrosis factor (TNF) receptor in liver dysfunction induced by diet. Male C57BL/6 wild-type (WT), IL-18, and TNF receptor 1 knockout mice (IL-18-/- and TNFR1-/-) were divided according to the experimental diets: chow diet or a high-refined carbohydrate-containing diet. Alanine aminotransferase was quantified by colorimetric analysis. Total fat content in the liver was determined by Folch methods. Levels of TNF, IL-6, IL-4, and IL-13 in liver samples were measured by ELISA assay. IL-18 and TNFR knockout mice fed with chow diet showed higher liver triglycerides deposition than WT mice fed with the same diet (WT: 131.9 ± 24.5; IL-18-/-: 239.4 ± 38.12*; TNF-/-: 179.6 ± 50.45*; *P < 0.01). Furthermore, these animals also showed a worse liver histopathological score and lower levels of TNF, IL-6, IL-4, and IL-13 in the liver. Interestingly, treatment with a high-carbohydrate diet did not exacerbate liver damage in IL-18-/- and TNFR1-/- mice. Our data suggest that IL-18 and TNF may be involved on hepatic homeostasis mainly in a context of a healthy diet.
Assuntos
Interleucina-18/metabolismo , Metabolismo dos Lipídeos , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral/agonistas , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo , Animais , Biomarcadores/sangue , Biomarcadores/metabolismo , Colágeno/metabolismo , Dieta da Carga de Carboidratos/efeitos adversos , Manipulação de Alimentos , Inflamassomos/metabolismo , Interleucina-13/metabolismo , Interleucina-18/genética , Interleucina-4/metabolismo , Interleucina-6/metabolismo , Fígado/imunologia , Fígado/patologia , Fígado/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/imunologia , Hepatopatia Gordurosa não Alcoólica/patologia , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Triglicerídeos/metabolismoRESUMO
Short-term intake of a high-fat diet aggravates postprandial glucose metabolism; however, the dose-response relationship has not been investigated. We hypothesized that short-term intake of a eucaloric low-carbohydrate/high-fat diet (LCHF) would aggravate postprandial glucose metabolism and circulating adhesion molecules in healthy males. Seven healthy young males (mean ± SE; age: 26 ± 1 years) consumed either a eucaloric control diet (C, approximately 25% fats), a eucaloric intermediate-carbohydrate/intermediate-fat diet (ICIF, approximately 50% fats), or an LCHF (approximately 70% fats) for 3 days. An oral meal tolerance test (MTT) was performed after the 3-day dietary intervention. The concentrations of plasma glucose, insulin, glucagon-like peptide-1 (GLP-1), intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 (VCAM-1) were determined at rest and during MTT. The incremental area under the curve (iAUC) of plasma glucose concentration during MTT was significantly higher in LCHF than in C (P = 0.009). The first-phase insulin secretion indexes were significantly lower in LCHF than in C (P = 0.04). Moreover, the iAUC of GLP-1 and VCAM-1 concentrations was significantly higher in LCHF than in C (P = 0.014 and P = 0.04, respectively). The metabolites from ICIF and C were not significantly different. In conclusion, short-term intake of eucaloric diet containing a high percentage of fats in healthy males excessively increased postprandial glucose and VCAM-1 concentrations and attenuated first-phase insulin release.
Assuntos
Glicemia/metabolismo , Dieta Hiperlipídica , Período Pós-Prandial , Molécula 1 de Adesão de Célula Vascular/sangue , Ácido 3-Hidroxibutírico/sangue , Adulto , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Estudos Cross-Over , Dieta com Restrição de Carboidratos , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Ingestão de Energia , Ácidos Graxos não Esterificados/sangue , Peptídeo 1 Semelhante ao Glucagon/sangue , Humanos , Insulina/sangue , Molécula 1 de Adesão Intercelular/sangue , Masculino , Refeições , Fatores de Tempo , Triglicerídeos/sangueRESUMO
The acute effects of drinks rich in protein (PRO) versus carbohydrate (CHO) on cardiovascular hemodynamics and reactivity are uncertain. A randomized crossover design was used to compare 400-mL isoenergetic (1.1 MJ) drinks containing whey protein (PRO; 44 g) or carbohydrate (CHO; 57 g) versus 400 mL of water in 14 healthy men. The primary and secondary outcomes were changes in cardiac output, blood pressure, systemic vascular resistance (SVR) and digital volume pulse measured prior to and 30 min following consumption at rest, during 12 min of multi-stage bicycle ergometry, and 15 min postexercise. The mean change (95% confidence interval (CI)) in resting cardiac output at 30 min was greater for CHO than for PRO or water: 0.7 (0.4 to 1.0), 0.1 (-0.2 to 0.40), and 0.0 (-0.3 to 0.3) L/min (P < 0.001), respectively; the higher cardiac output following CHO was accompanied by an increase in stroke volume and a lower SVR. The mean increments (95% CI) in cardiac output during exercise were CHO 4.7 (4.4 to 5.0), PRO 4.9 (4.6 to 5.2), and water 4.6 (4.3 to 4.9) L/min with the difference between PRO versus water being significant (P < 0.025). There were no other statistically significant differences. In summary, a CHO-rich drink increased cardiac output and lowered SVR in the resting state compared with a PRO-rich drink or water but the effect size of changes in these variables did not differ during or after exercise between CHO and PRO. Neither protein nor carbohydrate affected blood pressure reactivity to exercise.