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1.
Nutrients ; 13(3)2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33652807

RESUMO

Overconsumption of sugar-sweetened beverages increases risk factors associated with cardiometabolic disease, in part due to hepatic fructose overload. However, it is not clear whether consumption of beverages containing fructose as naturally occurring sugar produces equivalent metabolic dysregulation as beverages containing added sugars. We compared the effects of consuming naturally-sweetened orange juice (OJ) or sucrose-sweetened beverages (sucrose-SB) for two weeks on risk factors for cardiometabolic disease. Healthy, overweight women (n = 20) were assigned to consume either 3 servings of 100% orange juice or sucrose-SB/day. We conducted 16-hour serial blood collections and 3-h oral glucose tolerance tests during a 30-h inpatient visit at baseline and after the 2-week diet intervention. The 16-h area under the curve (AUC) for uric acid increased in subjects consuming sucrose-SB compared with subjects consuming OJ. Unlike sucrose-SB, OJ did not significantly increase fasting or postprandial lipoproteins. Consumption of both beverages resulted in reductions in the Matsuda insulin sensitivity index (OJ: -0.40 ± 0.18, p = 0.04 within group; sucrose-SB: -1.0 ± 0.38, p = 0.006 within group; p = 0.53 between groups). Findings from this pilot study suggest that consumption of OJ at levels above the current dietary guidelines for sugar intake does not increase plasma uric acid concentrations compared with sucrose-SB, but appears to lead to comparable decreases of insulin sensitivity.


Assuntos
Citrus sinensis , Sucos de Frutas e Vegetais , Sobrepeso/sangue , Sacarose/análise , Bebidas Adoçadas com Açúcar , Adulto , Área Sob a Curva , Índice de Massa Corporal , Feminino , Humanos , Resistência à Insulina , Lipoproteínas/sangue , Síndrome Metabólica/etiologia , Síndrome Metabólica/prevenção & controle , Sobrepeso/complicações , Sobrepeso/terapia , Projetos Piloto , Período Pós-Prandial/fisiologia , Ácido Úrico/sangue
2.
Nutrients ; 13(2)2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33572918

RESUMO

In this study, we compared the metabolic properties of the Asian staples rice and noodles, which are typically high in glycaemic index (GI), to two types of spaghetti. It is hypothesised that pasta can be a healthy replacement, particularly amongst the Asian population. Thirty Chinese and Indian subjects (17 men, 13 women; BMI: 18.5-25 kg/m2) participated in this randomised crossover trial. On seven occasions, they consumed a glucose reference drink (3 times), white rice, wheat-based mee pok noodles, semolina spaghetti and wholegrain spaghetti. Blood samples were taken to measure glucose and insulin response over a period of 3 h. The current evaluation showed that semolina spaghetti and wholegrain spaghetti can be classified as low GI products, with a GI of 53 and 54, respectively, significantly lower than wheat based mee pok noodles (74) and rice (80) (p < 0.005). In addition, both spaghettis had a lower insulin response compared to rice (p < 0.05). Furthermore, there was no difference in glucose or insulin response between semolina and wholegrain spaghetti. After controlling for gender, ethnicity, fat and fat free mass (kg), the glucose and insulin results did not change. In conclusion, wheat-based pasta can be helpful to modify the carbohydrate-rich Asian diet. Notably, there was no effect of gender, ethnicity and body composition on the glycaemic and insulinaemic response. We speculate that the starch-protein structure as a result of the spaghetti production process is a major driver of its favourable metabolic properties.


Assuntos
Dieta/etnologia , Ingestão de Alimentos/fisiologia , Grão Comestível/metabolismo , Índice Glicêmico/fisiologia , Período Pós-Prandial/fisiologia , Adulto , Grupo com Ancestrais do Continente Asiático/etnologia , Glicemia/metabolismo , China , Estudos Cross-Over , Ingestão de Alimentos/etnologia , Grupo com Ancestrais do Continente Europeu/etnologia , Feminino , Farinha/análise , Voluntários Saudáveis , Humanos , Índia , Insulina/sangue , Masculino , Oryza , Triticum/metabolismo , Grãos Integrais/metabolismo , Adulto Jovem
3.
Nutrients ; 13(2)2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33567505

RESUMO

Scope: To identify a metabolomic profile related to postprandial satiety sensations involved in appetite control would help for a better understanding of the regulation of food intake. Methods and Results: A cross-sectional analysis of plasma metabolites was conducted over 151 overweight/obese adults from the "Satiety Innovation"-SATIN study, a randomized clinical trial of a 12-week weight-loss maintenance period. Postprandial satiety sensations (3 h-iAUC) were assessed by visual analogue scale (VAS) at the beginning and at the end of the study. Fasting plasma metabolites were profiled using a targeted multiplatform metabolomics approach before each appetite test meal. Associations between 124 metabolites and iAUC-satiety were assessed using elastic net linear regression analyses. The accuracy of the multimetabolite weighted models for iAUC-VAS was evaluated using a 10-fold cross-validation (CV) approach and the Pearson's correlation coefficients were estimated. Five and three metabolites were selected in the first and the second assessments, respectively. Circulating glycine and linoleic acid concentrations were consistently and positively associated with higher iAUC-satiety in both visits. Sucrose and sphingomyelins (C32:2, C38:1) were negatively associated with iAUC-satiety in the first visit. The Pearson correlations coefficients between the metabolomic profiles and iAUC-satiety in the first and the second appetite assessments were 0.37 and 0.27, respectively. Conclusion: Higher glycine and linoleic acid were moderately but consistently associated with higher postprandial satiety in two different appetite assessments in overweight and obese subjects.


Assuntos
Regulação do Apetite/fisiologia , Obesidade/sangue , Sobrepeso/sangue , Período Pós-Prandial/fisiologia , Saciação/fisiologia , Adulto , Idoso , Área Sob a Curva , Estudos Transversais , Método Duplo-Cego , Jejum/sangue , Feminino , Glicina/sangue , Humanos , Modelos Lineares , Ácido Linoleico/sangue , Masculino , Metaboloma , Pessoa de Meia-Idade , Fosfatidilcolinas/sangue , Ensaios Clínicos Controlados Aleatórios como Assunto , Esfingomielinas/sangue , Sacarose/sangue , Escala Visual Analógica , Adulto Jovem
4.
Nutrients ; 13(2)2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33567590

RESUMO

Maternal metabolism and intrauterine conditions influence development of health and disease in offspring, leading to metabolic, physiologic, and/or epigenetic adaptation of the fetus. Maternal gestational diabetes (GDM) leads to higher incidence of obesity and type 2 diabetes in offspring. We have previously shown that fetuses of insulin-resistant mothers with GDM have a delayed reaction to auditory stimuli in the postprandial state, indicating a fetal central insulin resistance. We tested whether this effect could be influenced by a lifestyle intervention in mothers with GDM, including diet counselling and regular blood glucose measurements. We measured fetal brain activity over the course of a maternal glucose challenge, at two measurement time points (baseline at an average of 29 weeks of gestation and follow-up after 4 weeks) in mothers with GDM and mothers with normal glucose tolerance (NGT). Data from eight mothers were able to be included. Fetuses of GDM mothers showed longer latencies than those of NGT mothers postprandially at both measurement time points during the third trimester and did not show a difference in response patterns between baseline and after 4 weeks. Maternal postprandial blood glucose and insulin values did not change from baseline to follow-up either. While the overall intervention seems to have been effective, it does not appear to have influenced the fetal postprandial brain responses. This might have been because interventions for GDM take place relatively late in pregnancy. Future research should focus on maternal lifestyle interventions as early as possible during gestation, or even prenatally.


Assuntos
Encéfalo/embriologia , Diabetes Gestacional/terapia , Feto/fisiopatologia , Terceiro Trimestre da Gravidez , Cuidado Pré-Natal/métodos , Adulto , Glicemia/metabolismo , Estudos de Coortes , Diabetes Gestacional/sangue , Feminino , Feto/embriologia , Idade Gestacional , Ganho de Peso na Gestação , Teste de Tolerância a Glucose , Humanos , Insulina/sangue , Resistência à Insulina/fisiologia , Estilo de Vida , Período Pós-Prandial/fisiologia , Gravidez
5.
Nutrients ; 13(1)2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33419065

RESUMO

Glucose levels in blood must be constantly maintained within a tight physiological range to sustain anabolism. Insulin regulates glucose homeostasis via its effects on glucose production from the liver and kidneys and glucose disposal in peripheral tissues (mainly skeletal muscle). Blood levels of glucose are regulated simultaneously by insulin-mediated rates of glucose production from the liver (and kidneys) and removal from muscle; adipose tissue is a key partner in this scenario, providing nonesterified fatty acids (NEFA) as an alternative fuel for skeletal muscle and liver when blood glucose levels are depleted. During sleep at night, the gradual development of insulin resistance, due to growth hormone and cortisol surges, ensures that blood glucose levels will be maintained within normal levels by: (a) switching from glucose to NEFA oxidation in muscle; (b) modulating glucose production from the liver/kidneys. After meals, several mechanisms (sequence/composition of meals, gastric emptying/intestinal glucose absorption, gastrointestinal hormones, hyperglycemia mass action effects, insulin/glucagon secretion/action, de novo lipogenesis and glucose disposal) operate in concert for optimal regulation of postprandial glucose fluctuations. The contribution of the liver in postprandial glucose homeostasis is critical. The liver is preferentially used to dispose over 50% of the ingested glucose and restrict the acute increases of glucose and insulin in the bloodstream after meals, thus protecting the circulation and tissues from the adverse effects of marked hyperglycemia and hyperinsulinemia.


Assuntos
Glicemia/metabolismo , Glucose/metabolismo , Insulina/metabolismo , Período Pós-Prandial/fisiologia , Tecido Adiposo/metabolismo , Jejum , Ácidos Graxos não Esterificados/sangue , Esvaziamento Gástrico , Homeostase , Humanos , Hiperglicemia/metabolismo , Hiperinsulinismo , Hipoglicemia , Incretinas/sangue , Insulina/sangue , Resistência à Insulina , Rim/metabolismo , Fígado/metabolismo , Refeições , Músculo Esquelético/metabolismo
6.
Postgrad Med ; 133(3): 253-264, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33315495

RESUMO

While A1C is the standard diagnostic test for evaluating long-term glucose management, additional glucose data, either from fingerstick blood glucose testing, or more recently, continuous glucose monitoring (CGM), is necessary for safe and effective management of diabetes, especially for individuals treated with insulin. CGM technology and retrospective pattern-based management using various CGM reports have the potential to improve glycemic management beyond what is possible with fingerstick blood glucose monitoring. CGM software can provide valuable retrospective data on Time-in-Ranges (above, below, within) metrics, the Ambulatory Glucose Profile (AGP), overlay reports, and daily views for persons with diabetes and their healthcare providers. This data can aid in glycemic pattern identification and evaluation of the impact of lifestyle factors on these patterns. Time-in-Ranges data provide an easy-to-define metric that can facilitate goal setting discussions between clinicians and persons with diabetes to improve glycemic management and can empower persons with diabetes in self-management between clinic consultation visits. Here we discuss multiple real-life scenarios from a primary care clinic for the application of CGM in persons with diabetes. Optimizing the use of the reports generated by CGM software, with attention to time in range, time below range, and postprandial glucose-induced time above range, can improve the safety and efficacy of ongoing glucose management.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus/sangue , Hemoglobina A Glicada/análise , Monitorização Ambulatorial/métodos , Período Pós-Prandial/fisiologia , Atenção Primária à Saúde/organização & administração , Automonitorização da Glicemia , Humanos
7.
Am J Clin Nutr ; 112(4): 1114-1119, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32766882

RESUMO

BACKGROUND: High postprandial glucose excursions may increase risk for disease. Individuals have widely varying glucose responses to different meals, and precision nutrition approaches often seek to personalize diets to minimize postprandial glycemic responses as measured by continuous glucose monitors (CGMs). However, it is unknown whether different CGM devices result in concordant meal rankings according to postprandial glycemic excursions. OBJECTIVE: We explored whether meal rankings according to postprandial glycemic excursions differ between 2 simultaneously worn CGMs. METHODS: We collected 27,489 simultaneous measurements from Dexcom G4 Platinum and Abbott Freestyle Libre Pro CGMs during 28 inpatient days in 16 adults without diabetes. Simultaneous glucose measurements obtained for 2 h following 760 ad libitum meals were used to compare within-subject meal rankings between the CGM devices according to their incremental glucose response. RESULTS: Postprandial responses to ad libitum meals were highly variable, with the Abbott and Dexcom systems resulting in within-subject incremental mean ± SD glucose CVs of 91.7 ± 1.9% and 94.2 ± 2.7%, respectively. Within-subject meal rankings for incremental glycemic responses were relatively discordant between CGMs, with a mean Kendall rank correlation coefficient of 0.43 ± 0.05. Meals in the bottom compared with those in the top half of incremental glycemic responses ranked by Abbott resulted in 50 ± 10% (P = 0.0002) less glycemic reduction as measured by Dexcom, and vice versa. The missing glycemic reduction by eating meals ranked according to the discordant CGM was inversely correlated with each subject's Kendall rank correlation coefficient (r = -0.95; P < 0.0001). CONCLUSIONS: Precision nutrition approaches that use CGMs to personalize meal recommendations for minimizing glycemic excursions may be premature given the discordance of within-subject meal rankings between simultaneous CGM devices. More research is needed to clarify the source of this imprecision. This trial was registered at clinicaltrials.gov as NCT03407053.


Assuntos
Glicemia/análise , Estado Nutricional , Período Pós-Prandial/fisiologia , Medicina de Precisão , Adulto , Feminino , Humanos , Masculino , Refeições , Ciências da Nutrição
8.
Am J Clin Nutr ; 112(4): 1002-1014, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32672338

RESUMO

BACKGROUND: It has been suggested that low-energy sweeteners (LES) may be associated with an increased risk of metabolic diseases, possibly due to stimulation of glucose-responsive mechanisms. OBJECTIVE: We conducted a systematic review and meta-analysis of human intervention studies examining the acute effect of LES intake on postprandial glucose (PPG) and postprandial insulin (PPI) responses, in order to comprehensively and objectively quantify these relations. METHODS: We systematically searched the Medline, OVID FSTA, and SCOPUS databases until January 2020. Randomized controlled trials comparing acute postprandial effects on PPG and/or PPI after exposure to LES, either alone, with a meal, or with other nutrient-containing preloads to the same intervention without LES were eligible for inclusion. PPG and PPI responses were calculated as mean incremental area under the curve divided by time. Meta-analyses were performed using random effects models with inverse variance weighing. RESULTS: Twenty-six papers (34 PPG trials and 29 PPI trials) were included. There were no reports of statistically significant differences in the effects of LES on PPG and PPI responses compared with control interventions. Pooled effects of LES intake on the mean change difference in PPG and PPI were -0.02 mmol/L (95% CI: -0.09, 0.05) and -2.39 pmol/L (95% CI: -11.83, 7.05), respectively. The results did not appreciably differ by the type or dose of LES consumed, cointervention type, or fasting glucose and insulin levels. Among patients with type 2 diabetes, the mean change difference indicated a smaller PPG response after exposure to LES compared with the control (-0.3 mmol/L; 95% CI: -0.53, -0.07). CONCLUSIONS: Ingestion of LES, administered alone or in combination with a nutrient-containing preload, has no acute effects on the mean change in postprandial glycemic or insulinemic responses compared with a control intervention. Apart from a small beneficial effect on PPG (-0.3 mmol/L) in studies enrolling patients with type 2 diabetes, the effects did not differ by type or dose of LES, or fasting glucose or insulin levels. This review and meta-analysis was registered at PROSPERO as CRD42018099608.


Assuntos
Glicemia/análise , Insulina/sangue , Período Pós-Prandial/fisiologia , Edulcorantes/farmacologia , Diabetes Mellitus Tipo 2/metabolismo , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
9.
PLoS One ; 15(6): e0233364, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32530969

RESUMO

Type 2 diabetes mellitus (T2DM) is among the most prevalent diseases in the world, affecting over 420 million people. The disease is marked by a poor metabolic effect of insulin leading to chronic hyperglycaemia, which can result in microvascular complications. It is widely known that postprandial glycaemia is reliant on the total carbohydrate content of a meal. However, the importance of the amount and the source of these carbohydrates remains controversial due to mechanisms other than insulin secretion. Oxidative stress, inflammation, pyruvate production and the quality of the intestinal microbiota, resulting in plasma lipopolysaccharides and short-chain fatty acids production, play an important role in blood sugar control and consequently in type 2 diabetes. Thus, we systematically reviewed the preclinical evidences on the impact of the amount and type of carbohydrate found in different diets and its influence on blood glucose levels in diabetic animals. We used a comprehensive and structured search in biomedical databases Medline (PubMed), Scopus and Web of Science, recovering and analyzing 27 original studies. Results showed that sucrose-rich diets deteriorated diabetic condition in animal models regardless of the total dietary carbohydrate content. On the other hand, fiber, particularly resistant starch, improved blood glucose parameters through direct and indirect mechanisms, such as delayed gastric emptying and improved gut microbiota. All studies used rodents as animal models and male animals were preferred over females. Improvements in T2DM parameters in animal models were more closely related to the type of dietary carbohydrate than to its content on a diet, i. e., resistant starch seems to be the most beneficial source for maintaining normoglycemia. Results show that current literature is at high risk of bias due to neglecting experimental methods.


Assuntos
Diabetes Mellitus Tipo 2/dietoterapia , Carboidratos da Dieta/análise , Animais , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/metabolismo , Dieta/métodos , Carboidratos da Dieta/metabolismo , Fibras na Dieta/metabolismo , Sacarose na Dieta/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Insulina/metabolismo , Secreção de Insulina/efeitos dos fármacos , Masculino , Período Pós-Prandial/fisiologia , Triglicerídeos/sangue
10.
Clin Sci (Lond) ; 134(9): 1081-1094, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32352510

RESUMO

The relationship between disturbances in glucose homeostasis and heart failure (HF) progression is bidirectional. However, the mechanisms by which HF intrinsically impairs glucose homeostasis remain unknown. The present study tested the hypothesis that the bioavailability of intact glucagon-like peptide-1 (GLP-1) is affected in HF, possibly contributing to disturbed glucose homeostasis. Serum concentrations of total and intact GLP-1 and insulin were measured after an overnight fast and 15 min after the ingestion of a mixed breakfast meal in 49 non-diabetic patients with severe HF and 40 healthy control subjects. Similarly, fasting and postprandial serum concentrations of these hormones were determined in sham-operated rats, and rats with HF treated with an inhibitor of the GLP-1-degrading enzyme dipeptidyl peptidase-4 (DPP4), vildagliptin, or vehicle for 4 weeks. We found that HF patients displayed a much lower increase in postprandial intact and total GLP-1 levels than controls. The increase in postprandial intact GLP-1 in HF patients correlated negatively with serum brain natriuretic peptide levels and DPP4 activity and positively with the glomerular filtration rate. Likewise, the postprandial increases in both intact and total GLP-1 were blunted in HF rats and were restored by DPP4 inhibition. Additionally, vehicle-treated HF rats displayed glucose intolerance and hyperinsulinemia, whereas normal glucose homeostasis was observed in vildagliptin-treated HF rats. We conclude that the postprandial increase in GLP-1 is blunted in non-diabetic HF. Impaired GLP-1 bioavailability after meal intake correlates with poor prognostic factors and may contribute to the establishment of a vicious cycle between glucose disturbance and HF development and progression.


Assuntos
Glicemia/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Insuficiência Cardíaca/etiologia , Período Pós-Prandial/fisiologia , Idoso , Animais , Peptídeo C/sangue , Feminino , Intolerância à Glucose/fisiopatologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Insulina/sangue , Masculino , Pessoa de Meia-Idade , Obesidade/metabolismo , Obesidade/fisiopatologia , Fragmentos de Peptídeos/sangue , Ratos Wistar
11.
Br J Nutr ; 124(4): 407-417, 2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32248846

RESUMO

This study investigated metabolic, endocrine, appetite and mood responses to a maximal eating occasion in fourteen men (mean: age 28 (sd 5) years, body mass 77·2 (sd 6·6) kg and BMI 24·2 (sd 2·2) kg/m2) who completed two trials in a randomised crossover design. On each occasion, participants ate a homogenous mixed-macronutrient meal (pizza). On one occasion, they ate until 'comfortably full' (ad libitum) and on the other, until they 'could not eat another bite' (maximal). Mean energy intake was double in the maximal (13 024 (95 % CI 10 964, 15 084) kJ; 3113 (95 % CI 2620, 3605) kcal) compared with the ad libitum trial (6627 (95 % CI 5708, 7547) kJ; 1584 (95 % CI 1364, 1804) kcal). Serum insulin incremental AUC (iAUC) increased approximately 1·5-fold in the maximal compared with ad libitum trial (mean: ad libitum 43·8 (95 % CI 28·3, 59·3) nmol/l × 240 min and maximal 67·7 (95 % CI 47·0, 88·5) nmol/l × 240 min, P < 0·01), but glucose iAUC did not differ between trials (ad libitum 94·3 (95 % CI 30·3, 158·2) mmol/l × 240 min and maximal 126·5 (95 % CI 76·9, 176·0) mmol/l × 240 min, P = 0·19). TAG iAUC was approximately 1·5-fold greater in the maximal v. ad libitum trial (ad libitum 98·6 (95 % CI 69·9, 127·2) mmol/l × 240 min and maximal 146·4 (95 % CI 88·6, 204·1) mmol/l × 240 min, P < 0·01). Total glucagon-like peptide-1, glucose-dependent insulinotropic peptide and peptide tyrosine-tyrosine iAUC were greater in the maximal compared with ad libitum trial (P < 0·05). Total ghrelin concentrations decreased to a similar extent, but AUC was slightly lower in the maximal v. ad libitum trial (P = 0·02). There were marked differences on appetite and mood between trials, most notably maximal eating caused a prolonged increase in lethargy. Healthy men have the capacity to eat twice the energy content required to achieve comfortable fullness at a single meal. Postprandial glycaemia is well regulated following initial overeating, with elevated postprandial insulinaemia probably contributing.


Assuntos
Afeto/fisiologia , Apetite/fisiologia , Hiperfagia/sangue , Refeições/fisiologia , Período Pós-Prandial/fisiologia , Adulto , Área Sob a Curva , Glicemia/análise , Índice de Massa Corporal , Estudos Cross-Over , Dipeptídeos/sangue , Ingestão de Energia/fisiologia , Polipeptídeo Inibidor Gástrico/sangue , Grelina/sangue , Peptídeo 1 Semelhante ao Glucagon/sangue , Humanos , Insulina/sangue , Masculino , Adulto Jovem
12.
Nutrients ; 12(4)2020 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-32252402

RESUMO

Food ingestion induces a metered response of the digestive system. Initially, the upper digestive system reacts to process and extract meal substrates. Later, meal residues not absorbed in the small bowel, pass into the colon and activate the metabolism of resident microbiota. Food consumption also induces sensations that arise before ingestion (e.g., anticipatory reward), during ingestion (e.g., gustation), and most importantly, after the meal (i.e., the postprandial experience). The postprandial experience involves homeostatic sensations (satiety, fullness) with a hedonic dimension (digestive well-being, mood). The factors that determine the postprandial experience are poorly understood, despite their potential role in personalized diets and healthy eating habits. Current data suggest that the characteristics of the meal (amount, palatability, composition), the activity of the digestive system (suited processing), and the receptivity of the eater (influenced by multiple conditioning factors) may be important in this context.


Assuntos
Digestão/fisiologia , Ingestão de Alimentos/fisiologia , Microbioma Gastrointestinal/fisiologia , Período Pós-Prandial/fisiologia , Afeto/fisiologia , Comportamento Alimentar , Humanos , Saciação/fisiologia , Resposta de Saciedade
13.
J Sports Med Phys Fitness ; 60(5): 764-769, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32162504

RESUMO

BACKGROUND: Previous reports indicate that postprandial glucose (PPG) responses to exercise may depend on cardiorespiratory fitness (CRF), such that less fit individuals have greater reductions in PPG with exercise. Our aim was to investigate moderating effects of CRF on PPG response following exercise of progressively shorter durations and sedentary rest. METHODS: Thirty-four participants (14 female) completed a 75-g oral glucose tolerance test (OGTT) at seated rest. On three subsequent visits, participants completed additional OGTT with either 1, 3, or 10 minutes of stair-climbing. Fingerstick blood glucose measurements were taken every 15 minutes for 1 hour. CRF was determined using a treadmill ramp test. RESULTS: There was a main effect of condition F(3, 93)=13.07, P<0.001, ηp2=0.30. Stair-climbing reduced PPG iAUC compared to control by -3±27% (P=0.546), -11±29% (P=0.091), and -28±22% (P<0.000) for the 1, 3 and 10 min bouts, respectively. There was no trial by CRF interaction for glucose iAUC F(2.4, 73.8)=0.69, P=0.532, ηp2=0.02. Linear mixed model regression analysis revealed that CRF was not significantly associated with glucose iAUC, b=-14 (-45, 16), P=0.339. CONCLUSIONS: Contrary to previous reports CRF did not moderate PPG responses for either sedentary or exercise conditions in healthy men and women. Short, single-bout stair stepping exercise at a self-selected pace is equally efficient for all fitness levels.


Assuntos
Glicemia/metabolismo , Aptidão Cardiorrespiratória/fisiologia , Exercício Físico/fisiologia , Adulto , Estudos de Casos e Controles , Teste de Esforço/métodos , Feminino , Teste de Tolerância a Glucose , Humanos , Masculino , Período Pós-Prandial/fisiologia , Fatores de Tempo , Adulto Jovem
14.
J Clin Endocrinol Metab ; 105(3)2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-32073608

RESUMO

BACKGROUND: The question of whether there is daytime time variation in diet-induced thermogenesis (DIT) has not been clearly answered. Moreover, it is unclear whether a potential diurnal variation in DIT is preserved during hypocaloric nutrition. OBJECTIVE: We hypothesized that DIT varies depending on the time of day and explored whether this physiological regulation is preserved after low-calorie compared with high-calorie intake. DESIGN: Under blinded conditions, 16 normal-weight men twice underwent a 3-day in-laboratory, randomized, crossover study. Volunteers consumed a predetermined low-calorie breakfast (11% of individual daily kilocalorie requirement) and high-calorie dinner (69%) in one condition and vice versa in the other. DIT was measured by indirect calorimetry, parameters of glucose metabolism were determined, and hunger and appetite for sweets were rated on a scale. RESULTS: Identical calorie consumption led to a 2.5-times higher DIT increase in the morning than in the evening after high-calorie and low-calorie meals (P < .001). The food-induced increase of blood glucose and insulin concentrations was diminished after breakfast compared with dinner (P < .001). Low-calorie breakfast increased feelings of hunger (P < .001), specifically appetite for sweets (P = .007), in the course of the day. CONCLUSIONS: DIT is clearly higher in the morning than in the evening, irrespective of the consumed calorie amount; that is, this physiological rhythmicity is preserved during hypocaloric nutrition. Extensive breakfasting should therefore be preferred over large dinner meals to prevent obesity and high blood glucose peaks even under conditions of a hypocaloric diet.


Assuntos
Restrição Calórica/efeitos adversos , Dieta/efeitos adversos , Refeições/fisiologia , Período Pós-Prandial/fisiologia , Termogênese/fisiologia , Adulto , Apetite/fisiologia , Glicemia/metabolismo , Desjejum/fisiologia , Restrição Calórica/métodos , Calorimetria Indireta , Estudos Cross-Over , Dieta/métodos , Método Duplo-Cego , Ingestão de Energia , Metabolismo Energético , Humanos , Insulina/sangue , Masculino , Fatores de Tempo
15.
Nature ; 579(7800): 575-580, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32050257

RESUMO

The intestinal mucosa serves both as a conduit for the uptake of food-derived nutrients and microbiome-derived metabolites, and as a barrier that prevents tissue invasion by microorganisms and tempers inflammatory responses to the myriad contents of the lumen. How the intestine coordinates physiological and immune responses to food consumption to optimize nutrient uptake while maintaining barrier functions remains unclear. Here we show in mice how a gut neuronal signal triggered by food intake is integrated with intestinal antimicrobial and metabolic responses that are controlled by type-3 innate lymphoid cells (ILC3)1-3. Food consumption rapidly activates a population of enteric neurons that express vasoactive intestinal peptide (VIP)4. Projections of VIP-producing neurons (VIPergic neurons) in the lamina propria are in close proximity to clusters of ILC3 that selectively express VIP receptor type 2 (VIPR2; also known as VPAC2). Production of interleukin (IL)-22 by ILC3, which is upregulated by the presence of commensal microorganisms such as segmented filamentous bacteria5-7, is inhibited upon engagement of VIPR2. As a consequence, levels of antimicrobial peptide derived from epithelial cells are reduced but the expression of lipid-binding proteins and transporters is increased8. During food consumption, the activation of VIPergic neurons thus enhances the growth of segmented filamentous bacteria associated with the epithelium, and increases lipid absorption. Our results reveal a feeding- and circadian-regulated dynamic neuroimmune circuit in the intestine that promotes a trade-off between innate immune protection mediated by IL-22 and the efficiency of nutrient absorption. Modulation of this pathway may therefore be effective for enhancing resistance to enteropathogens2,3,9 and for the treatment of metabolic diseases.


Assuntos
Ingestão de Alimentos/fisiologia , Imunidade Inata/imunologia , Absorção Intestinal/fisiologia , Intestinos/imunologia , Intestinos/fisiologia , Linfócitos/imunologia , Neurônios/metabolismo , Peptídeo Intestinal Vasoativo/metabolismo , Animais , Ritmo Circadiano/fisiologia , Ingestão de Alimentos/imunologia , Feminino , Interleucinas/biossíntese , Interleucinas/imunologia , Absorção Intestinal/imunologia , Intestinos/citologia , Intestinos/microbiologia , Linfócitos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Período Pós-Prandial/fisiologia , Receptores CCR6/metabolismo , Receptores Tipo II de Peptídeo Intestinal Vasoativo/metabolismo , Simbiose
16.
J Nutr ; 150(5): 1303-1312, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32040591

RESUMO

BACKGROUND: Metabolic endotoxemia is considered a cause for high-fat diet (HFD)-induced inflammation. However, convincing experimental evidence in humans is scant. OBJECTIVE: We determined whether a HFD or moderately HFD increases LPS and LPS-mediated cytokine production in the postprandial blood (PPB). METHODS: Ninety-eight volunteers (age: 37.3 ± 1.5 y) from the cross-sectional phenotyping study (PS) and 62 volunteers (age: 26.8 ± 1.2 y) from the intervention study (IS) consumed a breakfast containing 60% kcal fat (HF) and 36% kcal fat (moderately HF), respectively. For the IS, only the results from the placebo group are presented. Blood samples were probed for LPS-mediated cytokine production by incubating them with LPS inhibitor polymyxin B (PMB) for 24 h at 37°C besides the Limulus amebocyte lysate (LAL) assay. Repeated-measures ANOVA was used to compare the temporal changes of metabolic profiles and treatment outcomes. RESULTS: At least 87.5% of the plasma LPS measurements in 32 PS volunteers from each time point were below the LAL assay sensitivity (0.002 EU/mL). PMB suppressed IL-1ß (P = 0.035) and IL-6 (P = 0.0487) production in the 3 h PPB of the PS after 24 h incubation at 37°C compared to the vehicle control, suggesting the presence of LPS. However, the amount of LPS did not increase the cytokine concentrations in the 3 h PPB above the fasting concentrations. Such suppression was not detected in the PPB of the IS. Treating whole blood with lipoprotein lipase (LPL) significantly (P < 0.05) increased FFA and cytokine (IL-1ß, IL-6, TNF-α) concentrations in both studies. CONCLUSION: LPS may not be the major cause of postprandial inflammation in healthy adults consuming a moderately HF meal (36% kcal fat, similar to the typical American diet) or a HF meal (60% kcal fat). Plasma FFAs may modulate postprandial inflammation. The prevailing concept of HFD-induced metabolic endotoxemia requires careful re-evaluation. The PS was registered at clinicaltrials.gov as NCT02367287 and the IS as NCT02472171.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Inflamação/sangue , Inflamação/etiologia , Lipopolissacarídeos/sangue , Período Pós-Prandial/fisiologia , Adulto , Desjejum , Estudos Transversais , Citocinas/sangue , Método Duplo-Cego , Ácidos Graxos não Esterificados/sangue , Feminino , Humanos , Lipopolissacarídeos/antagonistas & inibidores , Lipase Lipoproteica/metabolismo , Masculino , Placebos , Polimixina B/farmacologia
17.
PLoS One ; 15(2): e0229495, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32101585

RESUMO

PURPOSE: "Quantile-dependent expressivity" describes an effect of the genotype that depends upon the level of the phenotype (e.g., whether a subject's triglycerides are high or low relative to its population distribution). Prior analyses suggest that the effect of a genetic risk score (GRS) on fasting plasma triglyceride levels increases with the percentile of the triglyceride distribution. Postprandial lipemia is well suited for testing quantile-dependent expressivity because it exposes each individual's genotype to substantial increases in their plasma triglyceride concentrations. Ninety-seven published papers were identified that plotted mean triglyceride response vs. time and genotype, which were converted into quantitative data. Separately, for each published graph, standard least-squares regression analysis was used to compare the genotype differences at time t (dependent variable) to average triglyceride concentrations at time t (independent variable) to assess whether the genetic effect size increased in association with higher triglyceride concentrations and whether the phenomenon could explain purported genetic interactions with sex, diet, disease, BMI, and drugs. RESULTS: Consistent with the phenomenon, genetic effect sizes increased (P≤0.05) with increasing triglyceride concentrations for polymorphisms associated with ABCA1, ANGPTL4, APOA1, APOA2, APOA4, APOA5, APOB, APOC3, APOE, CETP, FABP2, FATP6, GALNT2, GCKR, HL, IL1b, LEPR, LOX-1, LPL, MC4R, MTTP, NPY, SORT1, SULF2, TNFA, TCF7L2, and TM6SF2. The effect size for these polymorphisms showed a progressively increasing dose-response, with intermediate effect sizes at intermediate triglyceride concentrations. Quantile-dependent expressivity provided an alternative interpretation to their interactions with sex, drugs, disease, diet, and age, which have been traditionally ascribed to gene-environment interactions and genetic predictors of drug efficacy (i.e., personalized medicine). CONCLUSION: Quantile-dependent expressivity applies to the majority of genetic variants affecting postprandial triglycerides, which may arise because the impaired functionalities of these variants increase at higher triglyceride concentrations. Purported gene-drug interactions may be the manifestations of quantile-dependent expressivity, rather than genetic predictors of drug efficacy.


Assuntos
Hiperlipidemias/genética , Hiperlipidemias/metabolismo , Período Pós-Prandial/fisiologia , Adulto , Apolipoproteína C-III/genética , Apolipoproteínas A/genética , HDL-Colesterol/sangue , Feminino , Genótipo , Humanos , Hiperlipidemias/fisiopatologia , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Fenótipo , Polimorfismo de Nucleotídeo Único , Período Pós-Prandial/genética , Análise de Regressão , Triglicerídeos/análise , Triglicerídeos/sangue
18.
Med Sci Sports Exerc ; 52(6): 1385-1393, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31895295

RESUMO

PURPOSE: To identify predictors of favorable changes to postprandial insulin and glucose levels in response to interrupting prolonged sitting time with standing or light-intensity physical activity. METHODS: Data were combined from four similarly designed randomized acute cross-over trials (n = 129; body mass index [BMI] range, 19.6-44.6 kg·m; South Asian = 31.0%; dysglycemia = 27.1%). Treatments included: prolonged sitting (6.5 h) or prolonged sitting broken-up with either standing or light-intensity physical activity (5 min every 30 min). Time-averaged postprandial responses for insulin and glucose were calculated for each treatment (mean ± 95% confidence interval). Mutually adjusted interaction terms were used to examine whether anthropometric (BMI), demographic (age, sex, ethnicity [white European vs South Asian]) and a cardiometabolic variable (Homeostatic Model Assessment of Insulin Resistance)-modified responses. RESULTS: Postprandial insulin and glucose were reduced when individuals interrupted prolonged sitting with bouts of light physical activity, but not with standing. Reductions in time-averaged postprandial insulin were more pronounced if individuals were South Asian compared with white European (-18.9 mU·L [-23.5%] vs -8.2 mU·L [-9.3%]), female compared with male (-15.0 mU·L [-21.2%] vs -12.1 mU·L [-17.6%]) or had a BMI ≥27.2 kg·m (-20.9 mU·L [-22.9%] vs -8.7 mU·L [-18.2%]). Similarly, being female (-0.4 mmol·L [-0.6 mmol·L, -0.2 mmol·L], -6.8% vs -0.1 mmol·L [-0.3 mmol·L, 1 mmol·L], -1.7%) or having a BMI ≥27.2 kg·m (-0.4 mmol·L [-0.6 mmol·L, -0.2 mmol·L], -6.7% vs -0.2 mmol·L [-0.4 mmol·L, 0.0 mmol·L], -3.4%) modified the postprandial glucose response. No significant interactions were found for Homeostatic Model Assessment of Insulin Resistance or age. CONCLUSIONS: Being female, South Asian, or having a higher BMI, all predicted greater reductions in postprandial insulin, whereas being female and having a higher BMI predicted greater reductions in postprandial glucose when sitting was interrupted with light physical activity. These results could help to guide personalized interventions in high-risk participants for whom breaking prolonged sitting time with light activity may yield the greatest therapeutic potential.


Assuntos
Glicemia/metabolismo , Exercício Físico/fisiologia , Insulina/sangue , Período Pós-Prandial/fisiologia , Comportamento Sedentário , Postura Sentada , Posição Ortostática , Grupo com Ancestrais do Continente Asiático , Índice de Massa Corporal , Metabolismo Energético , Grupo com Ancestrais do Continente Europeu , Humanos , Comportamento Sedentário/etnologia , Fatores Sexuais , Reino Unido
19.
Diabetes Res Clin Pract ; 159: 107951, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31790715

RESUMO

AIMS: Gastric emptying is a major determinant of postprandial glycaemia in both health and type 2 diabetes (T2DM); the potential impact of ethnicity on gastric emptying is unclear. We compared the rate of gastric emptying of a standardised meal and the associated glycaemic response in Han Chinese and Caucasian patients with T2DM. METHODS: 14 Han Chinese and 14 Caucasian T2DM patients, managed by diet and/or metformin monotherapy, underwent concurrent measurements of gastric emptying and blood glucose for 240 min after a 99mTc-calcium phytate-labelled mashed potato meal. RESULTS: Han Chinese patients were slightly younger (P < 0.05), and had a lower BMI (P < 0.05), than Caucasians. There were no differences in either HbA1c or fasting blood glucose between them. Gastric half-emptying time (T50) was shorter (P < 0.05) and the postprandial blood glucose increment greater (P < 0.05) in Han Chinese than Caucasian patients. Both the increment in blood glucose from baseline at 60 min and peak blood glucose were related inversely to T50 (P < 0.05 each). CONCLUSIONS: Han Chinese with relatively well-controlled T2DM have more rapid gastric emptying compared to Caucasians, which is associated with a greater postprandial glycaemic excursion. These differences may inform the choice of management, e.g. Han Chinese may particularly benefit from therapies that slow gastric emptying.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Esvaziamento Gástrico/fisiologia , Período Pós-Prandial/fisiologia , Adolescente , Adulto , Criança , Feminino , Disparidades em Assistência à Saúde , Humanos , Masculino , Adulto Jovem
20.
Med Sci Sports Exerc ; 52(3): 720-728, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31652237

RESUMO

INTRODUCTION: This study examines the role of nutritional status during exercise training in patients with type 2 diabetes mellitus by investigating the effect of endurance-type exercise training in the fasted versus the fed state on clinical outcome measures, glycemic control, and skeletal muscle characteristics in male type 2 diabetes patients. METHODS: Twenty-five male patients (glycated hemoglobin (HbA1c), 57 ± 3 mmol·mol (7.4% ± 0.3%)) participated in a randomized 12-wk supervised endurance-type exercise intervention, with exercise being performed in an overnight-fasted state (n = 13) or after consuming breakfast (n = 12). Patients were evaluated for glycemic control, blood lipid profiles, body composition and physical fitness, and skeletal muscle gene expression. RESULTS: Exercise training was well tolerated without any incident of hypoglycemia. Exercise training significantly decreased whole-body fat mass (-1.6 kg) and increased high-density lipoprotein concentrations (+2 mg·dL), physical fitness (+1.7 mL·min·kg), and fat oxidation during exercise in both groups (PTIME < 0.05), with no between-group differences (PTIME × GROUP > 0.05). HbA1c concentrations significantly decreased after exercise training (PTIME < 0.001), with a significant greater reduction after consuming breakfast (-0.30% ± 0.06%) compared with fasted state (-0.08% ± 0.06%; mean difference, 0.21%; PTIME × GROUP = 0.016). No interaction effects were observed for skeletal muscle genes related to lipid metabolism or oxidative capacity. CONCLUSIONS: Endurance-type exercise training in the fasted or fed state do not differ in their efficacy to reduce fat mass, increase fat oxidation capacity, and increase cardiorespiratory fitness and high-density lipoprotein concentrations or their risk of hypoglycemia in male patients with type 2 diabetes. HbA1c seems to be improved more with exercise performed in the postprandial compared with the postabsorptive state.


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Diabetes Mellitus Tipo 2/terapia , Terapia por Exercício , Estado Nutricional/fisiologia , Resistência Física/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Glicemia/metabolismo , Índice de Massa Corporal , Desjejum , Aptidão Cardiorrespiratória/fisiologia , HDL-Colesterol/sangue , Diabetes Mellitus Tipo 2/sangue , Metabolismo Energético/fisiologia , Terapia por Exercício/efeitos adversos , Jejum/fisiologia , Expressão Gênica , Hemoglobina A Glicada/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Período Pós-Prandial/fisiologia , RNA Mensageiro/genética , Perda de Peso
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