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1.
EClinicalMedicine ; 48: 101434, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35706490

RESUMEN

Background: Chronic exposure to high iron levels increases diabetes risk partly by inducing oxidative stress, but the consequences of acute iron administration on beta cells are unknown. We tested whether the acute administration of iron for the correction of iron deficiency influenced insulin secretion and the production of reactive oxygen species. Methods: Single-center, double-blinded, randomized controlled trial conducted between June 2017 and March 2020. 32 women aged 18 to 47 years, displaying symptomatic iron deficiency without anaemia, were recruited from a community setting and randomly allocated (1:1) to a single infusion of 1000 mg intravenous ferric carboxymaltose (iron) or saline (placebo). The primary outcome was the between group mean difference from baseline to day 28 in first and second phase insulin secretion, assessed by a two-step hyperglycaemic clamp. All analyses were performed by intention to treat. This trial was registered in ClinicalTrials.gov NCT03191201. Findings: Iron infusion did not affect first and second phase insulin release. For first phase, the between group mean difference from baseline to day 28 was 0 µU × 10 min/mL [95% CI, -22 to 22, P = 0.99]. For second phase, it was -5 µUx10min/mL [95% CI, -161 to 151; P = 0.95] at the first plateau of the clamp and -249 µUx10min/mL [95% CI, -635 to 137; P = 0.20] at the second plateau. Iron infusion increased serum ascorbyl/ascorbate ratio, a marker of plasma oxidative stress, at day 14, with restoration of normal ratio at day 28 relative to placebo. Finally, high-sensitive C-reactive protein levels remained similar among groups. Interpretation: In iron deficient women without anaemia, intravenous administration of 1000 mg of iron in a single sitting did not impair glucose-induced insulin secretion despite a transient increase in the levels of circulating reactive oxygen species. Funding: The Swiss National Science Foundation, University of Lausanne and Leenaards, Raymond-Berger and Placide Nicod Foundations.

2.
EFSA J ; 20(2): e07074, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35251356

RESUMEN

Following a request from five European Nordic countries, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was tasked to provide scientific advice on a tolerable upper intake level (UL) or a safe level of intake for dietary (total/added/free) sugars based on available data on chronic metabolic diseases, pregnancy-related endpoints and dental caries. Specific sugar types (fructose) and sources of sugars were also addressed. The intake of dietary sugars is a well-established hazard in relation to dental caries in humans. Based on a systematic review of the literature, prospective cohort studies do not support a positive relationship between the intake of dietary sugars, in isocaloric exchange with other macronutrients, and any of the chronic metabolic diseases or pregnancy-related endpoints assessed. Based on randomised control trials on surrogate disease endpoints, there is evidence for a positive and causal relationship between the intake of added/free sugars and risk of some chronic metabolic diseases: The level of certainty is moderate for obesity and dyslipidaemia (> 50-75% probability), low for non-alcoholic fatty liver disease and type 2 diabetes (> 15-50% probability) and very low for hypertension (0-15% probability). Health effects of added vs. free sugars could not be compared. A level of sugars intake at which the risk of dental caries/chronic metabolic diseases is not increased could not be identified over the range of observed intakes, and thus, a UL or a safe level of intake could not be set. Based on available data and related uncertainties, the intake of added and free sugars should be as low as possible in the context of a nutritionally adequate diet. Decreasing the intake of added and free sugars would decrease the intake of total sugars to a similar extent. This opinion can assist EU Member States in setting national goals/recommendations.

3.
J Nutr ; 152(5): 1200-1206, 2022 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-35179211

RESUMEN

Dietary carbohydrates are our main source of energy. Traditionally, they are classified based on the polymer length between simple and complex carbohydrates, which does not necessarily reflect their impact on health. Simple sugars, such as fructose, glucose, and lactose, despite having a similar energy efficiency and caloric content, have very distinct metabolic effects, leading to increased risk for various chronic diseases when consumed in excess. In addition, beyond the absolute amount of carbohydrate consumed, recent data point out that the food form or processing level can modulate both the energy efficiency and the cardiometabolic risk associated with specific carbohydrates. To account for both of these aspects-the quality of carbohydrates as well as its food form-several metrics can be proposed to help identifying carbohydrate-rich food sources and distinguish between those that would favor the development of chronic diseases and those that may contribute to prevent these. This review summarizes the findings presented during the American Society of Nutrition Satellite symposium on carbohydrate quality, in which these different aspects were presented.


Asunto(s)
Carbohidratos de la Dieta , Estado Nutricional , Enfermedad Crónica , Humanos , Estados Unidos
4.
J Nutr ; 151(12): 3661-3670, 2021 12 03.
Artículo en Inglés | MEDLINE | ID: mdl-34510217

RESUMEN

BACKGROUND: Both fructose consumption and chronic stress contribute to the development of metabolic disorders. The consequences of such combination are not fully understood. OBJECTIVE: We investigated whether fructose supplementation and chronic stress synergistically disturb hepatic lipid and glucose metabolism. The role of energy sensing, redox, and inflammatory status during development of metabolic disturbances was investigated. METHODS: Female Wistar rats, aged 2.5 mo, were divided into 4 experimental groups: control (C) fed a standard diet (commercial food and drinking water); fructose (F) fed the same food and 10% fructose solution; stress (S) fed the standard diet and subjected to chronic unpredictable stress and, stress + fructose (SF) combining conditions F and S as above. Stress included daily stressors: cold water forced swimming, physical restraint, cold room, wet bedding, rocking, switching, or tilting cages. After 9 wk, hepatic enzymes and transcription factors involved in gluconeogenesis, lipogenesis, fatty acid oxidation, antioxidative defence, energy sensing, and cytokines were assessed by qPCR, Western blotting, and spectrophotometry and analyzed by 2-factor ANOVA. RESULTS: Fructose increased AMP-activated protein kinase (AMPK) phosphorylation (40%; P < 0.05) and the ratio of inhibitory phosphorylation to total acetyl-CoA carboxylase (46%; P < 0.01), and decreased sterol regulatory element binding protein 1c nuclear translocation by 30% (P < 0.05) in F and SF compared with C rats. Increased phosPck (phoenolpyruvate carboxykinase) (85%) and G6pase(glucose-6-phosphatase) (55%) was observed in S rats (P < 0.05). A 40% decrease in Apob (apolipoprotein B-100) and an increase in hepatic lipids (P < 0.05), together with a double increase in TNF-α (P < 0.001), were observed in S rats, but without liver histopathological changes. These stress effects on lipid accumulation and TNF-α were abolished in SF rats (P < 0.05). CONCLUSIONS: Fructose does not enhance stress effects on hepatic lipid and glucose metabolism but attenuates its effects on hepatic lipid accumulation and inflammation, suggesting that, in female rats, AMPK activation prevails over stress-induced effects.


Asunto(s)
Fructosa , Hígado , Animales , Dieta , Femenino , Fructosa/efectos adversos , Fructosa/metabolismo , Lipogénesis , Hígado/metabolismo , Ratas , Ratas Wistar
5.
Clin Nutr ; 40(6): 3807-3814, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34130027

RESUMEN

INTRODUCTION: Regulation of endogenous glucose production (EGP) is essential for glucose homeostasis. It includes gluconeogenesis (GNG) from non-carbohydrate substrates and hepatic glycogenolysis. Both these pathways are dysregulated in acute stress, but the magnitude of this deregulation cannot be assessed in clinical practice. The study aims at identifying clinically available variables predictive of EGP and GNG magnitude by modeling routinely available data. METHODS: This exploratory study is based on the data from the Supplemental Parenteral Nutrition study 2 (SPN2), which measured EGP and GNG at days 4 and 10 in 23 critically ill patients. The correlation between EGP and GNG and 83 potential clinical indicators were explored, using single-stage and multivariate analysis. RESULTS: On single-stage analysis, the strongest correlations were noradrenaline dose at day 4 with GNG (R = 0.71; P = 0.0004) and Nutrition risk screening score (NRS) with EGP (R = 0.42; P = 0.05). At day 10, VO2 (R = 0.59, P = 0.04) was correlated with GNG and VCO2 with EGP (R = 0.85, P = 0.00003). Cumulated insulin dose between days 5 and 9 was correlated to EGP at day 10 (R = 0.55, P = 0.03). Our multivariate model could predict EGP at day 4 (VCO2, glucose and energy intake) with an error coefficient (e.c.) between 7.8% and 23.4% (minimal and maximal error), and GNG at day 10 (age, mean and basal blood glucose), with an e.c. of 18.5% and 29.9%. GNG at day 4 and EGP at day 10 could not be predicted with an e.c. < 40%. CONCLUSION: This preliminary exploratory study shows that GNG and EGP have different predictors on days 4 and 10; EGP is more correlated with the metabolic level, while GNG is dependent on external factors. Nevertheless, a bundle of variables could be identified to empirically assess the magnitude of both values. Our results suggest that a robust model might be built, but requires a prospective study including a larger number of patients.


Asunto(s)
Glucemia/metabolismo , Enfermedad Crítica , Gluconeogénesis , Glucosa/metabolismo , Modelos Estadísticos , Apoyo Nutricional , Ensayos Clínicos Controlados Aleatorios como Asunto , Anciano , Femenino , Homeostasis , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Índice de Severidad de la Enfermedad
6.
J Hepatol ; 75(1): 46-54, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33684506

RESUMEN

BACKGROUND & AIMS: Excessive fructose intake is associated with increased de novo lipogenesis, blood triglycerides, and hepatic insulin resistance. We aimed to determine whether fructose elicits specific effects on lipid metabolism independently of excessive caloric intake. METHODS: A total of 94 healthy men were studied in this double-blind, randomized trial. They were assigned to daily consumption of sugar-sweetened beverages (SSBs) containing moderate amounts of fructose, sucrose (fructose-glucose disaccharide) or glucose (80 g/day) in addition to their usual diet or SSB abstinence (control group) for 7 weeks. De novo fatty acid (FA) and triglyceride synthesis, lipolysis and plasma free FA (FFA) oxidation were assessed by tracer methodology. RESULTS: Daily intake of beverages sweetened with free fructose and fructose combined with glucose (sucrose) led to a 2-fold increase in basal hepatic fractional secretion rates (FSR) compared to control (median FSR %/day: sucrose 20.8 (p = 0.0015); fructose 19.7 (p = 0.013); control 9.1). Conversely, the same amounts of glucose did not change FSR (median of FSR %/day 11.0 (n.s.)). Fructose intake did not change basal secretion of newly synthesized VLDL-triglyceride, nor did it alter rates of peripheral lipolysis, nor total FA and plasma FFA oxidation. Total energy intake was similar across groups. CONCLUSIONS: Regular consumption of both fructose- and sucrose-sweetened beverages in moderate doses - associated with stable caloric intake - increases hepatic FA synthesis even in a basal state; this effect is not observed after glucose consumption. These findings provide evidence of an adaptative response to regular fructose exposure in the liver. LAY SUMMARY: This study investigated the metabolic effects of daily sugar-sweetened beverage consumption for several weeks in healthy lean men. It revealed that beverages sweetened with the sugars fructose and sucrose (glucose and fructose combined), but not glucose, increase the ability of the liver to produce lipids. This change may pave the way for further unfavorable effects on metabolic health. CLINICAL TRIAL REGISTRATION NUMBER: NCT01733563.


Asunto(s)
Ácidos Grasos/biosíntesis , Fructosa , Glucosa , Lipogénesis , Lipoproteínas VLDL/biosíntesis , Hígado , Sacarosa , Triglicéridos/biosíntesis , Adulto , Método Doble Ciego , Ingestión de Energía , Fructosa/administración & dosificación , Fructosa/efectos adversos , Fructosa/metabolismo , Glucosa/administración & dosificación , Glucosa/metabolismo , Voluntarios Sanos , Humanos , Metabolismo de los Lípidos/efectos de los fármacos , Metabolismo de los Lípidos/fisiología , Lipogénesis/efectos de los fármacos , Lipogénesis/fisiología , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Sacarosa/administración & dosificación , Sacarosa/efectos adversos , Sacarosa/metabolismo , Bebidas Azucaradas , Edulcorantes/farmacología
7.
Clin Nutr ; 40(6): 4246-4254, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33551217

RESUMEN

BACKGROUND & AIMS: Hyperuricemia is an independent risk factor for the metabolic syndrome and cardiovascular disease. We hypothesized that asymptomatic carriers for hereditary fructose intolerance (OMIM 22960) would have increased uric acid and altered component of the metabolic syndrome when exposed to fructose overfeeding. METHODS: Six heterozygotes for HFI (hHFI) and 6 controls (Ctrl) were studied in a randomized, controlled, crossover trial. Participants ingested two identical test meals containing 0.7 g kg-1 glucose and 0.7 g kg-1 fructose according to a cross-over design, once after a 7-day on a low fructose diet (LoFruD, <10 g/d) and on another occasion after 7 days on a high fructose diet (HiFruD, 1.4 g kg-1 day-1 fructose + 0.1 g kg-1 day-1 glucose). Uric acid, glucose, and insulin concentrations were monitored in fasting conditions and over 2 h postprandial, and insulin resistance indexes were calculated. RESULTS: HiFruD increased fasting uric acid (p < 0.05) and reduced fasting insulin sensitivity estimated by the homeostasis model assessment (HOMA) for insulin resistance (p < 0.05), in both groups. Postprandial glucose concentrations were not different between hHFI and Ctrl. However HiFruD increased postprandial plasma uric acid, insulin and hepatic insulin resistance index (HIRI) in hHFI only (all p < 0.05). CONCLUSIONS: Seven days of HiFruD increased fasting uric acid and slightly reduced fasting HOMA index in both groups. In contrast, HiFruD increased postprandial uric acid, insulin concentration and HIRI in hHFI only, suggesting that heterozygosity for pathogenic Aldolase B variants may confer an increased susceptibility to the effects of dietary fructose on uric acid and hepatic insulin sensitivity. This trial was registered at the U.S. Clinical Trials Registry as NCT03545581.


Asunto(s)
Dieta de Carga de Carbohidratos/efectos adversos , Intolerancia a la Fructosa/sangre , Fructosa/efectos adversos , Hiperuricemia/genética , Ácido Úrico/sangre , Adulto , Glucemia/metabolismo , Estudios Cruzados , Dieta de Carga de Carbohidratos/métodos , Ayuno/sangre , Femenino , Fructosa/administración & dosificación , Intolerancia a la Fructosa/genética , Fructosa-Bifosfato Aldolasa/genética , Glucosa/administración & dosificación , Glucosa/efectos adversos , Heterocigoto , Humanos , Hiperuricemia/etiología , Insulina/sangre , Resistencia a la Insulina/genética , Hígado/metabolismo , Masculino , Comidas/fisiología , Síndrome Metabólico/sangre , Síndrome Metabólico/genética , Periodo Posprandial
8.
Clin Nutr ; 40(4): 1691-1698, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33413911

RESUMEN

BACKGROUND &AIMS: Dietary sugars are absorbed in the hepatic portal circulation as glucose, fructose, or galactose. The gut and liver are required to process fructose and galactose into glucose, lactate, and fatty acids. A high sugar intake may favor the development of cardio-metabolic diseases by inducing Insulin resistance and increased concentrations of triglyceride-rich lipoproteins. METHODS: A narrative review of the literature regarding the metabolic effects of fructose-containing sugars. RESULTS: Sugars' metabolic effects differ from those of starch mainly due to the fructose component of sucrose. Fructose is metabolized in a set of fructolytic cells, which comprise small bowel enterocytes, hepatocytes, and kidney proximal tubule cells. Compared to glucose, fructose is readily metabolized in an insulin-independent way, even in subjects with diabetes mellitus, and produces minor increases in glycemia. It can be efficiently used for energy production, including during exercise. Unlike commonly thought, fructose when ingested in small amounts is mainly metabolized to glucose and organic acids in the gut, and this organ may thus shield the liver from potentially deleterious effects. CONCLUSIONS: The metabolic functions of splanchnic organs must be performed with homeostatic constraints to avoid exaggerated blood glucose and lipid concentrations, and thus to prevent cellular damages leading to non-communicable diseases. Excess fructose intake can impair insulin-induced suppression of glucose production, stimulate de novo lipogenesis, and increase intrahepatic and blood triglyceride concentrations. With chronically high fructose intake, enterocyte can switch to lipid synthesis and accumulation of triglyceride, possibly causing an enterocyte dysfunction.


Asunto(s)
Azúcares de la Dieta/metabolismo , Glucosa/metabolismo , Riñón/metabolismo , Metabolismo de los Lípidos , Hígado/metabolismo , Homeostasis , Humanos
10.
Nutrients ; 12(11)2020 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-33198224

RESUMEN

The effects of early-life fructose consumption on hepatic signaling pathways and their relation to the development of metabolic disorders in later life are not fully understood. To investigate whether fructose overconsumption at a young age induces alterations in glucocorticoid signaling that might contribute to development of metabolic disturbances, we analysed glucocorticoid receptor hormone-binding parameters and expression of its target genes involved in gluconeogenesis (phosphoenolpyruvate carboxykinase and glucose-6-phosphatase) and lipid metabolism (lipin-1), as well as redox and inflammatory status in the liver of female rats subjected to a fructose-rich diet immediately after weaning. The fructose diet increased hepatic corticosterone concentration, 11ß-hydroxysteroid dehydrogenase type 1 level, glucocorticoid receptor protein level and hormone-binding activity, as well as lipin-1 level. The expression of glucose-6-phosphatase was reduced in fructose-fed rats, while phosphoenolpyruvate carboxykinase remained unaltered. The fructose-rich diet increased the level of fructose transporter GLUT2, while the expression of fructolytic enzymes fructokinase and aldolase B remained unaltered. The diet also affected pro-inflammatory pathways, but had no effect on the antioxidant defence system. In conclusion, a fructose-rich diet applied immediately after weaning promoted lipogenesis and enhanced hepatic glucocorticoid signaling, possibly to protect against inflammatory damage, but without an effect on gluconeogenesis and antioxidant enzymes. Yet, prolonged treatment might ultimately lead to more pronounced metabolic disturbances.


Asunto(s)
Carbohidratos de la Dieta/efectos adversos , Fructosa/administración & dosificación , Glucocorticoides/metabolismo , Lipogénesis , Receptores de Glucocorticoides/metabolismo , Transducción de Señal/efectos de los fármacos , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/metabolismo , Animales , Corticosterona/metabolismo , Femenino , Hígado/metabolismo , Proteínas Nucleares/metabolismo , Ratas , Ratas Wistar , Triglicéridos/sangre
11.
Mol Nutr Food Res ; 64(13): e1901141, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32379936

RESUMEN

SCOPE: Intake of fructose-sweetened beverages and chronic stress (CS) both increase risk of cardiometabolic diseases. The aim is to investigate whether these factors synergistically perturb lipid metabolism in rat liver and kidney. METHODS AND RESULTS: Fractional de novo lipogenesis (fDNL), intrahepatic- and intrarenal-triglycerides (IHTG and IRTG), de novo palmitate (DNPalm) content, FA composition, VLDL-TGs kinetics, and key metabolic gene expression at the end of the feeding and non-feeding phases in rats exposed to standard chow diet, chow diet + CS, 20% liquid high-fructose supplementation (HFr), or HFr+CS are measured. HFr induces hypertriglyceridemia, up-regulates fructose-metabolism and gluconeogenic enzymes, increases IHTG and DNPalm content in IHTG and IRTG, and augments fDNL at the end of the feeding phase. These changes are diminished after the non-feeding phase. CS does not exert such effects, but when combined with HFr, it reduces IHTG and visceral adiposity, enhances lipogenic gene expression and fDNL, and increases VLDL-DNPalm secretion. CONCLUSION: Liquid high-fructose supplementation increases IHTG and VLDL-TG secretion after the feeding phase, the latter being the result of stimulated hepatic and renal DNL. Chronic stress potentiates the effects of high fructose on fDNL and export of newly synthesized VLDL-TGs, and decreases fructose-induced intrahepatic TG accumulation after the feeding phase.


Asunto(s)
Fructosa/efectos adversos , Riñón/efectos de los fármacos , Lipogénesis , Hígado/metabolismo , Estrés Psicológico/fisiopatología , Animales , Composición Corporal , Ingestión de Alimentos , Ingestión de Energía , Enzimas/genética , Enzimas/metabolismo , Regulación de la Expresión Génica , Gluconeogénesis/efectos de los fármacos , Gluconeogénesis/fisiología , Riñón/metabolismo , Metabolismo de los Lípidos/efectos de los fármacos , Metabolismo de los Lípidos/fisiología , Lipogénesis/efectos de los fármacos , Lipoproteínas VLDL/metabolismo , Hígado/efectos de los fármacos , Masculino , Palmitatos/metabolismo , Ratas Wistar , Triglicéridos/metabolismo
12.
Int J Food Sci Nutr ; 71(3): 286-295, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32279625

RESUMEN

Multiple factors may affect the metabolic fate of carbohydrates. Today, well-standardised and accepted methods may allow for the definitions of the changes in the glucose and insulin curves following the ingestion of either carbohydrate-based and other foods. More debate is still raised on the clinical meaning of these classifications when used at a population level, while emphasis is raised on the approach to carbohydrate metabolism on an individual basis. Within these ranges of applications, other compounds, such as plant polyphenols, may favourably add synergic effects through the modulation of carbohydrate digestion and glucose metabolic steps, resulting in lowering postprandial glucose and insulin levels. Finally, a growing knowledge suggests that the balance of dietary fructose and individual physical activity represent the key point to address the compound towards either positive, energy sparing effects, or a degenerative metabolic burden. The carbohydrate quality within a whole dietary and lifestyle pattern may therefore challenge the individual balance towards health or disease.


Asunto(s)
Carbohidratos de la Dieta/administración & dosificación , Índice Glucémico , Glucemia , Dieta , Fructosa , Humanos , Metabolismo de los Lípidos , Comidas , Ciencias de la Nutrición , Periodo Posprandial , Investigación
13.
Int J Food Sci Nutr ; 71(7): 815-825, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32070154

RESUMEN

Overconsumption of fructose-enriched beverages and everyday stress are involved in the pathogenesis of metabolic disorders through modulation of hepatic glucose metabolism. The aim of the study was to investigate whether interaction of high-fructose diet and chronic stress alter insulin and glucocorticoid signalling thus affecting hepatic glucose homeostasis. High-fructose diet led to hyperinsulinemia, increased glucose transporter 2 level, elevated protein kinase B (Akt) phosphorylation, increased glucokinase mRNA and phospho-to-total glycogen synthase kinase 3 ratio and decreased expression of gluconeogenic genes. Fructose diet also led to stimulated glucocorticoid prereceptor metabolism, but downstream signalling remained unchanged due to increased glucocorticoid clearance. Stress did not affect hepatic insulin and glucocorticoid signalling nor glucose metabolism, while the interaction of the factors was observed only for glucokinase expression. The results suggest that, under conditions of fructose-induced hyperinsulinemia, suppression of gluconeogenesis and glycogen synthase activation contribute to the maintenance of glucose homeostasis. The increased glucocorticoid inactivation may represent an adaptive mechanism to prevent hyperglycaemia.


Asunto(s)
Azúcares de la Dieta/administración & dosificación , Fructosa/administración & dosificación , Glucosa/metabolismo , Homeostasis/efectos de los fármacos , Hígado/efectos de los fármacos , Animales , Relación Dosis-Respuesta a Droga , Regulación de la Expresión Génica/efectos de los fármacos , Glucocorticoides/metabolismo , Insulina/genética , Insulina/metabolismo , Hígado/metabolismo , Masculino , Ratas , Ratas Wistar , Transducción de Señal/efectos de los fármacos , Estrés Fisiológico
14.
Nutr Diabetes ; 10(1): 1, 2020 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-32066654

RESUMEN

BACKGROUND: The mechanisms by which chronic stress increases the risk of non-communicable diseases remain poorly understood. On one hand, chronic stress may increase systemic vascular resistance (SVR) and blood pressure, which may lead to blood vessels injury and altered myocardial perfusion. On the other hand, chronic stress may promote the overconsumption of sugar-containing foods and favor obesity. There is indeed evidence that sweet foods are preferentially consumed to alleviate stress responses. The effects of nutritive and non-nutritive sweeteners (NNS) on hemodynamic stress responses remain however largely unknown. OBJECTIVE/DESIGN: This study aimed at comparing the effects of sucrose-containing and NNS-containing drinks, as compared to unsweetened water, on hemodynamic responses to acute stress in twelve healthy female subjects. Acute stress responses were elicited by a 30-min mental stress (5-min Stroop's test alternated with 5-min mental arithmetic) and a 3-min cold pressure test (CPT), each preceded by a resting baseline period. Hemodynamic stress responses were investigated by the repeated measurement of mean arterial pressure and the continuous monitoring of cardiac output by thoracic electrical bioimpedance measurement. SVR was selected as a primary outcome because it is a sensitive measure of hemodynamic responses to acute stress procedures. RESULTS: With all three drinks, SVR were not changed with mental stress (P = 0.437), but were increased with CPT (P = 0.045). Both mental stress and CPT increased mean arterial pressure and heart rate (all P < 0.001). Cardiac output increased with mental stress (P < 0.001) and remained unchanged with CPT (P = 0.252). No significant differences in hemodynamic responses were observed between water, sucrose and NNS (stress × condition, all P > 0.05). CONCLUSIONS: These results demonstrate that sucrose and NNS do not alter hemodynamic responses to two different standardized acute stress protocols.


Asunto(s)
Sacarosa en la Dieta/administración & dosificación , Hemodinámica/efectos de los fármacos , Edulcorantes no Nutritivos/administración & dosificación , Estrés Psicológico/fisiopatología , Bebidas , Presión Sanguínea/efectos de los fármacos , Estudios Cruzados , Femenino , Estado de Salud , Voluntarios Sanos , Humanos , Edulcorantes Nutritivos/administración & dosificación , Valor Nutritivo , Estrés Fisiológico , Resistencia Vascular/efectos de los fármacos , Adulto Joven
15.
Clin Nutr ESPEN ; 35: 95-102, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31987128

RESUMEN

BACKGROUND & OBJECTIVES: Obesity is often associated with increased postprandial triglyceride (TG) concentrations, mainly from chylomicrons- and VLDL-TG. These alterations are usually reverted to normal after gastric bypass surgery (GB), through mechanisms which remain unknown. The objective of this study was therefore to assess the contribution of exogenous labelled fatty acids ingested with a meal to postprandial blood chylomicrons and VLDL-TG concentrations after GB. SUBJECTS/METHODS: 7 GB patients 3-5 years after surgery (GB: 2M/5F, mean BMI 30 ± 2 kg/m2, mean age 40 ± 3 years), 6 overweight non operated subjects (OW: 1M/5F, mean BMI 31 ± 3 kg/m2, mean age 38 ± 2 years) and 8 normal weight healthy subjects (NW: 4M/4F, mean BMI 22 ± 1 kg/m2, mean age 26 ± 4 years) were studied over 7 h following ingestion of a liquid meal containing 18 g fat labelled with 250 mg 13C16 palmitate, 22 g protein, 36 g fructose and 36 g glucose. TG, 13C palmitate (13C-palm) and apoB48 concentrations were measured hourly in whole plasma and/or in chylomicrons and VLDL lipoprotein sub-fractions. RESULTS: OW subjects had higher chylomicron-than NW (chylo-TG 96.5 (23.1) vs 28.8 (11.8) mmol/l*420min (p = 0.02)), but similar total, chylo-13C-palm and apoB48 iAUCs. In GB, chylo- 13C-palm and apoB48 increased earlier after meal ingestion, but then remained lower than in NW and OW throughout the postprandial period. GB also had lower chylo-TG iAUCs than OW (8.9 (11.5) vs 96.5 (23.2) mmol/l*420min, p = 0.003). Their apoB48 iAUCs were not different from NW and OW (509.2 (90.5) vs 710.2 (80.5) and 870.1 (297.6) pg/ml*420min, all p > 0.05). CONCLUSIONS: An accelerated postprandial apoB48 rise, together with unchanged postprandial apoB48 iUAC, suggests that intestinal fat absorption and chylomicron secretion was quantitatively unaltered, but accelerated after gastric bypass. In contrast, the decreased postprandial chylo-TG and 13C-palm iAUCs suggest that plasma chylomicron clearance was enhanced after gastric bypass.


Asunto(s)
Derivación Gástrica , Lipoproteínas VLDL/sangre , Sobrepeso/sangre , Sobrepeso/cirugía , Periodo Posprandial , Triglicéridos/sangre , Adulto , Apolipoproteína B-48/sangre , Glucemia/metabolismo , Índice de Masa Corporal , Quilomicrones/sangre , Estudios Transversales , Femenino , Fructosa/sangre , Humanos , Insulina/sangre , Masculino , Obesidad/sangre , Adulto Joven
17.
Obes Facts ; 13(1): 1-28, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31945762

RESUMEN

Heterogeneity of interindividual and intraindividual responses to interventions is often observed in randomized, controlled trials for obesity. To address the global epidemic of obesity and move toward more personalized treatment regimens, the global research community must come together to identify factors that may drive these heterogeneous responses to interventions. This project, called OBEDIS (OBEsity Diverse Interventions Sharing - focusing on dietary and other interventions), provides a set of European guidelines for a minimal set of variables to include in future clinical trials on obesity, regardless of the specific endpoints. Broad adoption of these guidelines will enable researchers to harmonize and merge data from multiple intervention studies, allowing stratification of patients according to precise phenotyping criteria which are measured using standardized methods. In this way, studies across Europe may be pooled for better prediction of individuals' responses to an intervention for obesity - ultimately leading to better patient care and improved obesity outcomes.


Asunto(s)
Variación Biológica Poblacional , Testimonio de Experto , Anamnesis/normas , Obesidad/terapia , Ensayos Clínicos Controlados Aleatorios como Asunto/normas , Variación Biológica Poblacional/fisiología , Conducta de Elección , Dieta , Europa (Continente) , Humanos , Obesidad/diagnóstico , Pronóstico , Proyectos de Investigación/normas
18.
Asia Pac J Clin Nutr ; 28(3): 645-663, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31464412

RESUMEN

BACKGROUND AND OBJECTIVES: Rising obesity in Southeast Asia, one consequence of economic growth, has been linked to a rising consumption of energy from added sugars. This symposium, organized by ILSI Southeast Asia, explored regional issues related to dietary sugars and health and identified ways in which these issues could be addressed by regional regulatory agencies, food producers, and the consumer. METHODS AND STUDY DESIGN: Papers on the following topics were presented: 1) current scientific evidence on the effects of sugars and non-caloric sweeteners on body weight, health, and eating behaviors; 2) innovations by food producers to reduce sugar consumption in the region; 3) regional dietary surveillance of sugar consumption and suggestions for consumer guidance. A panel discussion explored effective approaches to promote healthy eating in the region. RESULTS: Excessive consumption of energy in the form of added sugars can have adverse consequences on diet quality, lipid profiles, and health. There is a need for better surveillance of total and added sugars intakes in selected Southeast Asian countries. Among feasible alternatives to corn sweeteners (high fructose corn syrup) and cane sugar are indigenous sweeteners with low glycemic index (e.g., coconut sap sugar). Their health benefits should be examined and regional sugar consumption tracked in detail. Product reformulation to develop palatable lower calorie alternatives that are accepted by consumers continues to be a challenge for industry and regulatory agencies. CONCLUSIONS: Public-private collaborations to develop healthy products and effective communication strategies can facilitate consumer acceptance and adoption of healthier foods.


Asunto(s)
Carbohidratos de la Dieta , Análisis de los Alimentos , Etiquetado de Alimentos , Azúcares , Edulcorantes , Asia , Bebidas , Humanos , Obesidad
19.
PLoS One ; 14(6): e0217751, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31170218

RESUMEN

BACKGROUND AND AIMS: Hepatitis C virus (HCV) infection is associated with insulin resistance, which may lead to type 2 diabetes and its complications. Although HCV infects mainly hepatocytes, it may impair insulin sensitivity at the level of uninfected extrahepatic tissues (muscles and adipose tissue). The aim of this study was to assess whether an interferon-free, antiviral therapy may improve HCV-associated hepatic vs. peripheral insulin sensitivity. METHODS: In a single-arm exploratory trial, 17 non-diabetic, lean chronic hepatitis C patients without significant fibrosis were enrolled, and 12 completed the study. Patients were treated with a combination of sofosbuvir/ledipasvir and ribavirin for 12 weeks, and were submitted to a 2-step euglycemic hyperinsulinemic clamp with tracers, together with indirect calorimetry measurement, to measure insulin sensitivity before and after 6 weeks of antivirals. A panel of 27 metabolically active cytokines was analyzed at baseline and after therapy-induced viral suppression. RESULTS: Clamp analysis performed in 12 patients who achieved complete viral suppression after 6 weeks of therapy showed a significant improvement of the peripheral insulin sensitivity (13.1% [4.6-36.7], p = 0.003), whereas no difference was observed neither in the endogenous glucose production, in lipolysis suppression nor in substrate oxidation. A distinct subset of hepatokines, potentially involved in liver-to-periphery crosstalk, was modified by the antiviral therapy. CONCLUSION: Pharmacological inhibition of HCV improves peripheral (but not hepatic) insulin sensitivity in non-diabetic, lean individuals with chronic hepatitis C without significant fibrosis.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis C Crónica/tratamiento farmacológico , Resistencia a la Insulina , Delgadez/complicaciones , Adulto , Citocinas/sangre , Diabetes Mellitus/patología , Femenino , Glucosa/metabolismo , Hepatitis C Crónica/sangre , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
20.
J Physiol ; 597(14): 3561-3571, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31116420

RESUMEN

Fructose metabolism is generally held to occur essentially in cells of the small bowel, the liver, and the kidneys expressing fructolytic enzymes (fructokinase, aldolase B and a triokinase). In these cells, fructose uptake and fructolysis are unregulated processes, resulting in the generation of intracellular triose phosphates proportionate to fructose intake. Triose phosphates are then processed into lactate, glucose and fatty acids to serve as metabolic substrates in other cells of the body. With small oral loads, fructose is mainly metabolized in the small bowel, while with larger loads fructose reaches the portal circulation and is largely extracted by the liver. A small portion, however, escapes liver extraction and is metabolized either in the kidneys or in other tissues through yet unspecified pathways. In sedentary subjects, consumption of a fructose-rich diet for several days stimulates hepatic de novo lipogenesis, increases intrahepatic fat and blood triglyceride concentrations, and impairs insulin effects on hepatic glucose production. All these effects can be prevented when high fructose intake is associated with increased levels of physical activity. There is also evidence that, during exercise, fructose carbons are efficiently transferred to skeletal muscle as glucose and lactate to be used for energy production. Glucose and lactate formed from fructose can also contribute to the re-synthesis of muscle glycogen after exercise. We therefore propose that the deleterious health effects of fructose are tightly related to an imbalance between fructose energy intake on one hand, and whole-body energy output related to a low physical activity on the other hand.


Asunto(s)
Ingestión de Energía/fisiología , Metabolismo Energético/fisiología , Ejercicio Físico/fisiología , Fructosa/metabolismo , Animales , Glucosa/metabolismo , Glucógeno/metabolismo , Humanos , Ácido Láctico/metabolismo , Lipogénesis/fisiología , Hígado/metabolismo , Músculo Esquelético/metabolismo
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