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1.
Front Microbiol ; 14: 1207837, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37476669

RESUMO

Introduction: The present study investigates whether supplementation with pectin-type polysaccharides has potential to improve aging-associated dysbiosis of the gut microbiota. The influence of different types of pectins on the gut microbiota composition and short-chain fatty acids (SCFAs) profiles of elderly was compared to younger adults. Methods: Pectins studied included a pectin polysaccharide (PEC), a partially hydrolyzed pectin (PPH), and a pectin oligosaccharide (POS). Additionally, inulin was used as a reference prebiotic substrate. Individual fecal samples were collected from healthy elderly volunteers (70-75 years) and younger adults (30-35 years). In vitro fermentations were performed using the CoMiniGut model with controlled temperature and pH. Samples were withdrawn at baseline and after 24 h fermentation for measurement of SCFAs production and microbiota composition by 16S rRNA gene sequencing. Results and Discussion: The results showed that fermentations with PEC and PPH resulted in a specific stimulation of Faecalibacterium prausnitzii regardless of the age groups. Collinsella aerofaciens became a dominating species in the young adult group with fermentations of all three pectins, which was not observed in the elderly group. No significant differences in SCFAs production were found among the pectins, indicating a high level of functional redundancy. Pectins boosted various bacterial groups differently from the reference prebiotic substrate (inulin). We also found inulin had reduced butyrogenic and bifidogenic effects in the elderly group compared to the younger adult group. In conclusion, the in vitro modulating effects of pectins on elderly gut microbiota showed potential of using pectins to improve age-related dysbiosis.

2.
Nutrients ; 14(17)2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36079886

RESUMO

Pectin is a dietary fiber, and its health effects have been described extensively. Although there are limited clinical studies, there is a growing body of evidence from in vitro studies investigating the effect of pectin on human gut microbiota. This comprehensive review summarizes the findings of gut microbiota modulation in vitro as assessed by 16S rRNA gene-based technologies and elucidates the potential structure-activity relationships. Generally, pectic substrates are slowly but completely fermented, with a greater production of acetate compared with other fibers. Their fermentation, either directly or by cross-feeding interactions, results in the increased abundances of gut bacterial communities such as the family of Ruminococcaceae, the Bacteroides and Lachnospira genera, and species such as Lachnospira eligens and Faecalibacterium prausnitzii, where the specific stimulation of Lachnospira and L. eligens is unique to pectic substrates. Furthermore, the degree of methyl esterification, the homogalacturonan-to-rhamnogalacturonan ratio, and the molecular weight are the most influential structural factors on the gut microbiota. The latter particularly influences the growth of Bifidobacterium spp. The prebiotic potential of pectin targeting specific gut bacteria beneficial for human health and well-being still needs to be confirmed in humans, including the relationship between its structural features and activity.


Assuntos
Microbioma Gastrointestinal , Bactérias , Clostridiales/metabolismo , Fezes/microbiologia , Fermentação , Microbioma Gastrointestinal/fisiologia , Humanos , Pectinas/química , Prebióticos/análise , RNA Ribossômico 16S/genética
3.
Adv Nutr ; 11(5): 1221-1236, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32449931

RESUMO

There is considerable interest in dietary and other approaches to maintaining blood glucose concentrations within the normal range and minimizing exposure to postprandial hyperglycemic excursions. The accepted marker to evaluate the sustained maintenance of normal blood glucose concentrations is glycated hemoglobin A1c (HbA1c). However, although this is used in clinical practice to monitor glycemic control in patients with diabetes, it has a number of drawbacks as a marker of efficacy of dietary interventions that might beneficially affect glycemic control in people without diabetes. Other markers that reflect shorter-term glycemic exposures have been studied and proposed, but consensus on the use and relevance of these markers is lacking. We have carried out a systematic search for studies that have tested the responsiveness of 6 possible alternatives to HbA1c as markers of sustained variation in glycemic exposures and thus their potential applicability for use in dietary intervention trials in subjects without diabetes: 1,5-anhydroglucitol (1,5-AG), dicarbonyl stress, fructosamine, glycated albumin (GA), advanced glycated end products (AGEs), and metabolomic profiles. The results suggest that GA may be the most promising for this purpose, but values may be confounded by effects of fat mass. 1,5-AG and fructosamine are probably not sensitive enough to the range of variation in glycemic exposures observed in healthy individuals. Use of measures based on dicarbonyls, AGEs, or metabolomic profiles would require further research into possible specific molecular species of interest. At present, none of the markers considered here is sufficiently validated and sensitive for routine use in substantiating the effects of sustained variation in dietary glycemic exposures in people without diabetes.


Assuntos
Glicemia , Diabetes Mellitus , Biomarcadores , Desoxiglucose , Frutosamina , Hemoglobinas Glicadas/análise , Humanos
4.
Nutrients ; 11(1)2019 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-30621208

RESUMO

The aim of this systematic review and meta-analysis was to assess the effects of ß-fructan supplementation on bowel function in healthy volunteers and patients. The search process was based on the selection of publications listed in the Pubmed and EUPMC database until December 2017, plus two unpublished studies, to identify studies evaluating the impact of ß-fructans on bowel movement and stool parameters. Forty-seven publications were selected for inclusion. Primary parameter was frequency of bowel movements, evaluated by the number of defecations per day during the study period. Secondary outcomes were stool consistency, stool dry and wet weights, and transit time. Short-chain (DP < 10) ß-fructans contributed to increased stool frequency (0.36 defecation +/- 0.06 per day; p < 0.001), while no significant effect was reported with long-chain (DP ≥ 10) ß-fructans (-0.03 +/- 0.11, p = 0.82). A minimal increase in stool wet weight was also statistically demonstrated with short-chain ß-fructans. Moreover, the meta-analysis highlighted significant differences in stool consistency in contrast to fecal dry weight after ß-fructan supplementation. This systematic review and meta-analysis indicates that short-chain ß-fructan supplementation has a positive effect on bowel function by significantly increasing the frequency of bowel movements.


Assuntos
Fibras na Dieta/administração & dosagem , Frutanos/administração & dosagem , Intestinos/efeitos dos fármacos , Intestinos/fisiologia , Constipação Intestinal/dietoterapia , Constipação Intestinal/prevenção & controle , Defecação/efeitos dos fármacos , Suplementos Nutricionais , Fezes , Trânsito Gastrointestinal , Humanos , Prebióticos/administração & dosagem
5.
FASEB J ; 33(1): 301-313, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29975568

RESUMO

Perinatal nutrition programs physiologic and metabolic functions, with consequences on the susceptibility to develop metabolic diseases in adulthood. The microbiota represents a key factor of such programming. We investigated whether perinatal prebiotic [short-chain fructooligosaccharides (scFOS)] supplementation improved adult metabolic health in association with microbiota changes in pigs used as human model. Sows were supplemented with scFOS or not during the end of gestation and the entire lactation, and offspring received scFOS accordingly during 1 mo after weaning. Pigs were then fed a standard diet for 5 mo, followed by a high-fat diet for 3 mo once adults. Perinatal scFOS supplementation induced a persistent modulation of the composition of the fecal microbiota in adulthood, notably by increasing the Prevotella genus. Meanwhile, scFOS animals displayed improved capacity to secrete glucagon-like peptide-1 and improved pancreas sensitivity to glucose without any changes in peripheral insulin sensitivity. Perinatal scFOS supplementation also increased ileal secretory IgA secretion and alkaline phosphatase activity and decreased TNF-α expression in adipose tissue. In conclusion, perinatal scFOS supplementation induced long-lasting modulation of intestinal microbiota and had beneficial consequences on the host physiology in adulthood. Our results highlight the key role of perinatal nutrition on later microbiota and host metabolic adaptation to an unbalanced diet.-Le Bourgot, C., Ferret-Bernard, S., Apper, E., Taminiau, B., Cahu, A., Le Normand, L., Respondek, F., Le Huërou-Luron, I., Blat, S. Perinatal short-chain fructooligosaccharides program intestinal microbiota and improve enteroinsular axis function and inflammatory status in high-fat diet-fed adult pigs.


Assuntos
Ração Animal/análise , Dieta Hiperlipídica/efeitos adversos , Microbioma Gastrointestinal/efeitos dos fármacos , Inflamação/veterinária , Enteropatias/veterinária , Oligossacarídeos/administração & dosagem , Doenças dos Suínos/prevenção & controle , Fenômenos Fisiológicos da Nutrição Animal , Animais , Animais Recém-Nascidos , Suplementos Nutricionais , Fezes/microbiologia , Feminino , Glucose/metabolismo , Teste de Tolerância a Glucose , Inflamação/tratamento farmacológico , Inflamação/etiologia , Insulina/metabolismo , Enteropatias/tratamento farmacológico , Enteropatias/etiologia , Gravidez , Suínos , Doenças dos Suínos/etiologia
6.
Sci Rep ; 8(1): 9433, 2018 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-29930401

RESUMO

In recent years, lactose-free and low-lactose infant formulas have been increasingly used. The impact of using different carbohydrates than lactose on later cognition of formula-fed infants remains, however, unknown. We examined the effects of providing formulas containing either digestible maltodextrin or lactose as main carbohydrate source (28% of total nutrient composition) on cognitive performance of piglets. Piglets received the formulas from 1 to 9 weeks of age and, starting at 12 weeks, were individually tested in a spatial holeboard task (n = 8 pens/formula), in which they had to learn and memorize a configuration of baited buckets. After 28 acquisition trials, piglets were subjected to 16 reversal trials in which the location of the baited buckets was changed. Piglets fed the maltodextrin-based formula had higher reference memory (RM) scores than piglets fed the lactose-based formula towards the end of acquisition. During the switch of configuration, piglets offered the maltodextrin-based formula tended to have higher RM scores and make fewer RM errors than piglets offered the lactose-based formula. Working (short-term) memory was not affected by the formulas. Compared to lactose, the use of maltodextrin in milk formulas improved long-term spatial memory of piglets, even weeks after the end of the intervention.


Assuntos
Cognição/efeitos dos fármacos , Alimentos Formulados/efeitos adversos , Lactose/farmacologia , Substitutos do Leite/química , Polissacarídeos/farmacologia , Comportamento Espacial/efeitos dos fármacos , Animais , Feminino , Lactose/análise , Masculino , Memória de Longo Prazo/efeitos dos fármacos , Substitutos do Leite/farmacologia , Polissacarídeos/análise , Suínos
7.
Nutr Metab (Lond) ; 15: 9, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29416552

RESUMO

The aim of this systematic review was to assess the effect of fructo-oligosaccharide supplementation on glucose homeostasis. The search process was based on the selection of publications listed in the Pubmed-Medline database until April 2016 to identify studies evaluating the impact of short-chain fructo-oligosaccharides or oligofructose on glucose homeostasis. Twenty-nine trials were included in the systematic review and the meta-analysis was performed on twelve of these papers according to the inclusion criteria. Fasting blood concentrations of glucose and insulin were selected as pertinent criteria of glucose homeostasis for the meta-analysis. The consumption of fructo-oligosaccharides decreased fasting blood glycaemia levels, whatever the metabolic status (healthy, obese or diabetic) and diet (low-fat or high-fat) throughout the experiment. This reduction was linear with prebiotic dose (from 0 to 13% of the feed). Fasting insulinaemia also decreased linearly with fructo-oligosaccharide supplementation but the reduction was only significant in rodents fed a low-fat diet. Potential underlying mechanisms include gut bacterial fermentation of fructo-oligosaccharides to short-chain fatty acids (SCFA) and bacterial modulation of bile acids, both interacting with host metabolism. This systemic review, followed by the meta-analysis, provides evidence that fructo-oligosaccharide supplementation has a significant effect on glucose homeostasis whatever the health status and diet consumed by animals.

8.
Br J Nutr ; 117(1): 83-92, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28115029

RESUMO

Prebiotic supplementation modulates immune system development and function. However, less is known about the effects of maternal prebiotic consumption on offspring intestinal defences and immune system responsiveness. We investigated the effects of maternal short-chain fructo-oligosaccharide (scFOS) supplementation on mucin-secreting cells, ileal secretory IgA and cytokine secretion of weaned offspring and their humoral response to an oral vaccine against obligate intracellular Lawsonia intracellularis. Sows were fed a control diet (CTRL) or scFOS-supplemented diet during the last third of gestation and throughout lactation. At weaning, each litter was divided into two groups receiving a post-weaning CTRL or scFOS diet for a month. Pigs from the four groups were either non-vaccinated (n 16) or vaccinated (n 117) at day 33. Biomarkers related to intestinal defences and immune parameters were analysed 3 weeks later. SCFA production was assessed over time in suckling and weaned pigs. Maternal scFOS supplementation improved ileal cytokine secretions (interferon (IFN)-γ, P<0·05; IL-4, P=0·07) and tended to increase caecal goblet cell number (P=0·06). It increased IgA vaccine response in the serum (P<0·01) and ileal mucosa (P=0·08). Higher bacterial fermentative activity was observed during lactation (total faecal SCFA, P<0·001) and after weaning (colonic butyrate, P=0·10) in pigs from scFOS-supplemented mothers. No synergistic effect between maternal and post-weaning scFOS supplementation was observed. Therefore, maternal scFOS supplementation has long-lasting consequences by strengthening gut defences and immune response to a vaccine against an intestinal obligate intracellular pathogen. Prebiotic consumption by gestating and lactating mothers is decisive in modulating offspring intestinal immunity.


Assuntos
Vacinas Bacterianas/imunologia , Butiratos/sangue , Citocinas/metabolismo , Células Caliciformes/fisiologia , Lawsonia (Bactéria) , Oligossacarídeos/administração & dosagem , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Citocinas/genética , Infecções por Desulfovibrionaceae/microbiologia , Infecções por Desulfovibrionaceae/veterinária , Dieta/veterinária , Suplementos Nutricionais , Feminino , Fenômenos Fisiológicos da Nutrição Materna , Oligossacarídeos/química , Prebióticos , Suínos , Doenças dos Suínos/prevenção & controle
9.
J Nutr ; 146(9): 1651-9, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27440260

RESUMO

BACKGROUND: Muscle mass maintenance is largely regulated by basal muscle protein synthesis and the capacity to stimulate muscle protein synthesis after food intake. The postprandial muscle protein synthetic response is modulated by the amount, source, and type of protein consumed. It has been suggested that plant-based proteins are less potent in stimulating postprandial muscle protein synthesis than animal-derived proteins. However, few data support this contention. OBJECTIVE: We aimed to assess postprandial plasma amino acid concentrations and muscle protein synthesis rates after the ingestion of a substantial 35-g bolus of wheat protein hydrolysate compared with casein and whey protein. METHODS: Sixty healthy older men [mean ± SEM age: 71 ± 1 y; body mass index (in kg/m(2)): 25.3 ± 0.3] received a primed continuous infusion of l-[ring-(13)C6]-phenylalanine and ingested 35 g wheat protein (n = 12), 35 g wheat protein hydrolysate (WPH-35; n = 12), 35 g micellar casein (MCas-35; n = 12), 35 g whey protein (Whey-35; n = 12), or 60 g wheat protein hydrolysate (WPH-60; n = 12). Plasma and muscle samples were collected at regular intervals. RESULTS: The postprandial increase in plasma essential amino acid concentrations was greater after ingesting Whey-35 (2.23 ± 0.07 mM) than after MCas-35 (1.53 ± 0.08 mM) and WPH-35 (1.50 ± 0.04 mM) (P < 0.01). Myofibrillar protein synthesis rates increased after ingesting MCas-35 (P < 0.01) and were higher after ingesting MCas-35 (0.050% ± 0.005%/h) than after WPH-35 (0.032% ± 0.004%/h) (P = 0.03). The postprandial increase in plasma leucine concentrations was greater after ingesting Whey-35 than after WPH-60 (peak value: 580 ± 18 compared with 378 ± 10 µM, respectively; P < 0.01), despite similar leucine contents (4.4 g leucine). Nevertheless, the ingestion of WPH-60 increased myofibrillar protein synthesis rates above basal rates (0.049% ± 0.007%/h; P = 0.02). CONCLUSIONS: The myofibrillar protein synthetic response to the ingestion of 35 g casein is greater than after an equal amount of wheat protein. Ingesting a larger amount of wheat protein (i.e., 60 g) substantially increases myofibrillar protein synthesis rates in healthy older men. This trial was registered at clinicaltrials.gov as NCT01952639.


Assuntos
Proteínas Musculares/biossíntese , Músculo Esquelético/metabolismo , Proteínas de Plantas/administração & dosagem , Triticum/química , Idoso , Idoso de 80 Anos ou mais , Aminoácidos Essenciais/sangue , Glicemia/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Índice de Massa Corporal , Peso Corporal , Caseínas/administração & dosagem , Dieta , Método Duplo-Cego , Exercício Físico , Humanos , Leucina/sangue , Masculino , Miofibrilas/metabolismo , Fenilalanina/administração & dosagem , Período Pós-Prandial , Biossíntese de Proteínas , Hidrolisados de Proteína/administração & dosagem , Proteínas do Soro do Leite/administração & dosagem
10.
PLoS One ; 9(9): e107508, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25238157

RESUMO

Peripartum nutrition is crucial for developing the immune system of neonates. We hypothesized that maternal short-chain fructooligosaccharide (scFOS) supplementation could accelerate the development of intestinal immunity in offspring. Thirty-four sows received a standard or a scFOS supplemented diet (10 g scFOS/d) for the last 4 weeks of gestation and the 4 weeks of lactation. Colostrum and milk immunoglobulins (Ig) and TGFß1 concentrations were evaluated on the day of delivery and at d 6 and d 21 postpartum. Piglet intestinal structure, the immunologic features of jejunal and ileal Peyer's patches, and mesenteric lymph node cells were analysed at postnatal d 21. Short-chain fatty acid concentrations were measured over time in the intestinal contents of suckling and weaned piglets. Colostral IgA (P<0.05) significantly increased because of scFOS and TGFß1 concentrations tended to improve (P<0.1). IFNγ secretion by stimulated Peyer's patch and mesenteric lymph node cells, and secretory IgA production by unstimulated Peyer's patch cells were increased (P<0.05) in postnatal d 21 scFOS piglets. These differences were associated with a higher proportion of activated CD25+CD4α+ T cells among the CD4+ helper T lymphocytes (P<0.05) as assessed by flow cytometry. IFNγ secretion was positively correlated with the population of activated T lymphocytes (P<0.05). Total short-chain fatty acids were unchanged between groups during lactation but were higher in caecal contents of d 90 scFOS piglets (P<0.05); specifically propionate, butyrate and valerate. In conclusion, we demonstrated that maternal scFOS supplementation modified the intestinal immune functions in piglets in association with increased colostral immunity. Such results underline the key role of maternal nutrition in supporting the postnatal development of mucosal immunity.


Assuntos
Colostro/imunologia , Suplementos Nutricionais , Intestinos/imunologia , Oligossacarídeos/farmacologia , Suínos/imunologia , Animais , Feminino , Intestinos/crescimento & desenvolvimento , Gravidez , Fenômenos Fisiológicos da Nutrição Pré-Natal , Suínos/metabolismo
11.
J Nutr Sci Vitaminol (Tokyo) ; 60(3): 167-75, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25078372

RESUMO

The aim of this study was to evaluate the effect of an infant formula supplemented with short-chain fructooligosaccharides (scFOS) on faecal concentration of bifidobacteria. Sixty-one healthy formula-fed infants participated in this double-blind controlled trial and were randomized to receive either the scFOS-supplemented formula (4 g/L scFOS) or the placebo-supplemented formula (4 g/L maltodextrins) until the age of 4 mo. Stool samples were analyzed for bifidobacteria at enrolment and at the age of 2 and 3 mo and for antipoliovirus IgA at the age of 4 mo. Parents completed a questionnaire to assess digestive tolerance. Change in faecal bifidobacteria after 2 mo were higher with scFOS compared to the placebo. At 4 mo, specific IgA tended to be higher with the scFOS group than with the placebo. Somatic growth and digestive tolerance were similar between groups. This study confirms that scFOS-supplemented formula can increase the concentration of faecal bifidobacteria while being well tolerated.


Assuntos
Bifidobacterium , Fezes/microbiologia , Alimentos Fortificados , Fórmulas Infantis/química , Oligossacarídeos/administração & dosagem , Anticorpos Antivirais/química , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Método Duplo-Cego , Ingestão de Energia , Fezes/química , Feminino , Seguimentos , Humanos , Imunoglobulina A/química , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido , Masculino , Vacinas contra Poliovirus/uso terapêutico
12.
Aquat Biosyst ; 9(1): 21, 2013 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-24237766

RESUMO

SUMMARY: In aquaculture, when alternative protein sources of Fish Meal (FM) in diets are investigated, Plant Proteins (PP) can be used. Among them, Vital Wheat Gluten (VWG) is a proteinaceous material obtained from wheat after starch extraction. "It is mainly composed of two types of proteins, gliadins and glutenins, which confer specific visco-elasticity that's to say ability to form a network providing suitable binding. This will lead to specific technological properties that are notably relevant to extruded feeds". Besides these properties, VWG is a high-protein ingredient with an interesting amino-acid profile. Whereas it is rather low in lysine, it contains more sulfur amino acids than other PP sources and it is high in glutamine, which is known to improve gut health and modulate immunity. VWG is a protein source with one of the highest nitrogen digestibility due to a lack of protease inhibitor activity and to the lenient process used to make the product. By this way, addition of VWG in diet does not adversely affect growth performance in many fish species, even at a high level, and may secure high PP level diets that can induce health damages.

13.
PLoS One ; 8(8): e71026, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23951074

RESUMO

Prebiotic fibres like short-chain fructo-oligosaccharides (scFOS) are known to selectively modulate the composition of the intestinal microbiota and especially to stimulate Bifidobacteria. In parallel, the involvement of intestinal microbiota in host metabolic regulation has been recently highlighted. The objective of the study was to evaluate the effect of scFOS on the composition of the faecal microbiota and on metabolic parameters in an animal model of diet-induced obesity harbouring a human-type microbiota. Forty eight axenic C57BL/6J mice were inoculated with a sample of faecal human microbiota and randomly assigned to one of 3 diets for 7 weeks: a control diet, a high fat diet (HF, 60% of energy derived from fat)) or an isocaloric HF diet containing 10% of scFOS (HF-scFOS). Mice fed with the two HF gained at least 21% more weight than mice from the control group. Addition of scFOS partially abolished the deposition of fat mass but significantly increased the weight of the caecum. The analysis of the taxonomic composition of the faecal microbiota by FISH technique revealed that the addition of scFOS induced a significant increase of faecal Bifidobacteria and the Clostridium coccoides group whereas it decreased the Clostridium leptum group. In addition to modifying the composition of the faecal microbiota, scFOS most prominently affected the faecal metabolome (e.g. bile acids derivatives, hydroxyl monoenoic fatty acids) as well as urine, plasma hydrophilic and plasma lipid metabolomes. The increase in C. coccoides and the decrease in C. leptum, were highly correlated to these metabolic changes, including insulinaemia, as well as to the weight of the caecum (empty and full) but not the increase in Bifidobacteria. In conclusion scFOS induce profound metabolic changes by modulating the composition and the activity of the intestinal microbiota, that may partly explain their effect on the reduction of insulinaemia.


Assuntos
Mucosa Intestinal/metabolismo , Intestinos/microbiologia , Metaboloma , Microbiota/efeitos dos fármacos , Oligossacarídeos/administração & dosagem , Animais , Bifidobacterium/classificação , Análise por Conglomerados , Dieta , Fezes/microbiologia , Vida Livre de Germes , Teste de Tolerância a Glucose , Humanos , Masculino , Metabolômica , Camundongos , Camundongos Obesos , Obesidade/etiologia , Oligossacarídeos/química
14.
Br J Nutr ; 104 Suppl 2: S1-63, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20920376

RESUMO

The different compartments of the gastrointestinal tract are inhabited by populations of micro-organisms. By far the most important predominant populations are in the colon where a true symbiosis with the host exists that is a key for well-being and health. For such a microbiota, 'normobiosis' characterises a composition of the gut 'ecosystem' in which micro-organisms with potential health benefits predominate in number over potentially harmful ones, in contrast to 'dysbiosis', in which one or a few potentially harmful micro-organisms are dominant, thus creating a disease-prone situation. The present document has been written by a group of both academic and industry experts (in the ILSI Europe Prebiotic Expert Group and Prebiotic Task Force, respectively). It does not aim to propose a new definition of a prebiotic nor to identify which food products are classified as prebiotic but rather to validate and expand the original idea of the prebiotic concept (that can be translated in 'prebiotic effects'), defined as: 'The selective stimulation of growth and/or activity(ies) of one or a limited number of microbial genus(era)/species in the gut microbiota that confer(s) health benefits to the host.' Thanks to the methodological and fundamental research of microbiologists, immense progress has very recently been made in our understanding of the gut microbiota. A large number of human intervention studies have been performed that have demonstrated that dietary consumption of certain food products can result in statistically significant changes in the composition of the gut microbiota in line with the prebiotic concept. Thus the prebiotic effect is now a well-established scientific fact. The more data are accumulating, the more it will be recognised that such changes in the microbiota's composition, especially increase in bifidobacteria, can be regarded as a marker of intestinal health. The review is divided in chapters that cover the major areas of nutrition research where a prebiotic effect has tentatively been investigated for potential health benefits. The prebiotic effect has been shown to associate with modulation of biomarkers and activity(ies) of the immune system. Confirming the studies in adults, it has been demonstrated that, in infant nutrition, the prebiotic effect includes a significant change of gut microbiota composition, especially an increase of faecal concentrations of bifidobacteria. This concomitantly improves stool quality (pH, SCFA, frequency and consistency), reduces the risk of gastroenteritis and infections, improves general well-being and reduces the incidence of allergic symptoms such as atopic eczema. Changes in the gut microbiota composition are classically considered as one of the many factors involved in the pathogenesis of either inflammatory bowel disease or irritable bowel syndrome. The use of particular food products with a prebiotic effect has thus been tested in clinical trials with the objective to improve the clinical activity and well-being of patients with such disorders. Promising beneficial effects have been demonstrated in some preliminary studies, including changes in gut microbiota composition (especially increase in bifidobacteria concentration). Often associated with toxic load and/or miscellaneous risk factors, colon cancer is another pathology for which a possible role of gut microbiota composition has been hypothesised. Numerous experimental studies have reported reduction in incidence of tumours and cancers after feeding specific food products with a prebiotic effect. Some of these studies (including one human trial) have also reported that, in such conditions, gut microbiota composition was modified (especially due to increased concentration of bifidobacteria). Dietary intake of particular food products with a prebiotic effect has been shown, especially in adolescents, but also tentatively in postmenopausal women, to increase Ca absorption as well as bone Ca accretion and bone mineral density. Recent data, both from experimental models and from human studies, support the beneficial effects of particular food products with prebiotic properties on energy homaeostasis, satiety regulation and body weight gain. Together, with data in obese animals and patients, these studies support the hypothesis that gut microbiota composition (especially the number of bifidobacteria) may contribute to modulate metabolic processes associated with syndrome X, especially obesity and diabetes type 2. It is plausible, even though not exclusive, that these effects are linked to the microbiota-induced changes and it is feasible to conclude that their mechanisms fit into the prebiotic effect. However, the role of such changes in these health benefits remains to be definitively proven. As a result of the research activity that followed the publication of the prebiotic concept 15 years ago, it has become clear that products that cause a selective modification in the gut microbiota's composition and/or activity(ies) and thus strengthens normobiosis could either induce beneficial physiological effects in the colon and also in extra-intestinal compartments or contribute towards reducing the risk of dysbiosis and associated intestinal and systemic pathologies.


Assuntos
Trato Gastrointestinal/microbiologia , Fenômenos Fisiológicos da Nutrição/efeitos dos fármacos , Valor Nutritivo , Prebióticos , Animais , Fermentação , Gastroenteropatias/prevenção & controle , Humanos , Sistema Imunitário/fisiologia , Absorção Intestinal , Minerais/metabolismo , Neoplasias/prevenção & controle , Obesidade/prevenção & controle
15.
J Nutr ; 138(9): 1712-8, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18716174

RESUMO

Dietary fibers may modulate insulin resistance and glucose homeostasis in dogs. Their efficacy is, however, dependent on their origin, physical properties, and fermentability in the large bowel. Eight healthy Beagle dogs were fed a commercial diet at twice their maintenance requirements until they became obese. They were then maintained in the obese state and used in a cross-over design study to evaluate the effects of short-chain fructooligosaccharide (scFOS) supplementation (1% wt:wt dry matter in the diet). The euglycemic hyperinsulinemic clamp technique was performed before and after fattening and at the end of each 6-wk cross-over period. Fat tissue biopsies were taken in food-deprived and postprandial phases to measure mRNA abundance of genes involved with fatty acid, glucose metabolism, or inflammation. Insulin resistance appeared progressively with fattening and the rate of glucose infusion during euglycemic clamp was lower (P < 0.05) at the end of the fattening period (7.39 mg.kg(-1).min(-1)) than at baseline (21.21 mg.kg(-1).min(-1)). In stable obese dogs, scFOS increased (P < 0.05) the rate of glucose infusion compared with control (7.77 vs. 4.72 mg.kg(-1).min(-1)). Plasma insulin and triglyceride concentrations were greater in obese than in lean dogs but were not altered by scFOS. Whereas mRNA was not affected in food-deprived dogs, scFOS increased uncoupling protein 2 (P = 0.05) and tended to increase carnitine palmitoyl transferase 1 adipose mRNA levels during the postprandial period (P = 0.09). Adding 1% scFOS to the diet of obese dogs decreases insulin resistance and appears to modulate the transcription of genes involved in fatty acid or glucose metabolism.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Resistência à Insulina/fisiologia , Obesidade/metabolismo , Oligossacarídeos/farmacologia , Tecido Adiposo/metabolismo , Animais , Glicemia/metabolismo , Peso Corporal , Colesterol/sangue , Estudos Cross-Over , Modelos Animais de Doenças , Cães , Feminino , Técnica Clamp de Glucose , Insulina/sangue , Metabolismo dos Lipídeos , Masculino , Obesidade/complicações , Oligossacarídeos/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Triglicerídeos/sangue
16.
Br J Nutr ; 99(2): 311-8, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17697398

RESUMO

A comparative, randomised, double-blind trial was performed in the medical departments of five hospitals to study the effects of regular consumption of short-chain fructo-oligosaccharides (sc-FOS) on the digestive comfort of subjects with minor functional bowel disorders (FBD). In step 1, 2235 subjects were questioned to assess the incidence and intensity of digestive disorders. In step 2, 105 of these patients diagnosed with minor FBD were randomised into two groups to receive either 5 g sc-FOS or 5 g placebo (sucrose and maltodextrins) per d over a 6-week period. The incidence and intensity of digestive disorders were assessed at the end of the treatment period (day 43) using the step 1 questionnaires. A quality-of-life questionnaire was also completed at the start and end of the treatment period to assess potential effects on well-being and social performance. In step 1, 44 % of the subjects questioned presented FBD, of whom 57.1 % suffered from minor FBD. In step 2, on day 43, the intensity of digestive disorders decreased by 43.6 % in the sc-FOS group v. a 13.8 % increase in the placebo group (P = 0.026). Symptoms were experienced less frequently by 75.0 % of subjects in the sc-FOS group, while 53.8 % of controls experienced no change (P = 0.064). Using the functional digestive disorders quality of life questionnaire, the discomfort item scores increased in the sc-FOS group (P = 0.031). However, expressed as change in quality of life (improvement, worsening or unchanged), daily activities were significantly improved in the sc-FOS group (P = 0.022). Regular consumption of sc-FOS may improve digestive comfort in a working population not undergoing medical treatment.


Assuntos
Doenças Funcionais do Colo/tratamento farmacológico , Suplementos Nutricionais , Digestão/efeitos dos fármacos , Frutose/uso terapêutico , Oligossacarídeos/uso terapêutico , Atividades Cotidianas , Adulto , Doenças Funcionais do Colo/fisiopatologia , Método Duplo-Cego , Feminino , Frutose/efeitos adversos , Humanos , Masculino , Oligossacarídeos/efeitos adversos , Cooperação do Paciente , Qualidade de Vida , Índice de Gravidade de Doença , Resultado do Tratamento
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