12 research outputs found
Effects of the whole seed and a protein isolate of faba bean (Vicia faba) on the cholesterol metabolism of hypercholesterolaemic rats
The aim of the present work was to analyse the hypocholesterolaemic efficiency of a Vicia fabaprotein
isolate in relation to the intact legume. In addition, the mechanisms underlying the
effects of this isolate were investigated. Hypercholesterolaemic rats were divided into three
groups n10 3 and fed high-fat diets rich in cholesterol-containing casein, whole seeds of
Vicia faba or the protein isolate of faba beans as protein source, for 2 weeks ad libitum. The
protein isolate was prepared by isoelectric precipitation and spray dried. Analyses of serum,
liver and faeces, as well as of the activity of hepatic 3-hydroxy-3-methylglutaryl (HMG)-CoA
reductase, were assessed by enzymatic methods. The rats fed on Vicia faba diets showed
significantly lower body weights and energy intakes than rats fed on casein diets. The wholeseed
diet induced a significant reduction in plasma triacylglycerol. Feeding rats on diets
containing faba bean seeds, or the protein isolate, induced a significant decrease in plasma
(LDL+VLDL)-cholesterol but not in HDL-cholesterol. Hepatic cholesterol and triacylglycerol
were also reduced. The hypocholesterolaemic effects of Vicia faba were not the result of a
reduction in cholesterol synthesis as assessed from HMG-CoA reductase activity, but the result
of an increase in steroid faecal excretion. The faba bean-protein isolate obtained under our
experimental conditions was useful in improving the metabolic alterations induced by feeding
with a hypercholesterolaemic diet compared with casein. The effectiveness of the whole seeds
was higher than that of the protein isolate
Shifts in microbiota species and fermentation products in a dietary model enriched in fat and sucrose
The gastrointestinal tract harbours a âsuperorganismâ called the gut microbiota, which is known to play a crucial role in the onset and development of diverse diseases. This internal ecosystem, far from being a static environment, could be willingly manipulated by diet and dietary components. Feeding animals with high-fat sucrose diets entails diet-induced obesity, a model which is usually used in research to mimic the obese phenotype of Western societies.
The aim of the present study was to identify gut microbiota dysbiosis and associated metabolic changes produced in 5 male Wistar rats fed a high-fat sucrose (HFS) diet for six weeks and to compare it with the basal microbial composition. For this purpose, DNA extracted from faeces at baseline and after the treatment was analysed by amplification of the V4-V6 region of the 16S ribosomal DNA (rDNA) gene using 454 pyrosequencing. Short-chain fatty acids (SCFA), acetate, propionate and butyrate, were also evaluated by gas chromatography-mass spectrometry (GC-MS).
At the end of the treatment, gut microbiota composition significantly differed at phylum level (Firmicutes, Bacteroidetes and Proteobacteria) and class level (Erisypelotrichi, Deltaproteobacteria, Bacteroidia and Bacilli). Interestingly, Clostridia class showed a significant decrease after the HFS-diet treatment, which correlated with visceral adipose tissue, and is likely mediated by dietary carbohydrates. Of particular interest, Clostridium cluster XIVa species were significantly reduced and changes were identified in the relative abundance of other specific bacterial species (Mitsuokella jalaludinii, Eubacterium ventriosum, Clostridium sp. FCB90-3, Prevotella nanceiensis, Clostridium fusiformis, Clostridium sp. BNL1100 and Eubacterium cylindroides) that, in some cases, showed opposite trends to their relative families.
These results highlight the relevance of characterizing gut microbial population differences at species level and contribute to understand the plausible link between the
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diet and specific gut bacterial species that are able to influence the inflammatory status, intestinal barrier function and obesity development.
Keywords: gut microbiota, pyrosequencing, high-fat sucrose diet, short chain fatty acids, Erysipelotrich
Reshaping faecal gut microbiota composition by the intake of trans-resveratrol and quercetin in high-fat sucrose diet-fed rats
Dietâinduced obesity is associated to an imbalance in the normal gut microbiota composition. Resveratrol and quercetin, widely known for their health beneficial properties, have low bioavailability and, when reach the colon, they are targets of the gut microbial ecosystem. Hence, the use of these molecules in obesity might be considered as a potential strategy to modulate intestinal bacterial composition. The purpose of this study was to determine whether transâresveratrol and quercetin administration could counteract gut microbiota dysbiosis produced by highâfat sucrose diet (HFS) and in turn, improve gut health. Wistar rats were randomized into four groups fed a HFS diet supplemented or not with transâresveratrol (15 mg/kg BW/day), quercetin (30 mg/kg BW/day) or a combination of both polyphenols at those doses. Administration of both polyphenols together prevented bodyâweight gain and reduced serum insulin levels. Moreover, individual supplementation of transâresveratrol and quercetin effectively reduced serum insulin levels and insulin resistance. Quercetin supplementation generated a great impact on gut microbiota composition at different taxonomic levels, attenuating Firmicutes/Bacteroidetes ratio and inhibiting the growth of bacterial species previously associated to dietâinduced obesity (Erysipelotrichaceae, Bacillus, Eubacterium 1
cylindroides). Overall, the administration of quercetin was found to be effective in lessening HFS dietâinduced gut microbiota dysbiosis. In contrast, transâresveratrol supplementation alone or in combination with quercetin, scarcely modified the profile of gut bacteria, but acted at intestinal level altering the mRNA expression of tightâjunction proteins (TJPs) and inflammation associated genes
Metabolic faecal fingerprinting of trans-resveratrol and quercetin following a high-fat sucrose dietary model using liquid chromatography coupled to high-resolution mass spectrometry
Faecal nonâtargeted metabolomics deciphers metabolic endâproducts resulting from the interactions among food, host genetics, and gut microbiota. Faeces from Wistar rats fed a highâfat sucrose (HFS) diet supplemented with transâresveratrol and quercetin (separately or combined) were analysed by liquid chromatography coupled to highâresolution mass spectrometry (LCâHRMS). Metabolomics in faeces are categorised into four clusters based on the type of treatment. Tentative identification of significantly differing metabolites highlighted the presence of carbohydrate derivatives or conjugates (3âphenylpropyl glucosinolate and dTDPâDâmycaminose) in quercetin group. The transâresveratrol group was differentiated by compounds related to nucleotides (uridine monophosphate and 2,4âdioxotetrahydropyrimidine Dâribonucleotide). Marked associations between bacterial species (Clostridium genus) and the amount of some metabolites were identified. Moreover, transâresveratrol and resveratrolâderived microbial metabolites (dihydroresveratrol and lunularin) were also identified. Accordingly, this study confirms the usefulness of omicsâbased techniques to discriminate individuals depending on the physiological effect of food constituents and represents an interesting tool to assess the impact of future personalized therapies
Influence of Dietary Oil Content and Conjugated Linoleic Acid (CLA) on Lipid Metabolism Enzyme Activities and Gene Expression in Tissues of Atlantic Salmon (Salmo salar L.)
The overall objective is to test the hypothesis that conjugated linoleic acid (CLA) has beneficial effects in Atlantic salmon through affecting lipid and fatty acid metabolism. The specific aims of the present study were to determine the effects of CLA on some key pathways of fatty acid metabolism including fatty acid oxidation and highly unsaturated fatty acid (HUFA) synthesis. Salmon smolts were fed diets containing two levels of fish oil (low, ~18% and high, ~34%) containing three levels of CLA (a 1:1 mixture of 9-cis,trans-11 and trans-10,cis-12 at 0, 1 and 2% of diet) for 3 months. The effects of dietary CLA on HUFA synthesis and ÎČ-oxidation were measured and the expression of key genes in the fatty acid oxidation and HUFA synthesis pathways, and potentially important transcription factors, peroxisome proliferators activated receptors (PPARs), determined in selected tissues. Liver HUFA synthesis and desaturase gene expression was increased by dietary CLA and decreased by high dietary oil content. Carnitine palmitoyltransferase-I (CPT-I) activity and gene expression were generally increased by CLA in muscle tissues although dietary oil content had relatively little effect. In general CPT-I activity or gene expression was not correlated with ÎČ-oxidation. Dietary CLA tended to increase PPARα and ÎČ gene expression in both liver and muscle tissues, and PPARÎł in liver. In summary, gene expression and activity of the fatty acid pathways were altered in response to dietary CLA and/or oil content, with data suggesting that PPARs are also regulated in response to CLA. Correlations were observed between dietary CLA, liver HUFA synthesis and desaturase gene expression, and liver PPARα expression, and also between dietary CLA, CPT-I expression and activity, and PPARα expression in muscle tissues. In conclusion, this study suggests that dietary CLA has effects on fatty acid metabolism in Atlantic salmon and on PPAR transcription factors. However, further work is required to assess the potential of CLA as a dietary supplement, and the role of PPARs in the regulation of lipid metabolism in fish
Reshaping faecal gut microbiota composition by the intake of trans-resveratrol and quercetin in high-fat sucrose diet-fed rats
Effects of dietary lipid source and energy restriction on the liver fatty acid profile in zucker rats (fa/fa)
International audienc
Reshaping faecal gut microbiota composition by the intake of trans-resveratrol and quercetin in high-fat sucrose diet-fed rats
Dietâinduced obesity is associated to an imbalance in the normal gut microbiota composition. Resveratrol and quercetin, widely known for their health beneficial properties, have low bioavailability and, when reach the colon, they are targets of the gut microbial ecosystem. Hence, the use of these molecules in obesity might be considered as a potential strategy to modulate intestinal bacterial composition. The purpose of this study was to determine whether transâresveratrol and quercetin administration could counteract gut microbiota dysbiosis produced by highâfat sucrose diet (HFS) and in turn, improve gut health. Wistar rats were randomized into four groups fed a HFS diet supplemented or not with transâresveratrol (15 mg/kg BW/day), quercetin (30 mg/kg BW/day) or a combination of both polyphenols at those doses. Administration of both polyphenols together prevented bodyâweight gain and reduced serum insulin levels. Moreover, individual supplementation of transâresveratrol and quercetin effectively reduced serum insulin levels and insulin resistance. Quercetin supplementation generated a great impact on gut microbiota composition at different taxonomic levels, attenuating Firmicutes/Bacteroidetes ratio and inhibiting the growth of bacterial species previously associated to dietâinduced obesity (Erysipelotrichaceae, Bacillus, Eubacterium 1
cylindroides). Overall, the administration of quercetin was found to be effective in lessening HFS dietâinduced gut microbiota dysbiosis. In contrast, transâresveratrol supplementation alone or in combination with quercetin, scarcely modified the profile of gut bacteria, but acted at intestinal level altering the mRNA expression of tightâjunction proteins (TJPs) and inflammation associated genes
Effects of the whole seed and a protein isolate of faba bean (Vicia faba) on the cholesterol metabolism of hypercholesterolaemic rats
The aim of the present work was to analyse the hypocholesterolaemic efficiency of a Vicia fabaprotein
isolate in relation to the intact legume. In addition, the mechanisms underlying the
effects of this isolate were investigated. Hypercholesterolaemic rats were divided into three
groups n10 3 and fed high-fat diets rich in cholesterol-containing casein, whole seeds of
Vicia faba or the protein isolate of faba beans as protein source, for 2 weeks ad libitum. The
protein isolate was prepared by isoelectric precipitation and spray dried. Analyses of serum,
liver and faeces, as well as of the activity of hepatic 3-hydroxy-3-methylglutaryl (HMG)-CoA
reductase, were assessed by enzymatic methods. The rats fed on Vicia faba diets showed
significantly lower body weights and energy intakes than rats fed on casein diets. The wholeseed
diet induced a significant reduction in plasma triacylglycerol. Feeding rats on diets
containing faba bean seeds, or the protein isolate, induced a significant decrease in plasma
(LDL+VLDL)-cholesterol but not in HDL-cholesterol. Hepatic cholesterol and triacylglycerol
were also reduced. The hypocholesterolaemic effects of Vicia faba were not the result of a
reduction in cholesterol synthesis as assessed from HMG-CoA reductase activity, but the result
of an increase in steroid faecal excretion. The faba bean-protein isolate obtained under our
experimental conditions was useful in improving the metabolic alterations induced by feeding
with a hypercholesterolaemic diet compared with casein. The effectiveness of the whole seeds
was higher than that of the protein isolate