30 research outputs found
Quantitative Profiling of Endogenous Fat-Soluble Vitamins and Carotenoids in Human Plasma Using an Improved UHPSFC-ESI-MS Interface
Analytical solutions
enabling the quantification of circulating
levels of liposoluble micronutrients such as vitamins and carotenoids
are currently limited to either single or a reduced panel of analytes.
The requirement to use multiple approaches hampers the investigation
of the biological variability on a large number of samples in a time
and cost efficient manner. With the goal to develop high-throughput
and robust quantitative methods for the profiling of micronutrients
in human plasma, we introduce a novel, validated workflow for the
determination of 14 fat-soluble vitamins and carotenoids in a single
run. Automated supported liquid extraction was optimized and implemented
to simultaneously parallelize 48 samples in 1 h, and the analytes
were measured using ultrahigh-performance supercritical fluid chromatography
coupled to tandem mass spectrometry in less than 8 min. An improved
mass spectrometry interface hardware was built up to minimize the
post-decompression volume and to allow better control of the chromatographic
effluent density on its route toward and into the ion source. In addition,
a specific make-up solvent condition was developed to ensure both
analytes and matrix constituents solubility after mobile phase decompression.
The optimized interface resulted in improved spray plume stability
and conserved matrix compounds solubility leading to enhanced hyphenation
robustness while ensuring both suitable analytical repeatability and
improved the detection sensitivity. The overall developed methodology
gives recoveries within 85ā115%, as well as within and between-day
coefficient of variation of 2 and 14%, respectively
Quantitative Profiling of Endogenous Fat-Soluble Vitamins and Carotenoids in Human Plasma Using an Improved UHPSFC-ESI-MS Interface
Analytical solutions
enabling the quantification of circulating
levels of liposoluble micronutrients such as vitamins and carotenoids
are currently limited to either single or a reduced panel of analytes.
The requirement to use multiple approaches hampers the investigation
of the biological variability on a large number of samples in a time
and cost efficient manner. With the goal to develop high-throughput
and robust quantitative methods for the profiling of micronutrients
in human plasma, we introduce a novel, validated workflow for the
determination of 14 fat-soluble vitamins and carotenoids in a single
run. Automated supported liquid extraction was optimized and implemented
to simultaneously parallelize 48 samples in 1 h, and the analytes
were measured using ultrahigh-performance supercritical fluid chromatography
coupled to tandem mass spectrometry in less than 8 min. An improved
mass spectrometry interface hardware was built up to minimize the
post-decompression volume and to allow better control of the chromatographic
effluent density on its route toward and into the ion source. In addition,
a specific make-up solvent condition was developed to ensure both
analytes and matrix constituents solubility after mobile phase decompression.
The optimized interface resulted in improved spray plume stability
and conserved matrix compounds solubility leading to enhanced hyphenation
robustness while ensuring both suitable analytical repeatability and
improved the detection sensitivity. The overall developed methodology
gives recoveries within 85ā115%, as well as within and between-day
coefficient of variation of 2 and 14%, respectively
Gut Microbiota Modulate the Metabolism of Brown Adipose Tissue in Mice
A two by two experimental study has been designed to determine the effect of gut microbiota on energy metabolism in mouse models. The metabolic phenotype of germ-free (GF, <i>n</i> = 20) and conventional (<i>n</i> = 20) mice was characterized using a NMR spectroscopy-based metabolic profiling approach, with a focus on sexual dimorphism (20 males, 20 females) and energy metabolism in urine, plasma, liver, and brown adipose tissue (BAT). Physiological data of age-matched GF and conventional mice showed that male animals had a higher weight than females in both groups. In addition, conventional males had a significantly higher total body fat content (TBFC) compared to conventional females, whereas this sexual dimorphism disappeared in GF animals (i.e., male GF mice had a TBFC similar to those of conventional and GF females). Profiling of BAT hydrophilic extracts revealed that sexual dimorphism in normal mice was absent in GF animals, which also displayed lower BAT lactate levels and higher levels of (<i>D</i>)-3-hydroxybutyrate in liver, plasma, and BAT, together with lower circulating levels of VLDL. These data indicate that the gut microbiota modulate the lipid metabolism in BAT, as the absence of gut microbiota stimulated both hepatic and BAT lipolysis while inhibiting lipogenesis. We also demonstrated that <sup>1</sup>H NMR metabolic profiles of BAT were excellent predictors of BW and TBFC, indicating the potential of BAT to fight against obesity
Gut Microbiota Modulate the Metabolism of Brown Adipose Tissue in Mice
A two by two experimental study has been designed to determine the effect of gut microbiota on energy metabolism in mouse models. The metabolic phenotype of germ-free (GF, <i>n</i> = 20) and conventional (<i>n</i> = 20) mice was characterized using a NMR spectroscopy-based metabolic profiling approach, with a focus on sexual dimorphism (20 males, 20 females) and energy metabolism in urine, plasma, liver, and brown adipose tissue (BAT). Physiological data of age-matched GF and conventional mice showed that male animals had a higher weight than females in both groups. In addition, conventional males had a significantly higher total body fat content (TBFC) compared to conventional females, whereas this sexual dimorphism disappeared in GF animals (i.e., male GF mice had a TBFC similar to those of conventional and GF females). Profiling of BAT hydrophilic extracts revealed that sexual dimorphism in normal mice was absent in GF animals, which also displayed lower BAT lactate levels and higher levels of (<i>D</i>)-3-hydroxybutyrate in liver, plasma, and BAT, together with lower circulating levels of VLDL. These data indicate that the gut microbiota modulate the lipid metabolism in BAT, as the absence of gut microbiota stimulated both hepatic and BAT lipolysis while inhibiting lipogenesis. We also demonstrated that <sup>1</sup>H NMR metabolic profiles of BAT were excellent predictors of BW and TBFC, indicating the potential of BAT to fight against obesity
Gut Microbiota Modulate the Metabolism of Brown Adipose Tissue in Mice
A two by two experimental study has been designed to determine the effect of gut microbiota on energy metabolism in mouse models. The metabolic phenotype of germ-free (GF, <i>n</i> = 20) and conventional (<i>n</i> = 20) mice was characterized using a NMR spectroscopy-based metabolic profiling approach, with a focus on sexual dimorphism (20 males, 20 females) and energy metabolism in urine, plasma, liver, and brown adipose tissue (BAT). Physiological data of age-matched GF and conventional mice showed that male animals had a higher weight than females in both groups. In addition, conventional males had a significantly higher total body fat content (TBFC) compared to conventional females, whereas this sexual dimorphism disappeared in GF animals (i.e., male GF mice had a TBFC similar to those of conventional and GF females). Profiling of BAT hydrophilic extracts revealed that sexual dimorphism in normal mice was absent in GF animals, which also displayed lower BAT lactate levels and higher levels of (<i>D</i>)-3-hydroxybutyrate in liver, plasma, and BAT, together with lower circulating levels of VLDL. These data indicate that the gut microbiota modulate the lipid metabolism in BAT, as the absence of gut microbiota stimulated both hepatic and BAT lipolysis while inhibiting lipogenesis. We also demonstrated that <sup>1</sup>H NMR metabolic profiles of BAT were excellent predictors of BW and TBFC, indicating the potential of BAT to fight against obesity
Gut Microbiota Modulate the Metabolism of Brown Adipose Tissue in Mice
A two by two experimental study has been designed to determine the effect of gut microbiota on energy metabolism in mouse models. The metabolic phenotype of germ-free (GF, <i>n</i> = 20) and conventional (<i>n</i> = 20) mice was characterized using a NMR spectroscopy-based metabolic profiling approach, with a focus on sexual dimorphism (20 males, 20 females) and energy metabolism in urine, plasma, liver, and brown adipose tissue (BAT). Physiological data of age-matched GF and conventional mice showed that male animals had a higher weight than females in both groups. In addition, conventional males had a significantly higher total body fat content (TBFC) compared to conventional females, whereas this sexual dimorphism disappeared in GF animals (i.e., male GF mice had a TBFC similar to those of conventional and GF females). Profiling of BAT hydrophilic extracts revealed that sexual dimorphism in normal mice was absent in GF animals, which also displayed lower BAT lactate levels and higher levels of (<i>D</i>)-3-hydroxybutyrate in liver, plasma, and BAT, together with lower circulating levels of VLDL. These data indicate that the gut microbiota modulate the lipid metabolism in BAT, as the absence of gut microbiota stimulated both hepatic and BAT lipolysis while inhibiting lipogenesis. We also demonstrated that <sup>1</sup>H NMR metabolic profiles of BAT were excellent predictors of BW and TBFC, indicating the potential of BAT to fight against obesity
Gut Microbiota Modulate the Metabolism of Brown Adipose Tissue in Mice
A two by two experimental study has been designed to determine the effect of gut microbiota on energy metabolism in mouse models. The metabolic phenotype of germ-free (GF, <i>n</i> = 20) and conventional (<i>n</i> = 20) mice was characterized using a NMR spectroscopy-based metabolic profiling approach, with a focus on sexual dimorphism (20 males, 20 females) and energy metabolism in urine, plasma, liver, and brown adipose tissue (BAT). Physiological data of age-matched GF and conventional mice showed that male animals had a higher weight than females in both groups. In addition, conventional males had a significantly higher total body fat content (TBFC) compared to conventional females, whereas this sexual dimorphism disappeared in GF animals (i.e., male GF mice had a TBFC similar to those of conventional and GF females). Profiling of BAT hydrophilic extracts revealed that sexual dimorphism in normal mice was absent in GF animals, which also displayed lower BAT lactate levels and higher levels of (<i>D</i>)-3-hydroxybutyrate in liver, plasma, and BAT, together with lower circulating levels of VLDL. These data indicate that the gut microbiota modulate the lipid metabolism in BAT, as the absence of gut microbiota stimulated both hepatic and BAT lipolysis while inhibiting lipogenesis. We also demonstrated that <sup>1</sup>H NMR metabolic profiles of BAT were excellent predictors of BW and TBFC, indicating the potential of BAT to fight against obesity
Gut Microbiota Modulate the Metabolism of Brown Adipose Tissue in Mice
A two by two experimental study has been designed to determine the effect of gut microbiota on energy metabolism in mouse models. The metabolic phenotype of germ-free (GF, <i>n</i> = 20) and conventional (<i>n</i> = 20) mice was characterized using a NMR spectroscopy-based metabolic profiling approach, with a focus on sexual dimorphism (20 males, 20 females) and energy metabolism in urine, plasma, liver, and brown adipose tissue (BAT). Physiological data of age-matched GF and conventional mice showed that male animals had a higher weight than females in both groups. In addition, conventional males had a significantly higher total body fat content (TBFC) compared to conventional females, whereas this sexual dimorphism disappeared in GF animals (i.e., male GF mice had a TBFC similar to those of conventional and GF females). Profiling of BAT hydrophilic extracts revealed that sexual dimorphism in normal mice was absent in GF animals, which also displayed lower BAT lactate levels and higher levels of (<i>D</i>)-3-hydroxybutyrate in liver, plasma, and BAT, together with lower circulating levels of VLDL. These data indicate that the gut microbiota modulate the lipid metabolism in BAT, as the absence of gut microbiota stimulated both hepatic and BAT lipolysis while inhibiting lipogenesis. We also demonstrated that <sup>1</sup>H NMR metabolic profiles of BAT were excellent predictors of BW and TBFC, indicating the potential of BAT to fight against obesity
Stability and Robustness of Human Metabolic Phenotypes in Response to Sequential Food Challenges
High-resolution spectroscopic profiles of biofluids can define metabolic phenotypes, providing a window onto the impact of diet on health to reflect geneāenvironment interactions. <sup>1</sup>H NMR spectroscopic profiling was used to characterize the effect of nutritional intervention on the stability of the metabolic phenotype of 7 individuals following a controlled 7 day dietary protocol. Inter-individual metabolic differences influenced proportionally more of the spectrum than dietary modulation, with certain individuals displaying a greater stability of metabolic phenotypes than others. Correlation structures between urinary metabolites were identified and used to map inter-individual pathway differences. Choline degradation was the pathway most affected by the individual, suggesting that the gut microbiota influence host metabolic phenotypes. This influence was further emphasized by the highly correlated excretion of the microbialāmammalian co-metabolites phenylacetylglutamine, 4-cresylsulfate (<i>r</i> = 0.87), and indoxylsulfate (<i>r</i> = 0.67) across all individuals. Above the background of inter-individual differences, clear biochemical effects of single type dietary interventions, animal protein, fruit and wine intake, were observed; for example, the spectral variance introduced by fruit ingestion was attributed to the metabolites tartrate, proline betaine, hippurate, and 4-hydroxyhippurate. This differential metabolic baseline and response to selected dietary challenges highlights the importance of understanding individual differences in metabolism and provides a rationale for evaluating dietary interventions and stratification of individuals with respect to guiding nutrition and health programmes
Specific Dietary Preferences Are Linked to Differing Gut Microbial Metabolic Activity in Response to Dark Chocolate Intake
Systems biology approaches are providing novel insights
into the
role of nutrition for the management of health and disease. In the
present study, we investigated if dietary preference for dark chocolate
in healthy subjects may lead to different metabolic response to daily
chocolate consumption. Using NMR- and MS-based metabolic profiling
of blood plasma and urine, we monitored the metabolic response of
10 participants stratified as chocolate desiring and eating regularly
dark chocolate (CD) and 10 participants stratified as chocolate indifferent
and eating rarely dark chocolate (CI) to a daily consumption of 50
g of dark chocolate as part of a standardized diet over a one week
period. We demonstrated that preference for chocolate leads to different
metabolic response to chocolate consumption. Daily intake of dark
chocolate significantly increased HDL cholesterol by 6% and decreased
polyunsaturated acyl ether phospholipids. Dark chocolate intake could
also induce an improvement in the metabolism of long chain fatty acid,
as noted by a compositional change in plasma fatty acyl carnitines.
Moreover, a relationship between regular long-term dietary exposure
to a small amount of dark chocolate, gut microbiota, and phenolics
was highlighted, providing novel insights into biological processes
associated with cocoa bioactives