Determination of Butyrate Synthesis Capacity in Gut Microbiota: Quantification of but Gene Abundance by qPCR in Fecal Samples

Butyrate is formed in the gut during bacterial fermentation of dietary fiber and is attributed numerous beneficial effects on the host metabolism. We aimed to develop a method for the assessment of functional capacity of gut microbiota butyrate synthesis based on the qPCR quantification of bacterial gene coding butyryl-CoA:acetate CoA-transferase, the key enzyme of butyrate synthesis. In silico, we identified bacteria possessing but gene among human gut microbiota by searching but coding sequences in available databases. We designed and validated six sets of degenerate primers covering all selected bacteria, based on their phylogenetic nearness and sequence similarity, and developed a method for gene abundance normalization in human fecal DNA. We determined but gene abundance in fecal DNA of subjects with opposing dietary patterns and metabolic phenotypes-lean vegans (VG) and healthy obese omnivores (OB) with known fecal microbiota and metabolome composition. We found higher but gene copy number in VG compared with OB, in line with higher fecal butyrate content in VG group. We further found a positive correlation between the relative abundance of target bacterial genera identified by next-generation sequencing and groups of but gene-containing bacteria determined by specific primers. In conclusion, this approach represents a simple and feasible tool for estimation of microbial functional capacity

Increased vitamin B6 turnover is associated with greater mortality risk in the general US population: A prospective biomarker study

Background & aims: Vitamin B6 status and mortality risk are inversely associated in different patient groups, while prospective studies in the general population are lacking. Here, for the first time, we evaluated the association between biomarkers of vitamin B6 status and mortality risk in a large population-based study. Methods: The vitamin B6 vitamers pyridoxal-5'-phosphat (PLP) and 4-pyridoxic acid (4-PA) were measured by high-performance liquid chromatography in the National Health and Nutrition Examination Survey (NHANES) between 2005 and 2010. Participants' vital status and causes of death were recorded until December 2015. Multivariable Cox regression analyses were carried out to estimate Hazard Ratios (HRs) and 95% confidence intervals (CIs) of mortality across quintiles of PLP, 4-PA, and the ratio of 4-PA and PLP. Results: Out of 15,304 study participants aged between 20 and 85 years at baseline, 1666 (7.7%) died during a median follow-up time of 7.8 years. An inverse association between PLP and mortality was found in a multivariable model adjusted for socioeconomic and lifestyle factors but became statistically non-significant upon adjustment for routine biomarkers (C-reactive protein, creatinine, albumin, and alkaline phosphatase). There was a significant linear trend for a positive association between 4-PA levels and mortality risk in the fully adjusted regression model, although a comparison of extreme quintiles (quintile 5 vs. quintile 1) did not show a significant difference (HRQ5vs.Q1 (95% CI): 1.19 (0.93, 1.51), plinear trend = 0.02). A positive association between the 4-PA/PLP ratio and all-cause mortality was observed in the multivariable model, with an HRsQ5vs.Q1 of 1.45 (95% CI: 1.14, 1.85; plinear trend<0.0001). There were no significant associations between the biomarkers and cardiovascular or cancer mortality. The association between 4-PA/PLP and mortality risk was heterogeneous across age groups, and only statistically significant among participants older than 65 years at baseline (HRQ5vs.Q1 (95% CI): 1.72 (1.29, 2.29), plinear trend<0.0001). In this group, 4-PA/PLP was also associated with cancer mortality, with an HR Q5vs.Q1 of 2.16 (1.20, 3.90), plinear trend = 0.02). Conclusion: Increased vitamin B6 turnover, as indicated by a higher 4-PA/PLP ratio, was associated with all-cause and cancer mortality among the older U.S. general population. Intervention trials are needed to assess whether older individuals with a high 4-PA/PLP ratio would benefit from increased vitamin B6 intake. Keywords: 4-Pyridoxic acid; Mortality; Prospective study; Pyridoxal-5′-phosphat; Vitamin B6

Multi-omics signatures in new-onset diabetes predict metabolic response to dietary inulin: findings from an observational study followed by an interventional trial

AIM: The metabolic performance of the gut microbiota contributes to the onset of type 2 diabetes. However, targeted dietary interventions are limited by the highly variable inter-individual response. We hypothesized (1) that the composition of the complex gut microbiome and metabolome (MIME) differ across metabolic spectra (lean-obese-diabetes); (2) that specific MIME patterns could explain the differential responses to dietary inulin; and (3) that the response can be predicted based on baseline MIME signature and clinical characteristics. METHOD: Forty-nine patients with newly diagnosed pre/diabetes (DM), 66 metabolically healthy overweight/obese (OB), and 32 healthy lean (LH) volunteers were compared in a cross-sectional case-control study integrating clinical variables, dietary intake, gut microbiome, and fecal/serum metabolomes (16 S rRNA sequencing, metabolomics profiling). Subsequently, 27 DM were recruited for a predictive study: 3 months of dietary inulin (10 g/day) intervention. RESULTS: MIME composition was different between groups. While the DM and LH groups represented opposite poles of the abundance spectrum, OB was closer to DM. Inulin supplementation was associated with an overall improvement in glycemic indices, though the response was very variable, with a shift in microbiome composition toward a more favorable profile and increased serum butyric and propionic acid concentrations. The improved glycemic outcomes of inulin treatment were dependent on better baseline glycemic status and variables related to the gut microbiota, including the abundance of certain bacterial taxa (i.e., Blautia, Eubacterium halii group, Lachnoclostridium, Ruminiclostridium, Dialister, or Phascolarctobacterium), serum concentrations of branched-chain amino acid derivatives and asparagine, and fecal concentrations of indole and several other volatile organic compounds. CONCLUSION: We demonstrated that obesity is a stronger determinant of different MIME patterns than impaired glucose metabolism. The large inter-individual variability in the metabolic effects of dietary inulin was explained by differences in baseline glycemic status and MIME signatures. These could be further validated to personalize nutritional interventions in patients with newly diagnosed diabetes

Development of the VEGANScreener, : a Tool for a Quick Diet Quality Assessment among Vegans in Europe

Peer reviewe

Nutritional Factors in Skeletal Muscle Insulin Resistance Development

Nutritional Factors in Skeletal Muscle Insulin Resistance Development Jan Gojda Abstract Background. Diet composition ranks among etiological factors of insulin resistance (IR) and diabetes. Vegans, people consuming exclusively plant-based diet, have significantly lower prevalence of IR and thus represent a suitable model population for study of nutritional factors on IR development. Branched chain amino acids (BCAA) ranks among these factors. Aims and hypothesis. Aim of the observational study was to prove that vegans have better glucoregulatory functions and thus to validate "vegan vs. omnivore" model. Aim of the consecutive interventional study was to prove in this model that dietary intervention with BCAA leads to a group sepcific changes in the insulin function mesures. Methods. 11 vegans and 10 omnivorous controls were recruited in the observational study. Hyperinsulinemic euglycemic clamp (HEC) and muscle (SM) biopsies (amount of intramyocellular lipids (IMCL), mtDNA and the activity of citrate synthase (CS)) were performed. 8 vegans and 8 omnivores were consequently subjected to the intervention with 15 or 20 g of BCAA respectively. The examination was performed at the baseline, after the intervention and after 6 months wash-out period: anthropometry, HEC, arginine test, SM biopsy (CS, activity of..

Black Death in the Czech countries in the Middle-ages

When they saw the sea horizon Messinští mast Genoese galleys, which came from the business offices in the Crimea, certainly had no idea that they proclaim the most shattering pandemic in the history of the continent, black Pandemic of death. The disease, which affected all corners of Europe, which itself has disappeared After four centuries as mysteriously as she appeared, and todaymany question marks hanging. The more we know about the Black Death, the less traditional truthsremain in the light of new evidence unshaken. Never in the history of Europe has not been witnessed such a drastic event. never was not affected by the pandemic of this magnitude. Within a few years and died half of Europe's population. Significantly changing the structure ofthe population in the rural and in cities. But what struck even more than the mass of the populationand what pomření caused a profound change in collective behavior and mentality ofsociety, was the fact that the epidemic erupted with varying intensity at regularintervals various parts of Europe and the plague and death became part ofeveryday life. For many past efforts have been devoted to the issue of the Black Death. The aim of this research is a compilation of available sources with a focus on new knowledge of the etiology, course medieval pandemic in the Czech..

Nutritional Factors in Skeletal Muscle Insulin Resistance Development

Nutritional Factors in Skeletal Muscle Insulin Resistance Development Jan Gojda Abstract Background. Diet composition ranks among etiological factors of insulin resistance (IR) and diabetes. Vegans, people consuming exclusively plant-based diet, have significantly lower prevalence of IR and thus represent a suitable model population for study of nutritional factors on IR development. Branched chain amino acids (BCAA) ranks among these factors. Aims and hypothesis. Aim of the observational study was to prove that vegans have better glucoregulatory functions and thus to validate "vegan vs. omnivore" model. Aim of the consecutive interventional study was to prove in this model that dietary intervention with BCAA leads to a group sepcific changes in the insulin function mesures. Methods. 11 vegans and 10 omnivorous controls were recruited in the observational study. Hyperinsulinemic euglycemic clamp (HEC) and muscle (SM) biopsies (amount of intramyocellular lipids (IMCL), mtDNA and the activity of citrate synthase (CS)) were performed. 8 vegans and 8 omnivores were consequently subjected to the intervention with 15 or 20 g of BCAA respectively. The examination was performed at the baseline, after the intervention and after 6 months wash-out period: anthropometry, HEC, arginine test, SM biopsy (CS, activity of..

Black Death in the Czech countries in the Middle-ages

Když na mořském horizontu spatřili Messinští stěžně janovských galér, které se navracely z obchodního zastupitelství na Krymu, jistě netušili, že jim zvěstují nejdrtivější pandemii v dějinách evropského kontinentu, pandemii černé smrti. Nad nemocí, která zachvátila všechny kouty Evropy, a která sama zmizela po čtyřech stoletích stejně záhadně, jako se objevila, i dnes visí mnohé otazníky. Čím více o černé smrti víme, tím méně tradičních pravd zůstává ve světle nových důkazů neotřeseno. Nikdy v dějinách nebyla Evropa svědkem tak drastické události. Nikdy nebyla postižena pandemií takového rozsahu. Během několika let vymřela až polovina evropské populace. Výrazně se změnila struktura obyvatel na venkově i ve městech. To, co však zasáhlo ještě více než masové pomření obyvatelstva a co bylo příčinou hlubokých změn v kolektivním chování a mentalitě společnosti, byl fakt, že epidemie s různou intenzitou propukaly v pravidelných intervalech v různých koutech Evropy a mor a umírání se staly všední součástí života lidí. Již mnoho úsilí bylo v minulosti věnováno problematice černé smrti. Cílem této rešerše je kompilace dostupných pramenů se zaměřením na nové poznatky o etiologii onemocnění, průběhu středověké pandemie v českých zemích a jejím odrazu ve středověké společnosti.When they saw the sea horizon Messinští mast Genoese galleys, which came from the business offices in the Crimea, certainly had no idea that they proclaim the most shattering pandemic in the history of the continent, black Pandemic of death. The disease, which affected all corners of Europe, which itself has disappeared After four centuries as mysteriously as she appeared, and todaymany question marks hanging. The more we know about the Black Death, the less traditional truthsremain in the light of new evidence unshaken. Never in the history of Europe has not been witnessed such a drastic event. never was not affected by the pandemic of this magnitude. Within a few years and died half of Europe's population. Significantly changing the structure ofthe population in the rural and in cities. But what struck even more than the mass of the populationand what pomření caused a profound change in collective behavior and mentality ofsociety, was the fact that the epidemic erupted with varying intensity at regularintervals various parts of Europe and the plague and death became part ofeveryday life. For many past efforts have been devoted to the issue of the Black Death. The aim of this research is a compilation of available sources with a focus on new knowledge of the etiology, course medieval pandemic in the Czech...Kabinet dějin lékařstvíDivision of History of MedicineThird Faculty of Medicine3. lékařská fakult

Gut Microbiota as the Link between Elevated BCAA Serum Levels and Insulin Resistance

The microbiota-harboring human gut is an exquisitely active ecosystem that has evolved in a constant symbiosis with the human host. It produces numerous compounds depending on its metabolic capacity and substrates availability. Diet is the major source of the substrates that are metabolized to end-products, further serving as signal molecules in the microbiota-host cross-talk. Among these signal molecules, branched-chain amino acids (BCAAs) has gained significant scientific attention. BCAAs are abundant in animal-based dietary sources; they are both produced and degraded by gut microbiota and the host circulating levels are associated with the risk of type 2 diabetes. This review aims to summarize the current knowledge on the complex relationship between gut microbiota and its functional capacity to handle BCAAs as well as the host BCAA metabolism in insulin resistance development. Targeting gut microbiota BCAA metabolism with a dietary modulation could represent a promising approach in the prevention and treatment of insulin resistance related states, such as obesity and diabetes