MO095THE FECAL ABUNDANCE OF SHORT CHAIN FATTY ACIDS IS INCREASED IN MEN WITH A NON-DIPPING BLOOD PRESSURE PROFILE

Abstract Background and Aims Gut microbiota (GM) has been involved in the pathophysiology of hypertension (HT), possibly via its role in the production of short chain fatty acids (SCFAs) from diet carbohydrate fermentation. The absence of a significant drop in night-time BP (also known as the non-dipping BP profile) measured by 24-hour ambulatory BP monitoring (24h-ABPM) has been associated with poor renal and cardiovascular outcomes, independently of HT. The putative link between GM-derived metabolites and BP dipping status is still unknown. Method We investigated a cohort of male volunteers who were prospectively recruited and subjected to 24h-ABPM, stool sample collection and a medical questionnaire. A patient was categorized as non-dipper if the ratio between night and day systolic BP was >0.9. The patients were categorized in two groups, i.e. NT or HT, on the basis of the European Society of Hypertension criteria. Metabolomics analyses were conducted using Nuclear Magnetic Resonance. Fecal concentrations of acetate, butyrate and propionate were obtained by integrating the signals at 1.93 ppm, 1.56 ppm and 1.05 ppm, respectively. Mann-Whitney test and Chi-square test were used to compare continuous and categorical variables, respectively. Results Our 44-case cohort included 13 non-dippers (29.6%) and 31 dippers, with 35 HT (79.4%) and 9 NT patients. Ten non-dippers (28.6%) and 25 dippers were HT. Nineteen HT patients were under anti-hypertensive medications (43.1%), including 7 non-dippers and 12 dippers. The mean age and body mass index (BMI) of the cohort were 50.8±9.5 years and 26.3±3.5 kg/m², respectively. No significant difference in age, BMI, smoking habits, alcohol consumption, familial HT, personal history of diabetes, cardiovascular or gastro-intestinal disorders was observed between dippers and non-dippers. The relative quantification of fecal SCFAs showed higher amounts of acetate, butyrate and propionate in the stools of non-dippers versus dippers (p=0.0252, p=0.0468, and p=0.0496, respectively; n=44 in toto) (Figure 1A). Similarly, the fecal amounts of acetate, butyrate and propionate were higher in non-dippers versus dippers in patients without anti-hypertensive medications (p=0.0414, p=0.0108, and p=0.0602, respectively; n=25 in toto) (Figure 1B). When focusing only on HT patients without any anti-hypertensive medications, a not significant trend for higher amounts of the 3 main SCFAs was still found in the stools of non-dippers versus dippers (p=0.0556; n=16 in toto). Conclusion Our pilot study highlights a putative link between GM-derived SCFAs and the BP dipping status, despite the BP status itself or the anti-hypertensive medications. No significant confounding factors were found between dippers and non-dippers in our cohort. The non-dipping BP profile is thought to reflect the disruption of the circadian BP rhythm. A circadian misalignment between peripheral and central clocks has also been described in the GM of jetlagged animals and patients, which may in turn perturb the rhythmic secretion of metabolites. One may thus speculate that the non-dipping BP profile may be linked to an altered homeostasis of GM-derived SCFAs. Although confirmatory data in larger cohorts are required, our original observations unravel innovative pathophysiological pathways in the field of the circadian regulation of BP levels.

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Greenhouse gases, short-chain fatty acids and ruminal pH in vitro of biodiesel byproducts to replace corn silage

Revista Brasileira de Saúde e Produção Animal ◽

10.1590/s1519-99402015000400017 ◽

2015 ◽

Vol 16 (4) ◽

pp. 935-947 ◽

Cited By ~ 5

Author(s):

Fabíola Franklin de MEDEIROS ◽

Leilson Rocha BEZERRA ◽

Aderbal Marcos de Azevêdo SILVA ◽

Heloisa CARNEIRO ◽

Raissa Kiara Oliveira de MORAIS ◽

...

Keyword(s):

Fatty Acids ◽

Ricinus Communis ◽

Short Chain Fatty Acids ◽

Rumen Fermentation ◽

Gas Production ◽

Corn Silage ◽

Short Chain ◽

Acetate Butyrate ◽

Chain Fatty Acids

SUMMARY The aim of the study was evaluate the production potential for methane (CH4) and carbon dioxide (CO2), short-chain fatty acids, ammonia nitrogen (N-NH3) and pH by semi-automated techniquein vitro from biodiesel byproducts cottonseed cake (Gossypium hirsutum), castor bean (Ricinus communis), moringa cake (Moringa oleifera), jatropha cake (Jatropha curcas) and sunflower cake (Helianthus annuus) substituting corn silage in increasing levels, 0, 30, 50 and 70%. The experimental design used was completely randomized in a 5 x 4 factorial arrangement (byproducts and substitution levels). The inoculum for the in vitro incubations was obtained from three Holstein cows with rumen fistulas. In the experiment, the conditions were verified for the differences in potential gas production among the ingredients. The byproduct of cotton was the ingredient with the greatest potential to produce acetate, butyrate, CO2 and CH4. The byproduct of moringa had the lowest potential for the production of acetate, butyrate, CO2 and CH4 from in vitro degraded dry matter and a greater potential for the production of propionate. Among the byproducts studied, moringa was distinguished for promoting mitigation of CH4 and obtaining levels of pH and N-NH3 satisfactory for maximum rumen fermentation; thus, it is recommended the byproduct of moringa to replace corn silage because reduces environmental impact without impairingin vitro rumen fermentation.

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THE EFFECTS OF SHORT-CHAIN FATTY ACIDS AND STARVATION ON THE METABOLISM OF GLUCOSE AND LACTATE BY THE PERFUSED GUINEA PIG HEART

Canadian Journal of Biochemistry ◽

10.1139/o64-172 ◽

1964 ◽

Vol 42 (11) ◽

pp. 1605-1621 ◽

Cited By ~ 24

Author(s):

E. J. Davis ◽

J. H. Quastel

Keyword(s):

Fatty Acids ◽

Guinea Pig ◽

Lactate Production ◽

Short Chain Fatty Acids ◽

High Rate ◽

Short Chain ◽

Lactate Oxidation ◽

Exogenous Glucose ◽

Acetate Butyrate ◽

Chain Fatty Acids

Uniformly labelled14C-glucose, when present at a concentration of 5 mM, is oxidized to14CO2by perfused guinea pig hearts at a rate of 10 μmoles per g wet weight per hour. Radioactivity is incorporated into glutamate, glutamine, alanine, aspartate, and heart proteins. During perfusion for 1 hour there is a high rate of incorporation of14C-glucose into glycogen and very little radioactive lactate accumulates. The cardiac glycogen is not increased.The oxidation of14C-glucose to14CO2by perfused hearts is suppressed more than 90% by prolonged starvation or by addition of acetate, butyrate, or pentanoate. The incorporation of radioactivity into glutamate and glutamine is almost completely blocked, while the radioactive labelling in alanine is undiminished. Cardiac glycogen of guinea pigs is increased approximately threefold by a 72-hour fast. Lactate production is increased in hearts of starved animals and by exogenous fatty acids. The short-chain fatty acids mentioned increase the net incorporation of exogenous glucose into cardiac glycogen, and there is apparently less net glycogenolysis in their presence than in their absence. Propionate reduces glucose oxidation to CO2by about 40% and has a much less pronounced effect on incorporation of glucose carbon into glutamate than that of acetate or butyrate. It has little effect on incorporation of exogenous glucose into cardiac glycogen, or on the amount of lactate which accumulates in the perfusing medium.1-14C-Lactate and 2-14C-lactate are rapidly oxidized to14CO2, and radioactivity from 2-14C-lactate is incorporated into glutamate, glutamine, alanine, and aspartate. Starvation, or the presence of acetate, butyrate, or pentanoate, suppresses lactate oxidation and incorporation of its carbon into glutamate and glutamine. The utilization of14C-lactate is diminished by these fatty acids to about the same extent as that of14C-glucose.These results may be explained by an inhibitory effect of acetyl-CoA on pyruvate oxidation by guinea pig hearts.1-14C-Acetate, 1-,4C-propionate, and 1-14C-butyrate are rapidly oxidized to14CO2and the labelled C is incorporated into glutamate, glutamine, and aspartate. Oxidation of acetate is not affected by starvation or by the presence of glucose or of propionate.

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Effects of Short Chain Fatty Acids (SCFAs) Modulation on Potentially Diarrhea Causing Pathogens in Yaks Through Metagenomics Sequencing

10.21203/rs.3.rs-91179/v1 ◽

2020 ◽

Author(s):

Kun Li ◽

Zhibo Zeng ◽

Juanjuan Liu ◽

Lulu Pei ◽

Yaping Wang ◽

...

Keyword(s):

Fatty Acids ◽

Diarrheal Disease ◽

Short Chain Fatty Acids ◽

Caproic Acid ◽

Isobutyric Acid ◽

Short Chain ◽

Klebsiella Pneumonia ◽

Intestinal Epithelial ◽

Significant Difference ◽

Chain Fatty Acids

Abstract Yaks are of great importance on the plateau; however, an emerging endemic diarrheal disease during the last few years is posing a great threat to the health of these animals. Yaks have special gut microbiotal community and short-chain fatty acids (SCFAs) which are not only the principle nutrient substrates of intestinal epithelial cells but can also regulate the epithelial barrier. Until now, metagenomics sequencing has not been reported in diarrheal yaks. A scarce information is available regarding the levels of fecal SCFAs and diarrhea in yaks. The purpose of our study was to identify the potential pathogens that cause the emerging diarrhea and also to explore the potential relationship of short-chain fatty acids in this issue. We estimated diarrhea rate in yaks after collecting the equal number of fecal samples from affected animals. Metagenomics sequencing and quantitative analysis of SCFAs were performed which revealed 15-25% and 5-10% prevalence in diarrheal yak’s calves and adults yaks respectively. Significant difference was observed in GC contents (44.69%~46.08% vs 46.12%~46.38%) under two reference groups (p<0.05). Violin box plot also showed the higher degree of dispersion in gene abundance distribution of diarrhea yaks, while genes of normal yaks were relatively gathered. We found 366163 significant differential abundance genes in diarrheal yaks, with 141305 up-regulated and 224858 down-regulated genes as compared with normal yaks via DESeq analysis. Metagenomic binning analysis indicated the higher significant of bin 33 (Bacteroidales) (p<0.05) in diarrheal animals, while bin 10 (p<0.0001), bin 30 (Clostridiales) (p<0.05), bin 51 (Lactobacillales) (p<0.05), bin 8 (Lachnospiraceae) (p<0.05) and bin 47 (Bacteria) (p<0.05) were obviously higher in normal animals. At different levels, an obviously difference in Phylum, Class, Oder, Family, Genus and Species was noticed as 4, 8, 8, 16, 17 and 30 respectively. Compared with healthy yaks, Acetic acid (p<0.01), Propionic acid (p<0.01), Butyric acid (p<0.01), Isobutyric acid, Isovaleric acid (p<0.05) and Caproic acid (p<0.01) were all observed obviously at lower rate in diarrheal yaks. In conclusion, besides the increased pathogens level of Staphylococcus aureus, Babesia ovata, Anaplasma phagocytophilum, Bacteroides fluxus, viruses, Klebsiella pneumonia, and inflammation-related bacteria; the decreased of SCFAs caused by the imbalance of intestinal microbiota may potentially leads to emergence of diarrhea in yaks.

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RESPIRATION OF MYCOBACTERIUM TUBERCULOSIS, STRAIN BCG, IN THE PRESENCE OF SHORT CHAIN FATTY ACIDS

Canadian Journal of Microbiology ◽

10.1139/m56-044 ◽

1956 ◽

Vol 2 (3) ◽

pp. 372-379 ◽

Cited By ~ 2

Author(s):

E. Pascoe ◽

J. H. Quastel

Keyword(s):

Fatty Acids ◽

Mycobacterium Tuberculosis ◽

Oxygen Consumption ◽

Short Chain Fatty Acids ◽

Short Chain ◽

Oxygen Utilization ◽

Tuberculosis Strain ◽

Mycobacterium Tuberculosis Strain ◽

Acetate Butyrate ◽

Chain Fatty Acids

Rates of oxygen consumption by washed suspensions of Mycobacterium tuberculosis, var. bovis, strain BCG, in the presence of short chain fatty acids and other substrates have been studied. Whereas the presence of acetate, butyrate, and hexanoate leads to increased but constant rates of respiration, that of propionate, pentanoate, and heptanoate leads to increased rates of respiration that diminish markedly with time. Admixture of glucose or glycerol with short chain even-numbered fatty acids gives additive rates of oxygen consumption. Admixture, however, of glucose or glycerol with odd-numbered short chain fatty acids prevents the fall off in respiration and leads to increased and constant rates of oxygen utilization. These effects of glucose or glycerol arc not due to the formation of fumarate or malate or of pyruvate or acetate. Mixtures of odd-numbered and even-numbered short chain fatty acids give rates of respiration which are (with the exception of acetate) those of the odd-numbered fatty acids alone. Acetoacetate and β-hydroxybutyrate resemble the short chain even-numbered fatty acids in this respect.

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Acetate, butyrate and proline uptake in the caecum and colon of prairie voles (Microtus ochrogaster)

Journal of Experimental Biology ◽

10.1242/jeb.176.1.285 ◽

1993 ◽

Vol 176 (1) ◽

pp. 285-297

Author(s):

I. D. Hume ◽

W. H. Karasov ◽

B. W. Darken

Keyword(s):

Fatty Acids ◽

Metabolic Rate ◽

Distal Colon ◽

Short Chain Fatty Acids ◽

Proximal Colon ◽

Microtus Ochrogaster ◽

Short Chain ◽

Prairie Voles ◽

Acetate Butyrate ◽

Chain Fatty Acids

We have measured unidirectional uptake (not transmural flux) of acetate, butyrate and proline by everted sleeves of intact tissue from the jejunum, caecum, proximal colon and distal colon of prairie voles (Microtus ochrogaster). There was active (i.e. Na(+)-dependent) transport of L-proline in the jejunum, but we found no evidence for it in any region of the hindgut (i.e. the caecum, proximal colon and distal colon). Uptake of acetate was carrier-mediated in all three regions of the hindgut, but the Jmax and apparent Km (< or = 1.5 mmol l-1) were low, and uptake was primarily passive over the concentration range 10–50 mmol l-1, which spanned measured acetate levels in the caecum and proximal colon. At 100 mmol l-1, acetate uptake (nmol min-1 cm-2) was higher (P < 0.001) in distal colon (359 +/− 33) than in the proximal colon (225 +/− 17) and caecum (150 +/− 5) (mean +/− S.E., N = 8). Uptakes summed over the length of each region were also higher (P < 0.001) in the distal colon at 100 mmol l-1, but not at low concentrations (0.1 mmol l-1). Uptakes normalized to diffusion coefficients were higher for butyrate than acetate and were lowest for L-glucose (which is absorbed passively via an aqueous pathway) in all regions, indicating that uptake of the short-chain fatty acids involves solubilization in the lipid bilayer of the apical membrane. The short-chain fatty acids absorbed from the hindgut of the vole were equivalent to 22% of standard metabolic rate or 15% of resting (but fed) metabolic rate.

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