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

1964 ◽  
Vol 42 (11) ◽  
pp. 1605-1621 ◽  
Author(s):  
E. J. Davis ◽  
J. H. Quastel

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.

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
Justine Huart ◽  
Arianna Cirillo ◽  
Annie Saint-Remy ◽  
Jean-Marie Krzesinski ◽  
Pascal De Tullio ◽  
...  

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.


2002 ◽  
Vol 1565 (1) ◽  
pp. 55-63 ◽  
Author(s):  
Roger Busche ◽  
Joachim Dittmann ◽  
Hans-Dieter Meyer zu Düttingdorf ◽  
Uwe Glockenthör ◽  
Wolfgang von Engelhardt ◽  
...  

2015 ◽  
Vol 16 (4) ◽  
pp. 935-947 ◽  
Author(s):  
Fabíola Franklin de MEDEIROS ◽  
Leilson Rocha BEZERRA ◽  
Aderbal Marcos de Azevêdo SILVA ◽  
Heloisa CARNEIRO ◽  
Raissa Kiara Oliveira de MORAIS ◽  
...  

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.


2014 ◽  
Vol 26 (11) ◽  
pp. 1586-1596 ◽  
Author(s):  
Norm R. Hurst ◽  
Derek M. Kendig ◽  
Karnam S. Murthy ◽  
John R. Grider

2004 ◽  
Vol 27 (2) ◽  
pp. 105-113 ◽  
Author(s):  
Masahiro Tatara ◽  
Akira Yamazawa ◽  
Yoshiyuki Ueno ◽  
Hisatomo Fukui ◽  
Masafumi Goto ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document