Biogenesis of dicarboxylic acids in rat liver homogenate studied by 13C labeling

1991 ◽  
Vol 261 (6) ◽  
pp. E719-E724
Author(s):  
S. J. Jin ◽  
K. Y. Tserng
Keyword(s):  
Fatty Acids ◽  
Rat Liver ◽  
Liver Homogenate ◽  
Dicarboxylic Acids ◽  
Long Chain Fatty Acids ◽  
Beta Oxidation ◽  
Selected Ion Monitoring ◽  
Medium Chain ◽  
Long Chain ◽  
Chain Fatty Acids

The aim of this investigation is to assess whether long-chain fatty acids can be a substrate for omega-oxidation and the subsequent beta-oxidation to produce medium-chain dicarboxylic acids normally found in urine. Isolated rat liver 10,000 g supernatant and pellet fractions were used as the source of enzymes. The metabolism of palmitate was studied using [1,2,3,4-13C4]hexadecanoic acid as tracer. Selected ion monitoring mass spectrometry was utilized for the determination of isotope enrichments in precursor and products. Palmitate was found to be a good substrate for omega-oxidation; the rate was only slightly slower than decanoate. The beta-oxidation of [1,2,3,4-13C4]hexadecanedioic acid yielded labeled adipic, suberic, and sebacic acids. Isotope distribution in these dicarboxylic acids consisted mostly of unlabeled molecules (M + 0) and molecules labeled with four 13C (M + 4), in agreement with a beta-oxidation initiated equally from both carboxyl ends of the precursor. Significant enrichments (1-8%) with only two 13C labels (M + 2) indicate a partial bidirectional beta-oxidation. The direct metabolic conversion of hexadecanedioate to succinate was documented by the significant enrichment (1.40-1.90%) in M + 4 of succinate. These data indicate that long-chain fatty acids can be a substrate for the production of medium-chain dicarboxylates and the eventual direct conversion to succinate.

scholarly journals Differential Effects of Fatty Acid Saturation and Chain Length on NASH in Juvenile Iberian Pigs

2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 682-682 ◽  
Author(s):  
Kayla Dillard ◽  
Morgan Coffin ◽  
Gabriella Hernandez ◽  
Victoria Smith ◽  
Catherine Johnson ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Body Weight ◽  
Fatty Acid ◽  
Liver Injury ◽  
Olive Oil ◽  
Coconut Oil ◽  
Long Chain Fatty Acids ◽  
Medium Chain ◽  
Long Chain ◽  
Chain Fatty Acids

Abstract Objectives Non-alcoholic fatty liver disease (NAFLD) represents the major cause of pediatric chronic liver pathology in the United States. The objective of this study was to compare the relative effect of inclusion of isocaloric amounts of saturated medium-chain fatty acids (hydrogenated coconut oil), saturated long-chain fatty acids (lard) and unsaturated long-chain fatty acids (olive oil) on endpoints of NAFLD and insulin resistance. Methods Thirty-eight 15-d-old Iberian pigs were fed 1 of 4 diets containing (g/kg body weight × d) 1) control (CON; n = 8): 0 g fructose, 10.5 g fat, and 187 kcal metabolizable energy (ME), 2) lard (LAR; n = 10): 21.6 g fructose, 17.1 g fat (100% lard) and 299 kcal ME, 3) hydrogenated coconut oil (COCO; n = 10): 21.6 g fructose, 16.9 g fat (42.5% lard and 57.5% coconut oil) and 299 kcal ME, and 4) olive oil (OLV, n = 10): 21.6 g fructose, 17.1 g fat (43.5% lard and 56.5% olive oil) and 299 kcal ME, for 9 consecutive weeks. Body weight was recorded every 3 d. Serum markers of liver injury and dyslipidemia were measured on d 60 at 2 h post feeding, with all other serum measures assessed on d 70. Liver tissue was collected on d 70 for histology, triacylglyceride (TG) quantification, and metabolomics analysis. Results Tissue histology indicated the presence of steatosis in LAR, COCO and OLV compared with CON (P ≤ 0.001), with a further increase in in non-alcoholic steatohepatitis (NASH) in OLV and COCO compared with LAR (P ≤ 0.01). Alanine and aspartate aminotransferases were higher in COCO and OLV (P ≤ 0.01) than CON. All treatment groups had lower liver concentrations of methyl donor's choline and betaine versus CON, while bile acids were differentially changed (P ≤ 0.05). COCO had higher levels of TGs with less carbons (Total carbons < 52) than all other groups (P ≤ 0.05). Several long-chain acylcarnitines involved in fat oxidation were higher in OLV versus all other groups (P ≤ 0.05). Conclusions Inclusion of fats enriched in medium-chain saturated and long-chain unsaturated fatty acids in a high-fructose high-fat diet increased liver injury, compared with fats with a long-chain saturated fatty acid profile. Further research is required to investigate the mechanisms causing this difference in physiological response to these dietary fat sources. Funding Sources ARI, AcornSeekers.

Caprenin 1. Digestion, Absorption, and Rearrangement in Thoracic Duct-Cannulated Rats

1991 ◽  
Vol 10 (3) ◽  
pp. 325-340 ◽  
Author(s):  
D. R. Webb ◽  
R. A. Sanders
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Female Rats ◽  
Acid Uptake ◽  
Long Chain Fatty Acids ◽  
Male And Female ◽  
Medium Chain ◽  
Male And Female Rats ◽  
Long Chain ◽  
Chain Fatty Acids

Caprenin (CAP) is a triglyceride that primarily contains caprylic (C8:0), capric (C10:0), and behenic (C22:0) acids. This study was undertaken to determine whether or not CAP is qualitatively digested, absorbed, and rearranged like other dietary fats and oils that contain these medium-chain and very long-chain fatty acids. In vitro results showed that neat CAP, coconut oil (CO) and peanut oil (PO) were hydrolyzed by porcine pancreatic lipase. All of the neat triglycerides also were digested in vivo by both male and female rats. This was shown by the recovery of significantly more extractable lymphatic fat than with fat-free control animals and by the recovery of orally administered triglyceride-derived fatty acids in lymph triglycerides. However, substantially more PO (74%) and CO (51%) were recovered in lymph relative to CAP (10%). These quantitative differences are consistent with the fatty acid composition of each triglyceride and primary routes of fatty acid uptake. The 24-h lymphatic recovery of CAP-derived C8:0, C10:0, and C22:0 averaged 3.9%, 17.8%, and 11.2%, respectively, for male and female rats. The C8:0 and C10:0 results approximated those obtained with CO (2.0% and 16.3%, respectively). In contrast, the 24-h absorbability of C22:0 in CAP was significantly less than that seen in PO (55.4%). Finally, there was no evidence of significant rearrangement of the positions of fatty acids on glycerol during digestion and absorption. Those fatty acids recovered in lymphatic fat tended to occupy the same glyceride positions that they did in the neat administered oils. However, the lymph fats recovered from all animals dosed with fat emulsions were enriched with endogenous lymph fatty acids. It is concluded that CAP is qualitatively digested, absorbed, and processed like any dietary fat or oil that contains medium-chain and very long-chain fatty acids.

Renewable Long-Chain Fatty Acids for Production of Biodegradable Medium-Chain-Length Polyhydroxyalkanoates (mcl-PHAs) at Laboratory and Pilot Plant Scales

2000 ◽  
Vol 33 (13) ◽  
pp. 4690-4698 ◽  
Author(s):  
Michele B. Kellerhals ◽  
Birgit Kessler ◽  
Bernard Witholt ◽  
Alexandre Tchouboukov ◽  
Helmut Brandl
Keyword(s):  
Fatty Acids ◽  
Chain Length ◽  
Pilot Plant ◽  
Long Chain Fatty Acids ◽  
Medium Chain ◽  
Medium Chain Length ◽  
Long Chain ◽  
Chain Fatty Acids
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