Docosahexaenoate-enriched fish oil and medium chain triglycerides shape the feline plasma lipidome and synergistically decrease circulating gut microbiome-derived putrefactive postbiotics

Abstract

The purpose of this study was to examine the influence of medium-chain fatty acid-containing triglycerides (MCT), long-chain polyunsaturated fatty acid-containing triglycerides, and their combination on the plasma metabolome of cats (Felis catus), including circulating microbiome-derived postbiotics. After a 14-day lead-in on the control food, cats were randomized to one of four foods (control, with 6.9% MCT, with fish oil [FO; 0.14% eicosapentaenoate, 1.0% docosahexaenoate], or with FO+MCT; n = 16 per group) for 28 days. Analysis of plasma metabolites showed that the addition of FO and MCT led to synergistic effects not seen with either alone across a number of lipid classes, including fatty acids, acylcarnitines, and acylated amines including endocannabinoids. Notably, the FO+MCT group had an increase in ketone body production relative to baseline and beyond that seen with MCT alone. N-acyl taurines, the accumulation of which has been implicated in the onset of type 2 diabetes, were significantly decreased in the FO+MCT group. Significant decreases in the gut microbiome-derived postbiotic classes of indoles/indolic sulfates and phenols/phenolic sulfates were observed only the FO+MCT group. Overall, the combination of MCT and FO led to number of changes in plasma metabolites that were not observed with either oil alone, particularly in postbiotics.

Dietary Fatty Acids Change Circulating Fatty Acids, Microbial Putrefactive Postbiotics and Betaine Status in the Cat

“…Changes in the fatty acid composition of glycosylphosphatidylinositols, phosphatidylethanolamines and sphingomyelins were both expected and observed. The reduction in cholesterol in response to dietary E&D is similar to what we have shown previously [6] so this seems to be a repeatable finding in cats which appears to be different than that seen in humans [31,32]. This suggests that supplementary dietary E&D could be of value for a food designed to aid in the management of feline hypercholesterolemia.…”

“…This (with the exception of 4-vinylphenol sulfate) was not the result of a reduction during the time of E&D consumption but rather because the concentration change was significantly lower than the change in the control group. Our previous study detected changes in circulating microbiome putrefactive postbiotics of the phenol and indole classes, however that study utilized DHA-enriched fish oil (DHA:EPA ratio = 7.3) and cats were fed for only 4 weeks rather than the DHA:EPA ratio in the current study of 0.56 with a 12 week feeding period [6]. The changes in phenols in that study included both decreases (3) and increases (4) in response to the increased PUFA, and increases in five indoles including indoleacetate and indolepropionate; none of these changed significantly in the current study which may indicate nuance in the responsiveness of the gut microbiome to EPA versus DHA or that length of feeding results in differential conditioning of the microbiome.…”

“…Clinical blood chemistry and circulating fatty acids were completed at the times of metabolomic analysis and after 56 days of eating one of the test foods. A COBAS c501 module (Roche Diagnostics Corporaion, Indianapolis, IN, USA) was used for clinical blood chemistry analysis and Metabolon (Morrisville, NC, USA) performed the metabolomics analysis of the plasma as previously described [6,27]. In short, the samples were processed with a proprietary methanol based solvent extract.…”

“…The microbiome is known to influence its host through metabolites which it produces (postbiotics) and it has been shown that this influence responds to dietary lipids in the cat [6]. These postbiotics can be absorbed in the colon and into the host circulation of cats, mice and humans [6][7][8].…”

“…The microbiome is known to influence its host through metabolites which it produces (postbiotics) and it has been shown that this influence responds to dietary lipids in the cat [6]. These postbiotics can be absorbed in the colon and into the host circulation of cats, mice and humans [6][7][8]. The consumption of E&D has been shown to change the gut microbiome through altering the abundance of microbiota which are known to be involved with specific physiological conditions [9,10].…”