Fish oil may blunt inflammatory response to high fat/high sugar diet

The new research was published in the journal Biochemical Pharmacology​.  It was the work of researchers associated with universities and research institutes in London and Manchester in the UK.

Western diet causes chronic inflammation

The typical Western diet (abbreviated by the researchers as WD) is overly rich in sugar and fats.  It has long been known that it can give rise to chronic low level inflammation, which, it is postulated, figures into the development of many disease states, such as cardiovascular disease, obesity, diabetes and others.   Long term exposure to WD causes a reprogramming of innate immune cells that fosters the low grade inflammation, the authors said.

The researchers were looking some specific inflammatory cascades to see if higher levels of omega-3s could “attenuate inflammatory phenotypes promoted by WD, through ceramide-dependent pathways.”​

Ceramides belong to a class of lipid signaling molecules called sphingolipids, named after the ancient Sphinx because of their enigmatic nature. They are involved in biological processes including cell proliferation, apoptosis, migration, senescence, autophagy and inflammation.

The researchers used wild-type mice as their investigational model.  The animals were divided into three groups, one of which ate a standard chow diet as a control.  The other two groups at a high fat diet or a high fat diet that was supplemented with 5% menhaden oil. 

 The two high fat diets were adjusted to have equal total energy and total fats and sugars, with both being about 40% fat, as compared to the chow diet, which was about 9% fat. In addition the two high fat diets were also high in sugar, with about 34% of the energy coming from sucrose, as compared to about 4% in the standard chow.  The animals ate the diets for 21 days.

Wide array of fatty acids in diet

The menhaden oil enriched diet provided about 1.5% of total calories as omega-3 fatty acids.  The menhaden oil  used contained EPA, DHA and SDA as its primary polyunsaturated fatty acids. It also contained significant amounts of the monounsaturated fatty acids palmitoleic acid and oleic acid.

The researchers measured the presence of the various ceramide species in blood plasma, as well as looking for them in adipose tissue.  Their results showed that the fish oil intervention significantly blunted this response to the high fat/high sugar diet.

“Overall, n-3-PUFA enrichment of WD appears to act as ceramide production inhibitor, attenuating the negative effects of a diet high in fat, and in doing so, improve the profile and population of immune cells, potentially ameliorating overall health. Fish oil n-3PUFA are safer than pharmacological agents and can be taken as supplements but also through foods, without the need for expensive interventions,”​ the researchers concluded.

Source: ​Biochemical Pharmacology​​​
doi.org/10.1016/j.bcp.2022.115211 Epub ahead of print.
Omega-3 polyunsaturated fatty acids reverse the impact of western diets on regulatory T cell responses through averting ceramide-mediated pathways​
Authors: Camacho-Muñoz D, et al.