Fish oil may dampen inflammatory response to high-fat, high-sugar diet

The new research has been 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 researchers as WD) is too high in sugar and fat. It has long been known that it can give rise to chronic low-level inflammation, which is postulated to figure in the development of many disease states, such as cardiovascular disease, obesity, diabetes and others. Long-term exposure to DEO causes innate immune cell reprogramming that promotes low-grade inflammation, the authors said.

The researchers were looking at some specific inflammatory cascades to see if higher levels of omega-3s could “Attenuating inflammatory phenotypes promoted by DEO, 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 such as cell proliferation, apoptosis, migration, senescence, autophagy and inflammation.

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

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

Wide range of fatty acids in the 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 the main polyunsaturated fatty acids. It also contained significant amounts of monounsaturated fatty acids, palmitoleic acid and oleic acid.

The researchers measured the presence of different species of ceramides in blood plasma, as well as their search in adipose tissue. Their results showed that the fish oil intervention significantly attenuated this response to the high-fat, high-sugar diet.

“Overall, n-3-PUFA enrichment of WD appears to act as an inhibitor of ceramide production, mitigating the negative effects of a high-fat diet and, in doing so, improving the profile and population immune cells, potentially improving overall health.Fish oil n-3PUFAs are safer than pharmacological agents and can be taken as supplements as well as through food, without requiring costly interventions” ,concluded the researchers.

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 by avoiding ceramide-mediated pathways
Authors: Camacho-Muñoz D, et al.

Rachel J. Bradford