Omega-3 fatty acid reduced disease severity in MS mouse model

Study findings could lead to new solutions in managing MS symptoms

by Marisa Wexler, MS | February 16, 2023

Treatment with docosahexaenoyl ethanolamide (DHEA), an omega-3 fatty acid found in fish oil, reduced inflammation and disease severity in a mouse model of multiple sclerosis (MS).

These findings suggest that “an increase of omega-3 consumption may be beneficial to patients diagnosed with MS,” researchers said.

“We believe our findings could lead to the discovery of new solutions to aid in managing symptoms of multiple sclerosis and other chronic inflammatory diseases like diabetes,” Aditi Das, PhD, said in a press release from the American Society for Biochemistry and Molecular Biology. Das is a professor at Georgia Tech University and co-author of the study.

The study, “Role of omega-3 endocannabinoids in the modulation of T-cell activity in a multiple sclerosis experimental autoimmune encephalomyelitis (EAE) model,” was published in the Journal of Biological Chemistry.

The role of diet in MS is complex, and there is no particular special diet that is widely recommended for people with the disease. However, some studies have suggested that omega-3 fatty acids, a group of fat molecules commonly found in fish oil, may have anti-inflammatory properties.

In this study, a team of U.S. scientists investigated the potential anti-inflammatory effects of DHEA, one of the omega-3 fatty molecules common in fish oil supplements. Once inside the body, this fatty molecule is converted into “metabolites that are immunomodulatory and may be beneficial as a potential nutrition-based intervention in diseases with aberrant inflammatory responses such as MS,” the researchers wrote.

“Our goal was to use something that is naturally found in food and the human body to see if we can enhance it to reduce the disease severity in multiple sclerosis patients,” they added.

In a first series of test done using cells in dishes, the researchers explored the effects of DHEA treatment on T-cells, a type of inflammatory immune cell with a central role in MS.

High doses of DHEA

When these cells are activated, they produce pro-inflammatory signaling molecules to trigger an immune attack. However, treatment with high doses of DHEA reduced the production of these signaling molecules from activated T-cells.

T-cells can undergo different polarizations — programs of molecular activity that help to coordinate different types of immune responses. DHEA treatment reduced two polarizations called Th1 and Th17, both of which have been implicated in MS.

The researchers next tested the effects of DHEA treatment in mice with experimental autoimmune encephalitis (EAE), a common model of MS. In these experiments DHEA was administered via injection into the animals’ abdomens, rather than via dietary consumption.

Results showed that mice treated with DHEA were slower to develop symptoms than mice given an inactive vehicle. “These data suggest that the DHEA treatment decreased the severity of the disease,” the researchers wrote.

The researchers noted there were “responders” and “non-responders” to DHEA treatment among the individual mice. Specifically, in some of the DHEA-treated mice, there was significantly longer periods of remission between the induction of disease and later relapse, while others developed the disease at the same time as untreated mice.

Analyses of nervous system tissues from the treated mice indicated that, in line with the earlier data from cell experiments, DHEA treatment reduced the number of inflammatory T-cells in the mouse model.