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  • Researchers investigated the effects of omega-3 fatty acid supplementation on mouse models of multiple sclerosis (MS).
  • They found that higher doses of omega-3 reduce the onset of MS, increase the time to relapse, and reduce symptom severity.
  • Further research is needed to confirm the results.

Multiple sclerosis (MS) is a chronic condition in which the immune system attacks the fatty layer that’s known as the myelin sheath surrounding nerves. This, in turn, reduces the ability of nerves to carry signals.

Symptoms of MS include vision problems, tremors, and emotional changes. While the cause of the condition may vary across patients, it is thought to arise from an inflammatory response.

While a link exists between omega-3 fatty acid consumption and improved quality of life among patients with MS, the underlying mechanisms remain unknown.

Some studies show that diets rich in omega-3 fatty acids are linked to lower MS rates and have beneficial anti-inflammatory and neurological health properties.

Recently, researchers investigated how omega-3 fatty acid consumption reduces inflammatory responses in mice.

They found that docosahexaenoyl ethanolamide (DHEA), a lipid compound derived from docosahexaenoic acid (DHA) found in fish oil, may reduce immune T cell responses and thus reduce MS-related inflammation.

Beata Rydyger, BSc, RHN, Registered Nutritionist based in Los Angeles, CA, not involved in the study, told Medical News Today:

“DHEA has been shown to have immune-regulating properties, and at certain concentrations, be able to significantly suppress the production of monocyte chemotactic protein-1 (MCP-1), a cytokine that plays a pivotal role in chronic inflammation associated with autoimmune disease, including MS. This study found that DHEA might also inhibit T-cell responses- another important precursor to MS.”

The corresponding study appears in the Journal of Biological Chemistry.

To begin, the researchers observed how DHEA influenced T-cell responses in cells isolated from mice. They found that DHEA reduced inflammatory markers when taken at a high dose. DHEA also reduced the percentage of pathogenic T cells.

Next, the researchers investigated whether MS disease progression influences DHEA levels in mice. They found that during the MS progression, DHEA levels vary in the spinal cord and spleen but not the brain.

In particular, they found that DHEA levels are at their highest concentration in mice when in remission from MS, indicating that DHEA may dampen inflammation linked to the condition.

The researchers next sought to treat mouse models of MS with DHEA. While low doses of 5 mg/ kg per day had no effect, 100 mg/ kg per day belated the onset of the condition, delayed relapse, and reduced severity scores.

From further experiments, they found that mice who were treated with DHEA had fewer inflammatory markers than controls.

The results, noted the researchers, indicate that DHEA likely reduces inflammation and, thus MS symptoms by reducing number of pathogenic T cells in the nervous system.

They further noted that treatment with DHEA did not affect the immune response of healthy mice. They wrote that this suggests DHEA influences the immune response outside of the brain in mice with MS, and not in healthy mice.

The researchers concluded that DHEA may reduce the severity of MS and thus may be added to diets to complement existing treatments for the condition.

When asked about the study’s limitations, Rydyger told MNT that the researchers conducted the study in mice, not humans. She noted that this means the findings will need to be confirmed in clinical tests on humans before arriving at conclusions.

Dr. J. William Lindsey, neurologist with UTHealth Houston and Memorial Hermann, not involved in the study, also told MNT:

“The effects of DHEA in the mice were small, and the effects on cultured cells were complex. DHEA gets metabolized to multiple other molecules, and it is not certain which metabolite has the desired activity.”

Dr. Lindsey added that although there has been interest in the potential for omega-3 to treat neurodegenerative for some time, few have been rigorous.

“The only rigorous study that I know of, published in 2012, did not show a clinical benefit of omega-3 fatty acids for MS. The effects of DHEA need further investigation, and it is possible that one of the metabolites identified by these investigators will be beneficial. For now, people with MS should pursue a heart-healthy or Mediterranean diet,” he explained.

Dr. Siddharth Kharkar, a neurologist in Thane, India, not involved in the study, told MNT:

“The 100 mg/kg DHEA dose utilized in this study translates into a 6000 mg or 6 gm dose of DHEA for a 60 kg human. Most preparations of DHEA in the market are 100 mg/tablet. Taking an equivalent dose would mean taking 60 tablets of such a preparation in one go. Besides being impractical, taking such a high dose could lead to extremely serious side effects.”

MNT spoke with Dr. Barbara Giesser, neurologist and MS specialist at Pacific Neuroscience Institute at Providence Saint John’s Health Center in Santa Monica, CA, about the implications of the research.

Dr. Giesser noted previous studies suggested that consuming omega-3 fatty acids reduces MS risk, and that omega-3 fatty acids reduce levels of inflammatory proteins in those with MS and improve some symptoms. She said, however, that further research is needed to confirm the results.

Dr. Kharkar also cautioned: “It remains to be seen how the efficacy of DHEA compares against currently available MS treatments. Also, the long-term effect of DHEA- a steroid- on the human body is unknown. Other steroids- glucocorticoids such as prednisolone are commonly used for other autoimmune diseases- are associated with osteoporosis and recurrent infections if taken at a high dose for a long time.”

“For these reasons, I would not recommend supplementation (DHEA in addition to medications) and very strongly advise against substitution (DHEA instead of medications) for the treatment of MS, at the present time,” he noted.

Rydyger said: “The findings of this study offer a promising potential solution for lowering inflammation and alleviating symptoms for patients with MS. By consuming a diet rich in polyunsaturated fats like cold-water fish- such as salmon, mackerel, tuna, herring, and sardines- and fish oil supplements, patients with MS have the potential to improve their quality of life without hardly any side-effects.”

“The research is also a gateway for the discovery of new solutions and innovations for managing symptoms of MS and other chronic inflammatory diseases like diabetes,” she concluded.