Understanding how omega-3 dampens inflammatory reactions

August 23, 2017, Norwegian University of Science and Technology

Omega-3 fatty acids, which we primarily get through eating fatty fish, have long been thought to be good for our health. Many dietary studies have suggested that high intake is associated with a reduced risk of various disorders. Clinical trials have also shown beneficial anti-inflammatory effects in patients taking omega-3 supplements.

Recent research from NTNU supports previous discoveries, and has also found new, useful effects of omega-3 supplements and how these lipids dampen harmful inflammatory reactions in the body.

Effects little known

Despite numerous published dietary and clinical studies, we still don't fully understand how omega-3 fatty acids affect our cells and if this varies from person to person, between healthy and ill individuals, or whether the mechanism of action varies in different tissues and cells. What we are most sure of is that omega-3 fatty acids can dampen inflammatory reactions. Inflammatory reactions are very important in combating infections, but they can be harmful if activated too strongly or in the absence of bacteria and viruses, like in autoimmune diseases and organ transplants.

Macrophages, which are immune cells that live in all tissues and organs, play a key role in coordinating inflammatory reactions in the body and monitor everything that happens in our tissues. The convert the information they obtain through various sensors or receptor on their surface to secretion of various hormone-like signal substances that control all parts of inflammatory reactions.

Inflammation can be harmful

We have increasingly become aware that macrophages can be more or less potent in activating inflammatory reactions. So-called sterile inflammatory reactions, such as , are often directly harmful.

The ability of macrophages to stimulate inflammatory reactions depends on processes within the macrophage.

Autophagy is one of the processes within macrophages that is important for whether a macrophage is calm or hyperactive. Autophagy (meaning "self-eating") is a key process for degradation of dysfunctional or unnecessary proteins and other components within our cells.

In the last few years, we've learned a lot about how important this process is, say the researchers. The Nobel Prize in Physiology or Medicine 2016 was given to Yoshinori Ohsumi for his discovery of the key genes that control .

Autophagy is constantly going on in all cells and increases if the cells are starving or injured. We hypothesized that omega-3 fatty acids could dampen inflammatory reactions by elevating autophagy in macrophages. If so, we surmised that this effect might change the signal transformation in the macrophage and as a result, suppress activation of inflammatory reactions.

Activates self-cleaning process

By studying macrophages isolated from mice and humans, we found that the omega-3 fatty acids activated the autophagy and specifically affected some proteins that transform the signals from the environment. Furthermore, we found that omega-3 fatty acids dampened many inflammatory mechanisms within the macrophages, but especially reduced what is known as the type 1 interferon response.

The factor CXCL-10, which macrophages secrete as part of this interferon response following many types of stimuli, was the most clearly reduced factor after adding omega-3 to the cells.

We then examined blood samples from a clinical study in cardiac transplant patients where we knew that improved their clinical status. In these cases, we found that omega-3 fatty acids reduced the level of CXCL-10.

Supplements beneficial

Autophagy thus changes in macrophages in response to omega-3 fatty acids and specifically inhibits the secretion of inflammatory factors that belong to the interferon response, with CXCL-10 showing the clearest reduction. The results of this study are being published in the journal Autophagy.

These findings indicate that supplements may be particularly beneficial in patients who have conditions that are driven or aggravated by a strong interferon response and CXCL-10.

Our research group hopes that this one day will benefit patients with different forms of cancer, meningitis, multiple sclerosis, Alzheimer's disease or jaundice. But we must emphasize that a lot of work remains.

Explore further: Omega-3 fatty acids fight inflammation via cannabinoids

More information: Jennifer Mildenberger et al. N-3 PUFAs induce inflammatory tolerance by formation of KEAP1-containing SQSTM1/p62-bodies and activation of NFE2L2, Autophagy (2017). DOI: 10.1080/15548627.2017.1345411

Related Stories

Omega-3 fatty acids fight inflammation via cannabinoids

July 18, 2017
Chemical compounds called cannabinoids are found in marijuana and also are produced naturally in the body from omega-3 fatty acids. A well-known cannabinoid in marijuana, tetrahydrocannabinol, is responsible for some of its ...

Study finds new link between omega fatty acids and bowel cancer

June 28, 2017
A study by the University of Aberdeen has found that a higher concentration of the molecules that breakdown omega-3 fatty acids is associated with a higher chance of survival from bowel cancer.

Omega-3 fatty acid supplementation may treat autoimmunity in type 1 diabetes

April 4, 2017
Type I diabetes (T1D) is an autoimmune condition that develops after the immune system attacks and destroys pancreatic β cells, leading to impaired insulin production. Currently, no therapies can successfully reverse the ...

Diets rich in omega-3 fatty acids may help lower blood pressure in young, healthy adults

November 14, 2016
Healthy young people may be able to help prevent the onset of high blood pressure by eating diets rich in omega-3 fatty acids, according to a preliminary study presented at the American Heart Association's Scientific Sessions ...

Omega-3 dietary supplements pass the blood-brain barrier

December 4, 2013
(Medical Xpress)—New research from Karolinska Institutet shows that omega-3 fatty acids in dietary supplements can cross the blood brain barrier in people with Alzheimer's disease, affecting known markers for both the disease ...

Recommended for you

Drinking may worsen hearing loss at loud concerts

April 19, 2018
(HealthDay)—High-decibel music blasting at big concert venues is a known cause of short-term hearing loss. But new research suggests drinking doesn't help matters, with drunk concertgoers actually moving closer to loudspeakers.

Age affects how we predict and respond to stress at home

April 19, 2018
A recent study finds that older adults are better than younger adults at anticipating stressful events at home - but older adults are not as good at using those predictions to reduce the adverse impacts of the stress.

Low total testosterone in men widespread, linked to chronic disease

April 19, 2018
A male's total testosterone level may be linked to more than just sexual health and muscle mass preservation, a new study finds. Low amounts of the hormone could also be associated with chronic disease, even among men 40 ...

Low-cost anti-hookworm drug boosts female farmers' physical fitness

April 19, 2018
Impoverished female farm workers infected with intestinal parasites known as hookworms saw significant improvements in physical fitness when they were treated with a low-cost deworming drug. The benefits were seen even in ...

What happens to our muscles during spaceflight and when living on Mars?

April 17, 2018
The inactivity of astronauts during spaceflights presents a significant risk to their muscles, says a new study in The Journal of Physiology. Scientists have simulated the impact of 21 day spaceflights on the body, and the ...

Parental diet before conception affects child's health

April 17, 2018
A child's health can be compromised not only by a mother who smokes or drinks during pregnancy, but by the obesity and poor diet of both parents well before the act of procreation, researchers said Tuesday.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.