Nutrigenomics explains omega-3's immune health benefits
By Stephen Daniells, 30-Jul-2009

Related topics: Omega-3, Research, Nutritional lipids and oils,
Cardiovascular health, Immune system

Omega-3-rich fish oil beneficially affects gene expression, says a new
nutrigenomic study that enhances our understanding of the health benefits of
omega-3.

The study is said to be the first to show that DHA (docosahexaenoic acid)
and EPA (eicosapentaenoic acid) can affect gene expression to a more
anti-atherogenic and anti-inflammatory status.

Lead researcher Lydia Afman told NutraIngredients: "The most exciting
finding of this study is the demonstration of less pro-inflammatory gene
expression profiles in peripheral blood mononuclear cells (PBMCs) after a 6
months fish oil intervention in a healthy elderly population."

Because PBMCs are immune cells, and play a vital role in inflammation and
the development of cardiovascular diseases, the results may go some way to
explaining the cardio-protective effects of omega-3 fatty acids.

In addition to a large body of science linking DHA and EPA to improved
cardiovascular health, the omega-3 fatty acids have also been linked to
reduced risks of certain cancers, good development of a baby during
pregnancy, improved joint health, and improved behaviour and mood

Results of the nutrigenomics study are published in the American Journal of
Clinical Nutrition.

Study details

Dr Afman and her co-workers from the Nutrition, Metabolism and Genomics
Group at Wageningen University recruited 111 healthy Dutch elderly subjects
and randomly assigned them to one of three groups: To consume 1.8 or 0.4 g
of EPA plus DHA every day (Lipid Nutrition/Loders Croklaan), or to consume
4.0 grams of high-oleic acid sunflower oil per day, for six months.

Microarray analysis of gene expression in PBMCs revealed that that high EPA
plus DHA supplement resulted in altered gene expression of 1040 genes, while
the sunflower oil supplement altered gene expression of 298 genes.

"Of these genes, 140 were overlapping between the groups, which resulted in
900 uniquely changed genes in the EPA plus DHA group," said the researchers.

Furthermore, the altered genes were involved in inflammatory- and
atherogenic-related pathways, said the researchers.

"These results are the first to show that intake of EPA plus DHA for 26
weeks can alter the gene expression profiles of PBMCs to a more
anti-inflammatory and anti-atherogenic status," concluded the researchers.

Atherosclerosis, or hardening of the arteries, is a major risk factor for
CVD.

Implications for nutrigenomics

Dr Afman told this website: "PBMC gene expression profiles are known to be
quite constant within persons but vary between persons in time. Therefore,
it is interesting to observe that PBMCs gene expression profiles are
susceptible to nutritional changes and represent effects that maybe
difficult or even impossible to measure using other techniques.

"PBMC gene expression profiles are therefore promising candidates to be used
as biomarkers for nutritional status or systemic metabolic health or -
capacity."

Source: American Journal of Clinical Nutrition
Volume 90, pages 415-424, doi: 10.3945/ajcn.2009.27680
"Fish-oil supplementation induces antiinflammatory gene expression profiles
in human blood mononuclear cells"
Authors: M. Bouwens, O. van de Rest, N. Dellschaft, M. Grootte Bromhaar,
L.C.P.G.M. de Groot, J.M. Geleijnse, M.Muller, L.A. Afman

Mike V