Data from 84 people with a moderate risk of cardiovascular risk (because of their genetic profile) indicated that fish oil supplements for eight weeks were associated with reductions in markers of damage to the endothelium (the cells lining the blood vessels), and increases in markers of endothelial repair, according to findings published in the American Journal of Clinical Nutrition.
Moreover, the effects seemed to be independent of variations in a gene that codes for nitric oxide production. NO is a potent vasodilator and variations in the gene for endothelial nitric oxide synthase (eNOS) has previously been linked to an increase in the risk of cardiovascular disease.
“The current study showed, for the first time to our knowledge, that 8 [weeks of] supplementation with fish oil (containing 1.5 grams of long chain omega-3s per day) significantly increased numbers of circulating [endothelial progenitor cells (EPCs)] and decreased numbers of [endothelial microparticles (EMPs)], which suggested an improved endothelial maintenance and repair and reduced endothelial damage,” wrote the authors, led by Szu-Yun Wu.
Four decades of scientific support
The study adds to a large body of evidence supporting the potential cardiovascular benefits of omega-3s, first reported in the early 1970s by Dr Jorn Dyerberg and his co-workers in The Lancet and The American Journal of Clinical Nutrition.
To date, the polyunsaturated fatty acids (PUFAs) have been linked to improvements in blood lipid levels, a reduced tendency of thrombosis, blood pressure and heart rate improvements, and improved vascular function.
However, the improvements in endothelial health reported by the Reading-based scientists were not accompanied by improvements in vascular function.
Wu and her co-workers recruited 84 people with moderate CVD risk to participate in their randomized, double-blind, placebo-controlled, crossover trial. Participants were randomly assigned to receive either placebo or fish oil supplements providing a daily omega-3 dose of 1.5 grams (0.9 grams of EPA and 0.6 grams of DHA in the triacylglycerol form. The fish oil supplements were provided by EPAX). This was followed by an eight week ‘washout period’ before they were crossed over to the other intervention group.
Results showed that EPC numbers increased by an average of 126.5 in the fish oil group, compared with only 5.17 in the placebo group. In addition, EMP numbers decreased by an average of 8.75 in the fish oil group, compared with a 2.74 decrease in the placebo group.
Commenting on the study’s findings, Harry Rice, PhD, VP of regulatory and scientific affairs for the Global Organization for EPA and DHA Omega-3s (GOED), told us: “Now that it has been demonstrated in vivo that EPA and DHA impact EPCs and EMPs, putative indicators of endothelial function, the question is whether or not the results can be replicated. Assuming they are replicated, then it will be time to determine scientific, as well as clinical relevance.”
Source: American Journal of Clinical Nutrition
Published online ahead of print, doi:10.3945/ajcn.114.088880
“Fish-oil supplementation alters numbers of circulating endothelial progenitor cells and microparticles independent of eNOS genotype”
Authors: S-Y. Wu, J. Mayneris-Perxachs, J.A. Lovegrove, S. Todd, P. Yaqoob