DPA: An Up-and-Coming Fatty Acid

by Alex Byelashov

Omega-3 fatty acids continue to be some of the most-researched nutrients for human health and nutrition. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are at the forefront of this research, as well as consumer awareness. However, docosapentaenoic acid (DPA), an elongated version of EPA, is starting to gain recognition in the scientific community for its role in improving human health, particularly in controlling inflammation. In order to get to know DPA, it is important to understand the unique benefits it can deliver that EPA and DHA cannot.

What is unique about DPA?

• DPA inhibits platelet aggregation more efficiently than EPA or DHA, meaning it hinders the formation potentially of deadly blood clots

• It is a precursor for oxylipins, anti-inflammatory and neuroprotective compounds

• DPA stimulates endothelial cell migration much more efficiently than EPA, meaning a stronger protection from atherosclerotic diseases such as coronary heart disease

• It is incorporated into phospholipids faster than EPA, meaning the fatty acids can cross the blood barrier and be utilized by the body more efficiently

In a study conducted by the Institute of Public Health and Clinical Nutrition, University of Eastern Finland, blood levels of DPA, a marker for DPA consumption, had the strongest association with healthy C-reactive protein (CRP) levels in middle-aged men when compared to other omega-3s such as EPA and DHA.

What does that mean for DPA and its role in inflammation?

DPA has a more direct biological role in the inhibition of cyclooxygenase, an enzyme that produces the prostaglandin hormones that sparks inflammation. Although it is widely accepted that EPA helps to control inflammation, a recent study conducted by the University of San Diego showed that in the body, EPA must be first elongated to DPA to take action. The authors stimulated mouse microphages with fatty acids to produce an inflammatory response. They reported that omega-3s affected eicosanoid signaling and inhibited COX. Among other findings, they demonstrated that DPA was responsible for COX inhibition after EPA supplementation, offering fresh insights into how 20-carbon EPA exerts anti-inflammatory effects indirectly through elongation to 22-carbon DPA, and that DPA is likely a major source of inhibition.

If EPA converts into DPA, doesn’t it make sense to just continue to formulate with EPA?

Although EPA has a great track record, studies show that even in optimal conditions, an appreciable amount of EPA is lost during the conversion to DPA. In addition, the conversion can be negatively influenced by other factors such as levels of omega-6 fatty acids in the diet, lifestyle choices (e.g. alcohol, smoking), other dietary compounds (e.g. enzyme co-factors) and genetic factors. Therefore formulating with DPA allows consumers to reap its maximum health benefits. 

Besides its ability to manage inflammation, what else are scientists uncovering about DPA?

Many studies have demonstrated supplementation with omega-3s provides protection from neural injuries. However, in a recently published study, a multi-national research team took an interesting approach. They used transgenic mice that were engineered to carry a gene that encodes an enzyme that converts omega-6 to omega-3. The study showed that the spinal cord damage of mice was less severe in transgenic mice than in the regular mice. Interestingly, the concentration of DPA remained significantly increased in the spinal cord of transgenic mice compared with the normal mice. The authors suggested that increased content of omega-3 DPA might contribute to the neuroprotective effect against spinal cord injury.

A new study from Harvard published in the Annals of Internal Medicine and funded by the National Institute of Health showed that higher levels of omega-3s, including DPA, are associated with lower total mortality, especially incidents of coronary heart disease death in the elderly.  

The profile of DPA is on the rise and the scientific community is validating its role as a distinct and powerful nutritional and therapeutic supplement.   

Alex Byelashov, Ph.D., M.P.H., is the manager of research and development at Omega Protein Corp .  He holds a doctorate in food science/safety from Colorado State University, and master's degrees from Iowa State University and Yale University's School of Public Health. Byelashov has authored/co-authored multiple research papers, press articles, scientific reports and book contributions, and serves as an active member of the Global Organization for EPA and DHA ( GOED ) scientific committee. 

References

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