Eicosapentaenoic acid

Eicosapentaenoic acid (EPA or also icosapentaenoic acid) is an omega-3 fatty acid. In physiological literature, it is given the name 20:5(n-3). It also has the trivial name timnodonic acid. In chemical structure, EPA is a carboxylic acid with a 20-carbon chain and five cis double bonds; the first double bond is located at the third carbon from the omega end.

EPA and its metabolites act in the body largely by their interactions with the metabolites of arachidonic acid; see Essential fatty acid interactions for detail.

EPA is a polyunsaturated fatty acid that acts as a precursor for prostaglandin-3 (which inhibits platelet aggregation), thromboxane-3, and leukotriene-5 groups (all eicosanoids).

Sources

It is obtained in the human diet by eating oily fish or fish oil—cod liver, herring, mackerel, salmon, menhaden and sardine. It is also found in human breast milk.

It is available from some non-animal sources—spirulina and microalgae. Microalgae are being developed as a commercial source.^[1] EPA is not usually found in higher plants, but it has been reported in trace amounts in purslane.^[2]

Clinical significance

The US National Institute of Health's MedlinePlus lists a large number of conditions in which EPA (alone or in concert with other ω-3 sources) is known or thought to be effective.^[3] Most of these involve its ability to lower inflammation.

Among omega-3 fatty acids, in particular EPA is thought to possess beneficial potential in mental conditions, such as schizophrenia.^[4][5] Several studies report an additional reduction in scores on symptom scales used to assess the severity of symptoms, when additional EPA is taken.

Recent studies have suggested that EPA may effect depression, and importantly, suicidaliy risk. One such study,^[6] took blood samples of 100 suicide-attempt patients and compared the blood samples to those of controls and found that levels of Eicosapentaenoic acid were significantly lower in the washed red blood cells of the suicide-attempt patients.

EPA has inhibitory effect on CYP2C9 and CYP2C19 hepatic enzymes. At high dose, it may also inhibit the activity of CYP2D6 and CYP3A4, important enzymes involved in drug metabolism.^[7]

See also

• Chlorella
• Cyanobacteria
• Docosahexaenoic acid
• List of omega-3 fatty acids
• Polyunsaturated fatty acids
• Snake oil

References

1. ^ Jess Halliday (12/01/2007). Water 4 to introduce algae DHA/EPA as food ingredient. Retrieved on 2007-02-09.
2. ^ Simopoulos, Artemis P (2002). "Omega-3 fatty acids in wild plants, nuts and seeds". Asia Pacific Journal of Clinical Nutrition 11 (s6): S163–S173. doi:10.1046/j.1440-6047.11.s.6.5.. Retrieved on 2007-02-09. 
3. ^ NIH Medline Plus. MedlinePlus Herbs and Supplements: Omega-3 fatty acids, fish oil, alpha-linolenic acid. Retrieved on February 14, 2006.
4. ^ Peet M, Brind J, Ramchand CN, Shah S, Vankar GK (2001). "Two double-blind placebo-controlled pilot studies of eicosapentaenoic acid in the treatment of schizophrenia". Schizophrenia Research 49 (3): 243–51. PMID 11356585. Retrieved on 2007-12-21. 
5. ^ Song C., Zhao S. Omega-3 fatty acid eicosapentaenoic acid. A new treatment for psychiatric and neurodegenerative diseases: a review of clinical investigations. University of Prince Edward Island, Department of Biomedical Sciences, AVC, 550 University Avenue, Charlottetown, PE, Canada. cai.song@nrc.gc.ca (Expert Opin Investig Drugs. 2007 Oct;16(10):1627-38.) Pub-Med
6. ^ Huan M, Hamazaki K, Sun Y, Itomura M, Liu H, Kang W, Watanabe S, Terasawa K, Hamazaki T. (2004). "Suicide attempt and n-3 fatty acid levels in red blood cells: a case control study in China.". Biological psychiatry 56 (7): 490-6. PMID 1540784. 
7. ^ Yao HT, Chang YW, Lan SJ, Chen CT, Hsu JT, Yeh TK (2006). "The inhibitory effect of polyunsaturated fatty acids on human CYP enzymes". Life Sci. 79 (26): 2432–40. doi:10.1016/j.lfs.2006.08.016. PMID 16978661. 

da:Icosapentaensyre

de:Eicosapentaensäure es:Ácido eicosapentaenoico fr:Acide éicosapentaènoïque nl:Eicosapentaeenzuur ja:エイコサペンタエン酸 pl:Kwas eikozapentaenowy sv:EPA (fettsyra)