Eicosapentaenoic acid

Eicosapentaenoic acid, EPA, the eicosapentaenoic acid is an essential polyunsaturated C20:5 (ω-3) fatty acid, with the molecular formula C20H30O2, which belongs to the class of omega-3 fatty acids (Note: the spelling "C20:5 (ω-3)" for the lipid name means that the acid contains 20 C atoms and has 5 double bonds. ω-3 means that starting from the methyl end, the first double bond is on the 3rd carbon atom).

The eicosapentaenoic acid is a colourless oil. The eicosapentaenoic acid is needed for many functions of the metabolism. It is the starting material for the formation of docosahexaenoic acid (DHA) and the eicosanoids. Its biosynthesis takes place in the human organism via the alpha-linolenic acid (C18: 3ω-3), an essential C18 omega-3 fatty acid, which occurs in linseed oil, for example.

It has been shown that about 5-10% of the alpha-linolenic acid absorbed is converted into eicosapentaenoic acid (EPA) and 2-5% into docosahexaenoic acid (DHA). However, plasma levels of omega-3 fatty acids are not only controlled by the nutritive uptake of the fatty acids, but also by polymorphisms of genes coding for fatty acid desaturase 1-3. These enzymes convert short-chain fatty acids (e.g. alpha-linolenic acid) into long-chain unsaturated fatty acids (Davidson MH 2013).

Eicosapentaenoic acid, like other unsaturated fatty acids, is used in cosmetic formulations as a skin care product and as an emollient (makes the skin smooth and supple).

Omega-3 fatty acids, especially eicosapentaenoic acid, are ubiquitously distributed. They are mainly found in cold-water fish (herring, salmon) and the fish oils produced from them. The animal organism cannot change an omega-3 fatty acid from the methyl end and thus cannot metabolize this area either.

The highly unsaturated fatty acids such as arachidonic acid (C20:5 4ω-6) and eicosapentaenoic acid (C20: 5ω-3) are parent substances of the icosanoids (prostaglandins, thromboxanes, leukotrienes). For the production of eicosapentaenoic acid, fish oil is prepared from fish waste from fatty sea fish. As an alternative to fish oil preparations, purely vegetable omega-3 preparations derived from algae have been available for some time.

A lack of essential fatty acids may lead to inflammatory skin changes. Controversial is the, frequently propagated, prophylactic oral use of unsaturated fatty acids for the prevention of coronary heart disease (Ohnishi H et al. 2013; Sato T et al. 2014), for the improvement or prophylaxis of atopic eczema (Amagai Y et al. 2015, Kaczmarski M et al. 2013) or for neurological diseases. In larger studies, an antihypertensive effect could be demonstrated by the intake of eicosapentaenoic acid and docosahexaenoic acid (DHA) (Miller PE et al. 2014).

1. Amagai Y et al (2015) Dihomo-γ-linolenic acid prevents the development of atopic dermatitis through prostaglandin D1 production in NC/Tnd mice. J Dermatol Sci 79:30-37.
2. Davidson MH (2013) Omega-3 fatty acids: new insights into the pharmacology and biology of docosahexaenoic acid, docosapentaenoic acid, and eicosapentaenoic acid. Curr Opin Lipidol 24:467-474.
3. Burger A et al (1993) Hunnius Pharmaceutical Dictionary 7th Edition Walter de Gruyter Berlin-New York p. 544
4. Kaczmarski M et al (2013) Supplementation with long chain polyunsaturated fatty acids in treatment of atopic dermatitis in children. Postepy Dermatol Alergol 30:103-107.
5. Miller PE et al (2014) Long-chain omega-3 fatty acids eicosapentaenoic acid and docosahexaenoic acid and blood pressure: a meta-analysis of randomized controlled trials. At J Hypertens 27:885-896.
6. Ohnishi H et al (2013) Eicosapentaenoic acid (EPA) reduces cardiovascular events: relationship with the EPA/arachidonic acid ratio. J Atheroscler Thromb 20:861-877.
7. Sato T et al(2014)Effects of eicosapentaenoic acid treatment on epicardial and abdominal visceral adipose tissue volumes in patients with coronary artery disease. J Atheroscler Thromb 21:1031-1043.