Eicosapentaenoic acid

Source: Wikipedia, the free encyclopedia.
For other uses, see EPA (disambiguation).
Eicosapentaenoic acid
Eicosapentaenoic acid
Names
Preferred IUPAC name
(5Z,8Z,11Z,14Z,17Z)-Icosa-5,8,11,14,17-pentaenoic acid
Other names
(5Z,8Z,11Z,14Z,17Z)-5,8,11,14,17-eicosapentaenoic acid
Identifiers
3D model (
JSmol
)
3DMet
1714433
ChEBI
ChEMBL
ChemSpider
DrugBank
ECHA InfoCard
 100.117.069 Edit this at Wikidata
IUPHAR/BPS
KEGG
UNII
  • InChI=1S/C20H30O2/c1-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16-17-18-19-20(21)22/h3-4,6-7,9-10,12-13,15-16H,2,5,8,11,14,17-19H2,1H3,(H,21,22)/b4-3-,7-6-,10-9-,13-12-,16-15- checkY
    Key: JAZBEHYOTPTENJ-JLNKQSITSA-N checkY
  • InChI=1/C20H30O2/c1-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16-17-18-19-20(21)22/h3-4,6-7,9-10,12-13,15-16H,2,5,8,11,14,17-19H2,1H3,(H,21,22)/b4-3-,7-6-,10-9-,13-12-,16-15-
    Key: JAZBEHYOTPTENJ-JLNKQSITBZ
  • O=C(O)CCC\C=C/C\C=C/C\C=C/C\C=C/C\C=C/CC
Properties
C20H30O2
Molar mass 302.451 g/mol
Hazards
GHS labelling:
GHS05: Corrosive
Danger
H314
P260, P264, P280, P301+P330+P331, P303+P361+P353, P304+P340, P305+P351+P338, P310, P321, P363, P405, P501
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)

Eicosapentaenoic acid (EPA; also icosapentaenoic acid) is an

cis double bonds
; the first double bond is located at the third carbon from the omega end.

EPA is a

free fatty acid), a prescription drug containing only EPA, was shown to reduce heart attack, stroke, and cardiovascular death by 25% relative to a placebo in those with statin-resistant hypertriglyceridemia.[5][6]

Sources

EPA is obtained in the human diet by eating oily fish, e.g., cod liver, herring, mackerel, salmon, menhaden and sardine, various types of edible algae, or by taking supplemental forms of fish oil or algae oil. It is also found in human breast milk.

Fish, like most vertebrates, can synthesize very little EPA from dietary

Yarrowia lipolytica,[9] and from microalgae such as Nannochloropsis oculata, Monodus subterraneus, Chlorella minutissima and Phaeodactylum tricornutum,[10][11] which are being developed as a commercial source).[12] EPA is not usually found in higher plants, but it has been reported in trace amounts in purslane.[13] In 2013, it was reported that a genetically modified form of the plant camelina produced significant amounts of EPA.[14][15]

The human body converts a portion of absorbed

diabetes
or certain allergies may significantly limit the human body's capacity for metabolization of EPA from ALA.

Forms

Commercially available dietary supplements are most often derived from fish oil and are typically delivered in the triglyceride, ethyl ester, or phospholipid form of EPA. There is debate among supplement manufacturers about the relative advantages and disadvantages of the different forms. One form found naturally in algae, the polar lipid form, has been shown to have improved bioavailability over the ethyl ester or triglyceride form.[16] Similarly, DHA or EPA in the lysophosphatidylcholine (LPC) form was found to be more efficient than triglyceride and phosphatidylcholines (PC) in a 2020 study.[17]

Base EPA
Ethyl ester EPA ethyl ester
Lysophosphatidylcholine (LPC, or lysoPC) LPC-EPA, or lysoPC-EPA
Phosphatidylcholine (PC) EPA-PC
Phospholipid (PL) EPA-PL
Triglyceride (TG) or triacylglycerol (TAG) EPA-TG, or EPA-TAG
Re-esterified triglyceride (rTG), or re-esterified triacylglycerol (rTAG) EPA rTG, or r-TAG

Biosynthesis

Aerobic eukaryote pathway

EPA via aerobic eukaryote fatty acid synthesis

Aerobic eukaryotes, specifically microalgae, mosses, fungi, and most animals (including humans), perform biosynthesis of EPA usually occurs as a series of desaturation and elongation reactions, catalyzed by the sequential action of desaturase and elongase enzymes. This pathway, originally identified in Thraustochytrium, applies to these groups:[18]

  1. a desaturation at the sixth carbon of
    Δ6 desaturase to produce stearidonic acid
    (SDA, 18:4 ω-3),
  2. elongation of the stearidonic acid by a Δ6 elongase to produce eicosatetraenoic acid (ETA, 20:4 ω-3),
  3. desaturation at the fifth carbon of eicosatetraenoic acid by a Δ5 desaturase to produce eicosapentaenoic acid (EPA, 20:5 ω-3),

Polyketide synthase pathway

α-linolenic acid to EPA via PKS

Marine bacteria and the microalgae

PUFA to LC-PUFA is dependent on the fatty acyl desaturase and elongase enzymes. The molecule basis of the enzymes will dictate where the double bond is formed on the resulting molecule.[19]

The proposed polyketide synthesis pathway of EPA in Shewanella (a marine bacterium) is a repetitive reaction of reduction, dehydration, and condensation that uses acetyl coA and malonyl coA as building blocks. The mechanism of α-linolenic acid to EPA involves the condensation of malonyl-CoA to the pre-existing α-linolenic acid by KS. The resulting structure is converted by NADPH dependent reductase, KR, to form an intermediate that is dehydrated by the DH enzyme. The final step is the NADPH-dependent reduction of a double bond in trans-2-enoly-ACP via ER enzyme activity. The process is repeated to form EPA.[20]

Clinical significance

Further information: Essential fatty acid interactions
Salmon is a rich source of EPA.

The US

National Institute of Health's MedlinePlus lists medical conditions for which EPA (alone or in concert with other ω-3 sources) is known or thought to be an effective treatment.[21] Most of these involve its ability to lower inflammation
.

Intake of large doses (2.0 to 4.0 g/day) of long-chain omega-3 fatty acids as prescription drugs or dietary supplements are generally required to achieve significant (> 15%) lowering of triglycerides, and at those doses the effects can be significant (from 20% to 35% and even up to 45% in individuals with levels greater than 500 mg/dL).

Dietary supplements containing EPA and DHA lower triglycerides in a dose dependent manner; however, DHA appears to raise

LDL-C values (a measurement/estimate of the cholesterol mass within LDL-particles), while EPA does not. This effect has been seen in several meta-analyses that combined hundreds of individual clinical trials in which both EPA and DHA were part of a high dose omega-3 supplement, but it is when EPA and DHA are given separately that the difference can be seen clearly.[22][23] For example, in a study by Schaefer and colleagues of Tufts Medical School, patients were given either 600 mg/day DHA alone, 600 or 1800 mg/day EPA alone, or placebo for six weeks. The DHA group showed a significant 20% drop in triglycerides and an 18% increase in LDL-C, but in the EPA groups modest drops in triglyceride were not considered statistically significant and no changes in LDL-C levels were found with either dose.[24]

Ordinary consumers commonly obtain EPA and DHA from foods such as fatty fish,[a] fish oil dietary supplements,[b] and less commonly from algae oil supplements[c] in which the omega-3 doses are lower than those in clinical experiments. A Cooper Center Longitudinal Study that followed 9253 healthy men and women over 10 years revealed that those who took fish oil supplements did not see raised LDL-C levels.[25] In fact, there was a very slight decrease of LDL-C which was statistically significant but too small to be of any clinical significance. These individuals took fish oil supplements of their own choosing, and it should be recognized that the amounts and ratios of EPA and DHA vary according to the source of fish oil.

Omega-3 fatty acids, particularly EPA, have been studied for their effect on

autistic spectrum disorder (ASD). Some have theorized that, since omega-3 fatty acid levels may be low in children with autism, supplementation might lead to an improvement in symptoms. While some uncontrolled studies have reported improvements, well-controlled studies have shown no statistically significant improvement in symptoms as a result of high-dose omega-3 supplementation.[26][27]

In addition, studies have shown that omega-3 fatty acids may be useful for treating depression.[28][29]

EPA and DHA

ethyl esters (all forms) may be absorbed less well, thus work less well, when taken on an empty stomach or with a low-fat meal.[30]

Notes

  1. ^ Cooked salmon contain 500–1,500 mg DHA and 300–1,000 mg EPA per 100 grams of fish. See page: Salmon as food.
  2. ^ Omega-3 dietary oil supplements have no standard doses and generally salmon oil has more DHA than EPA while other white fishes have more EPA than DHA. One producer, Trident Food's Pure Alaska, for example reports per serving DHA 220 mg and EPA 180 mg for their salmon oil (total omega-3 = 600 mg), but DHA 144 mg and EPA 356 mg for pollock fish oil (total omega-3 = 530 mg). Equivalent products from another producer, Fish Oils, Puritan's Pride, reports DHA 180 mg and EPA 150 mg for their salmon oil product (total omega-3 = 420 mg), but DHA 204 mg and EPA 318 mg for fish oil derived from anchovy, sardine, and mackerel (total omega-3 = 600 mg). For information and comparison purposes only, no endorsements are implied.
  3. ^ Many plant sources of omega-3s are rich in ALA but completely lack EPA and DHA. The exception is algae derived oils. Because there are more commercially-grown algae sources of DHA than EPA, algae omega-3 supplements typically contain more DHA than EPA. For example, Nordic Naturals reports per serving DHA 390 mg and EPA 195 mg (total omega-3 = 715 mg), Calgee reports DHA 300 mg and EPA 150 mg (total omega-3 = 550 mg) and so on, but iwi reports EPA 250 mg (total omega-3 = 254 mg). For information and comparison purposes only, no endorsements are implied.

References

  1. PMID 21562563
    .
  2. ^ Zimmer C (September 17, 2015). "Inuit Study Adds Twist to Omega-3 Fatty Acids' Health Story". The New York Times. Archived from the original on January 9, 2019. Retrieved October 11, 2015.
  3. ^ O'Connor A (March 30, 2015). "Fish Oil Claims Not Supported by Research". The New York Times. Archived from the original on May 28, 2018. Retrieved October 11, 2015.
  4. PMID 24352849. Archived
    from the original on 2016-06-08. Retrieved 2015-10-12.
  5. PMID 30415628
    .
  6. ^ "Vascepa® (icosapent ethyl) 26% Reduction in Key Secondary Composite Endpoint of Cardiovascular Death, Heart Attacks and Stroke Demonstrated in REDUCE-IT™". November 10, 2018. Archived from the original on May 23, 2019. Retrieved January 21, 2019.
  7. ISBN 978-0-309-16338-5
    .
  8. ^ Bishop-Weston Y. "Plant based sources of vegan & vegetarian Docosahexaenoic acid – DHA and Eicosapentaenoic acid EPA & Essential Fats". Archived from the original on 2013-05-22. Retrieved 2008-08-05.
  9. PMID 25567511
    .
  10. S2CID 46917269
    .
  11. S2CID 18430041
    .
  12. ^ Halliday J (12 January 2007). "Water 4 to introduce algae DHA/EPA as food ingredient". Archived from the original on 2007-01-16. Retrieved 2007-02-09.
  13. doi:10.1046/j.1440-6047.11.s.6.5.x. Archived from the original
    (PDF) on 2008-12-17.
  14. PMID 24308505
    .
  15. doi:10.1016/s0262-4079(14)60016-6. Archived
    from the original on 1 June 2015. Retrieved 26 August 2017.
  16. PMID 23855409
    .
  17. PMID 31665653
    .
  18. ^
    PMID 12538082
    .
  19. PMID 24152561
    .
  20. S2CID 13680225
    .
  21. ^ NIH Medline Plus. "MedlinePlus Herbs and Supplements: Omega-3 fatty acids, fish oil, alpha-linolenic acid". Archived from the original on February 8, 2006. Retrieved February 14, 2006.
  22. S2CID 8793334
    .
  23. S2CID 212730542
    .
  24. PMID 27733252
    .
  25. S2CID 229325648
    .
  26. PMID 19333748
    .
  27. PMID 25798215
    .
  28. PMID 17194275. Archived
    from the original on 2020-09-20. Retrieved 2022-10-13.
  29. ^ Ilardi, Stephen (28 April 2015). "Therapeutic Lifestyle Change. A new treatment for depression". Therapeutic Lifestyle Change (TLC). Archived from the original on 9 November 2019. Retrieved 9 November 2019. We were never designed for the sedentary, indoor, sleep-deprived, socially-isolated, fast-food-laden, frenetic pace of modern life.
  30. PMID 26699442
    .

External links
Retrieved from "https://en.wikipedia.org/w/index.php?title=Eicosapentaenoic_acid&oldid=1215891959"