Dihomo-γ-linolenic acid
Dihomo-γ-linolenic acid (DGLA) is a 20-carbon ω−6 fatty acid. (also called, cis,cis,cis-8,11,14-Eicosatrienoic acid) In physiological literature, it is given the name 20:3 (ω−6). DGLA is a carboxylic acid with a 20-carbon chain and three cis double bonds; the first double bond is located at the sixth carbon from the omega end. DGLA is the elongation product of γ-linolenic acid (GLA; 18:3, ω−6). GLA, in turn, is a desaturation product (Delta 6 desaturase) of linoleic acid (18:2, ω−6). DGLA is made in the body by the elongation of GLA, by an efficient enzyme which does not appear to suffer any form of (dietary) inhibition. DGLA is an extremely uncommon fatty acid, found only in trace amounts in animal products.[1][2]
Names | |
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Preferred IUPAC name
(8E,11E,14E)-Icosa-8,11,14-trienoic acid | |
Other names
cis,cis,cis-8,11,14-Eicosatrienoic acid; DGLA; Diroleuton (INNTooltip International Nonproprietary Name) | |
Identifiers | |
3D model (JSmol) |
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ChemSpider | |
ECHA InfoCard | 100.015.667 |
PubChem CID |
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UNII | |
CompTox Dashboard (EPA) |
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Properties | |
C20H34O2 | |
Molar mass | 306.490 g·mol−1 |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references |
Biological effects
The eicosanoid metabolites of DGLA are:
- Series-1 thromboxanes (thromboxanes with 1 double-bond), via the COX-1 and COX-2 pathways.
- Series-1 prostanoids, via the COX-1 and COX-2 pathways.[3]
- A 15-hydroxyl derivative that blocks the transformation of arachidonic acid to leukotrienes.[4]
All of these effects are anti-inflammatory. This is in marked contrast with the analogous metabolites of arachidonic acid (AA), which are the series-2 thromboxanes and prostanoids and the series-4 leukotrienes. In addition to yielding anti-inflammatory eicosanoids, DGLA competes with AA for COX and lipoxygenase, inhibiting the production of AA's eicosanoids.
Taken orally in a small study, DGLA produced antithrombotic effects.[5] Supplementing dietary GLA increases serum DGLA, as well as serum AA levels.[6] Cosupplementation with GLA and EPA lowers serum AA levels by blocking Δ-5-desaturase activity, while also lowering leukotriene synthesis in neutrophils.[7]
See also
References
- Horrobin, D. F., 1990a. Gamma linolenic acid. Rev. Contemp. Pharmacother. 1, 1-45
- Huang, Y.-S. and Mills, D. E. (Eds.), 1996. Gamma-linolenic acid metabolism and its roles in nutrition and medicine. AOCS Press, Champaign, Illinois, 319 pp.
- Fan, Yang-Yi; Robert S. Chapkin (9 September 1998). "Importance of Dietary γ-Linolenic Acid in Human Health and Nutrition". Journal of Nutrition. 128 (9): 1411–4. doi:10.1093/jn/128.9.1411. PMID 9732298. Retrieved 2007-10-16.
- Belch, Jill JF; Alexander Hill (January 2000). "Evening primrose oil and borage oil in rheumatologic conditions". The American Journal of Clinical Nutrition. 71 (1 Suppl): 352S–6S. doi:10.1093/ajcn/71.1.352s. PMID 10617996. Retrieved February 12, 2006.
- Kernoff PB, Willis AL, Stone KJ, Davies JA, McNicol GP (1977). "Antithrombotic potential of dihomo-γ-linolenic acid in man". British Medical Journal. 2 (6100): 1441–1444. doi:10.1136/bmj.2.6100.1441. PMC 1632618. PMID 338112.
- Johnson MM, Swan DD, Surette ME, et al. (1997). "Dietary supplementation with γ-linolenic acid alters fatty acid content and eicosanoid production in healthy humans". J. Nutr. 127 (8): 1435–44. doi:10.1093/jn/127.8.1435. PMID 9237935.
- Barham JB, Edens MB, Fonteh AN, Johnson MM, Easter L, Chilton FH (August 2000). "Addition of eicosapentaenoic acid to gamma-linolenic acid-supplemented diets prevents serum arachidonic acid accumulation in humans". J. Nutr. 130 (8): 1925–31. doi:10.1093/jn/130.8.1925. PMID 10917903.