Article
Details
Citation
Ghioni C, Porter AEA, Sadler IH, Tocher DR & Sargent JR (2001) Cultured fish cells metabolize octadecapentaenoic acid (all-cis delta3,6,9,12,15¨C18¡Ã5) to octadecatetraenoic acid (all-cis delta6,9,12,15¨C18¡Ã4) via its 2-trans intermediate (trans delta2, all-cis delta6,9,12,15¨C18¡Ã5). Lipids, 36 (2), pp. 145-153. http://www.springerlink.com/content/0024-4201/; https://doi.org/10.1007/s11745-001-0701-0
Abstract
Octadecapentaenoic acid (all-cis ¦¤3,6,9,12,15-18:5; 18:5n-3) is an unusual fatty acid found in marine dinophytes, haptophytes and prasinophytes. It is not present at higher trophic levels in the marine food web but its metabolism by animals ingesting algae is unknown. Here we studied the metabolism of 18:5n-3 in cell lines derived from turbot (Scophthalmus maximus), gilthead sea bream (Sparus aurata) and Atlantic salmon (Salmo salar). Cells were incubated in the presence of approximately 1 ¦ÌM [U-14C] 18:5n-3 methyl ester or [U-14C] 18:4n-3 (octadecatetraenoic acid; all-cis ¦¤6,9,12,15-18:4) methyl ester, both derived from the alga Isochrysis galbana grown in H14CO3, and also with 25 ¦ÌM unlabelled 18:5n-3 or 18:4n-3. Cells were also incubated with 25 ¦ÌM trans ¦¤2, all-cis ¦¤6,9,12,15-18:5 (2-trans 18:5n-3) produced by alkaline isomerization of 18:5n-3 chemically synthesized from docosahexaenoic acid (all-cis ¦¤4,7,10,13,16,19-22:6; 22:6n-3). Radio- and mass analyses of total fatty acids extracted from cells incubated with 18:5n-3 were consistent with this fatty acid being rapidly metabolized to 18:4n-3 which was then elongated and further desaturated to eicosatetraenoic acid (all-cis ¦¤8,11,14,17,19-20:4; 20:4n-3) and eicosapentaenoic acid (all-cis ¦¤5,8,11,14,17-20:5; 20:5n-3). Similar mass increases of 18:4n-3 and its elongation and further desaturation products occurred in cells incubated with 18:5n-3 or 2-trans 18:5n-3. We conclude that 18:5n-3 is readily converted biochemically to 18:4n-3 via a 2-trans 18:5n-3 intermediate generated by a ¦¤3,¦¤2-enoyl-CoA-isomerase acting on 18:5n-3. Thus, 2-trans 18:5n-3 is implicated as a common intermediate in the ¦Â-oxidation of both 18:5n-3 and 18:4n-3.
Keywords
Cell culture; Fish; AS cell line; TF cell line; SAF-1 cell line; Polyunsaturated fatty acids; Metabolism; Oxidation; 18:5n-3; 18:4n-3; Stearidonic acid; Intermediates; Fishes Nutrition Requirements; Fishes Feeding and feeds
Journal
Lipids: Volume 36, Issue 2
| Status | Published |
|---|---|
| Publication date | 28/02/2001 |
| URL | |
| Publisher | Springer / American Oil Chemists' Society (AOCS) |
| Publisher URL | |
| ISSN | 0024-4201 |
| eISSN | 1558-9307 |