Effect of temperature on the incorporation into phospholipid classes and metabolismvia desaturation and elongation of n−3 and n−6 polyunsaturated fatty acids in fish cells in culture

• Published in: Lipids
• Main Authors: Tocher, Douglas R., Sargent, John R.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1990
• Subjects: Atlantic salmon; Turbot
• Online Access: http://dx.doi.org/10.1007/bf02538085; https://onlinelibrary.wiley.com/doi/full/10.1007/BF02538085

Abstract The incorporation of 18∶2n−6, 18∶3n−3, 20∶4n−6 and 20∶5n−3 was greater at 10°C than at 22°C in Atlantic salmon (AS), rainbow trout (RTG‐2) and turbot (TF) cells. However, there were generally no significant differences between the amount of incorporation of all four polyunsaturated fatty acids (PUFA) into total lipid within a cell type at either 22°C or 10°C. The distributions of the PUFA between individual phospholipid classes at 22°C was essentially the same in AS and TF cells—with the C 18 PUFA the order of incorporation in these cells was phosphatidylcholine (PC) > phosphatidylethanolamine (PE) > phosphatidic acid/cardiolipin (PA/CL); with 20∶4n−6 the order was PE and phosphatidylinositol (PI)>PC; with 20∶5n−3, PE>PC. In RTG‐2 cells at 22°C the distributions of the C 18 PUFA were similar to the other cell lines, but with 20∶4n−6 the order was PC>PI>PE, and with 20∶5n−3 it was PC>PE. At 10°C the incorporation of C 18 PUFA into PC increased and into PE and PA/CL decreased, in general, in all cell lines. Incorporation of 20∶5n−3 into PC and PE was increased and decreased at 10°C, respectively, in AS and TF cells, whereas in RTG‐2 cells the changes at 10°C were opposite i.e., increased in PE and decreased in PC. With 20∶4n−6, incorporation into PC at 10°C was increased in all cell lines with decreased incorporation into PI in AS and RTG‐2 cells and into PE in AS and TF cells, whereas incorporation of 20∶4n−6 into PE increased in RTG‐2 cells. The metabolism via desaturation and elongation of the n−3 PUFA was greater than that of the equivalent n−6 PUFA in all cell lines, irrespective of temperature. There was less conversion of the C 18 PUFA at 10°C than at 22°C in RTG‐2 and TF cells, but the conversion of 18∶3n−3 by AS cells was increased at 10°C. Temperature had no effect on the conversion of the C 20 PUFA.