Phospholipid fatty acid composition of various mouse tissues after feeding alpha-linolenate (18:3n-3) or eicosatrienoate (20:3n-3).
The selective incorporation of dietary alpha-linolenate (18:3n-3) and its elongation product, eicosatrienoate (20:3n-3), into various phospholipids (PL) of mouse liver, spleen, kidney, and heart, was examined in a two-week feeding trial by assessing mol % changes in associated fatty acids. Mice were fed fat-free AIN 76A diets modified with either 2 wt% safflower oil (control); 1% safflower and 1% linolenate; or 1% safflower and 1% eicosatrienoate. After linolenate or eicosatrienoate feeding, 20:4n-6 was reduced by 36-50% in liver phosphatidylcholine (PC) and in liver and spleen phosphatidylethanolamine (PE). Linolenate was minimally incorporated into PL, but was desaturated and elongated to 20:5n-3, 22:5n-3, and 22:6n-3, with notable differences in the quantity of these n-3 derivatives associated with different tissues and PL. Eicosatrienoate was uniquely incorporated into the cardiolipin (CL) pool of all organs. There was also considerable retroconversion of 20:3n-3 to 18:3n-3 (PC,PE). Dietary eicosatrienoate may therefore affect metabolism in diverse ways--20:3n-3, which is retroconverted to 18:3n-3, may provide substrate for 20:5n-3 and 22:6n-3 syntheses, whereas intact 20:3n-3 may be incorporated into the CL pool. Acyl modifications of CL are known to affect the activity of key innermitochondrial enzymes, such as cytochrome c oxidase.
Berger
A
A
Department of Food Science, University of California, Davis 95616.
German
J B
JB
D015126:8,11,14-Eicosatrienoic Acid / Q000008:administration & dosage / Q000378:metabolism*; D000818:Animals; D002308:Cardiolipins / Q000378:metabolism; D004041:Dietary Fats / Q000378:metabolism*; D005227:Fatty Acids / Q000378:metabolism*; D005260:Female; D007668:Kidney / Q000378:metabolism; D008042:Linolenic Acids / Q000008:administration & dosage / Q000378:metabolism*; D008099:Liver / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D009206:Myocardium / Q000378:metabolism; D010713:Phosphatidylcholines / Q000378:metabolism; D010714:Phosphatidylethanolamines / Q000378:metabolism; D010743:Phospholipids / Q000378:metabolism*; D013154:Spleen / Q000378:metabolism; D017962:alpha-Linolenic Acid
D002308:Cardiolipins; D004041:Dietary Fats; D005227:Fatty Acids; D008042:Linolenic Acids; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D010743:Phospholipids; D017962:alpha-Linolenic Acid; D015126:8,11,14-Eicosatrienoic Acid