Effects of dietary purified eicosapentaenoic acid (20:5 (n-3)) and docosahexaenoic acid (22:6(n-3)) on fatty acid desaturation and oxidation in isolated rat liver cells.
The effects of dietary supplementation of eicosapentaenoic acid (20:5(n-3), EPA) and docosahexaenoic acid (22:6(n-3), DHA) on the metabolism of polyunsaturated fatty acids were studied in isolated rat liver cells. Both pure EPA and pure DHA and a mixture of the two n-3 fatty acids in different doses were used. The supplementation of moderate amounts of n-3 fatty acids suppressed the activity of delta 6-desaturase (50%) and to a smaller extent of the delta 5-desaturase (60-70%) compared to controls. When higher doses of dietary purified EPA and DHA were used, this inhibitory effect on the delta 6- and delta 5-desaturase activities disappeared. The delta 4-desaturase activity seemed to be unaffected by the feeding conditions used. The supplementation of the n-3 fatty acids in the diet at all dose levels used increased the beta-oxidation of all the polyunsaturated fatty acids, especially of linoleic acid, linolenic acid and eicosapentaenoic acid. The results suggest an increase both in peroxisomal and mitochondrial beta-oxidation. The peroxisomal beta-oxidation of n-3 fatty acids seemed to be particularly increased.
Grønn
M
M
Institute of Clinical Biochemistry, University of Oslo, Norway.
Christensen
E
E
Hagve
T A
TA
Christophersen
B O
BO
D000818:Animals; D002478:Cells, Cultured; D004041:Dietary Fats / Q000494:pharmacology*; D004281:Docosahexaenoic Acids / Q000494:pharmacology*; D015118:Eicosapentaenoic Acid / Q000302:isolation & purification / Q000494:pharmacology*; D004951:Esterification; D005227:Fatty Acids / Q000378:metabolism*; D008099:Liver / Q000166:cytology / Q000378:metabolism*; D008297:Male; D010084:Oxidation-Reduction; D010743:Phospholipids / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D014280:Triglycerides / Q000378:metabolism
D004041:Dietary Fats; D005227:Fatty Acids; D010743:Phospholipids; D014280:Triglycerides; D004281:Docosahexaenoic Acids; D015118:Eicosapentaenoic Acid