title: Increased hepatic beta-oxidation of docosahexaenoic acid, elongation of eicosapentaenoic acid, and acylation of lysophosphatidate in rats fed a docosahexaenoic acid-enriched diet.
abstract: Rats were fed a diet supplemented with corn oil (n-3 deficient), soy oil, or a mixture containing 8% 22:6n-3 ethyl ester for 6 wk. The hepatic capacities for the beta-oxidation and synthesis of 22:6n-3, in addition to the acylation of lysophosphatidate, were tested in vitro. In rats that were fed a 22:6n-3-enriched diet, both the beta-oxidation of 22:6n-3 and elongation of 20:5n-3 were enhanced compared to those in rats fed the other diets. Acylation of lysophosphatidate was also enhanced in rats fed a 22:6n-3-enriched diet, while the rate of dephosphorylation of phosphatidate was not changed. The amount of 22:6n-3 in the liver was much less than that consumed in a docosahexaenoic acid-enriched diet. These results suggest that a significant amount of dietary 22:6n-3 was degraded via beta-oxidation, and that a portion of the retroconverted 20:5n-3 was recycled for the synthesis of 22:6n-3. The recycling of 20:5n-3 might contribute to the low level of 22:6n-3 in rats fed an n-3-deficient diet.
authors.affiliation: Department of Applied Biological Chemistry, Faculty of Agriculture, Tohoku University, Sendai, Japan. ayk@biochem.tohoku.ac.jp
authors.forename: A
authors.initials: A
authors.lastname: Kanazawa
authors.forename: Y
authors.initials: Y
authors.lastname: Shirota
authors.forename: K
authors.initials: K
authors.lastname: Fujimoto
mesh_terms: D000215:Acylation; D000818:Animals; D001835:Body Weight; D002851:Chromatography, High Pressure Liquid; D003314:Corn Oil / Q000378:metabolism; D004042:Dietary Fats, Unsaturated / Q000378:metabolism*; D004281:Docosahexaenoic Acids / Q000378:metabolism* / Q000494:pharmacology*; D015118:Eicosapentaenoic Acid / Q000378:metabolism*; D005227:Fatty Acids / Q000032:analysis; D066298:In Vitro Techniques; D008055:Lipids / Q000172:deficiency; D008099:Liver / Q000378:metabolism*; D008246:Lysophospholipids / Q000378:metabolism*; D008297:Male; D009929:Organ Size; D010084:Oxidation-Reduction; D051381:Rats; D017207:Rats, Sprague-Dawley; D013024:Soybean Oil / Q000378:metabolism; D014280:Triglycerides / Q000737:chemistry
chemical_list: D004042:Dietary Fats, Unsaturated; D005227:Fatty Acids; D008055:Lipids; D008246:Lysophospholipids; D014280:Triglycerides; D004281:Docosahexaenoic Acids; D013024:Soybean Oil; D003314:Corn Oil; D015118:Eicosapentaenoic Acid