title: Enhanced incorporation of dietary DHA into lymph phospholipids by altering its molecular carrier.
abstract: Several previous studies indicated that for optimal uptake by the brain, docosahexaenoic acid (DHA) should be present as phospholipid in the plasma. However most of dietary DHA is absorbed as triacylglycerol (TAG) because it is released as free fatty acid during digestion of either TAG-DHA (fish oil) or sn-2-DHA phospholipid (krill oil), and subsequently incorporated into TAG of chylomicrons. We tested the hypothesis that the absorption of DHA as phospholipid can be increased if it is present in the sn-1 position of dietary phospholipid or in lysophosphatidylcholine (LPC), because it would escape the hydrolysis by pancreatic phospholipase A2. We infused micelle containing the DHA either as LPC or as free acid, into the duodenum of lymph cannulated rats, and analyzed the chylomicrons and HDL of the lymph for the DHA-containing lipids. The results show that while the total amount of DHA absorbed was comparable from the two types of micelle, the percentage of DHA recovered in lymph phospholipids was 5 times greater with LPC-DHA, compared to free DHA. Furthermore, the amount of DHA recovered in lymph HDL was increased by 2-fold when LPC-DHA micelle was infused. These results could potentially lead to a novel strategy to increase brain DHA levels through the diet.
authors.affiliation: Department of Medicine, University of Illinois at Chicago, Chicago, IL 60612, United States; Department of Biochemistry & Molecular Genetics, University of Illinois at Chicago, Chicago, IL 60612, United States; Jesse Brown VA Medical Center, Chicago, IL 60612, United States. Electronic address: psubbaia@uic.edu.
authors.forename: Papasani V
authors.initials: PV
authors.lastname: Subbaiah
authors.affiliation: Department of Medicine, University of Illinois at Chicago, Chicago, IL 60612, United States.
authors.forename: Karigowda J
authors.initials: KJ
authors.lastname: Dammanahalli
authors.affiliation: Department of Medicine, University of Illinois at Chicago, Chicago, IL 60612, United States.
authors.forename: Peng
authors.initials: P
authors.lastname: Yang
authors.affiliation: Department of Physiology & Biophysics, University of Illinois at Chicago, Chicago, IL 60612, United States.
authors.forename: Jian
authors.initials: J
authors.lastname: Bi
authors.affiliation: Department of Physiology & Biophysics, University of Illinois at Chicago, Chicago, IL 60612, United States.
authors.forename: J Michael
authors.initials: JM
authors.lastname: O'Donnell
mesh_terms: D000818:Animals; D002914:Chylomicrons / Q000378:metabolism*; D004041:Dietary Fats / Q000378:metabolism / Q000494:pharmacology; D004281:Docosahexaenoic Acids / Q000378:metabolism / Q000494:pharmacology; D004386:Duodenum / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008196:Lymph / Q000378:metabolism*; D008244:Lysophosphatidylcholines / Q000378:metabolism*; D008297:Male; D054467:Phospholipases A2 / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D002914:Chylomicrons; D004041:Dietary Fats; D008244:Lysophosphatidylcholines; D004281:Docosahexaenoic Acids; D054467:Phospholipases A2
keywords: Chylomicrons/HDL; Fish oil/DHA; Lymph; Lysophosphatidylcholine; Micelles; Phospholipids/absorption