Lipid and fatty acid composition of canine lipoproteins

Lipid classes and their fatty acids were studied in the major lipoprotein f ractions from canine, in comparison with human, plasma. In dogs, high-densi ty-lipoprotein (HDL), the main carrier of plasma phospholipid (PL), cholest erol ester (CE) and free cholesterol, was the most abundant lipoprotein, fo llowed by low and Very-low density lipoproteins (LDL and VLDL). Notably, LD L and VLDL contributed similarly to the total dog plasma triacylglycerol (T G). The PL composition was similar in ah three lipoproteins, dominated by p hosphatidylcholine (PC). Even though the content and composition of lipids within and among lipoproteins differed markedly between dog and man, the to tal amount of circulating lipid was similar. All canine lipoproteins were r elatively richer than those from humans in long-chain (C20-C22) n-6 and n-3 polyunsaturated fatty acids (PUFA) but had comparable proportions of total saturated and monoenoic fatty acids, with 18:2n-6 being the main PUFA in b oth mammals. The fatty acid profile of canine and human lipoproteins differ ed because they had distinct proportions of their major lipids. There were more n-3 and n-6 long-chain PUFA in canine than in human plasma, because do gs had more HDL, their HDL had more PC and CE, and both these lipids were r icher in such PUFA. (C) 2001 Elsevier Science Inc. All rights reserved.