Lipolysis of polyenoic fatty acid esters of human chylomicrons by lipoprotein lipase.
Human chylomicrons, obtained from chylous pleural fluid of a patient with mesothelioma, were incubated with bovine milk lipoprotein lipase. No difference in the release of different C16-C18 fatty acids as unesterified fatty acids, or in their appearance in diacylglycerols, was observed. The rate of lipolysis of arachidonic (20:4), and eicosapentaenoic (20:5) acid ester bonds of chylomicron triacylglycerols was slower, and a larger proportion of these fatty acids accumulated in mono- and diacylglycerols. The hydrolysis pattern for docosahexaenoic acid (22:6) was intermediary between that of the C16-C18 fatty acids and that of 20:4 and 20:5. The data suggest that the presence of a double bond at position 5 in the eicosanoid precursors may be important for the rate of lipolysis. The relative resistance of the 20:4- and 20:5- esters of chylomicrons to lipoprotein lipase may be important for the tissue distribution of these fatty acids.
Ekström
B
B
Department of Clinical Chemistry, University of Lund, Sweden.
Nilsson
A
A
Akesson
B
B
D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism; D002914:Chylomicrons / Q000378:metabolism*; D004281:Docosahexaenoic Acids / Q000378:metabolism; D015118:Eicosapentaenoic Acid / Q000378:metabolism; D006801:Humans; D066298:In Vitro Techniques; D008066:Lipolysis; D008071:Lipoprotein Lipase / Q000378:metabolism*; D008099:Liver / Q000378:metabolism; D014280:Triglycerides / Q000378:metabolism
D001095:Arachidonic Acids; D002914:Chylomicrons; D014280:Triglycerides; D004281:Docosahexaenoic Acids; D016718:Arachidonic Acid; D015118:Eicosapentaenoic Acid; D008071:Lipoprotein Lipase