title: Effects of human pancreatic lipase-colipase and carboxyl ester lipase on eicosapentaenoic and arachidonic acid ester bonds of triacylglycerols rich in fish oil fatty acids.
abstract: Fish oil chylomicrons, obtained from mesenteric duct chyle of rats fed [3H]20:5 and [14C]20:4 or [3H]20:5 and [14C]18:2 in a fish oil emulsion, were incubated with human pancreatic lipase-colipase, human carboxyl ester lipase (CEL) and human duodenal contents. With duodenal contents, the triacylglycerols labelled with [3H]20:5 and [14C]20:4 were rapidly converted to free fatty acids (FFA) and monoacylglycerols. Also during incubation with lipase-colipase the [3H]- and [14C]triacylglycerols disappeared completely and at equal rates, but in this case much [3H]20:5 and [14C]20:4 accumulated in diacylglycerols. When CEL was also added, the rate of disappearance of [3H]- and [14C]triacylglycerols increased and the radioactivity of diacylglycerols decreased markedly. During incubation of chylomicrons labelled with [3H]20:5 and [14C]18:2 with lipase-colipase, the rates of hydrolysis of [3H]- and [14C]triacylglycerols were similar, but more [3H]20:5 than [14C]18:2 accumulated in diacylglycerols. The accumulation of [3H]diacylglycerol was reduced by adding CEL. Also when fatty acids were analyzed by gas chromatography, 20:5 was enriched in remaining triacylglycerol and in diacylglycerol after incubation with lipase-colipase alone. The data thus indicate that both lipase-colipase and CEL participate in the hydrolysis of 20:5 and 20:4 ester bonds of dietary triacylglycerol.
authors.affiliation: Department of Medicine, University of Lund, Sweden.
authors.forename: Q
authors.initials: Q
authors.lastname: Chen
authors.forename: B
authors.initials: B
authors.lastname: Sternby
authors.forename: B
authors.initials: B
authors.lastname: Akesson
authors.forename: A
authors.initials: A
authors.lastname: Nilsson
mesh_terms: D000818:Animals; D001095:Arachidonic Acids / Q000378:metabolism*; D002250:Carbon Radioisotopes; D002265:Carboxylic Ester Hydrolases / Q000494:pharmacology*; D002914:Chylomicrons; D003089:Colipases / Q000494:pharmacology*; D004386:Duodenum / Q000187:drug effects / Q000378:metabolism*; D005395:Fish Oils / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D008049:Lipase / Q000494:pharmacology; D008297:Male; D011506:Proteins / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D014280:Triglycerides / Q000378:metabolism*
chemical_list: D001095:Arachidonic Acids; D002250:Carbon Radioisotopes; D002914:Chylomicrons; D003089:Colipases; D005395:Fish Oils; D011506:Proteins; D014280:Triglycerides; D002265:Carboxylic Ester Hydrolases; D008049:Lipase