title: Echium oil reduces plasma triglycerides by increasing intravascular lipolysis in apoB100-only low density lipoprotein (LDL) receptor knockout mice.
abstract: Echium oil (EO), which is enriched in SDA (18:4 n-3), reduces plasma triglyceride (TG) concentrations in humans and mice. We compared mechanisms by which EO and fish oil (FO) reduce plasma TG concentrations in mildly hypertriglyceridemic male apoB100-only LDLrKO mice. Mice were fed one of three atherogenic diets containing 0.2% cholesterol and palm oil (PO; 20%), EO (10% EO + 10% PO), or FO (10% FO + 10% PO). Livers from PO- and EO-fed mice had similar TG and cholesteryl ester (CE) content, which was significantly higher than in FO-fed mice. Plasma TG secretion was reduced in FO vs. EO-fed mice. Plasma very low density lipoprotein (VLDL) particle size was ordered: PO (63 ± 4 nm) > EO (55 ± 3 nm) > FO (40 ± 2 nm). Post-heparin lipolytic activity was similar among groups, but TG hydrolysis by purified lipoprotein lipase was significantly greater for EO and FO VLDL compared to PO VLDL. Removal of VLDL tracer from plasma was marginally faster in EO vs. PO fed mice. Our results suggest that EO reduces plasma TG primarily through increased intravascular lipolysis of TG and VLDL clearance. Finally, EO may substitute for FO to reduce plasma TG concentrations, but not hepatic steatosis in this mouse model.
authors.affiliation: Department of Pathology/Section on Lipid Sciences, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA. lolita_forrest@med.unc.edu
authors.forename: Lolita M
authors.initials: LM
authors.lastname: Forrest
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Lough
authors.forename: Soonkyu
authors.initials: S
authors.lastname: Chung
authors.forename: Elena Y
authors.initials: EY
authors.lastname: Boudyguina
authors.forename: Abraham K
authors.initials: AK
authors.lastname: Gebre
authors.forename: Thomas L
authors.initials: TL
authors.lastname: Smith
authors.forename: Perry L
authors.initials: PL
authors.lastname: Colvin
authors.forename: John S
authors.initials: JS
authors.lastname: Parks
mesh_terms: D000818:Animals; D053299:Apolipoprotein B-100 / Q000097:blood*; D002788:Cholesterol Esters / Q000097:blood; D015243:Cholesterol, VLDL / Q000097:blood; D036661:Echium / Q000737:chemistry*; D005395:Fish Oils / Q000494:pharmacology; D015870:Gene Expression; D008066:Lipolysis / Q000187:drug effects*; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D000073878:Palm Oil; D010938:Plant Oils / Q000494:pharmacology*; D012313:RNA / Q000235:genetics / Q000302:isolation & purification; D011973:Receptors, LDL / Q000097:blood*; D014280:Triglycerides / Q000097:blood*
chemical_list: D053299:Apolipoprotein B-100; D002788:Cholesterol Esters; D015243:Cholesterol, VLDL; D005395:Fish Oils; D010938:Plant Oils; D011973:Receptors, LDL; D014280:Triglycerides; D000073878:Palm Oil; D012313:RNA