title: Tracking fatty acid kinetics in distinct lipoprotein fractions in vivo: a novel high-throughput approach for studying dyslipidemia in rodent models.
abstract: Isotopic tracers have been used to examine lipid trafficking for many years, and data from those studies have typically yielded novel insight regarding the pathophysiology of dyslipidemia. Previous experimental designs were suitable for studies in humans because relatively large volumes of plasma could be regularly sampled. We have expanded on the earlier logic by applying high-throughput analytical methods that require reduced sample volumes. Specifically, we have examined the possibility of coupling gel-based separations of lipoproteins (e.g., lipoprint) with LC-MS/MS analyses of complex lipid mixtures as a way to routinely measure the labeling profiles of distinct lipids in discrete lipoprotein subfractions. We demonstrate the ability to measure the incorporation of [U-(13)C]oleate into triglycerides (TG), PLs (PL), and cholesterol esters (CE) in VLDL, LDL, and HDL particles in mice. Although rodent models of dyslipidemia are inherently different from humans because of alterations in enzyme activities and underlying metabolism, rodent models can be used to screen novel compounds for efficacy in altering a given biochemical pathway and therein enable studies of target engagement in vivo. We expect that it is possible to translate our approach for application in other systems, including studies in humans.
authors.affiliation: Merck Research Laboratories, Rahway, NJ 07065, USA.
authors.forename: David G
authors.initials: DG
authors.lastname: McLaren
authors.forename: Sheng-Ping
authors.initials: SP
authors.lastname: Wang
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Stout
authors.forename: Dan
authors.initials: D
authors.lastname: Xie
authors.forename: Paul L
authors.initials: PL
authors.lastname: Miller
authors.forename: Vivienne
authors.initials: V
authors.lastname: Mendoza
authors.forename: Raymond
authors.initials: R
authors.lastname: Rosa
authors.forename: Jose
authors.initials: J
authors.lastname: Castro-Perez
authors.forename: Stephen F
authors.initials: SF
authors.lastname: Previs
authors.forename: Douglas G
authors.initials: DG
authors.lastname: Johns
authors.forename: Thomas P
authors.initials: TP
authors.lastname: Roddy
mesh_terms: D000818:Animals; D001692:Biological Transport; D005591:Chemical Fractionation / Q000379:methods*; D004195:Disease Models, Animal; D050171:Dyslipidemias / Q000378:metabolism*; D005227:Fatty Acids / Q000378:metabolism*; D006801:Humans; D007553:Isotope Labeling; D008074:Lipoproteins / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL
chemical_list: D005227:Fatty Acids; D008074:Lipoproteins