title: Involvement of lipid droplets in hepatic responses to lipopolysaccharide treatment in mice.
abstract: Infection and inflammation induce important changes in lipid metabolism, which result in increased free fatty acids and triacylglycerol in plasma and altered high density lipoprotein (HDL) metabolism. Our aim was to elucidate whether hepatic lipid droplets (LDs) are involved in the adaptations of lipid metabolism to endotoxemia. We characterized the lipid content and several enzymatic activities in subcellular fractions and subpopulations of LDs from livers of mice 24h after lipopolysaccharide (LPS) treatment and analyzed the expression of key genes involved in lipid management. Endotoxemic mice showed lower lipid content in LDs with decreased molar fraction of cholesteryl ester and higher diacylglycerol/triacylglycerol ratio as compared to their controls. They also showed a decrease in cytosolic triacylglycerol hydrolase activity, specifically in dense LDs, and in microsomal and cytosolic diacylglycerol hydrolase activity; concomitantly neutral lipid biosynthetic capacity and triacylglycerol levels in plasma lipoproteins increased. Together with the overexpression of genes involved in lipogenesis and HDL formation our results suggest that altered hepatic management of LD lipids in LPS-treated mice might be related to the channeled mobilization of triacylglycerol for very low density lipoprotein assembly and to the induction of cholesterol export.
authors.affiliation: Department of Physiology, University of the Basque Country, Leioa, Spain. linoarisqueta@hotmail.com
authors.forename: Lino
authors.initials: L
authors.lastname: Arisqueta
authors.forename: Maitane
authors.initials: M
authors.lastname: Nuñez-Garcia
authors.forename: Jesus
authors.initials: J
authors.lastname: Ogando
authors.forename: Itsaso
authors.initials: I
authors.lastname: Garcia-Arcos
authors.forename: Begoña
authors.initials: B
authors.lastname: Ochoa
authors.forename: Patricia
authors.initials: P
authors.lastname: Aspichueta
authors.forename: Olatz
authors.initials: O
authors.lastname: Fresnedo
authors.forename: Yuri
authors.initials: Y
authors.lastname: Rueda
mesh_terms: D000818:Animals; D002784:Cholesterol / Q000097:blood; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects; D050356:Lipid Metabolism / Q000187:drug effects*; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008075:Lipoproteins, HDL / Q000097:blood; D008099:Liver / Q000378:metabolism*; D051379:Mice; D008862:Microsomes, Liver / Q000378:metabolism*; D014280:Triglycerides / Q000097:blood
chemical_list: D008070:Lipopolysaccharides; D008075:Lipoproteins, HDL; D014280:Triglycerides; D002784:Cholesterol