Deletion of lysophosphatidylcholine acyltransferase 3 in myeloid cells worsens hepatic steatosis after a high-fat diet.
Fiche publication
Date publication
décembre 2020
Journal
Journal of lipid research
Auteurs
Membres identifiés du Cancéropôle Est :
Dr LAGROST Laurent, Dr PAIS DE BARROS Jean-Paul, Pr MASSON David
Tous les auteurs :
Bourgeois T, Jalil A, Thomas C, Magnani C, Le Guern N, Gautier T, Pais de Barros JP, Bergas V, Choubley H, Mazzeo L, Menegaut L, Josiane Lebrun L, Van Dongen K, Xolin M, Jourdan T, Buch C, Labbé J, Saas P, Lagrost L, Masson D, Grober J
Lien Pubmed
Résumé
Recent studies have highlighted an important role for lysophosphatidylcholine acyltransferase 3 (LPCAT3) in controlling the PUFA composition of cell membranes in the liver and intestine. In these organs, LPCAT3 critically supports cell-membrane-associated processes such as lipid absorption or lipoprotein secretion. However, the role of LPCAT3 in macrophages remains controversial. Here, we investigated LPCAT3's role in macrophages both in vitro and in vivo in mice with atherosclerosis and obesity. To accomplish this, we used the LysMCre strategy to develop a mouse model with conditional Lpcat3 deficiency in myeloid cells (Lpcat3KO). We observed that partial Lpcat3 deficiency (approximately 75% reduction) in macrophages alters the PUFA composition of all phospholipid (PL) subclasses, including phosphatidylinositols and phosphatidylserines. A reduced incorporation of C20 PUFAs (mainly arachidonic acid [AA]) into PLs was associated with a redistribution of these FAs toward other cellular lipids such as cholesteryl esters. Lpcat3 deficiency had no obvious impact on macrophage inflammatory response or endoplasmic reticulum (ER) stress; however, Lpcat3KO macrophages exhibited a reduction in cholesterol efflux in vitro. In vivo, myeloid Lpcat3 deficiency did not affect atherosclerosis development in LDL receptor deficient mouse (Ldlr) mice. Lpcat3KO mice on a high-fat diet displayed a mild increase in hepatic steatosis associated with alterations in several liver metabolic pathways and in liver eicosanoid composition. We conclude that alterations in AA metabolism along with myeloid Lpcat3 deficiency may secondarily affect AA homeostasis in the whole liver, leading to metabolic disorders and triglyceride accumulation.
Mots clés
arachidonic acid, atherosclerosis, inflammation, insulin resistance, lipid metabolism, lysophosphatidylcholine acyltransferase 3 (LPCAT3), macrophages, obesity, phospholipid, steatosis
Référence
J Lipid Res. 2020 Dec 17;62:100013