title: Nicotinic acid inhibits progression of atherosclerosis in mice through its receptor GPR109A expressed by immune cells.
abstract: Nicotinic acid (niacin) is a drug used to reduce the progression of atherosclerosis. Its antiatherosclerotic activity is believed to result from lipid-modifying effects, including its ability to decrease LDL cholesterol and increase HDL cholesterol levels in plasma. Here, we report that in a mouse model of atherosclerosis, we found that nicotinic acid inhibited disease progression under conditions that left total cholesterol and HDL cholesterol plasma levels unaffected. The antiatherosclerotic effect was not seen in mice lacking the receptor for nicotinic acid GPR109A. Surprisingly, transplantation of bone marrow from GPR109A-deficient mice into atherosclerosis-prone animals also abrogated the beneficial effect of nicotinic acid. We detected expression of GPR109A in macrophages in atherosclerotic plaques. In macrophages from WT mice, but not from GPR109A-deficient animals, nicotinic acid induced expression of the cholesterol transporter ABCG1 and promoted cholesterol efflux. Furthermore, activation of GPR109A by nicotinic acid inhibited MCP-1-induced recruitment of macrophages into the peritoneal cavity and impaired macrophage recruitment to atherosclerotic plaques. In contrast with current models, our data show that nicotinic acid can reduce the progression of atherosclerosis independently of its lipid-modifying effects through the activation of GPR109A on immune cells. We conclude therefore that GPR109A mediates antiinflammatory effects, which may be useful for treating atherosclerosis and other diseases.
authors.affiliation: Department of Pharmacology, Max-Planck-Institute for Heart and Lung Research, Bad Nauheim, Germany.
authors.forename: Martina
authors.initials: M
authors.lastname: Lukasova
authors.forename: Camille
authors.initials: C
authors.lastname: Malaval
authors.forename: Andreas
authors.initials: A
authors.lastname: Gille
authors.forename: Jukka
authors.initials: J
authors.lastname: Kero
authors.forename: Stefan
authors.initials: S
authors.lastname: Offermanns
mesh_terms: D000070998:ATP Binding Cassette Transporter, Subfamily G, Member 1; D018528:ATP-Binding Cassette Transporters / Q000378:metabolism; D017667:Adipocytes / Q000166:cytology; D000818:Animals; D001011:Aorta / Q000378:metabolism; D050197:Atherosclerosis / Q000188:drug therapy*; D008076:Cholesterol, HDL / Q000378:metabolism; D022202:Chromosomes, Artificial, Bacterial / Q000378:metabolism; D018450:Disease Progression; D007107:Immune System; D008055:Lipids / Q000097:blood; D008074:Lipoproteins / Q000378:metabolism; D008264:Macrophages / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009525:Niacin / Q000378:metabolism*; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism*; D011978:Receptors, Nicotinic / Q000378:metabolism*
chemical_list: C487540:ABCG1 protein, mouse; D000070998:ATP Binding Cassette Transporter, Subfamily G, Member 1; D018528:ATP-Binding Cassette Transporters; D008076:Cholesterol, HDL; C530636:HCAR2 protein, human; D008055:Lipids; D008074:Lipoproteins; D043562:Receptors, G-Protein-Coupled; D011978:Receptors, Nicotinic; D009525:Niacin