title: Lysophosphatidylserine has Bilateral Effects on Macrophages in the Pathogenesis of Atherosclerosis.
abstract: OBJECTIVE
  Lysophospholipids, particularly sphingosine 1-phosphate and lysophosphatidic acid, are known to be involved in the pathogenesis of atherosclerosis; however, the role of lysophosphatidylserine (LysoPS) in the onset of atherosclerotic diseases remains uncertain.
  
  
  METHODS
  We investigated the effects of LysoPS on the uptake of oxidized low-density lipoprotein (oxLDL) and the modulation of inflammatory mediators and ER stress utilizing RAW264.7 cells and mouse peritoneal macrophages (MPMs).
  
  
  RESULTS
  We found that LysoPS augmented cholesterol accumulation in both models. Consistent with these findings, LysoPS increased the expression of scavenger receptors (CD36, MSR1, LOX1 and TLR4). Regarding the involvement of these lipids in inflammation, LysoPS significantly decreased the expression of inflammatory mediators in lipopolysaccharide (LPS)-treated RAW264.7 cells and MPMs. LysoPS also attenuated ER stress in LPS-untreated RAW264.7 cells. The expression patterns of LysoPS receptors differed considerably among the LPS-untreated RAW264.7 cells, LPS-treated RAW264.7 cells and MPMs.
  
  
  CONCLUSIONS
  LysoPS may have proatherosclerotic properties in the setting of foam cell formation as well as antiatherosclerotic effects on inflammation in macrophages.
authors.affiliation: Department of Clinical Laboratory Medicine, Graduate School of Medicine, University of Tokyo, Japan.
authors.forename: Masako
authors.initials: M
authors.lastname: Nishikawa
authors.forename: Makoto
authors.initials: M
authors.lastname: Kurano
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Ikeda
authors.forename: Junken
authors.initials: J
authors.lastname: Aoki
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Yatomi
mesh_terms: D000818:Animals; D050197:Atherosclerosis / Q000503:physiopathology*; D002460:Cell Line; D004721:Endoplasmic Reticulum / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology; D008077:Lipoproteins, LDL / Q000378:metabolism; D008246:Lysophospholipids / Q000502:physiology*; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D051379:Mice
chemical_list: D008070:Lipopolysaccharides; D008077:Lipoproteins, LDL; D008246:Lysophospholipids; C025059:lysophosphatidylserine; C099252:oxidized low density lipoprotein