ALDH2 deficiency inhibits Ox-LDL induced foam cell formation via suppressing CD36 expression

Biochem Biophys Res Commun. 2019 Apr 23;512(1):41-48. doi: 10.1016/j.bbrc.2019.02.012. Epub 2019 Mar 8.

Abstract

Foam cell formation plays an important role in the initiation and progression of atherosclerosis. Aldehyde dehydrogenase 2 (ALDH2), a key enzyme for aldehyde metabolism, is associated with coronary artery disease and affects atherosclerotic plaque vulnerability. However, the role of ALDH2 in foam cell formation remains unclear. Using peritoneal macrophages from ALDH2-deficient and control mice, we found that ALDH2 deficiency suppressed foam cell formation induced by oxidized low-density lipoproteins (ox-LDL) but not acetylated low-density lipoproteins (ac-LDL) ex vivo. After incubation with ox-LDL, ALDH2-deficient macrophages expressed lower levels of CD36 but the expression of other lipid metabolism-related proteins including SRA, LOX-1, ABCA-1, ABCG-1 and ACAT-1 was not changed in ALDH2-/- macrophages. Using CD36 inhibitor, we confirmed that CD36 contributes to the effect of ALDH2 on foam cell formation. PPARγ was downregulated in ox-LDL treated ALDH2-/- macrophages. 4-HNE was increased by ALDH2 deficiency and high concentration of 4-HNE suppressed the expression of PPARγ. These data suggest that ALDH2 plays an important role in foam cell formation via 4-HNE/PPARγ/CD36 pathway.

Keywords: Aldehyde dehydrogenase 2; Atherosclerosis; CD36; Foam cell; PPARγ.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aldehyde Dehydrogenase, Mitochondrial / deficiency*
  • Aldehyde Dehydrogenase, Mitochondrial / genetics
  • Aldehydes / metabolism
  • Aldehydes / pharmacology
  • Animals
  • Apoptosis / drug effects
  • Atherosclerosis / etiology
  • Atherosclerosis / metabolism
  • Atherosclerosis / pathology
  • CD36 Antigens / metabolism*
  • Down-Regulation
  • Foam Cells / drug effects
  • Foam Cells / metabolism*
  • Foam Cells / pathology
  • In Vitro Techniques
  • Lipoproteins, LDL / metabolism*
  • Lipoproteins, LDL / pharmacology
  • Macrophages, Peritoneal / drug effects
  • Macrophages, Peritoneal / metabolism
  • Macrophages, Peritoneal / pathology
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Models, Cardiovascular
  • PPAR gamma / metabolism
  • Signal Transduction

Substances

  • Aldehydes
  • CD36 Antigens
  • Cd36 protein, mouse
  • Lipoproteins, LDL
  • PPAR gamma
  • oxidized low density lipoprotein
  • ALDH2 protein, mouse
  • Aldehyde Dehydrogenase, Mitochondrial
  • 4-hydroxy-2-nonenal