In CCR2-/- mice monocyte recruitment and egress of LDL cholesterol in vivo is impaired

Biochem Biophys Res Commun. 2003 Jan 10;300(2):477-81. doi: 10.1016/s0006-291x(02)02862-0.

Abstract

Recruitment of macrophages plays an important role in initiation of atheroma, but their involvement in cholesterol clearance during regression is unknown. We developed a mouse model to quantitate cholesterol clearance from a depot of cationized LDL injected into a leg muscle, which evokes a sterile inflammatory reaction. In the CCR2(-/-) mice, cholesterol clearance was significantly slower than in C57BL controls because of decrease in cholesteryl ester (CE) hydrolysis, which is mandatory prior to cholesterol efflux. In CCR2(-/-) mice, macrophage recruitment to the injected site, identified by immunohistochemistry, was markedly delayed. CE hydrolysis was also significantly reduced in thioglycollate elicited peritoneal exudate cells of CCR2(-/-) mice, related to paucity of macrophages in the cell differential. The present study provides definite evidence that recruitment of macrophages is required for LDL cholesterol clearance, which plays a prominent role in regression of an atheroma.

MeSH terms

  • Animals
  • Biological Transport
  • Cell Movement*
  • Cells, Cultured
  • Cholesterol / metabolism
  • Cholesterol Esters / metabolism
  • Cholesterol, LDL / metabolism*
  • Female
  • Kinetics
  • Lipids / blood
  • Macrophages / physiology*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Monocytes / physiology*
  • Muscle, Skeletal / cytology
  • Muscle, Skeletal / metabolism
  • Receptors, CCR2
  • Receptors, Chemokine / genetics
  • Receptors, Chemokine / physiology*

Substances

  • Ccr2 protein, mouse
  • Cholesterol Esters
  • Cholesterol, LDL
  • Lipids
  • Receptors, CCR2
  • Receptors, Chemokine
  • Cholesterol