Intracellular and Plasma Membrane Events in Cholesterol Transport and Homeostasis
Table 1
Genes that participate in the intracellular cholesterol traffic and cholesterol homeostasis and affect the efflux of cholesterol to extracellular acceptors. Stimulation of cholesterol efflux: observed as inhibition for knockdown/knockout or stimulation for overexpression; inhibition of cholesterol efflux: observed as stimulation for knockdown/knockout or inhibition for overexpression.
Gene
Description
Cell
Acceptor
Reference
Stimulation of cholesterol efflux
ABCA1 (ATP-binding cassette transporter A1)
Mediates cholesterol efflux
MPM, THP-1, Huh7.5 (hepatoma cells), human foreskin fibroblasts
A small (18 kDa) integral membrane mitochondrial trafficking protein; participates in cholesterol transport, interacts with StAR; promotes expression of ABCA1
An endoplasmic reticulum protein that binds 25-hydroxycholesterol and other lipid molecules and transfer them between ER and PM; inhibits ABCA1 expression
A member of the pentraxin family together with short pentraxins, such as C-reactive protein and serum amyloid P component; releases in response to inflammation; inhibits ABCA1 expression
TNFRSF25 (TNF receptor superfamily member 25 aka Death receptor 3)
A cell surface receptor of TNF-like protein 1A (TL1A); highly expressed in foam cells in atherosclerotic plaques; TL1A inhibits expression of ABCA1 and ABCG1
some cases, cells were treated to differentiate to macrophages (e.g., by PMA (phorbol 12-myristate 13-acetate) or colony-stimulating factor GM-CSF), to induce expression of ABCA1 (e.g., by cpt-cAMP, TO-901317, or 22-OH+9cRA), and transformed to foam cells (e.g., by acLDL). that the gene has both stimulating and inhibiting effect depending on the type of cells and/or cholesterol acceptor. hPBMC: human peripheral blood mononuclear cells; HUVEC: human umbilical vein endothelial cells; mBMDM: mouse bone-marrow-derived macrophage; MPM: mouse peritoneal macrophage; Mβ-CD: methyl β cyclodextrin.