The molecular structure of apolipoprotein A-II modulates the capacity of HDL to promote cell cholesterol efflux.
The influence of apolipoprotein A-II (apoA-II) molecular structure on the capacity of high density lipoproteins (HDL) to promote cellular cholesterol efflux was investigated in cultured mouse peritoneal macrophages (MPM). Conversion by reduction and carboxamidomethylation of the naturally occurring dimeric apoA-II to its monomeric form in both native or reconstituted HDL did not change apolipoprotein secondary structure and lipoprotein size/composition. All particles containing monomeric apoA-II, i.e., native HDL3 or reconstituted HDL with or without apoA-I, showed a higher ability to promote cholesterol efflux originating from plasma membrane and intracellular stores, compared to particles containing dimeric apoA-II. These findings indicate that apolipoprotein molecular structure is a major determinant of HDL capacity to promote cholesterol efflux from cells.
Bernini
F
F
Institute of Pharmacology and Pharmacognosy, University of Parma, Italy.
Calabresi
L
L
Bonfadini
G
G
Franceschini
G
G
D000818:Animals; D016633:Apolipoprotein A-II / Q000737:chemistry / Q000378:metabolism*; D001161:Arteriosclerosis / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D002784:Cholesterol / Q000378:metabolism*; D008075:Lipoproteins, HDL / Q000737:chemistry / Q000378:metabolism*; D017737:Macrophages, Peritoneal / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D015394:Molecular Structure
D016633:Apolipoprotein A-II; D008075:Lipoproteins, HDL; D002784:Cholesterol