Overexpression of human apolipoprotein A-II in transgenic mice does not impair macrophage-specific reverse cholesterol transport in vivo.
BACKGROUND
Overexpression of human apolipoprotein (apo) A-II in transgenic mice induces high-density lipoprotein (HDL) deficiency, and increased atherosclerosis susceptibility only when fed an atherogenic diet. This may, in part, be caused by impairment in reverse cholesterol transport (RCT).


RESULTS
[3H]cholesterol-labeled macrophages were injected intraperitoneally into mice maintained on a chow diet or an atherogenic diet. Plasma [3H]cholesterol did not differ from human apoA-II transgenic and control mice at 24 or 48 hours after the label injection. On the chow diet, human apoA-II transgenic mice presented increased [3H]cholesterol in liver (1.3-fold) and feces (6-fold) compared with control mice (P<0.05). The magnitude of macrophage-specific RCT did not differ between transgenic and control mice fed the atherogenic diet.


CONCLUSIONS
Human apoA-II maintains effective RCT from macrophages to feces in vivo despite an HDL deficiency. These findings suggest that the increased atherosclerotic lesions observed in apoA-II transgenic mice fed an atherogenic diet are not caused by impairment in macrophage-specific RCT.
Servei de Bioquímica, Institut de Recerca, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
Noemí
N
Rotllan
Vicent
V
Ribas
Laura
L
Calpe-Berdiel
Jesús M
JM
Martín-Campos
Francisco
F
Blanco-Vaca
Joan Carles
JC
Escolà-Gil
D000818:Animals; D016633:Apolipoprotein A-II / Q000235:genetics* / Q000378:metabolism; D050197:Atherosclerosis / Q000276:immunology* / Q000378:metabolism*; D002478:Cells, Cultured; D002784:Cholesterol / Q000493:pharmacokinetics*; D004036:Diet, Atherogenic; D005243:Feces; D015870:Gene Expression; D006801:Humans; D008075:Lipoproteins, HDL / Q000172:deficiency / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008264:Macrophages / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D014316:Tritium
D016633:Apolipoprotein A-II; D008075:Lipoproteins, HDL; D014316:Tritium; D002784:Cholesterol