Monocyte/macrophage expression of ABCA1 has minimal contribution to plasma HDL levels.
J Clin Invest
; 108(9): 1315-20, 2001 Nov.
Article
en En
| MEDLINE
| ID: mdl-11696576
Excess accumulation of cholesterol in macrophages results in foam cell production and lesion development. Recent studies have demonstrated that ATP-binding cassette protein A1 (ABCA1) is highly regulated in macrophages and mediates the efflux of cholesterol and phospholipids to apolipoproteins, a process necessary for HDL formation. The goal of this study was to determine the contribution of monocyte/macrophage ABCA1 to HDL formation in vivo. We generated mice expressing ABCA1 in macrophages and mice with selected inactivation of ABCA1 in macrophages by bone marrow transplantation in ABCA1-deficient (ABC1(-/-)) and wild-type (WT) mice. At all times, the level of HDL in ABC1(-/-) recipient mice remained low relative to WT recipient mice irrespective of the genotype of the donor macrophage ABCA1 or high-fat feeding. Expression of WT macrophage ABCA1 in ABC1(-/-) mice resulted in a small but significant increase in apoA-I levels starting 2 weeks after transplantation. No further increase in apoAI was observed up to 14 weeks after transplantation. The increase in apoAI was accompanied by a small but significant increase in HDL cholesterol 6 weeks after transplantation. The HDL formed as a consequence of the expression of WT macrophage ABCA1 migrated to the alpha position in a two-dimensional gel electrophoresis. These results demonstrate that monocyte/macrophage ABCA1 contributes to HDL formation; however, the contribution to the overall plasma HDL levels is minimal.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Monocitos
/
Transportadoras de Casetes de Unión a ATP
/
Lipoproteínas HDL
/
Macrófagos
Límite:
Animals
/
Humans
Idioma:
En
Revista:
J Clin Invest
Año:
2001
Tipo del documento:
Article
País de afiliación:
Estados Unidos
Pais de publicación:
Estados Unidos