Analysis of lipid transfer activity between model nascent HDL particles and plasma lipoproteins: implications for current concepts of nascent HDL maturation and genesis.
J Lipid Res
; 51(4): 785-97, 2010 Apr.
Article
em En
| MEDLINE
| ID: mdl-19797257
ABSTRACT
The specifics of nascent HDL remodeling within the plasma compartment remain poorly understood. We developed an in vitro assay to monitor the lipid transfer between model nascent HDL (LpA-I) and plasma lipoproteins. Incubation of alpha-(125)I-LpA-I with plasma resulted in association of LpA-I with existing plasma HDL, whereas incubation with TD plasma or LDL resulted in conversion of alpha-(125)I-LpA-I to prebeta-HDL. To further investigate the dynamics of lipid transfer, nascent LpA-I were labeled with cell-derived [(3 )H]cholesterol (UC) or [(3)H]phosphatidylcholine (PC) and incubated with plasma at 37 degrees C. The majority of UC and PC were rapidly transferred to apolipoprotein B (apoB). Subsequently, UC was redistributed to HDL for esterification before being returned to apoB. The presence of a phospholipid transfer protein (PLTP) stimulator or purified PLTP promoted PC transfer to apoB. Conversely, PC transfer was abolished in plasma from PLTP(-/-) mice. Injection of (125)I-LpA-I into rabbits resulted in a rapid size redistribution of (125)I-LpA-I. The majority of [(3)H]UC from labeled r(HDL) was esterified in vivo within HDL, whereas a minority was found in LDL. These data suggest that apoB plays a major role in nascent HDL remodeling by accepting their lipids and donating UC to the LCAT reaction. The finding that nascent particles were depleted of their lipids and remodeled in the presence of plasma lipoproteins raises questions about their stability and subsequent interaction with LCAT.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Apolipoproteínas B
/
Lipoproteínas de Alta Densidade Pré-beta
/
Lipoproteínas
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
J Lipid Res
Ano de publicação:
2010
Tipo de documento:
Article
País de afiliação:
Canadá