INIBIOLP   05426
INSTITUTO DE INVESTIGACIONES BIOQUIMICAS DE LA PLATA "PROF. DR. RODOLFO R. BRENNER"
Unidad Ejecutora - UE
artículos
Título:
Effect of reconstituted discoidal high density lipoproteins on lipid mobilization in RAW 264.7 and CHOK1 cells
Autor/es:
TOLEDO JD; CABALEIRO LV; GARDA HA; GONZALEZ MC
Revista:
JOURNAL OF CELLULAR BIOCHEMISTRY
Editorial:
WILEY-LISS, DIV JOHN WILEY & SONS INC
Referencias:
Lugar: New York; Año: 2011
ISSN:
0730-2312
Resumen:
Reconstituted discoidal high density lipoproteins (rHDL) resemble
nascent HDL, which are formed at the early reverse cholesterol
transport steps, and constitute the initial cholesterol (Chol)
acceptors from cell membranes. We have used different sized rHDL
containing or not Chol, to test their abilities to promote cholesterol
and phospholipid efflux from two different cell lines: Raw 264.7
macrophages and CHOK1 cells. All rHDL and lipid-free apolipoprotein A-I
(apoA-I) were found to be bound to CHO and RAW cells. In RAW cells, a
positive correlation between cellular binding and Chol removal was
found for 78 and 96 Å rHDL. Chol-free rHDL were more effective than
Chol-containing ones in binding to RAW cells and promoting Chol
removal. These results were more evident in the 96 Å rHDL. On the other
hand, rHDL binding to CHO cells was relatively independent of disc size
and Chol content. In spite of the fact that apoA-I and rHDL promoted
Chol efflux from both cellular lines, only in CHOK1 cells this result
was also associated to decrease Chol esterification. Among
choline-containing phospholipids, only phosphatidylcholine (PC) (but
not sphingomyelin) was detected to be effuxed from both cellular lines.
With the only exception of Chol-free 96 Å discs, the other rHDL as well
as apoA-I promoted PC efflux from RAW cells. Chol-containing rHDL were
more active than Chol-free ones of comparable size to promote PC efflux
from RAW macrophages. Regarding CHO cells, only apoA-I and Chol-free 78
Å rHDL were active enough to remove PC. J. Cell. Biochem. © 2011 Wiley
Periodicals, Inc.