INIBIOLP   05426
INSTITUTO DE INVESTIGACIONES BIOQUIMICAS DE LA PLATA "PROF. DR. RODOLFO R. BRENNER"
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Effect of reconstituted discoidal lipoproteins on lipid mobilization in two cell lines
Autor/es:
CABALEIRO LV; TOLEDO JD; GARDA HA; GONZALEZ MC
Lugar:
Puerto Madryn, Chubut
Reunión:
Congreso; 46th Annual Meeting Argentine Society for Biochemistry and Molecular Biology XLVI Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB); 2010
Institución organizadora:
Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB)
Resumen:
<!-- /* Font Definitions */ @font-face {font-family:TimesNewRomanPSMT; panose-1:0 0 0 0 0 0 0 0 0 0; mso-font-charset:0; mso-generic-font-family:roman; mso-font-format:other; mso-font-pitch:auto; mso-font-signature:3 0 0 0 1 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:ES-AR; mso-fareast-language:ES;} @page Section1 {size:612.0pt 792.0pt; margin:70.85pt 3.0cm 70.85pt 3.0cm; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> Discoidal high density lipoproteins (dHDL) play a key role in apolipoprotein A-I (apoAI) mediated cell lipid efflux. We have used reconstituted dHDL of different size either containing or not cholesterol (C) with the aim of comparing their ability to modify the cellular distribution between C and cholesteryl esters (CE) as well as to promote cellular efflux of choline-containing phospholipid as phosphatidylcholine (PC) or sphingomyelin (SM). Two cell lines were used, one of them (CHOK1) with limited capacity to store CE, and the second one (Raw 264.7 macrophages) capable to accumulate large amounts of CE until they are transformed in foam cells responsible for the atherosclerotic plaque formation. In RAW cells, dHDL tend to increase the cellular CE/C ratio although it is statistically significant only in the case of C-containing 96 Å discs. On the other hand, in CHO cells lipid-free apoAI and large (120 Å) C-free dHDL decrease the cellular CE/C ratio indicating a lower availability of C to be esterified. With both cell lines, only PC (but not SM) efflux is evoked by apoAI or dHDL although some dependence on the cell type is observed. In RAW cells, apoAI and all dHDL types with the only exception of C-free 96 Å discs promote PC efflux and decrease the cellular PC/SM ratio, but only apoAI and C-free 78 Å discs are active in this process concerning CHO cells.