MOPHOLOGICAL AND BIOCHEMICAL CHANGES INDUCED BY ACUDE OXIDATIVE STRESS IN OLIGODENTROCYTES (OLG)

FERNANDEZ GAMBA AC, LEAL MC, WILLIAMS A, DETULLIO M, ROHER A, MORELLI L, CASTAÑO EM

Puerto Madryn

Congreso; XLVI Reunion Anual-Sociedad Argentina de Investigacion en Bioquimica y Bologia Molecular; 2010

Sociedad Argentina de Investigacion en Bioquimica y Biologia Molecular

Aims 1) To characterize the morphological changes induced by reactive oxygen species (ROS) in primary cultures of OLG 2) To analyze the OLG proteome after acute ROS induction 3) To study the role of CRMP2, a protein involved in axonal guidance, in this process Methods 1) Exposure of primary OLG cultures to 3-nitropropionic acid (3-NP) for 1 h. Detection of ROS and cell viability by fluorescent dyes. Confocal microscopy (CM) of myelin basic protein (MBP) and tubulin expression. Morphological analysis by Branching Index (BI) and intersections at distance from soma 2) Proteomic analysis by 2D-DIGE, trypsin digestion and mass spectrometry. 3) Characterization of CRMP2 isoforms and phosphorylation by Western blot. Cellular expression of CRMP2 by CM. Results 1) 3-NP induced ROS production, reduced the number of peripheral processes indicating significant shortening, as assessed by tubulin and MBP immunofluorescence. 2) Proteomic analysis showed increased CRMP2 and vimentin (fold 1.75 and 2.19) and reduced ribosomal protein SA (fold 0.2) in 3-NP treated OLG as compared to control. 3) After 3-NP treatment CRMP2 phosphorylated isoforms increased 27% and the BI reduction was reverted by Y27632, a Rho kinase inhibitor. Conclusions Rho kinase pathway activation and CRMP2 phosphorylation may be involved in the retraction of OLG peripheral processes induced by acute, non-lethal oxidative stress.