Astrocyte response to Junin virus infection

NEUROSCIENCE LETTERS

卷:445

Article

Pozner, Roberto G.²  Collado, Soledad¹  Jaquenod de Giusti, Carolina¹  Ure, Agustin E.¹  Biedma, Marina E.¹  Romanowski, Victor¹  Schattner, Mirta²  Gomez, Ricardo M.¹ 

[1] Natl Univ La Plata, CONICET, CCT La Plata, Inst Mol Biol & Biotechnol, RA-1900 La Plata, Argentina

[2] Natl Acad Med, Haematol Res Inst, Thrombosis Lab 1, RA-1425 Buenos Aires, DF, Argentina

关键词: Cultured astrocytes;    Viral infection;    GFAP;    iNOS;    NO;   

DOI  :  10.1016/j.neulet.2008.08.059

来源: Elsevier

【 摘 要 】

In a previous study of experimental murine encephalitis induced by Junin virus (JV), an arenavirus, we showed increased expression of iNOS by unidentified cells, concomitant with the astrocyte reaction. The specific inhibition of iNOS was associated with greater mortality but lower astrocytosis, suggesting that the protective role of nitric oxide (NO) synthesized by iNOS was related to enhanced astrocyte activation, representing a beneficial cellular response to virus-induced central nervous system damage. In the present work, cultured astrocytes were used to study whether JV infection could trigger iNOS expression and assess its eventual relationship with viral replication, glial fibrilary acidic protein (GFAP) expression levels and the presence of apoptosis. We found that JV infection of astrocytes did not induce apoptosis but produced both increased iNOS synthesis, detected by immunocytochemistry and fluorescence activated cell sorting (FACS) analysis, and increased NO, which was indirectly measured by nitrite/nitrate levels. These changes occurred early relative to the increases in GFAP expression, as detected by immunocytochemistry, FACS analysis and RT-PCR. The fact that iNOS inhibition abolished enhanced GFAP expression in infected monolayers suggests that NO was directly involved. In addition, iNOS inhibition enhanced virus replication. Together with data from confocal microscopy, these results suggest that JV induces iNOS expression in infected astrocytes and that the resulting NO has an important role both in reducing viral replication and in enhancing subsequent astrocyte activation. (C) 2008 Elsevier Ireland Ltd. All rights reserved.

【 授权许可】

Free