CYSTEAMINE GLIOPATHY IN-SITU - A CELLULAR STRESS MODEL FOR THE BIOGENESIS OF ASTROCYTIC INCLUSIONS

In cultured astroglia, cysteamine induces the accumulation of peroxida se-positive cytoplasmic inclusions in the context of a generalized cel lular stress response. In the present study, systemic cysteamine admin istration over a 3 week period induced HSP27, 72, 90, and GRP94 (stres s proteins) in astrocytes and significantly increased numbers of perox idase-positive astrocytic inclusions in the various brain regions rela tive to controls. Similar patterns of HSP expression were also observe d at 24 hours following cysteamine treatment indicating that cellular stress may be a very proximal event in the biogenesis of the astrocyti c inclusions. The topography of glial peroxidase activity may provide a ''map'' of central nervous system regions particularly prone to oxid ative stress during normal aging and under pathologic conditions.