MODIFICAZIONI MICROTUBULARI OSSIDATIVO-INDOTTE IN UNA LINEA DI CELLULE DI SCHWANNOMA DI RATTO SOTTOPOSTE A CONDIZIONI DI IPERGLICEMIA SPERIMENTALE

The neuropathies of the peripheral and central nervous systems can be caused by hyper -glycemia, a consequence of the deregulation of glucose, resulting in an increase in reactive
oxygen species, with subsequent cellular lesions and impairment of cytoskeletal components
(Maritim et al. 2003; Allen et al. 2005; Drel et al. 2006; Gadau et al., 2009). Microtubules, one
component of the cytoskeleton, are composed of heterodimers of α- and α-tubulin, mainly
α-tubulin, may receives diverse post-translational modifications, consisting in tyrosination,
detyrosination, acetylation, nitrotyrosination, polyglycylation, polyglutamylation, phosphori -lation, palmytoylation (Westermann and Weber, 2003; Fukushima et al., 2009). in the present
work attention has been paid on the possible nitrosative effect of high glucose conditions on
microtubular network in a rat shwannoma cell line. Cells incubated for 72hrs in the presen-ce of 180 mM D-glucose revealed alterations in cell morphology, growth rate and catalase
activity in comparison with controls. in addition, an increase in acetylated α-tubulin and ni -trotyrosine and a downregulation of total, tyrosinated and detyrosinated α-tubulin was found
with Western blot analysis and immunofluorescence. no significant changes in other cytoske -letal components such as actin and GFAP was seen. our work underlined that high glucose
can selectively affects microtubular network in schwannoma cells, exerting its detrimental
effect either through a nitrosylation of tubulin or through the possible inhibition of deacetyla -se enzymes, with subsequent impairment of microtubular functionality.