Glial reactivity in the cerebellum of Solanum bonariense L. intoxicated bovines

VERDES JM; MORAñA A; BATTES D; MáRQUEZ M; PUMAROLA M; GIANNITTI F; ODRIOZOLA E; WEBER N; GUIDI MG; PORTIANSKY EL; GIMENO EJ

Lisboa

Encuentro; II Iberic Meeting of Veterinary Pathology.; 2011

Solanum bonariense, a South American native shrub has been associated with outbreaks of cerebellar dysfunction in cattle due to cerebellar cortical degeneration. Histological lesions include Purkinje cell perikaryal vacuolation, axonal swelling, gliosis and progressive cell death. Ultrastructurally, accumulation of electron-dense residual bodies in the perikarya and axons of affected Purkinje cells was described. The goal of the present study was to immunohistochemically characterize the glial cell reaction observed in the cerebellum of S. bonariense-intoxicated cattle. Formalin-fixed paraffin-embedded cerebella from seven natural and experimentally intoxicated bovines and of two controls were sectioned and immunostained either with a polyclonal rabbit anti-glial fibrillary acidic protein (GFAP), a polyclonal rabbit anti-S-100 protein and the monoclonal anti human-S100â antibodies. GFAP immunohistochemistry was performed using a peroxidase-labelled polymer system and diaminobenzidine as a chromogen. Triple immunofluorescent technique was carried out for detection of GFAP and S-100â, plus DAPI for nuclei detection; samples were observed under confocal microscopy. A remarkable increase in the number of Bergmann and other astrocytes (astrocytosis) was observed around damaged Purkinje cells and in the molecular layer in the cerebella of affected animals. Small round S100â+ cells, normally aligned along Purkinje cells in control animals, were increased in number and showed a disordered distribution pattern throughout the molecular layer. Most of these cells were negative against S-100; however, a small number of cells displayed co-localization of both S-100 and S-100â antigens. The present study contributes to understand the fine gliofilament regulation in reactive astrocytosis observed in the cerebellum of S. bonariense-intoxicated bovines.