O-glycosylation in sprouting neurons in Alzheimer disease, indicating reactive plasticity
Por:
Espinosa B., Zenteno R., Mena R., Robitaille Y., Zenteno E., Guevara J.
Publicada:
1 ene 2001
Resumen:
Reactive plasticity, including axonal and dendritic sprouting and reactive synaptogenesis, has been proposed to contribute to the pathogenesis of several neurological disorders. This work was aimed at identifying the possible role of protein glycosylation in the brain from patients with Alzheimer disease (AD), using lectin histochemistry, as determinants of reactive plasticity. Results indicate an increase in the production of cryptic O-glycosidically linked proteins (NeuAc?2,6 Gal?1,3GalNAc?1,0 Ser/Thr or sialyl-T-antigen) in neuritic sprouting in AD brains as determined by positive labeling with Amaranthus leucocarpus (ALL, T-antigen-specific) and Macrobrachium rosenbergii (MRL, specific for NeuAc5,9Ac2) lectins. Immunohistochemistry indicated that lectin staining was specific for the synaptic sprouting process (meganeurites) in AD. These results were confirmed using anti-synaptophysin and anti-GAP 43 antibodies, which recognized meganeurites and dystrophic neurites around amyloid-? deposits. In normal control brains, labeling with the aforementioned lectins was restricted to microvessels. Control experiments with neuraminidase-treated brain samples revealed positivity to the lectin from Arachis hypogaea (PNA), which is specific for galactose. Our results suggest specific O-glycosylation patterns of proteins closely related to neuronal plasticity in AD.
Filiaciones:
Espinosa B.:
Departamento de Bioquímica, Inst. Nac. de Enferm. Respiratorias, México City, Mexico
Zenteno R.:
Departamento de Bioquímica, Inst. Nac. de Enferm. Respiratorias, México City, Mexico
Mena R.:
Depto. Fisiologia Biofisica N., CINVESTAV, Mexico City, Mexico
Robitaille Y.:
Department de Neuropathologie, Inst. de Geriatrie de Montreal, Montreal, Que., Canada
Zenteno E.:
Laboratorio de Inmunología, Departamento de Bioquímica, Facultad de Medicina, UNAM, Mexico City, Mexico
Guevara J.:
Depto. de Neuropatología, Inst. Nacional de Neurología, Mexico City, Mexico
Depto. de Neuropatología, Inst. Nacional de Neurología, Insurgentes Sur 3877, La Fama, C.P. 14269, Mexico City, Mexico
All Open Access; Bronze
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