title: Unilateral injection of Aβ25-35in the hippocampus reduces the number of dendritic spines in hyperglycemic rats.
abstract: Alzheimer's disease (AD) is a neurodegenerative process exacerbated by several risk factors including impaired glucose metabolism in the brain that could cause molecular and neurochemical alterations in cognitive regions such as the hippocampus (Hp). Consequently, this process could cause neuronal morphological changes; however, the mechanism remains elusive. We induced chronic hyperglycemia after streptozotocin (STZ) administration. Then, we examined spatial learning and memory using the Morris water maze test and evaluated neuronal morphological changes using the Golgi-Cox stain procedure in hyperglycemic rats that received a Aβ25-35unilateral injection into the Hp. Our results demonstrate that STZ combined with Aβ25-35induced significant deficits in the spatial memory. In addition, we observed a significant reduction in the number of dendritic spines of pyramidal neurons in the dorsal Hp of rats with STZ plus Aβ25-35. In conclusion, the reduced spine density of pyramidal neurons in the CA1 dorsal Hp could produce the spatial memory deficit observed in these animals. These results suggest that hyperglycemia can trigger Aβ-induced neurodegeneration and thus the appearance of AD symptoms would be accelerated. Synapse 68:585-594, 2014. © 2014 Wiley Periodicals, Inc.
authors: Laboratorio de Neuropsiquiatría, Instituto de Fisiología Benemérita Universidad Autónoma de Puebla, Puebla, México.
authors: Zayda
authors: Z
authors: Lazcano
authors: Laboratorio de Neuropsiquiatría, Instituto de Fisiología Benemérita Universidad Autónoma de Puebla, Puebla, México.
authors: Oscar
authors: O
authors: Solis
authors: Laboratorio de Neuropsiquiatría, Instituto de Fisiología Benemérita Universidad Autónoma de Puebla, Puebla, México.
authors: María Elena
authors: ME
authors: Bringas
authors: Laboratorio de Neurofarmacología, Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, Puebla, México.
authors: Daniel
authors: D
authors: Limón
authors: Departamento de Farmacia, Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, Puebla, México.|Laboratorio Experimental de Enfermedades Neurodegenerativas, Instituto Nacional de Neurología y Neurocirugía, Ciudad de México, Distrito Federal, México.|Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de México, Distrito Federal, México.
authors: Alfonso
authors: A
authors: Diaz
authors: Laboratorio de Bioquímica, Instituto Nacional de Enfermedades Respiratorias, Ciudad de México, Distrito Federal, México.
authors: Blanca
authors: B
authors: Espinosa
authors: Departamento de Biología Celular y Tisular, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de México, Distrito Federal, México.
authors: Isabel
authors: I
authors: García-Peláez
authors: Laboratorio de Neuropsiquiatría, Instituto de Fisiología Benemérita Universidad Autónoma de Puebla, Puebla, México.
authors: Gonzalo
authors: G
authors: Flores
authors: Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de México, Distrito Federal, México.
authors: Jorge
authors: J
authors: Guevara
keywords: Alzheimer; animal models; dendritic spine; dorsal hippocampus; hyperglycemia; spatial memory