Dendritic pathology in Alzheimer's disease.

Dendritic pathology and decrease of dendritic spine density are prominent phenomena in early cases of Alzheimer's disease, which correlate significantly with the progressive decline of the mental faculties. In previous studies we have described the pathological alterations of the dendrites and the dendritic spines in the prefrontal area of the cortex and the cerebellum. In this study we attempted to describe the morphological alterations of the dendrites and the dendritic spines, quantifying them in the acoustic and the visual cortices of eleven cases of Alzheimer's disease, applying Golgi staining and electron microscopy. In addition, describing also the ultrastructural changes of the mitochondria in the dendritic profiles and the dendritic spines we noticed that mitochondrial pathology correlates substantially with the dystrophic dendrites, the loss of dendritic branches and the pathological alteration of the dendritic spines. We would hypothesize that mitochondrial alterations may play a very important role in dendritic degeneration and the loss of dendritic spines and we should have thought that therapeutic strategies protecting the mitochondria may be beneficial in Alzheimer's disease.