Mitochondria in the Cerebral and Cerebellar Cortex in Alzheimer’s Disease, Target for a Therapeutic Approach

Abstract

Alzheimer’s disease remains the main cause of dementia in advanced age worldwide. Among the etiopathological background of the disease mitochondrial alterations may play a crucial role, given that they are closely related to metabolic and energy deficiency in neurons, glia, and endothelial cells in Alzheimer’s disease and other neurodegenerative disorders. In a series of morphological and morphometric studies of mitochondria in the cerebrum and the cerebellar cortex in Alzheimer’s disease, by electron microscopy, we described marked morphological and morphometric alterations. The most frequent ultrastructural alterations of the mitochondria consist of disruption of the cristae, accumulation of osmiophilic material, and marked changes of shape and size in comparison with the normal controls. Mitochondrial alterations were particularly prominent in dendritic profiles and dendritic spines. The ultrastructural study of a substantial number of neurons in the cerebellum revealed that mitochondrial alterations do not coexist, as a rule, with the typical Alzheimer’s pathology, such as cytoskeletal alterations, amyloid deposits, and tau pathology, though they are frequently observed coexisting with alterations of the cisternae of the Golgi apparatus. Therapeutical regimes targeting mitochondria may be beneficial in early cases of Alzheimer’s disease.