Title:Brain local and regional neuroglial alterations in Alzheimer´s Disease: cell types, responses and implications.
Volume: 13
Issue: 4
Author(s): Adolfo Toledano, María-Isabel Álvarez, Adolfo Toledano-Díaz, José-Joaquín Merino and José Julio Rodríguez
Affiliation:
Keywords:
Alzheimer’s disease, astrogliosis, glial plasticity, glial neurodegeneration/neuroprotection, microgliosis, neuroglial
cells, reactive neuroglial cells.
Abstract: From birth to death, neurons are dynamically accompanied by neuroglial cells in a very
close morphological and functional relationship. Three families have been classically considered
within the CNS: astroglia, oligodendroglia and microglia. Many types/subtypes (including NGR2+
cells), with a wide variety of physiological and pathological effects on neurons, have been described
using morphological and immunocytochemical criteria. Glio-glial, glio-neuronal and neuro-glial cell signaling and gliotransmission
are phenomena that are essential to support brain functions. Morphofunctional changes resulting from the
plasticity of all the glial cell types parallel the plastic neuronal changes that optimize the functionality of neuronal circuits.
Moreover, neuroglia possesses the ability to adopt a reactive status (gliosis) in which, generally, new functions arise to
improve and restore if needed the neural functionality. All these features make neuroglial cells elements of paramount importance
when attempting to explain any physiological or pathological processes in the CNS, because they are involved in
both, neuroprotection/neurorepair and neurodegeneration. There exist diverse and profound, regional and local, neuroglial
changes in all involutive processes (physiological and pathological aging; neurodegenerative disorders, including Alzheimer
´s disease –AD-), but today, the exact meaning of such modifications (the modifications of the different neuroglial
types, in time and place), is not well understood. In this review we consider the different neuroglial cells and their responses
in order to understand the possible role they fulfill in pathogenesis, diagnosis and treatment (preventive or palliative)
of AD. The existence of differentiated and/or concurrent pathogenic and neuro-protective/neuro-restorative astroglial
and microglial responses is highlighted.
