J Neurol Sci 2002 Oct 15;202(1-2):13
Minagar A, Shapshak P, Fujimura R, Ownby R, Heyes M, Eisdorfer C.
Department of Neurology, Louisiana State University School of Medicine, 71130, Shreveport, LA, USA
Macrophage/microglia (M slashed circle ) are the principal immune cells in the central nervous system (CNS) concomitant with inflammatory brain disease and play a significant role in the host defense against invading microorganisms.
Astrocytes, as a significant component of the blood-brain barrier, behave as one of the immune effecter cells in the CNS as well.
However, both cell types may play a dual role, amplifying the effects of inflammation and mediating cellular damage as well as protecting the CNS.
Interactions of the immune system, M slashed circle, and astrocytes result in altered production of neurotoxins and neurotrophins by these cells.
These effects alter the neuronal structure and function during pathogenesis of HIV-1-associated dementia (HAD), Alzheimer disease (AD), and multiple sclerosis (MS).
HAD primarily involves subcortical gray matter, and both HAD and MS affect sub-cortical white matter.
AD is a cortical disease.
The process of M slashed circle and astrocytes activation leading to neurotoxicity share similarities among the three diseases.
Human Immunodeficiency Virus (HIV)-1-infected M slashed circle are involved in the pathogenesis of HAD and produce toxic molecules including cytokines, chemokines, and nitric oxide (NO).
In AD, M slashed circle s produce these molecules and are activated by beta-amyloid proteins and related oligopeptides.
Demyelination in MS involves M slashed circle that become lipid laden, spurred by several possible antigens.
In these three diseases, cytokine/chemokine communications between M slashed circle and astrocytes occur and are involved in the balance of protective and destructive actions by these cells.
This review describes the role of M slashed circle and astrocytes in the pathogenesis of these three progressive neurological diseases, examining both beneficent and deleterious effects in each disease.