Amyloid-β Homeostasis Bridges Inflammation, Synaptic Plasticity Deficits and Cognitive Dysfunction in Multiple Sclerosis

• Published in: Frontiers in molecular neuroscience Vol. 10; p. 390
• Main Authors: Stampanoni Bassi, Mario, Garofalo, Sara, Marfia, Girolama A, Gilio, Luana, Simonelli, Ilaria, Finardi, Annamaria, Furlan, Roberto, Sancesario, Giulia M, Di Giandomenico, Jonny, Storto, Marianna, Mori, Francesco, Centonze, Diego, Iezzi, Ennio
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Research Foundation 21.11.2017; Frontiers Media S.A
• Subjects: amyloid-β; Apolipoproteins; Atrophy; Cerebrospinal fluid; Cognitive ability; Cytokines; Demyelination; Hippocampal plasticity; Hippocampus; Homeostasis; IL-10; IL-1β; IL-8; Inflammation; inflammatory cytokines; Interleukin 1; Interleukin 1 receptor antagonist; Interleukin 1 receptors; Interleukin 10; Interleukin 12; Interleukin 8; Kinases; Memory; Multiple sclerosis; Neurodegeneration; Neurological diseases; Neurology; Neuroscience; NMR; Nuclear magnetic resonance; Proteins; Substantia grisea; Synaptic plasticity; Tumor necrosis factor-α; γ-Interferon; Italy; IL-1ra; hippocampus; amyloid-β; inflammatory cytokines; synaptic plasticity; IL-8; IL-10
• ISSN: 1662-5099; 1662-5099
• DOI: 10.3389/fnmol.2017.00390

Cognitive deficits are frequently observed in multiple sclerosis (MS), mainly involving processing speed and episodic memory. Both demyelination and gray matter atrophy can contribute to cognitive deficits in MS. In recent years, neuroinflammation is emerging as a new factor influencing clinical course in MS. Inflammatory cytokines induce synaptic dysfunction in MS. Synaptic plasticity occurring within hippocampal structures is considered as one of the basic physiological mechanisms of learning and memory. In experimental models of MS, hippocampal plasticity is profoundly altered by proinflammatory cytokines. Although mechanisms of inflammation-induced hippocampal pathology in MS are not completely understood, alteration of Amyloid-β (Aβ) metabolism is emerging as a key factor linking together inflammation, synaptic plasticity and neurodegeneration in different neurological diseases. We explored the correlation between concentrations of Aβ and the levels of some proinflammatory and anti-inflammatory cytokines (interleukin-1β (IL-1β), IL1-ra, IL-8, IL-10, IL-12, tumor necrosis factor α (TNFα), interferon γ (IFNγ)) in the cerebrospinal fluid (CSF) of 103 remitting MS patients. CSF levels of Aβ were negatively correlated with the proinflammatory cytokine IL-8 and positively correlated with the anti-inflammatory molecules IL-10 and interleukin-1 receptor antagonist (IL-1ra). Other correlations, although noticeable, were either borderline or not significant. Our data show that an imbalance between proinflammatory and anti-inflammatory cytokines may lead to altered Aβ homeostasis, representing a key factor linking together inflammation, synaptic plasticity and cognitive dysfunction in MS. This could be relevant to identify novel therapeutic approaches to hinder the progression of cognitive dysfunction in MS.