Affiliations: [a] Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA | [b] Department of Biochemistry, University of Oklahoma Health Science Center, Oklahoma City, OK, USA | [c] Oklahoma Center for Neuroscience, University of Oklahoma Health Science Center, Oklahoma City, OK, USA | Institut für Biochemie und Molekularbiologie I, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, D-40225 Düsseldorf, Germany Tel.: +49 211 811 5358; Fax: +49 211 811 3029; E-mail: polidori@uni-duesseldorf.de
Abstract: Many neurological diseases, including Alzheimer's disease (AD) and amyotrophic lateral sclerosis (ALS), are now recognized to share atypical inflammatory reactions as a major pathological feature. Neuroinflammation can both be a cause, and a consequence, of chronic oxidative stress. Cytokine-stimulated microglia generate copious amounts of reactive oxygen and reactive nitrogen species, creating a stress upon ambient neurons. Conversely, oxidants can stimulate pro-inflammatory gene transcription in glia, leading to various inflammatory reactions. This review compares literature regarding neuroinflammation in AD and ALS, with special emphasis on roles played by tumor necrosis factor alpha (TNFα) and aberrant arachidonic acid metabolism in the genesis of chronic oxidative conditions. Based on our observations made in the G93A-SOD1 mouse model of ALS, and a body of Alzheimer's disease findings, we hypothesize a prominent pathological role for the TNFα-signaling axis and neuroinflammation in the pathogenesis of both diseases. A discussion is made regarding the relevance of neuroinflammation to potential therapeutic implications for both ALS and AD.
