[en] This article gives a comprehensive overview of cytokine and other inflammation associated protein levels in plasma, serum and cerebrospinal fluid (CSF) of patients with Alzheimer's disease (AD) and mild cognitive impairment (MCI). We reviewed 118 research articles published between 1989 and 2013 to compare the reported levels of 66 cytokines and other proteins related to regulation and signaling in inflammation in the blood or CSF obtained from MCI and AD patients. Several cytokines are evidently regulated in (neuro-) inflammatory processes associated with neurodegenerative disorders. Others do not display changes in the blood or CSF during disease progression. However, many reports on cytokine levels in MCI or AD are controversial or inconclusive, particularly those which provide data on frequently investigated cytokines like tumor necrosis factor alpha (TNF-α) or interleukin-6 (IL-6). The levels of several cytokines are possible indicators of neuroinflammation in AD. Some of them might increase steadily during disease progression or temporarily at the time of MCI to AD conversion. Furthermore, elevated body fluid cytokine levels may correlate with an increased risk of conversion from MCI to AD. Yet, research results are conflicting. To overcome interindividual variances and to obtain a more definite description of cytokine regulation and function in neurodegeneration, a high degree of methodical standardization and patients collective characterization, together with longitudinal sampling over years is essential.
Disciplines :
Neurology
Author, co-author :
Brosseron, Frederic; German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
Krauthausen, Marius; Clinic and Polyclinic for Neurology, Clinical Neuroscience Unit, University Hospital Bonn, Bonn, Germany
Kummer, Markus; Clinic and Polyclinic for Neurology, Clinical Neuroscience Unit, University Hospital Bonn, Bonn, Germany
HENEKA, Michael ; German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany ; Clinic and Polyclinic for Neurology, Clinical Neuroscience Unit, University Hospital Bonn, Bonn, Germany ; German Center for Neurodegenerative Diseases (DZNE), Clinical Neuroscience Unit, Clinic and Polyclinic for Neurology, Bonn, Germany
External co-authors :
yes
Language :
English
Title :
Body fluid cytokine levels in mild cognitive impairment and Alzheimer's disease: a comparative overview.
Funding This work was founded by the German Center for Neurodegenerative Diseases (DZNE e.V.) within the Helmholtz Association, by the Deutsche Forschungsgemeinschaft (DFG, Klinische Forscherguppe 177, TP4) and the EU-FP7 consortium INMIND.
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