Relationship between cytokine levels in the cerebrospinal fluid and 11C-Pittsburgh compound B retention in patients with mild cognitive impairment.

AIM: In the present study, we examined the relationship between cytokine levels in the cerebrospinal fluid (CSF) and11 C-Pittsburgh compound B (PiB) retention in patients with mild cognitive impairment.

METHODS: A total of 33 participants (12 men and 21 women; mean age 76.5 years) with mild cognitive impairment underwent neuropsychological assessments, PiB positron emission tomography and analysis of cytokine levels in the CSF. The CSF levels of 48 cytokines and growth factors were measured using multiplex immunoassays. PiB retention was assessed based on a standardized uptake value ratio. Mild cognitive impairment participants were classified as PiB-positive and PiB-negative, with a cut-off level of 1.4. We compared the CSF cytokine levels and Alzheimer's disease biomarkers, including β-amyloid 1-42, total tau and tau phosphorylated at threonine 181, between the two subgroups, and evaluated the correlation between PiB retention or CSF Alzheimer's disease biomarkers and CSF cytokine levels.

RESULTS: Cytokine levels in the CSF did not differ between the two subgroups. Macrophage inflammatory protein-1β levels in the CSF significantly correlated with PiB retention only in the PiB-positive subgroup, whereas stem cell growth factor-β levels significantly correlated with PiB retention in the PiB-negative subgroup. Furthermore, stem cell growth factor-β levels significantly correlated with total tau and tau phosphorylated at threonine 181 levels in only the PiB-negative subgroup.

CONCLUSION: The present findings suggest that macrophage inflammatory protein-1β and stem cell growth factor-β are associated with chronic inflammatory processes accompanied by amyloid deposition or AD pathophysiology. Geriatr Gerontol Int 2017; 17: 1907-1913.