Is amyloid involved in acute neuroinflammation? A CSF analysis in encephalitis

Alzheimers Dement. 2022 Nov;18(11):2167-2175. doi: 10.1002/alz.12554. Epub 2022 Jan 27.

Abstract

Introduction: Several investigations have argued for a strong relationship between neuroinflammation and amyloid metabolism but it is still unclear whether inflammation exerts a pro-amyloidogenic effect, amplifies the neurotoxic effect of amyloid, or is protective.

Methods: Forty-two patients with acute encephalitis (ENC) and 18 controls underwent an extended cerebrospinal fluid (CSF) panel of inflammatory, amyloid (Aβ40, 42, and 38, sAPP-α, sAPP-β), glial, and neuronal biomarkers. Linear and non-linear correlations between CSF biomarkers were evaluated studying conditional independence relationships.

Results: CSF levels of inflammatory cytokines and neuronal/glial markers were higher in ENC compared to controls, whereas the levels of amyloid-related markers did not differ. Inflammatory markers were not associated with amyloid markers but exhibited a correlation with glial and neuronal markers in conditional independence analysis.

Discussion: By an extensive CSF biomarkers analysis, this study showed that an acute neuroinflammation state, which is associated with glial activation and neuronal damage, does not influence amyloid homeostasis.

Keywords: acute inflammation; amyloid; glial cells; neuroinflammation; tau.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alzheimer Disease* / cerebrospinal fluid
  • Amyloid beta-Peptides / metabolism
  • Amyloidogenic Proteins
  • Amyloidosis*
  • Biomarkers / cerebrospinal fluid
  • Encephalitis*
  • Humans
  • Neuroinflammatory Diseases
  • Peptide Fragments / cerebrospinal fluid
  • tau Proteins / cerebrospinal fluid

Substances

  • Amyloid beta-Peptides
  • tau Proteins
  • Biomarkers
  • Amyloidogenic Proteins
  • Peptide Fragments