Alzheimer's-like signaling in brains of COVID-19 patients

Alzheimers Dement. 2022 May;18(5):955-965. doi: 10.1002/alz.12558. Epub 2022 Feb 3.

Abstract

Introduction: The mechanisms that lead to cognitive impairment associated with COVID-19 are not well understood.

Methods: Brain lysates from control and COVID-19 patients were analyzed for oxidative stress and inflammatory signaling pathway markers, and measurements of Alzheimer's disease (AD)-linked signaling biochemistry. Post-translational modifications of the ryanodine receptor/calcium (Ca2+ ) release channels (RyR) on the endoplasmic reticuli (ER), known to be linked to AD, were also measured by co-immunoprecipitation/immunoblotting of the brain lysates.

Results: We provide evidence linking SARS-CoV-2 infection to activation of TGF-β signaling and oxidative overload. The neuropathological pathways causing tau hyperphosphorylation typically associated with AD were also shown to be activated in COVID-19 patients. RyR2 in COVID-19 brains demonstrated a "leaky" phenotype, which can promote cognitive and behavioral defects.

Discussion: COVID-19 neuropathology includes AD-like features and leaky RyR2 channels could be a therapeutic target for amelioration of some cognitive defects associated with SARS-CoV-2 infection and long COVID.

Keywords: Alzheimer's disease; COVID-19; calcium; ryanodine receptor; tau pathology.

MeSH terms

  • Alzheimer Disease* / genetics
  • Brain / pathology
  • COVID-19* / complications
  • Calcium Signaling / physiology
  • Humans
  • Post-Acute COVID-19 Syndrome
  • Ryanodine Receptor Calcium Release Channel / genetics
  • Ryanodine Receptor Calcium Release Channel / metabolism
  • SARS-CoV-2

Substances

  • Ryanodine Receptor Calcium Release Channel