The amyloid clumps in patients resemble those that are found in people with neurodegenerative diseases such as Alzheimer’s and Parkinson’s.
The cause of the symptoms found in patients with long-COVID may be the amyloid clumps forming in the brain, similar to those found in Alzheimer’s and Parkinson’s.
Long-COVID can persist for months after the infection is over and is characterised by what is commonly referred to as “brain fog” which encompasses multiple possible symptoms such as memory loss, sensory confusion, lack of concentration and severe headaches.
There is evidence that the virus can enter the brain of infected people, but the exact mechanisms that cause these neurological symptoms are still being uncovered.
A team comprised of researchers from Swinburne University of Technology, La Trobe University and Luxembourg University have now found that fragments of proteins from the SARS-CoV-2 virus can form amyloid clumps in the brain.
They resemble the amyloids found in people with neurodegenerative diseases like Alzheimer’s and Parkinson’s disease.
The study published in Nature Communications, also showed that these are highly toxic to brain cells.
“These toxic clumps of protein, or amyloid assemblies, appear to be similar to those found in Alzheimer’s disease and may be responsible for some of the neurological symptoms of long-COVID,” said Dr Nick Reynolds from La Trobe University’s Institute for Molecular Science.
“We suggest that aggregates of SARS-CoV-2 proteins may trigger neurological symptoms in COVID-19 that many call brain fog.”
The authors have cautioned that implications are still unclear, this does not necessarily mean people might have lasting damage or that functions like thinking and memory will be profoundly affected.
Dr Mirren Charnley designed, performed, and analysed the biochemical flow cytometry assays that determine the mechanism of brain cell loss caused by the amyloids, assisted by physical characterisation of amyloids at the Australian Synchrotron.
The postdoctoral researcher from Swinburne said this could help in developing more clarity on how to treat patients with brain fog.
“If further studies are able to prove that the formation of these amyloids is causing long-COVID then anti-amyloid drugs developed to treat Alzheimer’s might be used to treat some of the neurological symptoms of long-COVID,” Dr Charnley said.
