<
https://www.nationalgeographic.com/premium/article/why-does-covid-19-cause-brain-fog-answer-immune-inflammation-synapse>
"When scientists infected brain organoids—pinhead-size bits of brain tissue
grown in the lab—with the virus that causes COVID, they found that not only
does it spread in neurons in the brain, it also accelerates the destruction of
connections between neurons—called synapses—that are essential for
communication.
These discoveries expand understanding of how SARS-CoV-2 can damage the nervous
system. COVID-19 patients continue to suffer with a range of symptoms,
especially neural and behavioral problems, long after the infection. One such
condition, commonly known as brain fog, causes disorientation, memory loss,
chronic headache, and numbness, and it affects nearly 40 percent of long COVID
patients.
“There are many case reports, even some in our own clinic, of patients who have
symptoms [of brain fog] lasting upwards of a year,” says Ayush Batra, a
neurologist at Northwestern University Feinberg School of Medicine.
Carl Sellgren, a psychiatrist and cellular biologist, and his team at the
Karolinska Institute in Sweden used organoids to study what SARS-CoV-2 does to
brain.
“It was quite striking that very small amounts of the virus could quite rapidly
spread in the organoids and eliminate an excessive number of synapses,” says
Ana Osório Oliveira, a neuroscientist in Sellgren’s team.
Another study found that spike protein—which coats the outer surface of the
virus—directly eliminates synapses causing loss of memory in lab mice by
causing inflammation.
Destroying too many connections between neurons, or over-pruning, may be
causing brain fog in long COVID patients. “This could be one of the many
reasons—probably—why we are observing a range of neurological symptoms, even
after the infection is long gone,” says Samudyata, a postdoctoral researcher at
Karolinska Institute who led the study and only uses one name.
Virus has been found in autopsied brain tissues and throughout the bodies of
patients, who died more than 200 days after contracting COVID-19. It is
evidence that the virus is capable of persisting in organs throughout the body.
“There are some persistent virus reservoirs that can cause a chronic
inflammatory response or autoimmune attack on the brain, which can cause
pruning and brain shrinkage,” says Batra."
Via Violet Blue’s
Pandemic Roundup: November 16, 2023
https://www.patreon.com/posts/pandemic-roundup-92977565
Cheers,
*** Xanni ***
--
mailto:xanni@xanadu.net Andrew Pam
http://xanadu.com.au/ Chief Scientist, Xanadu
https://glasswings.com.au/ Partner, Glass Wings
https://sericyb.com.au/ Manager, Serious Cybernetics
