Patients suffering from Covid-19 are experiencing a range of effects on their brains, including loss of smell and taste, confusion, and life-threatening strokes. This has attracted the attention of researchers to study the impact of Covid-19 infection on the brain.
A comprehensive molecular study of the brain tissue from people that succumbed to covid-19 proves that SARS-CoV-2 causes profound molecular alterations in the brain, notwithstanding the absence of the virus in the brain mass. The changes the virus leaves in the brain indicate intense inflammation and disrupted brain circuits observed in Alzheimer’s or other neurodegenerative conditions. the lead author in the study, Tony Wyss-Coray, professor in the School of Medicine, confirmed the findings xnxx.
Up to a third of persons infected with SARS-CoV-2 exhibited brain symptoms like brain fog, fatigue and memory problems. Many individuals experience such symptoms long after recovering from the virus infection. However, the virus’ mechanism of causing these symptoms and its molecular effects on the brain are still unclear. The researchers deployed singer-cell RNA sequencing to study brain tissue samples from 8 patients who succumbed to the covid-19 virus and 14 control samples from those who died of other causes. Surprisingly, the study found significant changes in the brain cells and different types of cells (immune, nerve and support cells) in the brain. Across cell types, covid-19 effects resemble those observed in chronic brain illnesses and exist in genetic variants related to cognition, depression, and schizophrenia.
From the research, viral infections tend to trigger inflammatory reactions throughout the body. These inflammatory responses may cause inflammatory signaling across the blood-brain barrier and consequently trigger neuroinflammation in the brain. The study results may explain the brain fog, fatigue alongside other neurological and psychiatric symptoms linked to covid.
A more extensive study (with nearly 800 participants) compared brain scans from the same people before and after infection with SARS-CoV-2. The scans showed tissue abnormalities and loss of gray matter in people who had the covid disease than in those who did not. The changes mainly affected the areas of the brain related to smell. Neurological experts, commenting on the publication in the journal of nature, said the findings were valuable and unique. They cautioned that the consequences of the changes are not clear. The results do not necessarily imply that people may experience long-lasting damage or that the observed changes profoundly affect memory, thinking, and other functions.
The brain images and cognitive scores of persons with SARS-CoV-2 exhibited changes between the two scans compared to those in the control group. The differences were more significant in older participants. While not all who became infected with the virus showed these differences, the group that had a prior infection on average had:
- A diminished gray matter mass in the brain areas associated with the sense of smell (parahippocampal gyrus and orbitofrontal cortex)
- More tissue damages in the parts linked with the primary olfactory cortex (also connected with the sense of smell)
- A decline in entire brain volume and increase in the volume of cerebrospinal fluid
- A significant drop in the ability to perform complex tasks – linked to atrophy in the area of the brain associated with cognition
According to the team of researchers, the potential mechanisms by which the virus infection might affect the brain include;
- A reduced sensory input particularly related to smell
- Immune reactions or neuroinflammation
- Viral infections to the brain cells