Effects of COVID-19 on human cognition
COVID-19 appears to be a possible trigger for Alzheimer’s-like dementia. New evidence suggests that SARS-CoV-2 may have lasting effects on brain function, requiring the development of therapeutic strategies for COVID-19-associated cognitive impairment.
A new study led by researchers from the Cleveland Clinic (USA) has uncovered significant overlaps between Alzheimer’s and COVID-19, focusing on neuroinflammation and microvascular injuries. The study was published in the English-language journal “Alzheimer’s Research & Therapy”.
COVID-19 often with neurological symptoms
Reports of neurological complications in people with COVID-19, and so-called Long COVID, are becoming more common, suggesting that SARS-CoV-2 can have lasting effects on brain function. The results of the new study now indicate an overlap between COVID-19 and the brain changes that are common in Alzheimer’s disease, the researchers report.
“While some studies indicated that SARS-CoV-2 directly infects brain cells, others found no evidence of the virus in the brain,” explains study author Dr. Feixiong Cheng from Cleveland Clinic. However, identifying the link between COVID-19 and neurological problems will be critical to developing effective preventive and therapeutic strategies “to cope with the surge in neurocognitive impairment that we expect in the near future.”
What role do genetic factors play?
For the current study, the experts used artificial intelligence using existing data sets from people with Alzheimer’s and COVID-19. They measured the proximity between SARS-CoV-2 host genes / proteins and those associated with multiple neurological diseases, with greater proximity indicating related or common pathways of disease. The researchers also analyzed the genetic factors that enable SARS-COV-2 to infect brain tissue and cells.
Association between COVID-19 and neuroinflammation
While little evidence has been found that the virus targets the brain directly, researchers discovered tight network relationships between the virus and genes / proteins associated with several neurological diseases. Since this was particularly true of Alzheimer’s, it was suggested that COVID-19 could lead to Alzheimer’s-like dementia. To investigate this further, the experts analyzed possible associations between COVID-19 and so-called neuroinflammation and microvascular damage to the brain, which are both hallmarks of Alzheimer’s.
“We discovered that SARS-CoV-2 infection significantly changed Alzheimer’s markers associated with inflammation in the brain and that certain viral entry factors are strongly expressed in cells of the blood-brain barrier,” explains study author Dr. Cheng in a Cleveland Clinic press release.
According to Dr. Cheng points out that the virus can affect multiple genes or signaling pathways involved in neuroinflammation and microvascular damage to the brain, causing Alzheimer’s-like cognitive impairment.
More vulnerable to COVID-19?
The research group also found that people with the greatest genetic risk factor for Alzheimer’s disease (APOE E4 / E4 allele) had decreased expression of antiviral defense genes, which could make them more susceptible to COVID-19.
“Ultimately, we hope to pave the way for research that will lead to testable and measurable biomarkers that can identify patients at greatest risk for neurological complications from COVID-19,” added Dr. Cheng added. The researchers are currently working on using the latest network medicine and artificial intelligence technologies to identify usable biomarkers and new therapeutic targets for COVID-19-associated neurological problems in people with long-term consequences of COVID-19. (as)
Author and source information
This text complies with the requirements of specialist medical literature, medical guidelines and current studies and has been checked by medical professionals.
- Yadi Zhou, Jielin Xu, Yuan Hou, James B. Leverenz, Asha Kallianpur et al.: Network medicine links SARS-CoV-2/COVID-19 infection to brain microvascular injury and neuroinflammation in dementia-like cognitive impairment, in Alzheimer’s Research & Therapy (veröffentlicht 09.06.2021), Alzheimer’s Research & Therapy
- Cleveland Clinic: Cleveland Clinic-led Study Identifies How COVID-19 Linked to Alzheimer’s Disease-like Cognitive Impairment (veröffentlicht 10.06.2021), Cleveland Clinic
This article is for general guidance only and is not intended to be used for self-diagnosis or self-treatment. He can not substitute a visit at the doctor.