COVID-19 Infection in Crucial Brain Regions May Lead To Accelerated Brain Aging

COVID-19 has numerous impacts on the central nervous system. For instance, 20-30% of COVID-19 patients report a lingering psychological condition known as “brain fog” where individuals suffer from symptoms such as memory loss, difficulty in concentrating, forgetting daily activities, difficulty in selecting the right words, taking longer than usual time to complete a regular task, disoriented thought processes and emotional numbness.

The coronavirus infection can cause long-term and irreversible damage to the brain, particularly in the elderly and other vulnerable populations. Several brain imaging studies on COVID-19 victims and survivors have confirmed the formation of microbleed lesions in deeper brain regions involved in cognition and memory. In this review, researchers have critically evaluated the possible chronic neuropathological outcomes in aging and comorbid populations if timely therapeutic intervention is not implemented. Cerebral microbleeds are emerging neuropathological signatures frequently identified in individuals suffering from depressive syndromes, chronic stress, type II diabetes, and other age-associated comorbidities. Based on their earlier findings, the Houston Methodist investigators discuss how COVID-19-induced microhemorrhagic lesions may exacerbate DNA damage in affected brain cells, resulting in neuronal senescence and activation of cell death mechanisms, which ultimately impact brain microstructure-vasculature. These pathological phenomena resemble the hallmarks of neurodegenerative diseases like Alzheimer’s and Parkinson’s and are likely to aggravate advanced-stage dementia, as well as cognitive and motor deficits. “Importantly, individuals over the age of 60 with pre-existing neuropathological conditions might be at the highest risk of developing chronic neurodegeneration,” said Joy Mitra, PhD, an instructor with the Center for Neuroregeneration and lead author of the study. More severe long-term effects include predispositions for Alzheimer’s, Parkinson’s and related neurodegenerative diseases, as well as cardiovascular disorders due to internal bleeding and blood clotting-induced lesions in the part of the brain that regulates our respiratory system, following the COVID-19 symptoms. Additionally, cellular aging is thought to be accelerated in COVID-19 patients. A plethora of cellular stresses inhibit the virus-infected cells from undergoing their normal biological functions and let them enter into “hibernation mode” or even die completely. The study also suggests various strategies to improve some of these long-term neuropsychiatric and neurodegenerative outcomes, as well as outlines the importance of the therapeutic regimen targeting hemorrhage-induced neurotoxicity in combination with various FDA-approved drugs that may prove successful to fight against COVID-19. However, given the ever-evolving nature of this field, associations like the ones described in this review show the fight against COVID-19 is far from over, said the investigators, and reinforce the message that getting vaccinated and maintaining proper hygiene are key in trying to prevent such long-term and detrimental consequences.