Dialogue between Neuroinflammation and Neurodegenerative Diseases in COVID-19.

Chowdhury, Bisruta; Sharma, Apoorva; Satarker, Sairaj; Mudgal, Jayesh; Nampoothiri, Madhavan

It has now been almost a year since the emergence of the deadly SARS-CoV-2 with millions of people losing their lives due to resultant COVID-19. Apart from the well-known consequences of respiratory illnesses, it has even effortlessly mapped itself into the nervous system through routes like blood, CSF, neurons, and olfactory cells. Interestingly, the interaction of SARS-CoV-2 with the nervous system cells like neurons, microglia, and astrocytes has been a factor to worsen COVID-19 through its neuroinflammatory actions. The release of cytokines due to astrocyte and microglial activation could progress towards the most anticipated cytokine storm proving to be detrimental in the management of COVID-19. Such hyper-inflammatory conditions could make the BBB vulnerable, encouraging excessive viral particles into the CNS, leading to further neurodegenerative pathologies like Alzheimer's disease, Parkinson's disease, Creutzfeldt-Jakob disease, and Multiple Sclerosis. Excessive neuroinflammation and neurodegeneration being the anticipated root causes of these multiple conditions, it is also essential to look into other factors that synergistically enhance the worsening of these diseases in COVID-19 patients for which additional studies are essential.