Experimental strategies for investigating COVID-19-induced anosmia: is there a neurodegenerative component involved?

The pandemic caused by the COVID-19 virus has led to the saturation of health systems around the world due to the severity of some of its respiratory symptoms. However, the report of patients about the onset of anosmia (decreased or loss of olfactory sense) with the course of the pathology, leads to the hypothesis of the participation of a neural and, perhaps neurodegenerative component of SARS-COV-2. In addition to a common symptom in respiratory viral infections, anosmia is also an early clinical sign of neuroegenerative diseases, such as Alzheimer's, Multiple Sclerosis and Parkinson's. The neural pathway that leaves the olfactory epithelium and reaches the olfactory bulb in the central nervous system is a neurogenic niche with regenerative capacity maintained in adulthood. Besides that, this pathway has an important cognitive and emotional role due to its connections with limbic areas such as piriform, entohrinal and tonsil cortex. The present work aims to study, using in vitro and in vivo strategies, the neural invasive mechanisms of COVID-19 in the sensory olfactory system, in addition to characterizing possible therapeutic targets and behavioral consequences associated with infection.