Taste and Smell Disorders in COVID-19 Patients: Role of Interleukin-6.

The rapid recovery of smell and taste functions in COVID-19 patients could be attributed to a decrease in interleukin-6 levels rather than central nervous system ischemic injury or viral damage to neuronal cells. To correlate interleukin-6 levels in COVID-19 patients with olfactory or gustatory dysfunctions and to investigate the role of IL-6 in the onset of these disorders, this observational study investigated 67 COVID-19 patients with taste or smell disorders or both, who did not require intensive care admission, admitted at COVID Hospital of Policlinico of Bari from March to May 2020. Interleukin-6 was assayed in COVID-19 patients with taste or smell disturbances at the time of admission and at the time of swab negativization.

Red wine extract prevents neuronal apoptosis in vitro and reduces mortality of transgenic mice.

In this work, we have investigated the effects of nutritional antioxidants as antidegenerative agents on glutamate-induced apoptosis in primary cultures of cerebellar granule neurons (CGNs). Glutamate-induced apoptosis is also associated with intracellular [Ca(2+)]i overload, generation of reactive oxygen species (ROS), depression of cell energy metabolism, cytochrome c release, and increase in caspase-3 activity. Pretreatment (3 h) with red wine extract (5 microg/mL) and ascorbic acid (30 microM) blocks glutamate-induced apoptosis in CGNs.

Caffeic acid phenethyl ester blocks apoptosis induced by low potassium in cerebellar granule cells.

Primary cultures of cerebellar granule neurons (CGNs) were prepared from 8-day-old Wistar rats, and maintained in an appropriate medium containing a high (25 mM) concentration of KCl. To induce apoptosis, culture medium was replaced with serum-free medium (containing 5mM KCl) 8 days after plating. Apoptosis was measured by the terminal deoxynucleotidyl transferase-mediated dUTP-fluorescein nick end-labeling (TUNEL) method, and by flow cytometry.