Title : Flavonoids and possible COVID-19 integrative considerations
Flavonoids, abundantly present in fruits and vegetables, have traditionally been documented as being protective against cancer, allergies, metabolic and inflammatory disorders, and cardiovascular diseases, as well as for their antiviral benefits. The last has attracted attention as several computational methods, mostly docking studies, have shown that flavonoids may bind to multiple regions of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) [spike protein, host cell angiotensin-converting enzyme 2 (ACE2) receptor and proteases, such as papain-like protease (PLpro) and main protease (Mpro), also referred to as the 3C-like protease (3CLpro)]. Several flavonoids have low binding energies, both with the SARS-CoV-2 “spike” protein, responsible for internalization, and also with “PLpro” and “Mpro” responsible for transforming the early proteins of the virus into the complex responsible for viral replication, suggesting that these flavonoids could act as prophylactic agents by blocking several mechanisms of viral infections and replications, and thus helping the host cells to resist viral attack. Therefore, we anticipate that flavonoids either alone or in combination with other nutritional substances, antivirals or other drugs, could be a therapeutic tool for either further optimization and development or repositioned for COVID-19 therapeutic treatment.