Hemin shows antiviral activity in vitro, possibly through suppression of viral entry mediators

Heme oxygenase-1 (HO-1) is a stress-induced enzyme that catalyzes the breakdown of heme into biliverdin, carbon monoxide, and iron. Targeting HO-1 to treat severe COVID-19 has been suggested by several groups, yet the role of HO-1 in SARS-CoV-2 infection remains unclear. Based on this, we aimed to investigate the antiviral activity of Hemin, an activator of HO-1. Infectivity of SARS-CoV-2 was decreased in Vero E6 cells treated with Hemin. Hemin also decreased TMPRSS2 and ACE2 mRNA levels in non-infected cells, possibly explaining the observed decrease in infectivity. TMPRSS2 protein expression and proteolytic activity were decreased in Vero E6 cells treated with Hemin. Besides that, experimental studies supported with in silico calculations. Overall, our study supports further exploration of Hemin as a potential antiviral and inflammatory drug for the treatment of COVID-19.