ABSTRACT
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.
ABSTRACT
Since the first cases the coronavirus disease caused by SARS-CoV-2 (COVID-19) reported in December 2019, worldwide continuous efforts have been placed both for the prevention and treatment of this infectious disease. As new variants of the virus emerge, the need for an effective antiviral treatment continues. The concept of preventing SARS-CoV-2 on both pre-entry and post-entry stages has not been much studied. Therefore, we compared the antiviral activities of three antiviral drugs which have been currently used in the clinic. In silico docking analyses and in vitro viral infection in Vero E6 cells were performed to delineate their antiviral effectivity when used alone or in combination. Both in silico and in vitro results suggest that the combinatorial treatment by favipiravir and umifenovir or camostat mesylate has more antiviral activity against SARS-CoV-2 rather than single drug treatment. These results suggest that inhibiting both viral entry and viral replication at the same time is much more effective for the antiviral treatment of SARS-CoV-2.
ABSTRACT
Ribavirin is a guanosine analog and has a broad-spectrum antiviral activity against RNA viruses. Based on this, we aimed to show the anti-SARS-CoV-2 activity of this drug molecule via in vitro, in silico and molecular techniques. Ribavirin showed antiviral activity in Vero E6 cells following SARS-CoV-2 infection. In silico analysis suggested that Ribarivin has a broad-spectrum impact on Vero E6 cells. According to the detailed molecular techniques, Ribavirin was shown to decrease TMPRSS2 expression both at mRNA and protein level 48 hours after treatment. The suppressive effect of Ribavirin in ACE2 protein expression was shown to be dependent on cell types. Finally, proteolytic activity assays showed that Ribavirin also showed an inhibitory effect on TMPRSS2 enzyme. As a conclusion, Ribavirin is a potential antiviral drug for the treatment against SARS-CoV-2, and it interferes with the effect of TMPRSS2 and ACE2 expression.
