Comparison of anti-SARS-CoV-2 activity and intracellular metabolism of remdesivir and its parent nucleoside

Remdesivir, a monophosphate prodrug of nucleoside analog GS-441524, is widely used for the treatment of moderate to severe COVID-19. It has been suggested to use GS-441524 instead of remdesivir in the clinic and in new inhalation formulations. Thus, we compared the anti-SARS-CoV-2 activity of remdesivir and GS-441524 in Vero E6, Vero CCL-81, Calu-3, Caco-2 ​cells, and anti-HCoV-OC43 activity in Huh-7 ​cells. We also compared the cellular pharmacology of these two compounds in Vero E6, Vero CCL-81, Calu-3, Caco-2, Huh-7, 293T, BHK-21, 3T3 and human airway epithelial (HAE) cells. Overall, remdesivir exhibited greater potency and superior intracellular metabolism than GS-441524 except in Vero E6 and Vero CCL-81 ​cells.

Cathepsin A Mediates Ventricular Remote Remodeling and Atrial Cardiomyopathy in Rats With Ventricular Ischemia/Reperfusion

•

The role of the protease cathepsin A for the progression of left ventricular remote remodeling and atrial cardiomyopathy in ischemic cardiomyopathy is unknown.

•

In rats with ventricular ischemia and reperfusion, cathepsin A is up-regulated in the left ventricular and atrial tissue remote from the infarcted area.

•

Pharmacological inhibition of cathepsin A protease activity by SAR significantly reduces remote ventricular remodeling and atrial extracellular matrix remodeling, represented by fibrosis formation and connexin 43 lateralization.

•

Prevention of ventricular remote remodeling and atrial cardiomyopathy by SAR increased ventricular viable myocardium and atrial emptying function reducing susceptibility to atrial fibrillation.

•

Remote ventricular and atrial extracellular matrix remodeling may represent a promising target for pharmacological atrial fibrillation upstream therapy following myocardial infarction.

After myocardial infarction, remote ventricular remodeling and atrial cardiomyopathy progress despite successful revascularization. In a rat model of ventricular ischemia/reperfusion, pharmacological inhibition of the protease activity of cathepsin A initiated at the time point of reperfusion prevented extracellular matrix remodeling in the atrium and the ventricle remote from the infarcted area. This scenario was associated with preservation of more viable ventricular myocardium and the prevention of an arrhythmogenic and functional substrate for atrial fibrillation. Remote ventricular extracellular matrix remodeling and atrial cardiomyopathy may represent a promising target for pharmacological atrial fibrillation upstream therapy following myocardial infarction.