Scientists from the Department of Microbiology, University of Hong Kong (HKU) recently discovered a compound with broad antiviral activity against viruses causing Middle East Respiratory Syndrome (MERS), avian flu (H7N9), severe acute respiratory syndrome (SARS) and Zika fever.

The compound, called AM580, is a synthetic retinoid acid receptor-alpha (RAR-α) agonist that interferes with viruses’ lipid metabolism through interaction with sterol regulatory element binding proteins (SREBP). [Nat Commun 2019, doi: 10.1038/s41467-018-08015-x]

“Profound increases in major lipogenic enzymes are associated with viral infections and AM580 was shown to antagonize these changes, thereby reducing virus replication,” the investigators explained.

In vitro experiments showed that treatment with AM580 reduced MERS viral titres in cell culture supernatants and decreased expression of viral nucleoproteins. AM580’s antiviral effect was also observed in other important viruses causing epidemics, such as SARS, H1N1 and Zika viruses. 

In vivo experiments in MERS-infected mice treated with AM580 showed less body weight loss (p<0.05) and lower lung tissue virus titres and viral loads (p<0.01) vs control mice.

Moreover, mice challenged with H7N9 (avian flu) viruses then treated with AM580 had higher survival rates (60 percent vs 0 percent; p<0.01) and lower viral loads in lung tissues (p<0.01) vs control mice.