MilliporeSigma
  • Inhibitors of dihydroorotate dehydrogenase cooperate with molnupiravir and N4-hydroxycytidine to suppress SARS-CoV-2 replication.

Inhibitors of dihydroorotate dehydrogenase cooperate with molnupiravir and N4-hydroxycytidine to suppress SARS-CoV-2 replication.

iScience (2022-05-03)
Kim M Stegmann, Antje Dickmanns, Natalie Heinen, Claudia Blaurock, Tim Karrasch, Angele Breithaupt, Robert Klopfleisch, Nadja Uhlig, Valentina Eberlein, Leila Issmail, Simon T Herrmann, Amelie Schreieck, Evelyn Peelen, Hella Kohlhof, Balal Sadeghi, Alexander Riek, John R Speakman, Uwe Groß, Dirk Görlich, Daniel Vitt, Thorsten Müller, Thomas Grunwald, Stephanie Pfaender, Anne Balkema-Buschmann, Matthias Dobbelstein
ABSTRACT

The nucleoside analog N4-hydroxycytidine (NHC) is the active metabolite of the prodrug molnupiravir, which has been approved for the treatment of COVID-19. SARS-CoV-2 incorporates NHC into its RNA, resulting in defective virus genomes. Likewise, inhibitors of dihydroorotate dehydrogenase (DHODH) reduce virus yield upon infection, by suppressing the cellular synthesis of pyrimidines. Here, we show that NHC and DHODH inhibitors strongly synergize in the inhibition of SARS-CoV-2 replication in vitro. We propose that the lack of available pyrimidine nucleotides upon DHODH inhibition increases the incorporation of NHC into nascent viral RNA. This concept is supported by the rescue of virus replication upon addition of pyrimidine nucleosides to the media. DHODH inhibitors increased the antiviral efficiency of molnupiravir not only in organoids of human lung, but also in Syrian Gold hamsters and in K18-hACE2 mice. Combining molnupiravir with DHODH inhibitors may thus improve available therapy options for COVID-19.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Anti-dsRNA Antibody, clone rJ2, culture supernatant, clone rJ2, from mouse