title: The viral polymerase inhibitor 2'-C-methylcytidine inhibits Norwalk virus replication and protects against norovirus-induced diarrhea and mortality in a mouse model.
abstract: Human noroviruses are a major cause of food-borne illness, accountable for 50% of all-etiologies outbreaks of acute gastroenteritis (in both developing and developed countries). There is no vaccine or antiviral drug for the prophylaxis or treatment of norovirus-induced gastroenteritis. We recently reported the inhibitory effect of 2'-C-methylcytidine (2CMC), a hepatitis C virus polymerase inhibitor, on the in vitro replication of murine norovirus (MNV). Here we evaluated the inhibitory effect of 2CMC on in vitro human norovirus replication through a Norwalk virus replicon model and in a mouse model by using AG129 mice orally infected with MNV. Survival, weight, and fecal consistency were monitored, and viral loads in stool samples and organs were quantified. Intestines were examined histologically. 2CMC reduced Norwalk virus replicon replication in a dose-dependent manner and was able to clear cells of the replicon. Treatment of MNV-infected AG129 mice with 2CMC (i) prevented norovirus-induced diarrhea; (ii) markedly delayed the appearance of viral RNA and reduced viral RNA titers in the intestine, mesenteric lymph nodes, spleen, lungs, and stool; (iii) completely prevented virus-induced mortality; and (iv) resulted in protective immunity against a rechallenge. We demonstrate for the first time that a small-molecule inhibitor of norovirus replication protects from virus-induced disease and mortality in a relevant animal model. These findings pave the way for the development of potent and safe antivirals as prophylaxis and therapy of norovirus infection.
authors.affiliation: Laboratório de Microbiologia, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal.
authors.forename: Joana
authors.initials: J
authors.lastname: Rocha-Pereira
authors.forename: Dirk
authors.initials: D
authors.lastname: Jochmans
authors.forename: Yannick
authors.initials: Y
authors.lastname: Debing
authors.forename: Erik
authors.initials: E
authors.lastname: Verbeken
authors.forename: Maria S J
authors.initials: MS
authors.lastname: Nascimento
authors.forename: Johan
authors.initials: J
authors.lastname: Neyts
mesh_terms: D000825:Animal Structures / Q000821:virology; D000818:Animals; D000998:Antiviral Agents / Q000494:pharmacology / Q000627:therapeutic use*; D001835:Body Weight; D017250:Caliciviridae Infections / Q000401:mortality / Q000473:pathology / Q000517:prevention & control*; D003562:Cytidine / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D003967:Diarrhea / Q000401:mortality / Q000473:pathology / Q000517:prevention & control*; D004195:Disease Models, Animal; D005243:Feces / Q000821:virology; D005260:Female; D008297:Male; D051379:Mice; D029322:Norovirus / Q000187:drug effects*; D009663:Norwalk virus / Q000187:drug effects* / Q000502:physiology; D012367:RNA, Viral / Q000302:isolation & purification; D016019:Survival Analysis; D019562:Viral Load; D014779:Virus Replication / Q000187:drug effects*
chemical_list: D000998:Antiviral Agents; D012367:RNA, Viral; C513402:2'-C-methylcytidine; D003562:Cytidine