The modulation of proteomics and antioxidant stress is involved in the effect of nitazoxanide against Japanese encephalitis virus in vitro.

Japanese encephalitis virus (JEV) is a significant circulating arbovirus flavivirus and the primary cause of viral encephalitis in Asia. Previous studies have demonstrated that nitazoxanide (NTZ), an antiparasitic gastroenteritis medication classified as a thiazolide, exhibits efficacy against JEV both in vitro and in vivo. To explore the potential antiviral mechanisms, we employed Tandem Mass Tag (TMT)-based quantitative proteomics to identify differentially expressed proteins (DEPs) among three groups: Blank cell group, JEV-infected cell group, and JEV-infected cells treated with NTZ. Our analysis revealed that NTZ treatment led to the upregulation of 30 DEPs and downregulation of 54 DEPs in JEV-infected cells. Enrichment analysis using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) indicated that these DEPs are involved in various biological processes and signaling pathways, including transport, localization, response to wounding, P53 pathway activation, and fatty acid metabolism-related pathways. Moreover, we observed that the expression trend of TMX2, a protein associated with redox homeostasis, was consistent with findings from TMT-based quantitative proteomics. Further investigations into reactive oxygen species (ROS), mitochondrial membrane potential, antioxidant enzyme activity, and the KEAP1-NRF2 pathway demonstrated that NTZ effectively regulates the KEAP1-NRF2 pathway while suppressing oxidative stress induced by JEV infection. In conclusion, the proteomic data along with antioxidant stress results presented herein provide a foundational basis for further research into the molecular mechanisms and potential targets of NTZ against JEV.