The modulation of metabolomics and antioxidant stress is involved in the effect of nitazoxanide against influenza A virus in vitro

The prevalence of highly infectious influenza A virus (IAV) is still a major threat to global human health. Nitazoxanide (NTZ) possesses potent antiviral properties against the influenza virus. However, the role of small molecular metabolites and antioxidant stress in the NTZ’s anti-influenza virus mechanism is not yet fully understood. This study compared the changes in cellular metabolism, ROS levels, antioxidant enzyme activities, and Keap-1/Nrf2 pathway in IAV-infected MDCK cells after NTZ treatment in vitro, using LC-MS-based metabolomics, flow cytometry, immunoblot. We observed that the NTZ treatment in the IAV-infected cells drastically altered the metabolism of small molecules, among which eleven metabolites were highly relevant to NTZ. The virus induced oxidative stress was also remarkably suppressed by NTZ. Meanwhile, the Nrf2 pathway and some proteins with modulating antiviral activity were activated after NTZ treatment, protecting cells from IAV injury. Therefore, regulation of the intracellular oxidative state is the primary outcome of NTZ treatment, which may underpin an antiviral mechanism attributed to the thiazolide.