Antiviral and neuroprotective activity of diallyl disulfide in Japanese encephalitis virus-challenged SH-SY5Y cells: a post-treatment approach for greater specificity.

Japanese encephalitis (JE) is the most common viral encephalitis caused by the Japanese encephalitis virus (JEV), primarily affecting children. Currently, there is no approved and effective antiviral drug against JEV infection. Diallyl disulfide (DADS) exerts antiviral activity against dengue virus, one of the Flavivirus. To establish the antiviral and neuroprotective potential of DADS against JEV. The present study explored the neuroprotective and antiviral activities of DADS in JEV-challenged SH-SY5Y cells in pre-, post-, and co-treatment approaches. Further, the study also investigated the nature of interaction between DADS and four drug targets of JEV such as envelope protein, NS3 helicase, NS3 protease, and NS5 RdRp using virtual screening. In plaque yield reduction assay, DADS significantly reduced plaque titer by 59.8% in post-treatment with median inhibitory concentrations of 165.8 µM. A similar antiviral effect was observed in an immunocytochemistry assay in post-infection treatment mode. The in vitro antiviral activity of DADS was further supported by its robust binding affinity for NS3 Helicase and RNA-dependent RNA polymerase, highlighting DADS as a multi-target therapeutic agent. Significant neuroprotective activity was also observed in post-treatment methods, with cell viability of 75.87%, 79.15%, and 85.05% at 50, 100, and 200 µM concentrations, respectively. The observed neuroprotective activities of the drug may be attributed to its antioxidant and anti-apoptotic activity in JEV-challenged cells. The network pharmacology analysis revealed key hub genes, including PTGS2, MAPK3, CCR2, MAOs, and DRD2, which may serve as drug targets for DADS to modulate JEV-induced immune dysregulation and neuroinflammation. This study has provided insight into the antiviral and neuroprotective potential of DADS against JEV. However, further in vivo and clinical studies are warranted to develop the drug as a therapeutic agent for the management of JE.