Insight into cytotoxic and molecular mechanisms of bee venom and its nanoemulsion against West Nile virus in vitro.

West Nile virus (WNV) causes West Nile fever and is primarily transmitted by Culex spp. mosquitoes. The primary hosts of WNV are birds, while humans and horses can also develop illness following infection. Currently, no specific antiviral therapy exists for WNV, and vaccination remains the only effective preventive measure. This study aimed to evaluate the efficiency of the crude bee venom (BV) and its nanoemulsion (NE) on WNV by determining in vitro Vero cells cytotoxicity and viral titer by RT-qPCR. We also conducted BV peptides-envelope glycoprotein of WNV interactions by molecular docking analysis. The NE of BV was characterized by dynamic light scattering (DLS) and zeta potential analyses. The DLS revealed that the size of NE was greater than that of BV. Also, the DLS showed that the polydispersity index of NE was less than that of BV (0.349 and 0.557, respectively). Zeta potential analysis of NE was slightly less than that of BV (23.0 and 23.7 mV, respectively). Both treatments showed low cytopathic effects on Vero cells compared to positive control infected with WNV. RT-qPCR revealed that the titer of WNV was lower in cells treated with BV and its NE than in controls. Molecular docking revealed BV peptides-envelope glycoprotein of WNV interactions, with binding energy of - 5.2, - 4.5, - 13.0, - 10.8, and - 5.1 kcal/mol for the peptides apamin, tertiapin, melittin, mast cell degranulating peptide, and secapin-2 peptide, respectively. BV-NE demonstrated preliminary in vitro anti-WNV activity requiring mechanistic, toxicological, and in vivo validation.