Japanese encephalitis virus promotes its replication in neuronal cells by enhancing glycolysis via hypoxia-inducible factor-1α.

Japanese encephalitis virus (JEV), a causative agent of viral encephalitis, manipulates host metabolic pathways to support its replication in the host cells. Glycolysis is one of the crucial metabolic pathways regulated by most of the RNA viruses. In the current study, we investigated the regulation of glycolysis by JEV in Neuro-2a cells. JEV replication induces a time-dependent increase in glycolysis, demonstrated by decreased glucose and elevated lactic acid levels in the supernatant of infected cells. Furthermore, treatment with glycolytic inhibitors, such as 2-Deoxy-D-glucose and sodium oxamate, reduced virus replication. Moreover, supplementation with sodium pyruvate, an alternate energy source, and treatment with insulin promoted JEV replication, highlighting their positive role during metabolic stress in JEV-infected cells. JEV replication also enhanced the expression of several glycolytic enzymes. We identified hypoxia-inducible factor-1α (HIF-1α) as a critical regulator of glycolysis during JEV infection. JEV infection resulted in HIF-1α upregulation, indicating its role in replication kinetics. Cobalt chloride-induced stabilization of HIF-1α enhanced JEV replication, while its knockdown abrogated this effect in treated cells. Altogether, our results reveal that JEV modulates host glucose metabolism via HIF-1α to facilitate its replication and also highlight glycolytic inhibitors as potential antiviral against JEV.