An Updated Review of Potential Drug Targets for Japanese Encephalitis

Japanese encephalitis virus (JEV), first identified in 1935, continues to be a major threat to human health, especially in the Asia-Pacific region, where it remains prevalent. JEV, a neurotropic flavivirus, spreads through Culex tritaeniorhynchus mosquito bites and causes severe brain infections with high morbidity and mortality rates. Despite the availability of vaccines, no licensed anti-JEV drugs exist. This review provides a comprehensive overview of the epidemiology, structural and nonstructural proteins, and pathogenesis of JEV and explores potential drug targets. This study highlights both conventional and nonconventional drug targets, with a focus on nonstructural JEV proteins, which may hold promise for therapeutic development. This review also discusses drug targets shared by JEV and other flaviviruses, such as dengue, Zika, and West Nile virus, which reveal common pathways for viral entry and replication, along with distinct mechanisms specific to JEV. Key receptor interactions, including DC-SIGN, TAM receptor, sialic acid, LDLR, and CLEC5A interactions, are involved in JEV transmission and immune evasion. Additionally, the NMDA receptor has been identified as a critical player in JEV pathogenesis, suggesting new opportunities for neuroprotective therapies. A major obstacle in JEV drug development is the blood-brain barrier (BBB), which hinders the delivery of therapeutic agents to the central nervous system (CNS). Recent research has emphasized the need for innovative drug delivery systems that can cross the BBB, reducing viral replication and neural damage. While clinical trials with traditional antivirals have yielded mixed results, live attenuated and inactivated vaccines have shown promise in preventing JEV infection. Additionally, nucleic acid-based therapies, including microRNAs and short hairpin RNAs (shRNAs), are emerging as potential treatments, with nanoparticle-based delivery systems offering solutions to overcome BBB challenges. This review underscores the need for an integrated approach, including improved vaccines, targeted drug delivery strategies, and novel therapeutics, to effectively combat JEV infections on a global scale.