Screening of FDA-Approved Drugs for Inhibitors of Japanese Encephalitis Virus Infection

Abstract

Japanese encephalitis virus (JEV), an arthropod-borne flavivirus, is a major cause of acute viral encephalitis in humans. No approved drug is available for the specific treatment of JEV infections, and the available vaccines are not effective against all clinical JEV isolates. In the study described here, a high-throughput screening of an FDA-approved drug library for inhibitors of JEV was performed. Five hit drugs that inhibited JEV infection with a selective index of >10 were identified. The antiviral activities of these five hit drugs against other flavivirus, including Zika virus, were also validated. As three of the five hit drugs were calcium inhibitors, additional types of calcium inhibitors that confirmed that calcium is essential for JEV infection, most likely during viral replication, were utilized. Adaptive mutant analysis uncovered that replacement of Q130, located in transmembrane domain 3 of the nonstructural NS4B protein, which is relatively conserved in flaviviruses, with R or K conferred JEV resistance to manidipine, a voltage-gated Ca2+ channel (VGCC) inhibitor, without an apparent loss of the viral growth profile. Furthermore, manidipine was indicated to protect mice against JEV-induced lethality by decreasing the viral load in the brain, while it abrogated the histopathological changes associated with JEV infection. This study provides five antiflavivirus candidates and identifies cytoplasmic calcium to be a novel antiviral target for the treatment of JEV infection. The findings reported here provide therapeutic possibilities for combating infections caused by flaviviruses.IMPORTANCE No approved therapy for the treatment of Japanese encephalitis virus infection is currently available. Repurposing of approved drugs would accelerate the development of a therapeutic stratagem. In this study, we screened a library of FDA-approved drugs and identified five hit drugs, especially calcium inhibitors, exerting antiflavivirus activity that blocked viral replication. The in vivo efficacy and toxicity of manidipine were investigated with a mouse model of JEV infection, and the viral target was identified by generating an adaptive mutant.

Porcine deltacoronavirus (PDCoV) modulates calcium influx to favor viral replication

“…All three tested blockers reduced PDCoV yields significantly. Previous studies revealed that these blockers also exhibited inhibitory effects on the replication of the IAV, WNV, DENV and Japanese encephalitis virus (JEV) through different mechanisms (Dionicio et al, 2018;Fujioka et al, 2018;Scherbik and Brinton, 2010;Wang et al, 2017). The L-type calcium channel is a wellstudied calcium channel and the main route for calcium entry into cells (Kabir et al, 2016;Robin and Allard, 2015).…”

Screening of Natural Extracts for Inhibitors against Japanese Encephalitis Virus Infection

“…JEV infection-related clinical symptoms include fever, headache, vomiting, diarrhea, mental status changes, and signs of meningeal irritation (5); the ratio of survival with psychiatric sequelae or permanent neurological is approximately 44% (6). Although the morbidity and mortality decreased with the use of various vaccines, and several recent researchers have identified a number of compounds with anti-JEV activities, such as N-nonyl-deoxynojirimycin (7), dehydroepiandrosterone (8), N-methylisatin-beta-thiosemicarbazone derivative (SCH 16) (9), indirubin (10), manidipine (11), chlorpromazine (12), etanercept (13), and minocycline (14), few therapies beyond intensive supportive care to treat patients with JEV are available.…”

Drug Repurposing for Viral Infectious Diseases: How Far Are We?

“…This is the case for mycophenolic acid, niclosamide, nanchangmycin, cloroquine, and other antimalarial drugs. On the other hand, independent DR screenings against Japanese encephalitis virus (JEV), HCV, and dengue virus (DENV) led to the identification of antiviral activity of different FDA-approved drugs [25][26][27]. In particular, the dopamine D2 receptor antagonist prochlorperazine was identified as a potent inhibitor of HCV and DENV that acts by interfering with virus attachment and entry [26,28].…”