Langsjoen Rose M, Auguste Albert J, Rossi Shannan L, Roundy Christopher M, Penate Heidy N, Kastis Maria, Schnizlein Matthew K, Le Kevin C, Haller Sherry L, Chen Rubing, Watowich Stanley J, Weaver Scott C
Institute for Translational Science, University of Texas Medical Branch, Galveston, TX, USA; Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX, USA.
Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX, USA; Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA.
Antiviral Res. 2017 Jul;143:246-251. doi: 10.1016/j.antiviral.2017.04.014. Epub 2017 Apr 28.
Alphaviruses require conserved cysteine residues for proper folding and assembly of the E1 and E2 envelope glycoproteins, and likely depend on host protein disulfide isomerase-family enzymes (PDI) to aid in facilitating disulfide bond formation and isomerization in these proteins. Here, we show that in human HEK293 cells, commercially available inhibitors of PDI or modulators thereof (thioredoxin reductase, TRX-R; endoplasmic reticulum oxidoreductin-1, ERO-1) inhibit the replication of CHIKV chikungunya virus (CHIKV) in vitro in a dose-dependent manner. Further, the TRX-R inhibitor auranofin inhibited Venezuelan equine encephalitis virus and the flavivirus Zika virus replication in vitro, while PDI inhibitor 16F16 reduced replication but demonstrated notable toxicity. 16F16 significantly altered the viral genome: plaque-forming unit (PFU) ratio of CHIKV in vitro without affecting relative intracellular viral RNA quantities and inhibited CHIKV E1-induced cell-cell fusion, suggesting that PDI inhibitors alter progeny virion infectivity through altered envelope function. Auranofin also increased the extracellular genome:PFU ratio but decreased the amount of intracellular CHIKV RNA, suggesting an alternative mechanism of action. Finally, auranofin reduced footpad swelling and viremia in the C57BL/6 murine model of CHIKV infection. Our results suggest that targeting oxidative folding pathways represents a potential new anti-alphavirus therapeutic strategy.
甲病毒需要保守的半胱氨酸残基来实现E1和E2包膜糖蛋白的正确折叠和组装，并且可能依赖宿主蛋白二硫键异构酶家族的酶（PDI）来促进这些蛋白中二硫键的形成和异构化。在此，我们表明，在人HEK293细胞中，市售的PDI抑制剂或其调节剂（硫氧还蛋白还原酶，TRX-R；内质网氧化还原酶-1，ERO-1）以剂量依赖的方式抑制基孔肯雅病毒（CHIKV）在体外的复制。此外，TRX-R抑制剂金诺芬在体外抑制委内瑞拉马脑炎病毒和黄病毒寨卡病毒的复制，而PDI抑制剂16F16降低了复制，但显示出明显的毒性。16F16显著改变了CHIKV在体外的病毒基因组：空斑形成单位（PFU）比例，而不影响细胞内病毒RNA的相对量，并抑制CHIKV E1诱导的细胞-细胞融合，这表明PDI抑制剂通过改变包膜功能来改变子代病毒体的感染性。金诺芬也增加了细胞外基因组：PFU比例，但减少了细胞内CHIKV RNA的量，提示了一种不同的作用机制。最后，金诺芬减轻了CHIKV感染的C57BL/6小鼠模型中的足垫肿胀和病毒血症。我们的结果表明，靶向氧化折叠途径代表了一种潜在的抗甲病毒新治疗策略。
