PDF(Pubmed)
Abstract：
Zika virus (ZIKV) is a re-emerging mosquito-borne flavivirus that has been associated with congenital neurological defects in fetuses born to infected mothers. At present, no vaccine or antiviral therapy is available to combat this devastating disease. Repurposing drugs that target essential host factors exploited by viruses is an attractive therapeutic approach. Here, we screened a panel of clinically approved small-molecule kinase inhibitors for their antiviral effects against a clinical isolate of ZIKV and thoroughly characterized their mechanisms of action. We found that the Raf kinase inhibitors Dabrafenib and Regorafenib potently impair the replication of ZIKV, but not that of its close relative dengue virus. Time-of-addition experiments showed that both inhibitors target ZIKV infection at post-entry steps. We found that Dabrafenib, but not Regorafenib, interfered with ZIKV genome replication by impairing both negative- and positive-strand RNA synthesis. Regorafenib, on the other hand, altered steady-state viral protein levels, viral egress, and blocked NS1 secretion. We also observed Regorafenib-induced ER fragmentation in ZIKV-infected cells, which might contribute to its antiviral effects. Because these inhibitors target different steps of the ZIKV infection cycle, their use in combination therapy may amplify their antiviral effects which could be further explored for future therapeutic strategies against ZIKV and possibly other flaviviruses.
OBJECTIVE: There is an urgent need to develop effective therapeutics against re-emerging arboviruses associated with neurological disorders like Zika virus (ZIKV). We identified two FDA-approved kinase inhibitors, Dabrafenib and Regorafenib, as potent inhibitors of contemporary ZIKV strains at distinct stages of infection despite overlapping host targets. Both inhibitors reduced viral titers by ~1 to 2 log10 (~10-fold to 100-fold) with minimal cytotoxicity. Furthermore, we show that Dabrafenib inhibits ZIKV RNA replication whereas Regorafenib inhibits ZIKV translation and egress. Regorafenib has the added benefit of limiting NS1 secretion, which contributes to the pathogenesis and disease progression of several flaviviruses. Because these inhibitors affect distinct post-entry steps of ZIKV infection, their therapeutic potential may be amplified by combination therapy and likely does not require prophylactic administration. This study provides further insight into ZIKV-host interactions and has implications for the development of novel antivirals against ZIKV and possibly other flaviviruses.
OBJECTIVE: There is an urgent need to develop effective therapeutics against re-emerging arboviruses associated with neurological disorders like Zika virus (ZIKV). We identified two FDA-approved kinase inhibitors, Dabrafenib and Regorafenib, as potent inhibitors of contemporary ZIKV strains at distinct stages of infection despite overlapping host targets. Both inhibitors reduced viral titers by ~1 to 2 log10 (~10-fold to 100-fold) with minimal cytotoxicity. Furthermore, we show that Dabrafenib inhibits ZIKV RNA replication whereas Regorafenib inhibits ZIKV translation and egress. Regorafenib has the added benefit of limiting NS1 secretion, which contributes to the pathogenesis and disease progression of several flaviviruses. Because these inhibitors affect distinct post-entry steps of ZIKV infection, their therapeutic potential may be amplified by combination therapy and likely does not require prophylactic administration. This study provides further insight into ZIKV-host interactions and has implications for the development of novel antivirals against ZIKV and possibly other flaviviruses.
摘要：
寨卡病毒（ZIKV）是一种重新出现的蚊媒黄病毒，与受感染母亲所生的胎儿的先天性神经系统缺陷有关。目前,没有疫苗或抗病毒治疗可以对抗这种毁灭性的疾病。重新利用靶向病毒利用的必需宿主因子的药物是一种有吸引力的治疗方法。这里,我们筛选了一组临床批准的小分子激酶抑制剂对ZIKV临床分离株的抗病毒作用,并彻底表征了它们的作用机制.我们发现Raf激酶抑制剂Dabrafenib和Regorafenib可有效损害ZIKV的复制，但不是它的近亲登革热病毒。添加时间实验表明,两种抑制剂在进入后步骤都靶向ZIKV感染。我们发现Dabrafenib,但不是雷戈拉非尼,通过损害负链和正链RNA合成来干扰ZIKV基因组复制。Regorafenib,另一方面,改变稳态病毒蛋白水平，病毒的出口，并阻断NS1分泌。我们还在ZIKV感染的细胞中观察到Regorafenib诱导的ER片段化，这可能有助于其抗病毒作用。因为这些抑制剂针对ZIKV感染周期的不同步骤，它们在联合治疗中的使用可能会增强其抗病毒作用,这可以进一步探索未来针对ZIKV和可能的其他黄病毒的治疗策略.
目的：迫切需要开发针对与Zika病毒（ZIKV）等神经系统疾病相关的重新出现的虫媒病毒的有效疗法。我们确定了两种FDA批准的激酶抑制剂，Dabrafenib和Regorafenib,尽管宿主靶标重叠，但在感染的不同阶段作为当代ZIKV菌株的有效抑制剂。两种抑制剂均以最小的细胞毒性将病毒滴度降低〜1至2log10（〜10倍至100倍）。此外，我们显示Dabrafenib抑制ZIKVRNA复制，而Regorafenib抑制ZIKV翻译和外传。Regorafenib有限制NS1分泌的额外好处，这有助于几种黄病毒的发病机制和疾病进展。因为这些抑制剂会影响ZIKV感染的不同进入后步骤，它们的治疗潜力可以通过联合治疗得到放大,并且可能不需要预防性给药.这项研究提供了对ZIKV与宿主相互作用的进一步见解，并对开发针对ZIKV和可能的其他黄病毒的新型抗病毒药物具有意义。
目的：迫切需要开发针对与Zika病毒（ZIKV）等神经系统疾病相关的重新出现的虫媒病毒的有效疗法。我们确定了两种FDA批准的激酶抑制剂，Dabrafenib和Regorafenib,尽管宿主靶标重叠，但在感染的不同阶段作为当代ZIKV菌株的有效抑制剂。两种抑制剂均以最小的细胞毒性将病毒滴度降低〜1至2log10（〜10倍至100倍）。此外，我们显示Dabrafenib抑制ZIKVRNA复制，而Regorafenib抑制ZIKV翻译和外传。Regorafenib有限制NS1分泌的额外好处，这有助于几种黄病毒的发病机制和疾病进展。因为这些抑制剂会影响ZIKV感染的不同进入后步骤，它们的治疗潜力可以通过联合治疗得到放大,并且可能不需要预防性给药.这项研究提供了对ZIKV与宿主相互作用的进一步见解，并对开发针对ZIKV和可能的其他黄病毒的新型抗病毒药物具有意义。
