寨卡病毒(ZIKV)是一种蚊子传播的黄病毒,会导致严重的神经系统疾病,例如胎儿的小头症。最近,ZIKV于2015年在巴西爆发。迄今为止,在临床上没有批准治疗ZIKV感染的治疗剂。这里,我们筛选了一种能抑制ZIKV非结构蛋白2B(NS2B)-NS3蛋白酶(ZIKVNS2B-NS3蛋白酶)功能的小分子抑制剂,从而干扰病毒复制和传播。首先,我们确定了化合物3的半数最大抑制浓度(IC50)(14.01μM),8(6.85μM),和9(14.2μM),并证实它们都是非竞争性抑制剂。此外,我们已经使用盲分子对接方法来模拟ZIKVNS2B-NS3蛋白酶对三种非竞争性抑制剂(化合物3、8和9)的抑制区域。结果表明,四个变构结合残基(Gln139,Trp148,Leu150和Val220)可以与三种化合物形成氢键或非键合相互作用。这种相互作用可能会导致NS2B-NS3蛋白酶的反应中心构象变化,从而降低催化效率。将细胞活力降低50%所需的化合物浓度(CC50),和抑制病毒诱导的细胞病变效应50%(EC50)的三种潜在化合物所需的化合物浓度>200μM,2.15μM(化合物3),>200μM,0.52μM(化合物8)和61.48μM,3.52μM(化合物9),替莫芬为61.05μM,2μM,分别。为进一步的动物实验选择候选化合物,我们分析了化合物3(93.02)的选择性指数(SI),8(384.61),9(17.46),和替莫芬(30.53,FDA批准的抗癌药物)。化合物8具有最高的SI值。因此,在动物模型中选择化合物8进行验证。在体内,在ZIKV感染的乳鼠模型中,化合物8显着延迟ZIKV诱导的致死性和疾病症状,并减少ZIKV诱导的体重减轻。我们得出结论,化合物8作为抗ZIKV感染的潜在未来治疗剂值得进一步研究。
Zika virus (ZIKV) is a mosquito-borne flavivirus that causes severe neurological disorders, such as microcephaly in fetuses. Most recently, an outbreak of ZIKV started in Brazil in 2015. To date, no therapeutic agents have been approved to treat ZIKV infection in the clinic. Here, we screened a small molecule inhibitor that can inhibit the function of ZIKV non-structural protein 2B (NS2B)-NS3 protease (ZIKV NS2B-NS3 protease), thereby interfering with viral replication and spread. First, we identified the half maximal inhibitory concentration (IC50) of compound 3 (14.01 μM), 8 (6.85 μM), and 9 (14.2 μM) and confirmed that they are all non-competitive inhibitors. In addition, we have used the blind molecular docking method to simulate the inhibition area of three non-competitive inhibitors (compound 3, 8, and 9) with the ZIKV NS2B-NS3 protease. The results indicated that the four allosteric binding residues (Gln139, Trp148, Leu150, and Val220) could form hydrogen bonds or non-bonding interactions most frequently with the three compounds. The interaction might induce the reaction center conformation change of NS2B-NS3 protease to reduce catalyzed efficiency. The concentration of compounds required to reduce cell viability by 50% (CC50), and the concentration of compounds required to inhibit virus-induced cytopathic effect by 50% (EC50) of three potential compounds are >200 μM, 2.15 μM (compound 3), > 200 μM, 0.52 μM (compound 8) and 61.48 μM, 3.52 μM (compound 9), and Temoporfin are 61.05 μM, 2 μM, respectively. To select candidate compounds for further animal experiments, we analyzed the selectivity index (SI) of compound 3 (93.02), 8 (384.61), 9 (17.46), and Temoporfin (30.53, FDA-approved drug against cancer). Compound 8 has the highest SI value. Therefore, compound 8 was selected for verification in animal models. In vivo, compound 8 significantly delayed ZIKV-induced lethality and illness symptoms and decreased ZIKV-induced weight loss in a ZIKV-infected suckling mouse model. We conclude that compound 8 is worth further investigation for use as a potential future therapeutic agent against ZIKV infection.