State Key Laboratory of Organ Failure Research, Guangdong Provincial Key Laboratory of New Drug Screening, Guangzhou Key Laboratory of Drug Research for Emerging Virus Prevention and Treatment, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, 510515, PR China.
State Key Laboratory of Organ Failure Research, Guangdong Provincial Key Laboratory of New Drug Screening, Guangzhou Key Laboratory of Drug Research for Emerging Virus Prevention and Treatment, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, 510515, PR China.
J Pharmacol Sci. 2018 Dec;138(4):247-256. doi: 10.1016/j.jphs.2018.06.012. Epub 2018 Jun 25.
Dengue virus (DENV) annually infects 400 million people worldwide. Unfortunately, there is lack of widely protective vaccine or drugs against DENV. The viral RNA-dependent RNA polymerase (RdRp) of NS5 protein is highly conserved among different DENV subtypes, thus presenting itself as an attractive target for drug design. In the current research, SPRi was performed to screen compounds against DENV2 RdRp and 5(1H)-Quinazolinone,2-(4-bromophenyl)-2,3,4,6,7,8-hexahydro-7,7-dimethyl-1,3-diphenyl (Q63) was successfully screened out with a KD of 0.9 μM. Then, ITC and molecular docking assay was performed to access the binding mechanism between Q63 and DENV2 RdRp. Meanwhile, Q63 also decreased the intermediate dsRNA production, which was the product of RdRp. Further the antiviral effects of Q63 were evaluated on mosquito C6/36 cells and mammalian BHK-21 cells. Q63 reduced CPE and cell toxicity effect after DENV2 infection on C6/36 and BHK-21 cells, with an EC of 2.08 μM. Time of addition assay revealed that Q63 affected the early genome RNA replication stage, including genome RNA replication. In addition, Q63 down-regulated STAT1 phosphorylation, ISG15 and ISG54 after DENV2 infection. In summary, Q63 was found to be a novel RdRp non-nucleoside inhibitor and a potential lead compound for coping with DENV infectious disease in the future.
登革热病毒（DENV）每年在全球感染 4 亿人。不幸的是，目前缺乏针对 DENV 的广泛保护疫苗或药物。NS5 蛋白的病毒 RNA 依赖性 RNA 聚合酶（RdRp）在不同的 DENV 亚型之间高度保守，因此它是药物设计的一个有吸引力的靶点。在目前的研究中，SPRi 被用于筛选针对 DENV2 RdRp 的化合物，成功筛选出 5(1H)-喹唑啉酮，2-(4-溴苯基)-2,3,4,6,7,8-六氢-7,7-二甲基-1,3-二苯基（Q63），其 KD 值为 0.9 μM。然后，进行了 ITC 和分子对接实验，以研究 Q63 与 DENV2 RdRp 之间的结合机制。同时，Q63 还减少了 RdRp 的中间 dsRNA 产物的产生。进一步评估了 Q63 在蚊子 C6/36 细胞和哺乳动物 BHK-21 细胞上的抗病毒作用。Q63 降低了 DENV2 感染后 C6/36 和 BHK-21 细胞的 CPE 和细胞毒性作用，EC 值为 2.08 μM。时效实验表明，Q63 影响早期基因组 RNA 复制阶段，包括基因组 RNA 复制。此外，Q63 下调了 DENV2 感染后 STAT1 磷酸化、ISG15 和 ISG54。总之，发现 Q63 是一种新型的 RdRp 非核苷抑制剂，是未来应对 DENV 传染病的潜在先导化合物。
