Department of Medical Microbiology, Radboud University Nijmegen Medical Centre, Nijmegen Centre for Molecular Life Sciences, Nijmegen Institute for Infection, Inflammation and Immunity, Nijmegen, The Netherlands.
Antiviral Res. 2013 Aug;99(2):165-71. doi: 10.1016/j.antiviral.2013.05.011. Epub 2013 Jun 2.
Dengue virus (DENV) is an important human arthropod-borne virus with a major impact on public health. Nevertheless, a licensed vaccine or specific treatment is still lacking. We therefore screened the NIH Clinical Collection (NCC), a library of drug-like small molecules, for inhibitors of DENV replication using a cell line that contains a stably replicating DENV serotype 2 (DENV2) subgenomic replicon. The most potent DENV inhibitor in the NCC was δ opioid receptor antagonist SDM25N. This compound showed antiviral activity against wild-type DENV2 in both Hela and BHK-21 cells, but not in the C6/36 cell line derived from the mosquito Aedes albopictus. The structurally related compound naltrindole also inhibited DENV replication, albeit less potently. Using a transient subgenomic replicon, we demonstrate that SDM25N restricts genomic RNA replication rather than translation of the viral genome. We identified a single amino acid substitution (F164L) in the NS4B protein that confers resistance to SDM25N. Remarkably, an NS4B amino acid substitution (P104L), which was previously shown to confer resistance to the DENV inhibitor NITD-618, also provided resistance to SDM25N. In conclusion, we have identified a new DENV inhibitor, SDM25N, which restricts genomic RNA replication by - directly or indirectly - targeting the viral NS4B protein.
登革热病毒（DENV）是一种重要的人类虫媒病毒，对公共卫生有重大影响。然而，目前仍缺乏许可的疫苗或特效治疗药物。因此，我们使用含有稳定复制的 DENV 血清型 2（DENV2）亚基因组复制子的细胞系，从 NIH 临床收藏（NCC）药物样小分子文库中筛选 DENV 复制抑制剂。NCC 中最有效的 DENV 抑制剂是 δ 阿片受体拮抗剂 SDM25N。该化合物在 Hela 和 BHK-21 细胞中对野生型 DENV2 均表现出抗病毒活性，但在源自白纹伊蚊的 C6/36 细胞系中没有活性。结构相关的化合物纳曲吲哚也抑制 DENV 复制，但效力较弱。使用瞬时亚基因组复制子，我们证明 SDM25N 限制基因组 RNA 复制，而不是翻译病毒基因组。我们鉴定了 NS4B 蛋白中的单个氨基酸取代（F164L），该取代赋予了对 SDM25N 的抗性。值得注意的是，先前显示对 DENV 抑制剂 NITD-618 产生抗性的 NS4B 氨基酸取代（P104L）也赋予了对 SDM25N 的抗性。总之，我们已经鉴定出一种新的 DENV 抑制剂 SDM25N，它通过直接或间接靶向病毒 NS4B 蛋白来限制基因组 RNA 复制。
