Anti-SARS-CoV-2 activities in vitro of Shuanghuanglian preparations and bioactive ingredients
Anti-SARS-CoV-2 activities in vitro of Shuanghuanglian preparations and bioactive ingredients
复制标题
双黄连制剂及活性成分的体外抗SARS-CoV-2活性
DOI：
10.1038/s41401-020-0483-6
复制
发表时间：
2020-07-31
影响因子：
8.2
通讯作者：
Xu, Ye-chun
中科院分区：
文献类型：
--
作者：
Su, Hai-xia;Yao, Sheng;Xu, Ye-chun
人类感染严重急性呼吸综合征冠状病毒2型(SARS-CoV-2)导致冠状病毒病2019(新冠肺炎)，目前尚无治愈方法。3CL蛋白(3CL)是一种高度保守的蛋白水解酶，是冠状病毒复制所必需的，是开发广谱抗病毒药物的重要靶点。本研究考察了中国医学部治疗呼吸道感染的中成药双黄连制剂的抗SARS-CoV-2作用。双黄连口服液、注射用双黄连冻干粉及其活性成分均呈剂量依赖性抑制SARS-CoV-2 3CLPro及SARS-CoV-2在Vero E6细胞中的复制。双黄连的两个成分黄芩苷和黄芩素被鉴定为第一个非共价、非肽类的SARS-CoV-2 3CLPro抑制剂，并在细胞系统中显示出较强的抗病毒活性。值得注意的是，X射线蛋白质结晶学测定的黄芩素与SARS-CoV-2 3CLPro的结合方式与已知的3CLPro抑制剂的结合方式明显不同。黄芩素通过与两个催化残基-关键的S1/S2亚基和氧阴离子环相互作用，有效地固定在底物结合口袋的核心，起到催化二聚体前面的“屏障”的作用，有效地阻止底物进入活性中心内的催化二聚体。总之，本研究为探索中成药的体外药效，针对特定靶点有效地鉴定活性成分提供了范例，为双黄连口服液及两种新冠肺炎天然产物的体内研究提供了依据。
Human infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19) and there is no cure currently. The 3CL protease (3CLpro) is a highly conserved protease which is indispensable for CoVs replication, and is a promising target for development of broad-spectrum antiviral drugs. In this study we investigated the anti-SARS-CoV-2 potential of Shuanghuanglian preparation, a Chinese traditional patent medicine with a long history for treating respiratory tract infection in China. We showed that either the oral liquid of Shuanghuanglian, the lyophilized powder of Shuanghuanglian for injection or their bioactive components dose-dependently inhibited SARS-CoV-2 3CLpro as well as the replication of SARS-CoV-2 in Vero E6 cells. Baicalin and baicalein, two ingredients of Shuanghuanglian, were characterized as the first noncovalent, nonpeptidomimetic inhibitors of SARS-CoV-2 3CLpro and exhibited potent antiviral activities in a cell-based system. Remarkably, the binding mode of baicalein with SARS-CoV-2 3CLpro determined by X-ray protein crystallography was distinctly different from those of known 3CLpro inhibitors. Baicalein was productively ensconced in the core of the substrate-binding pocket by interacting with two catalytic residues, the crucial S1/S2 subsites and the oxyanion loop, acting as a "shield" in front of the catalytic dyad to effectively prevent substrate access to the catalytic dyad within the active site. Overall, this study provides an example for exploring the in vitro potency of Chinese traditional patent medicines and effectively identifying bioactive ingredients toward a specific target, and gains evidence supporting the in vivo studies of Shuanghuanglian oral liquid as well as two natural products for COVID-19 treatment.