Dr. Neher's Biophysics Laboratory for Innovative Drug Discovery, State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Avenida Wai Long, Taipa, Macau, China.
Dr. Neher's Biophysics Laboratory for Innovative Drug Discovery, State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Avenida Wai Long, Taipa, Macau, China; Department of Pharmaceutics, Faculty of Pharmacy, University of Khartoum, Khartoum, Sudan.
Phytomedicine. 2021 Jul;87:153591. doi: 10.1016/j.phymed.2021.153591. Epub 2021 May 5.
The outbreak of coronavirus (SARS-CoV-2) disease caused more than 100,000,000 people get infected and over 2,200,000 people being killed worldwide. However, the current developed vaccines or drugs may be not effective in preventing the pandemic of COVID-19 due to the mutations of coronavirus and the severe side effects of the newly developed vaccines. Chinese herbal medicines and their active components play important antiviral activities. Corilagin exhibited antiviral effect on human immunodeficiency virus (HIV), hepatitis C virus (HCV) and Epstein-Barr virus (EBV). However, whether it blocks the interaction between SARS-CoV-2 RBD and hACE2 has not been elucidated.
To characterize an active compound, corilagin derived from Phyllanthus urinaria as potential SARS-CoV-2 entry inhibitors for its possible preventive application in daily anti-virus hygienic products.
Computational docking coupled with bio-layer interferometry, BLI were adopted to screen more than 1800 natural compounds for the identification of SARS-CoV-2 spike-RBD inhibitors. Corilagin was confirmed to have a strong binding affinity with SARS-CoV-2-RBD or human ACE2 (hACE2) protein by the BLI, ELISA and immunocytochemistry (ICC) assay. Furthermore, the inhibitory effect of viral infection of corilagin was assessed by in vitro pseudovirus system. Finally, the toxicity of corilagin was examined by using MTT assay and maximal tolerated dose (MTD) studies in C57BL/6 mice.
Corilagin preferentially binds to a pocket that contains residues Cys 336 to Phe 374 of spike-RBD with a relatively low binding energy of -9.4 kcal/mol. BLI assay further confirmed that corilagin exhibits a relatively strong binding affinity to SARS-CoV-2-RBD and hACE2 protein. In addition, corilagin dose-dependently blocks SARS-CoV-2-RBD binding and abolishes the infectious property of RBD-pseudotyped lentivirus in hACE2 overexpressing HEK293 cells, which mimicked the entry of SARS-CoV-2 virus in human host cells. Finally, in vivo studies revealed that up to 300 mg/kg/day of corilagin was safe in C57BL/6 mice. Our findings suggest that corilagin could be a safe and potential antiviral agent against the COVID-19 acting through the blockade of the fusion of SARS-CoV-2 spike-RBD to hACE2 receptors.
Corilagin could be considered as a safe and environmental friendly anti-SARS-CoV-2 agent for its potential preventive application in daily anti-virus hygienic products.
冠状病毒（SARS-CoV-2）疾病的爆发导致全球超过 1 亿人感染，超过 220 万人死亡。然而，由于冠状病毒的突变和新开发疫苗的严重副作用，目前开发的疫苗或药物可能无法有效预防 COVID-19 大流行。中草药及其活性成分具有重要的抗病毒活性。柯里拉京对人类免疫缺陷病毒（HIV）、丙型肝炎病毒（HCV）和 EBV 均有抗病毒作用。然而，它是否能阻断 SARS-CoV-2 RBD 与 hACE2 的相互作用尚未阐明。
从叶下珠中提取一种活性化合物柯里拉京，作为 SARS-CoV-2 进入抑制剂，用于日常抗病毒卫生产品的潜在预防应用。
采用计算对接与生物层干涉（BLI）相结合的方法，从 1800 多种天然化合物中筛选出 SARS-CoV-2 刺突-RBD 抑制剂。BLI、ELISA 和免疫细胞化学（ICC）实验证实柯里拉京与 SARS-CoV-2-RBD 或人 ACE2（hACE2）蛋白具有很强的结合亲和力。此外，通过体外假病毒系统评估柯里拉京对病毒感染的抑制作用。最后，采用 MTT 测定法和最大耐受剂量（MTD）研究在 C57BL/6 小鼠中检测柯里拉京的毒性。
柯里拉京优先与包含刺突-RBD 中 Cys 336 至 Phe 374 残基的口袋结合，结合能为-9.4 kcal/mol。BLI 实验进一步证实，柯里拉京与 SARS-CoV-2-RBD 和 hACE2 蛋白具有较强的结合亲和力。此外，柯里拉京呈剂量依赖性地阻断 SARS-CoV-2-RBD 结合，并消除 RBD 假型慢病毒在 hACE2 过表达 HEK293 细胞中的感染性，这模拟了 SARS-CoV-2 病毒进入人宿主细胞的过程。最后，体内研究表明，高达 300 mg/kg/天的柯里拉京在 C57BL/6 小鼠中是安全的。我们的研究结果表明，柯里拉京可能是一种安全且有潜力的抗 COVID-19 药物，通过阻断 SARS-CoV-2 刺突-RBD 与 hACE2 受体的融合发挥作用。
柯里拉京可作为一种安全的抗 SARS-CoV-2 药物，用于日常抗病毒卫生产品的潜在预防应用。
