Anemoside B4 inhibits SARS-CoV-2 replication in vitro and in vivo

Mingyue Xiao; Ronghua Luo; Qinghua Liang; Honglv Jiang; Yanli Liu; Guoqiang Xu; Hongwei Gao; Yongtang Zheng; Qiongming Xu; Shilin Yang

doi:10.1016/j.chmed.2023.09.005

Anemoside B4 inhibits SARS-CoV-2 replication in vitro and in vivo

Chin Herb Med. 2023 Dec 13;16(1):106-112. doi: 10.1016/j.chmed.2023.09.005. eCollection 2024 Jan.

Authors

Mingyue Xiao¹, Ronghua Luo², Qinghua Liang¹, Honglv Jiang^{1

3}, Yanli Liu¹, Guoqiang Xu^{1

3}, Hongwei Gao⁴, Yongtang Zheng², Qiongming Xu¹, Shilin Yang¹

Affiliations

¹ College of Pharmaceutical Sciences, Soochow University, Suzhou 215123, China.
² Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences, KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China.
³ Jiangsu Key Laboratory of Neuropsychiatric Diseases and Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Soochow University, Suzhou 215123, China.
⁴ College of Pharmacy, Guangxi University of Chinese Medicine, Nanning 530000, China.

Abstract

Objective: Anemoside B4 (AB4), the most abundant triterpenoidal saponin isolated from Pulsatilla chinensis, inhibited influenza virus FM1 or Klebsiella pneumoniae-induced pneumonia. However, the anti-SARS-CoV-2 effect of AB4 has not been unraveled. Therefore, this study aimed to determine the antiviral activity and potential mechanism of AB4 in inhibiting human coronavirus SARS-CoV-2 in vivo and in vitro.

Methods: The cytotoxicity of AB4 was evaluated using the Cell Counting Kit-8 (CCK8) assay. SARS-CoV-2 infected HEK293T, HPAEpiC, and Vero E6 cells were used for in vitro assays. The antiviral effect of AB4 in vivo was evaluated by SARS-CoV-2-infected hACE2-IRES-luc transgenic mouse model. Furthermore, label-free quantitative proteomics and bioinformatic analysis were performed to explore the potential antiviral mechanism of action of AB4. Type I IFN signaling-associated proteins were assessed using Western blotting or immumohistochemical staining.

Results: The data showed that AB4 reduced the propagation of SARS-CoV-2 along with the decreased Nucleocapsid protein (N), Spike protein (S), and 3C-like protease (3CLpro) in HEK293T cells. In vivo antiviral activity data revealed that AB4 inhibited viral replication and relieved pneumonia in a SARS-CoV-2 infected mouse model. We further disclosed that the antiviral activity of AB4 was associated with the enhanced interferon (IFN)-β response via the activation of retinoic acid-inducible gene I (RIG-1) like receptor (RLP) pathways. Additionally, label-free quantitative proteomic analyses discovered that 17 proteins were significantly altered by AB4 in the SARS-CoV-2 coronavirus infections cells. These proteins mainly clustered in RNA metabolism.

Conclusion: Our results indicated that AB4 inhibited SARS-CoV-2 replication through the RLR pathways and moderated the RNA metabolism, suggesting that it would be a potential lead compound for the development of anti-SARS-CoV-2 drugs.

Keywords: RNA metabolism; SARS-CoV-2; anemoside B4; interferon; quantitative proteomics.