Epigallocatechin-3-Gallate, the Main Polyphenol in Green Tea, Inhibits Porcine Epidemic Diarrhea Virus In Vitro

Changchao Huan; Weiyin Xu; Bo Ni; Tingting Guo; Haochun Pan; Luyao Jiang; Lin Li; Jingting Yao; Song Gao

doi:10.3389/fphar.2021.628526

Epigallocatechin-3-Gallate, the Main Polyphenol in Green Tea, Inhibits Porcine Epidemic Diarrhea Virus In Vitro

Front Pharmacol. 2021 Feb 22:12:628526. doi: 10.3389/fphar.2021.628526. eCollection 2021.

Authors

Changchao Huan^{1

2

3}, Weiyin Xu^{1

2

3}, Bo Ni⁴, Tingting Guo⁵, Haochun Pan^{1

2

3}, Luyao Jiang^{1

2

3}, Lin Li^{1

2

3}, Jingting Yao^{1

2

3}, Song Gao^{1

2

3}

Affiliations

¹ Institutes of Agricultural Science and Technology Development, College of Veterinary Medicine, Yangzhou University, Yangzhou, China.
² Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China.
³ Key Laboratory of Avian Bioproduct Development, Ministry of Agriculture and Rural Affairs, Yangzhou, China.
⁴ China Animal Health And Epidemiology Center, Qingdao, China.
⁵ College of Medicine, Yangzhou University, Yangzhou, China.

Abstract

There are currently no licensed drugs against porcine epidemic diarrhea virus (PEDV), but vaccines are available. We identified a natural molecule, epigallocatechin-3-gallate (EGCG), the main polyphenol in green tea, which is effective against infection with PEDV. We used a variety of methods to test its effects on PEDV in Vero cells. Our experiments show that EGCG can effectively inhibit PEDV infections (with HLJBY and CV777 strains) at different time points in the infection using western blot analysis. We found that EGCG inhibited PEDV infection in a dose-dependent manner 24 h after the infection commenced using western blotting, plaque formation assays, immunofluorescence assays (IFAs), and quantitative reverse-transcriptase PCR (qRT-PCR). We discovered that EGCG treatment of Vero cells decreased PEDV attachment and entry into them by the same method analysis. Western blotting also showed that PEDV replication was inhibited by EGCG treatment. Whereas EGCG treatment was found to inhibit PEDV assembly, it had no effect on PEDV release. In summary, EGCG acts against PEDV infection by inhibiting PEDV attachment, entry, replication, and assembly.

Keywords: drug; epigallocatechin-3-gallate; green tea polyphenol; porcine epidemic diarrhea virus; virus inhibition.