Green Tea Polyphenol Epigallocatechin-3-gallate–Alleviated Coxsackievirus B3–induced Myocarditis Through Inhibiting Viral Replication but Not Through Inhibiting Inflammatory Responses

Viral myocarditis, which is mainly caused by coxsackievirus B3 (CVB3), affects about 5%-20% of the world population and still lacks efficient treatments. Green tea, a tonic and healthful beverage that was originated in ancient China, has been receiving considerable attention for its protective effect on cardiovascular diseases in recent years. In the present investigation, we aimed to explore the effect of green tea polyphenol epigallocatechin-3-gallate (EGCG) on CVB3-induced myocarditis and its underlying mechanism. Our study showed that EGCG could alleviate CVB3-induced myocarditis as evidenced by less cardiac injury and higher survival rate. Furthermore, we found that EGCG failed to downregulate the expression of inflammatory cytokines but could significantly inhibit the replication of CVB3. Furthermore, we found that EGCG treatment could downregulate the protein expression level of coxsackievirus and adenovirus receptor, the major receptor for CVB3 to infect cardiac myocytes. In conclusion, our data indicated that EGCG could ameliorate CVB3-induced myocarditis through inhibiting viral replication, which might provide a potential novel therapeutic strategy for viral myocarditis.