Guangxi Key Laboratory of Aquatic Biotechnology and Modern Ecological Aquaculture, Guangxi Engineering Research Center for Fishery Major Diseases Control and Efficient Healthy Breeding Industrial Technology (GERCFT), Guangxi Academy of Sciences, Nanning 530000, China.
China-ASEAN Modern Fishery Industry Technology Transfer Demonstration Center, Nanning 530000, China.
Viruses. 2023 Jan 3;15(1):151. doi: 10.3390/v15010151.
(1) Background: Largemouth bass virus (LMBV) is a major viral pathogen in largemouth bass () aquaculture that often causes high mortality and heavy economic losses, thus developing treatments to combat this pathogen is of great commercial importance. Green tea is a well-known medicinal plant that contains active ingredients with antiviral, antibacterial, and other biological activities. The goals of this study were to explore the effect and mechanism of green tea source compounds on LMBV and provide data to serve as the basis for the screening of targeted drugs in the future. In this study, we evaluated the effects of the main component of green tea, epigallocatechin-3-gallate (EGCG), against LMBV infection. (2) Methods: The safe working concentration of EGCG was identified by cell viability detection and light microscopy. The antiviral activity and mechanism of action of EGCG against LMBV infection were evaluated with light microscopy, an aptamer 6-carboxy-fluorescein-based fluorescent molecular probe, and reverse transcription quantitative PCR. (3) Results: The safe working concentration of EGCG was ≤10 μg/mL. EGCG showed significant anti-LMBV infection activity in a concentration-dependent manner, and it also destroyed the structure of virus particles. EGCG impacted the binding of virus particles to cell receptors and virus invasion into the host cells. Inhibitory effects of EGCG on LMBV particles, LMBV binding to the host-cell membrane, and LMBV invasion were 84.89%, 98.99%, and 95.23%, respectively. Meanwhile, the effects of EGCG subsequently were verified in vivo. The fatality rate of the LMBV + EGCG group was significantly lower than that of the LMBV group. (4) Conclusions: Our results suggest that EGCG has effective antiviral properties against LMBV and may be a candidate for the effective treatment and control of LMBV infections in largemouth bass aquaculture.
(1) 背景：大口黑鲈病毒（LMBV）是大口黑鲈养殖业中的一种主要病毒病原体，常导致高死亡率和重大经济损失，因此开发治疗方法来对抗这种病原体具有重要的商业意义。绿茶是一种著名的药用植物，含有具有抗病毒、抗菌等生物活性的成分。本研究的目的是探讨绿茶源化合物对 LMBV 的作用和机制，为今后靶向药物的筛选提供数据基础。在这项研究中，我们评估了绿茶的主要成分表没食子儿茶素没食子酸酯（EGCG）对 LMBV 感染的影响。
(2) 方法：通过细胞活力检测和相差显微镜确定 EGCG 的安全工作浓度。通过相差显微镜、基于适体的 6-羧基荧光素荧光分子探针和反转录定量 PCR 评估 EGCG 对 LMBV 感染的抗病毒活性和作用机制。
(3) 结果：EGCG 的安全工作浓度≤10 μg/mL。EGCG 呈浓度依赖性显著抗 LMBV 感染活性，并且破坏病毒粒子的结构。EGCG 影响病毒粒子与细胞受体的结合和病毒侵入宿主细胞。EGCG 对 LMBV 粒子、LMBV 与宿主细胞膜的结合和 LMBV 入侵的抑制作用分别为 84.89%、98.99%和 95.23%。同时，在体内验证了 EGCG 的作用。LMBV+EGCG 组的死亡率明显低于 LMBV 组。
(4) 结论：我们的结果表明，EGCG 对 LMBV 具有有效的抗病毒特性，可能是有效治疗和控制大口黑鲈养殖业中 LMBV 感染的候选药物。
