表没食子儿茶素没食子酸酯对甲型流感病毒致宿主细胞氧化应激损伤的影响

Protection in vitro of Epigallocatechin Gallate on Oxidative Stress Induced by Influenza Infection

摘要:

目的: 研究表没食子儿茶素没食子酸酯(EGCG)在体外对甲型流感病毒感染后氧化应激的影响,初步探讨EGCG抗流感病毒的发生机制。 方法: 以1×10⁴个细胞密度接种96 孔板,在体外用MTT法检测不同浓度EGCG对狗肾传代细胞(MDCK)的毒性浓度;病毒感染28 h后,用CPE观察法、血凝法、实时定量荧光PCR法评价EGCG对甲型流感病毒的抑制作用;并通过共聚焦显微技术和流式细胞术,探寻EGCG对甲型流感病毒感染后氧化应激的影响。 结果: EGCG在体外能有效抑制甲型流感病毒的复制,病毒抑制率与感染后加药时间正相关(P<0.05);与病毒对照相比,20 mg·L^-1 EGCG处理后流感病毒感染的MDCK细胞中活性氧的水平下降54%,继而有效抑制流感病毒引起的细胞凋亡。 结论: EGCG主要抑制流感病毒的早期复制,可通过调控氧化应激,抑制流感病毒所致MDCK细胞凋亡。

Abstract:

Objective:To investigate the molecular mechanism of the anti-influenza A virus effects of epigallocatechin gallate(EGCG) derived from green tea in vitro. Method: The cell viability of EGCG was determined by using MTT assay. And virus inhibitory rate was evaluated based on the observation of cytopathic effect (CPE), hemagglutination assay and Real-time Quantitative PCR (QPCR). The mechanisms of action for the observed sensitivity of influenza A to EGCG at the molecular level was assessd by confocal microscope and flow cytometry. Result: Exposing Madin-Darby canine kidney (MDCK) cells with 20 mg·L^-1 EGCG could inhibit influenza A replication in a time-dependent manner, probably by interrupting postbinding step. EGCG treatment could mitigate oxidative stress in influenza-infected cells and reduce the apoptosis induced by influenza infection. Conclusion: EGCG inhibits oxidative stress and apoptosis induced by influenza virus infection.