Data Sheet 1_Honeysuckle extracts as a potential inhibitor of SARS-CoV-2 infection.docx

BackgroundIn the current era of coronavirus disease 2019 (COVID-19), we were interested in searching for medications other than the currently available antiviral drugs Paxlovid and Molnupiravir that cause minimal side effects and do not harm the human body. Honeysuckle extract (HSE) is a traditional Chinese medicine (TCM) that has been shown to exert antiviral effects in other studies. However, no studies have indicated whether HSE has an inhibitory effect on SARS-CoV-2.
MethodsWe prepared HSEs from dried honeysuckle flowers. We performed a cell viability assay, median tissue culture infection dose (TCID50) assay, and qRT‒PCR, and calculated the virus titers using the Reed-Muench method to evaluate the inhibitory effects of aqueous and alcohol HSEs on SARS‒CoV‒2 and explore the possible underlying mechanisms.
ResultsIn this study, post-treatment with HSE resulted in dose-dependent decreases in both the RNA levels and TCID50 of SARS-CoV-2 in Vero E6 cells; treatment with 50 μg/ml and 100 μg/ml alcohol HSEs achieved up to 95.323% and 92.587% inhibition, respectively. Moreover, pre-treatment with aqueous HSEs effectively reduced the RNA levels, and TCID50 of SARS-CoV-2 by up to 99.684%, and alcohol HSEs achieved up to 99.921% inhibition; both of these effects occurred in a dose-dependent manner.
ConclusionThe results suggest that HSEs may have the potential to prevent SARS-CoV-2 infection.

背景：在当前新型冠状病毒肺炎（coronavirus disease 2019, COVID-19）大流行背景下，本研究旨在探寻除现有抗病毒药物帕昔洛韦（Paxlovid）与莫努匹拉韦（Molnupiravir）之外、副作用轻微且对人体无害的治疗药物。金银花提取物（Honeysuckle Extract, HSE）作为一种传统中药（Traditional Chinese Medicine, TCM），既往研究已证实其具备抗病毒活性，但尚无研究明确其是否对严重急性呼吸综合征冠状病毒2（SARS-CoV-2）具有抑制效果。
方法：本研究以干燥金银花为原料制备金银花提取物，通过细胞活力测定、半数组织培养感染量（median tissue culture infection dose, TCID50）测定、实时荧光定量聚合酶链反应（quantitative real-time polymerase chain reaction, qRT-PCR）实验，并采用Reed-Muench法计算病毒滴度，以此评估水提金银花提取物与醇提金银花提取物对严重急性呼吸综合征冠状病毒2的抑制作用，并探究其潜在作用机制。
结果：本研究结果显示，在Vero E6细胞中，金银花提取物的病毒感染后处理可呈剂量依赖性降低严重急性呼吸综合征冠状病毒2的RNA水平与TCID50值：当醇提金银花提取物浓度为50 μg/ml与100 μg/ml时，抑制率分别可达95.323%与92.587%。此外，水提金银花提取物的病毒感染前处理可有效降低严重急性呼吸综合征冠状病毒2的RNA水平与TCID50值，最高抑制率达99.684%；醇提金银花提取物的最高抑制率可达99.921%，且上述作用均呈剂量依赖性。
结论：本研究结果表明，金银花提取物具备预防严重急性呼吸综合征冠状病毒2感染的潜在应用价值。