Effects of high polyphenol doses on the replication of COVID-19 in vitro

SARS-CoV-2的爆发引发了前所未有的全球卫生危机。这种传染性病毒的致死率在总体受影响人群中接近2%，在老年人中超过15%。迄今为止，还没有批准用于治疗这种病毒性疾病的药物或疫苗。这种RNA病毒与SARS-CoV-1有关，SARS-CoV-1是2002- 2003年在中国出现的一种相关病毒，但具有引起特定病态症状的明显特征。在实际大流行的背景下，迫切需要重新审视传统药典中已经开发的具有潜在抗病毒作用的合成药物和天然分子库。由于药物的剂量、副作用、配方和毒性已经已知，将分子重新分类为新的抗病毒用途可以提供一种快速开发和推荐药物的方法。在天然药用植物药典中，黄酮类化合物似乎有希望对抗SARS-CoV-2。事实上，它们对流感、寨卡病毒、埃博拉病毒、肝炎、艾滋病毒等多种病毒都有抗病毒活性。表没食子儿茶素没食子酸酯、槲皮素、橙皮苷等黄酮类化合物因其在重要病毒蛋白结合位点上的高对接能力而成为进一步活性测试的候选分子。值得注意的是，前三种分子分别在绿茶、洋葱和柑橘中含量很高。可以使用相对简单的协议适配的现有技术有效地提取它们。最有趣的是，对这些产品的毒理学已经进行了充分的研究，加拿大卫生部已经有专著描述了它们公认的传统用途、毒性和副作用。我们假设黄酮类化合物具有阻止SARS-CoV-2在Vero细胞中的复制的抑制作用，并且有可能开发出有效的提取方案，用于在体外筛选阶段鉴定的生物活性分子。我们将特别评估7种多酚（EGCG、槲皮素、异槲皮素、橙皮苷、儿茶素、原花青素、儿茶素、阿魏酸）对SARS-CoV-2体外复制的影响，并制定从不同来源的原料中提取这些分子的方案。

The SARS-CoV-2 outbreak in causing an unprecedented global sanitary crisis. The contagious virus has a lethal rate of close to 2% death in the overall affected population and more than 15 % in elderly people. To date, there are no medications or vaccines approved for the treatment of this viral disease. This RNA virus is associated to SARS-CoV-1, a related virus which emerged in 2002-03 in China, but has distinct features provoking specific morbid symptoms. In the context of the actual pandemic, it is urgent to revisit the arsenal of already developed synthetic drugs and natural molecules from the traditional pharmacopeia with potential action against the virus. The reclassification of a molecule to a new anti-viral use can provide a rapid approach to develop and recommend a drug since its dosage, side effects, formulation and toxicity are already known. Among the pharmacopeia of natural medicinal plants, flavonoids appear promising to fight SARS-CoV-2. Indeed, they display antiviral activity against a number of viruses such as influenza, Zika, Ebola, hepatitis, HIV and many others. Epigallocatechin gallate, quercetin, hesperidin, all flavonoids, are candidate molecules for further activity testing owing to their high-docking capacity on important virus protein binding sites. Noteworthy is the fact that the first three molecules are found in high concentrations in green tea, onions, and citrus respectively. They can be extracted efficiently using available technologies with relatively simple protocol adaptation. Most interestingly, the toxicology of these products has been amply studied and Health Canada already has monographies describing their accepted traditional use, toxicity and side effects. We hypothesize that flavonoids have an inhibitory action preventing the replication of SARS-CoV-2 in Vero cells and that it is possible to develop efficient extraction protocols for the bioactive molecules identified during the in vitro screening phases. We will in particular evaluate, 7 polyphenols (EGCG, quercetin, isoquercetin, hesperidin, catechin, proanthocyanidins, catechins, ferulic acid) on replication of SARS-CoV-2 in vitro and develop protocols for the extraction of these molecules from different sources of raw product.