Dental workers in front-line of COVID-19: an in silico evaluation targeting their prevention

Abstract SARS-CoV-2 has high human-human transmission rate. The aerosols and saliva droplets are the main contamination source. Thus, it is crucial to point out that dental practitioners become a high-risk group of contagion by SARS-CoV-2. Based on this, protocols have been recommended to avoid cross-contamination during dental care; however, appropriate evidence has not yet been established. Objective Our study sought to make a screening, by in silico analysis, of the potential of mouth rinses used in dental practices to prevent the dental workers' contamination by SARS-CoV-2. Methodology Multiple sequence comparisons and construction of the phylogenetic tree were conducted using the FASTA code. Therefore, molecular docking investigation between SARS-CoV-2 proteins (Main Protease, Spike Glycoprotein, Non-structure Protein, and Papain-like Protease) and molecules used in dental practices (chlorhexidine digluconate, hydrogen peroxide, cetylpyridinium chloride, povidone-iodine, gallic acid, β-cyclodextrin, catechin, and quercetin) was performed using AutoDock Vina. Moreover, 2D interactions of the complex protein-ligand structure were analyzed by Ligplot+. Results The obtained results showed a remarkable affinity between SARS-CoV-2 proteins and all tested compounds. The chlorhexidine digluconate, catechin, and quercetin presented a higher affinity with SARS-CoV-2. Conclusions The overall results allowed us to suggest that chlorhexidine is the most suitable active compound in reducing the SARS-CoV-2 salivary load due to its better binding energy. However, in vivo studies should be conducted to confirm their clinical use.

摘要 严重急性呼吸综合征冠状病毒2（SARS-CoV-2）具备极高的人际传播效率，气溶胶与唾液飞沫为其主要污染来源。由此可见，牙科医护人员属于SARS-CoV-2感染的高风险人群，这一点至关重要。基于此，学界已推荐采用相关诊疗规范以规避牙科诊疗过程中的交叉污染，但目前尚未形成充分的循证依据。
研究目的 本研究旨在通过计算机模拟（in silico）分析，筛选牙科临床常用漱口液预防牙科医护人员感染SARS-CoV-2的潜力。
研究方法 本研究采用FASTA代码开展多序列比对与系统发育树构建；使用AutoDock Vina对SARS-CoV-2相关蛋白（主蛋白酶（Main Protease）、刺突糖蛋白（Spike Glycoprotein）、非结构蛋白（Non-structure Protein）以及木瓜样蛋白酶（Papain-like Protease））与牙科临床常用分子（葡萄糖酸氯己定（chlorhexidine digluconate）、过氧化氢（hydrogen peroxide）、氯化十六烷基吡啶（cetylpyridinium chloride）、聚维酮碘（povidone-iodine）、没食子酸（gallic acid）、β-环糊精（β-cyclodextrin）、儿茶素（catechin）以及槲皮素（quercetin））进行分子对接研究；此外，通过Ligplot+分析蛋白-配体复合物的二维相互作用。
研究结果 本研究结果显示，SARS-CoV-2蛋白与所有受试化合物均表现出显著结合亲和力；其中葡萄糖酸氯己定、儿茶素与槲皮素与SARS-CoV-2蛋白的结合亲和力更高。
研究结论 综合上述结果，本研究提示葡萄糖酸氯己定凭借更优的结合能，是降低SARS-CoV-2唾液载量的最优活性成分。不过仍需开展体内（in vivo）实验以验证其临床应用价值。