严重急性呼吸综合征冠状病毒2膜蛋白对宿主细胞pre-mRNA 3"UTR加工的影响

目的 研究严重急性呼吸综合征冠状病毒2（SARS-CoV-2）膜蛋白对宿主细胞mRNA前体（pre-mRNA）3"非翻译区（UTR）加工的影响。方法 本研究以人肺上皮细胞系A549为模型，利用瞬时转染在细胞内过表达SARS-CoV-2膜蛋白；利用RNA-Seq测序技术及生物信息学分析方法，系统性描绘宿主细胞选择性多聚腺苷酸化（alternative polyadenylation，APA）事件；Metascape数据库对发生显著APA变化的基因进行功能富集分析；RT-qPCR验证靶基因3"UTR长度变化；蛋白质免疫印迹（Western blot）检测目的蛋白表达水平。结果 SARS-CoV-2膜蛋白外源表达后宿主细胞内共813个基因发生显著APA变化。GO和KEGG分析显示，差异APA基因广泛参与有丝分裂细胞周期、调节细胞应激等生物过程，涉及病毒感染和蛋白质加工等。从中进一步筛选出AKT1基因，在IGV软件中显示3"UTR延长；RT-qPCR验证AKT1基因的3"UTR长度变化趋势；Western blot结果显示AKT1蛋白磷酸化水平增加。结论 SARS-CoV-2膜蛋白潜在影响宿主pre-mRNA的3"UTR加工，其中参与多种病毒性生物过程的AKT1基因 3"UTR延长，且其编码的蛋白质功能在细胞内被激活。     

低心血管疾病风险选择性环氧合酶-2抑制剂的虚拟筛选

摘要 目的：寻找具有血栓素A2受体（Thromboxane A2 receptor,TP）抑制作用的选择性环氧合酶-2（Cyclooxygenase-2,COX-2）抑制剂,以期降低其心血管疾病风险。方法：本研究从公开数据库中获取了512种TP抑制剂,通过分子对接、分子动力学模拟和ADMET预测,筛选出化合物TP84。结果：分子对接结果显示,与先前获批的选择性COX-2抑制剂罗非昔布相比,TP84对COX-2的亲和力更高,对环氧合酶-1（Cyclooxygenase-1,COX-1）的亲和力更低;分子动力学模拟进一步表明,模拟过程中TP84与COX-1的结合不稳定,而TP84能稳定结合COX-2,与COX-2的结合自由能是COX-1的3倍;此外,根据ADMET预测,TP84的药物化学、吸收、分布、代谢、排泄和毒性处于类药物候选物的可接受范围内。结论：TP84是一种潜在的低心血管疾病风险选择性COX-2抑制剂。     

苍耳子提取物抗类过敏作用及活性成分筛选的研究

摘要 目的：探讨苍耳子提取物抗类过敏作用及筛选出其中的活性成分。方法：采用测量小鼠脚掌肿胀和组织液渗出,检测小鼠血清中组胺、肿瘤坏死因子-α（tumor necrosis factor-α,TNF-α）、单核细胞趋化因子-1（monocyte chemotactic protein-1,MCP-1）和白细胞介素-8（interleukin-8,IL-8）浓度,检测肥大细胞脱颗粒的方法,观察苍耳子提取物拮抗C48/80诱发的类过敏反应的作用。建立高表达MrgX2/CMC筛选模型,从苍耳子的10种成分中筛选可作用于MrgX2受体的抗类过敏活性成分。结果：苍耳子提取物可减轻C48/80导致的小鼠脚掌肿胀和组织液渗出,降低小鼠血清中组胺、TNF-α、MCP-1和IL-8的含量,抑制肥大细胞脱颗粒（P<0.05）。10种苍耳子成分中筛选出6种有保留成分,其中槲皮素和大黄素可显著抑制肥大细胞释放组胺（P<0.05）。结论：苍耳子提取物可抑制肥大细胞脱颗粒和致敏介质的释放,其成分中槲皮素和大黄素具有潜在的抗类过敏作用。     

苦绳（Dregea sinensis）中多氧化孕烷糖苷与免疫蛋白相互作用的研究

目的 基于化学结构特点研究植物苦绳（Dregea sinensis）中多氧孕烷糖苷的生物活性,以及化合物分子与靶蛋白分子间的作用机理。方法 本研究采用分子对接和表面等离子体共振方法,对191个多氧化孕烷糖苷类成分（>800 u）进行了免疫活性及其与免疫蛋白的动力学评价。结果 通过分子对接方法筛选出7个配体分子（6、18、23、30、78、79和80）和3个免疫相关蛋白（IL-2Rα、TLR4和TNF-α）。研究表明,化合物30和78在SPR实验中与靶蛋白IL-2Rα和TLR4具有显著的结合趋势,与IL-2Rα的结合常数K_D分别为2.41×10^-6和2.14×10^-6 mol/L,与TLR4则分别为1.96×10^-5和5.60×10^-6 mol/L。分子动力学研究进一步表征SPR阳性分子6、18、30、78和80与靶蛋白之间的相互作用基团。结论 研究揭示多氧化孕烷糖苷类成分可以通过形成氢键和Pi-Pi相互作用与靶蛋白结合。研究内容对快速评价多氧化孕烷糖苷类成分的活性具有重要意义,为揭示低丰度药效物质的潜在作用机制进行了有益探索。     

二氢丹参酮通过抑制Akt信号通路激活来增强索拉非尼对肝细胞癌的抗癌作用

目的 索拉非尼是唯一被批准用于治疗晚期肝细胞癌（hepatocellular carcinoma,HCC）的一线药物。然而索拉非尼的耐药性使得治疗效果并不理想。尽管索拉非尼耐药性的机制尚不清楚,但在HCC中的耐药性可能通过Akt信号通路的激活而发生。二氢丹参酮（dihydrotanshinone,DHT）是中药丹参的亲脂性成分,具有多种抗肿瘤活性并可抑制Akt活化。DHT联合索拉非尼治疗HCC的作用机制尚未明确。本文旨在研究DHT是否可增强索拉非尼对HCC的抗癌活性。方法 采用细胞计数试剂盒8（cell counting kit-8,CCK-8）和流式细胞仪检测索拉非尼和DHT对HCC细胞Huh7和HepG2细胞活力、细胞凋亡和药物敏感性的影响。通过蛋白质印迹分析Akt、P-Akt、Caspase3、GSK-3β、P-GSK3-β、核糖体蛋白S6激酶（S6K）、P-S6K、细胞周期蛋白D1、Bcl-xl、Bcl-2和Bax的表达水平。使用单因素方差分析（analysis of variance,ANOVA）和Dunnett检验对所有数据进行统计学比较。采用SPSS 20.0统计软件进行统计分析。结果 DHT通过减少Akt的激活来抑制HCC细胞的增殖和促进细胞凋亡。DHT抑制Akt下游因子的表达和激活,包括GSK-3β和S6K,这些因子调节细胞凋亡反应,并被索拉非尼激活和上调。索拉非尼和DHT均下调细胞周期蛋白D1的表达,DHT上调Bax的表达并下调Bcl-2和Bcl-xl的表达。索拉非尼对Bcl-2家族蛋白质表达的影响不大。结论 DHT可能通过抑制Akt信号通路的激活来增强索拉非尼的HCC细胞增殖抑制作用和凋亡诱导作用。     

基于网络药理学探讨皂角刺治疗乳痈的作用机制

摘要 目的：基于网络药理学探讨皂角刺治疗乳痈的作用机制。方法：通过建立皂角刺药物靶点数据集、乳痈相关疾病靶点数据集，构建皂角刺治疗急性乳腺炎的蛋白互作（PPI）网络，构建并分析"皂角刺活性成分-潜在靶点-急性乳腺炎"网络。开展基因本体（GO）功能富集分析和京都基因与基因组百科全书（KEGG）通路富集分析，探讨皂角刺治疗乳痈的可能机制。结果：共得到皂角刺活性成分11个，筛选出活性成分所对应的不重复靶点共97个，其中1个活性成分无对应靶点。通过搜集GeneCards 和OMIM数据库，共得到292个急性乳腺炎的相关靶点基因。将疾病靶点基因与药物活性成分所对应的靶点进行比对后，得到10个交集靶点，即皂角刺治疗急性乳腺炎的潜在靶点。皂角刺活性成分按degree值排前3名的依次为槲皮素（quercetin）、漆黄素（fisetin）、山奈酚（kaempferol），其中皂角刺治疗乳痈的靶点包括白细胞介素-6（IL-6）、表皮生长因子受体（EGFR）、酪氨酸激酶受体2（ERBB2）、细胞间黏附分子-1（ICAM1）、雌激素受体1（ESR1）等5个关键靶点，主要涉及乳腺癌疾病通路、TNF信号通路和雌激素信号通路等3条信号通路。结论：皂角刺治疗乳痈的作用机制可能与机体的炎症反应以及雌激素水平变化等密切相关。     

研究报告: 基于Ser-SELEX技术的结肠癌血清适配体的筛选及其应用研究

目的 为了解决癌症早期诊断困难的问题，实现结肠癌的早期检测。方法 采用Ser-SELEX技术筛选了结肠癌血清的特异性适配体。通过前期结肠癌血清正筛-正常人血清反筛步骤和后期结肠癌血清正筛-其他癌症血清反筛步骤循环的方式，经过16轮筛选流程，共选取4条候选适配体，并对其进行序列分析、二级结构和三级结构模拟、特异性分析等。结果 候选适配体主要形成的结构是茎环和假结两种，qPCR法测试亲和力，K_d约为10 nmol/L，适配体与结肠癌患者血清特异性结合情况分析表明，候选适配体APT-2具有良好特异性，且此种方法检出率约为 82.5%。结论 适配体（APT-2）应用于结肠癌早期诊断具有良好的发展前景。     

新型冠状病毒相关靶点小分子抑制剂虚拟筛选

为确定治疗新型冠状病毒(SARS-CoV-2)感染的候选药物,开展了针对SARS-CoV-2的药物虚拟筛选研究。以SARS-CoV-2的刺突蛋白(S蛋白)和3CL蛋白酶(主蛋白酶)作为药物靶点,以美国食品药品监督管理局(FDA)批准上市的2 726个小分子药物作为候选,通过分子对接方法,筛选出了3种(阿巴瑞克(Abarelix)、西曲瑞克(Cetrorelix)、鞣酸(Tannic acid))与S蛋白具有较强结合能力的小分子药物,1种(戈舍瑞林(Goserelin))与3CL蛋白酶具有较好结合能力的小分子药物,它们理论上都具有抑制新型冠状病毒复制的效果。将靶向3CL蛋白酶的候选药物与辉瑞公司开发的药物Paxlovid进行比较,发现其作用位点均集中于3CL蛋白酶的第130-200位的残基周围,具有相似的结合位点与相互作用。此外也对候选药物的物理与化学性质及与基因相互作用进行了分析。本研究可为开发新型冠状病毒感染的治疗药物提供参考。     

大黄酸调节Ras/ERK信号通路对肝细胞癌细胞增殖、迁移和侵袭的影响

摘要 目的：探讨大黄酸调节大鼠肉瘤蛋白（Ras）/胞外信号调控激酶（ERK）信号通路对肝细胞癌（HCC）细胞增殖、迁移和侵袭的影响。方法：使用不同浓度（0、12.50、25、50、100、150、200 mol/L）大黄酸处理HepG2细胞,检测细胞活性,筛选最佳大黄酸浓度。将细胞分为对照组、大黄酸低、中、高浓度组、大黄酸高浓度+Ras/ERK激活剂组（大黄酸高浓度+ML-099组）,分别检测各组细胞集落形成数、划痕愈合率、细胞侵袭数和Ras、p-ERK、ERK蛋白表达。结果：大黄酸以浓度和时间依赖性降低HepG2细胞活性（P<0.05）,选用25、50、100 mol/L处理HepG2细胞24 h用于后续实验;与对照组比较,大黄酸低、中、高浓度组细胞集落形成数、G0/G1细胞比例、细胞划痕愈合率、细胞侵袭数和原癌基因（c-Myc）、细胞周期蛋白D1（CyclinD1）、Ras、p-ERK/ERK蛋白表达呈浓度依赖性降低,S期和G2/M细胞比例、p53蛋白表达呈浓度依赖性增加（P<0.05）;与大黄酸高浓度组比较,大黄酸高浓度+ML-099组细胞集落形成数、G0/G1细胞比例、细胞划痕愈合率、细胞侵袭数和c-Myc、CyclinD1、Ras、p-ERK/ERK蛋白表达显著增加,S期和G2/M细胞比例、p53蛋白表达显著降低（P<0.05）。结论：大黄酸可能通过抑制Ras/ERK信号通路抑制HCC细胞增殖、迁移和侵袭。     

血清钙结合蛋白S100A12、脂联素及IL-17与稳定期COPD患者严重程度及肺功能的相关性

摘要 目的：探讨血清钙结合蛋白S100A12、脂联素及白细胞介素-17（Interleukin-17,IL-17）水平与稳定期慢性阻塞性肺疾病（COPD）病情严重程度和肺功能的关系。方法：选择稳定期COPD患者（稳定期COPD组）和健康体检者（对照组）各80例,稳定期COPD患者分为四级：I级轻度（22例）,Ⅱ级中度（24例）,Ⅲ级重度（19例）,Ⅳ级极重度（15例）。使用肺功能仪对所有研究对象的肺功能进行检查,采用血气分析仪检测动脉血中的氧分压 (PaO₂) 和二氧化碳分压 (PaCO₂),采用酶联免疫吸附试验检测血清中钙结合蛋白S100A12、脂联素和IL-17水平,采用 Pearson相关分析各指标之间的相关性。结果：稳定期COPD组肺功能[第一秒用力呼出气量容积占预计值百分比（FEV₁%）和第一秒用力呼出气量容积/用力肺活量（FEV1/FVC%）]和PaO₂显著低于对照组（P<0.05）,并随着COPD严重程度增加而降低（P<0.05）;稳定期COPD组血清钙结合蛋白S100A12、脂联素、IL-17水平和PaCO₂均高于对照组（P<0.05）,并随COPD严重程度增加而升高（P <0.05）。Pearson相关分析显示：稳定期COPD患者血清钙结合蛋白S100A12、脂联素和IL-17水平与FEV₁%、FEV₁/FVC%和PaO₂呈负相关（P<0.05）,与PaCO₂呈正相关（P<0.05）。结论：钙结合蛋白S100A12、脂联素和IL-17可能共同参与了稳定期COPD慢性炎症过程,引起气流受限,影响肺通气功能,可以辅助评估稳定期COPD病情的严重程度。     

Screening of inhibitors against SARS-CoV-2 spike protein and their capability to block the viral entry mechanism: A viroinformatics study

SARS-CoV-2, previously named 2019 novel coronavirus (2019-nCoV), has been associated with the global pandemic of acute respiratory distress syndrome. First reported in December 2019 in the Wuhan province of China, this new RNA virus has several folds higher transmission among humans than its other family member (SARS-CoV and MERS-CoV). The SARS-CoV-2 spike receptor-binding domain (RBD) is the region mediating the binding of the virus to host cells via Angiotensin-converting enzyme 2 (ACE2), a critical step of viral. Here in this study, we have utilized in silico approach for the virtual screening of antiviral library extracted from the Asinex database against the Receptor binding domain (RBD) of the S1 subunit of the SARS-CoV-2 spike glycoprotein. Further, the molecules were ranked based on their binding affinity against RBD, and the top 15 molecules were selected. The affinity of these selected molecules to interrupt the ACE2-Spike interaction was also studied. It was found that the chosen molecules were demonstrating excellent binding affinity against spike protein, and these molecules were also very effectively interrupting the ACE2-RBD interaction.Furthermore, molecular dynamics (MD) simulation studies were utilized to investigate the top 3 selected molecules' stability in the ACE2-RBD complexes. To the best of our knowledge, this is the first study where molecules' inhibitory potential against the Receptor binding domain (RBD) of the S1 subunit of the SARS-CoV-2 spike glycoprotein and their inhibitory potential against the ACE2-Spike has been studied. We believe that these compounds can be further tested as a potential therapeutic option against COVID-19.     

Identification of putative antiviral bioactive compounds derived from family Asteraceae: An in silico approach

This computational study investigates 21 bioactive compounds from the Asteraceae family as potential inhibitors targeting the Spike protein (S protein) of SARS-CoV-2. Employing in silico methods and simulations, particularly CDOCKER and MM-GBSA, the study identifies two standout compounds, pterodontic acid and cichoric acid, demonstrating robust binding affinities (−46.1973 and −39.4265 kcal/mol) against the S protein. Comparative analysis with Favipiravir underscores their potential as promising inhibitors. Remarkably, these bioactives exhibit favorable ADMET properties, suggesting safety and efficacy. Molecular dynamics simulations validate their stability and interactions, signifying their potential as effective SARS-CoV-2 inhibitors.     

Caffeic acid derivatives (CAFDs) as inhibitors of SARS-CoV-2: CAFDs-based functional foods as a potential alternative approach to combat COVID-19

BackgroundSARS-CoV-2, an emerging strain of coronavirus, has affected millions of people from all the continents of world and received worldwide attention. This emerging health crisis calls for the urgent development of specific therapeutics against COVID-19 to potentially reduce the burden of this emerging pandemic.PurposeThis study aims to evaluate the anti-viral efficacy of natural bioactive entities against COVID-19 via molecular docking and molecular dynamics simulation.MethodsA library of 27 caffeic-acid derivatives was screened against 5 proteins of SARS-CoV-2 by using Molegro Virtual Docker 7 to obtain the binding energies and interactions between compounds and SARS-CoV-2 proteins. ADME properties and toxicity profiles were investigated via www.swissadme.ch web tools and Toxtree respectively. Molecular dynamics simulation was performed to determine the stability of the lead-protein interactions.ResultsOur obtained results has uncovered khainaoside C, 6-O-Caffeoylarbutin, khainaoside B, khainaoside C and vitexfolin A as potent modulators of COVID-19 possessing more binding energies than nelfinavir against COVID-19 M^pro, Nsp15, SARS-CoV-2 spike S2 subunit, spike open state and closed state structure respectively. While Calceolarioside B was identified as pan inhibitor, showing strong molecular interactions with all proteins except SARS-CoV-2 spike glycoprotein closed state. The results are supported by 20 ns molecular dynamics simulations of the best complexes.ConclusionThis study will hopefully pave a way for development of phytonutrients-based antiviral therapeutic for treatment or prevention of COVID-19 and further studies are recommended to evaluate the antiviral effects of these phytochemicals against SARS-CoV-2 in in vitro and in vivo models.     

Abrogation of AuroraA-TPX2 by novel natural inhibitors: molecular dynamics-based mechanistic analysis

Abstract

Introduction: Cancer is characterized by uncontrolled cell growth and genetic instabilities. The human Aurora-A kinase protein plays a crucial role in spindle assembly during mitosis and is activated by another candidate oncogene, targeting protein for Xklp2 (TPX2). It has been proposed that dissociation of Aurora A–TPX2 complex leads to disruption of mitotic spindle apparatus, thereby preventing cell division and further tumor growth. Materials and methods: A large natural compound library was docked against the active site of Aurora A–TPX2 complex. The protein–ligand complexes were subjected to molecular dynamics simulation to ascertain their binding stability. The drug properties of the compounds were analyzed to observe their drug-like properties. Results: The virtual screening of natural compound library yielded two high scoring compounds, the first compound CTOM [ZINC ID: 38143674] (Glide score: –9.49) was stable for 17 ns while the second TTOM (Glide score: ?9.07) was stable for 15 ns. While CTOM interacted with His280, Thr288 of Aurora A and Tyr34, Lys38 of TPX2, TTOM interacted with Arg285 and Arg286 in addition to the residues involved with CTOM. Conclusions: We report two natural compounds as potential drugs leads for the disruption of this complex. These ligands show a preferable docking score and have many drugs like properties within in the range of 95% of known drugs. The study provides evidence that CTOM and TTOM can efficiently inhibit the TPX2-mediated activation of Aurora A. Thus, it paves way for an elaborate investigation and establishes the importance of computational approaches as time- and cost-effective techniques.     

Network pharmacology,molecular docking integrated surface plasmon resonance technology reveals the mechanism of Toujie Quwen Granules against coronavirus disease 2019 pneumonia

BackgroundThe Coronavirus disease 2019 pneumonia broke out in 2019 (COVID-19) and spread rapidly, which causes serious harm to the health of people and a huge economic burden around the world.PurposeIn this study, the network pharmacology, molecular docking and surface plasmon resonance technology (SPR) were used to explore the potential compounds and interaction mechanism in the Toujie Quwen Granules (TQG) for the treatment of coronavirus pneumonia 2019.Study designThe chemical constituents and compound targets of Lonicerae Japonicae Flos, Pseudostellariae Radix, Artemisia Annua L, Peucedani Radix, Forsythiae Fructus, Scutellariae Radix, Hedysarum Multijugum Maxim, Isatidis Folium, Radix Bupleuri, Fritiliariae Irrhosae Bulbus, Cicadae Periostracum, Poria Cocos Wolf, Pseudobulbus Cremastrae Seu Pleiones, Mume Fructus, Figwort Root and Fritillariae Thunbrgii Bulbus in TQG were searched. The target name was translated to gene name using the UniProt database and then the Chinese medicine-compound-target network was constructed. Protein-protein interaction network (PPI), Gene ontology (GO) function enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of the core targets were performed in the Metascape to predict its mechanism. The top 34 compounds in the Chinese medicine-compound-target network were docked with SARS-CoV-2 3CL enzyme and SARS-­CoV­-2 RNA-dependent RNA polymerase (RdRp) and then the 13 compounds with lowest affinity score were docked with angiotensin-converting enzyme 2 (ACE2), SARS-CoV-2 Spike protein and interleukin 6 to explore its interaction mechanism. Lastly, SPR experiments were done using the quercetin, astragaloside IV, rutin and isoquercitrin, which were screened from the Chinese medicine-compound-target network and molecular docking.ResultsThe Chinese medicine-compound-target network includes 16 medicinal materials, 111 compounds and 298 targets, in which the degree of PTGS2, TNF and IL­6 is higher compared with other targets and which are the disease target exactly. The result of GO function enrichment analysis included the response to the molecule of bacterial origin, positive regulation of cell death, apoptotic signaling pathway, cytokine-mediated signaling pathway, cytokine receptor binding and so on. KEGG pathway analysis enrichment revealed two pathways: signaling pathway­ IL-17 and signaling pathway­ TNF. The result of molecular docking showed that the affinity score of compounds including quercetin, isoquercitrin, astragaloside IV and rutin is higher than other compounds. In addition, the SPR experiments revealed that the quercetin and isoquercitrin were combined with SARS-CoV-2 Spike protein rather than Angiotensin-converting enzyme 2, while astragaloside IV and rutin were combined with ACE2 rather than SARS-CoV-2 Spike protein.ConclusionTQG may have therapeutic effects on COVID-19 by regulating viral infection, immune and inflammation related targets and pathways, in the way of multi-component, multi-target and multi-pathway.     

Corilagin prevents SARS-CoV-2 infection by targeting RBD-ACE2 binding

BackgroundThe outbreak of coronavirus (SARS-CoV-2) disease caused more than 100,000,000 people get infected and over 2,200,000 people being killed worldwide. However, the current developed vaccines or drugs may be not effective in preventing the pandemic of COVID-19 due to the mutations of coronavirus and the severe side effects of the newly developed vaccines. Chinese herbal medicines and their active components play important antiviral activities. Corilagin exhibited antiviral effect on human immunodeficiency virus (HIV), hepatitis C virus (HCV) and Epstein-Barr virus (EBV). However, whether it blocks the interaction between SARS-CoV-2 RBD and hACE2 has not been elucidated.PurposeTo characterize an active compound, corilagin derived from Phyllanthus urinaria as potential SARS-CoV-2 entry inhibitors for its possible preventive application in daily anti-virus hygienic products.MethodsComputational docking coupled with bio-layer interferometry, BLI were adopted to screen more than 1800 natural compounds for the identification of SARS-CoV-2 spike-RBD inhibitors. Corilagin was confirmed to have a strong binding affinity with SARS-CoV-2-RBD or human ACE2 (hACE2) protein by the BLI, ELISA and immunocytochemistry (ICC) assay. Furthermore, the inhibitory effect of viral infection of corilagin was assessed by in vitro pseudovirus system. Finally, the toxicity of corilagin was examined by using MTT assay and maximal tolerated dose (MTD) studies in C57BL/6 mice.ResultsCorilagin preferentially binds to a pocket that contains residues Cys 336 to Phe 374 of spike-RBD with a relatively low binding energy of -9.4 kcal/mol. BLI assay further confirmed that corilagin exhibits a relatively strong binding affinity to SARS-CoV-2-RBD and hACE2 protein. In addition, corilagin dose-dependently blocks SARS-CoV-2-RBD binding and abolishes the infectious property of RBD-pseudotyped lentivirus in hACE2 overexpressing HEK293 cells, which mimicked the entry of SARS-CoV-2 virus in human host cells. Finally, in vivo studies revealed that up to 300 mg/kg/day of corilagin was safe in C57BL/6 mice. Our findings suggest that corilagin could be a safe and potential antiviral agent against the COVID-19 acting through the blockade of the fusion of SARS-CoV-2 spike-RBD to hACE2 receptors.ConclusionCorilagin could be considered as a safe and environmental friendly anti-SARS-CoV-2 agent for its potential preventive application in daily anti-virus hygienic products.     

Berbamine hydrochloride potently inhibits SARS-CoV-2 infection by blocking S protein-mediated membrane fusion

COVID-19 caused by SARS-CoV-2 has posed a significant threat to global public health since its outbreak in late 2019. Although there are a few drugs approved for clinical treatment to combat SARS-CoV-2 infection currently, the severity of the ongoing global pandemic still urges the efforts to discover new antiviral compounds. As the viral spike (S) protein plays a key role in mediating virus entry, it becomes a potential target for the design of antiviral drugs against COVID-19. Here, we tested the antiviral activity of berbamine hydrochloride, a bis-benzylisoquinoline alkaloid, against SARS-CoV-2 infection. We found that berbamine hydrochloride could efficiently inhibit SARS-CoV-2 infection in different cell lines. Further experiments showed berbamine hydrochloride inhibits SARS-CoV-2 infection by targeting the viral entry into host cells. Moreover, berbamine hydrochloride and other bis-benzylisoquinoline alkaloids could potently inhibit S-mediated cell-cell fusion. Furthermore, molecular docking results implied that the berbamine hydrochloride could bind to the post fusion core of SARS-CoV-2 S2 subunit. Therefore, berbamine hydrochloride may represent a potential efficient antiviral agent against SARS-CoV-2 infection.     

Single-layered fluorinated graphene nanopores for H2/CH4 and H2/CO2 separation with high efficiency and selectivity

In response to the COVID-19 pandemic, and the lack of effective and safe antivirals against it, we adopted a new approach in which food supplements with vital antiviral characteristics, low toxicity, and fast excretion have been targeted. The structures and chemical properties of the food supplements were compared to the promising antivirals against SARS-COV-2. Our goal was to exploit the food supplements to mimic the topical antivirals’ functions but circumventing their severe side effects, which has limited the necessary dosage needed to exhibit the desired antiviral activity. On this line, after a comparative structural analysis of the chemicals mentioned above, and investigation of their potential mechanisms of action, we selected caffeine and some compounds of the vitamin B family and further applied molecular modeling techniques to evaluate their interactions with the RDB domain of the Spike protein of SARS-CoV-2 (SC2Spike) and its corresponding binding site on human ACE-2 (HssACE2). Our results pointed to vitamins B1 and B6 in the neutral form as potential binders to the HssACE2 RDB binding pocket that might be able to impair the SARS-CoV-2 mechanism of cell invasion, qualifying as potential leads for experimental investigation against COVID-19.