Sulforaphane is a reversible covalent inhibitor of 3-chymotrypsin-like protease of SARS-CoV-2.

The ongoing pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has posed a major public health threat worldwide and emphasizes an urgent need for effective therapeutics. Recently, Ordonez et al. identified sulforaphane (SFN) as a novel coronavirus inhibitor both in vitro and in mice, but the mechanism of action remains elusive. In this study, we independently discovered SFN for its inhibitory effect against SARS-CoV-2 using a target-based screening approach, identifying the viral 3-chymotrypsin-like protease (3CLpro ) as a target of SFN. Mechanistically, SFN inhibits 3CLpro in a reversible, mixed-type manner. Moreover, enzymatic kinetics studies reveal that SFN is a slow-binding inhibitor, following a two-step interaction. Initially, an encounter complex forms by specific binding of SFN to the active pocket of 3CLpro ; subsequently, the isothiocyanate group of SFN as "warhead" reacts covalently to the catalytic cysteine in a slower velocity, stabilizing the SFN-3CLpro complex. Our study has identified a new lead of the covalent 3CLpro inhibitors which has potential to be developed as a therapeutic agent to treat SARS-CoV-2 infection.

Bioactivity-Guided Separation of Anti-Cholinesterase Alkaloids from Uncaria rhynchophlly (Miq.) Miq. Ex Havil Based on HSCCC Coupled with Molecular Docking.

As an important source of cholinesterase inhibitors, alkaloids in natural products have high potential value in terms of exerting pharmacological activities. In this study, a strategy for targeted preparation of cholinesterase inhibitors in Uncaria rhynchophlly (Miq.) Miq. ex Havil (UR) by high-speed counter-current chromatography was provided. In the method, a two-phase polar solvent system composed of ethyl acetate/n-butanol/water (1:4:5, v/v/v) was used, which isolated five alkaloids from the UR extract for the first time. All alkaloids were identified by HR-ESI-MS and NMR as 7-epi-javaniside (1), vincosamide (2), strictosamide (3), cadambine (4), and 3α-dihydrocadambine (5). The poorly resolved compounds 2 and 3 were separated by preparative HPLC (prep-HPLC). Among them, compounds 1, 4, and 5 were firstly obtained from UR. The purity of these plant isolates was 98.8%, 98.7%, 99.2%, 95.7%, and 98.5%, respectively. Compounds 1-5 exhibited an inhibitory effect on acetyl-cholinesterase and butyryl-cholinesterase with an IC50 from 1.47 to 23.24 µg/mL and 1.01 to 18.24 µg/mL. Molecular docking and inhibitory activities indicated that compound 1 showed stronger inhibitory activity on acetyl-cholinesterase and butyryl-cholinesterase.

Development of SARS-CoV-2 entry antivirals.

The global outbreak of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) threatened human health and public safety. The development of anti-SARS-CoV-2 therapies have been essential to curb the spread of SARS-CoV-2. Particularly, antivirals targeting viral entry have become an attractive target for the development of anti-SARS-CoV-2 therapies. In this review, we elucidate the mechanism of SARS-CoV-2 viral entry and summarize the development of antiviral inhibitors targeting viral entry. Moreover, we speculate upon future directions toward more potent inhibitors of SARS-CoV-2 entry. This study is expected to provide novel insights for the efficient discovery of promising candidate drugs against the entry of SARS-CoV-2, and contribute to the development of broad-spectrum anti-coronavirus drugs.

Material basis and pharmacodynamic mechanism of YangshenDingzhi granules in the intervention of viral pneumonia: Based on serum pharmacochemistry and network pharmacology.

BACKGROUND: YangshenDingzhi granules (YSDZ) are clinically effective in preventing and treating COVID-19. The present study elucidates the underlying mechanism of YSDZ intervention in viral pneumonia by employing serum pharmacochemistry and network pharmacology. METHODS: The chemical constituents of YSDZ in the blood were examined using ultra-performance liquid chromatography-quadrupole/orbitrap high-resolution mass spectrometry (UPLC-Q-Exactive Orbitrap MS). Potential protein targets were obtained from the SwissTargetPrediction database, and the target genes associated with viral pneumonia were identified using GeneCards, DisGeNET, and Online Mendelian Inheritance in Man (OMIM) databases. The intersection of blood component-related targets and disease-related targets was determined using Venny 2.1. Protein-protein interaction networks were constructed using the STRING database. The Metascape database was employed to perform enrichment analyses of Gene Ontology (GO) functions and Kyoto Encyclopedia of Genes and Genomes (KEGG) signaling pathways for the targets, while the Cytoscape 3.9.1 software was utilized to construct drug-component-disease-target-pathway networks. Further, in vitro and in vivo experiments were performed to establish the therapeutic effectiveness of YSDZ against viral pneumonia. RESULTS: Fifteen compounds and 124 targets linked to viral pneumonia were detected in serum. Among these, MAPK1, MAPK3, AKT1, EGFR, and TNF play significant roles. In vitro tests revealed that the medicated serum suppressed the replication of H1N1, RSV, and SARS-CoV-2 replicon. Further, in vivo testing analysis shows that YSDZ decreases the viral load in the lungs of mice infected with RSV and H1N1. CONCLUSION: The chemical constituents of YSDZ in the blood may elicit therapeutic effects against viral pneumonia by targeting multiple proteins and pathways.

An orally active entry inhibitor of influenza A viruses protects mice and synergizes with oseltamivir and baloxavir marboxil.

Seasonal or pandemic illness caused by influenza A viruses (IAVs) is a major public health concern due to the high morbidity and notable mortality. Although there are several approved drugs targeting different mechanisms, the emergence of drug resistance calls for new drug candidates that can be used alone or in combinations. Small-molecule IAV entry inhibitor, ING-1466, binds to hemagglutinin (HA) and blocks HA-mediated viral infection. Here, we show that this inhibitor demonstrates preventive and therapeutic effects in a mouse model of IAV with substantial improvement in the survival rate. When administered orally it elicits a therapeutic effect in mice, even after the well-established infection. Moreover, the combination of ING-1466 with oseltamivir phosphate or baloxavir marboxil enhances the therapeutic effect in a synergistic manner. Overall, ING-1466 has excellent oral bioavailability and in vitro absorption, distribution, metabolism, excretion, and toxicity profile, suggesting that it can be developed for monotherapy or combination therapy for the treatment of IAV infections.

Rapid screening and characterization of 2-(2-phenylethyl)chromones in agarwood by UHPLC-Q-Exactive Orbitrap-MS.

The purpose of this study is to develop an improved comprehensive data filtering strategy, which was implemented primarily through the Microsoft Office platform's Excel software for rapid screening of potential 2-(2-phenylethyl)chromone (PEC) monomers and their dimers (PEC dimers) obtained from agarwood. A total of 108 PEC monomers and 30 PEC dimers in agarwood were characterized. In conclusion, the results obtained in this work could provide useful information for the future utilization of agarwood. In particular, it is the first time to conduct an in-depth analysis of the MS/MS fragmentation behavior of a large number of PEC monomers and PEC dimers, including the identification of substituent positions of them. The proposed data filtering strategy could improve the comprehensive characterization efficiency of complex components in spices.

Allopregnanolone targets nucleoprotein as a novel influenza virus inhibitor.

Influenza A virus (IAV) poses a global public health concern and remains an imminent threat to human health. Emerging antiviral resistance to the currently approved influenza drugs emphasizes the urgent need for new therapeutic entities against IAV. Allopregnanolone (ALLO) is a natural product that has been approved as an antidepressant drug. In the present study, we repurposed ALLO as a novel inhibitor against IAVs. Mechanistic studies demonstrated that ALLO inhibited virus replication by interfering with the nucleus translocation of viral nucleoprotein (NP). In addition, ALLO showed significant synergistic activity with compound 16, a hemagglutinin inhibitor of IAVs. In summary, we have identified ALLO as a novel influenza virus inhibitor targeting NP, providing a promising candidate that deserves further investigation as a useful anti-influenza strategy in the future.

Discovery of Biomarkers and Potential Mechanisms of Agarwood Incense Smoke Intervention by Untargeted Metabolomics and Network Pharmacology.

BACKGROUND: Agarwood, as a traditional Chinese medicine, has great potential value for the treatment of tranquilization. However, its potential mechanisms and biomarkers are still unclear. METHODS: In this study, ultra-high performance liquid chromatography-quadrupole-Exactive Orbitrap mass spectrometry (UHPLC-Q-Exactive Orbitrap-MS)-based metabonomics was adopted to discover the potential biomarkers in mice after agarwood incense smoke (AIS) intervention. Furthermore, the chemical components in agarwood were identified based on UHPLC-Q-Exactive Orbitrap-MS. The global view of potential compound-target-pathway (C-T-B) network was constructed through network pharmacology to understand the potentially material basis of biomarkers. RESULTS: Metabolic profiling indicated that the metabolic changed significantly in mice serum after AIS intervention. A total of 18 potential biomarkers closely related to insomnia and emotional disease were identified, mainly involving in tryptophan metabolism, arginine and proline metabolism, cysteine and methionine metabolism and steroid hormone biosynthesis pathways. A total of 138 components in agarwood were identified based on UHPLC-Q-Exactive Orbitrap-MS. The results showed that mainly compounds such as flidersia type 2-(2-phenylethyl) chromones (FTPECs) and sesquiterpenes exerted good docking abilities with key target proteins, which were involved in multiple diseases including depression and hypnosis. CONCLUSION: In conclusion, this study enhanced current understanding of the change of metabolic markers after AIS intervention. Meanwhile, it also confirmed the feasibility of combining metabolomics and network pharmacology to identify active components and elucidate the material basis of biomarkers and mechanisms.

Rapid screening and characterization of glucosinolates in 25 Brassicaceae tissues by UHPLC-Q-exactive orbitrap-MS.

Glucosinolates (GSLs) are secondary plant metabolites that occur mainly in the Brassicaceae plants, which are desirable compounds in human foods due to their diverse biological activities. In this study, we developed an integrated data filtering and identification strategy to characterize the GSLs. An in-depth GSLs profiling was performed on 25 commonly Brassicaceae tissues in Jinan, China. By comparison with the reference standards and previous researches, we tentatively identified 47 GSLs including 8 unknown ones. The GSLs profiles of 25 Brassicaceae tissues were established, and 11 markers of GSLs could be used to distinguish the Brassica and Raphanus. This approach enables accurately characterization the GSLs of Brassicaceae tissues, and demonstrates the potential of GSLs profiles for Brassicaceae species discrimination.

Benzofuran derivatives with nerve growth factor-potentiating activity from Phellinus ribis.

Three new benzofuran derivatives, namely ribisin E (1) ribisin F (2) along with ribisin G (3) were isolated from the MeOH extract of the fruiting bodies of Phellinus ribis. Their structures were elucidated based on the NMR analysis. Furthermore, the absolute configuration of ribisin E (1) and ribisin G (3) were deduced by the CD calculations, and the absolute configuration of ribisin F (2) was determined by comparing its CD spectrum and specific rotation with the data of known analogues. All compounds (1-3) exhibited the activity of promoting neurite outgrowth in nerve growth factor (NGF)-ediated PC 12 cell at concentrations ranging from 1 to 30 µM.