| 1. |
- Yao, Xingang, et al.
(author)
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Inhibition of dengue viral infection by diasarone-I is associated with 2'O methyltransferase of NS5
- 2018
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In: European Journal of Pharmacology. - Amsterdam : Elsevier. - 0014-2999 .- 1879-0712. ; 821, s. 11-20
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Journal article (peer-reviewed)abstract
- Dengue virus (DENV) is the most prevalent mosquito borne viral pathogen worldwide. However, antiviral drugs against this infection are not available. To identify novel anti-DENV compound from traditional Chinese medicine, we discovered the ethanol extract of Acorus tatarinowii Schott containing potent anti-DENV activity and diasarone-I was isolated from this extract. Diasarone-I has antiviral effect with half maximal effective concentration (EC50) of 4.5μM and half maximal cytotoxicity concentration (CC50) of >80μM. Time of drug addition assay suggested that this compound inhibited at RNA replication step in the DENV life cycle. Further, in silico analysis indicated that diasarone-I might act as an inhibitor of 2'O Methyltransferase of NS5. Diasarone-I has also decreased the DENV2-induced STAT1 phosphorylation and ISGs. In summary, we suggest that diasarone-I may be a 2'O Methyltransferase inhibitor and might serve as a potential candidate for the treatment of DENV2 infections. © 2017 Elsevier B.V.
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| 2. |
- Yao, Xingang, et al.
(author)
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Q63, a novel DENV2 RdRp non-nucleoside inhibitor, inhibited DENV2 replication and infection
- 2018
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In: Journal of Pharmacological Sciences. - Amsterdam : Elsevier. - 1347-8613 .- 1347-8648. ; 138:4, s. 247-256
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Journal article (peer-reviewed)abstract
- Dengue virus (DENV) annually infects 400 million people worldwide. Unfortunately, there is lack ofwidely protective vaccine or drugs against DENV. The viral RNA-dependent RNA polymerase (RdRp) ofNS5 protein is highly conserved among different DENV subtypes, thus presenting itself as an attractivetarget for drug design. In the current research, SPRi was performed to screen compounds against DENV2RdRp and 5(1H)-Quinazolinone,2-(4-bromophenyl)-2,3,4,6,7,8-hexahydro-7,7-dimethyl-1,3-diphenyl(Q63) was successfully screened out with a KD of 0.9 mM. Then, ITC and molecular docking assay wasperformed to access the binding mechanism between Q63 and DENV2 RdRp. Meanwhile, Q63 alsodecreased the intermediate dsRNA production, which was the product of RdRp. Further the antiviraleffects of Q63 were evaluated on mosquito C6/36 cells and mammalian BHK-21 cells. Q63 reduced CPEand cell toxicity effect after DENV2 infection on C6/36 and BHK-21 cells, with an EC50 of 2.08 mM. Time ofaddition assay revealed that Q63 affected the early genome RNA replication stage, including genome RNAreplication. In addition, Q63 down-regulated STAT1 phosphorylation, ISG15 and ISG54 after DENV2infection. In summary, Q63 was found to be a novel RdRp non-nucleoside inhibitor and a potential leadcompound for coping with DENV infectious disease in the future. © 2018 The Authors.
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| 3. |
- Yao, Xingang, et al.
(author)
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Tatanan A from the Acorus calamus L. root inhibited dengue virus proliferation and infections
- 2018
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In: Phytomedicine. - München : Elsevier. - 0944-7113 .- 1618-095X. ; 42, s. 258-267
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Journal article (peer-reviewed)abstract
- BACKGROUND: Acorus calamus l. (Acoraceae) is a well-known traditional Chinese medicinal plant, whose root are historically mainly used to treat neurodegenerative diseases, and for cholera treatment. This datum strongly indicates the antimicrobial activity of A. calamus.PURPOSE: Our goal is to find the active constituents of A. calamus to treat dengue virus (DENV) infections, and to study the effects and mechanisms of these active substances.METHODS: The root of A. calamus was extracted by ethanol. Mosquito larva C6/36 cells were used for DENV2 replication and transfection host. Mouse kidney fibroblast cells (BHK-21) were used as a host cell to study the infection ability of the virus. DENV2-induced cytopathic effect (CPE) and plaque assay were used to evaluate the inhibitory effect of A. calamus extracts on DENV2 infectivity inhibition. The levels of E and NS1 protein expression were measured by real-time PCR and western blot assays.RESULTS: 12 compounds were isolated from ethanol extract of A. calamus root, tatanan A showed the best anti-DENV ability among these 12 compounds, which significantly alleviated DENV2-induced CPE and cytotoxicity effects, with an EC50 of 3.9 µM. In addition, RNA replication assay further confirmed the antivirus ability of tatanan A. Time-addition assay showed that tatanan A affected the early stage of viral RNA replication, which in turn inhibited mRNA and protein levels of DENV2.CONCLUSIONS: These results demonstrated the anti-DENV2 effect of tatanan A, in inhibiting DENV2 RNA replication and infections. In summary, tatanan A was found to be a novel natural DENV inhibitor and a potential candidate for the treatment of DENV infectious disease.
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| 4. |
- Zhu, Gengzheng, et al.
(author)
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Targeting pattern-recognition receptors to discover new small molecule immune modulators
- 2018
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In: European Journal of Medicinal Chemistry. - Issy-les-Moulineaux : Elsevier Masson. - 0223-5234 .- 1768-3254. ; 144, s. 82-92
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Journal article (peer-reviewed)abstract
- Pattern recognition receptors (PRRs) are key immune receptors of the innate immune system, which recognize the conserved pathogen-associated molecular patterns (PAMPs) of the invading pathogens. Compared to the adaptive immune receptors, PRRs have three distinguishing features, viz., universal expression, fast response and recognizing many kinds of microbes. Toll-like receptors (TLRs), RIG-I-like receptors (RLRs), C-type lectin receptors (CLRs) and NOD-like receptors (NLRs) recognize viral nucleic acid/bacterial fragments and trigger anti-microbial innate immune responses. Upon recognition of their ligand species, PRRs recruit specific intracellular adaptor proteins to initiate signaling pathways culminating in the activation of nuclear factor-κB (NF-κB), mitogen-activated protein (MAP) kinases and interferon regulatory factors (IRFs) that control the transcription of genes encoding pro-inflammatory factors including type I interferon and other inflammatory cytokines, which are critical for eliminating the potential threat to the host. Here, we summarize the effects of small molecule regulators acting on signaling pathways initiated by TLR, RLR and NLR as well as their influence on innate and adaptive immune responses leading to therapy. © 2017 Elsevier Masson SAS
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