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Flaviviruses are single-stranded RNA viruses predominantly transmitted by the widely distributed Aedes mosquitoes in nature. As important human pathogens, the geographic reach of Flaviviruses and their threats to public health are increasing, but there is currently no approved specific drug for treatment. In recent years, the development of peptide antivirals has gained much attention. Natural host defense peptides which uniquely evolved to protect the hosts have been shown to have antiviral properties. In this study, we firstly collected the venom of the Alopecosa nagpag spider from Shangri-La County, Yunnan Province. A defense peptide named Av-LCTX-An1a (Antiviral-Lycotoxin-An1a) was identified from the spider venom, and its anti-dengue serotype-2 virus (DENV2) activity was verified in vitro. Moreover, a real-time fluorescence-based protease inhibition assay showed that An1a functions as a DENV2 NS2B-NS3 protease inhibitor. Furthermore, we also found that An1a restricts zika virus (ZIKV) infection by inhibiting the ZIKV NS2B-NS3 protease. Together, our findings not only demonstrate that An1a might be a candidate for anti-flavivirus drug but also indicate that spider venom is a potential resource library rich in antiviral precursor molecules.
Mengyao Ji; Tengyu Zhu; Meichen Xing; Ning Luan; James Mwangi; Xiuwen Yan; Guoxiang Mo; Mingqiang Rong; Bowen Li; Ren Lai; Lin Jin. An Antiviral Peptide from Alopecosa nagpag Spider Targets NS2B-NS3 Protease of Flaviviruses. Toxins 2019, 11, 584 .
AMA StyleMengyao Ji, Tengyu Zhu, Meichen Xing, Ning Luan, James Mwangi, Xiuwen Yan, Guoxiang Mo, Mingqiang Rong, Bowen Li, Ren Lai, Lin Jin. An Antiviral Peptide from Alopecosa nagpag Spider Targets NS2B-NS3 Protease of Flaviviruses. Toxins. 2019; 11 (10):584.
Chicago/Turabian StyleMengyao Ji; Tengyu Zhu; Meichen Xing; Ning Luan; James Mwangi; Xiuwen Yan; Guoxiang Mo; Mingqiang Rong; Bowen Li; Ren Lai; Lin Jin. 2019. "An Antiviral Peptide from Alopecosa nagpag Spider Targets NS2B-NS3 Protease of Flaviviruses." Toxins 11, no. 10: 584.
Spiders are the most successful insect predators given that they use their venom containing insecticidal peptides as biochemical weapons for preying. Due to the high specificity and potency of peptidic toxins, discoveries of insecticidal toxins from spider venom have provided an opportunity to obtain natural compounds for agricultural applications without affecting human health. In this study, a novel insecticidal toxin (μ-NPTX-Nc1a) was identified and characterized from the venom of Nephila clavata. Its primary sequence is GCNPDCTGIQCGWPRCPGGQNPVMDKCVSCCPFCPPKSAQG which was determined by automated Edman degradation, cDNA cloning, and MS/MS analysis. BLAST search indicated that Nc1a shows no similarity with known peptides or proteins, indicating that Nc1a belongs to a novel family of insecticidal peptide. Nc1a displayed inhibitory effects on NaV and KV channels in cockroach dorsal unpaired median neurons. The median lethal dose (LD50) of Nc1a on cockroach was 573 ng/g. Herein, a study that identifies a novel insecticidal toxin, which can be a potential candidate and/or template for the development of bioinsecticides, is presented.
Lin Jin; Mingqian Fang; Mengrou Chen; Chunling Zhou; Rose Ombati; Abdul Hakim; Guoxiang Mo; Ren Lai; Xiuwen Yan; Yumin Wang; Shilong Yang. An insecticidal toxin from Nephila clavata spider venom. Amino Acids 2017, 49, 1237 -1245.
AMA StyleLin Jin, Mingqian Fang, Mengrou Chen, Chunling Zhou, Rose Ombati, Abdul Hakim, Guoxiang Mo, Ren Lai, Xiuwen Yan, Yumin Wang, Shilong Yang. An insecticidal toxin from Nephila clavata spider venom. Amino Acids. 2017; 49 (7):1237-1245.
Chicago/Turabian StyleLin Jin; Mingqian Fang; Mengrou Chen; Chunling Zhou; Rose Ombati; Abdul Hakim; Guoxiang Mo; Ren Lai; Xiuwen Yan; Yumin Wang; Shilong Yang. 2017. "An insecticidal toxin from Nephila clavata spider venom." Amino Acids 49, no. 7: 1237-1245.
The present study was designed to investigate the antimalarial activity of synthetic hepcidin and its effect on cytokine secretion in mice infected with Plasmodium berghei. The mice were infected with P. berghei intravenously and treated with hepcidin according to 4-day suppression test and Rane's test. The serum levels of interleukins (IL-1β, IL-2, IL-6, IL-10, IL-12p70, and IL-17A), tumor necrosis factor-α (TNF-α), and interferon-γ (IFN-γ) in the experimental mice were determined using a cytometric bead array (CBA) kit. The survival rate of the infected mice was also registered. Additionally, the serum iron, alanine transaminase (ALT), aspartate transaminase (AST), and total bilirubin (BIL) were detected to evaluate liver functions. Hepcidin exerted direct anti-malarial function in vivo and increased survival rate in a dose-dependent manner. In addition, the secretion of T helper cell type 1 (Th1), Th2, and Th17 cytokines, TNF-α, and IFN-γ were inhibited by hepcidin. In conclusion, our results demonstrated that synthetic hepcidin exerts in vivo antimalarial activity and possesses anti-inflammatory function, which provides a basis for future design of new derivatives with ideal anti-malarial activity.
Ya-Qun Fang; Chuan-Bin Shen; Ning Luan; Hui-Min Yao; Chen-Bo Long; Ren Lai; Xiu-Wen Yan. In vivo antimalarial activity of synthetic hepcidin against Plasmodium berghei in mice. Chinese Journal of Natural Medicines 2017, 15, 161 -167.
AMA StyleYa-Qun Fang, Chuan-Bin Shen, Ning Luan, Hui-Min Yao, Chen-Bo Long, Ren Lai, Xiu-Wen Yan. In vivo antimalarial activity of synthetic hepcidin against Plasmodium berghei in mice. Chinese Journal of Natural Medicines. 2017; 15 (3):161-167.
Chicago/Turabian StyleYa-Qun Fang; Chuan-Bin Shen; Ning Luan; Hui-Min Yao; Chen-Bo Long; Ren Lai; Xiu-Wen Yan. 2017. "In vivo antimalarial activity of synthetic hepcidin against Plasmodium berghei in mice." Chinese Journal of Natural Medicines 15, no. 3: 161-167.
The present study was designed to identify immunomodulatory components from the leech salivary gland of Haemadipsa sylvestris. The Sephadex G-50, Resource(TM) S column chromatography and reverse-phase high performance liquid chromatography (RP-HPLC) were used to isolate and purify the salivary gland extracts (SGE). Structural analysis of isolated compounds was based on Edman degradation and matrix assisted laser desorption ionization time-of-flight mass spectrometer (MALDI-TOF-MS). The cDNA encoding the precursor of the compound was cloned from the cDNA library of the salivary gland of H. sylvestris. The levels of inflammatory mediators, including tumor necrosis factor-α (TNF-α), interferon γ (IFN-γ), interleukin-6 (IL-6), and monocyte chemotactic protein-1 (MCP-1) were assayed using an enzyme-linked immunosorbent assay (ELISA). The effects on cell proliferation and cell viability were observed using MTT assay. A novel neuropeptide Y (Neuropeptide Y-HS) from the leech salivary gland of H. sylvestris was purified and characterized. It was composed of 36 amino acid residues and the amino acid sequence was determined to be FLEPPERPAVFTSVEQMKSYIKALNDYYLLLGRPRF-NH2, containing an amidated C-terminus. It showed significant inhibitory effects on the production of inflammatory cytokines including TNF-α, IFN-γ, IL-6, and MCP-1. Neuropeptide Y was identified from leeches for the first time. The presence of neuropeptide Y-HS in leech salivary gland may help get blood meal from hosts and inhibit inflammation.
Wei-Hui Liu; Yan Chen; Xue-Wei Bai; Hui-Min Yao; Xu-Guang Zhang; Xiu-Wen Yan; Ren Lai. Identification and characterization of a novel neuropeptide (neuropeptide Y-HS) from leech salivary gland of Haemadipsa sylvestris. Chinese Journal of Natural Medicines 2016, 14, 677 -682.
AMA StyleWei-Hui Liu, Yan Chen, Xue-Wei Bai, Hui-Min Yao, Xu-Guang Zhang, Xiu-Wen Yan, Ren Lai. Identification and characterization of a novel neuropeptide (neuropeptide Y-HS) from leech salivary gland of Haemadipsa sylvestris. Chinese Journal of Natural Medicines. 2016; 14 (9):677-682.
Chicago/Turabian StyleWei-Hui Liu; Yan Chen; Xue-Wei Bai; Hui-Min Yao; Xu-Guang Zhang; Xiu-Wen Yan; Ren Lai. 2016. "Identification and characterization of a novel neuropeptide (neuropeptide Y-HS) from leech salivary gland of Haemadipsa sylvestris." Chinese Journal of Natural Medicines 14, no. 9: 677-682.
Ixodid ticks are well known for spreading transmitted tick-borne pathogens while being attached to their hosts for almost 1–2 weeks to obtain blood meals. Thus, they must secrete many immunosuppressant factors to combat the hosts’ immune system. In the present work, we investigated an immunosuppressant peptide of the hard tick Amblyomma variegatum. This peptide, named amregulin, is composed of 40 residues with an amino acid sequence of HLHMHGNGATQVFKPRLVLKCPNAAQLIQPGKLQRQLLLQ. A cDNA of the precursor peptide was obtained from the National Center for Biotechnology Information (NCBI, Bethesda, MD, USA). In rat splenocytes, amregulin exerts significant anti-inflammatory effects by inhibiting the secretion of inflammatory factors in vitro, such as tumor necrosis factor-alpha (TNF-α), interleukin-1 (IL-1), interleukin-8 (IL-8) and interferon-gamma (IFN-γ). In rat splenocytes, treated with amregulin, compared to lipopolysaccharide (LPS) alone, the inhibition of the above inflammatory factors was significant at all tested concentrations (2, 4 and 8 µg/mL). Amregulin shows strong free radical scavenging and antioxidant activities (5, 10 and 20 µg/mL) in vitro. Amregulin also significantly inhibits adjuvant-induced paw inflammation in mouse models in vivo. This peptide may facilitate the ticks’ successful blood feeding and may lead to host immunotolerance of the tick. These findings have important implications for the understanding of tick-host interactions and the co-evolution between ticks and the viruses that they bear.
Yufeng Tian; Wenlin Chen; Guoxiang Mo; Ran Chen; Mingqian Fang; Gabriel Yedid; Xiuwen Yan. An Immunosuppressant Peptide from the Hard Tick Amblyomma variegatum. Toxins 2016, 8, 133 .
AMA StyleYufeng Tian, Wenlin Chen, Guoxiang Mo, Ran Chen, Mingqian Fang, Gabriel Yedid, Xiuwen Yan. An Immunosuppressant Peptide from the Hard Tick Amblyomma variegatum. Toxins. 2016; 8 (5):133.
Chicago/Turabian StyleYufeng Tian; Wenlin Chen; Guoxiang Mo; Ran Chen; Mingqian Fang; Gabriel Yedid; Xiuwen Yan. 2016. "An Immunosuppressant Peptide from the Hard Tick Amblyomma variegatum." Toxins 8, no. 5: 133.