{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T18:13:46Z","timestamp":1790792026101,"version":"4.1.0"},"reference-count":36,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2017,1,11]],"date-time":"2017-01-11T00:00:00Z","timestamp":1484092800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["U1201227"],"award-info":[{"award-number":["U1201227"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["U1301224"],"award-info":[{"award-number":["U1301224"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["81403167"],"award-info":[{"award-number":["81403167"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Scientific Research Project of College Directly Under the Guangzhou Education Bureau, China","award":["1201430183"],"award-info":[{"award-number":["1201430183"]}]},{"name":"Science and Technology Cooperation Program  of Guangdong, China","award":["2013B051000085"],"award-info":[{"award-number":["2013B051000085"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Influenza remains one of the major epidemic diseases worldwide, and rapid virus replication and collateral lung tissue damage caused by excessive pro-inflammatory host immune cell responses lead to high mortality rates. Thus, novel therapeutic agents that control influenza A virus (IAV) propagation and attenuate excessive pro-inflammatory responses are needed. Polysaccharide extract from Radix isatidis, a traditional Chinese herbal medicine, exerted potent anti-IAV activity against human seasonal influenza viruses (H1N1 and H3N2) and avian influenza viruses (H6N2 and H9N2) in vitro. The polysaccharides also significantly reduced the expression of pro-inflammatory cytokines (IL-6) and chemokines (IP-10, MIG, and CCL-5) stimulated by A\/PR\/8\/34 (H1N1) at a range of doses (7.5 mg\/mL, 15 mg\/mL, and 30 mg\/mL); however, they were only effective against progeny virus at a high dose. Similar activity was detected against inflammation induced by avian influenza virus H9N2. The polysaccharides strongly inhibited the protein expression of TLR-3 induced by PR8, suggesting that they impair the upregulation of pro-inflammatory factors induced by IAV by inhibiting activation of the TLR-3 signaling pathway. The polysaccharide extract from Radix isatidis root therefore has the potential to be used as an adjunct to antiviral therapy for the treatment of IAV infection.<\/jats:p>","DOI":"10.3390\/molecules22010116","type":"journal-article","created":{"date-parts":[[2017,1,11]],"date-time":"2017-01-11T10:36:49Z","timestamp":1484131009000},"page":"116","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":84,"title":["Radix isatidis Polysaccharides Inhibit Influenza a Virus and Influenza A Virus-Induced Inflammation via Suppression of Host TLR3 Signaling In Vitro"],"prefix":"10.3390","volume":"22","author":[{"given":"Zhengtu","family":"Li","sequence":"first","affiliation":[{"name":"State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, (Guangzhou Medical University), Guangzhou 510120, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Li","family":"Li","sequence":"additional","affiliation":[{"name":"The First Hospital of Yulin, Yuxi Da Dao Road, Yulin 719000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hongxia","family":"Zhou","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, (Guangzhou Medical University), Guangzhou 510120, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lijuan","family":"Zeng","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, (Guangzhou Medical University), Guangzhou 510120, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tingting","family":"Chen","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, (Guangzhou Medical University), Guangzhou 510120, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qiaolian","family":"Chen","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, (Guangzhou Medical University), Guangzhou 510120, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Beixian","family":"Zhou","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, (Guangzhou Medical University), Guangzhou 510120, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yutao","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, (Guangzhou Medical University), Guangzhou 510120, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qiaoyan","family":"Chen","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Hospital of Traditional Chinese Medicine, Guangzhou University of Traditinal Chinese Medicine, Guangzhou 510180, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4836-9881","authenticated-orcid":false,"given":"Ping","family":"Hu","sequence":"additional","affiliation":[{"name":"Shanghai Key Laboratory of Functional Materials Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zifeng","family":"Yang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, (Guangzhou Medical University), Guangzhou 510120, China"},{"name":"Macau University of Science and Technology, AvenidaWai Long, Taipa, Macau 519020, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2017,1,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"258","DOI":"10.1038\/mi.2012.2","article-title":"Essential role of IL-6 in protection against H1N1 influenza virus by promoting neutrophil survival in the lung","volume":"5","author":"Dienz","year":"2012","journal-title":"Mucosal Immunol."},{"key":"ref_2","first-page":"3238","article-title":"Clinical characteristics of human infection with a novel avian-origin influenza a(H10N8) virus","volume":"127","author":"Zhang","year":"2014","journal-title":"Chin. 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