title: Anti-influenza A virus characteristics of a fucoidan from sporophyll of Undaria pinnatifida in mice with normal and compromised immunity.
abstract: Undaria pinnatifida, an edible brown alga, contains fucoidan (FuC), a sulfated polysaccharide, that inhibited the in vitro replication of influenza A virus, and stimulated both innate and adaptive immune defense functions in virus-infected mice. In the present study, the effects of oral administration of FuC were evaluated on influenza virus infection in immunocompetent and immunocompromised mice, where the efficacy of FuC was demonstrated in reducing viral replication, decreasing weight loss and mortality, and prolonging survival. Oral FuC resulted in increased neutralizing antibody production in the mucosa and blood. In contrast, while suppressing virus yields in mice more markedly than FuC, oseltamivir significantly reduced the neutralizing antibody titers in both the mucosa and blood. In immunocompromised mice, drug-resistant viruses frequently recovered after oseltamivir treatment; no resistant viruses were isolated from FuC-treated mice. FuC could be a candidate for the development of new therapeutic options including its combination with neuraminidase inhibitors such as oseltamivir.
authors: Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan. khayashi@pha.u-toyama.ac.jp
authors: Kyoko
authors: K
authors: Hayashi
authors: Jung-Bum
authors: JB
authors: Lee
authors: Takahisa
authors: T
authors: Nakano
authors: Toshimitsu
authors: T
authors: Hayashi
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000008:administration & dosage* / Q000302:isolation & purification; D001835:Body Weight; D004195:Disease Models, Animal; D016867:Immunocompromised Host; D009980:Influenza A virus / Q000187:drug effects* / Q000502:physiology; D051379:Mice; D009975:Orthomyxoviridae; D009976:Orthomyxoviridae Infections / Q000188:drug therapy*; D053139:Oseltamivir / Q000008:administration & dosage; D011134:Polysaccharides / Q000008:administration & dosage* / Q000302:isolation & purification; D016019:Survival Analysis; D016896:Treatment Outcome; D044648:Undaria / Q000737:chemistry*; D014779:Virus Replication / Q000187:drug effects
chemical_list: D000998:Antiviral Agents; D011134:Polysaccharides; D053139:Oseltamivir; C007789:fucoidan