title: Antioxidant properties of the mucus secreted by Laeonereis acuta (Polychaeta, Nereididae): a defense against environmental pro-oxidants?
abstract: Polychaeta species like Laeonereis acuta (Nereididae) usually secrete great amounts of mucus that wrap the animal inside. Taking into account that fungi action in the sediment and UV radiation acting on dissolved organic matter in the water produces reactive oxygen species (ROS) like hydrogen peroxide (H(2)O(2)), it was considered that the mucus secretion could represent an antioxidant defense against environmental ROS. Antioxidant enzymes (catalase-CAT; superoxide dismutase-SOD; glutathione peroxidase-GPx and glutathione-S-transferase-GST) and total antioxidant capacity (TOSC) were determined in worms and mucus secretion. Higher (p<0.05) CAT, GPx and TOSC values were registered in mucus samples respect worms, SOD activity was similar (p>0.05) in both kind of samples, and absence of GST activity was observed in mucus samples, suggesting absence of catalyzed phase II reactions. In assays conducted with hepatoma cell lines exposed to H(2)O(2), it was verified that: (1) mucus co-exposure significantly (p<0.05) lowered DNA damage induced by H(2)O(2); (2) ROS production was significantly (p<0.05) reduced when cells were exposed simultaneously with mucus samples and H(2)O(2) respect H(2)O(2) alone. It can be concluded that the mucus production contributes substantially to the antioxidant defense system of the worm against environmental ROS through the interception or degradation of H(2)O(2), peroxyl and hydroxyl radicals.
authors.affiliation: Departamento de Ciências Fisiológicas, Fundação Universidade Federal do Rio Grande (FURG), Cx. P. 474, CEP 96.201-900, Rio Grande, RS, Brasil.
authors.forename: Tarsila B
authors.initials: TB
authors.lastname: Moraes
authors.affiliation: Departamento de Ciências Fisiológicas, Fundação Universidade Federal do Rio Grande (FURG), Cx. P. 474, CEP 96.201-900, Rio Grande, RS, Brasil.
authors.forename: Josencler L
authors.initials: JL
authors.lastname: Ribas Ferreira
authors.affiliation: Departamento de Ciências Fisiológicas, Fundação Universidade Federal do Rio Grande (FURG), Cx. P. 474, CEP 96.201-900, Rio Grande, RS, Brasil; Programa de Pós-Graduação em Ciências Fisiológicas, Fisiologia Animal Comparada (FURG), Brasil.
authors.forename: Carlos E
authors.initials: CE
authors.lastname: da Rosa
authors.affiliation: Departamento de Ciências Fisiológicas, Fundação Universidade Federal do Rio Grande (FURG), Cx. P. 474, CEP 96.201-900, Rio Grande, RS, Brasil; Programa de Pós-Graduação em Ciências Fisiológicas, Fisiologia Animal Comparada (FURG), Brasil.
authors.forename: Juliana Z
authors.initials: JZ
authors.lastname: Sandrini
authors.affiliation: Departamento de Ciências Fisiológicas, Fundação Universidade Federal do Rio Grande (FURG), Cx. P. 474, CEP 96.201-900, Rio Grande, RS, Brasil; Programa de Pós-Graduação em Ciências Fisiológicas, Fisiologia Animal Comparada (FURG), Brasil.
authors.forename: Ana P
authors.initials: AP
authors.lastname: Votto
authors.affiliation: Departamento de Ciências Fisiológicas, Fundação Universidade Federal do Rio Grande (FURG), Cx. P. 474, CEP 96.201-900, Rio Grande, RS, Brasil; Programa de Pós-Graduação em Ciências Fisiológicas, Fisiologia Animal Comparada (FURG), Brasil.
authors.forename: Gilma S
authors.initials: GS
authors.lastname: Trindade
authors.affiliation: Departamento de Ciências Fisiológicas, Fundação Universidade Federal do Rio Grande (FURG), Cx. P. 474, CEP 96.201-900, Rio Grande, RS, Brasil; Programa de Pós-Graduação em Ciências Fisiológicas, Fisiologia Animal Comparada (FURG), Brasil.
authors.forename: Laura A
authors.initials: LA
authors.lastname: Geracitano
authors.affiliation: Departamento de Oceanografia (FURG), Brasil.
authors.forename: Paulo C
authors.initials: PC
authors.lastname: Abreu
authors.affiliation: Departamento de Ciências Fisiológicas, Fundação Universidade Federal do Rio Grande (FURG), Cx. P. 474, CEP 96.201-900, Rio Grande, RS, Brasil; Programa de Pós-Graduação em Ciências Fisiológicas, Fisiologia Animal Comparada (FURG), Brasil. Electronic address: jose@octopus.furg.br.
authors.forename: José M
authors.initials: JM
authors.lastname: Monserrat
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D002374:Catalase / Q000378:metabolism; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D015169:Colony Count, Microbial; D004249:DNA Damage; D004785:Environmental Pollutants / Q000633:toxicity; D005979:Glutathione Peroxidase / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000633:toxicity; D017665:Hydroxyl Radical / Q000378:metabolism; D009093:Mucus / Q000201:enzymology / Q000378:metabolism* / Q000382:microbiology; D010545:Peroxides / Q000378:metabolism; D011077:Polychaeta / Q000201:enzymology / Q000378:metabolism*; D051381:Rats; D017382:Reactive Oxygen Species / Q000633:toxicity; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D000975:Antioxidants; D004785:Environmental Pollutants; D010545:Peroxides; D017382:Reactive Oxygen Species; C049375:perhydroxyl radical; D017665:Hydroxyl Radical; D006861:Hydrogen Peroxide; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D005982:Glutathione Transferase