title: Influence of two depuration periods on the activity and transcription of antioxidant enzymes in tilapia exposed to repeated doses of cylindrospermopsin under laboratory conditions.
abstract: The cyanobacterial toxin Cylindrospermopsin (CYN), a potent protein synthesis inhibitor, is increasingly being found in freshwater bodies infested by cyanobacterial blooms worldwide. Moreover, it has been reported to be implicated in human intoxications and animal mortality. Recently, the alteration of the activity and gene expression of some glutathione related enzymes in tilapias (Oreochromis niloticus) exposed to a single dose of CYN has been reported. However, little is known about the effects induced by repeated doses of this toxin in tilapias exposed by immersion and the potential reversion of these biochemical alterations after two different depuration periods (3 or 7 days). In the present study, tilapias were exposed by immersion to repeated doses of a CYN-containing culture of Aphanizomenon ovalisporum during 14 days, and then were subjected to depuration periods (3 or 7 days) in clean water in order to examine the potential reversion of the effects observed. The activity and relative mRNA expression by real-time polymerase chain reaction (PCR) of the antioxidant enzymes glutathione peroxidase (GPx) and soluble glutathione-S-transferases (sGST), and also the sGST protein abundance by Western blot analysis were evaluated in liver and kidney of fish. Results showed significant alterations in most of the parameters evaluated and their recovery after 3 days (GPx activity, sGST relative abundance) or 7 days (GPx gene expression, sGST activity). These findings not only confirm the oxidative stress effects produced in fish by cyanobacterial cells containing CYN, but also show the effectiveness of depuration processes in mitigating the CYN-containing culture toxic effects.
authors.affiliation: Area of Toxicology, Faculty of Pharmacy, University of Sevilla, C/Profesor García González 2, Sevilla 41012, Spain. victoriarios@us.es.
authors.forename: Victoria
authors.initials: V
authors.lastname: Ríos
authors.affiliation: Area of Toxicology, Faculty of Pharmacy, University of Sevilla, C/Profesor García González 2, Sevilla 41012, Spain. rguzman1@us.es.
authors.forename: Remedios
authors.initials: R
authors.lastname: Guzmán-Guillén
authors.affiliation: Area of Toxicology, Faculty of Pharmacy, University of Sevilla, C/Profesor García González 2, Sevilla 41012, Spain. imoreno@us.es.
authors.forename: Isabel M
authors.initials: IM
authors.lastname: Moreno
authors.affiliation: Area of Toxicology, Faculty of Pharmacy, University of Sevilla, C/Profesor García González 2, Sevilla 41012, Spain. anaprieto@us.es.
authors.forename: Ana I
authors.initials: AI
authors.lastname: Prieto
authors.affiliation: Area of Toxicology, Faculty of Pharmacy, University of Sevilla, C/Profesor García González 2, Sevilla 41012, Spain. mariapuerto@us.es.
authors.forename: María
authors.initials: M
authors.lastname: Puerto
authors.affiliation: Area of Toxicology, Faculty of Pharmacy, University of Sevilla, C/Profesor García González 2, Sevilla 41012, Spain. angelesjos@us.es.
authors.forename: Angeles
authors.initials: A
authors.lastname: Jos
authors.affiliation: Area of Toxicology, Faculty of Pharmacy, University of Sevilla, C/Profesor García González 2, Sevilla 41012, Spain. camean@us.es.
authors.forename: Ana M
authors.initials: AM
authors.lastname: Cameán
mesh_terms: D000470:Alkaloids / Q000633:toxicity*; D000818:Animals; D001427:Bacterial Toxins / Q000633:toxicity*; D000458:Cyanobacteria; D000087522:Cyanobacteria Toxins; D005979:Glutathione Peroxidase / Q000235:genetics / Q000378:metabolism*; D005982:Glutathione Transferase / Q000235:genetics / Q000378:metabolism*; D007668:Kidney / Q000187:drug effects / Q000201:enzymology; D008099:Liver / Q000187:drug effects / Q000201:enzymology; D008297:Male; D018384:Oxidative Stress; D012333:RNA, Messenger / Q000378:metabolism; D017210:Tilapia / Q000378:metabolism*; D014158:Transcription, Genetic; D014498:Uracil / Q000031:analogs & derivatives* / Q000633:toxicity
chemical_list: D000470:Alkaloids; D001427:Bacterial Toxins; D000087522:Cyanobacteria Toxins; D012333:RNA, Messenger; C089595:cylindrospermopsin; D014498:Uracil; D005979:Glutathione Peroxidase; D005982:Glutathione Transferase