title: Chemoprotection of lipoic acid against microcystin-induced toxicosis in common carp (Cyprinus carpio, Cyprinidae).
abstract: This paper evaluated the chemoprotective effect of lipoic acid (LA) against microcystin (MC) toxicity in carp Cyprinus carpio. To determine the LA dose and the time necessary for the induction of three different classes (alpha, mu and pi) of glutathione S-transferase (GST) gene transcription, carp were i.p. injected with 40mg/kg lipoic acid solution. A group was killed 24h after the first i.p. injection (condition 1); another group received two i.p. injections with a 24h of interval between each one and was killed 48h after the first injection (condition 2) and a third group received one i.p. injection and was killed 48h latter (condition 3). Results showed that LA was effective in promoting an increase in GSTs gene transcription in liver only in the condition 2. A second experiment was done, where carp pre-treated with LA (condition 2) were gavaged twice with a 24h interval with 50μg MC/kg. Ninety-six hours after experiment beginning, carp were killed, and organs were dissected. Results of GST activity in liver and brain suggest that LA can be a useful chemoprotection agent against MC induced toxicity, stimulating detoxification through the increment of GST activity (brain) or through reversion of GST inhibition (liver).
authors.affiliation: Curso de Pós-graduação em Ciências Fisiológicas - Fisiologia Animal Comparada, Universidade Federal do Rio Grande, FURG, Cx. P. 474, CEP 96.201-900, Rio Grande, RS, Brazil.
authors.forename: Lílian L
authors.initials: LL
authors.lastname: Amado
authors.forename: Márcia L
authors.initials: ML
authors.lastname: Garcia
authors.forename: Talita C B
authors.initials: TC
authors.lastname: Pereira
authors.forename: João S
authors.initials: JS
authors.lastname: Yunes
authors.forename: Maurício R
authors.initials: MR
authors.lastname: Bogo
authors.forename: José M
authors.initials: JM
authors.lastname: Monserrat
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D001921:Brain / Q000187:drug effects / Q000201:enzymology; D002347:Carps / Q000378:metabolism; D005721:Glutamate-Cysteine Ligase / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism; D005982:Glutathione Transferase / Q000235:genetics; D007527:Isoenzymes / Q000235:genetics; D008099:Liver / Q000187:drug effects / Q000201:enzymology; D052998:Microcystins / Q000633:toxicity*; D010545:Peroxides / Q000378:metabolism; D020011:Protective Agents / Q000494:pharmacology*; D008063:Thioctic Acid / Q000494:pharmacology*; D014874:Water Pollutants, Chemical / Q000633:toxicity
chemical_list: D000975:Antioxidants; D007527:Isoenzymes; D052998:Microcystins; D010545:Peroxides; D020011:Protective Agents; D014874:Water Pollutants, Chemical; C049375:perhydroxyl radical; D008063:Thioctic Acid; D005982:Glutathione Transferase; D005721:Glutamate-Cysteine Ligase; D005978:Glutathione