Evaluation of toxic effects of a diet containing fish contaminated with methylmercury in rats mimicking the exposure in the Amazon riverside population

Author(s)

Grotto, Denise ^[1] ; Valentini, Juliana ^[1] ; Serpeloni, Juliana Mara ^[1] ; Ponte Monteiro, Patricia Alves ^[2] ; Latorraca, Elder Francisco ^[3] ; de Oliveira, Ricardo Santos ^[3] ; Greggi Antunes, Lusania Maria ^[1] ; Garcia, Solange Cristina ^[4] ; Barbosa, Jr., Fernando ^[1]

Affiliation

^[1] Univ Sao Paulo, Fac Ciencias Farmaceut Ribeirao Preto, Dept Anal Clin Toxicol & Bromatol, BR-14040903 Sao Paulo - Brazil

^[2] Univ Sao Paulo, Fac Med Ribeirao Preto, Dept Patol, BR-14040903 Sao Paulo - Brazil

^[3] Univ Sao Paulo, Fac Med Ribeirao Preto, Dept Cirurgia & Anat, BR-14040903 Sao Paulo - Brazil

^[4] Univ Fed Rio Grande do Sul, Dept Anal Clin, BR-90046900 Porto Alegre, RS - Brazil

• Document type: Journal article
• Source: Environmental Research; v. 111, n. 8, p. 1074-1082, NOV 2011.
• Web of Science Citations: 17

Abstract

This study was designed to evaluate the effects of a diet rich in fish contaminated with MeHg, mimicking the typical diet of the Amazon riverside population, in rats. Animals were randomly assigned to one of three groups with eight rats in each group: Group I-control, received commercial ration: Group II-received a diet rich in uncontaminated fish; Group III-received a diet rich in fish contaminated with MeHg. Treatment time was 12 weeks. Oxidative stress markers were evaluated, as well as the effects of this diet on DNA stability, systolic blood pressure (SBP), nitric oxide (NO) levels and histological damage in different tissues. There was a significant increase in SBP values in rats fed with MeHg-contaminated fish diet after the 10th week of the treatment. As far as oxidative stress biomarkers are concerned, no differences were observed in reduced glutathione and protein carbonyl levels, glutathione peroxidase, catalase, superoxide dismutase or delta-aminolevulinate dehydratase activities between the groups of animals receiving contaminated and uncontaminated fish diets. On the other hand, malondialdehyde levels increased significantly in rats fed with contaminated fish. NO levels were similar in all groups. DNA migration showed augmented in rats exposed to contaminated fish and histopathological analyses showed weak but significant leukocyte infiltration. Thus, we conclude that the MeHg-contaminated fish diet induced a slight lipid peroxidation and genotoxicity. However, these effects seem to be much less pronounced than when rats are exposed to aqueous solution containing CH(3)HgCl. Our findings support the contention that the chemical form of MeHg in fish or fish nutrients such as polyunsaturated fatty acids, Se or vitamin E could minimize the toxic effects of MeHg exposure in fish-eating communities. (C) 2011 Elsevier Inc. All rights reserved. (AU)

• FAPESP's process: 09/11102-3 - Chemical speciation of selenium and mercury in biological samples for toxicological and/or nutrional evaluation
• Grantee: Fernando Barbosa Júnior
• Support Opportunities: Regular Research Grants
• FAPESP's process: 11/07416-2 - Evaluation of sample preparation procedures for Arsenic speciation in biological samples by LC-ICP-MS
• Grantee: Fernando Barbosa Júnior
• Support Opportunities: Regular Research Grants
• FAPESP's process: 11/07498-9 - Proteomic analysis in brain and kidney of rats exposed to different forms of mercury
• Grantee: Fernando Barbosa Júnior
• Support Opportunities: Regular Research Grants
• FAPESP's process: 07/05221-4 - Evaluation of oxidative stress and nitric oxide availability in rats exposed to fish contaminated to MeHg
• Grantee: Denise Grotto
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 07/04538-4 - Gene expression profile in pharmacoresistant epilepsy in children
• Grantee: Helio Rubens Machado
• Support Opportunities: Regular Research Grants