TY - JOUR
T1 - Gender related differences in the oxidative stress response to PCB exposure in an endangered goodeid fish (Girardinichthys viviparus)
AU - Vega-López, Armando
AU - Galar-Martínez, Marcela
AU - Jiménez-Orozco, Fausto Alejandro
AU - García-Latorre, Ethel
AU - Domínguez-López, Maria Lilia
N1 - Funding Information:
We are grateful to the SEMARNAT, Dirección General de Vida Silvestre (Mexico) for authorizing the collection of parent specimens and most particularly to the biologists Gabriel Solano and Dolores Morales. Our thanks also to the staff of the Lago de Texcoco Project, CNA, in particular MVZ Fernando Núñez for the support in the field. This study was financed by the Instituto Politécnico Nacional, CGPI code 20041154. Galar-Martínez, M; Domínguez-López M.L. and E. García-Latorre are fellows of COFAA-IPN, EDI and SNI.
PY - 2007/4
Y1 - 2007/4
N2 - Polychlorinated biphenyls (PCBs) are persistent xenobiotics within aquatic environments, which elicit diverse toxic effects such as induction of oxidative stress. Despite numerous earlier studies, no detailed information exists on the toxic response by different sexes in fish. The aim of this study was to determine sex-linked differences in oxidative stress response and antioxidant defenses in Girardinichthys viviparus, an endangered fish endemic to Mexico, when exposed to sub-lethal concentrations of waterborne PCBs. The biological markers evaluated were lipid peroxidation (LPOX), superoxide dismutase (SOD) and catalase (CAT) activity. Adult eight-month-old specimens born in the laboratory were exposed to 1/2 of the LC0 (0.92 mg PCBs/L) in semi-hard synthetic water and sacrificed on days 1, 2, 4, 8 and 16 for biomarker assays. Sex-linked differences were observed in the control fish with respect to all three factors assayed. PCBs elicited significant (p < 0.01) time- and sex-dependent LPOX levels which were higher in the case of males. In PCB-treated G. viviparus, SOD activity was depressed in both sexes and appears to return to pre-exposure levels after 16 days in males only. In contrast, CAT was significantly induced (p < 0.01) in both sexes. This enzyme may be responsible for balancing oxidative stress and antioxidant defenses under experimental conditions. PCBs at sub-lethal concentrations are hazardous to both sexes of G. viviparus since these compounds are able to induce liver LPOX and changes in the antioxidant defense activities. The relationship between these biomarkers and cytochrome P450 and CYP1A induction is also discussed.
AB - Polychlorinated biphenyls (PCBs) are persistent xenobiotics within aquatic environments, which elicit diverse toxic effects such as induction of oxidative stress. Despite numerous earlier studies, no detailed information exists on the toxic response by different sexes in fish. The aim of this study was to determine sex-linked differences in oxidative stress response and antioxidant defenses in Girardinichthys viviparus, an endangered fish endemic to Mexico, when exposed to sub-lethal concentrations of waterborne PCBs. The biological markers evaluated were lipid peroxidation (LPOX), superoxide dismutase (SOD) and catalase (CAT) activity. Adult eight-month-old specimens born in the laboratory were exposed to 1/2 of the LC0 (0.92 mg PCBs/L) in semi-hard synthetic water and sacrificed on days 1, 2, 4, 8 and 16 for biomarker assays. Sex-linked differences were observed in the control fish with respect to all three factors assayed. PCBs elicited significant (p < 0.01) time- and sex-dependent LPOX levels which were higher in the case of males. In PCB-treated G. viviparus, SOD activity was depressed in both sexes and appears to return to pre-exposure levels after 16 days in males only. In contrast, CAT was significantly induced (p < 0.01) in both sexes. This enzyme may be responsible for balancing oxidative stress and antioxidant defenses under experimental conditions. PCBs at sub-lethal concentrations are hazardous to both sexes of G. viviparus since these compounds are able to induce liver LPOX and changes in the antioxidant defense activities. The relationship between these biomarkers and cytochrome P450 and CYP1A induction is also discussed.
KW - Catalase
KW - Endangered fish
KW - Girardinichthys viviparus
KW - Goodeid fish
KW - Lipid peroxidation
KW - PCBs
KW - ROS
KW - Sex-linked differences
KW - Superoxide dismutase
UR - http://www.scopus.com/inward/record.url?scp=33847395460&partnerID=8YFLogxK
U2 - 10.1016/j.cbpa.2006.04.022
DO - 10.1016/j.cbpa.2006.04.022
M3 - Artículo
C2 - 16829149
SN - 1095-6433
VL - 146
SP - 672
EP - 678
JO - Comparative Biochemistry and Physiology -Part A : Molecular and Integrative Physiology
JF - Comparative Biochemistry and Physiology -Part A : Molecular and Integrative Physiology
IS - 4
ER -