Reduction of cytochrome P4501A with age in Atlantic tomcod from the St. Lawrence Estuary, Canada: relationship with emaciation and possible effect of contamination

Couillard, Catherine M.; Wirgin, Isaac; Lebeuf, Michel; Légaré, Benoît

doi:10.1016/j.aquatox.2004.03.012

Cited by 18 publications

(21 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Lower EROD activity in SLE tomcod compared with similarly sized tomcod from the ME or RE indicates either a lower exposure to CYP1A‐inducing contaminants or a lower capacity to respond to inducing substances. In a previous study, a posttranscriptional inhibition of EROD activity, characterized by low EROD activity relative to CYP1AmRNA levels in largesized SLE tomcod, was suggestive of cellular dysfunction and of a lower capacity to respond to inducers [7].…”

Section: Discussionmentioning

confidence: 99%

“…Based on a previous study demonstrating suppression of EROD activity in large‐sized female tomcods from the SLE [7], only large‐sized (>200 mm) female tomcods were targeted for capture. Whereas large‐sized females captured in the SLE were two to five years old, most fish captured in the RE and the ME were less than three years old.…”

Section: Methodsmentioning

confidence: 99%

“…Organochlorine contaminants were extracted from the samples, cleaned up, and quantified as described previously [7]. Briefly, liver samples (0.9–1.5 g wet wt) were dried using Na 2 SO 4 and spiked with a mixture of 13 C 12 PCBs, including non‐ ortho PCBs and 13 C 12 PCDD/Fs, and labeled OPs surrogate internal standards.…”

Section: Methodsmentioning

confidence: 99%

See 2 more Smart Citations

Low hepatic ethoxyresorufin‐o‐deethylase activity correlates with high organochlorine concentrations in Atlantic tomcod from the Canadian east coast

Couillard¹,

Lebeuf²,

Ikonomou³

et al. 2005

Enviro Toxic and Chemistry

View full text Add to dashboard Cite

A suppression of hepatic ethoxyresorufin-O-deethylase (EROD) activity was reported recently in large-sized Atlantic tomcod (Microgadus tomcod) from the St. Lawrence Estuary (SLE; QC, Canada), possibly related to chronic exposure to persistent contaminants and/or to emaciation. In the present study, hepatic concentrations of organochlorine contaminants and biological responses were measured in female tomcods from three estuaries located on the Canadian east coast: The SLE, the Miramichi (ME), and the Richibucto (RE) Rivers Estuaries (NB, Canada). Tomcods from the SLE had higher hepatic concentrations of organochlorine contaminants than tomcods from the ME and RE. For example, concentrations of polychlorinated biphenyls (PCBs, lipid wt) were 2.5 to 4 times higher, and concentrations of mirex and chlordanes were 6 times higher, in tomcods from the SLE than in tomcods from the other sites. Concentrations of polycyclic aromatic hydrocarbons (PAHs) metabolites in the bile did not differ among sites. The pattern of biological responses differed markedly between the SLE and the two other sites. Tomcods from the SLE had 1.5 times higher concentrations of DNA adducts and 2 times higher rates of hepatocellular proliferation, but 20 times lower hepatic EROD activity, than tomcods from the ME and RE. Lipid content was not correlated with EROD activity, indicating that low hepatic lipid content alone does not cause suppression of EROD activity in Atlantic tomcod. In contrast, for the three sites combined, EROD activity decreased as concentrations of PCBs increased. Within sites, hepatic PCB concentrations increased as lipid content decreased. This study supports the hypothesis that low EROD activity in SLE tomcods is related to chronic exposure to organochlorine contaminants.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Low hepatic ethoxyresorufin‐o‐deethylase activity correlates with high organochlorine concentrations in Atlantic tomcod from the Canadian east coast

Couillard¹,

Lebeuf²,

Ikonomou³

et al. 2005

Enviro Toxic and Chemistry

View full text Add to dashboard Cite

show abstract

“…Contrairement à cette attente, une diminution de l'activité d'EROD avec l'âge est observée chez les poulamons de l'ESL (COUILLARD et al, 2004b). Cette diminution est associée à une perte de condition sévère suite au fraie, causant une diminution marquée du contenu lipidique du foie et une augmentation des concentrations de BPC dans les lipides hépatiques (Figure 8).…”

Section: Interactions Entre Produits Organiques Persistants Et Conditunclassified

Utilisation des poissons pour évaluer les effets biologiques des contaminants dans l’estuaire du Saint-Laurent et le fjord du Saguenay

Couillard¹

2009

rseau

View full text Add to dashboard Cite

Les organismes aquatiques de l’estuaire du Saint-Laurent (ESL) et du fjord du Saguenay (FS) sont exposés à des mélanges complexes de composés toxiques pouvant avoir un impact sur les populations, seuls ou en interaction avec d’autres facteurs environnementaux. L’objectif de cet article est de résumer l’information sur les effets biologiques des contaminants dans l’ESL et le FS obtenue à l’aide de poissons sentinelles. Trois études de cas démontrent la complémentarité de l’information obtenue avec différentes espèces. Les études sur l’anguille d’Amérique (Anguilla rostrata) montrent comment des poissons migrateurs peuvent être un vecteur important de contamination pour les prédateurs de haut niveau trophique de l’ESL. Des lésions prénéoplasiques au foie chez les anguilles en migration, probablement liées à une exposition aux hydrocarbures aromatiques polycycliques (HAP) sur leurs aires de croissance, sont un exemple d’effet à long terme de contaminants qui ne persistent pas dans les tissus des poissons. La présence d’adduits à l’ADN a été démontrée chez les poulamons atlantiques (Microgadus tomcod) résidents dans l’ESL et permet de comparer les niveaux d’exposition aux HAP génotoxiques entre l’ESL et d’autres estuaires de la côte Atlantique. Les études sur le poulamon ont aussi révélé une interaction entre leur période de jeûne hivernal et les produits organiques persistants (POP) menant à une augmentation transitoire des concentrations de POP dans le foie et à une dysfonction hépatique. Des échantillonnages sur le terrain, couplés à des expositions en cages in situ et à des expériences en laboratoire, ont permis de mettre évidence chez des plies canadiennes (Hipoglossoides platessoides) exposées à des sédiments contaminés de la baie des Anglais, des altérations immunitaires causant une augmentation de la susceptibilité aux maladies infectieuses. Les futures études devraient poursuivre le développement de biomarqueurs pour différents groupes de contaminants et les utiliser chez des espèces de poissons clés, à des stades sensibles de leur cycle de vie, en combinant différentes approches expérimentales multistresseurs à des études de surveillance sur le terrain.Aquatic organisms in the St. Lawrence Estuary (SLE) and the Saguenay Fjord (SF) are exposed to complex mixtures of toxic compounds which can have deleterious impacts on populations, alone or in combination with other environmental factors. The purpose of this paper is to summarize information about biological effects of contaminants in the SLE and SF obtained using sentinel fish species. Three case studies demonstrate the complementary nature of the information acquired using different sentinel species. Studies in American eel (Anguilla rostrata) show how migratory fish can be an important vector of contamination for high level predators in the SLE. Preneoplastic liver lesions in migrating eels, likely related to an exposure to polycyclic aromatic hydrocarbons (PAHs) in their growing areas, are an example of a long-term effect of contaminants which do not per...

show abstract

“…As fat is mobilized, the body distribution of contaminants changes and concentrations in target tissues increases leading to an increased risk of toxicity. Further studies are needed to evaluate if hepatocellular injury is associated with impacts on growth, survival, and (or) reproduction of the SLE tomcod population (Couillard et al 2004(Couillard et al , 2005. These elevated toxic concentrations were associated with altered CYP1A activity, increased susceptibility to infectious diseases, altered acute Conceptual model of the interactions between cold water temperature, increased seasonal fluctuations in energy reserves and persistent organic pollutants (POPs) in northern Atlantic cod.…”

Section: Case Study 1 Northern Atlantic Cod: Possible Interaction Bementioning

confidence: 99%

Chemical–environment interactions affecting the risk of impacts on aquatic organisms: A review with a Canadian perspective — interactions affecting vulnerability

2008

View full text Add to dashboard Cite

show abstract

Reduction of cytochrome P4501A with age in Atlantic tomcod from the St. Lawrence Estuary, Canada: relationship with emaciation and possible effect of contamination

Cited by 18 publications

References 27 publications

Low hepatic ethoxyresorufin‐o‐deethylase activity correlates with high organochlorine concentrations in Atlantic tomcod from the Canadian east coast

Low hepatic ethoxyresorufin‐o‐deethylase activity correlates with high organochlorine concentrations in Atlantic tomcod from the Canadian east coast

Utilisation des poissons pour évaluer les effets biologiques des contaminants dans l’estuaire du Saint-Laurent et le fjord du Saguenay

Chemical–environment interactions affecting the risk of impacts on aquatic organisms: A review with a Canadian perspective — interactions affecting vulnerability

Contact Info

Product

Resources

About