Environmental polychlorinated biphenyl exposure and cytochromes P450 in raccoons (<i>Procyon lotor</i>)

Smith, Philip; Bandiera, Stelvio M.; Skipper, Sherry L.; Johnson, Kevin A.; McMurry, Scott T.

doi:10.1002/etc.5620220224

Cited by 4 publications

(2 citation statements)

References 27 publications

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“…For example, juvenile summer flounder from Delaware and North Carolina, USA, exhibited different predictive relationships between RNA:DNA ratio and body growth rates [15]. Smith et al [16] used three separate measures of hepatic cytochrome P450 (P450) induction as biomarkers of poly‐chlorinated biphenyl (PCB) exposure in racoons. Those authors found significant linear relationships between the various biomarkers and PCB body residues with pentoxyresorufin O‐deethylase (PROD) activity, with P4501A1 and P4501A2 levels most closely related to PCB exposure.…”

Section: Why Biomarkers Are Not Useful Predictorsmentioning

confidence: 99%

The use and misuse of biomarkers in ecotoxicology

Forbes

Palmqvist

Bach

2006

Enviro Toxic and Chemistry

374

227

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Substantial efforts have been devoted to developing and applying biomarkers for use in ecotoxicology. These efforts have resulted partly from a desire for early warning indicators that respond before measurable effects on individuals and populations occur and partly as an aid to identifying the causes of observed population- and community-level effects. Whereas older biomarkers focused on measures of organism physiology or biochemistry, advances in molecular biology are extending the biomarker philosophy to the level of the genes (i.e., ecotoxicogenomics). However, the extent to which biomarkers are able to provide unambiguous and ecologically relevant indicators of exposure to or effects of toxicants remains highly controversial. In the present paper, we briefly discuss the application of biomarkers in ecotoxicology and ecological risk assessment, and we provide examples of how they have been applied. We conclude that although biomarkers can be helpful for gaining insight regarding the mechanisms causing observed effects of chemicals on whole-organism performance and may, in some cases, provide useful indicators of exposure, individual biomarker responses should not be expected to provide useful predictions of relevant ecological effects--and probably not even predictions of whole-organism effects. Suites of biomarkers are only likely to provide increased predictability if they can be used in a comprehensive mechanistic model that integrates them into a measure of fitness. Until this can be achieved, biomarkers may be useful for hypothesis generation in carefully controlled experiments. However, because the aims of environmental monitoring and ecological risk assessment are to detect and/or predict adverse chemical impacts on populations, communities, and ecosystems, we should be focusing our efforts on improving methods to do this directly. This will involve developing and testing models of appropriate complexity that can describe real-world systems at multiple scales.

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Section: Why Biomarkers Are Not Useful Predictorsmentioning

confidence: 99%

The use and misuse of biomarkers in ecotoxicology

Forbes

Palmqvist

Bach

2006

Enviro Toxic and Chemistry

374

227

View full text Add to dashboard Cite

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“…Overall, these CYP isoforms seem to be useful as biomarkers to determine the levels of environmental pollutants. Indeed, CYP-dependent activities, especially CYP1A1 and CYP1A2 activities, are reported to be related to PCB residue levels in wild raccoons [ 54 ]. In this study, raccoons fed commercial dog food in the laboratory for one week showed elevations in CYP concentration, EROD activity, and PROD activity.…”

Section: Discussionmentioning

confidence: 99%

Characteristics of cytochrome P450-dependent metabolism in the liver of the wild raccoon, <i>Procyon lotor</i>

Shinya

Yohannes

Ikenaka

et al. 2022

The Journal of Veterinary Medical Science

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Wildlife is exposed to a wide range of xenobiotics in the natural environment. In order to appropriately assess xenobiotic-induced toxicity in wildlife, it is necessary to understand metabolic capacities. Carnivores, in general, have low metabolic abilities, making them vulnerable to a variety of chemicals. Raccoons (Procyon lotor) in the wild have been found to have high levels of xenobiotics. However, little is known about the metabolic capacity of the cytochrome P450 (CYP) enzymes in this species. Thus, this study used liver samples to investigate the characteristics of CYP enzymes in wild raccoons. In 22 wild raccoons, CYP concentrations in hepatic microsomes were examined. To better understand the properties of CYP-dependent metabolism, in vitro metabolic activity studies were performed using ethoxyresorufin, pentoxyresorufin and testosterone as substrates. In addition, three raccoons were fed commercial dog food in the laboratory for one week, and the effects on CYP-dependent metabolism were investigated. In comparison to other mammalian species, raccoons had very low concentrations of CYP in their livers.In an in vitro enzymatic analysis, raccoons' ethoxyresorufin O-deethylase (EROD) and pentoxyresorufin O-depentylase (PROD) metabolic capacities were less than one-fifth and one-tenth of rats', respectively. These results indicate the possible high risk in raccoons if exposed to high levels of environmental xenobiotics because of their poor CYP activity. In this study, the features of CYP-dependent metabolism in wild raccoons are described for the first time.

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