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Using Caenorhabditis elegans for Studying Trans- and Multi-Generational Effects of Toxicants
Published on: July 29, 2019
Is there a causal association between genotoxicity and the imposex effect?
Josephine A Hagger1, Michael H Depledge, Jörg Oehlmann
1Ecotoxicology and Stress Biology Research Centre, School of Biological Sciences, University of Plymouth, Plymouth, Devon, United Kingdom. jhagger@plymouth.ac.uk
Environmental Health Perspectives
|July 5, 2006
Summary
Environmental pollutants can disrupt reproduction. This study provides the first evidence linking DNA damage to endocrine disruption, specifically tributyltin (TBT)-induced imposex in dog-whelks.
Area of Science:
- Environmental toxicology
- Reproductive biology
- Molecular toxicology
Background:
- Endocrine-disrupting chemicals (EDCs) interfere with hormone actions, impacting reproduction and development.
- EDCs can cause genetic damage, mutagenicity, and carcinogenicity.
- A direct link between endocrine disruption and DNA damage in vivo remained unproven.
Purpose of the Study:
- To provide the first evidence linking DNA damage with endocrine disruption in vivo.
- To investigate the relationship between tributyltin (TBT) exposure, imposex, and DNA damage in the dog-whelk (Nucella lapillus).
Main Methods:
- Collected 257 dog-whelks exhibiting various stages of TBT-induced imposex from southwest England.
- Assessed imposex status via physical examination.
- Quantified DNA damage (micronucleus formation) in hemocytes and performed histological examination of reproductive tissues.
- Analyzed TBT body burden and its association with imposex and abnormal growths.
Main Results:
- A strong positive correlation (r=0.935, p<0.0001) was found between the degree of imposex and DNA damage.
- Histological analysis revealed hyperplastic growths in the vas deferens and penis of affected snails.
- A significant association existed between TBT body burden and the prevalence of abnormal growths.
Conclusions:
- This study provides the first in vivo evidence that DNA damage is associated with endocrine disruption (imposex) caused by the environmental pollutant TBT.
- The findings support the hypothesis that EDCs can exert adverse reproductive effects partly through DNA damage pathways.
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