An in vitro binucleated blocked hepatic cell technique for genotoxicity testing in fish

Area of Science:

• Environmental Toxicology
• Aquatic Toxicology
• Cell Biology

Background:

• Genotoxic insults can damage fish DNA, impacting aquatic ecosystems.
• Assessing water pollutant toxicity requires reliable in vitro methods.
• Cytokinesis-blocking techniques enhance genotoxicity assays.

Purpose of the Study:

• To develop and validate a binucleated cell method for fish hepatic cells.
• To evaluate the genotoxic effects of selenium, mercury, and methylmercury in vitro.
• To assess the risk of water pollutants using a novel fish cell assay.

Main Methods:

• Developed a binucleated cell method using cytokinesis blockade in fish hepatic cells.
• Exposed trout hepatic cells in vitro to selenium, mercury, methylmercury, and mixtures.
• Scored micronuclei frequencies in cells after a single division post-insult.

Main Results:

• Micronuclei frequencies increased dose-dependently with mercury exposure.
• Selenium (Se(IV)) mitigated mercury-induced micronuclei formation.
• Inorganic mercury showed partial methylation within trout liver cells in vitro.

Conclusions:

• The binucleated fish hepatic cell technique is effective for genotoxicity assessment.
• This method aids in evaluating risks from water pollutants like mercury and selenium.
• The assay provides insights into pollutant interactions and metabolic transformations in fish cells.