Cardiomyocyte H9c2 cells present a valuable alternative to fish lethal testing for azoxystrobin

Area of Science:

• Environmental Toxicology
• Cell Biology
• Ecotoxicology

Background:

• Pesticide risk assessment often relies on animal testing, raising ethical concerns.
• Developing reliable in vitro alternatives is crucial for efficient and ethical ecotoxicological evaluations.
• Azoxystrobin (AZX) is a widely used fungicide with potential environmental impacts.

Purpose of the Study:

• To identify a mammalian cell line with in vitro toxicity (IC50) that accurately predicts in vivo fish toxicity (LC50) for azoxystrobin (AZX).
• To establish a reliable and ethical in vitro assay as an alternative to fish toxicity testing for pesticides.

Main Methods:

• Six mammalian and fish cell lines were exposed to azoxystrobin (AZX).
• In vitro median inhibitory concentrations (IC50) were determined after 48 and 72 hours.
• In vivo median lethal concentrations (LC50) for Sparus aurata were used for comparison.

Main Results:

• H9c2 cells demonstrated the highest sensitivity to AZX among the tested cell lines.
• The H9c2 cell-based assay accurately predicted fish toxicity, with ratios (LC50/IC50) close to 1 after 72 hours of exposure.
• A ratio of LC50,96h/IC50,48h = 0.581 and LC50,96h/IC50,72h = 0.998 indicated strong correlation.

Conclusions:

• The H9c2 cell line provides a sensitive and predictive in vitro model for azoxystrobin (AZX) toxicity.
• The H9c2 cell-based assay is a suitable and ethical alternative to conventional fish toxicity assays.
• This approach can be extended to assess the toxic effects of other pesticides.