Fenvalerate-induced macromolecular changes in the catfish, Clarias batrachus

Area of Science:

• Environmental Toxicology
• Biochemistry
• Aquatic Biology

Background:

• Fenvalerate is a widely used synthetic pyrethroid insecticide.
• Pesticides can pose risks to aquatic ecosystems and non-target organisms.
• Understanding the biochemical effects of pesticides on fish is crucial for environmental risk assessment.

Purpose of the Study:

• To investigate the impact of sublethal fenvalerate concentrations on nucleic acid and protein levels in Clarias batrachus.
• To determine tissue-specific responses (gill and kidney) to fenvalerate exposure.
• To elucidate the molecular mechanisms underlying fenvalerate toxicity in fish.

Main Methods:

• Exposure of Clarias batrachus to sublethal fenvalerate concentrations.
• Quantification of DNA, RNA, and protein content in gill and kidney tissues.
• Calculation of the RNA/DNA ratio to assess cellular growth and stress responses.

Main Results:

• Fenvalerate significantly reduced DNA content in fish gills but showed no significant effect on kidney DNA.
• A substantial decrease in RNA and protein content was observed in both gill and kidney tissues.
• The RNA/DNA ratio remained unchanged, indicating a specific impact on protein synthesis rather than overall cellular proliferation.

Conclusions:

• Fenvalerate exhibits tissue-specific toxicity, affecting DNA content differently in gills versus kidneys.
• The observed reduction in protein and RNA suggests that fenvalerate interferes with protein synthesis pathways.
• The unchanged RNA/DNA ratio implies that fenvalerate's effect on protein levels may be due to reduced translation efficiency of messenger RNA (mRNA).