Expression profiling of toxicity pathway genes by real-time PCR array in cypermethrin-exposed mouse brain.

Cypermethrin, a type II pyrethroid, has been shown to exert genotoxic effects in the central nervous system of non-target species such as mouse and Drosophila. To unravel the gene expression of toxicity-related pathways in cypermethrin-exposed Swiss albino mouse brain, transcriptional profiling was carried out through pathway-focused real-time PCR arrays (DNA damage signaling, oxidative stress/antioxidants, and stress/toxicity pathways). The real-time PCR array data revealed a significant (p < 0.05) modulation in transcript levels of 61 genes involved in DNA replication and repair, apoptosis, cell cycle, oxidative stress, and toxicity pathways. Cypermethrin also produced oxidative stress in brain, as was evident by a significant (p < 0.05) elevation (66%) in lipid peroxidation and reduction of glutathione (GSH) content (10.6%) as well as catalase activity (56.7%). The results demonstrate that cypermethrin alters the expression of stress- and toxicity-related genes as well as induces oxidative stress which may lead to DNA damage. These observations also point to complex metabolic networks involved in genotoxic manifestations by cypermethrin.