Anti-inflammatory cytokine interleukin-10 (IL-10) plays a crucial role in controlling the resolution of inflammation. In this study, we aimed to assess gene expression and the level of IL-10 in the hippocampus and prefrontal cortex of rats, after a single injection of neurotoxicant trimethyltin chloride (TMT). It was shown that 4 weeks after the treatment with TMT, the level of IL-10 in the prefrontal cortex, but not in the hippocampus of TMT-treated rats, was increased. However, expression level of IL-10 mRNA was upregulated both in the hippocampus and in the prefrontal cortex 3 weeks after the injection. Concomitantly, within the same post-treatment period, the expression level of the cyclooxygenase-2 was upregulated in both brain structures, indicating the induction of neuroinflammation. Considering that TMT leads to the death of neurons mainly in the hippocampus, we assume that in contrast to the prefrontal cortex, the level of anti-inflammatory cytokine IL-10 in the hippocampus is not sufficiently increased to prevent the damaging effect of the neurotoxicant. Therefore, an exogenous increase in the level of IL-10 may be useful for the survival of neurons in conditions of neurotoxic damage to the hippocampus.
Keywords: Hippocampus; Interleukin-10; Neurodegeneration; Neuroinflammation; Prefrontal cortex; Trimethyltin chloride.