Background
Glia mediated neuroinflammation and degeneration of inhibitory GABAergic interneurons are some of the hall marks of pyrethroid neurotoxicity. Here we investigated the sex specific responses of inflammatory cytokines, microglia, astrocyte and parvalbumin positive inhibitory GABAergic interneurons to λ-cyhalothrin (LCT) exposures in rats.
Conclusion
LCT specifically induced inflammation and disrupted GABAergic interneurons' integrities via activation of microglia and reactive astrogliosis and such effects are dose-dependent and sexually dimorphic.
Methods
Equal numbers of male and female rats were given oral corn oil, 2 mg/kg.bw and 4 mg/kg.bw of LCT for fourteen days. They were euthanized on day 15, brains were excised and hippocampus (n = 5/group) isolated for interleukin 1 beta (IL-1β) and tumor necrotic factor alpha (TNF-α) analysis. The remaining brains (n = 3/group) were processed for Ionized calcium binding adaptor molecule 1 (Iba1), glial fibrillary acidic protein (GFAP) and parvalbumin (PV) distribution in the hippocampus. All quantitative data was subjected to one way analysis of variance (ANOVA).
Results
LCT caused sex and dose dependent increase in IL-1β and TNF-α concentrations, distribution of microglia (Iba1+) and astrocytes (GFAP+), and reduction of PV + GABAergic interneurons. These effects were greater in males compared to females, and dose-dependent in both sexes.