Developmental exposure to neurotoxic chemicals showcases significant health concerns due to the vulnerability of the developing central nervous system (CNS) and the immature brain barrier. Non–dioxin-like (NDL) PCBs are long linked to neuropsychological dysfunctions but underlying mechanisms are not fully elucidated. Previous studies with embryonic PCB-95exposure, one such NDL-PCB congener, have shown altered larval behaviors on swimming speed, thigmotaxis and in Danio rerio (zebrafish). Behavior of an organism has strong correlation with the neurotransmitter profile that especially depends on the balance between the excitatory and inhibitory processes. Therefore, we determined to study the alteration of γ -aminobutyric acid (GABA) profile with embryonic PCB-95 exposure. Embryos at 2 cell stage with intact chorions were exposed to different concentrations of PCB-95 (0.5, 0.75, 1, 3 ppm) with two controls (E2 solution and the DMSO). Exposure time was at day 3 with 7 day incubation period. At day seven (7dpf), larvae were euthanized and analyzed for GABA using a liquid chromatography/tandem mass spectrometry (LC-MS/MS). We observed, low GABA concentrations for PCB-95 treated groups, compared to the controls. Dose dependent decrease was observed in treated group. These results were further validated with zebrafish brain sections, comparing the numeric dominance of early GABA- positive cells in day 7 zebrafish larvae with treated groups to controls. In conclusion, we suggest that the prenatal PCB-95 exposure alters developmental GABA expression. Together with our previous behavioral studies, these suggest that PCB-95-induced GABA expression may alter neuronal cell pattering and migration; thus resulting in neurodevelopment disorders.

2, 2’, 3, 5’, 6 polychlorinated biphenyls (PCB-95) induce behavioral and GABAgenic neurotransmitter changes in zebrafish at early developmental exposure

256th National Meeting (2018)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.