USING ELECTROSHOCK TO PROBE MECHANISMS OF HERBICIDE NEUROTOXICITY AND NOVEL NEUROPROTECTIVE COMPOUNDS IN CAENORHABDITIS ELEGANS AND DROSOPHILA MELANOGASTER

The communication in the nervous system is a pharmacological balance between excitatory and inhibitory signals, and seizure behavior is one of the most common manifestations of when an imbalance occurs. Environmental toxins can cause significant disruption of excitation-inhibition balance, but while some toxins, like nerve agents, have known targets and require novel antidotes, some have unknown neurobiological mechanisms and require exploration. Of particular concern, there is little knowledge on how herbicides may affect neurological signaling. Glyphosate, the world’s most popular herbicide, was found to be in 80% of people’s urine, and since it is so prevalent, it is critical to understand its impact on both excitatory and inhibitory signaling. We used an electroshock assay developed for C. elegans to uncover evidence that glyphosate, and the commercial formula Roundup, disrupted the excitation-inhibition balance by blocking GABA-A receptors. This presented a novel hypothesis of an inhibitory neurobiological target for glyphosate. As glutamate is the major excitatory neurotransmitter in the human central nervous system, an electrophysiology assay using Drosophila was used and found that Roundup, but not glyphosate, reduced synaptic viability. This result directs attention to the undisclosed adjuvant component which may have a significant effect on synaptic transmission, though the exact mechanism requires further investigation.