Scientists studying the roundworm Caenorhabditis elegans found that the anticonvulsant drug ethosuximide delays age-related changes and extends the animal's lifespan by inhibiting certain chemosensory neurons (Collins JJ et al. PLoS Genet. 2008;4:e1000230).
Researchers at Washington University School of Medicine in St Louis, Mo, identified genes that mediated the activity of ethosuximide. They found mutations in 2 of the genes, che-3 and osm-3; these mutations cause defects in chemosensory neurons, which in turn result in an extended lifespan. This suggests that ethosuximide extends lifespan by inhibiting the function of specific chemosensory neurons.
Hildreth CJ. Senses and Lifespan. JAMA. 2009;301(1):26. doi:10.1001/jama.2008.926