In addition to improving hippocampal function in animals with central STZ-induced neurotoxicity, exenatide treatment improves hippocampal-dependent spatial memory in rats made insulin resistant with a high fructose diet (Gad et al., 2016) and in a mouse model of peripheral STZ-induced diabetes (Huang et al., 2012; Gumuslu et al., 2016). The gene discussed is INS; the disease is diabetes mellitus.