Data herein reported indicate that one month of T1DM induced by STZ in female rats is able to decrease memory abilities, evaluated by the NOR test and that, in the hippocampus, this effect is associated with neuroinflammation (i.e., an increase in the levels of IL-1β and IL-6) and aberrant synaptogenesis (i.e., decrease in the levels of synaptophysin, synapsin and syntaxin) but not with oxidative stress, measured by TBARS levels and as confirmed by the lack of alteration in the mitochondrial functionality, measured by OXPHOS levels. The gene discussed is SYP; the disease is type 1 diabetes mellitus.