SYP and early-onset autosomal dominant Alzheimer disease: In this sense, in the case of Alzheimer’s disease, it has been shown that the IL-1beta secreted by microglia cells decreases the synthesis of synaptophysin (Li et al., 2003) and that IFN-gamma can decrease the rate of synapse formation, as shown in rat-cultured sympathetic and hippocampal neurons (Kim et al., 2002).