Besides, exosomes isolated from the cerebrospinal fluid and plasma of AD patients, or from the medium of neural cells expressing AD presenilin 1 mutations may mediate transcellular spread of pathogenic Aβ species, disrupt neuronal Ca2+ homeostasis, impair mitochondrial function, and induce neuronal apoptosis (Eitan et al., 2016). Here, PSEN1 is linked to Alzheimer disease.