NRXN2 and Alzheimer disease: - reduced levels in plasma isolated NDEVs from AD patients in comparison to controls; the reduced levels correlated with cognitive loss;- the decreased levels of Neurexin-2-α, GluA4-containing Glutamate receptor and Neuroligin-1 were present up to 6-11 years before clinical diagnosis, and reduction was directly proportional to disease progression.53