VGF and Alzheimer disease: The neuronal signaling cluster contained multiple well-established synaptic markers such as neuronal pentraxin 1 and 2 (NPTX1; NPTX2) and the neuronal pentraxin receptor (NPTXR) as well as VGF (nonacronymic), which were downregulated in DEM-AD compared to CU and MCI-AD.