GFAP and Alzheimer disease: Most importantly, tau protein dysregulation is a well-established factor in several neurodegenerative disorders such as Alzheimer ́s disease, but several other markers for neurodegeneration such as neurofilament light chain (NfL) [31], glial fibrillary acidic protein (GFAP) [32], and ubiquitin carboxy-terminal hydrolase L1 (UCH-L1) exist [33].