Overall, the observed negative correlation between the enzyme activity and protein levels of ChAT may suggest that higher ChAT protein levels in CSF of AD patients is a sign of an unsuccessful compensatory mechanism to recover the reduced ACh in synapses, and/or to dampen hyperactivity of astroglial cells (Darreh-Shori et al., 2013; Vijayaraghavan et al., 2013). This evidence concerns the gene CHAT and Alzheimer disease.