TMEM97 and Alzheimer disease: Several σ1R and σ2R ligands, such as PRE-084, SA4503, and Rivastigmine, are showing promising anti-amnestic effects in pre-clinical studies of mild-to-moderate AD (Sałaciak and Pytka, 2022; Alhazmi and Albratty, 2022; Rountree et al., 2013).