PINK1 and Alzheimer disease: It is important to note, that several studies of human brain biopsies have found reduced PINK1 levels in brains with AD pathology [16,23,24] For example, Vaillant-Beuchot and his team described decreased levels of PINK1 in Alzheimer brain biopsies compared to control samples, but in the same paper, they presented increased levels of PINK1 in APPswe cells compared to control cells [24].