APP and early-onset autosomal dominant Alzheimer disease: For example, in Alzheimer’s disease, the lactylation of the amyloid precursor protein (APP) at the K612 site affects its metabolic pathway, inhibits the amyloid pathway, promotes the endosomal–lysosomal degradation pathway, and reduces the production of the pathological deposition of amyloid-β (Aβ) [23].