Previous studies have shown that incretin hormones, such as glucagon-like peptide-1 (GLP-1) analogues, like liraglutide (LIR), which are used in the treatment of DM, can have neuroprotective effects on AD brains by crossing the blood–brain barrier, acting as neurotrophic factors, and exerting neuroprotective effects, such neurite growth and anti-inflammation [16]. The gene discussed is GCG; the disease is Alzheimer disease.