GLP1R and Parkinson disease: It has been published recently that clinical trials using GLP-1R agonists were promising in treating AD patients with cognitive decline and brain shrinkage through liraglutide, and motor symptoms of PD patients through exendin-4 (Byetta, Bydureon), liraglutide (Victoza, Saxenda), and lixisenatide (Lyxumia, Adlyxin) (Athauda et al., 2017; Foltynie and Athauda, 2020; Holscher, 2022, 2024).