Animal model studies of PD using DPP4 inhibitors (sitagliptin and liraglutide) reported their beneficial effects, including improved motor function, reduced memory deficits, reduced dopaminergic degeneration, reduced oxidative stress and neuroinflammatory markers, attenuated apoptosis, and increased neurogenesis [382,383,384,385,386,387]. This evidence concerns the gene DPP4 and Parkinson disease.