GLP1R and type 2 diabetes mellitus: Beneficial effects of enhanced GLP‐1 signaling were shown in several PD animal models after treatment with GLP‐1 receptor agonists (GLP‐1RA), drugs currently approved in the treatment of type 2 diabetes (eg, exenatide, a synthetic form of exendin‐4, liraglutide, semaglutide, lixisenatide).86