GLP1R and obesity due to melanocortin 4 receptor deficiency: It has triggered a frenzy of research and development of small molecule GLP-1R agonists for various conditions, such as obesity, diabetes, Metabolic dysfunction-associated steatotic liver disease (MASLD)/Nonalcoholic fatty liver disease (NAFLD), Metabolic dysfunction-associated steatohepatitis (MASH)/Nonalcoholic steatohepatitis (NASH) [3], metabolic disorders, Alzheimer’s disease, Parkinson’s disease, cardiovascular disease and other drugs [4,5].