FFAR1 and obesity due to melanocortin 4 receptor deficiency: Among the tested protein targets, CB1R, GLP-1, and GPR40 are obesity/T2DM related GPCRs and in the functional assays, PFF-A showed a good agonist effect at CB1R, while both the dieckol and PFF-A showed an antagonist effect at the GLP-1 receptor.