Cell experiment:

Human hepatocyte HepG2 cells are cultured at 37℃, 5% CO2 in DMEM supplemented with 10% fetal bovine serum, 50 μg/mL streptomycin and 50 IU/mL penicillin. Cells are seeded in a 96-well plate (2×104 cells/well) and cultured with GPR40 agonist 4 (compound 20) in DMEM for 24 h. FGPR40 agonist 4 is measured in three independent experiments[1].

Animal experiment:

8 weeks old normal male SD rats after 1 week adaptation are fasted overnight (12 h), weighted, bled via the tail vein, and randomized into 5 groups (n=6 for each group). Rats are administrated orally with a single doses of vehicle (0.5% methylcellulose aqueous solution) or GPR40 agonist 4 (compound 20) (1, 3 and 10 mg/kg suspended in vehicle) and subsequently dosed orally with glucose aqueous solution (3 g/kg) after 60 min. Blood samples are collected immediately before drug administration (~60 min), before glucose challenge (0 min), and at 15, 30, 60 and 120 min post-dose. The blood glucose is measured by blood glucose test strips[1].

FAA1 agonist-1 is a potent free fatty acid receptor 1 (FFA1/ GPR40) agonist with a pEC50 of 7.54.

FAA1 agonist-1 (compound 20) (10 mg/kg) presents superior pharmacokinetic (PK) profiles, in particular, a high maximum concentration (Cmax=2563.52 μg/L), low clearance (CL=0.154 L/h/kg), long plasma half-life (T1/2=5.57 h) and results in a high exposure (AUC0-24h=30204.43 μg/L•h). FAA1 agonist-1 also tends to have a low risk of activating caspase-3/7[1].

Single oral administration of FAA1 agonist-1 (compound 20) robustly reduces the plasma glucose excursion and enhances insulin secretion during an oral glucose tolerance test (OGTT) in a dose-dependent manner from 1 to 10 mg/kg when FAA1 agonist-1 is dosed 60 min prior to the oral glucose challenge. The area under the curve of blood glucose (AUC0-120min) and blood insulin (AUC0-120min) reveal that the minimum effective dose of FAA1 agonist-1 is 3 mg/kg. The hyperglycemia state is also markedly improved in FAA1 agonist-1 (20 mg/kg) treated group[1].

[1]. Li Z, et al. Discovery of phenylsulfonyl acetic acid derivatives with improved efficacy and safety as potent free fatty acid receptor 1 agonists for the treatment of type 2 diabetes. Eur J Med Chem. 2017 Sep 29;138:458-479.