Cpl207280, a novel g protein-coupled receptor 40/free fatty acid receptor 1-specific agonist, shows a favorable safety profile and exerts antidiabetic effects in type 2 diabetic animals

Abstract

G protein-coupled receptor (GPR) 40 is a free fatty acid receptor mainly expressed in pancreatic b-cells activated by medium- and long-chain fatty acids and regulating insulin secretion via an increase in cytosolic free calcium ([Ca21]i). Activation of GPR40 in pancreatic b-cells may improve glycemic control in type 2 diabetes through enhancement of glucose-stimulated insulin secretion. However, the most clinically advanced GPR40 agonist-TAK-875 (fasiglifam)-was withdrawn from phase III because of its hepatotoxicity resulting from the inhibition of pivotal bile acid transporters. Here, we present a new, potent CPL207280 agonist and compare it with fasiglifam in numerous in vitro and in vivo studies. CPL207280 showed greater potency than fasiglifam in a Ca21 influx assay with a human GPR40 protein (EC50 = 80 vs. 270 nM, respectively). At the 10 mM concentration, it showed 3.9 times greater enhancement of glucose-stimulated insulin secretion in mouse MIN6 pancreatic b-cells. In Wistar Han rats and C57BL6 mice challenged with glucose, CPL207280 stimulated 2.5 times greater insulin secretion without causing hypoglycemia at 10 mg/kg compared with fasiglifam. In three diabetic rat models, CPL207280 improved glucose tolerance and increased insulin area under the curve by 212%, 142%, and 347%, respectively. Evaluation of potential off-target activity (Safety47) and selectivity of CPL207280 (at 10 mM) did not show any significant off-target activity. We conclude that CPL207280 is a potent enhancer of glucose-stimulated insulin secretion in animal disease models with no risk of hypoglycemia at therapeutic doses. Therefore, we propose the CPL207280 compound as a compelling candidate for type 2 diabetes treatment.