Pharmacological regulation of insulin secretion in MIN6 cells through the fatty acid receptor GPR40: identification of agonist and antagonist small molecules

Abstract

1 Long chain fatty acids have recently been identified as agonists for the G protein-coupled receptors GPR40 and GPR120. Here, we present the first description of GW9508, a small-molecule agonist of the fatty acid receptors GPR40 and GPR120. In addition, we also describe the pharmacology of GW1100, a selective GPR40 antagonist. These molecules were used to further investigate the role of GPR40 in glucose-stimulated insulin secretion in the MIN6 mouse pancreatic b-cell line. 2 GW9508 and linoleic acid both stimulated intracellular Ca 2 þ mobilization in human embryonic kidney (HEK)293 cells expressing GPR40 (pEC 50 values of 7.3270.03 and 5.6570.06, respectively) or GPR120 (pEC 50 values of 5.4670.09 and 5.8970.04, respectively), but not in the parent HEK-293 cell line. 3 GW1100 dose dependently inhibited GPR40-mediated Ca 2 þ elevations stimulated by GW9508 and linoleic acid (pIC 50 values of 5.9970.03 and 5.9970.06, respectively). GW1100 had no effect on the GPR120-mediated stimulation of intracellular Ca 2 þ release produced by either GW9508 or linoleic acid. 4 GW9508 dose dependently potentiated glucose-stimulated insulin secretion in MIN6 cells, but not in primary rat or mouse islets. Furthermore, GW9508 was able to potentiate the KCl-mediated increase in insulin secretion in MIN6 cells. The effects of GW9508 on insulin secretion were reversed by GW1100, while linoleic acid-stimulated insulin secretion was partially attenuated by GW1100. 5 These results add further evidence to a link between GPR40 and the ability of fatty acids to acutely potentiate insulin secretion and demonstrate that small-molecule GPR40 agonists are glucose-sensitive insulin secretagogues.

The Free Fatty Acid Receptor G Protein-coupled Receptor 40 (GPR40) Protects from Bone Loss through Inhibition of Osteoclast Differentiation*

“…Differentiation-Using primary bone marrow macrophage cultures and the osteoclast precursor cell line RAW264.7 we confirmed the expression of GPR40 in osteoclasts and tested the effects of GW9508, a GPR40 agonist (27), on RANKL-induced osteoclastogenesis. Addition of RANKL induced the formation of giant, multinucleated TRACP-positive osteoclasts, in both wild-type and GPR40 Ϫ/Ϫ bone marrow cells.…”

Application of GPCR Structures for Modelling of Free Fatty Acid Receptors

“…Currently, five GPCRs have been identified to bind free fatty acids with a different level of specificity. The free fatty acid receptor 1 (FFA1), previously known as GPR40, binds preferably long-and medium-chain fatty acids with more than 12 carbon atoms (Briscoe et al 2006;Itoh and Hinuma. 2005).…”

Development and Characterization of a Potent Free Fatty Acid Receptor 1 (FFA1) Fluorescent Tracer

“…For these studies, in addition to parent compounds and analogues of 2 and 4, the first high-potency FFA1 agonist 12, the previous clinical candidates 13 (AMG-837) 24 and 1, and Merck's potent thiazolidinedione agonist 14 (Cmp B) 25 were selected. [23][24][25][26] Each of the selected molecules exhibited competitive binding with 4 that allowed estimation of K i binding affinity constants (Table 2). β-arrestin pEC 50 determined using BRET-β-arrestin recruitment assay.…”