The Anthocyanin Delphinidin 3-Rutinoside Stimulates Glucagon-Like Peptide-1 Secretion in Murine GLUTag Cell Line via the Ca2+/Calmodulin-Dependent Kinase II Pathway
Fig 5
Effect of D3R on GPR signaling pathway in GLUTag cells.
(A, B, D) GLUTag cells were pre-treated with vehicle (0.1% DMSO) or (A) GPR40/120 antagonist (GW1100, 10 μM), (B) Gαs subunit antagonist (NF449, 10 μM), (D) PKA inhibitor (H-89, 10 μM) for 15 min, followed by treatment with vehicle or D3R (100 μM) for 2 h without washing out. GLP-1 levels in the medium were measured by ELISA. Secreted GLP-1 levels are expressed as the fold change of the control levels (= 1.0). (C) Cytosolic cAMP concentrations in GLUTag cells treated with vehicle (0.1% DMSO), positive control (Fos, 10 μM + IBMX, 10 μM; F/I), or D3R (50 or 100 μM) after 15 min. Values are expressed as the means ± SEM, n = 3. Values without a common letter (a, b, c, and d) are significantly different at P < 0.05 (A, B, D, Tukey-Kramer test followed by two-way ANOVA; C, Tukey-Kramer test).