SGLT2 Inhibition Assay: For sodium-dependent glucose transport assay, cells expressing hSGLT2 were seeded into a 96-well culture plate at a density of 5×104 cells/well in RPMI medium 1640 containing 10% fetal bovine serum. The cells were used 1 day after plating. They were incubated in pretreatment buffer (10 mM HEPES, 5 mM Tris, 140 mM choline chloride, 2 mM KCl, 1 mM CaCl2, and 1 mM MgCl2, pH 7.4) at 37 °C. for 10 min. They were then incubated in uptake buffer (10 mM HEPES, 5 mM Tris, 140 mM NaCl, 2 mM KCl, 1 mM CaCl2, 1 mM MgCl2, and 1 mM 14C-nonlabeled AMG pH 7.4) containing 14C-labeled AMG (8 μM) and the inventive compound or dimethyl sulfoxide (DMSO) vehicle at 37 °C. for 2 h. Cells were washed twice with washing buffer (pretreatment buffer containing 10 mM AMG at room temperature) and then the radioactivity was measured using a liquid scintillation counter.
SGLT1 Inhibition Assay: For sodium-dependent glucose transport assay, cells expressing hSGLT1 were seeded into a 96-well culture plate at a density of 5×104 cells/well in RPMI medium 1640 containing 10% fetal bovine serum. The cells were used 1 day after plating. They were incubated in pretreatment buffer (10 mM HEPES, 5 mM Tris, 140 mM choline chloride, 2 mM KCl, 1 mM CaCl2, and 1 mM MgCl2, pH 7.4) at 37 °C. for 10 min. They were then incubated in uptake buffer (10 mM HEPES, 5 mM Tris, 140 mM NaCl, 2 mM KCl, 1 mM CaCl2, 1 mM MgCl2, and 1 mM 14C-nonlabeled AMG pH 7.4) containing 14C-labeled (8 μM) and inhibitor or dimethyl sulfoxide (DMSO) vehicle at 37 °C. for 2 h. Cells were washed twice with washing buffer (pretreatment buffer containing 10 mM AMG at room temperature) and then the radioactivity was measured using a liquid scintillation counter.