3-Deoxyglucosone Induces Glucagon-Like Peptide-1 Secretion from STC-1 Cells via Upregulating Sweet Taste Receptor Expression under Basal Conditions

Figure 4

STR is involved in 3DG-induced acute GLP-1 secretion in STC-1 cells and rats under basal conditions. STC-1 cells were incubated with 5.6 mM glucose for 1 h in the presence and absence of 300 ng/ml 3DG. (a) The protein expression levels of TAS1R2, TAS1R3, and TRPM5 were measured by western blot. (b) The protein levels of TAS1R2, TAS1R3, and TRPM5 were analyzed by ImageJ software. , (n = 3). (c) STC-1 cells were incubated for 1 h with either 0 or 300 ng/ml 3DG in the presence and absence of 5 mM lactisole under 5.6 mM glucose conditions. The GLP-1 concentration in the supernatant was measured by ELISA. The data are expressed as a percent of the untreated group. , (n = 6). (d) Saline (control) or 3DG at 50 mg/kg was administered to the fasted rats by gastric gavage for 1 h. The protein levels of TAS1R2 and TAS1R3 in the duodenum of 3DG-treated rats were measured by western blot and then were analyzed by ImageJ software. (n = 3).

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