Exendin-4 Promotes Survival of Mouse Pancreatic β-Cell Line in Lipotoxic Conditions, through the Extracellular Signal-Related Kinase 1/2 Pathway

Figure 1

Exendin-4 inhibits apoptosis in palmitate-treated MIN6 cells. MIN6 cells were incubated in 0.5% BSA (BSA) or 0.4 mM palmitate added 0.5% BSA (PA), in the presence or absence of increasing concentrations of exendin-4 (1–500 nM) (Ex), in serum-free DMEM for 24 h. Exendin-4 was added at a concentration of 100 nM for Hoechst33258 staining and caspase-3 activity assays. (a) Cell survival was assessed by MTT assay. Cell survival results are expressed as percentage of control (cells treated with BSA alone) and represent the mean ± SE of five independent experiments. , versus BSA; , , versus PA. (b) Cell proliferation was evaluated by BrdU incorporation kit. Cell proliferation results are expressed as percentage of control (cells treated with BSA alone) and represent the mean ± SE of five independent experiments. versus BSA; , , versus PA. (c) Apoptosis was evaluated by Hoechst33258 staining. Values are expressed as percentage of apoptotic cells and represent the mean ± SE of three independent experiments. . (d) Apoptosis was assessed by caspase-3 activity assay. Values are expressed as percentage of control (cells treated with BSA alone) and represent the mean ± SE of three independent experiments. .

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