Figure 1

Tranilast protects INS-1 cells from PA-induced cell death. (A) Schematic representation of tranilast selection from high throughput screening of Korea Chemical Bank. (B) Inhibitory effects of tranilast on FoxO-1, 3a, and 4 were determined using HepG2 cells after transfection with FoxO-1 vector, and IRE vector as described in Methods. (C) Effect of tranilast on cell viability was measured using MTT assay following incubation of INS-1 cells with PA (500 μM) for 24 h in the presence or absence of tranilast at the indicated concentrations. (D) INS-1 cells were treated with PA (500 μM) for 24 h in the presence or absence of various concentrations of tranilast. Induction of apoptosis was measured using a cell death detection ELISA kit. (E) Caspase-3 and -9 activities were measured using the chromogenic substrates Ac-DEVD-pNA and Ac-LEHD-pNA, respectively. (F) DAPI staining of INS-1 cells following incubation with PA and tranilast. Representative results are shown (scale bar = 20 μm). Data are expressed as mean ± standard deviation (SD) of three independent experiments, each done in duplicate. ##p < 0.01, ###p < 0.005 versus control, *p < 0.05, **p < 0.01, ***p < 0.005 versus PA alone.