Figure 2

Figure 2

Protective effect of verapamil in MIN6 cells exposed to STZ, T1D-cytomix, or T2D-cytomix stressors. Bar graphs presenting MTT assay results as a ratio of each treatment over viability of MIN6 cells maintained in 5.6 mM glucose. (A–C) Cells were stressed with streptozotocin (STZ). (A) Cells were pretreated with different concentrations (1, 5, 10, and 50 μM) of verapamil for 24 h, the media were changed, and cells were stressed by 3 mM of STZ for another 24 h. (B) Cells were treated with a combination of STZ (3 mM) and verapamil (1, 5, 10, and 50 μM) for 24 h. (C) Cells were pretreated with verapamil (1, 5, 10, and 50 μM) for 24 h, then fresh media containing both STZ (3 mM) and verapamil (1, 5, 10, and 50 μM) were supplied to the cells for another 24 h. (D–F) Cells were stressed with T1D-cytomix (IL-1β: 50 ng/mL, TNF-α: 50 ng/mL, and INF-γ: 100 ng/mL) in each setting independently. (D) Cells were pretreated with different concentrations (1, 5, 10, and 50 μM) of verapamil for 24 h, then media were changed, and cells were stressed with T1D-cytomix for another 24 h. (E) Cells were treated with a combination of T1D-cytomix and verapamil (1, 5, 10, and 50 μM) for 24 h. (F) Cells were pretreated with verapamil (1, 5, 10, and 50 μM) for 24 h, then fresh media containing both T1D-cytomix and verapamil (1, 5, 10, and 50 μM) were supplied to the cells for another 24 h. (G–I) Bar graphs presenting MTT assay results as a ratio of each treatment over the viability of cells stressed by T2D-cytomix (IL-1β: 50 ng/mL, TNF-α: 50 ng/mL, and Palmitic Acid: 500 μM) in each setting independently. (G) Cells were pretreated with different concentrations (1, 5, 10, and 50 μM) of verapamil for 24 h, then media were changed, and cells were stressed with T2D-cytomix for another 24 h. (H) Cells were treated with a combination of T2D-cytomix and different concentrations (1, 5, 10, and 50 μM) of verapamil for 24 h. (I) Cells were pretreated with different concentrations (1, 5, 10, and 50 μM) of verapamil for 24 h, then fresh media containing both T2D-cytomix and different concentrations (1, 5, 10, and 50 μM) of verapamil were supplied to the cells for another 24 h. Each experiment was performed by at least five independent repeats. The difference between the groups was statistically analyzed using two-way analysis of variance (ANOVA), and p values < 0.05 were considered significant difference. Data are presented as mean ± SEM, * p-value < 0.05, ** p-value < 0.01, *** p-value < 0.001, and **** p-value < 0.0001. ns: non-significant.