Figure 7.

Influence of inflammatory cytokines and streptozotocin (STZ) on apoptosis of INS-1 cell lines. In panel (a), control INS-1 cells or iPLA₂ γ-knockdown INS-1 cells (iPLA₂-KD) were incubated with vehicle only (light bars) or with IL-1β (5 ng/mL) and IFN-γ (80 ng/mL) (dark bars) for 16 hr, and the percentages of apoptotic cells were then determined by FACS as described in Experimental Procedures. In panel (b), control INS-1 cells (light bars) or iPLA₂ γ-Knockdown INS-1 cells (dark bars) were incubated with vehicle alone or with varied concentrations of STZ (5 mM or 7.5 mM) for 16 hr, and the percentages of apoptotic cells were then determined as in panel (a). Mean values ± SEM (n = 4) are displayed. An asterisk (*) indicates a significant difference (P < 0.05) between control cells and iPLA₂ γ-KD cells. An (X) indicates a significant difference (P < 0.05) from the vehicle-treated condition.