FIGURE 7:

PKCδ and Drp1 complex is associated with increased mitochondrial fragmentation and neuronal cell death. (A) SH-SY5Y neuronal cells were treated with δV1-1 (1 μM) or control peptide TAT (1 μM) 15 min before addition of Ang II (1 μM for 6 h; middle panel) or H₂O₂ (200 μM for 6 h; right panel). The cells were then stained with MitoTracker Green (100 nM) for 30 min and Hoechst stain (scale bar 0.5 μm). Note that control peptide TAT has no effect on mitochondrial morphology under normal conditions (unpublished data). (B) Histogram: The percentage of cells with fragmented mitochondria relative to the total number of cells is presented as the mean ± SE of three independent experiments. At least 200 cells per group were counted. **p < 0.01. (C) SH-SY5Y cells were transfected with control siRNA and Drp1 siRNA. After 48 h, the cells were incubated with Ang II for 6 h and then stained with MitoTracker Green (100 nM; 30 min) and with Hoechst stain (scale bar 0.5 μm). Cell viability was measure by MTT assay. (D) SH-SY5Y cells were treated with TAT or δV1-1 15 min before treatment with Ang II (2 d) or H₂O₂ (1 d). *p < 0.05 vs. control; ^#p < 0.05 vs. TAT-treated cells. The data are presented as the mean ± SE of three independent experiments. (E) SH-SY5Y cells were treated with Ang II for 2 d following treatment with Drp1 siRNA or with control siRNA. *^#p < 0.05. The data are presented as mean ± SE (three independent experiments).