The Different Effects of Atorvastatin and Pravastatin on Cell Death and PARP Activity in Pancreatic NIT-1 Cells

Figure 3

AS- and PS-mediated cell deaths are through necrosis, not apoptosis and parthanatos. (a) NIT-1 cells in AS (20 μM) for 48 h exhibited decreased cell numbers. When pretreated with NSA or NEC-1, or DPQ, the cells exhibited an increased cell viability; the inhibitor zVAD did not change the percentage of NIT-1 cells. When pretreated with DPQ, the cells exhibited an increased cell viability in 20 μM PS treatment but remained unchanged after NSA, NEC-1, and zVAD pretreatment. (b) The RIP1-RIP3-MLKL interaction was enhanced following necrosis induction. Whole-cell extracts were used for anti-RIP3 immunoprecipitation. The immune complexes were analyzed using Western blot analysis with the indicated antibodies. Whole-cell lysates (30 μg, input) were analyzed by Western blotting for RIP3, RIP1, or MLKL. GAPDH is shown as the loading control. (c, d) Representative confocal images of AIF immunoreactivity (green) and nuclear DAPI staining (dark blue). AS and PS treatment did not induce AIF translocation to nucleus. Magnification: ×60. Scale bar: 20 μM. 300 μM H₂O₂ is included as positive control. (e) AIF is still normally localized to the mitochondrial (M) fraction in response to AS and PS treatment, not into nuclear (N) fraction. Proliferating cell nuclear antigen (PCNA) and cytochrome c oxidase subunit IV isoform 1 (COX4) were used as nuclear and mitochondrial marker proteins, respectively. , compared to the untreated group; , compared to the only AS- or PS-treated group; mean ± SD from three replicates.

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