Andrographolide Induces Apoptosis of C6 Glioma Cells via the ERK-p53-Caspase 7-PARP Pathway

Figure 2

The apoptotic effects of AND on C6 glioma cells, and the involved signaling molecules. (a) 4,6-Diamidino-2-phenylindole dilactate (DAPI) staining. The cells were treated with 0.1% DMSO (CTL), 15 μM AND, 15 μM AND plus 50 μM DEVD, and 15 μM AND plus 5 µg/mL 3AB for 12 h and stained with DAPI. Apoptotic nuclei (arrowheads) were identified by nuclear morphology. Bar = 20 μm. (b) Quantitative data from (a). 𝑁=7. ^∗𝑃<0.05, ^∗∗𝑃<0.01, compared to the control group. ^##𝑃<0.01, as compared to the AND group. ((c)–(e)) The protein expression levels of cleaved caspase (c-caspase) 3 (c), c-caspase 7 (d), and cleaved PARP (c-PARP) (e). Cells were treated with 15 μM AND for 0, 6, 12, or 24 h, and cell lysates were analyzed for target proteins and GADPH (internal standard). 𝑁=3. (f) Effects of DEVD. The cells were treated with 0.1% DMSO, 15 μM AND, 15 μM AND plus 50 μM DEVD, or 50 μM DEVD for 24 h, and cell lysates were analyzed for cleaved PARP and GADPH. 𝑁=3. ^∗𝑃<0.05, ^∗∗𝑃<0.01, as compared to the control group. ^##𝑃<0.01 as compared to the AND group.

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