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

Figure 5

The expression of MAPK and the effect of MAPK inhibitors on AND-induced apoptosis in C6 glioma cells. (a) Time course study on MAPK activation. Cells were treated with 15 μM AND for 0, 6, 12, or 24 h, and cell lysates were analyzed for p-JNK, pERK, p-38, or GADPH. The lower panel is the quantization of p-JNK, p-ERK, and p-p38 levels ^∗𝑃<0.05, ^∗∗𝑃<0.01, compared with the 0 h control. (b) The effect of ERK inhibitor on p53 phosphorylation. Cells were treated with 0.01% DMSO (CTL) or 15 μM AND with or without 30 μM PD98059 and were blotted for p-p53. 𝑁=4. ^∗∗𝑃<0.01, as compared to the CTL group. ^##𝑃<0.01, compared to the AND group. (c) The effect of ERK inhibitor on AND-induced cell death. Cells were treated with 0.01% DMSO (CTL) or 15 μM AND with or without 30 μM PD98059 and then were stained with DAPI. (d) Quantization of the apoptotic cell percentage. 𝑁=4. ^∗∗𝑃<0.01, compared to the DMSO group. ^##𝑃<0.01, as compared to the AND group.

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