Figure 6.

Involvement of ASK1, MKK3, MKK6, and p38MAPK in Aβ-induced p53 phosphorylation in CECs. A, CECs were transiently transfected with pcDNA or ASK1 DN for 24 h. After transfection, cells were treated with vehicle or 20 μm Aβ for 1 h and then harvested for immunoblotting to assess the level of p53 phosphorylation at Ser15 using an anti-pSer15–p53 anti-body. Equal loading in each lane is reflected by approximately similar intensities of the α-tubulin bands. Compiled results are shown at the bottom. *p < 0.05 compared with the pcDNA (mock transfection) group in the presence of Aβ. B, CECs were transiently transfected with pcDNA, MKK3 DN, or MKK6 DN for 24 h. After transfection, cells were treated with vehicle or 20 μm Aβ for 1 h and then harvested, and the level of p53 phosphorylation at Ser15 was determined as described in A. Equal loading in each lane is reflected by approximately similar intensities of the α-tubulin bands. Compiled results are shown at the bottom. *p < 0.05 compared with the pcDNA (mock transfection) group in the presence of Aβ. C, CECs were treated with 10 μm SB203580 (SB), specific p38MAPK inhibitor, for 30 min, followed by vehicle or 20 μm Aβ for another 1 h and were then harvested for assessing the level of p53 phosphorylation at Ser15 as described in A. Equal loading in each lane is reflected by approximately similar intensities of the α-tubulin bands. Compiled results are shown at the bottom. *p < 0.05 compared with the pcDNA (mock transfection) group in the presence of Aβ.