Activation of JNK and p38 involves in the ALA-PDT mediated cell death but not relates to the AMPK activation and autophagic cell death. (A) PC12 and CL1-0 cells were treated with 1 mM ALA for 3 hr, and then irradiated under the light dose of 2 and 12 J/cm2, respectively. The cell lysates were collected at the time indicated after ALA-PDT. Kinase activity and protein level of the three MAPKs were analyzed by western blot analysis with specific anti-phospho- or anti-MAPK antibodies. β-actin was also used as an internal control. Representative results from at least three independent experiments are shown. (B) PC12 cells were subjected ALA-PDT with or without the inhibitors of the three MAPKs. The blockers applied were PD98059 (ERK inhibitor, 40 μM), SP600125 (JNK inhibitor, 40 μM), and SB203580 (p38 inhibitor, 40 μM). Cell survival was analyzed 24 hr post ALA-PDT. Significantly different from cells treated with ALA-PDT only; **P < 0.01. (C) PC12 cells were subjected ALA-PDT in the presence of the three MAPKs inhibitors. Cell lysates were collected 30 minutes post ALA-PDT (1 mM ALA, 2 J/cm2). AMPK activity was analyzed by western blot analysis using antibody recognized the p-AMPK. (D) In the presence of the inhibitor of JNK or p38, PC12 and CL1-0 cells were treated with 1 mM ALA for 3 hr, and then irradiated under the light dose of 2 and 12 J/cm2, respectively. Cell lysates were collected at 8 hr post ALA-PDT and further used for LC-3 immunoblot analysis.