Fig. 3. Activation of cAMP/PKA pathway induces ONH astrocytes death via Bax and caspase-3 activation.
a Real-time RT-PCR analysis of NFκB- and FoxO-dependent gene expression in ONH astrocytes treated with forskolin (10 μM) for 1 h. Data were normalized by GAPDH expression. b Real-time RT-PCR analysis of Bim mRNA expression in ONH astrocytes treated with forskolin (10 μM) or forskolin (10 μM) plus H89 (10 μM) for 1 h. Note that PKA dependent-regulation of Bim mRNA expression. c and d Cell viability and cell death analysis using MTT assay (c) and LDH assay (d) in ONH astrocytes co-treated with forskolin (10 μM) and IGF-1 (100 nM) for 24 h. e Co-IP analysis of Bim and Bcl-xL interaction in ONH astrocytes treated with forskolin (10 μM), H89 (10 μM) or forskolin (10 μM) plus H89 (10 μM) for 1 h. f Immunoblot analysis of Bim and activated Bax in ONH astrocytes co-treated with forskolin (10 μM) and rolipram (2 μM) for 24 h. g Immunoblot analyses of pAKT, AKT, activated Bax and caspase-3 in ONH astrocyte treated with forskolin (10 μM), Rp-cAMP (50 μM), or H89 (10 μM) for 24 h. For each determination, the mRNA, ratio of pAKT/AKT protein and other protein expression in controls was normalized to a value of 100% or 1.0. Data are shown as the mean ± S.D. (n = 3). *P < 0.05; **P < 0.01; ***P < 0.001 (two-tailed unpaired Student’s t-test)