Inhibition of cAMP/PKA Pathway Protects Optic Nerve Head Astrocytes against Oxidative Stress by Akt/Bax Phosphorylation-Mediated Mfn1/2 Oligomerization

Figure 4

Effects of elevated intracellular cAMP on mitochondrial bioenergetics and dynamics in ONH astrocytes. (a) Western blot analyses for the protein expression of Drp1, OPA1, and Mfn1 and Mfn2 in ONH astrocytes treated with dbcAMP (100 μM) for 1 h. Note that elevated intracellular cAMP induced increase of Drp1 protein expression in ONH astrocytes. (b, c) Cell viability/mitochondrial activity analysis using MTT assay in ONH astrocytes treated with dbcAMP or 8CPT-6phenyl-cAMP for 1 h. Note that cell viability was significantly decreased in ONH astrocytes by 8CPT-6phenyl-cAMP treatment in a dose-dependent manner, while dbcAMP treatment slightly increased cell viability. Data are shown as the (). , , and denote , , and (two-tailed unpaired Student’s -test), respectively. For each determination, the cAMP level and protein expression in controls were normalized to the protein contents and a value of 1.0, respectively. Data are shown as the (). , , and denote , , and , respectively.

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