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

Figure 3

Effects of oxidative stress on mitochondrial bioenergetics and dynamics in ONH astrocytes. (a) OCR changes in ONH astrocytes treated with H₂O₂ (50 μM) for 1 h. Oligomycin A and FCCP were sequentially added at the indicated time point. Basal respiration indicates the starting basal OCR and the value which was set to 100%. Maximum respiration represents the ratio between FCCP uncoupled OCR and basal OCR. (b) Western blot analyses for the protein expression of Drp1, OPA1, and Mfn1 and Mfn2 in ONH astrocytes treated with H₂O₂ (50 μM) for 1 h. Note that oxidative stress induced loss of Drp1 protein expression in ONH astrocytes. (c) Real-time RT-PCR analysis for the mRNA expression of Drp1, OPA1, and Mfn1 and Mfn2 genes in ONH astrocytes treated with H₂O₂ (50 μM) for 1 h. Note that oxidative stress did not change gene expression. For each determination, the expression levels of mRNAs and proteins in controls were normalized to a value of 100% and 1.0, respectively. Data are shown as the (). and denote and , respectively.

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