Fig. 6: Inhibition of PGC1A in RPE cells reduced mitochondrial mass and activity, mitochondrial membrane potential, antioxidant enzymes, and increased susceptibility to oxidative stress.

A mRNA levels of mitochondrial biosynthesis-related transcription factors ERRα, ERRβ, ERRγ, NRF1, and TFAM; mitochondrial dynamics genes, DRP1 and OPA1; mitochondrial respiratory chain complex1 core subunit genes, NDUFS2 and NDUFS8; oxidative stress-regulating gene, NFE2L2; and antioxidant enzyme genes SOD1, SOD2, and CAT (n = 3). B Immunostaining of mitochondria (green) by MitoView, showing reduced mitochondrial mass in ARPE19-PGC1A KO compared to Scramble control cells. Hoechst 33342 (blue) was used to stain nuclei. The scale bar represents 100μm. C, D Protein levels of NFE2L2, SOD2, and Catalase were significantly decreased in ARPE19-PGC1A KO cells (n = 3). E Mitochondrial membrane potential quantification in ARPE19-PGC1A KO and Scramble control groups (n = 3). F mtDNA copy number was significantly reduced in ARPE19-PGC1A KO as compared to Scramble control cells (n = 3). G Cell viability was significantly lower in ARPE19-PGC1A KO cells as compared to the control group under increasing concentration of H₂O₂ treatment for 24 h (n = 3). GAPDH was used for internal control and statistical normalization (n = 3). ImageJ was used for densitometry analysis. Unpaired t-test was performed for statistical analysis. Graph represents Mean ± SEM, *P ≤ 0.05, **P ≤ 0.01, ***P ≤ 0.001, ****P ≤ 0.0001.