Vitamin C Protected Human Retinal Pigmented Epithelium from Oxidant Injury Depending on Regulating SIRT1

Figure 4

Regulation of FoxO3 and p53 was involved in the expression of SIRT1 rather than Vit C. ARPE-19 cells underwent SIRT1 knockdown and overexpression of SIRT1 by using siRNA (SIRT1si group), pRC/CMV-SRIT1 (SIRT1up group), and its control (C-SIRT1si and C-SIRT1up groups, resp.). Then, cells were exposed to 100 μM of H₂O₂ for 12 h after being incubated for 24 h with 100 μM of Vit C. The expression of p53 (a) and FOXO3 (b) mRNA was detected by qRT-PCR and was normalized by 2^−ΔΔCt method as relative quantification. The expression of SIRT1, p53, and FOXO3 proteins was assayed by western blot in ARPE-19 cells with indicated treatments (c). Bars represented mean ± SD of three independent experiments. ANOVA was performed to analyze the differences statistically. Statisticalsignificance was expressed as ^∗𝑃<0.05 and ^∗∗𝑃<0.01.

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(b)

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