RESUMO
Objective To investigate the interactions between histone deacetylas-1 (silent information regulator of transcription 1,SirT1) and signal transducer and activator of transcription 3 (STAT3) following exposure to oxidative stress of retinal pigmented epithelium (RPE) cells through gene knockout and overexpression techniques.Methods RPE cell line was cultured in vitro,followed by addition of H2O2 for inducing oxidative stress.The targeting knockout strategy (siRNA/shRNA) was used for silencing SirT1/STAT3 gene and lentiviral vectors (pRC/CMV STAT3 and PCRC/CMV) were transfected to RPE cells.RT-qPCR and Western blot were used to detect the expression of SirT1/STAT3 due to gene knockout and overexpression and deeply analyze the effects of SirT1/STAT3 on RPE cells exposed to oxidative stress.Results SirT1 activator (resveratrol) significantly reduced the expression of STAT3 mRNA to (3.0 ± 0.2) (P =0.048);and after SifT1 knockout,the expression of STAT3 mRNA in RPE cells was significantly increased to (6.9 ± 1.1) (P =0.025).During the oxidative stress of RPE cells after SifT1 knockout,the expression of STAT3 and phosphorylated STAT3 protein were significantly increased to 0.990 ±0.031 and 0.544 ±0.019,respectively (P =0.000,0.003).With the condition of oxidative stress,the over-expression of STAT3 reduced the SirT1 mRNA expression to 0.42 ± 0.16 (P =0.022),but SifT1 mRNA expression was significantly increased to 2.8 ±0.85 (P =0.015) during STAT3 knockdown.Conclusion SifT1 has a negative effect on the regulation of STAT3 expression during oxidative stress,which suggests that there is an equilibrium mechanism between SirT1 and STAT3 against oxidative stress.
