Impact of epigallocatechin­3­gallate on expression of nuclear factor erythroid 2­related factor 2 and γ­glutamyl cysteine synthetase genes in oxidative stress­induced mouse renal tubular epithelial cells.

The aim of the present study was to investigate the antioxidant response mechanism of epigallocatechin­3­gallate (EGCG) in H2O2­induced mouse renal tubular epithelial cells (MRTECs). The cultured MRTECs were divided into normal, H2O2 (control) and EGCG treatment groups. The MTT assay was used to assess cell viability, and reverse transcription­quantitative polymerase chain reaction (RT­qPCR), immunocytochemical and western blot analyses were performed to detect the expression of nuclear factor erythroid 2­related factor 2 (Nrf2) and γ­glutamyl cysteine synthetase (γ­GCS). EGCG was able to mitigate H2O2­mediated cell damage. The RT­qPCR results demonstrated that EGCG was able to upregulate the gene expression of Nrf2 and γ­GCS in MRTECs in a dose­dependent manner. The immunocytochemistry and western blot analyses demonstrated that EGCG was able to increase the protein expression of Nrf2 and γ­GCS in MRTECs in a dose­dependent manner. Oxidative stress may lead to a decrease in the viability of MRTECs, while EGCG was able to promote the expression of Nrf2 and γ­GCS in MRTECs, thereby improving the antioxidant capacity of the cells and promoting the repair of oxidative stress injury.