Activation of Transcription Factor Nrf2 in HeLa Cells under the Action of Nitrosyl Iron Complex with N-Ethylthiourea.

We studied the effect of an NO donor, nitrosyl iron complex with N-ethylthiourea, on Nrf2-dependent antioxidant system activation of tumor cells in vitro. The complex increased intracellular accumulation of Nrf2 transcription factor and induced its nuclear translocation. It was shown that both heme oxygenase-1 gene and protein expression increased significantly under the influence of the complex. Nrf2 activation was accompanied by a decrease in the intracellular accumulation of proinflammatory transcription factor NF-κB p65 subunit and expression of its target genes. The cytotoxic effect of N-ethylthiourea leads to induction of Nrf2/HO-1 antioxidant response and suppression of NF-κB-dependent processes in tumor cells.