Hcy dose-dependently increases Bach1 but not Nrf2 mRNA levels. Cells were treated with Hcy at indicated concentrations for 24 h. The mRNA levels of Bach1 and Nrf2 were quantified by qRT-PCR assay. Relative mRNA amounts of Bach1 and Nrf2 were normalized to GAPDH. Data shown are as means ± SEM of three independent experiments. *P < 0.05 vs. control.