Nrf2-siRNA eliminated the protective effects of urate.

<p>(<b>a, b</b>) SH-SY5Y cells were transfected with scrambled siRNA (si-control) or two different siRNAs targeting human Nrf2 (si-Nrf2-1 and si-Nrf2-2). RNA interference efficiency was determined by immunoblotting at 24 h later. Mean ± SEM, n = 3. *<i>P</i><0.05, **<i>P</i><0.01 versus control group. (<b>c, d</b>) Cells were exposed to 6-OHDA (50 µmol/l) for 14 h, with or without urate pretreatment at 24 h after transfection. Cell viability (<b>c</b>) and intracellular glutathione level (<b>d</b>) were measured as described above. Results were presented as mean ± SEM, n = 3. *<i>P</i><0.05, **<i>P</i><0.01, ***<i>P</i><0.001.