Figure 3.

Cyclo(His-Pro) triggers nuclear translocation of Nrf2 leading to changes in the antioxidant gene expression pattern in PC12 cells. Cells were incubated with 50 μM cyclo(His-Pro) for 24 hrs prior to treatment with 100 μM H₂O₂. (A) Nrf2 protein in cytosol (white bars) and nuclear (grey bars) fractions. The nuclear and cytosolic extracts containing 40 |ag of proteins were subjected to Western blotting analysis with the indicated antibodies. Anti-α-tubulin and anti-lamin B antibodies were used as markers for the cytosolic and nuclear extracts, respectively. Quantification of the scanned band intensities revealed a ∼2-fold increase in Nrf2 intensity in the nuclear fraction (lower panel). (B) Real-time PCR analyses of the samples revealing changes in the expression of several genes, whose values were normalized to β-actin expression, and presented as 2^−ΔΔ. Relative mRNA abundance of each gene in untreated cells was assumed to be 1.0 (control). Results are given as mean ± S.D. values for n= 3 independent experiments. *P< 0.05 versus control; #P< 0.05 versus H₂O₂-treated cells.