Figure 2.

Lentiviral overexpression of PRX2 enhances PRX activity and PRX oxidation in DA neurons. A, B, 6-OHDA induces PRX oxidation in MN9D cells. Neuronal-differentiated MN9D cells were treated with 6-OHDA (50 μm). At the indicated time points, cell extracts were subjected to immunoblotting against PRX-SO₃ or PRX2 immunoprecipitation followed by immunoblotting against PRX-SO₃. The graph (B) summarizes the temporal profiles of increases in total PRX-SO₃ and PRX2 IP-specific PRX-SO₃ (PRX2-SO₃). *p < 0.05; **p < 0.01 versus vehicle controls; n = 4/condition. C, MN9D cells were infected with Lenti-PRX2, the empty vector (Lenti) or Lenti-GFP (data not shown) for 3 d, and then challenged with 6-OHDA. Cellular PRX activity was measured at the indicated time points, and data were expressed as percentage changes over vehicle controls. *p < 0.05, **p < 0.01 versus vehicle controls; ##p < 0.01 versus Lenti vector-infected cells; n = 3/condition. D–G, 6-OHDA lesioning induces PRX oxidation and reduced PRX activity in mouse SNc. Mice were subjected to striatal infusion of 6-OHDA (3.0 μg), and at the indicated time points the SNc extracts were processed for immunoblotting against PRX2 (D, E), PRX-SO₃ (D, F), and the PRX activity assay (G). *p < 0.05, **p < 0.01 versus saline-injection controls; n = 5–6/group. H–K, Lenti-PRX2 gene delivery increases PRX activity and PRX oxidation in mouse SNc. Mouse SNc was infected for 21 d with empty lentiviral vector (Lenti) or Lenti-PRX2 (HA-tagged), and then received striatal infusion of 6-OHDA (3.0 μg) or saline of the same volume. SNc extracts were processed for immunoblotting against PRX2 (H, I), HA (H), PRX-SO₃ (H, J), and the PRX activity assay (K). *p < 0.05, **p < 0.01 versus saline controls; #p < 0.05; ##p < 0.01 versus empty lentivirus group; n = 5–6/group. L, Double-label immunofluoroscent staining for HA (HA-tagged PRX2, green) and TH (red) in the SNc at 21 d after brain inoculation with either empty lentiviral vector (a, b, low magnification; c, d, high magnification) or Lenti-PRX2 (e, f, low magnification; g, h, high magnification). Scale bars: a, b, e, f, 100 μm; c, d, g, h, 30 μm.