Figure 2. Increased oxidative stress and decreased antioxidant defense were present in the hypertrophic ligamentum flavum. The ROS levels, inclusive of (A) Superoxide anion and (B) Hydrogen peroxide, were higher in the LSS group compared to the LDH group. The expressions of (C) Malondialdehyde (MDA) and (D) Nitrotyrosine, which are markers of damage from oxidative stress, were higher in the LSS group. Meanwhile, the expressions of (E) Glutathione peroxidase (GPX1), (F) Glutathione (GSH), and (G) Superoxide dismutase (SOD) activity were decreased in the LSS group. (n = 21 and 43, respectively; * p < 0.05, *** p < 0.001 compared to the LDH group; the value was generated by unpaired t-test.) (The lanes on Figure 2E were run on the same gel but were noncontiguous.).