Increased levels of 4-HNE protein adducts in the frontal cortex of 4-month-old 5XFAD mice. Representative immunoblots of the frontal cortex (A), hippocampus (C), and striatum (E) of 4-month-old 5XFAD and non-Tg control mice. Five bands with evident immunoreactivity (40, 55, 70, 120, and 170 kDa) were selected and normalized according to 55 kDa band of Ponceau S staining. 4-HNE levels in the frontal cortex (B), hippocampus (D), and striatum (F) of 5XFAD mice represented as a percentage of the levels in non-Tg control mice. (B) 4-HNE levels in the frontal cortex of 5XFAD mice were significantly higher than those in non-Tg mice in specific band sizes (120 and 170 kDa). In the hippocampus (D) and striatum (F), no significant differences between the two mice were observed in any band size. Non-Tg, n = 6–8; 5XFAD, n = 6–8; * p < 0.05.