Peroxiredoxins (Prxs) are antioxidant enzymes that contain one or two cysteine (Cys) residues in their active site . There are six isoforms divided into three groups: the 2-Cys Prxs (Prx 1, 2, 3, and 4), the atypical 2-Cys Prx (Prx 5), and the 1-Cys Prx (Prx 6) . In neurons, intracellular Prxs, which are induced by various oxidative stimuli, protect against oxidative radical damage by ROS . Type II Prx 1, also known as Prx 2, is predominantly expressed in the brain . The protein level of Prx 2 is increased in aging and AD brains, suggesting that Prx 2 is involved in the elevated neuronal antioxidant response under oxidative stress . The proteomic analysis of the hippocampus in AD patients shows that the expression of Prx 2 increases compared with age-matched controls . Prx 2-deficient mice show remarkably increased susceptibility to oxidative stress-induced tissue damage . Therefore, the increased expression of Prx 2 might decrease oxidative damage, improving abnormalities of neurons and glia in the brain and subsequent dementia.