Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 46 1 2008 02 15 11 16 A. Vaisi-Raygani Z. Rahimi M. Zahraie M. Noroozian A. Pourmotabbed 2015 09 28 The etiopathogenesis of dementia in Alzheimer's disease (AD) is still unclear. However, long-term oxidative stress is believed to be one of the major contributing factors in progression of neuronal degeneration and decline of cognitive function in AD. In order to assess the presence of oxidative stress in AD, we examined the enzymatic activities of the erythrocyte Cu-Zn superoxide dismutase (Cu-Zn SOD), glutathione peroxidase (GSH-Px), catalase (CAT), and plasma level of total antioxidant status (TAS) in AD and control groups (age and sex-matched). The results showed that the Cu-Zn SOD activity was significantly higher and the level of GSH-Px and TAS activities were significantly lower in AD subjects than that in the control group (2111±324 U/grHb, 43.7±11.6 U/grHb, and 1.17 ±0.23 mmol/L compared with 1371±211 U/gHb; t= -2.17, p=0.036, 56.3±9.5 U/gHb; t=3.8, p=0.014, and 1.54±0.2 mmol/L; t=11.18, P https://acta.tums.ac.ir/index.php/acta/article/view/3434 https://acta.tums.ac.ir/index.php/acta/article/download/3434/3411