Oxidative imbalance in patients with mild cognitive impairment and Alzheimer's disease

• Published in: Neurobiology of aging Vol. 27; no. 2; pp. 262 - 269
• Main Authors: Guidi, Ilaria, Galimberti, Daniela, Lonati, Silvia, Novembrino, Cristina, Bamonti, Fabrizia, Tiriticco, Marco, Fenoglio, Chiara, Venturelli, Eliana, Baron, Pierluigi, Bresolin, Nereo, Scarpini, Elio
• Format: Journal Article
• Language: English
• Published: London Elsevier Inc 01-02-2006; Elsevier Science
• Subjects: Aged; Aged, 80 and over; Alzheimer Disease - complications; Alzheimer Disease - genetics; Alzheimer Disease - metabolism; Alzheimer's disease; Apolipoprotein E4; Apolipoproteins E - genetics; Biological and medical sciences; Case-Control Studies; Cocaine - blood; Cognition Disorders - complications; Cognition Disorders - genetics; Cognition Disorders - metabolism; Confidence Intervals; Degenerative and inherited degenerative diseases of the nervous system. Leukodystrophies. Prion diseases; Epinephrine - blood; Female; Homocystine - blood; Humans; Male; Medical sciences; Mental Status Schedule; Middle Aged; Mild cognitive impairment; Neurology; Odds Ratio; Reactive oxygen species; Reactive Oxygen Species - metabolism; Retrospective Studies; Sex Factors; Tetracaine - blood; Total antioxidant capacity; Total plasma homocysteine; Reactive oxygen species; Total antioxidant capacity; Total plasma homocysteine; Mild cognitive impairment; Alzheimer's disease; Human; Mild cognitive impairment: Alzheimer's disease; Nervous system diseases; Alzheimer disease; Antioxidant; Cerebral disorder; Homocystein; Central nervous system disease; Degenerative disease; mild cognitive impairment
• ISSN: 0197-4580; 1558-1497
• DOI: 10.1016/j.neurobiolaging.2005.01.001

Increasing evidence supports a role of oxidative imbalance, characterized by impaired antioxidant enzymatic activity and increased reactive oxygen species (ROS) production, in mild cognitive impairment (MCI) and Alzheimer's disease (AD) pathogenesis. Hyperhomocysteinemia, another risk factor for AD, also contributes to oxidative damage. Plasma total homocysteine (tHcy) and ROS levels, and total antioxidant capacity (TAC) were determined in 71 AD, 36 MCI and 28 vascular dementia (VaD) patients as well as in 44 age-matched controls. tHcy levels were significantly increased in patients with AD and VaD an a trend towards an increase in multiple domain MCI was observed. TAC was significantly decreased in AD as well as MCI, but not in VaD patients. In AD patients, a negative correlation was found between TAC and disease duration. ROS levels did not differ among groups, but were correlated with age.
In conclusion, a pattern characterized by increased tHcy levels and decreased TAC is present in AD as well as MCI patients. While increased tHcy levels were also found in VaD, TAC modifications occur specifically in AD. ROS levels appear to be correlated with age rather than with a specific dementing disorder, thus leading to the hypothesis that oxidative imbalance observed in AD could be due to a decreased TAC.