The correlation of asymmetrical dimethylarginine level and oxidative stress to the onset of Alzheimer’s disease

This study is to investigate the influence and mechanism of action of asymmetrical dimethyl-   arginine (ADMA) and the induced oxidative stress level on Alzheimer’s disease (AD) incidence.  ADMA   concentration, nitric oxide, Aβ₄₀/Aβ₄₂ ratio, inducible NO synthase (iNOS) activity and the concentrations of the induced free radicals including malondialdehyde (MDA), 3-nitrotyrosine (3-NT) and peroxynitrite (ONOO⁻) in the cerebrospinal fluid (CSF) from 34 neurologically normal controls and 37 AD patients were quantitatively  determined and statistically compared.  The results showed that the ADMA concentration significantly      decreased in AD patients, and it showed negative correlation with the NO, iNOS activity, and showed positive correlation with MMSE score.  ADMA concentration was negatively correlated with Aβ₄₀/Aβ₄₂ ratio (P < 0.01) with the observation that Aβ₄₀/Aβ₄₂ ratio increased while ADMA level decreased in CSF in AD patients.  The concentration levels of MDA, 3-NT and ROS significantly increased compared with the control with all the    P values less than 0.05.  These findings suggested that the ADMA disorder and the oxidative damage effect of the induced free radicals in CSF of AD patients are an important mechanism of AD incidence, and their joint regulation may provide new idea for the prevention and clinical treatment of AD.