Hippocampal glutathione depletion with enhanced iron level in patients with mild cognitive impairment and Alzheimer's disease compared with healthy elderly participants

Oxidative stress has been implicated in Alzheimer's disease, and it is potentially driven by the depletion of primary antioxidant, glutathione, as well as elevation of the pro-oxidant, iron. Present study evaluates glutathione level by magnetic resonance spectroscopy, iron deposition by quantitative susceptibility mapping in left hippocampus, as well as the neuropsychological scores of healthy old participants (N = 25), mild cognitive impairment (N = 16) and Alzheimer's disease patients (N = 31). Glutathione was found to be significantly depleted in mild cognitive impaired (P < 0.05) and Alzheimer's disease patients (P < 0.001) as compared with healthy old participants. A significant higher level of iron was observed in left hippocampus region for Alzheimer's disease patients as compared with healthy old (P < 0.05) and mild cognitive impairment (P < 0.05). Multivariate receiver-operating curve analysis for combined glutathione and iron in left hippocampus region provided diagnostic accuracy of 82.1%, with 81.8% sensitivity and 82.4% specificity for diagnosing Alzheimer's disease patients from healthy old participants. We conclude that tandem glutathione and iron provides novel avenue to investigate further research in Alzheimer's disease. Mandal et al. measured left hippocampal glutathione using magnetic resonance spectroscopy together with iron deposition measured using quantitative susceptibility mapping of the same region. Significant differences in glutathione and iron levels were found in Alzheimer's disease as compared with healthy old participants. Pro-oxidant iron has been examined with glutathione in the same group of population for the first time.