A simulation of the brain nerve electric signal. Credit: MediaProduction/ iStock / Getty Images Plus
An MRI-based study reveals that depleted levels of the antioxidant glutathione with concomitant rise of iron in a specific brain region convert mild cognitive impairment (MCI) to Alzheimer’s disease1.
Normally, glutathione binds to free iron and prevents its abnormal build-up in the brain. The abnormal change affects the left hippocampus, a brain region that is responsible for forming verbal memory.
These findings will open up new avenues for effective clinical trials to arrest MCI by increasing glutathione levels in the brain, says a team at the National Brain Research Centre in Haryana.
Neuroscientists, led by Pravat Mandal, carried out quantitative susceptibility mapping, an advanced MRI technique to evaluate the distribution of iron and other biomarkers in the brain of 72 people. They included healthy individuals and MCI and Alzheimer’s patients, with a mean age of 69.
The researchers found that brain glutathione levels dropped significantly in the patients with MCI and Alzheimer’s compared with those of the healthy participants. A higher level of iron was observed in the left hippocampus of the Alzheimer’s patients.
Monitoring glutathione and iron levels in the left hippocampus provided a diagnostic accuracy of 82.1%, with 81.8% sensitivity and 82.4% specificity for distinguishing the Alzheimer’s patients from people without Alzheimer’s.
The researchers say that an abnormal iron build-up in the left hippocampus generates free radicals and reactive oxygen species, which cause oxidative stress, triggering a regulated cell death.
