A team of Israeli researchers has developed a new noninvasive method to assess iron levels in the brain using magnetic resonance imaging (MRI). The method could help diagnose and monitor neurodegenerative diseases such as Alzheimer’s and Parkinson’s.
Iron is an essential element for many biological processes, including oxygen transport, energy production, and DNA synthesis. However, too much iron can be toxic and cause oxidative stress, inflammation, and cell death. Iron accumulation in the brain has been linked to several neurological disorders, such as Alzheimer’s, Parkinson’s, multiple sclerosis, and stroke.
The brain regulates its iron levels through a complex system of proteins that control iron uptake, storage, and release. When this system is disrupted, iron can accumulate in certain brain regions and damage the neurons and glial cells that support them. This can lead to cognitive impairment, motor dysfunction, and behavioral changes.
Measuring iron levels in the brain
Currently, the only way to measure iron levels in the brain is by taking tissue samples from the brain or by performing an autopsy after death. These methods are invasive, risky, and impractical for clinical use. Therefore, there is a need for a noninvasive method that can measure iron levels in the brain in vivo.
MRI is a widely used imaging technique that can provide detailed information about the structure and function of the brain. MRI can also measure the magnetic properties of tissues, which are influenced by the presence of iron. However, conventional MRI methods are not sensitive enough to detect subtle changes in iron levels in different brain regions.
The new method developed by the Israeli researchers is based on a physical calculation that relates the magnetic properties of tissues to their iron content. The method uses two MRI parameters: R1 and R2, which reflect how fast the magnetic signals decay in tissues. By calculating the difference between R1 and R2 (R1-R2), the researchers were able to estimate the iron levels in different brain regions with high accuracy.
The researchers validated their method by comparing it with histological measurements of iron levels in post-mortem brain samples from patients with Alzheimer’s disease. They found a good correlation between the R1-R2 values and the iron content in various brain regions, such as the hippocampus, thalamus, putamen, and caudate nucleus.
Implications for diagnosis and treatment
The researchers applied their method to MRI scans of living patients with Alzheimer’s disease and healthy controls. They found that patients with Alzheimer’s disease had higher iron levels in the neocortex and deep gray matter than healthy controls. They also found that higher iron levels were associated with lower cognitive performance and more severe symptoms.
The researchers suggest that their method could be used as a biomarker for Alzheimer’s disease prediction and as a tool to monitor treatment response. For example, they propose that iron chelators, which are drugs that bind to excess iron and remove it from the body, could be tested as a potential treatment for Alzheimer’s disease. By measuring the changes in iron levels before and after treatment, the researchers could evaluate the efficacy and safety of these drugs.
The researchers also believe that their method could be applied to other neurodegenerative diseases that involve iron accumulation in the brain, such as Parkinson’s disease, multiple sclerosis, and stroke. By measuring iron levels in different brain regions, they could gain insights into the pathophysiology and progression of these diseases.
The researchers hope that their method will pave the way for new diagnostic and therapeutic approaches for neurodegenerative diseases. They also plan to further improve their method by incorporating other MRI parameters and developing more sophisticated algorithms.
