People with Parkinson's show altered iron levels in their brains

November 28, 2016
DZNE researchers have found altered iron levels in the brains of people with Parkinson’s. With excess iron in some areas and decreased iron content in others. For example, iron concentration in the “substantia nigra” – a brain area involved in movement control – was unusually high. This is exemplified by these two brain scans: They show the substantia nigra in a healthy control and a patient. High QSM signal (red and yellow) indicates high iron content. Image: DZNE/Julio Acosta-Cabronero

Iron occurs naturally in the human body. However, in people with Parkinson's disease it distributes in an unusual way over the brain. This is the result of a study by the DZNE that has been published in the journal Brain. Researchers headed by Professor Peter Nestor applied a special type of magnetic resonance imaging (MRI) allowing them to map iron levels in the entire brain—it is the first time this is done in Parkinson's disease.

This approach could improve the diagnosis of Parkinson's and shine new light on the involved .

Parkinson's is a neurodegenerative disease characterized by movement disorders and potentially dementia at a later stage. Pathological hallmarks include damage to neurons and the presence of a protein called "alpha-synuclein". However, the underlying disease mechanisms are far from being fully understood. "As yet we don't know the causes for Parkinson's. However, -mediated oxidative stress has been proposed as a potential pathomechanism," says Julio Acosta-Cabronero, a postdoc researcher at Nestor's lab at the DZNE's Magdeburg site and leading author of the present publication. "For this reason, we looked for ways of mapping in the whole brain. This has not been done before in Parkinson's. To date, iron analysis was limited to specific regions."

Iron is indispensable for the human metabolism. It manifests e. g. in red blood cells, enzymes and particular proteins that serve as an iron deposit. However, iron is also potentially harmful as it is able to trigger production of reactive molecular species that may cause "oxidative stress" and ultimately damage to neurons.

Mapping magnetic properties

For the current study, the DZNE researchers teamed up with colleagues from the University Magdeburg's neurology department. Together, they examined the brains of 25 persons with Parkinson's and 50 healthy subjects by using a special MRI technique called QSM, which is the acronym for "quantitative susceptibility mapping".

QSM is a quite recent development. As with conventional MRI, it is non-invasive and relies on a combination of magnetic fields, electromagnetic waves and analysis software to generate pictures of the insides of the . However, QSM benefits from raw data usually discarded in conventional MRI. As a consequence, QSM can probe a magnetic parameter indicating metallic presence. "QSM shows how magnetic susceptibility varies across the brain. In our study, this is mainly caused by local variations in iron concentration. The bottom line is that we are mapping the spatial distribution of iron in the brain," Acosta-Cabronero explains.

"MRI in neurodegenerative diseases has mostly focused on measuring the degeneration itself, meanwhile we know extremely little about its causes. We hope that by probing with new approaches such as whole-brain QSM, we may be able to get clues to the mechanisms of disease," Peter Nestor says.

By matching the brain scans of patients and healthy controls, the researchers were able to identify pathological changes. "In Parkinson's patients we found excess iron, as expected from previous studies, in the substantia nigra but also in extensive areas of the neocortex," Nestor says.

In contrast, standard MRI showed no significant differences between people affected by Parkinson's and healthy study participants. In addition, QSM revealed anomalies also in areas that until now have attracted little interest in Parkinson's. "There is a region in the lower brain called dentate nucleus, which is normally iron rich. Yet, our whole-brain approach indicated decreased iron content in this area in Parkinson's patients - extremely so in some individuals - highlighting how this method can open new avenues of investigation in Parkinson's disease," Nestor says.

Potential biomarkers

This approach, the neuroscientist believes, might also be suitable for clinical routine: "QSM relies on measurement data that standard MRI does not make use of. However, most clinical scanners would in principle be able to acquire and save this information for further processing. Therefore, whole-brain maps that reflect the landscape of magnetic susceptibility could potentially serve as biomarkers for disease. In other words: QSM might help to improve the diagnosis of Parkinson's and related disorders."

Explore further: Accelerated MRI brain mapping technique to improve neurodegenerative diagnosis

More information: Julio Acosta-Cabronero et al, The whole-brain pattern of magnetic susceptibility perturbations in Parkinson's disease, Brain (2016). DOI: 10.1093/brain/aww278

Related Stories

Accelerated MRI brain mapping technique to improve neurodegenerative diagnosis

November 16, 2016
A new brain imaging technique developed by University of Queensland researchers is paving the way for improved diagnosis and treatment of neurodegenerative diseases such as Alzheimer's or Parkinson's disease.

Biomarker breakthrough could improve Parkinson's treatment

August 15, 2016
A new, non-invasive way to track the progression of Parkinson's disease could help evaluate experimental treatments to slow or stop the disease's progression.

Serum iron levels may be causally associated with Parkinson's disease risk

June 4, 2013
Increased iron levels may be causally associated with a decreased risk of developing Parkinson's disease, says a new paper published this week in PLOS Medicine. Irene Pichler from EURAC in Italy and a group of international ...

New approaches to understanding Alzheimer's and Parkinson's disease

July 26, 2016
In a study presented today at the Alzheimer's Association International Conference 2016, researchers at the Douglas Mental Health University Institute have explored how some people may develop the hallmarks of Alzheimer's ...

Parkinson's study could pave way for early detection test

August 29, 2016
A test that can detect Parkinson's disease in the early stages of the illness has moved a step closer.

Uncovering the underlying causes of Parkinson's disease

April 3, 2014
(Medical Xpress)—A breakthrough investigation by UTS researchers into the underlying causes of Parkinson's disease has brought us a step closer to understanding how to manage the condition.

Recommended for you

Parkinson's is partly an autoimmune disease, study finds

June 21, 2017
Researchers have found the first direct evidence that autoimmunity—in which the immune system attacks the body's own tissues—plays a role in Parkinson's disease, the neurodegenerative movement disorder. The findings raise ...

Predicting cognitive deficits in people with Parkinson's disease

June 20, 2017
Parkinson's disease (PD) is commonly thought of as a movement disorder, but after years of living with PD approximately twenty five percent of patients also experience deficits in cognition that impair function. A newly developed ...

Pre-clinical study suggests Parkinson's could start in gut endocrine cells

June 15, 2017
Recent research on Parkinson's disease has focused on the gut-brain connection, examining patients' gut bacteria, and even how severing the vagus nerve connecting the stomach and brain might protect some people from the debilitating ...

Hi-res view of protein complex shows how it breaks up protein tangles

June 15, 2017
Misfolded proteins are the culprits behind amyotrophic lateral sclerosis (ALS), Alzheimer's disease, Parkinson's disease, and other neurodegenerative brain disorders. These distorted proteins are unable to perform their normal ...

CRISPR tech leads to new screening tool for Parkinson's disease

June 5, 2017
A team of researchers at the University of Central Florida is using breakthrough gene-editing technology to develop a new screening tool for Parkinson's disease, a debilitating degenerative disorder of the nervous system. ...

Infection with seasonal flu may increase risk of developing Parkinson's disease

May 30, 2017
Most cases of Parkinson's have no known cause, and researchers continue to debate and study possible factors that may contribute to the disease. Research reported in the journal npj Parkinson's Disease suggests that a certain ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.