Nanoparticles for the detection of Alzheimer's disease through magnetic resonance imaging

July 12, 2018, Universidad Politécnica de Madrid
Brain section of a transgenic mouse for AD showing accumulations of amyloid plaques (green) and ferritin (red). Credit: ACS Chem. Neurosci., 2018, 9 (5), pp 912–924

UPM researchers are involved in the development of a new biosensor that can be useful to achieve an early non-invasive diagnosis of Alzheimer's disease using magnetic resonance imaging.

The presence of deposits in the brain is a histopathological characteristic of patients with Alzheimer's . Thus, a team of researchers from diverse institutions, led by Milagros Ramos from the Centre for Biomedical Technology (UPM), has developed a new contrast agent for imaging resonance magnetic based on functionalized magnetic nanoparticles that could work as a biomarker for an early of this disease.

This result can pave the way for new studies that develop methods of early and non-invasive diagnosis of this neurodegenerative disease.

Alzheimer's disease is a that affects about 47 millions of people worldwide. Today, the definitive diagnosis of this disease is only possible after the death of the patient, when we can determine the presence of tangles and located in the brain parenchyma through histological techniques.

The current diagnostic practices include evaluations of the patient history to detect behavior changes and neuropsychiatric and neuroimaging evaluations that provide a probable diagnosis of the Alzheimer's disease.

Today, biomarkers provide neither a high accuracy of early diagnosis of the disease nor a suitable monitoring of the progress of the disease after using radioisotopes. Therefore, researchers are currently searching for new biomarkers that detect the presence of Alzheimer's disease using non-invasive methods.

Magnetic resonance imaging has better spatial resolution than the positron emission tomography (PET) and, in addition, it does not use radiotracers.

The presence of iron deposits in the brain is a histopathological characteristic of patients with Alzheimer's disease. However, the need for high concentration of accumulated iron and the extended periods of time to obtain the images make it difficult to use this technique in patients for the early detection of this disease. In this way, it seems necessary to develop contrast agents that allow us to achieve greater sensitivity in magnetic resonance for the detection of incipient iron accumulation associated with amyloid plaques in the brain of patients with Alzheimer's disease.

In order to make progress in the search of non-invasive biomarkers for an early detection of the Alzheimer's disease, Dr. Milagros Ramos from CTB-UPM has led a team of researchers from Severo Ochoa Molecular Biology Center (UAM-CSIC), Universidad Carlos III, Gregorio Marañón Health Research Institute (IiSGM) and CIBER of Mental Health (CIBERSAM) and CIBER of Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN).

The study describes the presence of accumulated iron and the protein that stores iron (ferritin) in a hippocampal area of transgenic mice for Alzheimer's disease. These accumulations of iron and ferritin are observed around the amyloid plaques which are characteristics of the disease.

This finding helped develop a contrast agent for based on the functionalization of magnetic particles with an antibody that recognizes ferritin. Thus, researchers showed that, through histological analysis, the new nanoconjugate binds to the ferritin accumulation in a particular way in transgenic mice for the Alzheimer's disease.

Milagros Ramos explains, "the accumulation of functionalized nanoparticles in the specific area cause a significant decrease in certain values obtained through magnetic resonance, this indicates that the new contrast agent can be useful in the future for an early and non-invasive diagnosis of this pathology through magnetic ."

Explore further: Alzheimer's breakthrough: Brain metals that may drive disease progression revealed

More information: Tamara Fernández et al. Functionalization and Characterization of Magnetic Nanoparticles for the Detection of Ferritin Accumulation in Alzheimer's Disease, ACS Chemical Neuroscience (2018). DOI: 10.1021/acschemneuro.7b00260

Related Stories

Alzheimer's breakthrough: Brain metals that may drive disease progression revealed

June 21, 2018
Alzheimer's disease could be better treated, thanks to a breakthrough discovery of the properties of the metals in the brain involved in the progression of the neurodegenerative condition, by an international research collaboration ...

Physicists link specific iron forms to Alzheimer's

May 8, 2018
There have been indications for decades that there is a link between increased iron levels in the brain and Alzheimer's disease. Leiden physicists now report a distinction between different forms of iron, identifying specific ...

Team develops world-first array of compounds for detection, imaging of Alzheimer's disease

January 5, 2018
Hong Kong Baptist University (HKBU) chemists have invented a new class of multifunctional cyanine compounds that can be used for detection, imaging and treatment of Alzheimer's disease. The research team was jointly led by ...

The onset of Alzheimer's disease: The importance of family history

February 26, 2018
You're about to turn 60, and you're fretting. Your mother has had Alzheimer's disease since the age of 65. At what age will the disease strike you? A Canadian study published in JAMA Neurology shows that the closer a person ...

Recommended for you

Amyloid pathology transmission in lab mice and historic medical treatments

December 13, 2018
A UCL-led study has confirmed that some vials of a hormone used in discontinued medical treatments contained seeds of a protein implicated in Alzheimer's disease, and are able to seed amyloid pathology in mice.

Study links slowed brainwaves to early signs of dementia

December 13, 2018
To turn back the clock on Alzheimer's disease, many researchers are seeking ways to effectively diagnose the neurodegenerative disorder earlier.

New discoveries predict ability to forecast dementia from single molecule

December 11, 2018
Scientists who recently identified the molecular start of Alzheimer's disease have used that finding to determine that it should be possible to forecast which type of dementia will develop over time—a form of personalized ...

Researchers classify Alzheimer's patients in six subgroups

December 5, 2018
Researchers studying Alzheimer's disease have created an approach to classify patients with Alzheimer's disease, a finding that may open the door for personalized treatments.

Neuroscientists pinpoint genes tied to dementia

December 3, 2018
A UCLA-led research team has identified genetic processes involved in the neurodegeneration that occurs in dementia—an important step on the path toward developing therapies that could slow or halt the course of the disease. ...

Detecting signs of neurodegeneration earlier and more accurately

November 30, 2018
Signs of neurodegenerative diseases, appearing years before the emergence of clinical manifestations, can be detected during the examination of medical samples by means of fluorescence microscopy by using new sensitive and ...

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.