Synchrotron pinpoints Alzheimer’s

Engineers are using a synchrotron to test for iron oxide associated with Alzheimer’s and other neurodegenerative diseases.

According to The Alzheimer’s Society, dementia affects over 750,000 people in the UK. Diagnosis is usually by a series of memory and mental state tests, and a specific cause is almost impossible to isolate in a living patient.

A new technique can pinpoint and identify the tiny iron oxide particles associated with Alzheimer’s and other neurodegenerative conditions, such as Hunter’s and Parkinson’s disease. It will provide new information for research into the cause of the diseases and could lead to the first diagnostic procedure for Alzheimer’s in patients while they are alive.

The team of researchers from the University of Florida and Keele University have based their investigation on the fact that regions of the brain affected with these diseases tend to contain unusually high concentrations of iron oxide and other iron-containing particles. The indicative form is hard to distinguish from iron naturally present in healthy brain tissue.

Traditional methods for detecting the presence of iron in the brain involve staining tissue samples, but this method does not narrow down the specific iron compound nor reveal how it binds to the affected tissue. Electron microscopes could identify the molecules, but their tight resolution makes it impossible to search enough area to find them.

To solve the problem, Mark Davidson and Chris Batich from the University of Florida’s materials science and engineering department, along with Albina Mikhaylova, Jon Dobson and Joanna Collingwood of Keele University, turned to the synchrotron at the US Department of Energy’s Argonne National Laboratory near Chicago.

The synchrotron, or Advanced Photon Source, is an electron accelerator that produces powerful X-rays. The team developed a system of mirrors and lenses that use one of the machine’s 35 X-ray sources to analyse brain tissue.

Whereas an electron microscope can examine tissue one micron in size, the new device can look at tissue samples of two or three hundred microns. If it locates a particle, it then uses traditional spectroscopic methods to zoom in and determine what sort of iron the particle is.

The researchers hope the study will give an insight into whether the iron is a cause or symptom of the disease. They are already planning to do experiments based on the research that could lead to using magnetic resonance imaging, or MRI, to highlight damaging iron in patients’ brains.

“If we can adjust the MRI to look for specific iron compounds related to Alzheimer’s we may be able to provide a technique for early diagnosis before clinical symptoms appear. The major advantage of this is that most treatments currently in development rely on early detection to slow or halt progression of the disease, as they cannot reverse it,” Davidson said.