Tag Archives: cell

New Hope To Fight Alzheimer’s

It is known that the onset of Alzheimer’s disease (AD) is associated with the accumulation of Amyloid beta () peptides in small molecular clusters known as oligomers. These trigger the formation of so-called ‘neurofibrillary tangles’ within neurons hamper their workings, ultimately causing cell death and so significant cognitive decline. Very large Aβ oligomers which form plaques outside neurons, alongside neuroinflammation have also been found to play a key part in the progression of the disease.

The EU-funded iRhom2 in AD project took as its starting point the protein iRhom2, which has been identified as a genetic risk factor for AD due to its pro-inflammatory properties. The team were able to explore further the influence of iRhom2 on neuroinflammation in mice. iRhom2 recently emerged as a protein of note in AD as it aids the maturation of an enzyme called TACE (tumor necrosis factor-α converting enzyme) guiding it towards a cell’s plasma membrane where the enzyme releases a cell-signalling cytokine (TNFα), implicated in the regulation of inflammatory processes. While mice studies have shown that TNFα-dependent inflammation can lead to sepsis and rheumatoid arthritis, it is also thought that the process contributes to neuroinflammatory signalling events, which can cause harm in the brain.

The EU-funded iRhom2 in AD project worked with mice that are prone to develop the hallmarks of AD, amyloid plaques and memory deficits. The team genetically altered iRhom2 in the mice then analysed the progression of the pathology using an array of biochemical and histological methods, together with a number of behavioural tests to assess cognitive decline. The results were somewhat surprising.

We initially hypothesised that iRhom2 would affect one specific aspect of neuroinflammation in AD. What we discovered was even more exciting as it actually affects several different aspects of neuroinflammation simultaneously. So modulating iRhom2 appears particularly well suited to interfere with AD,” explains project coordinator Prof. Dr. Stefan Lichtenthaler.

Source: https://cordis.europa.eu/

Brain Metals Drive Alzheimer’s Progression

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 including the University of Warwick.

Iron is an essential element in the brain, so it is critical to understand how its management is affected in Alzheimer’s disease. The advanced X-ray techniques that we used in this study have delivered a step-change in the level of information that we can obtain about iron chemistry in the amyloid plaques. We are excited to have these new insights into how amyloid plaque formation influences iron chemistry in the human brain, as our findings coincide with efforts by others to treat Alzheimer’s disease with iron-modifying drugs,” commented Dr Joanna Collingwood, from Warwick’s School of Engineering, who was part of a research team which characterised iron species associated with the formation of amyloid protein plaques in the human brainabnormal clusters of proteins in the brain. The formation of these plaques is associated with toxicity which causes cell and tissue death, leading to mental deterioration in Alzheimer’s patients.

They found that in brains affected by Alzheimer’s, several chemically-reduced iron species including a proliferation of a magnetic iron oxide called magnetite – which is not commonly found in the human brainoccur in the amyloid protein plaques. The team had previously shown that these minerals can form when iron and the amyloid protein interact with each other. Thanks to advanced measurement capabilities at synchrotron X-ray facilities in the UK and USA, including the Diamond Light Source I08 beamline in Oxfordshire, the team has now shown detailed evidence that these processes took place in the brains of individuals who had Alzheimer’s disease. They also made unique observations about the forms of calcium minerals present in the amyloid plaques.

The team, led by an EPSRC-funded collaboration between University of Warwick and Keele University – and which includes researchers from University of Florida and The University of Texas at San Antonio – made their discovery by extracting amyloid plaque cores from two deceased patients who had a formal diagnosis of Alzheimer’s. The researchers scanned the plaque cores using state-of-the-art X-ray microscopy at the Advanced Light Source in Berkeley, USA and at beamline I08 at the Diamond Light Source synchrotron in Oxfordshire, to determine the chemical properties of the minerals within them.

Source: https://warwick.ac.uk/