I recently spoke with Australian researchers at the Florey Institute of Mental Health and Neuroscience who are working on a potential blood test to detect Alzheimer’s disease biomarkers. It might seem strange that researchers are focusing on developing diagnostic tools for dementia without any potential disease modifying therapies on the horizon, but after chatting with the researchers from Florey, they certainly put this research into some perspective.
Dr Blaine Roberts is a blood protein chemist, which means he spends his days looking for markers in the blood associated with disease pathology. He explained the point of his research quite simply by saying:
“With Alzheimer’s disease we don’t have that cholesterol test yet or that blood pressure test yet, and that is really what we are trying to get.”
He went on to say that the point of a blood test wouldn’t be to tell someone they have Alzheimer’s disease, as the point of a cholesterol test isn’t to tell you that you have cardiovascular [heart] disease. An Alzheimer’s blood test would be a screening tool which could be used by doctors to refer you on to a neuropsychologist (if required) and also offer advice on how to potentially change your lifestyle to reduce your risk of dementia and if this eventuates, to offer therapeutic strategies which may be able to minimise the damage that Alzheimer’s disease pathology can do to the brain.
I found this an interesting discussion and you can listen to it in full podcast at http://dementiaresearchfoundation.org.au/listen (Episode 26).
What about a treatment though? Are we getting any closer? Well while it is all still very preliminary, there was some interesting research out of the UK recently which noted that a compound called ‘Brichos’, can be effective at inhibiting the mechanisms which trigger the aggregation of the amyloid beta proteins, a major hallmark of Alzheimer’s disease. However, while this compound has been shown to prevent the accumulation of amyloid beta proteins, there is no evidence that it can remove or break down the amyloid beta plaques once developed. At this point in time, further rigour is required to develop techniques to diagnose Alzheimer’s disease and other forms of dementia at an earlier stage.
So what is Brichos? It is part of a set of compounds known as ‘chaperone’ proteins, which evolve to help other proteins fold or unfold to prevent protein aggregation.
According to the Cambridge University Press Release:
“Brichos sticks to threads made up of malfunctioning proteins, called amyloid fibrils, which are the hallmark of the [Alzheimer’s] disease. By doing so, it stops these threads from coming into contact with other proteins, thereby helping to avoid the formation of highly toxic clusters that enable the condition to proliferate in the brain.”
I’ll keep you posted about any further research in this area. To finish off this month’s research wrap up, I want to highlight another great study out of the USA which is really putting its own twist on the way we currently look at dementia research. The study known as ‘SuperAgers’ aims to better understand and identify factors that contribute to SuperAging – the maintenance of cognitive functioning in older age. To qualify as a SuperAger, participants had to score a certain level on a variety of mental tests, undertake periodic brain scans and medical tests, and agree to donate their brains after death. Over 400 people registered for the study, with only 35 meeting the requirements to be considered a SuperAger. This study has been ongoing since 2007.
So what is special about SuperAgers? The latest results, published in the Journal of Neuroscience, gave us some more insight. Using MRI brain imaging techniques, the researchers compared 31 SuperAger brains to 21 brains of a similar age and 18 brains aged in their 50s and 60s. As part of the trial, post-mortem analysis of five of the ‘SuperAger’ brains was also conducted. Combining all the data, results revealed that ‘SuperAger’ brains had a significantly thicker region of the anterior cingulate cortex, a region of the brain indirectly related to memory through its influence on related functions such as cognitive control, executive function, conflict resolution, motivation and perseverance. It was also noted that ‘SuperAger’ brains had significantly fewer neurofibrillary tangles (twisted fibres consisting of the Tau protein which cause brain cell death) and a large supply of a specific brain cell called ‘von Economo’, which are linked to higher social intelligence.
It is the hope that the ‘SuperAgers’ study will create a better understanding around why some people may not get dementia in later life and thus the researchers can develop a set of recommendations to advise the public on how to reduce your risk of dementia. The ‘SuperAgers’ study is still ongoing and I’ll keep you posted about further results. To find out more about the latest dementia research you can follow the Dementia News blog at http://dementiaresearchfoundation.org.au/blog and sign up via http://dementiaresearchfoundation.org.au/dementia-news
Author: Dr Ian McDonald