NEW TECHNIQUE SPEEDS UP SEARCH FOR ALZHEIMER'S CURE

A team of scientists, based jointly between the University of Lancaster and the University of Sheffield, have developed an exciting new technique for measuring the effects of Alzheimer's disease and the identification of new drug treatments. In addition, it is hoped that the technique may also be able to help diagnose Alzheimer's disease at an earlier stage.

The team have developed a sensitive new spectroscopy method for detecting interactions between proteins in solution, to see whether they are clumping together - an important sign that Alzheimer's disease is active. The build up in the brain of 'clumps' of a protein called ?-amyloid is thought to be a critical step in the events that lead to the death of nerve cells in Alzheimer's disease. In Alzheimer's disease, the ?-amyloid accumulates in the centre of the 'senile plaques' which are one of the characteristic pathological signs of the disease.

The teams at Lancaster and Sheffield have developed a novel technique called 'fluorescence anisotropy' to detect the very early stages of ?-amyloid fibre formation.

Dr David Allsop from Lancaster University's Biological Science department, the scientist in charge of the project, said: 'This sensitive technique can measure the rate at which the molecule 'spins' or 'tumbles about' in a liquid. This rate of motion varies according to the size of the molecules, with larger molecules moving more slowly than smaller ones. 'To look at fibre formation, we 'label' some of the molecules with a 'light-emitting' tag. These labelled molecules are then mixed with normal ones, and the mixture is then allowed to 'clump' into fibrils. As the size of the clumps increase, so they spin more and more slowly, and this change in molecular motion can be monitored by changes in the amount of light given off. The size of the aggregates can then be calculated from the rate at which they tumble about.'

The technique is now being used to test compounds and drugs that block protein clumping, and which might be able to slow or stop Alzheimer's disease. A number of novel compounds have been tested and so far, four compounds have been shown to be effective inhibitors, even at very low concentrations. This technique may also be sensitive enough to detect clumping proteins in human samples such as the spinal fluid that surrounds the brain, and so could form the basis of a clinical test to improve the diagnosis of Alzheimer's disease.

Dr Richard Harvey, director of research for the Alzheimer's Society said 'We are very pleased to be funding this exciting work which is now showing promising results. This project was selected for funding by our network of carers, former carers and people with dementia only 1 year ago, and is already delivering important results.'

Alzheimer's disease is the most common cause of dementia affecting over half a million people in the UK. The Alzheimer's Society is the leading care and research charity for people with all forms of dementia. A major part of our research strategy is to find the causes of dementia and develop effective treatments.