Alzheimer's A Distant Memory

Alzheimer's A Distant Memory

Two teams of Australian researchers have identified new approaches for the diagnosis and treatment of Alzheimer's disease (AD), which could potentially result in new and definitive ways to accurately determine the presence of the disease before more debilitating symptoms arise.

The diagnosis of AD is currently only possible via post-mortem examination of the brain for the disease's characteristic neuropathology. However, detecting and treating AD early is paramount to preventing it from causing widespread damage to the brain.

Speaking at The Royal College of Pathologists of Australasia's (RCPA) 11th annual Pathology Update conference at the Sydney Convention Centre in Darling Harbour, two teams of scientists announced the results of years of research, highlighting a range of possible biomarkers which could result in a new diagnostic and therapeutic approach to tackling the disease.

Dr Simon Laws, from Edith Cowan University and the Australian Imaging Biomarker and Lifestyle (AIBL) research group, announced two major findings from his studies. In the first study, Dr Laws revealed the successful identification of a panel of eight potential plasma biomarkers for the disease.

The results of the second study found that sex hormone levels, especially testosterone and luteinizing hormone, correlated with the presence of AD-causing plasma and cerebral amyloid-beta in the brain, which could lead to new methods of diagnosis and treatment.

Dr Laws says the identification and validation of a short panel of biomarkers has significant implications for the future diagnosis, prediction and monitoring of AD.

"The close association of hormones with AD pathology has significant implications on future treatments of the disease, with a clinical trial being the next stage in assessing the efficacy of this approach," says Dr Laws.

The second team, led by Dr Ashley Bush of the Department of Pathology and Mental Health Research Institute at the University of Melbourne, sought to explore how impairments to the brain's ability to export concentrations of transition metals like zinc, copper and iron correlate with the presence and formation of plaques, which could provide pathologists with new methods of diagnosis and treatment of AD.

"The brain utilises these metals for specialised neurochemistry and the synthesis of heme," says Dr Bush.
"But it is in this high flux environment that several of the culprit proteins of AD accumulate, losing function and possibly becoming toxic. These include amyloid-beta, which build up outside of the cell forming plaques and tau, which concentrate inside the brain cells forming tangles. Both pathologies capture high concentrations of metal ions."

The levels of these ions in the brain rise with aging and rise even more as the symptoms of AD set in. The abnormal regulation of metals in the brain is key to the formation of AD-causing plaques and tau.

"These recent discoveries concerning the metal-centred neuropathology of AD are the target for a new class of drugs which have shown considerable promise in clinical trials. These abnormalities are also reflected in the periphery in AD and may be the basis for predictive biomarkers," says Dr Bush.

Royal College of Pathologists of Australasia: is the leading organisation representing pathologists in Australasia. Its mission is to train and support pathologists and to improve the use of pathology testing to achieve better healthcare.
For more information on Pathology Update, visit www.RCPA.edu.au