A new study, published in the journal Neuron, examined the accumulation of tau ligands, also referred to as PBBs, in the brains of living patients with Alzheimer’s disease.  The researchers also examined the patterns of tau ligand presence in the brains of living patients without Alzheimer’s disease as well as in animal models of these disorders.  Mice models were the primary animal model utilized in this study.  Using a PET scan, they found certain regions rich in tau in patients with Alzheimer’s disease.

In an analysis of the study, BBC News describes this work as “pioneering.”  The technique of in vivo brain scans, or brain scans conducted while the patient is still alive, could help develop novel ways of diagnosing and treating dementia.  Though this study does not specifically consider other conditions, it is conceivable that refining the technique could also be beneficial for patients suffering from other neurological conditions and brain disorders.

Specifically, in this research, the scientists developed a chemical that was capable of binding to tau.  Then, using in vivo brain scans, the researchers could locate the areas of the brain in which the chemical existed in a higher volume.  This study may result in the first reliable diagnostic test for Alzheimer’s disease and may even allow it to be diagnosed earlier.  After a patient is diagnosed, a doctor may be able to use this method to monitor progress.  If the drug reduces the presence of tau in the brain, it could be an indication that the Alzheimer’s is in remission or its progression has been stunted.

Currently, there are drugs that are in development that specifically target tau.  These scans will both evaluate their efficacy as well as aid in their clinical use.  Alzheimer’s Research UK has described this work as promising, likely because of its potential in assessing risk, diagnosing Alzheimer’s disease, developing treatment alternatives, and enhancing and evaluating treatments currently being used.

According to an earlier National Monitor article, the majority of researchers believe two proteins are responsible for the Alzheimer’s disease: tau and beta-amyloid.  In particular, these two proteins are thought to disrupt signaling between neurons during the aging process, as well as killing these proteins.  Additionally, a new study published in the Journal of Alzheimer’s Disease suggests a new possibility for the cause: accumulation of iron.  While more work is needed to reconcile the variety of findings related to the cause of Alzheimer’s, these studies provide critical insights for a developing field.