Using newly developed brain imaging technology, new research suggests that measuring the cumulative level slotting of a protein called tau can predict future neurodegenerative diseases associated with Alzheimer’s disease (AD),media New Atlas reported. The findings promise to accelerate clinical trial research and provide a novel way to predict disease progression before major symptoms appear.
For researchers, the exact changes that occur in the human brain at the earliest stages of Alzheimer’s disease remain a mystery. Although studies have looked at several signs of Alzheimer’s disease, it is not clear what the initial cause of the disease is. Scientists are trying to find effective drugs and treatments to slow or prevent the disease.
Most Alzheimer’s researchers agree that the two main pathological signs are the accumulation of amyloid and tau proteins in the brain. Abnormal aggregation of amyloid protein (known as plaque) is generally considered to be the main disease-causing mechanism for Alzheimer’s disease. A large number of misfolded tau proteins were also found in the disease, forming so-called neuroprogenite fibrous tangles.
So what is the first one? Amyloid protein plaques or tau tangles? For years, the issue has been the source of debate among researchers. The overwhelming consensus is that amyloid protein aggregates appear before tau tangles. One researcher even used the analogy of tau as a bullet, but amyloid protein is the trigger, and its plaques activate tau into a toxic state.
After years of failed clinical trials of drugs for these amyloid and tau aggregates, a growing number of researchers are looking further into the area of potentially undiscovered causal mechanisms behind Alzheimer’s disease. However, the link between the accumulation of these two proteins and neurodegenerative change sits still undeniable, and one of the challenges facing researchers is the inability to clearly measure the accumulation of these toxic proteins in living organisms.
“No one doubts that amyloid protein works in Alzheimer’s disease, but more and more tau finds that it’s beginning to change people’s perceptions of the real cause stoic,” explains Ren Laaud Joie, lead author of the new study. “However, looking at the brain tissue after death alone, it is difficult to prove that tau tangles cause brain degradation, not the other way around.” One of the team’s main goals is to develop non-invasive brain imaging tools that allow us to see if the location of the disease’s early tau build-up indicates later brain degeneration. “
Positron-emission computer tomography (PET) is one of the best tools researchers can currently use to image the accumulation of different proteins in the brain. Until recently, it was almost impossible to clearly identify tau aggregations in the brains of living people, but the recently developed PET spectre flortapiruci changed the “rules of the game”.
Over the past few years, researchers have increasingly found that flortaucipir PET imaging can effectively measure tau levels in living patients. The breakthrough subsequently led to studies to study the levels of tau in the brain at the earliest stages of Alzheimer’s disease. Now, for the first time, researchers can assess the question of whether to have chicken first or egg first. Scientists at the University of California, San Francisco, suggest that tau levels are effectively earlier than Alzheimer’s disease-related neurodegeneration.
The new study recruited 32 subjects with early-stage symptomalzheimeradisease. Each subject underwent two PET imaging tests about 15 months apart to track amyloid and tau protein levels in the brain. The main goal is to assess whether amyloid or tau protein can better predict subsequent brain atrophy and disease progression.
Gil Rabinovici, head of PET imaging programating at the UCSF Memory and Aging Center, said: “The match between tau diffusion and changes in the brain the following year is truly shocking. Tau PET imaging can predict not only how much atrophy we will see, but also where it will occur. These predictions are much more powerful than anything we do with other imaging tools, and further demonstrate that tau is the main driver of the disease. “
Unfortunately, this new finding will not translate directly into a wide range of clinical diagnostic applications. This PET imaging is expensive and time-consuming, so doctors can’t easily deploy it as part of a routine health check. But for researchers, the findings could go a long way toward accelerating clinical trials into potential new drug treatments.
“Tau PET could be an extremely valuable precision medicine tool in future clinical trials,” Rabinovici said. The ability to sensitively track tau accumulation in living patients will enable clinical researchers to seek for the first time specific patterns that can slow or even prevent each patient’s expected brain atrophy. “
The new study is published in the journal Science Translational Medicine.