While conducting the study, the researchers observed the donated tissue from 37 patients, they found that neurons of some patients with Alzheimer’s disease had both types of tau, while others had only the fragmented tau.
Scientists at UC San Francisco have found that a relatively unstudied form of the tau protein associated with neurodegeneration may be a way for the better diagnosis and treatment of the diseases like Alzheimer’s. The findings of the study were published in Neuropathology and Applied Neurobiology.
According to the scientists, it is possible that the form of tau, which is broken into fragments that accumulate in the brains of people with Alzheimer’s, is responsible in the degenerative progression associated with the condition. However, it is distinct from other tau accumulations that have been the focus of earlier drug development.
“This work really opens our eyes to an important pathogenic process in Alzheimer’s disease that hasn’t been given much attention,” said neuropathologist Lea T. Grinberg, MD, PhD, who co-led the study with Michelle Arkin, PhD, chair of Pharmaceutical Chemistry.
Grinberg said that a “huge” number of neurons within toxic tangles of accumulated tau include these tau fragments. Reportedly, researchers have long known that another type of tau, called phospho-tau, is present in neurons affected by Alzheimer’s disease. However, efforts to target this type of tau with drugs have thus far been unsuccessful.
Meanwhile, the scientists were able to assess tau in human brains thanks to UCSF’s Neurodegenerative Disease Brain Bank. While conducting the study, the researchers observed the donated tissue from 37 patients, they found that neurons of some patients with Alzheimer’s disease had both types of tau, while others had only the fragmented tau.
Additionally, the abundance of fragmented tau observed in patients who had Alzheimer’s and Pick’s disease was barely seen in patients with other forms of dementia that involve abnormal tau function, Grinberg said, meaning that detection of fragmented tau may help distinguish between dementias in living patients, which is not currently easy to do.
The researchers also revealed that this study gives a better idea of how these drugs can be used to treat Alzheimer’s, to develop better diagnostic tests, and identify other neurodegenerative diseases.