Research in nonhuman primates is opening the possibility of testing treatments for the early stages of Alzheimer’s and similar diseases, before extensive brain cell death and dementia set in. A study published in Alzheimer’s & Dementia shows up to a six-month window in which disease progress could be tracked and treatments tested in rhesus macaques.
“This is a very powerful translational model to test interventions that target the tau protein,” said John H. Morrison, professor of neurology at the University of California, Davis and California National Primate Research Center and corresponding author on the paper.
The tau protein is found in neurons in the brain. The spread of misfolded tau through the brain is implicated in Alzheimer’s disease, frontotemporal dementia and other dementias. In Alzheimer’s, misfolded tau disrupts multiple processes essential for normal brain cell functioning. As the misfolded proteins spread, they affect neurons throughout the connected regions of the cortex that are crucial for memory and cognition.
The sick neurons then cause an inflammatory response mediated early on by microglial cells. Eventually, neurons die, leaving neurofibrillary tangles of tau protein, one of the key markers of Alzheimer’s and other dementing illnesses.
Thanks to advances in brain imaging, the discovery of biomarkers in human serum and cerebrospinal fluid, and work in rodent models, we now know more about the early stages of Alzheimer’s. But it is still difficult to figure out how tau, inflammation and disease progression relate to each other.
By UC Davis
Article can be accessed on: MedicalXpress