Pathological aging (PA) is used to describe the brains of people which have Alzheimer’s disease (AD)-like pathology but where the person showed no signs of cognitive impairment whilst they were alive.
New research shows that PA and AD brains contain similar amyloid β (Aβ) plaques and that while on average AD brains contain more Aβ there was considerable overlap in Aβ subtypes. These results suggest that PA may simply be an early stage of AD. It has been previously suggested that the Ab; plaques in PA are different and somehow less toxic than those in AD.
Researchers from University of Florida and Mayo Clinic, supported by the National Institute of Health, compared post-mortem brain tissue from people with AD, PA, and controls. When they looked at the type and amount of Ab; they found that while both AD and PA had elevated levels of Ab; on average levels were slightly lower in PA.
Further studies showed that there were really no major differences between the accumulated Ab in both AD and PA.
Dr Todd Golde, who coordinated the research commented that “While there might be some subtle differences in Ab, it seems that PA may represent an early stage of AD rather than a benign form of Ab deposition, and that if they live long enough people with PA will go on to develop AD.
We hope that understanding the differences between PA and AD will provide new ways to help protect the brain and promote the development of AD therapeutics.”
This work was published in BioMed Central’s open access journal Alzheimer’s Research & Therapy,