Alzheimer's and Parkinson's Biomarkers Make Headlines
Yesterday, two major news stories broke on the pursuit of biomarkers for neurodegenerative disease. One of the articles appeared in The New York Times and the other appeared in The Wall Street Journal. The Alzheimer's Disease Neuroimaging Initiative (ADNI), a multi-year clinical study, reported a simple and practical test to accurately predict who will develop Alzheimer's. Additionally, Parkinson's scientists reported leveraging Alzheimer's research to better understand the cognitive impairment seen in PD. Todd Sherer, PhD, the Foundation's vice president, research programs, discussed the implications of these outcomes for PD research and how the findings are bringing us closer to life-transforming treatments for Parkinson's disease.
Q: ADNI reports a simple test of cerebrospinal fluid (CSF) that predicts with 100-percent accuracy who will develop Alzheimer's disease. Why does early diagnosis matter if we don't have treatments that can stop the disease from getting worse?
A: It's vital to pursue biomarkers not just for earlier diagnosis but also because they are a key missing link in the development of new treatments that could actually slow or stop the progression of the disease. These are the life-transforming treatments that patients and their loved ones have already waited far too long to see materialize.
Q: Is any study like ADNI taking place in the Parkinson's field?
Yes. ADNI, which was launched in 2004, is the scientific model for our Foundation's Parkinson's Progression Markers Initiative (PPMI), a long-term clinical study seeking biomarkers of Parkinson's disease. The studies are similar in scale, duration and methodology. ADNI focused primarily on the Alzheimer's-implicated proteins beta amyloid and tau. PPMI is examining numerous PD biomarker candidates, including urate and the proteins alpha-synuclein and DJ-1 (as well as beta amyloid and tau, which may play a role in Parkinson's as well as in Alzheimer's) (see below).
It is incredibly encouraging to see a leap forward like this come out of ADNI after a relatively short six years. It only increases our confidence that PPMI will advance Parkinson's research to the same level in a similar timeframe.
Q: The other news this week has to do with possible overlaps between Alzheimer's and Parkinson's. According to an article in the Wall Street Journal about research at the University of Washington, significant numbers of PD patients with cognitive impairment had decreased amounts of amyloid in their spinal fluid, similar to Alzheimer's patients -- suggesting that treatments for Alzheimer's could be beneficial for Parkinson's as well.
We've funded Jing Zhang (University of Washington) since 2005. We'll continue to follow biomarker discovery at UW with interest, since this is exactly the kind of work that, if positive, could enter PPMI for further validation and verification. The goal would be to speed the discovery of treatments that exploit these targets to improve cognitive dysfunction in PD.
Speeding effective treatments for the cognitive aspects of Parkinson's has been a priority for The Michael J. Fox Foundation for several years. For example, in 2008, with support from EMD Serono, we launched a $2-million funding program to speed development of treatments for PD cognitive impairment.
Although cognitive issues in AD and PD manifest very differently, the links between their underlying pathology are fairly well characterized. One Alzheimer's drug, Exelon, has been approved to treat Parkinson's-related dementia. To increase understanding of the relationship between AD and PD-related dementia, PPMI will examine CSF for beta amyloid and tau (the key proteins implicated in Alzheimer's disease).