A local support group member forwarded me this terrific article in the Wall Street Journal today on cognitive impairment that occurs in Parkinson’s Disease. The article is a high level survey of Parkinson’s-related and protein-related research going on at the University of Washington (Seattle).
The article also talks about Alzheimer’s Disease a fair amount. The protein involved in the “tangles” of Alzheimer’s is tau. This tau protein abnormally accumulates in PSP and CBD.
Here are some excerpts:
* With Alzheimer’s disease, the patient often stops recognizing family. “With Parkinson’s, it’s like the family doesn’t recognize [the patient] anymore,” says Thomas Montine, a neuropathologist…
* Medical experts are increasingly recognizing the disease’s impact on cognition but research has been slow, in part because of the difficulty in sorting out the disease’s movement issues from the cognitive ones…
* One question is whether Parkinson’s patients with cognitive impairment simply have Alzheimer’s as well, or whether the deficits are caused by a different process in the brain.
* In a recent study at the University of Washington, Dr. Montine’s group studied 345 participants who were a mix of healthy volunteers, Parkinson’s patients with cognitive symptoms and those without such symptoms, as well as people with Alzheimer’s. … The data…suggest that classic Alzheimer’s pathology isn’t responsible for the cognitive deficits in most people with Parkinson’s. But the overlap suggests that treatments for Alzheimer’s could potentially be beneficial for Parkinson’s as well, according to Dr. Montine.
* Another question the University of Washington group is examining is whether cognitive decline is linked to low levels of the brain chemical dopamine, or whether it is the due to the loss of the dopaminergic neurons, which makes other substances in addition to dopamine.
* Dr. Montine’s group is also working on figuring out a better way to detect the presence of Lewy bodies. If the clumps could be detected in the blood or brain of a living person by a biological marker on, say, a brain scan or a blood test, the disease could be detected earlier—possibly even before symptoms show up—and its progression could be tracked…
* [Researchers] are studying the spinal fluid of patients who are known to have passed away from Parkinson’s and had Lewy bodies present in the brain. They have collected a list of promising markers—such as a protein called alpha-synuclein—that appear to denote the presence of these deposits. They are getting ready to start testing a way to tag these biomarkers in living patients to see if the presence of these markers in brain scans tracks with the progression of the disease.
Here’s a link to the WSJ article (available for free at present).
In the Lab
Wall Street Journal
August 10, 2010
How Parkinson’s Alters the Brain
Researchers Trace Clues to the Disease’s Effects on Patients’ Mental Ability
By Shirley S. Wang
Diseases of the Brain: Progressive conditions affect the body and mind in different ways
Cognitive: Memory loss and deterioration in thinking and planning functions
Physical: In mid-stage, disease could include slowness, rigidity and tremors
Inside the brain
The cortex, particularly the hippocampus, key to memory, shrinks.
Ventricles (fluid-filled spaces within the brain) enlarge.
Plaques (amyloid deposits) cluster between neurons.
Tangles (twisted proteins) are found within neurons.
Cognitive: Loss of executive functions, including planning, decision-making and controlling emotions.
Physical: Tremors, stiffness and slowed movements.
Inside the brain
Cells shrink in the substantia nigra, where dopamine is produced.
Lewy bodies (clusters of alpha-synuclein protein) accumulate inside neurons.
Sources: Alzheimer’s Association, Parkinson’s Disease Foundation and helpguide.org