Pathology of Alzheimer's Disease
There are many current theories as to what triggers the onset of Alzheimer's
Disease. There seem to be many contributing factors laying at the root of
this disease, and the acquisition of Alzheimer's seems to have both environmental
and genetic foundations. Regardless of the cause, the gross pathology of
Alzheimer's dementia remains the same: toxic levels of amyloid protein build
up in the brain, and destroy those regions next to the accumulation sites.
This particular section of our Alzheimer's Web Page will look more in depth
at the structure and production of amyloid protein in the brain of Alzheimer's
patients.
Dating back to Alois Alzheimer's 1907 initial description of the disease,
are the characteristic silk-like senile plaques and neurofibrillary tangles
and threads that accumulate within the gray matter of the cerebral cortex
and cerebral nerve cells of Alzheimer's patients. Composed of highly indigestible
amyloid fibers, Alzheimer's patients are unable to break these fibers down.
The accumulation of these fibers leads then to the production of the brain
lesions characteristic of Alzheimer's Disease (Glenner).
The plaques accumulate to neurotoxic levels, compressing those nerve fibers
that lie in their path, effectively destroying these regions of the brain
(Glenner). This destruction of cerebral tissue then causes the behavioral
changes that we associate with Alzheimer's dementia. In extremely progressed
cases, these amyloid fibers will aggregate around blood vessels, causing
a structural weakening to occur in the vessels and a subsequent leakage
of blood serum into the cerebral space. If leakage is great, intercerebral
hemorrhage and stroke are likely to occur (Glenner).
The following images were taken from a University
of Utah CNS Pathology Archive, and show what a researcher might find
after taking a section of brain from an Alzheimer's victim:
Neurofibrillary
Tangle
For more information the various types of plaques and tangles, and their implications in Alzheimer's disease, we suggest checking out the following
link:
The progression of Alzheimer's Disease hinges on these accumulations
of plaques and tangles and the subsequent cerebral degradation that follows.
Consequantly, this cerebral degredation then leads to the symptomolgy
expressed by Alzheimer's patients..
To find out more information about plaques, tangles and amyloid
protein, we invite you to check out a couple of really good links provided
by the Alzheimers Association Web Page. Don't forget to use your toolbar
to come on BACK here (there is not a link) once you've had your fill.
Welcome Back! As you have read, the presence and accumulation of amyloid
protein is central to the development of Alzheimer's. To truly begin to
understand Alzheimer's, then, we must look further at how this protein is
produced in our bodies. The following link will give you even more details
on amyloid protein .
Go on to the Genetic Aspects of
Alzheimer's
Look at Current Treatment Methods
for Alzheimer's
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