Alzheimer’s Disease is a progressive and irrevocable brain disease that destroys mental and physical functioning in humans, and perpetually leads to death. It is the fourth leading cause of adult death in the United States, affecting 2.5 to 3 million people each year. The cause has not yet been identified, nor has a cure been discovered, but research advances are being made. To fully understand and fight Alzheimer’s Disease, one must know how it affects the brain, which is the part of the body that it takes the largest toll on.
Autopsies on many Alzheimer’s disease sufferers show that there were significant differences between their brains and those of normal individuals. Specifically, there was a loss of nerve cells in the cerebral cortex of the Alzheimer’s victims, with approximately 10% of the neurons in this region being lost. However, it is important to note that this 10% loss is relatively minor and cannot fully account for the severe impairment suffered by Alzheimer’s victims.
Neurofibrillary tangles are found in the brain within the cell bodies of nerve cells in the cerebral cortex and take on the structure of a double helix. Other diseases that have double helixes include Parkinson’s disease, Down’s Syndrome, and Dementia Pugilistica. Scientists are not sure if the double helixes are related in these very different diseases. Neuritic plaques are patches of clumped material outside the bodies of nerve cells in the brain. They are mainly found in the cerebral cortex but have also been seen in other areas of the brain.
At the core of each of these plaques is a substance called amyloid, which is an abnormal protein not usually found in the brain. This amyloid core is surrounded by fragments of dead or dying nerve cells, including dying mitochondria, presynaptic terminals, and double helical filaments identical to those that form neurofibrillary tangles. Many neuropathologists believe that these plaques are clusters of degenerating nerve cells, but they are still unsure of how and why these fragments cluster together. The technical name given by neuropathologists is Congophilic Angiopathy.
To an abnormality found in the walls of blood vessels in the brains of victims of Alzheimer’s. These abnormal patches are similar to the neuritic plaques that develop in Alzheimer’s, in that amyloid has been found within the blood vessel walls wherever the patches occur. Another name for these patches is cerebrovascular amyloid, meaning amyloid found in the blood vessels of the brain.” Acetylcholine is a substance that carries signals from one nerve cell to another and is known to be important for learning and memory.
In the mid ’70s, scientists found that the brain of a person afflicted with Alzheimer’s Disease contained 60% to 90% less of the enzyme choline acetyltransferase (CAT), which is responsible for producing acetylcholine, than did the brain of a healthy person. This was a great milestone in the fight against Alzheimer’s, as it was the first functional change related to learning and memory, and not to different structures. Somatostatin is another means by which cells in the brain communicate with each other.
The quantities of this chemical messenger, like those of CAT, are also greatly decreased in the cerebral cortex and the hippocampus of Alzheimer’s victims, almost to the same degree as CAT is lost. Although scientists have been able to identify many of these and other changes, they are not yet sure as to how or why they take place in Alzheimer’s Disease. They are so near to completing the mystery of Alzheimer’s, but yet still so far away. If treatment is required for someone with Alzheimer’s Disease, the Alzheimer’s Disease and Related Disorders Association (ADRDA) should be contacted.
It is a privately funded, national non-profit organization dedicated to finding a cure and easing the burden of Alzheimer’s victims and their families. There are more than 160 chapters throughout the country and over 1000 support groups that can be contacted for help. ADRDA fights Alzheimer’s on five fronts: funding research, educating and increasing public awareness, establishing chapters with support groups, encouraging federal and local legislation to help victims and their families, and providing a service to help victims and their families find the proper care they need.
