A New Theory
The Week reports that scientists at the Krembil Brain Institute in Toronto are working on a new theory about the origins of Alzheimer’s disease. The Toronto team is basing this theory on thirty years of research. The team believes AD is an immune system disorder within the brain.
The immune system in the brain is similar to the body’s immune system. If a person had a head injury, the immune system in his brain aids in its repair. The same applies to bacteria in the brain. The immune system steps in to join the fight against the bacteria.
The New Theory Explained
Could AD be an autoimmune disease? The researchers no longer suspect, as determined previously, that beta-amyloid protein is abnormally produced. The new theory is that it is a normal molecule and part of the immune system in the brain.
For example, looking at the situation in a new light, when trauma to the brain, or bacteria exists, beta-amyloid is part of the brain’s immune response. Contrary to years of research, beta-amyloid does not appear later; it is already there when the problems begin.
An Understandable But Dangerous Error
There are similarities between fat molecules in bacteria and brain cell membranes. This similarity causes beta-amyloid to occasionally attack the brain cells in error, whereas the beta-amyloid should be protecting the brain cells.
The result is a loss of normal brain-cell function and eventually dementia.
Looking at these findings, that the attack on the immune system is indeed an error, the picture of an autoimmune disease emerges.
Other Theories About AD
Molecular Psychiatry published a study this week about researchers identifying a new gene that encodes for a microprotein named SHMOOSE. They analyzed the mutated protein and discovered that there is a connection with increased risk of AD, atrophy of the brain, and changes in energy metabolism.
Another theory is that mitochondria may be responsible for AD. Mitochondria have been called the energy factories in brain cells. Oxygen, glucose, and even the air we breathe are converted into energy and impact our memory and the way we think.
Other scientists claim that AD may originate from an infection in the brain. While still others put the blame on excessive metals in the brain such as copper, iron, or zinc.