The early stages of Alzheimer’s disease can be detected with a simple eye test, according to studies recently completed in the U.S. and Australia. At present, there is still no cure for the condition, and the cause is still not fully understood, but it is believed to result from factors that include the environment and lifestyle. A minor contribution is also believed to be genetic changes that affect the brain.
Using two different techniques, researchers were able to identify a beta-amyloid protein bio-marker in the lens and the retina of the eye. The researchers hope that the techniques, which provides a high degree of accuracy, can become part of the regular eye exams that are performed by opticians. They were able to differentiate volunteers who were most likely to be Alzheimer’s disease sufferers from those were not, and expect that the test, when properly conducted can become a critical component in the diagnosis and treatment of the disease.
The brains of Alzheimer’s patients will usually have fewer cells and connections than healthy brains. The beta-amyloid protein, forms clumps in the brain leading to damaged brain cells, and the presence of these plaques disrupts the cell-to cell communication. They are also likely to shrink in size as cells are not replaced.
Another hallmark of the disease that researchers have noticed is abnormal twisted tangles of a protein, known as tau, that is needed for the transportation of nutrients to the brain cells. The normal shape and function of the protein usually includes a long, narrow extension, which are twisted in Alzheimer’s disease patients. The tangled tau negatively affects transportation of nutrients, leading to further degradation and death of brain cells.
The detection of Alzheimer’s disease with the eye test is only one of a series of recently announced advances that have been made in treating the disease. Researchers at the Mayo Clinic have also discovered a protein called TDP-43 in the brain, which may also be linked to the disease. When the protein is no longer functioning as normal, symptoms of Alzheimer’s begin to appear. The discovery of the protein can lead to developing a test with which it can be identified, and then targeted with specific drugs, in much the same manner as other diseases are combated. The presence of the protein is an indication of the condition, but researchers cannot yet determine if the protein causes the disease or if the disease produces the protein, but the discovery offers a path that can be followed.
Previously, the correct diagnosis of Alzheimer’s was made by examining the brains of patients after death, but now Dr. Keith Josephs, who is one of the lead authors of the study says that discovery of the protein opens several different paths that research can take. Along with the early detecting of Alzheimer’s with the eye test, and the discovery of the proteins that may be linked to the disease, there now appears to be more hope. One of the next steps is to examine patients who are thought to be in the early stages of the disease, and to find out where in the brain the proteins are located before treatment can begin.
By Dale Davidson