Alzheimer’s disease is the 6th leading cause of death in the country right now, affecting more than 5 million Americans. Scientists do not yet fully understand what causes Alzheimer’s disease, but do know it develops because of a complex series of events that take place in the brain over a long period of time. Until a very recent study it was thought that family history, genetics, and a person’s lifestyle were the only things that can shape the onset of the disease.
According to a recent study published in the October 4th, 2011 issue of the journal of “Molecular Psychiatry,” the brain damage that characterizes Alzheimer’s disease may start out in a form similar to that of an infectious disease. The University of Texas Medical School at Houston, led by professor of neurology Dr. Claudio Soto, performed a current study by exposing lab mice to human brain tissue of Alzheimer’s patients as well tissue from a non infected brain as a control.
None of the mice injected with the control showed any symptoms of Alzheimers, while all those injected with the Alzheimer’s brain extracts developed plaques and other brain changes associated with the disease.
“Our findings open the possibility that some of the sporadic Alzheimer’s cases may arise from an infectious process, similar to how mad cow disease arises from infection with diseased proteins called prions,” said Soto. “It involves a normal protein that becomes misshapen, and is able to spread by transforming good proteins to bad ones. The bad proteins accumulate in the brain, forming plaque deposits that are believed to kill neuron cells in Alzheimer’s.”
Soto and his team looked to Creutzfeldt-Jakob disease (CJD), the human form of mad cow disease, as a potential model for how Alzheimer’s may be contagious in humans. CJD is known to spread via contaminated food, blood transfusions, tissue transplants and other forms of surgery. If Alzheimer’s does in fact behave like CJD, Soto says that the spread will be dramatically reduced if the medical community screens blood more thoroughly and uses greater precautions during surgery.
Soto and other researchers involved in the study admit that the findings are very preliminary. It is unclear whether these same things could occur in people. Until results of the study with mice can be confirmed, Soto suggests that people continue to avoid well-known risk factors for Alzheimer’s disease, like high blood pressure, smoking and weight gain. No need to panic either as prions are not known to be transmissible through the air. Soto encourages the families of Alzheimer’s sufferers to continue to show affection and support. “We know that there is no risk to family members of people with prion diseases,” he told CBS News. “There are no cases of disease in relatives.”
