A simple infection in the early stages of life could trigger Alzheimer's disease in later life, according to research.
Swiss scientists studying chronic inflammation in mice found that a single infection during late pregnancy could be enough to prompt long-term neurological changes and trigger significant memory problems at old age.
Researchers from the University of Zurich said that the discovery could lead to new treatments and preventative therapies to stopping the mind-robbing disease before it develops.
Mice that were exposed to infection before birth had increased immune system signaling molecules associated with inflammation to the brain, according to the new study published in the Journal of Neuroinflammation.
Researchers explained that if the immune system challenge was repeated in adulthood, the effect was strongly exacerbated and resulted in changes similar to those seen in Alzheimer's patients.
Additionally, researchers found that mice genetically modified to produce a human version of the Alzheimer's-associated brain protein amyloid-beta had the worst neurological reaction to early infection.
Mice that were infected in the womb were predisposed to signs of Alzheimer's as they aged and performed less well on memory tasks and had changes in amyloid and tau, hallmark proteins of the disease in humans.
Researchers found that if a second viral infection was given later in life, the neurological changes became even more apparent and caused the disease to progress more rapidly.
"It seems likely that chronic inflammation due to infection could be an early event in the development of Alzheimer's disease," study leader Dr. Irene Knuesel, from the University of Zurich in Switzerland said in a statement.
If the recent findings are replicated in clinical trials, it would suggest that anti-inflammatory drugs could play a role in treating Alzheimer's disease.
“The results of this study suggest that repeated or severe infections may contribute to the development of Alzheimer’s disease in mice. While we know that the immune system plays a role in human Alzheimer’s disease, clinical trials with anti-inflammatory drugs have not yet shown conclusive benefits in treating the disease and so more research is needed to fit these pieces of the puzzle together," Dr. Marie Janson, from the charity Alzheimer's Research UK said in a statement.
“Understanding the risk factors for Alzheimer’s disease is essential, especially if some of these factors are things that we can actively change or avoid. This understanding can only come through research, yet research into dementia remains hugely underfunded. With around half a million people in the UK living with Alzheimer’s, and this number expected to increase, the need for this research has never been greater,” she added.