Getting your appendix removed may reduce the risk of developing Parkinson’s disease, researchers report yesterday (October 31) in Science Translational Medicine. The team identified the link between the surgery and the neurodegenerative disease in health data from 1.6 million Swedes.
When analyzing tissue from healthy individuals in the dataset, the investigators found that their appendix tissue had protein clumps similar to those seen in the brains of patients with Parkinson’s disease. The finding suggests the appendix plays an early role in the disease through this same protein accumulation, the scientists say. These proteins contribute to Parkinson’s somehow, so an appendectomy may prevent their negative activity.
“It plays into this whole booming field of whether Parkinson’s possibly starts in the gut,” Per Borghammer, a neuroscientist at Aarhus University in Denmark who was not involved in the study, tells Science. “And that would be a radical change in our understanding of the disease.”
Study coauthor Viviane Labrie, an assistant professor at the Van Andel Research Institute in Michigan, doesn’t go quite as far, telling CNN the disease is a multisystem disorder, “so there's likely to be many sites of origin in terms of where Parkinson's disease starts, the [gastrointestinal tract] being one of them. For other people, it may begin in the brain.”
Symptoms of the disease can show up in the gut earlier than in the brain, so to understand why, Labrie and her colleagues looked at the appendix—once considered useless but now thought to play a role in the immune system by scanning for infectious pathogens. The health data of the Swedish cohort showed a 19-percent drop in the risk of developing Parkinson’s disease if individuals had an appendectomy. In an additional test, the researchers found that 46 out of 48 samples of healthy individuals’ appendix tissue had clumps of alpha-synuclein—a protein build-up found in the brains of Parkinson’s patients.
“We’re not saying to go out and get an appendectomy,” Labrie tells The Washington Post. Many people with their appendix intact don’t develop Parkinson’s disease. Instead, she tells Science, she hopes the work might help researchers better understand why the synthesis of alpha-synuclein goes awry and why it builds up in the gut and the brain.