The appendix tends to get a bad rap. That long, narrow pouch extending off the digestive tract is notorious for getting infected, leading to emergency appendectomy surgery. A new study published in the journal Science Translational Medicine adds another flaw to the perplexing little organ: it might initiate the neurodegenerative disorder, Parkinson’s disease.
Researchers suggest that the appendix might also be the source for a protein called α-synuclein that has been implicated in Parkinson’s, reports Aimee Cunningham at ScienceNews. The team found the relationship when examining the medical records of 1.7 million Swedes, discovering that those who had their appendixes removed had a 19 percent reduction in odds of acquiring Parkinson’s.
When they looked at 48 samples of appendixes, the team found that 46 had clumps of a protein called α-synuclein, which is also found in the brains of Parkinson’s patients and is believed to be a main driver of the disease. When they looked at the case histories of 849 people with Parkinson’s, they determined that those who had the organ removed developed Parkinson’s 3.6 years later on average than those who still had the little sack.
It’s still not clear how the two are related. Hannah Devlin at The Guardian reports that it’s possible that Parkinson’s is triggered by an event in which the protein escapes the appendix and travels to the brain via the vagus nerve.
“There has to be some other mechanism or confluence of events that allows the appendix to affect Parkinson’s risk,” senior author Viviane Labrie of the Van Andel Research Institute in Michigan tells Devlin. “That’s what we plan to look at next – which factor or factors tip the scale in favor of Parkinson’s.”
The fact that removing the appendix does not give 100 percent protection from Parkinson’s means the organ is probably not the only source of the proteins. Cunningham at ScienceNews reports that previous research has found α-synuclein in other areas of the gut.
Currently, there are ongoing trials looking at how to clear α-synuclein from the brain. If those techniques work, they might also apply to the appendix and gut, helping to prevent the disease before it starts.
But the disease if very complicated, and a cure is not likely to be that simple. According to a press release, in about 10 percent of the 10 million people worldwide who have Parkinson’s, a genetic mutation seems to be the trigger for the disease.
So, does the research mean we should get voluntary appendectomies to prevent the disease? James Beck, chief scientist at the Parkinson’s Foundation, tells Susan Scutti at CNN that even if the disease might start in the gut, surgery is not the answer. There are still many questions about the process to answer.
“The question that remains is why Parkinson’s develops in only some people with abnormal alpha synuclein aggregation in the gut, and why others are seemingly resistant,” Tom Foltynie of the Institute of Neurology at University College London tells The Guardian’s Devlin. “An answer to this will help us intervene to prevent those processes linking gut pathology to brain disease.”
In the meantime, researchers are making progress on treating Parkinson’s, which affects 1 million Americans, via other methods. Last year, tests revealed that one type of drug could turn destructive proteins into protective ones and partially halt the disease.