Appendix removal may lower chances of getting Parkinson's disease, study suggests

Removing the appendix could reduce the risk of Parkinson’s disease in later life by as much as 20 per cent, according to new research.

Thought to be linked to abnormal clumps of protein molecules which kill nerve cells, Parkinson’s causes gradually worsening tremors in the limbs and muscles.

Previous research has suggested the disease starts in the gut. But now a team of American and Swedish researchers have discovered the appendix acts as a reservoir for these abnormal “alpha-synuclein” proteins, even in adults without the disease

The team analysed the health records of 1.6 million Swedish adults and found that those who had an appendectomy had a 19.3 per cent reduction in their chance of developing the disease.

A second analysis of 849 patients diagnosed with Parkinson’s, found that having an appendectomy was associated with a delay in the onset of the disease by 3.6 years on average.

However, an appendectomy had no effect on Parkinson’s development among people who had a family history or genetic risk of the disease.

“Our results point to the appendix as a site of origin for Parkinson’s and provide a path forward for devising new treatment strategies that leverage the gastrointestinal tract’s role in the development of the disease,” said Dr Viviane Labrie one of the authors of the study published in the Science Translational Medicine journal.

Despite having a reputation for being useless the appendix has a poorly understood role in the immune system and Dr Labrie said it was “surprising” that the disease causing protein clumps were evident in the appendix of both healthy adults and people with the disease.

“It appears that these aggregates – although toxic when in the brain - are quite normal when in the appendix,” added the researcher from the at Van Andel Research Institute, US.

Professor Tom Foltynie, from the University College London Institute of Neurology, was not involved with the study but said: “This is strong, highly valuable, long term epidemiological evidence” supporting a link between Parkinson’s and the gut. 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.”

The findings emerged as a new therapy with the potential to stop the progression of Parkinson's was developed by scientists at Australia's University of Queensland.

A small molecule known as MCC950 worked to effectively cool the brain of a disease sufferer in a number of animal models, preventing the loss of brain cells, researchers said. They hope human clinical trials can begin in 2020.

Associate Professor Trent Woodruff said: "The disease is characterised by the loss of brain cells that produce dopamine, which is a chemical that co-ordinates motor control, and is accompanied by chronic inflammation in the brain.We found a key immune system target, called the NLRP3 inflammasome, lights up in Parkinson's patients, with signals found in the brain and even in the blood.

"MCC950, given orally once a day, blocked NLRP3 activation in the brain and prevented the loss of brain cells, resulting in markedly improved motor function."

The study, which was also published in Science Translational Medicine, was supported by The Michael J Fox Foundation for Parkinson's Research and Shake it Up Australia Foundation.

Parkinson’s UK says the lifetime risk of developing the disease is around 2.7 per cent and 145,519 people currently have disease in the UK.

Claire Bale, head of research at the charity said: ”There is much still to learn about how surgical approaches, such as removing the appendix, may stop the progression of toxic proteins that cause Parkinson’s. However, these approaches are unlikely to eliminate the condition, as Parkinson’s may also start in other areas of the body or brain.”