People with Parkinson’s know that having an untreatable condition can be devastating. There are drugs and methods of treatment, but as of yet, there is no cure. The disease, which affects the nervous system, is a life-long degenerative disorder that affects the quality of life of everyone who has it.
It’s always been believed that the root cause of the disease lay in the brain since the symptoms of the disease are largely caused by an imbalance of dopamine. But new research has shown that the disease might begin in the gut. Paving a new way, this research that shows the link between the stomach and the brain could lead to new treatment methods and much earlier diagnosis. Understanding this relationship could have profound effects for many, and the research aims to eventually change the lives of those living with Parkinson’s.
Exactly what causes Parkinson’s disease is unknown, however, there is a strong evidence that it is caused by
- toxins (manganese, carbon monoxide, carbon disulfide)
- oxidative stress
One of the main symptoms of Parkinson’s is slowed movement. Affected people might walk very hesitantly and only take short increasingly small steps. Initiating that first step is particularly hard, and once they are moving it’s difficult to stop again. As the condition progresses, the arms stop swinging when they walk and gripping their hands for tasks becomes more difficult. As well, due to reduced activity in the facial muscles, the face becomes more mask-like and speech becomes more monotone (1).
People with Parkinson’s experience muscle stiffness especially in the arms, legs, and neck. Even when someone else tries to force their arms or legs to move, the muscles put up resistance. This can even cause extreme aches in the muscles (1).
This symptom of Parkinson’s is fairly well known, and most people with Parkinson’s will have a tremor. The shaking associated with tremors will not be as severe during movement but is particularly common in the hands. Things like handwriting become more difficult the worse these tremors become (1).
Link between the stomach and Parkinson’s
In a recent study on mice, it was demonstrated that there might be a link between Parkinson’s disease and the stomach. These new findings might explain why people with Parkinson’s complain of stomach problems, like constipation, for up to ten years before their diagnosis (3).
The team of researchers found out about the link between the gut microbiome and Parkinson’s disease through observing the spread of toxic fibers made of a substance known as alpha-synuclein. For some reason in people with Parkinson’s these alpha-synuclein clump together and form fibers that damage the nerves in the brain. It was found that those with Parkinson’s also had these fibers in the gut (3).
Parkinson’s and the microbiome
In the study, mice with Parkinson’s were raised in normal non-sterile cages, or in sterile germ-free environments. The mice who were raised in the sterile environment showed fewer motor deficits and less toxic fibers in the brain. The mice raised in the normal environment developed Parkinson’s as expected, but when treated with antibiotics their symptoms were reduced, suggesting something in their microbiome was enhancing symptoms (3).
The team injected the mice raised in the sterile environment with gut bacteria from humans with Parkinson’s and they quickly deteriorated. In comparison with when gut bacteria was injected from healthy people, it did not have the same effect. This left the team of researchers quite confident that gut bacteria regulate, or are even required for the symptoms of Parkinson’s disease (3).
They believe that the gut bacteria might be releasing chemicals that over activate parts of the brain leading to damage and the onset of the disease. But they agree a lot more research needs to be done before they can conclusively say what’s going on (3).
The team of researchers now want to look at the gut microbiomes of people with Parkinson’s to try and narrow down which microbes seem to be predisposing people to the disease. This could mean a potential screening process for Parkinson’s and would help diagnose before symptoms demonstrate. It could also contribute to generating new treatment options (3). It will take many years to translate these findings in mice into human trials, but we are well on the way to understanding this elusive disease much better.