The Guardian1 ran a story yesterday, pulling together some of the latest evidence linking the origins of Parkinson’s disease to the gut. It has long been thought that when a protein called alpha-synuclein is misfolded and clumps together in the brain, it is associated with nerve damage and a reduction in dopamine. This, in turn, is presumed to be responsible for the deterioration in the control of speech and movement, two of the key symptoms of Parkinson’s disease. But recent research in this field has been looking at the gut as a potential point of origin for the misfolded alpha-synuclein.
The direct two-way channel between the gut and brain (the gut-brain axis) is being seen as an increasingly important mediator of human health. A recent study with mice has added weight to the hypothesis that the misfolded alpha-synuclein originates in the intestinal tract and use the vagus nerve to travel to the brain. This follows earlier findings that indicate having your appendix removed reduces the chances of developing Parkinson’s in later life. Taken together these studies signpost the possibility that prevention of Parkinson’s disease could focus on the gut rather than the brain.
However, there are a number of further steps that need to be made, not least a convincing explanation of what causes the misfolding of alpha-synuclein in the gut. As such, it is premature to conclude that the primary cause of Parkinson’s disease originates in the digestive tract. But this latest evidence underpins the importance of the gut in human health more generally. Understanding how to maintain a healthy gut microbiome through the use of prebiotics and probiotics is entering the mainstream. In addition, science is also drawing our attention to the pressing need to avoid substances that degrade or limit gut health, such as the chemicals that are present in a wide range of foodstuffs.