At Bowel & Cancer Research we have recognised the long held theory that Parkinson's disease starts in the gut rather than in the brain, and a new study provides more evidence to support this line of thought.

Parkinson's disease is caused by disruption in the nerve cells within the brain. It is a degenerative condition, the main symptoms of which are shaking (tremors), slowness of movement and stiffness. There is no cure currently for Parkinson's disease but treatments can improve symptoms and the quality of life of the patient.

Parkinson's comes about at the result of damage to proteins found on nerve cells in the brain, called alpha-synucleins. In Parkinson's disease these proteins become malformed and clump together. This affects the production of dopamine, a neurotransmitter, which helps the cells to signal to each other.

This newest study in mice has shown that the problem with alpha-synuclein starts within the gut and then travels up the vagus nerve into the brain. The vagus nerve is major communications highway within the human body delivering a two way connection between the gut and the brain that involves the central nervous system (CNS) and enteric nervous system (ENS) found in the gut. In fact, the vast majority of communication (some 90%) goes from the gut to the brain rather than the other way round.

For many years, the gut was considered to have a reasonably limited function related to the digestion of our food. What is becoming increasingly clear is the vital role the gut and the ENS has to play in our overall health and well being. The gut contains more neurons, for example, than the spinal cord or the peripheral nervous system (the system that connects the central nervous system to the rest of the body). This new finding on the driver to Parkinson's disease underscores this critical role.

This research raises the enticing prospect that ways may be found in future to prevent the development of Parkinson's disease in the brain by preventing the movement of the damaged alpha-synucleins from the gut to the brain.

The study was co-led by Professor Ted Dawson from Johns Hopkins University school of Medicine and published in the journal Neuron.