- Alteration in the gut bacterial communities can be an indicator for Parkinson's disease
- Certain gut microbes are associated with non-motor Parkinson's symptoms like depression
- People with Idiopathic Rapid-Eye-Movement Sleep Behaviour Disorder (iRBD) are at an elevated risk of developing Parkinson's disease later in life
Parkinson's disease is a dangerous illness. By the time motor activities dysfunction like the tremors or muscle rigidity, few portions of the brain would have already become irreversibly destroyed. However, by this stage, the disease would have already begun decades earlier.
The study was lead by Prof. Paul Wilmes, head of the Eco-Systems Biology Group at the Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg.
In search of an early portent of the disease, the research team has already found one in the gut. The team showed that the bacterial community in the gut of patients with Parkinson's differs from that of healthy people, even when they are at an early stage of the disease.
According to the "dual hit" hypothesis, an unknown pathogen invades into the body through the nose or the gastrointestinal tract, which are the two possible ports of entry.
Once inside, it sets a pathological process in motion, and above all the misfolding of the protein, alpha-synuclein takes place.
Alpha-synuclein is a protein, and the exact function remains unknown and is presumed to be involved in the excretion of messengers like dopamine.
The misfolding of this protein happens through the nerve pathways, where even after decades it can produce the typical clumping in the dopaminergic cells, which are known as Lewy bodies and have the exact characteristics of Parkinson's disease. Finally, nerve cells start to die off, and the typical symptoms of Parkinson's appear.
iRBD Patients at Risk of Developing Parkinson's disease
The research team was led by Wilmes, together with Prof. Brit Mollenhauer and Prof. Wolfgang Oertel, who are physicians and their teams in Göttingen, Kassel, and Marburg.
The question of whether the early events during the disease change the bacterial community, the microbiome at the two possible ports of entry is something that the research team explored.
About 76 patients who have Parkinson's and 78 healthy people from the control group were included in the long-term study. The samples were taken from the nose and gut and examined the microbiome of 21 patients who were diagnosed with Idiopathic Rapid-Eye-Movement Sleep Behaviour Disorder (iRBD).
People with this sleep disorder were found to be at an elevated risk of developing Parkinson's disease later in life. The bacterial community of the gut of all the participants differed considerably between all three groups.
Dr. Anna Heintz-Buschart from the Eco-Systems Biology Group said that patients who had Parkinson's could be differentiated easily from the healthy controls based on their gut bacteria. But, the majority of these differential bacteria displayed similar trends in the iRBD group.
For example, certain germs were more common in one group than the other, while in others, the count was found to be lower. In the samples, no such differences were seen in the nasal cavities of the participants.
The results showed that certain gut microbes were found to be associated with non-motor Parkinson's symptoms, like depression.
Paul Wilmes explained, "We hope that, by comparing the groups, we will learn to better understand the role of the microbiome in the process of the disease and to find out what changes occur and when they occur."
"This might deliver new starting points for early treatment of the disease. It would also be essential knowledge for one day being able to use the absence or presence of certain bacteria as a biomarker for early detection of the disease." The findings of this study could lead to new starting points for early treatment of the disease. The information gained from this study could be helpful in the future whether in the presence or absence of certain bacteria as a biomarker for early detection of the disease.
Apart from the LCSB research team, other scientists from the Departments of Neurology and Neuropathology of the University Medical Center Göttingen and Paracelsus-Elena-Klinik in Kassel, the Department of Neurology of Philipps Universität in Marburg were involved in the study.
Luxembourg Rotary Club under its "Espoir en tête" program supported this study through the Luxembourg National Research Fund (FNR) and the German Research Foundation (DFG).
- Anna Heintz-Buschart, Urvashi Pandey, Tamara Wicke, Friederike Sixel-Döring, Annette Janzen, Elisabeth Sittig-Wiegand, Claudia Trenkwalder, Wolfgang H. Oertel, Brit Mollenhauer, Paul Wilmes. The nasal and gut microbiome in Parkinson's disease and idiopathic rapid eye movement sleep behavior disorder. Movement Disorders(2017).