Fecal transplants ease motor symptoms in early Parkinson’s: Study
Patients also saw improvements in constipation, quality of life
Written by |
- Fecal transplants safely eased motor symptoms and constipation in patients with early Parkinson's.
- The treatment improved quality of life and reduced levels of harmful gut bacteria.
- This therapy shows promise for Parkinson's, warranting further research.
Fecal transplant — a procedure in which stool from healthy donors is transferred into a patient’s gut to restore a more normal bacterial balance — safely eased motor symptoms and constipation in adults with early, untreated Parkinson’s disease, according to a study. These patients also reported improvements in quality of life.
These findings are based on data from a Phase 2 clinical study (ChiCTR2200064151) that evaluated the safety and effectiveness of fecal transplants in early Parkinson’s disease. The study also examined how the transplant alters the gut microbiota — the community of bacteria and other microbes living in the digestive system — finding that it reduced levels of harmful bacteria.
The study, “Gut microbiota modulation via repeated donor fecal transplantation improves motor and gastrointestinal symptoms in drug-naïve Parkinson’s disease: a randomized phase 2 trial,” was published in Signal Transduction and Targeted Therapy by a team of researchers in China.
“Together, these results … reinforce the growing body of evidence supporting gut microbiota modulation as a viable disease-modifying avenue in PD [Parkinson’s disease],” the researchers wrote.
Gut-brain axis has been linked to development of Parkinson’s
The gut-brain axis — a two-way line of communication between the digestive system and the brain — and the growth of abnormal gut microbiota have been linked to the development and progression of Parkinson’s.
Researchers have thus been exploring how modifying the gut environment could be used to treat the neurodegenerative disease. A possible approach is a fecal transplant, which the scientists further explored in their study.
The trial included 72 adults with recently diagnosed Parkinson’s who were randomly assigned to receive repeated fecal transplants of their own stool (autologous) or stool from a healthy donor. An autologous transplant wouldn’t be expected to have a therapeutic effect in the gut, so these patients served as a control group to mimic the transplant procedure.
Transplants were given in four-week cycles via a thin, flexible tube inserted into the colon, with the goal of gradually reshaping the gut microbiota. Patients received fecal transplants during the first week of each cycle, with higher doses for the first three days and lower doses for the next four. The study involved three treatment cycles, followed by monitoring up to 35 weeks, or about eight months. Of the 72 patients, 66 completed the full 35-week study.
The main goal was to track motor function using the Unified Parkinson’s Disease Rating Scale Part III, in which lower scores indicate milder motor symptoms. Patients receiving donor transplants improved by a mean of 3.8 points, compared with almost no change observed in the control group. Those in the donor transplant group were also about twice as likely to achieve a clinically meaningful improvement of at least 3.25 points (45.5% vs. 21.2%).
Measures of overall gastrointestinal symptom burden also improved
The severity of constipation, a common nonmotor symptom of Parkinson’s, also eased significantly with donor fecal transplants relative to the control group. Benefits were observed as early as 11 weeks (nearly three months) and sustained through week 35. Quality of life and measures of overall gastrointestinal symptom burden also improved.
Other measures, including those evaluating activities of daily living, nonmotor symptoms, and cognition, either showed no improvements or early improvements that were not sustained to week 35.
Analysis of gut microbiota showed that patients receiving donor fecal transplants developed a gut bacterial community more similar to that of the healthy donors. Harmful bacteria such as Escherichia and Shigella became less abundant, and these changes were linked to milder motor and gastrointestinal symptoms, “supporting a gut-brain mechanistic link,” the researchers wrote.
Biochemical tests found higher levels of dopamine — the brain signaling chemical that’s lost in Parkinson’s — in the stool of people who received donor transplants. These patients also showed a reduction in gut levels of alpha-synuclein, a protein that forms toxic clumps in Parkinson’s, and an increase in E-cadherin, a protein that helps maintain gut integrity.
Fecal transplantation was safe and well-tolerated. Side effects were mild and included abdominal discomfort, bloating, and diarrhea. No serious side effects were reported.
Overall, this study shows that changing gut bacteria through repeated donor fecal transplants may ease motor and gastrointestinal symptoms in early, untreated Parkinson’s, according to the authors.
“Future studies should validate these results in larger, multicenter cohorts … refine delivery approaches, and identify microbial biomarkers to enable precision microbiome-based interventions in PD,” the team concluded.
