Parkinson’s disease: At a glance
Parkinson’s disease (PD) is a chronic neurological disease that currently affects about 1 million Americans and is the second most common neurodegenerative disease in the world. Patients with PD experience a wide range of symptoms that get progressively worse, including muscle rigidity, tremor, difficulty with walking and balance and changes in cognitive function and behavior. Hereditary factors, environmental toxins and traumatic head injuries are a few of the known risk factors that can lead to a PD diagnosis.
PD-GI connection
Patients with PD also have non-motor challenges involving their gastrointestinal tract, including constipation, weight loss, dysphagia, sialorrhea, gastric dysmotility and constipation. These symptoms often negatively impact daily quality of life. Many studies have shown that GI symptoms are present in at least 50% of patients with PD. Constipation, specifically, affects approximately 80% to 90% of PD patients, and can show up as early as 10 years before a PD diagnosis.
Dr. Hall and her team’s focus on the PD gut-brain connection is reflective of the larger, national trend to study this vital, informative connection. Their research also builds off work done by former RUSH colleague Kathleen M. Shannon, MD, FAAN, FANA, the current chair of the Department of Neurology at the University of Wisconsin, Madison.
In her work, Dr. Shannon showed the prevalence of alpha-synuclein (α-Syn), a neuronal protein most abundantly found in the brain that helps regulate synaptic vesicle trafficking, in the GI tract of most PD patients. This indicated that proinflammatory dysbiosis, or gut imbalance, in PD patients could cause the misfolding of α-Syn in the brain and thus, the development of PD pathology.
Researchers and clinicians are unsure whether a patient’s microbiome in the GI tract is an environmental cause of PD, a catalyst that can speed up disease progression or a symptom of PD progression.
“It’s possible that environmental toxins get through the bowel wall, what we call a ‘leaky gut,’” says Dr. Hall, a neurologist and movement disorders specialist and the division chief of the Section of Movement Disorders at RUSH University Medical Center. “This can cause the disease to progress faster or become more severe.”
The bar and its impact
Dr. Hall and Dr. Keshavarzian, a gastroenterologist and the director of the RUSH Center for Integrated Microbiome and Chronobiology Research, wanted to understand how a patient’s diet and microbiome state would affect PD symptoms.
They tested a proprietary prebiotic food bar that was developed by Dr. Keshavarzian with a group of 20 patients, who were either newly diagnosed and non-medicated or who had more advanced disease and were currently receiving treatment. By reintroducing beneficial prebiotic bacteria, which contain small chain fatty acids, the intestinal mucosa reverted to this normal, healthy state.
“One patient who had been constipated prior to the trial reported his constipation had resolved,” Dr. Hall explains. “This formula enabled us to improve the patient’s symptoms, which is definitely a positive outcome.”
The RUSH PD-GI Clinic
The work done by Dr. Hall and Dr. Keshavarzian fits within the overall scope of the RUSH Parkinson’s Disease Gastrointestinal Clinic, a novel multidisciplinary clinic focused on the gastrointestinal health of patients with PD and other movement disorders. This unique collaboration of experts in several specialties, including neurology, gastroenterology, psychology and behavioral sciences, nutrition, and physical therapy was the first of its kind in the United States.
Next steps
Dr. Hall’s goal for the next phase of the research would be threefold: 1) to look at the impact of the prebiotics with a larger test group; 2) to give the bar over a longer period of time; and 3) to study the efficacy of the bar by monitoring the patients’ motor outcomes.
“We’re excited about the potential of this formula to help patients at least have some symptom relief,” Dr. Hall says. “It’s not a medicine It’s not a surgical intervention. It’s easy.”
