Research led by Vancouver Coastal Health Research Institute scientist Dr Silke Appel-Cresswell is the first to examine whether a multistrain probiotic could help relieve anxiety symptoms in people with Parkinson disease. Parkinson disease often causes muscle rigidity linked to reduced dopamine levels, along with tremors or slowed movements. Dopamine replacement therapy can help relieve symptoms of anxiety and stiffness among some patients, but existing treatments take a while to kick in, and often wear off within a few hours.

For her randomized, triple-blind and placebo-controlled clinical trial, “Treating Anxiety in Parkinson’s Disease with a Multi-Strain Probiotic (TAP),” Appel-Cresswell is recruiting adults with Parkinson disease ages 40 to 80 to investigate the effectiveness of the Ecologic BARRIER849 probiotic as an anxiety reduction treatment. The over-the-counter probiotic—not currently available in Canadian stores—contains a mixture of live bacterial cultures targeted at promoting a healthy gut flora, which the research team believes may set off a chain reaction that stops the anxiety cycle.

New treatment would target the microbiome of Parkinson disease patients

The guts of Parkinson patients often face a variety of challenges, says Appel-Cresswell. Constipation is a very early and very widespread symptom. Their gut’s microbiome is also more likely to drive inflammation. This inflammation causes damage to the gut barrier—composed of mucosal membrane and other protective cells—allowing bacteria and toxins to escape, Appel-Cresswell explains.

Leaked toxins may contribute to elevated levels of damaging microbial metabolites in Parkinson disease patients, which Appel-Cresswell identified in her prior research. These toxins have also been found in higher concentrations in patients’ cerebral-spinal fluid, says Appel-Cresswell.

Bacterial strains contained within the Ecologic BARRIER probiotic have been found to improve gut barrier function and mood, possibly due to its rebalancing of gut flora and promotion of healthy gut bacteria, says Appel-Cresswell.

To test whether or not this is true for Parkinson disease patients, participants in Appel-Cresswell’s study will complete a variety of motor function, cognition, and neuropsychiatric tests before and after a 12-week trial of one sachet twice daily probiotic or placebo powder. Results will be evaluated for changes in participants’ anxiety levels, motor function, levels of fatigue, depression, and microbiome composition.

To learn more about the TAP study, contact coordinator Petra Uzelman at 604 827-0576 or petra.uzelman@ubc.ca.