Scientific literature linking depression and the gut microbiome is still in its infancy, mainly lacking the number of human clinical trials, she told NutraIngredients-USA at the Probiota Americas 2018 conference in Miami earlier this month.
But considering the side effects and stigma associated with anti-depressant drugs, Wallace argued that exploring the potential of probiotics as a novel therapeutic can open up new avenues for patients who want more of a nutritional and holistic approach to treatment.
Wallace is a research assistant at the Providence Care Hospital in Ontario, Canada, and a PhD candidate for neuroscience at Queen’s University.
At the conference, she presented results from a pilot study of which she was a co-author, suggesting that the probiotic strains Lactobacillus helveticus Rosell-52 and Bifidobacterium longum Rosell-175 found in Lallemand’s Probio’ Sticks, may improve depression symptoms in humans.
The ingredient combination has an approved ‘gut-brain axis’ health claim from Health Canada.
With the approved health claim, products using Lallemand’s formulation may market products with claims like “Helps to moderate general feelings of anxiety,” “promotes a healthy mood balance,” and “helps to reduce stress-related gastrointestinal complication such as abdominal pain,” among other things.
Proposed mechanism of probiotic modulation
“One of our proposed theories is that probiotics are improving the integrity of the gastrointestinal lining,” she explained.
That improvement reduces the ability of bacteria and endotoxins like lipopolysaccharide to leak into the bloodstream, which Wallace said causes an elevated immune response which leads to inflammation, which then may lead to depression symptoms.
“Underlying mechanisms is definitely one area that needs further research,” she said. “We need to be looking at this at a neurophysiological level, but again, one of the most important things is that we have more randomized controlled-trials in samples of clinically depressed patients.