Data published in Nature’s Scientific Reports indicated that the strain did not shift the whole gut microbiota, but it did boost the abundance of Lactobacillus species, while stimulatory effects were also observed on the immune system.
“Taken together, administration of the probiotic L. fermentum strain JDFM216 in aged mice confirmed its features of the health promotion on the cognitive host responses and the immune system through the alteration of the intestinal taxonomic composition,” wrote scientists from Jeonbuk National University, Seoul National University, the Microbial Institute for Fermentation Industry (Jeonbuk), Chungnam National University, Jeju National University, and Jeonju University.
“The findings facilitate our understanding on the efficacy of probiotics and probiotic-derived factors on the regulation of the host psychological and immune health, thus providing a fascinating potential for probiotic application in human disease prevention and treatment.”
The study adds to the ever-growing area of research around the gut-brain axis, that bi-directional interaction between the gastrointestinal tract and the nervous system. The area is gaining increasing attention from scientists and consumers.
A 2015 review in Neuropsychiatric Disease and Treatment by Linghong Zhou and Jane Foster from McMaster University in Canada noted that the bacteria present in the gut affects the communication between belly and brain, and the lack of healthy gut microbiota lead to dysfunction in the gut–brain axis, which in turn may lead to neuropsychological, metabolic, and gastrointestinal disorders.
However, the vast majority of the research in this area has been in animals, therefore extrapolating these data to more complex humans remains a significant challenge.
The Korean study assessed performance in a battery of tests, including Y-maze tests, wheel running tests, accelerated rotarod tests, balance beam tests, and forced swimming tests, in adult mice who were supplemented with L. fermentum JDFM216 or a ‘placebo’ for 50 weeks.
The results showed that the probiotic-fed mice performed better on Y-maze, accelerated rotarod, beam-walking and forced swimming tests than the placebo mice, indicating “a significant positive modulation of cognitive behaviors and physiological properties in aged mice”, said the researchers.
Regarding impacts on the immune system, the probiotic-fed mice were found to have enhanced phagocytic activity of macrophages and enhance intestinal sIgA.
Microbiome comparison with young mice revealed that the placebo-fed aged mice had lower levels of species in the Porphyromonadaceae family and the Lactobacillus genus. However, aged mice consuming L. fermentum JDFM216 had significant increases in the abundance of Lactobacillus species.
“In this study, we observed that JDFM216 treatment significantly and mostly increased one OTU [operational taxonomic unit] belonging to the genus Lactobacillus, the abundance of which was correlated to vitamin metabolism and other beneficial substances such as butanoate, lipoic acid, and taurine,” reported the researchers.
The researchers added: “In order to better understand the molecular mechanisms of JDFM216 that link the gut microbiota, immune, and central nervous systems in a network communication, further investigation on a broader range of immune responses will be conducted.”
Source: Scientific Reports
10, 21701 (2020). https://doi.org/10.1038/s41598-020-77587-w
“Probiotic Lactobacillus fermentum strain JDFM216 improves cognitive behavior and modulates immune response with gut microbiota”
Authors: M.R. Park, et al.