Multidisciplinary and Comparative Investigations of Potential Psychobiotic Effects of Lactobacillus Strains Isolated From Newborns and Their Impact on Gut Microbiota and Ileal Transcriptome in a Healthy Murine Model

• Published in: Frontiers in cellular and infection microbiology 2019-07, Vol.9, p.269
• Main Authors: Beck, Bo Ram, Park, Gun-Seok, Jeong, Do Yeun, Lee, Yong Hyun, Im, Sunghoon, Song, Won Ho, Kang, Jihee
• Format: Article
• Language: English
• Subjects: Administration, Oral; Animals; anti-inflammation; Cellular and Infection Microbiology; Circadian Rhythm; Dopamine - blood; Feces - microbiology; Gastrointestinal Microbiome; gut microbiota; Ileum - immunology; Ileum - microbiology; Immunologic Factors - metabolism; Interleukin-10 - metabolism; Lacticaseibacillus casei - growth & development; Lacticaseibacillus casei - isolation & purification; Lactobacillus reuteri; Limosilactobacillus reuteri - growth & development; Limosilactobacillus reuteri - isolation & purification; Macrophages - immunology; Macrophages - microbiology; Mice; Mice, Inbred C57BL; Microbial Interactions; neurotransmitters; Probiotics - administration & dosage; psychobiotics; Psychotropic Drugs - administration & dosage; RAW 264.7 Cells; Serotonin - blood; Transcriptome
• ISSN: 2235-2988; 2235-2988
• DOI: 10.3389/fcimb.2019.00269

Psychobiotics are probiotic microorganisms that may exert positive influence on the psychological status of the host. Studies have revealed immunological and microbiological correlations of gut microbiota and the gut-brain axis, and have investigated psychobiotics based on the findings of the gut-brain axis. Considering their mode of actions, the present study sets anti-inflammatory effect, neurotransmitter modulation, and gut microbiota modulation as three essential criteria to evaluate ATG-F1 (F1), ATG-F3 (F3), and ATG-F4 (F4) isolated from newborns as psychobiotics candidates in a healthy mouse model and compares the results with a non-treated control group and an ampicillin-induced gut dysbiosis (Amp) group as a negative control. The F3 and F4 strains showed anti-inflammatory effects in RAW264.7 murine macrophages, and the level of anti-inflammatory cytokine interleukin (IL)-10 increased in ileums of mice orally administered with the F4 strain. Serum dopamine level significantly increased only in the F4-treated group as compared with the control group. Serum serotonin level was unaffected in -treated groups, while a significant decrease in serum serotonin level was observed in the Amp group. Bacteroidetes population increased in fecal samples of the F4-treated group as compared with the control, and S24-7 and population significantly increased at family level in fecal samples from the F4-treated group as compared with the control. In contrast, the Amp group showed an increase in the level of Proteobacteria and a decrease in the level of Bacteroidetes as compared with the control group. Transcriptome analysis revealed a distinctive clustering in ileums from the F4-treated group as compared to other experimental groups. In addition, the circadian rhythm pathway showed maximum enrichment in ileums of -treated mice, and the F4-treated group showed the highest fold changes in circadian rhythm-related genes ( , and ). Conclusively, ATG-F4 is suggested as a potential psychobiotics through demonstrations of anti-inflammatory effects, serum dopamine modulation, and gut microbiota modulation in a healthy murine model in the present study. Moreover, we carefully suggest gut circadian rhythm modulation as another important criterion of psychobiotics, which may have an important role in the gut-brain axis.