Basic Study
Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Apr 21, 2017; 23(15): 2696-2704
Published online Apr 21, 2017. doi: 10.3748/wjg.v23.i15.2696
Effect of Lactobacillus rhamnosus HN001 and Bifidobacterium longum BB536 on the healthy gut microbiota composition at phyla and species level: A preliminary study
Marco Toscano, Roberta De Grandi, Laura Stronati, Elena De Vecchi, Lorenzo Drago
Marco Toscano, Roberta De Grandi, Lorenzo Drago, Laboratory of Clinical Microbiology, Department of Biomedical Science for Health, University of Milan, 20133 Milan, Italy
Laura Stronati, Department of Cellular Biotechnology and Hematology, 00161 Roma, Italy
Elena De Vecchi, Lorenzo Drago, Laboratory of Clinical Chemistry and Microbiology, IRCCS Galeazzi Orthopaedic Institute, University of Milan, 20164 Milan, Italy
Author contributions: Drago L led the conception of manuscript and contributed to draft it; Toscano M and De Grandi R performed experiments, analyzed data and prepared the manuscript; Stronati L and De Vecchi E contributed to the acquisition of samples, analysis and interpretation of data.
Institutional review board statement: This study was reviewed and approved by the Scientific Direction of IRCCS Galeazzi Orthopaedic Institute in the Current Research 2015.
Informed consent statement: All subjects enrolled in the study were volunteers who were informed in detail about the aim of the study and they gave informed consent to the study. As declared in “Materials and Methods”, indeed, all individuals personally delivered fecal samples to the Laboratory of Clinical Microbiology were samples were analyzed.
Conflict-of-interest statement: The authors declare no conflicts of interests related to the publication of this study.
Data sharing statement: No additional data was available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Lorenzo Drago, PhD, Professor of Microbiology and Clinical Microbiology, IRCCS Galeazzi Orthopaedic Institute, Via Galeazzi 4, 20164 Milan, Italy. lorenzo.drago@unimi.it
Telephone: +39-02-66214839 Fax: +39-02-66144774
Received: December 19, 2016
Peer-review started: December 23, 2016
First decision: January 10, 2017
Revised: January 27, 2017
Accepted: March 20, 2017
Article in press: March 20, 2017
Published online: April 21, 2017
Processing time: 121 Days and 22.8 Hours
Abstract
AIM

To evaluate the ability of Lactobacillus rhamnosus HN001 and Bifidobacterium longum BB536 to colonize the intestinal environment of healthy subjects and modify the gut microbiota composition.

METHODS

Twenty healthy Italian volunteers, eight males and twelve females, participated in the study. Ten subjects took a sachet containing 4 × 109 colony-forming units (CFU) of Bifidobacterium longum BB536 and 109 CFU of Lactobacillus rhamnosus HN001, 30 min before breakfast (pre-prandial administration), while ten subjects took a sachet of probiotic product 30 min after breakfast (post-prandial administration). The ability of Lactobacillus rhamnosus HN001 and Bifidobacterium longum BB536 to colonize human gut microbiota was assessed by means of quantitative real-time PCR, while changes in gut microbiota composition were detected by using Ion Torrent Personal Genome Machine.

RESULTS

Immediately after 1-mo of probiotic administration, B. longum BB536 and L. rhamnosus HN001 load was increased in the majority of subjects in both pre-prandial and post-prandial groups. This increase was found also 1 mo after the end of probiotic oral intake in both groups, if compared to samples collected before probiotic consumption. At phyla level a significant decrease in Firmicutes abundance was detected immediately after 1-mo of B. longum BB536 and L. rhamnosus HN001 oral intake. This reduction persisted up to 1 mo after the end of probiotic oral intake together with a significant decrease of Proteobacteria abundance if compared to samples collected before probiotic administration. Whereas, at species level, a higher abundance of Blautia producta, Blautia wexlerae and Haemophilus ducrey was observed, together with a reduction of Holdemania filiformis, Escherichia vulneris, Gemmiger formicilis and Streptococcus sinensis abundance. In addition, during follow-up period we observed a further reduction in Escherichia vulneris and Gemmiger formicilis, together with a decrease in Roseburia faecis and Ruminococcus gnavus abundance. Conversely, the abundance of Akkermansia muciniphila was increased if compared to samples collected at the beginning of the experimental time course

CONCLUSION

B. longum BB536 and L. rhamnosus HN001 showed the ability to modulate the gut microbiota composition, leading to a significant reduction of potentially harmful bacteria and an increase of beneficial ones. Further studies are needed to better understand the specific mechanisms involved in gut microbiota modulation.

Keywords: Probiotics; Gut microbiota; Bifidobacterium; Lactobacillus; Human health

Core tip: Several studies have described the potentially beneficial effects of many probiotic microorganisms belonging to Lactobacillus and Bifidobacterium genera. We evaluated the ability of Bifidobacterium longum BB536 and Lactobacillus rhamnosus HN001, two probiotic strains used in combination, to colonize the intestinal environment of healthy subjects and modify the gut microbiota composition. We did not observe a negative impact of probiotic on the general health status of the hosts. Contrariwise, the two bacterial strains seemed able to exert a beneficial effect on the bacterial ecology of the gastrointestinal tract, as many significant positive changes in gut microbiota composition have been highlighted.