Hypoxia and inactivity related physiological changes precede or take place in absence of significant rearrangements in bacterial community structure: The PlanHab randomized trial pilot study.

We explored the assembly of intestinal microbiota in healthy male participants during the randomized crossover design of run-in (5 day) and experimental phases (21-day normoxic bed rest (NBR), hypoxic bed rest (HBR) and hypoxic ambulation (HAmb) in a strictly controlled laboratory environment, with...

Full description

Bibliographic Details
Main Authors: Robert Šket, Nicole Treichel, Susanne Kublik, Tadej Debevec, Ola Eiken, Igor Mekjavić, Michael Schloter, Marius Vital, Jenna Chandler, James M Tiedje, Boštjan Murovec, Zala Prevoršek, Matevž Likar, Blaž Stres
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2017-01-01
Series:PLoS ONE
Online Access:http://europepmc.org/articles/PMC5718606?pdf=render
_version_ 1818279330657075200
author Robert Šket
Nicole Treichel
Susanne Kublik
Tadej Debevec
Ola Eiken
Igor Mekjavić
Michael Schloter
Marius Vital
Jenna Chandler
James M Tiedje
Boštjan Murovec
Zala Prevoršek
Matevž Likar
Blaž Stres
author_facet Robert Šket
Nicole Treichel
Susanne Kublik
Tadej Debevec
Ola Eiken
Igor Mekjavić
Michael Schloter
Marius Vital
Jenna Chandler
James M Tiedje
Boštjan Murovec
Zala Prevoršek
Matevž Likar
Blaž Stres
author_sort Robert Šket
collection DOAJ
description We explored the assembly of intestinal microbiota in healthy male participants during the randomized crossover design of run-in (5 day) and experimental phases (21-day normoxic bed rest (NBR), hypoxic bed rest (HBR) and hypoxic ambulation (HAmb) in a strictly controlled laboratory environment, with balanced fluid and dietary intakes, controlled circadian rhythm, microbial ambiental burden and 24/7 medical surveillance. The fraction of inspired O2 (FiO2) and partial pressure of inspired O2 (PiO2) were 0.209 and 133.1 ± 0.3 mmHg for NBR and 0.141 ± 0.004 and 90.0 ± 0.4 mmHg for both hypoxic variants (HBR and HAmb; ~4000 m simulated altitude), respectively. A number of parameters linked to intestinal environment such as defecation frequency, intestinal electrical conductivity (IEC), sterol and polyphenol content and diversity, indole, aromaticity and spectral characteristics of dissolved organic matter (DOM) were measured (64 variables). The structure and diversity of bacterial microbial community was assessed using 16S rRNA amplicon sequencing. Inactivity negatively affected frequency of defecation and in combination with hypoxia increased IEC (p < 0.05). In contrast, sterol and polyphenol diversity and content, various characteristics of DOM and aromatic compounds, the structure and diversity of bacterial microbial community were not significantly affected over time. A new in-house PlanHab database was established to integrate all measured variables on host physiology, diet, experiment, immune and metabolic markers (n = 231). The observed progressive decrease in defecation frequency and concomitant increase in IEC suggested that the transition from healthy physiological state towards the developed symptoms of low magnitude obesity-related syndromes was dose dependent on the extent of time spent in inactivity and preceded or took place in absence of significant rearrangements in bacterial microbial community. Species B. thetaiotamicron, B. fragilis, B. dorei and other Bacteroides with reported relevance for dysbiotic medical conditions were significantly enriched in HBR, characterized with most severe inflammation symptoms, indicating a shift towards host mucin degradation and proinflammatory immune crosstalk.
first_indexed 2024-12-12T23:31:37Z
format Article
id doaj.art-722c497dccd94c9dbf667706254820c6
institution Directory Open Access Journal
issn 1932-6203
language English
last_indexed 2024-12-12T23:31:37Z
publishDate 2017-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj.art-722c497dccd94c9dbf667706254820c62022-12-22T00:07:45ZengPublic Library of Science (PLoS)PLoS ONE1932-62032017-01-011212e018855610.1371/journal.pone.0188556Hypoxia and inactivity related physiological changes precede or take place in absence of significant rearrangements in bacterial community structure: The PlanHab randomized trial pilot study.Robert ŠketNicole TreichelSusanne KublikTadej DebevecOla EikenIgor MekjavićMichael SchloterMarius VitalJenna ChandlerJames M TiedjeBoštjan MurovecZala PrevoršekMatevž LikarBlaž StresWe explored the assembly of intestinal microbiota in healthy male participants during the randomized crossover design of run-in (5 day) and experimental phases (21-day normoxic bed rest (NBR), hypoxic bed rest (HBR) and hypoxic ambulation (HAmb) in a strictly controlled laboratory environment, with balanced fluid and dietary intakes, controlled circadian rhythm, microbial ambiental burden and 24/7 medical surveillance. The fraction of inspired O2 (FiO2) and partial pressure of inspired O2 (PiO2) were 0.209 and 133.1 ± 0.3 mmHg for NBR and 0.141 ± 0.004 and 90.0 ± 0.4 mmHg for both hypoxic variants (HBR and HAmb; ~4000 m simulated altitude), respectively. A number of parameters linked to intestinal environment such as defecation frequency, intestinal electrical conductivity (IEC), sterol and polyphenol content and diversity, indole, aromaticity and spectral characteristics of dissolved organic matter (DOM) were measured (64 variables). The structure and diversity of bacterial microbial community was assessed using 16S rRNA amplicon sequencing. Inactivity negatively affected frequency of defecation and in combination with hypoxia increased IEC (p < 0.05). In contrast, sterol and polyphenol diversity and content, various characteristics of DOM and aromatic compounds, the structure and diversity of bacterial microbial community were not significantly affected over time. A new in-house PlanHab database was established to integrate all measured variables on host physiology, diet, experiment, immune and metabolic markers (n = 231). The observed progressive decrease in defecation frequency and concomitant increase in IEC suggested that the transition from healthy physiological state towards the developed symptoms of low magnitude obesity-related syndromes was dose dependent on the extent of time spent in inactivity and preceded or took place in absence of significant rearrangements in bacterial microbial community. Species B. thetaiotamicron, B. fragilis, B. dorei and other Bacteroides with reported relevance for dysbiotic medical conditions were significantly enriched in HBR, characterized with most severe inflammation symptoms, indicating a shift towards host mucin degradation and proinflammatory immune crosstalk.http://europepmc.org/articles/PMC5718606?pdf=render
spellingShingle Robert Šket
Nicole Treichel
Susanne Kublik
Tadej Debevec
Ola Eiken
Igor Mekjavić
Michael Schloter
Marius Vital
Jenna Chandler
James M Tiedje
Boštjan Murovec
Zala Prevoršek
Matevž Likar
Blaž Stres
Hypoxia and inactivity related physiological changes precede or take place in absence of significant rearrangements in bacterial community structure: The PlanHab randomized trial pilot study.
PLoS ONE
title Hypoxia and inactivity related physiological changes precede or take place in absence of significant rearrangements in bacterial community structure: The PlanHab randomized trial pilot study.
title_full Hypoxia and inactivity related physiological changes precede or take place in absence of significant rearrangements in bacterial community structure: The PlanHab randomized trial pilot study.
title_fullStr Hypoxia and inactivity related physiological changes precede or take place in absence of significant rearrangements in bacterial community structure: The PlanHab randomized trial pilot study.
title_full_unstemmed Hypoxia and inactivity related physiological changes precede or take place in absence of significant rearrangements in bacterial community structure: The PlanHab randomized trial pilot study.
title_short Hypoxia and inactivity related physiological changes precede or take place in absence of significant rearrangements in bacterial community structure: The PlanHab randomized trial pilot study.
title_sort hypoxia and inactivity related physiological changes precede or take place in absence of significant rearrangements in bacterial community structure the planhab randomized trial pilot study
url http://europepmc.org/articles/PMC5718606?pdf=render
work_keys_str_mv AT robertsket hypoxiaandinactivityrelatedphysiologicalchangesprecedeortakeplaceinabsenceofsignificantrearrangementsinbacterialcommunitystructuretheplanhabrandomizedtrialpilotstudy
AT nicoletreichel hypoxiaandinactivityrelatedphysiologicalchangesprecedeortakeplaceinabsenceofsignificantrearrangementsinbacterialcommunitystructuretheplanhabrandomizedtrialpilotstudy
AT susannekublik hypoxiaandinactivityrelatedphysiologicalchangesprecedeortakeplaceinabsenceofsignificantrearrangementsinbacterialcommunitystructuretheplanhabrandomizedtrialpilotstudy
AT tadejdebevec hypoxiaandinactivityrelatedphysiologicalchangesprecedeortakeplaceinabsenceofsignificantrearrangementsinbacterialcommunitystructuretheplanhabrandomizedtrialpilotstudy
AT olaeiken hypoxiaandinactivityrelatedphysiologicalchangesprecedeortakeplaceinabsenceofsignificantrearrangementsinbacterialcommunitystructuretheplanhabrandomizedtrialpilotstudy
AT igormekjavic hypoxiaandinactivityrelatedphysiologicalchangesprecedeortakeplaceinabsenceofsignificantrearrangementsinbacterialcommunitystructuretheplanhabrandomizedtrialpilotstudy
AT michaelschloter hypoxiaandinactivityrelatedphysiologicalchangesprecedeortakeplaceinabsenceofsignificantrearrangementsinbacterialcommunitystructuretheplanhabrandomizedtrialpilotstudy
AT mariusvital hypoxiaandinactivityrelatedphysiologicalchangesprecedeortakeplaceinabsenceofsignificantrearrangementsinbacterialcommunitystructuretheplanhabrandomizedtrialpilotstudy
AT jennachandler hypoxiaandinactivityrelatedphysiologicalchangesprecedeortakeplaceinabsenceofsignificantrearrangementsinbacterialcommunitystructuretheplanhabrandomizedtrialpilotstudy
AT jamesmtiedje hypoxiaandinactivityrelatedphysiologicalchangesprecedeortakeplaceinabsenceofsignificantrearrangementsinbacterialcommunitystructuretheplanhabrandomizedtrialpilotstudy
AT bostjanmurovec hypoxiaandinactivityrelatedphysiologicalchangesprecedeortakeplaceinabsenceofsignificantrearrangementsinbacterialcommunitystructuretheplanhabrandomizedtrialpilotstudy
AT zalaprevorsek hypoxiaandinactivityrelatedphysiologicalchangesprecedeortakeplaceinabsenceofsignificantrearrangementsinbacterialcommunitystructuretheplanhabrandomizedtrialpilotstudy
AT matevzlikar hypoxiaandinactivityrelatedphysiologicalchangesprecedeortakeplaceinabsenceofsignificantrearrangementsinbacterialcommunitystructuretheplanhabrandomizedtrialpilotstudy
AT blazstres hypoxiaandinactivityrelatedphysiologicalchangesprecedeortakeplaceinabsenceofsignificantrearrangementsinbacterialcommunitystructuretheplanhabrandomizedtrialpilotstudy