Temporal dynamics of the gut microbiota in people sharing a confined environment, a 520-day ground-based space simulation, MARS500

摘要

Background: The intestinal microbial communities and their temporal dynamics are gaining increasing interest due\udto the significant implications for human health. Recent studies have shown the dynamic behavior of the gut\udmicrobiota in free-living, healthy persons. To date, it is not known whether these dynamics are applicable during\udprolonged life sharing in a confined and controlled environment.\udResults: The MARS500 project, the longest ground-based space simulation ever, provided us with a unique\udopportunity to trace the crew microbiota over 520 days of isolated confinement, such as that faced by astronauts in\udreal long-term interplanetary space flights, and after returning to regular life, for a total of 2 years. According to our\uddata, even under the strictly controlled conditions of an enclosed environment, the human gut microbiota is\udinherently dynamic, capable of shifting between different steady states, typically with rearrangements of\udautochthonous members. Notwithstanding a strong individuality in the overall gut microbiota trajectory, some key\udmicrobial components showed conserved temporal dynamics, with potential implications for the maintenance of a\udhealth-promoting, mutualistic microbiota configuration.\udConclusions: Sharing life in a confined habitat does not affect the resilience of the individual gut microbial\udecosystem, even in the long term. However, the temporal dynamics of certain microbiota components should be\udmonitored when programming future mission simulations and real space flights, to prevent breakdowns in the\udmetabolic and immunological homeostasis of the crewmembers.