Probiotics on Immune Function and Intestinal Microbiota in Astronauts Under Closed Microgravity Environment

Not Applicable

• Conditions: Immune Function and Intestinal Microbiota
• Interventions: Dietary Supplement: Probiotic capsule

• Registration Number: NCT02618005
• Lead Sponsor: Yakult Honsha Co., LTD

Brief Summary

Human immune function and intestinal microbiota are suggested to be altered within long-duration stay in space. Accumulated evidences on earth support that Lactobacillus casei strain Shirota (LcS) is a promising probiotic strain on improvement of immune function and intestinal microbiota. This study aims to investigate the impact of long-duration spaceflight as well as intake of LcS on the international space station (ISS), on immune system and intestinal microbiota in astronauts.

Detailed Description

Not available

Study Timeline

• Study Start: 2015-10
• Study First Submitted: 2015-11-01
• Study First Submitted QC: 2015-11-25
• Study First Posted: 2015-12-01
• Status Verified: 2021-08
• Last Update Submitted: 2021-08-25
• Last Update Posted: 2021-08-27
• Primary Completion: 2023-03
• Study Completion: 2023-03

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 10

Inclusion Criteria

• Individuals who are scheduled to stay on the ISS for at least 3 months
• Individuals who fully understand the study protocol and provide written informed consent for the study participation

Exclusion Criteria

• Individuals who routinely use antibiotic, laxative, and/or bowel regulating medicine
• Individuals who participate in other research that competes with this study in terms of the purpose and field, e.g., study with dietary management or intake of bifidobacteria/lactic acid bacteria, oligosaccharides, antibiotic, laxative, and/or bowel regulating medicine

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
LcS group	Probiotic capsule	Consuming probiotic capsule

Primary Outcome Measures

Name	Time	Method
Longitudinal changes in the number of LcS in feces	9-18 months	Number of LcS in feces will be assessed by PMA-qPCR, during pre-flight, in-flight and post-flight.
Longitudinal changes in the level of immune markers	9-18 months	Levels of immune markers in blood/saliva will be assessed by ELISA and bioassay, during pre-flight, in-flight and post-flight.
Longitudinal changes in numbers and composition of intestinal microbiota	9-18 months	Numbers and composition of bacteria in feces will be assessed by RT-qPCR/qPCR and next generation sequencer analysis, during pre-flight, in-flight and post-flight.

Trial Locations

Locations (1)

Japan Aerospace Exploration Agency; 🇯🇵 Ibaraki, Japan