The JAXA MHU-2 mission had two objectives: 1) To increase understanding of effects of spaceflight on the gut environment (microbiota and metabolites) and immune system using multi-omics based analysis; 2) To evaluate whether fructo-oligosaccharides added to the diet as prebiotics improve the gut environment and immune function during spaceflight. Twelve 16-18 week old male C57BL/6J mice were singly housed in the JAXA Habitat Cage Units (HCUs) on the ISS for 30 days. Six flight mice were housed in microgravity while six were exposed to simulated 1g by centrifugation. These two flight groups were further divided in half so that three mice in each group received standard JAXA chow while the other three were fed chow supplemented with fructooligosaccharides (FOS). Mice were returned live and euthanized and dissected <1 day after splashdown. Ground controls (n=6) were asynchronous and housed in HCUs. Vivarium controls (n=6) were asynchronous and housed in standard habitats. Three ground control and three vivarium animals received standard chow while the other three each ground control and vivarium animals received FOS-supplemented chow. Ground and vivarium samples were dissected by a separate dissection team than flight samples. Femoral skin was dissected 30 minutes after euthanasia and snap frozen in liquid nitrogen. Total RNA was extracted and sequenced at a target depth of 60 M clusters per sample (ribodepleted paired end 150). Study Factor Levels: 1)Spaceflight ug Std. Chow: 3; 2)Spaceflight ug FOS: 3; 3) Spaceflight Artificial 1g Std. Chow: 3; 4)Spaceflight Artificial 1g FOS: 3; 5)Ground 1g Std. Chow: 3; 6)Ground 1g FOS: 3; 7)Vivarium 1g Std. Chow: 3; 8)Vivarium 1g FOS: 3

The objective of the Rodent Research-5 (RR-5) study was to evaluate bone loss in mice during spaceflight and to determine if treatment with a modified version of NEL-like molecule-1 (NELL-1) can reduce or prevent bone loss that would otherwise occur during spaceflight. To this end, a cohort of forty 30-weeks-old female BALB/cAnNTac mice were flown to the ISS and housed in the Rodent Habitat. Six days after launch half of the mice were treated with NELL-1 (10 mg/kg in 0.3 ml PBS), while the other half were treated with vehicle control (0.3 ml PBS). Fourteen days after launch animals were again treated with NELL-1 or vehicle control as before, except that all animals were also injected with the bone marker, calcein green (20 mg/kg in 0.1 ml). Injections of vehicle, NELL-1, and bone markers were intraperitoneal. After all forty mice on orbit received two treatments; ten control mice and ten experimental mice were randomly selected for live animal return (LAR). At approximately 30 days after launch the twenty LAR mice were transported live back to Earth. Animals were allowed to recover for 30 days in standard habitats before euthanasia via intraperitoneal injection with ketamine/xylazine. During the recovery, the animals received another two treatments. GeneLab received RNA later preserved femoral skin from nine live animal return and ten matching ground control mice. These were from the vehicle control animals only. RNA was extracted, libraries generated (stranded, ribodepleted) and sequenced (target 60 M clusters at PE 150 bp).

The objective of the Rodent Research-5 (RR-5) study was to evaluate bone loss in mice during spaceflight and to determine if treatment with a modified version of NEL-like molecule-1 (NELL-1) can reduce or prevent bone loss that would otherwise occur during spaceflight. To this end a cohort of forty 30-weeks-old female BALB/cAnNTac mice were flown to the ISS and housed in the Rodent Habitat. Six days after launch half of the mice were treated with NELL-1 (10 mg/kg in 0.3 ml PBS) while the other half were treated with vehicle control (0.3 ml PBS). Fourteen days after launch animals were again treated with NELL-1 or vehicle control as before except that all animals were also injected with the bone marker calcein green (20 mg/kg in 0.1 ml). Injections of vehicle NELL-1 and bone markers were intraperitoneal. After all forty mice on orbit received two treatments; ten control mice and ten experimental mice were randomly selected for live animal return (LAR). At approximately 30 days after launch the twenty LAR mice were transported live back to Earth. Animals were allowed to recover for 30 days in standard habitats before euthanasia via intraperitoneal injection with ketamine/xylazine. During the recovery the animals received another two treatments. GeneLab received RNA later preserved femoral skin from nine live animal return and ten matching ground control mice. These were from the vehicle control animals only. RNA was extracted libraries generated (stranded ribodepleted) and sequenced (target 60 M clusters at PE 150 bp).

In the Rodent Research Reference Mission (RRRM-2), forty female C57BL/6NTac mice were flown on the International Space Station. To assess differences in outcomes due to age, twenty 12 week-old and twenty 29 week-old mice were flown, respectively. To directly assess spaceflight effects, half of the young and old mice (10 old, 10 young) were sacrificed on-orbit after 55-58 days (ISS Terminal, ISS-T), while the other half (10 old, 10 young) were returned live to Earth after 32 days and allowed to recover for 24 days (Live Animal Return, LAR) before sacrifice. ISS-T and LAR mice were the same age at sacrifice. Both the ISS-T and LAR animals had independent ground controls (10 mice per group housed in flight hardware in matched environmental conditions), basal controls (10 mice per group sacrificed 2 days before launch), and vivarium controls (10 mice per group housed within standard vivarium habitats). Thus RRRM-2 included a total of 160 mice. This study includes single cell transcriptional profiling data from femur bone marrow from 4 young LAR flight animals, 4 old LAR flight animals, 4 young LAR ground control animals, and 4 old LAR ground control animals.

Understanding the axis of the human microbiome and physiological homeostasis is an essential task in managing deep-space travel associated health risks. The NASA led Rodent Research 5 mission enabled an ancillary investigation of the gut microbiome varying exposure to microgravity (flight) relative to ground controls in the context of previously shown bone mineral density (BMD) loss that was observed in these flight groups. We demonstrate elevated abundance of Lactobacillus murinus and Dorea sp. during microgravity exposure relative to ground control through whole genome sequencing and 16S rRNA analyses. Specific functionally assigned gene clusters of Lactobacillus murinus and Dorea sp. capable of producing metabolites, lactic acid, leucine/isoleucine, and glutathione are enriched. These metabolites are elevated in the microgravity-exposed host serum through LC-MS/MS metabolomic analysis. Along with BMD loss, ELISA analysis reveals increases of osteocalcin and reductions in tartrate-resistant acid phosphatase 5b signifying additional loss of bone homeostasis in flight.

The objective of the Rodent Research-9 (RR-9) mission was to use mice to understand the molecular basis of phenomena that affect astronauts during long-duration spaceflight particularly visual impairment and joint tissue degradation. To this end a flight group (FLT) of 10-week-old male C57BL/6J mice was launched from Kennedy Space Center (KSC) on 8/14/2017 and housed in Rodent Habitats on the ISS for 33 days before being returned alive to Earth. After splashdown in the Pacific Ocean the animals were transported to Loma Linda University (LLU) for testing euthanasia and dissection on 9/18/2018. A Basal Control (BSL) was housed in standard cages at Kennedy Space Center (KSC) and euthanized one day after launch of the FLT animals (8/15/2017). Ground Control (GC) and Vivarium Control (VIV) studies were planned to commence at KSC approximately one-week after the conclusion of the flight experiments. However all the GC and VIV mouse studies at KSC had to be cancelled due to Hurricane Irma and potential adverse effects on the animal housing facility. The GC and VIV studies were therefore rescheduled and begun in May 2018. The GC was euthanized and dissected 6/18/2018 - 6/20/2018 while the VIV was euthanized and dissected 6/22/2018 - 6/23/2018. Because this resulted in a different cohort of mice being used for the GC and VIV controls as compared to the flight (FLT) and basal (BSL) groups two cohort controls were included in the study. The first Cohort Control 1 (CC_C1) was from the same cohort as the FLT and BSL animals and was sacrificed and dissected 4 days after the FLT group (9/22/2017). The second Cohort Control 2 (CC_C2) was from the same cohort as the GC and VIV animals and was sacrificed and dissected 2-8 days after the GC and VIV groups (6/24/2018 - 6/26/2018). The CC_C1 and CC_C2 groups were housed in standard cages and fed standard chow in contrast to all other groups which received Rodent Foodbars. To clarify the connections between treatment groups and animal cohorts the following group abbreviations are used in the sample metadata: Flight (FLT_C1); Basal (BSL_C1); Ground Control (GC_C2); Vivarium Control (VIV_C2) Cohort Control 1 (CC_C1); Cohort Control 2 (CC_C2). Fecal pellets were isolated directly from mice during dissection and preserved by flash freezing in liquid nitrogen before stored at -80 C. DNA was then extracted shotgun metagenomic libraries generated and libraries sequenced (target 10 M clusters at PE 250 bp). Metagenomic data was generated from the following groups: Basal Control (n=5) Ground Control (n=5) Vivarium Control (n=5) Cohort Control 1 (n=5) Cohort Control 2 (n=5) Flight (n=5).

The JAXA MHU-2 mission had two objectives: 1) To increase understanding of effects of spaceflight on the gut environment (microbiota and metabolites) and immune system using multi-omics based analysis; 2) To evaluate whether fructo-oligosaccharides added to the diet as prebiotics improve the gut environment and immune function during spaceflight. Twelve 16-18 week old male C57BL/6J mice were singly housed in the JAXA Habitat Cage Units (HCUs) on the ISS for 30 days. Six flight mice were housed in microgravity while six were exposed to simulated 1g by centrifugation. These two flight groups were further divided in half so that three mice in each group received standard JAXA chow while the other three were fed chow supplemented with fructooligosaccharides (FOS). Mice were returned live and euthanized and dissected <1 day after splashdown. Ground controls (n=6) were asynchronous and housed in HCUs. Vivarium controls (n=6) were asynchronous and housed in standard habitats. Three ground control and three vivarium animals received standard chow while the other three each ground control and vivarium animals received FOS-supplemented chow. Ground and vivarium samples were dissected by a separate dissection team than flight samples. Dorsal skin was dissected 30 minutes after euthanasia and snap frozen in liquid nitrogen. Total RNA was extracted and sequenced at a target depth of 60 M clusters per sample (ribodepleted paired end 150). Study Factor Levels: 1)Spaceflight ug Std. Chow: 3; 2)Spaceflight ug FOS: 3; 3) Spaceflight Artificial 1g Std. Chow: 3; 4)Spaceflight Artificial 1g FOS: 3; 5)Ground 1g Std. Chow: 3; 6)Ground 1g FOS: 3; 7)Vivarium 1g Std. Chow: 3; 8)Vivarium 1g FOS: 3.

The objective of the Rodent Research-5 (RR-5) study was to evaluate bone loss in mice during spaceflight and to determine if treatment with a modified version of NEL-like molecule-1 (NELL-1) can reduce or prevent bone loss that would otherwise occur during spaceflight. To this end, a cohort of forty 30-weeks-old female BALB/cAnNTac mice were flown to the ISS and housed in the Rodent Habitat. Six days after launch half of the mice were treated with NELL-1 (10 mg/kg in 0.3 ml PBS), while the other half were treated with vehicle control (0.3 mls PBS). Fourteen days after launch animals were again treated with NELL-1 or vehicle control as before, except that all animals were also injected with the bone marker, calcein green (20 mg/kg in 0.1 ml). Injections of vehicle, NELL-1, and bone markers were intraperitoneal. After all forty mice on orbit received two treatments; ten control mice and ten experimental mice were randomly selected for live animal return (LAR). At approximately 30 days after launch the twenty LAR mice were transported live back to Earth. Animals were allowed to recover for 30 days in standard habitats before euthanasia via intraperitoneal injection with ketamine/xylazine. During the recovery, the animals received another two treatments. GeneLab received RNA later preserved dorsal skin from ten live animal return and ten matching ground control mice. These were from the vehicle control animals only. RNA was extracted, libraries generated (stranded, ribodepleted) and sequenced (target 60 M clusters at PE 150 bp).

The objective of the Rodent Research-5 (RR-5) study was to evaluate bone loss in mice during spaceflight and to determine if treatment with a modified version of NEL-like molecule-1 (NELL-1) can reduce or prevent bone loss that would otherwise occur during spaceflight. To this end a cohort of forty 30-weeks-old female BALB/cAnNTac mice were flown to the ISS and housed in the Rodent Habitat. Six days after launch half of the mice were treated with NELL-1 (10 mg/kg in 0.3 ml PBS) while the other half were treated with vehicle control (0.3 mls PBS). Fourteen days after launch animals were again treated with NELL-1 or vehicle control as before except that all animals were also injected with the bone marker calcein green (20 mg/kg in 0.1 ml). Injections of vehicle NELL-1 and bone markers were intraperitoneal. After all forty mice on orbit received two treatments; ten control mice and ten experimental mice were randomly selected for live animal return (LAR). At approximately 30 days after launch the twenty LAR mice were transported live back to Earth. Animals were allowed to recover for 30 days in standard habitats before euthanasia via intraperitoneal injection with ketamine/xylazine. During the recovery the animals received another two treatments. GeneLab received RNA later preserved dorsal skin from ten live animal return and ten matching ground control mice. These were from the vehicle control animals only. RNA was extracted libraries generated (stranded ribodepleted) and sequenced (target 60 M clusters at PE 150 bp).

Comparitive gene expression in skin between mice maintained in microgravity (0g) and normogravity (1g) environment. Six male C57Bl/J10 mice were housed for 91 days in the specially designed Mouse Drawer System in weightlessness aboard the International Space Station. Three wild-type mice (WT) and three transgenic mice overexpressing the osteogneic factor PTN/OSF1 under the control of the human bone specific ostecalcin promoter (Tg) were used in the experiment. During the 3-month stay on the ISS 3 mice unfortunately died leaving 2 Tg and 1 WT. MDS tissue sharing program allowed several teams to study various tissues from these mice. Our aim was to investigate the effect of such a long period of microgravity on skin physiology by morphological biochemical and genomewide analyses by comparison to similar mice on ground. Gene expression in the skin of 3 space mice and of 3 ground mice was analyzed by microarray. As this unique experiment performed on 3 mice limits the power of statistical analyis as the transgene PTN/OSF1 was not overexpressed in skin and as a pair wise Pearson s correlation rates between the individual levels of expressed transcripts in the WT and the Tg mice were not significantly different from each other in one experimental group (space or ground) data from the 3 mice were combined to compare results from the space an ground groups.