The objective of the Rodent Research-10 mission (RR-10) was to investigate how spaceflight affects the cellular and molecular mechanisms of normal bone tissue regeneration in space. To this end, ten (10) 14-15 weeks-old female B6129SF2/J Wild Type (WT), and ten (10) 14-15 weeks-old female B6;129S2-Cdkn1atm1Tyj/J (p21-null) mice received a pre-flight subcutaneous injection of the bone marker (Alizarin Red), and were then delivered to the ISS aboard SpaceX-21. At 7 days before euthanasia, all 20 mice received an intraperitoneal (IP) injection with a bone formation marker (Calcein). At 48 +/- 2 hours before euthanasia, all 20 mice received an IP injection with a second dose of Calcein as well as a cell proliferation marker (BrdU). Then, following 28-29 days in microgravity, the Flight mice were euthanized. Following removal of hindlimbs, carcasses were wrapped in aluminum foil, preserved in the CryoChiller, and stored at -80 C or colder until return to Earth. In addition to the Flight group, three ground control groups were also part of the study: Basal (representing the pre-launch state), Vivarium (standard vivarium housing for the same duration of time as flight), and Ground (flight habitat in the International Space Station Environment Simulator, ISSES). Twenty mice (10 of each strain) were included in each of these control groups (except Vivarium which included 12 of each strain). These were treated, euthanized and processed on the same schedule and in the same manner as the flight samples. This study includes bulk RNA sequencing and spatially resolved transcriptional profiling data from hippocampi from 5 WT flight animals and 5 WT ground control animals. Hippocampi from the right hemisphere were embedded and cryosectioned. Cryosections were either processed for bulk RNA sequencing or placed on gene expression arrays, stained and imaged. Imaging was followed by tissue permeabilization to release mRNA molecules from cells for capture onto the array surface. Subsequently, spatial transcriptomics libraries were prepared and sequenced.

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-10 Mission (RR-10) was to investigate how spaceflight affects the cellular and molecular mechanisms of normal bone tissue regeneration in space. To this end, ten (10) 14-15 weeks-old female B6129SF2/J Wild Type (WT), and ten (10) 14-15 weeks-old female B6;129S2-Cdkn1atm1Tyj/J (p21-null) mice received a pre-flight subcutaneous injection of the bone marker (Alizarin Red), and were then delivered to the ISS aboard SpaceX-21. At 7 days before euthanasia, all 20 mice received an intraperitoneal (IP) injection with a bone formation marker (Calcein). At 48 +/- 2 hours before euthanasia, all 20 mice received an IP injection with a second dose of Calcein as well as a cell proliferation marker (BrdU). Then, following 28-29 days in microgravity, the Flight mice were euthanized. Following removal of hindlimbs, carcasses were wrapped in aluminum foil, preserved in the CryoChiller, and stored at -80 C or colder until return to Earth. In addition to the Flight group, three ground control groups were also part of the study: Basal (representing the pre-launch state), Vivarium (standard vivarium housing for the same duration of time as flight), and Ground (flight habitat in the International Space Station Environment Simulator, ISSES). Twenty mice (10 of each strain) were included in each of these control groups (except Vivarium which included 12 of each strain). These were treated, euthanized and processed on the same schedule and in the same manner as the flight samples. At the end of RR-10 experiment, all frozen carcasses were partially thawed and kidney tissues were removed and preserved by flash freezing in LN2. Kidneys were kept at -80 C freezer until processing. To ensure that both transcriptional profiling and protein expression profiling datasets are representative of the entire kidney, whole kidneys were first pulverized into a fine powder on dry ice. This powder was then split into two equal fractions with half being used for RNA isolation and half being used for protein isolation. RNA was used to generate three different transcriptional profiling datasets: a 3' tag-Seq datasets (20 M clusters at SE 93 bp), a polyA enriched dataset (60 M clusters at PE 150 bp), and a ribodepleted dataset (60 M clusters at PE 150 bp). Protein was used to generate protein expression profiling, and phosphoprotein profiling using the iTRAQ method (Isobaric tags for relative and absolute quantitation). Transcriptional profiling dataset features WT samples from the Flight, Ground, Basal and Vivarium groups. Protein expression profiling and phosphoprotein profiling datasets exclude the Vivarium group.

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 Rodent Research-3 (RR-3) mission was sponsored by the pharmaceutical company Eli Lilly and Co. and the Center for the Advancement of Science in Space to study the effectiveness of a potential countermeasure for the loss of muscle and bone mass that occurs during spaceflight. Twenty BALB/c, 12-weeks old female mice (ten controls and ten treated) were flown to the ISS and housed in the Rodent Habitat for 39-42 days. Twenty mice of similar age, and matching sex and strain were used for ground controls housed in identical hardware and matching ISS environmental conditions. Basal controls were housed in standard vivarium cages. Spaceflight, ground controls and basal groups had blood collected, then were euthanized, had one hind limb removed, and finally whole carcasses were stored at -80 C until dissection. All mice in this data set received only the control/sham injection. Brain samples from three flight and three ground control animal groups were cut in half between hemispheres. One hemisphere of each brain was used for generating spatially resolved transcriptional profiling data. Hemispheres were cryosectioned so that 2 consecutive sections from the hippocampus of each brain was placed on Visium Gene Expression arrays. Samples were fixed, stained with Hematoxylin and Eosin and imaged. Imaging was followed by tissue permeabilization to release mRNA molecules from cells for capture onto the array surface. Subsequently, following the 10XGenomics Visium Gene Expression protocol, Spatial Transcriptomics RNA-seq libraries were prepared and sequenced. The other hemisphere of each brain was used for single nuclei RNA-seq and ATAC-seq using the 10X Multiome protocol. In addition, bulk RNA-seq (ribodepleted, target depth of 60 M clusters, PE 150 bp) was performed from a pool of RNA extracted from 10-20 sections from each of 3 flight and 3 ground control samples.

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 bulk RNA sequencing and spatially resolved transcriptional profiling data from hippocampi from 5 old ISS-T flight animals, 3 old ISS-T ground control (GC) animals, 4 (bulk RNAseq) or 5 (spatial transcriptomics) young ISS-T flight animals, 3 young ISS-T GC animals, 3 old LAR flight animals, 3 old LAR GC animals, 3 young LAR flight animals, and 3 young LAR GC animals. Hippocampi from the right hemisphere were either processed for bulk RNA sequencing or embedded and cryosectioned. Cryosections were placed on gene expression arrays, stained and imaged. Imaging was followed by tissue permeabilization to release mRNA molecules from cells for capture onto the array surface. Subsequently, spatial transcriptomics libraries were prepared and sequenced.

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.

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-7 mission (RR-7) was to study the impact of the space environment on the gut microbiota of two strains of mice and how any changes in-turn affect the immune system metabolic system and circadian or daily rhythms. To this end ten 11-week-old female C57BL/6J and ten 11-week-old female C3H/HeJ mice were flown to the International Space Station on June 29 2018 on SpaceX-15 and housed in two Rodent Habitats. Samples of food swabs from living surfaces and fecal pellets were collected from each animal before launch and regularly during the mission. The mission also involved extended video collection (48 hr video segments per Habitat) to monitor circadian rhythms and on-orbit mass measurement. After 25 days on-orbit half of the mice of each strain were euthanized on the ISS with Ketamine/Xylazine/Acepromazine and cardiac puncture after which carcasses were segmented in three sections and preserved in RNA later. After 75-76 days the remaining 5 animals from each group were euthanized and processed in the same manner. The 25-day dissected carcasses returned on SpX-15 and the 75-day dissected carcasses returned on SpX-16. In addition to the Flight group three ground control groups were also part of the study: Basal (representing the pre-launch state) Vivarium (standard vivarium housing for the same duration of time as flight) and Ground (same habitat in the International Space Station Environment Simulator ISSES). Twenty mice (10 of each strain) were included in each of these control groups which were euthanized and processed on the same schedule and in the same manner as the flight samples. Dissections for tissues from all experimental groups were completed by the PI groups along with NASA s Biospecimen Sharing Program in February 2019. GeneLab received dorsal skin samples from forty C57BL/6J mice: 10 Basal 5 Ground (25 days) 5 Ground (75 days) 5 Flight (25 days) 5 Flight (75 days) 5 Vivarium (25 days) 5 Vivarium (75 days). GeneLab received dorsal skin samples from forty C3H/HeJ mice: 10 Basal 5 Ground (25 days) 5 Ground (75 days) 5 Flight (25 days) 5 Flight (75 days) 5 Vivarium (25 days) 5 Vivarium (75 days). From these skin samples RNA was extracted libraries generated (stranded ribodepleted) and sequenced (target 60 M clusters at PE 98 bp).

The health risk from spaceflight-induced neuronal damage and potential adverse neurovascular effects is a chief concern. More recently, it has been proposed that neuroinflammatory response plays an important role in the neurovascular remodeling in the brain after stress. The goal of the present study was to characterize changes in the gene expression of neuroinflammation panel for inflammation, neuronal function, metabolism and stress in mouse brain tissue. Ten-week old male C57BL/6 mice were launched to the International Space Station (ISS) on Space-X 12 for a 35-day mission. Within 38+4 hours of splashdown, mice were returned to Earth alive. Brain tissues were collected for analysis. Habitat ground control (GC) mice were maintained on Earth in flight hardware cages. A novel digital color-coded barcode counting technology (NanoStringTM) was used to evaluate gene expression profiles in the spaceflight mouse brain. The Neuroinflammation panel includes 757 genes covering the core pathways and processes that define neuroimmune interactions. A set of 54 differently expressed genes (p less than 0.05) significantly segregates the GC group from flight (FLT) group. Many pathways associated with cellular stress, inflammation, apoptosis, and metabolism were significantly altered by flight conditions. Genes supporting neuronal synaptic signaling and migration were significantly downregulated in FLT compared to the GC mice. A decrease in the expression of genes important for oligodendrocyte differentiation and myelin sheath maintenance was observed. Moreover, mRNA expression of many genes related to antiviral signaling, reactive oxygen species (ROS) generation, and bacterial immune response were significantly downregulated. These data indicate that neuroinflammation and altered immune reactions may be closely associate with spaceflight-induced stress response and have an impact on the neuronal function that may result in chronic neuroinflammation and late neurodegeneration. A total of 12 frozen right caudal half hemispheres containing mid- and hindbrain from GC and FLT mice (n equals 6 per group), were used for analysis