In prospective human exploration of outer space the need to maintain a species over several generations under changed gravity conditions may arise. This paper reports the analysis of the third generation of fruit fly Drosophila melanogaster obtained during the 44.5-day space flight (Foton-M4 satellite 2014 Russia) followed by the fourth generation on Earth and the fifth generation under conditions of a 12-day space flight (2014 in the Russian Segment of the ISS). The obtained results show that it is possible to obtain the third-fifth generations of a complex multicellular Earth organism under changed gravity conditions (in the cycle weightlessness - Earth - weightlessness) which preserves fertility and normal development. However there were a number of changes in the expression levels and content of cytoskeletal proteins that are the key components of the spindle apparatus and the contractile ring of cells.

To understand how humans adapt to space environments many experiments can be conducted on astronauts while they work aboard the Space Shuttle or the International Space Station (ISS). We also need animal experiments that can apply to human models and help prevent or solve the physical issues we face in space travel. The medaka is a suitable model fish for studying space adaptation because in the second International Microgravity Laboratory mission in 1994 adult fish mated successfully in space during 15 days of flight. In 2012 another space experiment Medaka Osteoclast was performed. Male and female fish (6 weeks old at launching) were maintained in the Aquatic Habitat system for 2 months in the ISS. The RNA-seq analysis of tissues from these fish will revealed tissue-specific responsiveness and common stress responses during space adaptation.

Space travel presents unlimited opportunities for exploration and discovery but requires a more complete understanding of the immunological consequences of long-term exposure to the conditions of spaceflight. To understand these consequences better and to contribute to design of effective countermeasures we used the Drosophila model to compare innate immune responses to bacteria and fungi in flies that were either raised on earth or in outer space aboard the NASA Space Shuttle Discovery (STS-121). Microarrays were used to characterize changes in gene expression that occur in response to infection by bacteria and fungus in drosophila that were either hatched and raised in outer space (microgravity) or on earth (normal gravity). Whole Oregon R strain drosophila melanogaster fruit flies either raised on earth or in space that were (1) uninfected (2) infected with bacteria (Escherichia coli) or (3) infected with fungus (Beauveria bassiana) were used for RNA extraction and hybridization on Affymetrix microarrays.

This study presents the first global transcriptional profiling and phenotypic characterization of the major human opportunistic fungal pathogen, Candida albicans, grown in spaceflight conditions. Microarray analysis revealed that C. albicans subjected to short-term spaceflight culture differentially regulated 454 genes compared to synchronous ground controls, which represented 8.4% of the analyzed ORFs. Spaceflight-cultured C. albicans induced genes involved in cell aggregation (similar to flocculation), which was validated by microscopic and flow cytometry analysis. We also observed enhanced random budding of spaceflight-cultured cells as opposed to more normal bipolar budding patterns for ground samples, in accordance with the gene expression data. Furthermore, genes involved in antifungal agent and stress resistance were differentially regulated in spaceflight, including induction of ABC transporters and members of the major facilitator family, downregulation of ergosterol-encoding genes, and upregulation of genes involved in oxidative stress resistance. Finally, downregulation of genes involved in the actin cytoskeleton was observed. Interestingly, the transcriptional regulator Cap1 and over 30% of the Cap1 regulon was differentially expressed in spaceflight-cultured C. albicans. A potential role for Cap1 in the spaceflight response of C. albicans is suggested, as this regulator is involved in random budding, cell aggregation, actin cytoskeleton, and oxidative stress resistance; all related to observed spaceflight-associated changes of C. albicans. While culture of C. albicans in microgravity potentiates a global change in gene expression that could induce a virulence-related phenotype, no increased virulence in a murine intraperitoneal (i.p.) infection model was observed. This study represents an important basis for the assessment of the risk that commensal flora could play during spaceflight missions. Furthermore, since the low fluid-shear environment of microgravity is relevant to physical forces encountered by pathogens during the infection process, insights gained from this study could identify novel infectious disease mechanisms, with downstream benefits for the general public. Cells were grown for 24 hours on the space shuttle or as ground-based controls, preserved in RNALater, and stored at -80C. Four samples of each flight- and ground-based controls were harvested for microarray analysis. GAP is Group Activation Pack and each GAP contains 8 FPAs. The numbers represent the # assigned to the particular GAP and the number assigned to the specific FPA (1-8) within the indicated GAP. The same hardware is used for the flight samples and the ground samples.

Future space missions will include return to the Moon and long duration deep space roundtrip missions to Mars. Leaving the protection that Low Earth Orbit provides will unavoidably expose astronauts to higher cumulative doses of space radiation, in addition to other stressors, e.g. microgravity. Immune regulation is known to be impacted and it remains to be seen whether prolonged effects will be encountered in deep space that can have an adverse impact on health. In this study we investigated the effects in overall metabolism of three different low dose radiation exposures (γ-rays, 16O, and 56Fe) in spleen from male C57BL/6 mice at 1, 2, and 4 months after exposure. Forty metabolites were identified with significant enrichment in purine metabolism, tricarboxylic acid cycle, fatty acids, acylcarnitines, and amino acids. Early perturbations were more prominent in the γ irradiated samples, while longer term responses shifted towards the high energy particle effects. Regression analysis showed a positive correlation of fatty acids with time and negative association with γ-rays, while degradation of purines were positively associated with time. Taken together, there is a strong suggestion of mitochondrial implication and the possibility of long term effects in DNA repair and nucleotide pools following radiation exposure.

Spaceflight poses risks to the central nervous system (CNS), and understanding neurological responses is important for future missions. We report CNS changes in Drosophila aboard the International Space Station in response to spaceflight microgravity (SFμg) and artificially simulated Earth gravity (SF1g) via inflight centrifugation as a countermeasure. While inflight behavioral analyses of SFμg exhibit increased activity, postflight analysis displays significant climbing defects, highlighting the sensitivity of behavior to altered gravity. Multi-omics analysis shows alterations in metabolic, oxidative stress and synaptic transmission pathways in both SFμg and SF1g; however, neurological changes immediately postflight, including neuronal loss, glial cell count alterations, oxidative damage, and apoptosis, are seen only in SFμg. Additionally, progressive neuronal loss and a glial phenotype in SF1g and SFμg brains, with pronounced phenotypes in SFμg, are seen upon acclimation to Earth conditions. Overall, our results indicate that artificial gravity partially protects the CNS from the adverse effects of spaceflight. This study derives results from the in-flight video analysis (video recording assay).

Immune dysregulation is among the main adverse outcomes of spaceflight. Despite its crucial role in host protection effects on the human antibody repertoire are unknown. Consequently we examined the IgM repertoire of five cosmonauts 25 days before launch after 64 and 129 days spent on the International Space Station (ISS) and after 1 7 and 30 days of Earth reambulation using high-throughput sequencing. This is the first study of this kind. Our data revealed that the IgM repertoire of cosmonauts was different from the one of control subjects already prior to launch and that 2 out the 5 analyzed cosmonauts presented significant changes of their IgM repertoire during the mission. These modifications persisted up to 30 days after landing likely affected the specificities of IgM binding sites correlated with changes of the V(D)J recombination process in charge of creating functional antibody genes and coincided with a higher stress response. These data confirm that about half of the astronauts who spent six months on the ISS are subjected to immunological changes contribute to explain increased susceptibility to infection reveal individual responses and consequently that personalized approaches should be implemented during future deep-space exploration missions that will endure for an unprecedented amount of time.

The objective of the RR-23 mission was to better understand the effects of spaceflight on the eyes, specifically on the structure and function of the arteries, veins, and lymphatic vessels that are needed to maintain vision. To this end, twenty male, C57BL/6J, 16-17 weeks-old mice were delivered to the ISS on SpaceX-21 in a single transporter, transferred to two rodent habitats, and maintained in microgravity for 38 days. Flight mice were then returned to Earth alive (Jan 13th, 2021). After splashdown in the Atlantic Ocean, mice were transported to Kennedy Space Center via helicopter. The 20 Flight, 20 Habitat Ground Control (HGC), and 20 Vivarium Ground Control (VGC) mice were removed from Rodent Transporters (Flight and HGC) or vivarium cages (VGC), placed into shipping containers, and flown to Texas A and M University. There, mice underwent post-flight procedures, before euthanasia and tissue collection. Flight, HGC and VGC animals were euthanized and dissected on Jan 14th, 17th or 20th of 2021, respectively. Lungs were preserved by flash freezing in liquid nitrogen and stored at -80 ˚C until RNA was extracted, and libraries generated and sequenced (target 60 M clusters per sample, PE 150 bp). This dataset features 8 samples from the Flight group, 9 samples from the VGC group, and 6 samples from the HGC group.

Larvae-Pupae transition flies (Drosophila) were recovered and transport for 3 days at 12-14C to arrest development until the launch site then exposed to RT (18-20C) for some hours including the launch and trip to the International Space Station then pupae were exposed to microgravity in the ISS for 4 days and a half at 22C. Finally pupae were fixed on acetone and frozen until recovery on Earth. Four groups of samples: 1 ISS (+ground control) as described 2 RPM (microgravity simulator on Earth) as described 3 RPM without constrains (No MAMBA container and only 5 days exposure without cold transport) and 4 centrifuge 10g without constrains control.

The objective of the Rodent Research-23 missions (RR-23) was to better understand the effects of spaceflight on the eyes, specifically on the structure and function of the arteries, veins, and lymphatic vessels that are needed to maintain vision. To this end, twenty male, C57BL/6J, 16-17 weeks old mice were delivered to the ISS on SpaceX-21 in a single transporter, transferred to two rodent habitats, and maintained in microgravity for 38 days. Flight mice were then returned to Earth alive (Jan 13th, 2021). After splashdown in the Atlantic Ocean, mice were transported to Kennedy Space Center via helicopter. The 20 Flight, 20 Habitat Ground Control (HGC), and 20 Vivarium Ground Control (VGC) mice were removed from Rodent Transporters (Flight and HGC) or vivarium cages (VGC), placed into shipping containers, and flown to Texas A and M University. There, mice underwent post flight procedures, before euthanasia and tissue collection. Flight, HGC and VGC animals were euthanized and dissected on Jan 14th, 17th or 20th of 2021, respectively. Spleens were preserved by immersion in RNAlater and stored at -80C until RNA was extracted, and libraries generated and sequenced (target 60 M clusters per sample, PE 150 bp). This dataset features 9 samples from the Flight group, 10 samples from the HGC group, and 9 samples from the VGC group.