Spaceflight is a unique environment with profound effects on biological systems including tissue redistribution and musculoskeletal stresses. However the more subtle biological effects of spaceflight on cells and organisms are difficult to measure in a systematic unbiased manner. Here we test the utility of the molecularly barcoded yeast deletion collection to provide a quantitative assessment of the effects of microgravity on a model organism. We developed robust hardware to screen in parallel the complete collection of ~4800 homozygous and ~5900 heterozygous (including ~1100 single-copy deletions of essential genes) yeast deletion strains each carrying unique DNA that acts as strain identifiers. We compared strain fitness for the homozygous and heterozygous yeast deletion collections grown in spaceflight and ground as well as plus and minus hyperosmolar sodium chloride providing a second additive stressor. The genome-wide sensitivity profiles obtained from these treatments were then queried for their similarity to a compendium of drugs whose effects on the yeast collection have been previously reported. We found that the effects of spaceflight have high concordance with the effects of DNA-damaging agents and changes in redox state suggesting mechanisms by which spaceflight may negatively affect cell fitness.

Spaceflight is a unique environment with profound effects on biological systems including tissue redistribution and musculoskeletal stresses. However the more subtle biological effects of spaceflight on cells and organisms are difficult to measure in a systematic unbiased manner. Here we test the utility of the molecularly barcoded yeast deletion collection to provide a quantitative assessment of the effects of microgravity on a model organism. We developed robust hardware to screen in parallel the complete collection of ~4800 homozygous and ~5900 heterozygous (including ~1100 single-copy deletions of essential genes) yeast deletion strains each carrying unique DNA that acts as strain identifiers. We compared strain fitness for the homozygous and heterozygous yeast deletion collections grown in spaceflight and ground as well as plus and minus hyperosmolar sodium chloride providing a second additive stressor. The genome-wide sensitivity profiles obtained from these treatments were then queried for their similarity to a compendium of drugs whose effects on the yeast collection have been previously reported. We found that the effects of spaceflight have high concordance with the effects of DNA-damaging agents and changes in redox state suggesting mechanisms by which spaceflight may negatively affect cell fitness.

Upon weightlessness and microgravity deleterious effects on the neurosensory and neurovestibular systems haematological changes and deconditioning of musculoskeletal cardiovascular and cardiopulmonary functions have been reported. In particular loss of muscle mass and strength are triggered by weightlessness in humans during space flights that is similarly observed as a result of physical inactivity conditions and aging on Earth. However skeletal muscle tissue is of paramount importance for health maintenance (e.g. being essential to locomotion heat production and metabolism). To better prevent or eventually treat microgravity-induced muscle atrophy its underlying mechanisms have first to be characterized in detail. Using cutting-edge quantitative proteomics the aim of the present study was therefore to get an in depth view of the molecular regulations triggered by space conditions in skeletal muscles of mice during the 30-day flight of the BION-M1 biosatellite. As muscles differing in their fiber type composition appear to respond differently to microgravity (see above) we characterized here the differential response of the soleus extensor digitorum longus and vastus lateralis muscles.

Upon weightlessness and microgravity deleterious effects on the neurosensory and neurovestibular systems haematological changes and deconditioning of musculoskeletal cardiovascular and cardiopulmonary functions have been reported. In particular loss of muscle mass and strength are triggered by weightlessness in humans during space flights that is similarly observed as a result of physical inactivity conditions and aging on Earth. However skeletal muscle tissue is of paramount importance for health maintenance (e.g. being essential to locomotion heat production and metabolism). To better prevent or eventually treat microgravity-induced muscle atrophy its underlying mechanisms have first to be characterized in detail. Using cutting-edge quantitative proteomics the aim of the present study was therefore to get an in depth view of the molecular regulations triggered by space conditions in skeletal muscles of mice during the 30-day flight of the BION-M1 biosatellite. As muscles differing in their fiber type composition appear to respond differently to microgravity (see above) we characterized here the differential response of the soleus extensor digitorum longus and vastus lateralis muscles.

['Microgravity is one of the most important features in spaceflight. Previous evidence has shown that significant changes to the musculoskeletal and immune systems occurred under microgravity. The present study was undertaken to explore the change in protein abundance in human colon colorectal cells that were incubated for 48 or 72 h either in normal conditions and µG simulated conditions. The comparative proteomic method based on the 18O labeling technique was applied to investigate the up-regulated proteins and down-regulated proteins in SH-SY5Y under simulated microgravity.']

Adaptation of humans in low gravity conditions is a matter of utmost importance when efforts are on to a gigantic leap in human space expeditions for tourism and formation of space colonies. In this connection cardiovascular adaptation in low gravity is a critical component of human space exploration. Deep high-throughput sequencing approach allowed us to analyze the miRNA and mRNA expression profiles in human umbilical cord vein endothelial cells (HUVEC) cultured under gravity (G) and stimulated microgravity (MG) achieved with a clinostat. The present study identified totally 1870 miRNAs differentially expressed in HUVEC under MG condition when compared to the cells subjected to unitary G conditions. The functional association of identified miRNAs targeting specific mRNAs revealed that miRNAs hsa-mir-496 hsa-mir-151a hsa-miR-296-3p hsa-mir-148a hsa-miR-365b-5p hsa-miR-3687 hsa-mir-454 hsa-miR-155-5p and hsa-miR-145-5p differentially regulated the genes involved in cell adhesion angiogenesis cell cycle JAK-STAT signaling MAPK signaling nitric oxide signaling VEGF signaling and wound healing pathways. Further the q-PCR based experimental studies of upregulated and downregulated miRNA and mRNAs demonstrate that the above reported miRNAs influence the cell proliferation and vascular functions of the HUVEC in MG conditions effectively. Consensus on the interactome results indicates restricted fluctuations in the transcriptome of the HUVEC exposed to short-term MG that could lead to higher levels of endothelial functions like angiogenesis and vascular patterning.

Microphysiological systems provide the opportunity to model accelerated changes at the human tissue level in the extreme space environment. Spaceflight-induced muscle atrophy experienced by astronauts shares similar physiological changes to muscle wasting in older adults, known as sarcopenia. These shared attributes provide a rationale for investigating molecular changes in muscle cells exposed to spaceflight that may mimic the underlying pathophysiology of sarcopenia. We report the results from three-dimensional myobundles derived from muscle biopsies from young and older adults, integrated into an autonomous CubeLab™, and flown to the International Space Station (ISS) aboard SpaceX CRS-21 as part of the NIH/NASA funded Tissue Chips in Space program. Global transcriptomic RNA-Seq analyses comparing the myobundles in space and on the ground revealed downregulation of shared transcripts related to myoblast proliferation and muscle differentiation. The analyses also revealed downregulated differentially expressed gene pathways related to muscle metabolism unique to myobundles derived from the older cohort exposed to the space environment compared to ground controls. Gene classes related to inflammatory pathways were downregulated in flight samples cultured from the younger cohort compared to ground controls. Our muscle tissue chip platform provides an approach to studying the cell autonomous effects of spaceflight on muscle cell biology that may not be appreciated on the whole organ or organism level and sets the stage for continued data collection from muscle tissue chip experimentation in microgravity. We also report on the challenges and opportunities for conducting autonomous tissue-on-chip CubeLab™ payloads on the ISS.

Exposure to weightlessness in microgravity and elevated space radiation are associated with rapid bone loss in mammals, but questions remain about their mechanisms of action and relative importance. In this study, we tested the hypothesis that bone loss during spaceflight in Low Earth Orbit is primarily associated with site-specific microgravity unloading of weight-bearing sites in the skeleton. Microcomputed tomography and histological analyses of bones from mice space flown on ISS for 37 days in the NASA Rodent Research-1 experiment show significant site-specific cancellous and cortical bone loss occurring in the femur, but not in L2 vertebrae. The lack of bone degenerative effects in the spine in combination with same-animal paired losses in the femur suggests that space radiation levels in Low Earth Orbit or other systemic stresses are not likely to significantly contribute to the observed bone loss. Remarkably, spaceflight is also associated with accelerated progression of femoral head endochondral ossification. This suggests the microgravity environment promotes premature progression of secondary ossification during late stages of skeletal maturation at 21 weeks. Furthermore, mice housed in the NASA ISS Rodent Habitat during 1g ground controls maintained or gained bone relative to mice housed in standard vivarium cages that showed significant bone mass declines. These findings suggest that housing in the Rodent Habitat with greater topological enrichment from 3D wire-mesh surfaces may promote increased mechanical loading of weight-bearing bones and maintenance of bone mass. In summary, our results indicate that in female mice approaching skeletal maturity, mechanical unloading of weight-bearing sites is the major cause of bone loss in microgravity, while sites loaded predominantly by muscle activity, such as the spine, appear unaffected. Additionally, we identified early-onset of femoral head epiphyseal plate secondary ossification as a novel spaceflight skeletal unloading effect that may lead to premature long bone growth arrest in microgravity. This study derives results from femur and vertebrae using the micro computed tomography assay.

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.

Given the limited knowledge of the biological impact of spaceflight a multi-omics systems biology approach was used to investigate NASA xe2 x80 x99s GeneLab data and astronaut biomedical profiles. These data consist of hundreds of samples flown in space human metrics from 59 astronauts and confirmatory data from NASA xe2 x80 x99s Twin Study analyzed together for consistent transcriptomic proteomic metabolomic and epigenetic response to spaceflight. Pathway analysis showed significant enrichment of mitochondrial activity and innate immunity. Muscle and liver tissues showed that chronic inflammation may be a response to mitochondrial dysfunction. Additional pathways altered in spaceflight included cell cycle circadian rhythm and olfactory activity pathways all of which are known to have interactions with mitochondrial activity. Evidence of altered mitochondrial function was also found in the urine and blood metabolic data compiled from the astronaut cohort and NASA Twin Study data all of which indicate mitochondrial stress as a consistent phenotype of spaceflight.