With extended stays aboard the International Space Station (ISS) becoming commonplace there is a need to better understand the effects of microgravity on cardiac function. We utilized human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) to study the effects of microgravity on cell-level cardiac function and gene expression. The hiPSC-CMs were cultured aboard the ISS for 5.5 weeks and their gene expression structure and functions were compared to ground control hiPSC-CMs. Exposure to microgravity on the ISS caused alterations in hiPSC-CM calcium handling. RNA-sequencing analysis demonstrated 2,635 genes were differentially expressed among flight post-flight and ground control samples including genes involved in mitochondrial metabolism. This study represents the first use of hiPSCs to model the effects of spaceflight on human cardiomyocyte structure and function.

This study investigated the interplay between the microbial community of the International Space Station and its crew. Environmental samples were collected from 8 habitable locations around the ISS. The microbial composition was measured using shotgun metagenomic sequencing and procesed using the Livermore Metagenomics Analysis Toolkit.

Using a novel flood source construct we performed a direct comparison of genome-wide gene expression regulations resulting from exposure of primary human prostate fibroblast cultures to acute (10cGy and 200cGy) and longer-term chronic (1.0-2.45cGy cumulative over 24hr) exposures.

Bone loss and immune dysregulation are among the main adverse outcomes of spaceflight challenging astronaut xe2 x80 x99s health and safety. However consequences on B cell development and responses are still under-investigated. Up to now most studies addressing these questions were performed using an amphibian species. Consequently we used advanced proteomics analysis of femur bone and marrow of mice flown for one month on board the BION-M1 biosatellite to determine whether extreme conditions encountered during a real spaceflight affect B cell development in mice and to examine reversibility of the effects upon return to Earth. Our data revealed that adverse effects on B lymphopoiesis were more marked one week after landing and that this phenomenon was associated with a 41% reduction of B cells in the spleen. Thus the effects of spaceflight persisted during at least one week after landing. These reductions may contribute to explain increased susceptibility to infection even if we confirmed that animals were able to mount a humoral immune response.

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.

We examined molecular responses using transcriptome profiling in isolated left ventricular murine cardiomyocytes to 90 cGy 1 GeV proton (1H) and 15 cGy 1 GeV/nucleon (n) iron (56Fe) particles 1 3 7 14 and 28 days after exposure. Unsupervised clustering analysis of gene expression segregated samples according to the radiation (IR) response and time after exposure with 56Fe-IR showing the greatest level of gene modulation. 1H-IR exposures showed little differential transcript modulation. Network analysis categorized the major differentially expressed genes into cell cycle oxidative responses and transcriptional regulation functional groups. Transcriptional networks identified key nodes regulating expression. Individual transcription factors were inferred to be active at 1 3 7 14 and 28 days after exposure. Validation of the signal transduction network by protein analysis showed that particle IR clearly regulates a long lived signaling mechanism for p38 MAPK signaling and NFATc4 activation. Electrophoresis mobility shift assays supported the role of additional key transcription factors GATA-4 STAT-3 and NF-kB as regulators of the response at specific time points. These data suggest that the molecular response to 56Fe-IR is unique and shows long-lasting gene expression in cardiomyocytes up to 28 days after exposure. Additionally proteins involved in signal transduction and transcriptional activation via DNA binding play a role in the response to high charge (Z) and energy (E) particles (HZE). Our study may have implications for NASA s efforts to develop heart disease risk estimates for astronauts safety via identification of specific HZE-IR molecular markers and for patients receiving conventional and particle radiotherapy. Transcriptome profiling in isolated left ventricular murine cardiomyocytes to 90 cGy 1 GeV proton (1H) and 15 cGy 1 GeV/nucleon (n) iron (56Fe) particles 1 3 7 14 and 28 days after exposure.

We examined molecular responses using transcriptome profiling in isolated left ventricular murine cardiomyocytes to 90 cGy 1 GeV proton (1H) and 15 cGy 1 GeV/nucleon (n) proton (56Fe) particles 1 3 7 14 and 28 days after exposure. Unsupervised clustering analysis of gene expression segregated samples according to the radiation (IR) response and time after exposure with 56Fe-IR showing the greatest level of gene modulation. 1H-IR exposures showed little differential transcript modulation. Network analysis categorized the major differentially expressed genes into cell cycle oxidative responses and transcriptional regulation functional groups. Transcriptional networks identified key nodes regulating expression. Individual transcription factors were inferred to be active at 1 3 7 14 and 28 days after exposure. Validation of the signal transduction network by protein analysis showed that particle IR clearly regulates a long lived signaling mechanism for p38 MAPK signaling and NFATc4 activation. Electrophoresis mobility shift assays supported the role of additional key transcription factors GATA-4 STAT-3 and NF-kB as regulators of the response at specific time points. These data suggest that the molecular response to 56Fe-IR is unique and shows long-lasting gene expression in cardiomyocytes up to 28 days after exposure. Additionally proteins involved in signal transduction and transcriptional activation via DNA binding play a role in the response to high charge (Z) and energy (E) particles (HZE). Our study may have implications for NASA s efforts to develop heart disease risk estimates for astronauts safety via identification of specific HZE-IR molecular markers and for patients receiving conventional and particle radiotherapy. Transcriptome profiling in isolated left ventricular murine cardiomyocytes to 90 cGy 1 GeV proton (1H) and 15 cGy 1 GeV/nucleon (n) proton (56Fe) particles 1 3 7 14 and 28 days after exposure.

Airborne microorganisms in the upper troposphere and lower stratosphere remain elusive due to a lack of reliable sample collection systems. To address this problem we designed installed and flight-validated a novel Aircraft Bioaerosol Collector (ABC) for NASA s C-20A that can make collections for microbiological research investigations up to altitudes of 13.7 km. Herein we report results from the first set of science flights xe2 x80 x94four consecutive missions flown over the United States (US) from 30 October to 2 November 2017. To ascertain how the concentration of airborne bacteria changed across the tropopause we collected air during aircraft Ascent/Descent (0.3 to 11 km) as well as sustained Cruise altitudes in the lower stratosphere (~12 km). Bioaerosols were captured on DNA-treated gelatinous filters inside a cascade air sampler then analyzed with molecular and culture-based characterization. Several viable bacterial isolates were recovered from flight altitudes including Bacillus sp. Micrococcus sp. Arthrobacter sp. and Staphylococcus sp. from Cruise samples and Brachybacterium sp. from Ascent/Descent samples. Using 16S V4 sequencing methods for a culture-independent analysis of bacteria the average number of total OTUs was 305 for Cruise samples and 276 for Ascent/Descent samples. Some taxa were more abundant in the flight samples than the ground samples including OTUs from families Lachnospiraceae Ruminococcaceae and Erysipelotrichaceae as well as the following genera: Clostridium Mogibacterium Corynebacterium Bacteroides Prevotella Pseudomonas and Parabacteroides. Surprisingly our results revealed a homogeneous distribution of bacteria in the atmosphere up to 12 km. The observation could be due to atmospheric conditions producing similar background aerosols across the western US as suggested by modeled back trajectories and satellite measurements. However the influence of aircraft-associated bacterial contaminants could not be fully eliminated and that background signal was reported throughout our dataset. Considering the tremendous engineering challenge of collecting biomass at extreme altitudes where contamination from flight hardware remains an ever-present issue we note the utility of using the stratosphere as a proving ground for planned life detection missions across the solar system.

The MARS500 project the longest ground-based space simulation ever provided us with a unique opportunity to trace the crew microbiota over 520 days of isolated confinement such as that faced by astronauts in real long-term interplanetary space flights and after returning to regular life for a total of 2 years.

This is a genome-wide approach to identifying genes persistently induced in the mouse mammary gland by acute whole body low dose ionizing radiation (10cGy) 1 and 4 weeks after exposure. Gene expression that is modified under these parameters were compared between Tgfb1 wild type and heterozygote littermates in order to determine which genes induced or repressed by radiation were mediated via Tgfb1 status. Differential gene expression was analyzed in Tgfb1 heterozygote and wild type littermate 4th mammary glands after whole body exposure to an acute dose of 10cGy ionizing radiation. Estrus cycle was normalized in all mice two days prior to irradiation by injection with an estrogen and progesterone mixture. It is widely believed that the carcinogenic action of ionizing radiation is due to targeted DNA damage and resulting mutations but there is also substantial evidence that non-targeted radiation effects alter epithelial phenotype and the stromal microenvironment. Activation of transforming growth factor beta 1 (TGFbeta) is a non-targeted radiation effect that mediates cell fate decisions following DNA damage and regulates microenvironment composition; it could either suppress or promote cancer. Gene expression profiling shown herein demonstrates that low dose radiation (10 cGy) elicits persistent changes in Tgfb1 wild type and heterozygote murine mammary gland that are highly modulated by TGFbeta. We asked if such non-targeted radiation effects contribute to carcinogenesis by using a novel radiation chimera model. Unirradiated Trp53 null mammary epithelium was transplanted to the mammary stroma of mice previously exposed to a single low (10 -100 cGy) radiation dose. By 300 days 100% of transplants in irradiated hosts at either 10 or 100 cGy had developed Trp53 null breast carcinomas compared to 54% in unirradiated hosts. Tumor growth rate was also increased by high but not low dose host irradiation. In contrast irradiation of Tgfb1 heterozygote mice prior to transplantation failed to decrease tumor latency or increase growth rate at any dose. Host irradiation significantly reduced the latency of invasive ductal carcinoma compared to spindle cell carcinoma as well as those tumors negative for smooth muscle actin in wild type but not Tgfb1 heterozygote mice. However irradiation of either host genotype significantly increased the frequency of estrogen receptor negative tumors. These data demonstrate two concepts critical to understanding radiation risks. First non-targeted radiation effects can significantly promote the frequency and alter the features of epithelial cancer. Second radiation-induced TGFbeta activity is a key mechanism of tumor promotion. Keywords: Differential gene expression after low dose irradiation Two genotypes: TGBbeta1 heterozygote and wildtype mouse mammary glands. Two time points post-10cGy-irradiation per genotype (1 week 4 weeks); control time point was 1 week post-sham-irradiation. Two or three replicates per time point.