Traveling to nearby extraterrestrial objects having a reduced gravity level (partial gravity) compared to Earth's gravity is becoming a realistic objective for space agencies. The use of plants as part of life support systems will require a better understanding of the interactions among plant growth responses including tropisms, under partial gravity conditions. Here, we present results from our latest space experiments on the ISS, in which seeds of Arabidopsis thaliana were germinated, and seedlings grew for six days under different gravity levels, namely micro-g, several intermediate partial-g levels, and 1g, and were subjected to irradiation with blue light for the last 48 hours. RNA was extracted from 20 samples for subsequent RNAseq analysis. Transcriptomic analysis was performed using the HISAT2-Stringtie-DESeq pipeline. Differentially expressed genes were further characterized for global responses using the GEDI tool, gene networks and for Gene Ontology (GO) enrichment.

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 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 purpose of this study was to evaluate transcriptional changes in mouse spleens using a ground-based model for spaceflight. This model includes prolonged unloading and low-dose irradiation. Low-dose-rate gamma-radiation was delivered to 6-month old female C57BL/6J mice using 57Co plates (0.04 Gy) to simulate the radiation environment of spaceflight. Anti-orthostatic tail suspension was used to model the unloading fluid shift and physiological stress aspects of the microgravity component of spaceflight. Mice were hindlimb suspended and/or irradiated for 21 days. Mice were euthanized and spleens collected 7 days following treatment. RNA sequencing data was generated to assess transcriptional changes in these spleens.

Among the physiological consequences of extended spaceflight are loss of skeletal muscle and bone mass. One signaling pathway that plays an important role in maintaining muscle and bone homeostasis is that regulated by the secreted signaling proteins myostatin (MSTN) and activin A. Here we used both genetic and pharmacological approaches to investigate the effect of targeting MSTN/activin A signaling in mice that were sent to the International Space Station. Wild type mice lost significant muscle and bone mass during the 33 d spent in microgravity. Muscle weights of Mstn -/- mice which are about twice those of wild type mice were largely maintained during spaceflight. Systemic inhibition of MSTN/activin A signaling using a soluble form of the activin type IIB receptor (ACVR2B) which can bind each of these ligands led to dramatic increases in both muscle and bone mass with effects being comparable in ground and flight mice. Exposure to microgravity and treatment with the soluble receptor each led to alterations in numerous signaling pathways which were reflected in changes in levels of key signaling components in the blood as well as their RNA expression levels in muscle and bone. These findings have implications for therapeutic strategies to combat the concomitant muscle and bone loss occurring in people afflicted with disuse atrophy on Earth as well as in astronauts in space especially during prolonged missions.

Adult and neonatal human cardiovacular progenitor cell clonal populations were flown aboard the ISS for 12 days prior to fixation in RNAprotect. Gene expression analysis was performed against clone- patient- and passage-matched ground control samples. qPCR gene expression profiling. Human CPCs from three neonates and three adults were individually cultured on the ground or aboard the ISS.

Gene expression changes induced by acute skeletal muscle unloading which leads to physiological changes including muscle atrophy fibre-type switching and loss of ability to transition between lipid and glucose as energy source (metabolic inflexibility) was investigated by hind-limb suspension (HLS) treatment of Male ICR mice (28 x9632 g body wt; Harlan Indianapolis IN). Agilent Whole Mouse Genome Oligo Microarrays were utilised to examine the effects of HLS on mRNA expression profiles of the soleus muscle and the gastrocnemius muscle in the hindlimbs of freely ambulating control and 24h HLS treated mice.

The objective of the Rodent Research-6 (RR-6) study was to evaluate muscle atrophy in mice during spaceflight and to test the efficacy of a novel therapeutic to mitigate muscle wasting. The experiment involved an implantable subcutaneous nanochannel delivery system (nDS; between scapula) which delivered the drug formoterol (FMT; a selective xce xb22 adrenoceptor agonist) over the course of time. To this end a cohort of forty 32-weeks-old female C57BL/6NTac mice were either sham operated or implanted with vehicle or treatment-filled nDS launched in two Transporters (20 mice per Transporter) on SpaceX-13 on December 15 2017. They were transferred to Rodent Habitats onboard the International Space Station (ISS) and maintained in microgravity for 29 days (N=20 Live Animal Return Spaceflight [LAR FLT]) or >50 days (N=20 ISS Terminal Spaceflight [ISS-T FLT]). After 29 days the 20 LAR FLT animals were returned live to back to Earth on January 13 2018. After splashdown the animals were ambulatory on-ground for ~4 days until all subjects were processed during one day of dissections. There were two Basal (BSL) groups of animals sacrificed (LAR BSL & ISS-T BSL; N=20; 40 animals; ~36 weeks old) at Kennedy Space Center (KSC; 12/9/17). LAR BSL animals were dissected and samples were collected upon euthanasia. A Ground Control (GC) group LAR GC mimicked the LAR FLT group which was housed at KSC then shipped alive to Novartis xe2 x80 x99s Facilities where both the LAR FLT and LAR GC groups were processed (~41 weeks old; 1/16/18). All were anesthetized with isoflurane blood samples were obtained by closed-chest cardiac puncture and the animals were euthanized by exsanguination and thoracotomy. The 20 ISS-T FLT mice were anesthetized via intraperitoneal injection of ketamine/xylazine/acepromazine over the course of a four days of dissections (2/6/18 until 2/9/18; 53-56 days after launch; 44 weeks old at time of on-orbit dissections). Blood samples and euthanasia were conducted the same as LAR groups. Following blood draw and hind limb dissection the ISS-T FLT animal carcasses were wrapped in aluminum foil placed in a ziploc bag and placed in storage at -80 xcb x9aC or colder until return. The ISS-T Ground Control (ISS-T GC) (at KSC) followed the same euthanasia timeline methods and preservation. The final processing of frozen ISS-T FLT frozen ISS-T GC and frozen 0-day ISS-T BSL animals were completed at Houston Methodist Research Institute in Houston TX (5/21/18 until 5/24/18). GeneLab received feces from only sham treated animals (no drug treated animals) from the following groups. FLT: LAR (n=9) ISS-T (n=7); GC: LAR (N=7) ISS-T (N=9); BSL: LAR (n=7) ISS-T (n=9). DNA was extracted and analyzed by sequencing using a variety of different targeted and un-targeted metagenome profiling assays.

The purpose of this study was to evaluate transcriptional changes in mouse skin using a ground-based model for spaceflight. This model includes prolonged unloading and low-dose irradiation. Low-dose-rate gamma-radiation was delivered to 6-month old female C57BL/6J mice using 57Co plates (0.04 Gy) to simulate the radiation environment of spaceflight. Anti-orthostatic tail suspension was used to model the unloading fluid shift and physiological stress aspects of the microgravity component of spaceflight. Mice were hindlimb suspended and/or irradiated for 21 days. Mice were euthanized and dorsal skin was collected 7 days following treatment. RNA sequencing data was generated to assess transcriptional changes in these skin samples.

Bacillus pumilus SAFR-032 was originally isolated from the Jet Propulsion Lab Spacecraft Assembly Facility and thoroughly characterized for its enhanced resistance to UV irradiation and oxidative stress. This unusual resistance of SAFR-032 is of particular concern in the context of planetary protection and calls for development of novel disinfection techniques to prevent extraterrestrial contamination. Previously spores of SAFR-032 were exposed for 18 xe2 x80 x89months to a variety of space conditions on board the International Space Station to investigate their resistance to Mars-like conditions and space travel. Here proteomic characterization of vegetative SAFR-032 cells from space-surviving spores is presented in comparison to a ground control. Vegetative cells of the first passage were processed and subjected to quantitative proteomics using tandem mass tags. Approximately 60% of all proteins encoded by SAFR-032 were identified and 301 proteins were differentially expressed among the strains. We found that proteins predicted to be involved in carbohydrate transport/metabolism and energy production/conversion had lower abundance than those of the ground control. For three proteins we showed that the expected metabolic activities were decreased as expected with direct enzymatic assays. This was consistent with a decrease of ATP production in the space-surviving strains. The same space-surviving strains showed increased abundance of proteins related to survival growth advantage and stress response. Such alterations in the proteomes provide insights into possible molecular mechanisms of B. pumilus SAFR-032 to adapt to and resist extreme extraterrestrial environments.