Microbial-induced corrosion (MIC) severely threatens the structural integrity of metals in high-stakes environments, from aerospace to terrestrial infrastructure. Rapid, reliable detection is essential for informed mitigation and maintenance. The paper presents a computer-vision pipeline that establishes a new benchmark for MIC region segmentation in scanning electron microscopy (SEM) imagery. Central to this advancement is our expanded, expertly annotated dataset of 331 SEM images of MIC on stainless steel, the largest and, to our knowledge, first AI-ready segmentation dataset to include spaceflight samples to date. Leveraging this resource, we rigorously benchmark both classical and deep learning methods and introduce two deep learning architectures: an enhanced SAM2 and a novel Prompt- and Heatmap-Guided FPN-based Lightweight Segmentation Model (Lightweight PH-FPNSeg). Among these contributions, the most significant is the release of the curated, AI-ready MIC-SEM dataset with spaceflight samples, which we position as a reference benchmark for future work. The enhanced SAM2 and Lightweight PH-FPNSeg provide strong baselines on this benchmark. Both models deliver state-of-the-art results, achieving average Dice and IoU scores of 82% and 70%, respectively—substantially surpassing prior approaches.
Biofilms represent a common mode of bacterial growth, including the water recovery system (WRS) in spacecraft. Several factors have been associated with biofilm structure, including shear forces, microbial community composition, and available nutrients and other culture conditions. During an investigation of biofilm formation of a mixed cystitis isolate, Escherichia coli F11-mCherry and Pseudomonas aeruginosa PAO1-gfp culture during spaceflight in BioCellTM flight hardware with an artificial urine medium, we observed the gas-permeable Teflon (Tf) covering to become heavily colonized after 4 d by a P. aeruginosa-dominated biofilm that took on a structure resembling Van Gogh’s Starry Night. In contrast, Tf-adherent biofilms on the corresponding ground control exhibited no obvious clumping. The underlying stainless steel (SS)-adherent biofilms exhibited no obvious differences in morphology. Biofilm populations on both Tf and SS decreased and the morphology became more uniform at later time points (14 d and 117 d). In most cases, biofilms were more prominent in spaceflight samples than corresponding ground controls. E. coli was observed primarily at the early (4 d) time point, however P. aeruginosa, also associated with cystitis, was predominant at all time points. At 117-d, colonization was greatly reduced to a small number of P. aeruginosa, many of which became elongated on SS. Based on our results and similar findings by other investigators, we propose that microgravity conditions represent a factor that can influence biofilm formation, structure and their bacterial populations.
The inevitable introduction of human-associated microbes on Mars poses significant planetary protection risks, yet the survival potential of non-extremophiles under surface conditions remains ill-defined. We evaluated the resilience of three common gut bacteria—Enterococcus faecalis, Serratia liquefaciens, and Escherichia coli—under simulated Martian stressors including low pressure, CO₂-rich atmosphere, and perchlorate exposure, applied individually and in combination. Growth assays revealed a distinct tolerance hierarchy, with E. faecalis exhibiting the highest robustness, followed by E. coli and S. liquefaciens. Notably, combined stressors produced predominantly antagonistic effects across all three strains, indicating interactions that single-stressor assays may fail to capture. Transcriptomic profiling of E. faecalis under combined stress revealed a coordinated adaptive response involving conserved stress-response mechanisms rather than lineage-specific innovations. A concurrent potential shift toward enhanced surface adhesion and efflux activity, alongside suppression of acute virulence factors, raises biosafety concerns for crewed missions. Collectively, these results support a continuum model of microbial stress tolerance, in which persistence under extraterrestrial conditions does not require specialized extremophilic traits but can emerge from dynamic regulation of conserved systems, broadening the range of microorganisms relevant to forward-contamination risk.
NASA has a robust history of biomedical investigations using rodent models in spaceflight. The results from these experiments have provided significant insights into the effects of spaceflight on mammalian physiological systems for fundamental, biomedical and commercial research interests. To date, more than 19 long-duration (> 30-day) Rodent Research (RR) missions have been successfully conducted on board ISS using the NASA Rodent Habitat. Recent installation of digital cameras within the Rodent Habitat to support in-flight video observations can provide recordings during spaceflight. We hypothesized that application of unique fur dye patterns would enable individual identification of animals and small, implantable data loggers could be used to collect and store body temperature data. We designed and performed two ground-based validation studies. First, animals were housed in the Rodent Habitat in groups of five; fur dye markings enabled identification of individual mice. Body temperature was acquired using implanted dataloggers. Video was recorded and species typical behaviors were quantified for individual mice during both light and dark phases. Second, centrifugation was used to mimic launch. For the first time, we validated the biocompatibility of datalogger implants, fur dye pattern application and mouse visual identification methods using digital video and behavioral analysis protocols.
The detection of extracellular mitochondrial DNA (ex-mtDNA) and extracellular mitochondria (ex-Mito) in astronauts’ blood during space missions raises intriguing questions about their potential roles in human health under the unique stressors of spaceflight. However, current methods for detecting ex-mtDNA and ex-Mito in blood samples collected before, during, and after spaceflight fail to provide a clear understanding of their characteristics. ex-mtDNA may exist in various forms, such as encapsulated within ex-Mito or completely membrane-free, and the methods of sample collection and handling are critical for accurate analysis. Despite its potential significance, the origins, properties, and health implications of ex-mtDNA and ex-Mito remain largely unexplored in the context of terrestrial and space medicine. This perspective article aims to consolidate existing knowledge, evaluate methodologies for their identification and analysis, and offer critical insights into the biological significance of ex-mtDNA and ex-Mito. By integrating findings from Earth-based studies with the challenges of space exploration, this article seeks to advance our understanding of these novel blood components, laying the groundwork for innovative research in space medicine and strategies to safeguard astronaut health during extended space missions.
As long-term human spaceflight becomes increasingly feasible, understanding the biological effects of the space environment on the human body has become ever more important. Among the environmental factors that distinguish space from Earth, microgravity and space radiation have been reported to exert diverse effects on the central nervous system, including signs of accelerated aging, structural alterations of the brain, and cognitive impairment. Because the brain is a highly complex organ with region-specific functions and metabolic characteristics, it is essential to investigate brain region–specific responses to spaceflight. Open Science Datasets provided by NASA GeneLab (OSD-682, 685, 698, and 699) provide transcriptomic profiles from four anatomically distinct brain regions following 35 days of spaceflight, with and without antioxidant treatment. Previous studies and related datasets have demonstrated that spaceflight induces oxidative stress and mitochondrial damage in the brain. Although such conditions are compatible with molecular features associated with ferroptosis, an iron-dependent form of programmed cell death described relatively recently, the relationship between spaceflight and ferroptosis in the brain has not yet been systematically examined. In this study, we analyzed region-resolved transcriptomic profiles to show at the pathway level that long-term spaceflight is associated with selective ferroptosis-related transcriptional signatures in the hippocampus, particularly within the dentate gyrus. We further suggest that iron dysregulation and increased reactive oxygen species may contribute to these transcriptional alterations. In addition, the observed association between ferroptosis-related pathways and the enrichment of neurodegenerative disease–related pathways in the dentate gyrus supports the notion that ferroptosis may represent a potential molecular mechanism contributing to spaceflight-induced neurodegenerative alterations.
Dry immersion (DI) serves as a validated analogue for microgravity, yet transcriptomic responses in women have been scarcely studied. Here, we present a TP53-focused transcriptomics re-analysis of female participants following 5 days of DI, highlighting TP53-related stress responses relevant to astronaut health. RNA-seq data were generated from blood samples collected from 18 healthy women at baseline (BDC-1), day 2 (DI2), day 5 (DI5), and post-recovery (R + 1). Differential gene expression and pathway enrichment analyses assessed timepoint-specific transcriptional changes, with emphasis on TP53 regulation. Principal component analysis showed timepoint-dependent divergence, with the most significant alterations occurring at DI5 and a partial reversion by R + 1. TP53 targets linked to DNA repair (GADD45A, DDB2), oxidative defence (SESN1, TP53I3), and apoptosis (BAX, BBC3) were upregulated during immersion. Pathway responses included activation of hypoxia and interferon signalling, and suppression of haem metabolism and coagulation. Together, these findings provide insight into female molecular adaptation to short-term unloading, highlighting a swift yet reversible TP53 response accompanied by immune, metabolic, and vascular adaptations. These observations advance our understanding of the molecular mechanisms underlying women’s physiological responses to unloading and support the development of sex-informed precision health strategies for future space missions.
As crewed long-duration space exploration missions become increasingly Earth-independent and reliant on onboard technology, risks due to human-system incompatibility become critical to address. In a space habitat, establishing objective and meaningful relationships between the individual and the environment has been challenging due to multidirectional influences between system components. Feedback loops between behavioral health processes and outcomes complicate characterization of influence within the system. Yet, it remains crucial for habitat designers and stakeholders to trade design decisions and their associated risks. In this work, we have created a risk mapping of the impact of habitat design to behavioral health and performance outcomes in isolated, confined, and extreme environments. We leverage a Directed Acyclic Graph (DAG) to formalize habitat design parameters as powerful mediators between mission stressors and behavioral health outcomes. To represent the DAG accessibly, we created the Human-Environment Connection & Interaction Atlas ( https://hecia.space ), an interactive open-source platform. We conducted expert and user interviews to evaluate the underlying DAG and the usability of the tool. Herein, we present our novel development of a risk map that links habitat design and behavioral health, as well as an interactive visualization that can provide a basis for accessible communication of complex systems.
Mesenchymal stem cells (MSCs) hold broad therapeutic potential, yet the absence of validated, scalable adherent culture methods remains a barrier to orbital biomanufacturing. Here, we report the first integrated workflow for MSC culture on pre-seeded microcarriers (µCs) encompassing cryopreservation, ambient thaw, and expansion aboard the International Space Station. We engineered heparan sulfate-collagen (HS/COL) µCs with defined sulfation levels to modulate integrin engagement and factor-release kinetics and benchmarked them against commercial µCs and suspension controls. Our results demonstrate that pre-seeded MSCs remain viable and adherent throughout the spaceflight lifecycle, with ambient workflows enabling parallel evaluation of multiple donors and surface chemistries while minimizing crew intervention. In microgravity, MSC proliferation peaked 3 days earlier than on Earth, with highest cell yields being obtained with low-sulfated HS/COL µCs. Secretome analyses revealed increased pro-collagen and extracellular vesicle release with preserved bioactive microRNA cargo. While HS/COL surfaces buffered microRNA homeostasis, suspension and commercial µC cultures exhibited orbit-specific miRNA signatures associated with cytoskeletal remodeling and immune regulation. Post-flight, MSCs recovered from µCs retained proliferative capacity and multipotency, though microgravity exposure favored adipogenic over chondrogenic differentiation. Collectively, these results establish a scalable culture strategy using pre-seeded µCs for stem cell research and biomanufacturing in space.
Boundary cap neural crest stem cells (BCs) previously demonstrated resilience during short-term microgravity exposure. In this study, BCs were sent to the International Space Station aboard Axiom Mission 3. Owing to launch regulations and weather delays, cells remained outside controlled culture conditions longer than anticipated, exceeding expected survival limits. Three BC populations were included: naive BCs (NBC), once-flown BCs (V15), and twice-flown BCs (V1415), cultured as neurospheres or within 3D-printed scaffolds. Corresponding ground controls were maintained under matched conditions. Only V1415 cells survived in both flight and ground groups, while NBC cells survived exclusively after spaceflight. V15 cells did not survive. All surviving cells exhibited reduced proliferation, contrasting with the enhanced proliferation reported after short-term microgravity exposure. Following 1 month of post-flight expansion, surviving cells retained the capacity to differentiate into neurons and glial cells without detectable electrophysiological impairment. Space-exposed NBC cultures showed increased glial differentiation, whereas V1415 flight cultures displayed a higher neuronal proportion than ground controls. BCs cultured in 3D-printed scaffolds exhibited robust survival and significantly increased proliferation after space exposure. Exosome analysis identified miRNAs associated with enhanced proliferation in flight samples. These findings demonstrate the remarkable stress resistance, developmental plasticity, and adaptability of BCs during prolonged spaceflight conditions.
Human-rated suborbital vehicles present the opportunity to conduct science during the transitions to space and back. This opportunity is enhanced by the ability to include researchers in the crew who can conduct real-time experiments in what is effectively a shirt-sleeve environment. While numerous suborbital flights have carried autonomous research payloads, suborbital vehicle systems have yet to be fully operationalized as platforms for scientists to physically conduct experiments. Therefore the present study was designed as an early step to advance this operationalization through a researcher-tended experiment on New Shepard flight NS-26, with the science objective to sample plant responses at four specific moments of the suborbital spaceflight experience – on the tower just before launch, after launch at capsule separation and entry into microgravity, just before reentry, and shortly after landing. The conduct of the experiment also further operationalized the use of Kennedy Space Center Fixation Tubes (KFTs) within suborbital flights by using duplicate KFTs to capture replicate samples preserved in RNAlater at each of the timepoints. Further, the replicated sampling during flight was precisely matched in real time with ground control sampling. This approach enabled a robust analysis of gene expression changes in Arabidopsis seedlings during the spaceflight experience. Rapid, specific reprogramming of the transcriptome occurred, especially during the boost and microgravity phases of the flight. Some of the differentially expressed genes were related to genes differentially regulated during longer-term orbital spaceflight; however, the nature of many of the metabolic pathways that were differentially regulated early in suborbital spaceflight suggests that entry into space produces a rapid, acute response involving misfolded proteins and other reactive oxygen species stresses—some of them involving mitochondrial processes.
This study employed a before-and-after design and utilized proton density fat fraction (PDFF) magnetic resonance imaging (MRI) to investigate the effects of 7 days of -6° head-down tilt bed rest (HDBR) on the lower limb muscles of healthy men. We performed multiple MRI scans of the participants’ thighs and calves during the HDBR period and collected blood and urine samples at corresponding time points to analyse biomarkers. We observed a sustained and significant reduction in thigh muscle cross-sectional area (TMCSA) and medial head of the gastrocnemius muscle cross-sectional area (MHMCSA) during HDBR (p < 0.001). The thigh subcutaneous adipose tissue area (TSAT) and the calf subcutaneous adipose tissue area (CSAT) showed a downward trend at the onset of HDBR, followed by a gradual recovery. During HDBR, both the thigh and calf muscle contractile mass index (CMI) exhibited a significant and sustained downward trend. Phosphorus (P), direct renin (DR), and red blood cells (RBC) showed significant correlations with muscle/fat parameters (p < 0.05). Our findings indicate that short-term HDBR leads to lower limb muscle atrophy and subcutaneous fat redistribution, and that these changes are dynamically associated with stress responses, metabolic indicators, and biomarkers related to bone metabolism.
The hippocampus is a particularly plastic and vulnerable brain structure. Given the modulatory role of the vestibular system on hippocampal function, we hypothesized that altered vestibular stimulation associated with prolonged spaceflight could lead to similar hippocampal volume changes in astronauts after long-duration spaceflight and in individuals with bilateral vestibulopathy (BV), as a ground analog of spaceflight. We quantified hippocampal volumes using magnetic resonance imaging (MRI) in astronauts before and after spaceflight and in BV patients relative to matched healthy controls. MRI analyses revealed a significant decrease in the left hippocampal volume (-2%) and an increase in the total volume of the ventricles (+11%) postflight in astronauts. The variations in volume of right and left hippocampus and ventricles were not correlated with each other, suggesting that the cerebrospinal fluid redistribution that occurs with spaceflight does not contribute to hippocampal volume changes. BV patients exhibited reduced hippocampal volumes compared to matched controls (-6% left and -4% right), suggesting that reduction of vestibular inputs, due either to microgravity or a disease, may contribute to hippocampal atrophy. Furthermore, in both astronauts and BV patients, hippocampal volume correlated negatively with age, suggesting increased vulnerability of older individuals to vestibular-related neurodegeneration. Overall, our findings suggest that hippocampal atrophy in astronauts is not driven by mechanical compression, due to CSF redistribution but it may be affected by reduced vestibular input, aligning with observations in terrestrial vestibular loss.
Spaceflight studies in humans show that microgravity alters the gut microbiome, posing a risk to health. Understanding how microbiomes and host genetics influence physiology is critical for long-duration missions. The low-cost spaceflight model C. elegans provides a suitable means to study host-microbiome interactions. However, whole-organism measurements are limited by lacking suitable flight-ready hardware that enables long-term nematode culture compatible with on-orbit imaging. These limitations were addressed through development of NemaCapsules— microfluidics-integrated biocells, for spaceflight assessment of C. elegans locomotion under defined microbiome conditions, with minimal astronaut workload. This provided a fully sealed, gas-permeable system with media reservoir, enabling passive, long-term nematode culturing. NemaCapsules were evaluated across four host strains and three model microbiomes. Multi-day worm viability studies demonstrated high resilience across diverse host strains and microbiomes except for daf-16 mutants. Crawling and swimming studies of worms with model microbiomes of C. elegans natural microbiota exhibited distinct locomotory activity from those exposed to E. coli OP50. Wild-type N2 generally exhibited the highest activity, followed by wild isolate strains; daf-16 mutants demonstrated lowest activity. Compared to crawling, swimming better revealed differences arising from host-microbiome interactions. NemaCapsules provide a modular solution for on-orbit, multi-functional readouts in C. elegans with minimal crew intervention.
Spaceflight-induced immune system dysregulation coupled with limited clinical care represents a risk for crew members. This study aimed to discern which stressor encountered during a space mission impact the antibody repertoire. Via next-generation sequencing, we analyzed the immunoglobulin heavy chain repertoire of volunteers wintering for a year in Antarctica at two stations, Neumayer III (sea level) and Concordia (altitude of 3233 m), which are recognized ground-based analogs of the space environment except for the gravity change and radiation. Our results showed that, as in space crewmembers, 40% of individuals at both stations developed significant changes in their antibody repertoire during polar night. Furthermore, similar to cosmonauts, these modifications were associated with a modification of the V(D)J recombination process responsible for creating antibody genes. These results suggest that physical and socioenvironmental stressors alone can contribute to antibody repertoire changes, confirming the need to implement operational improvements and personalized approaches during future deep-space exploration missions.
This study investigated the long-term neurobehavioral and physiological impacts of low-dose helium (4He) ion exposure-a key component of galactic cosmic radiation-on male Long Evans rats. After training on the rodent psychomotor vigilance test (rPVT), the rats were irradiated and monitored for up to 180 days to assess sustained attention and social recognition memory, alongside blood and bone analyses. Results showed that acute exposure to 25 cGy 4He ions significantly impaired sustained attention, increasing attention lapses and reaction times, and decreasing task accuracy. Exposure to 5 cGy only affected specific reaction time measures. However, both doses caused persistent social recognition memory impairments for 180 days. While overall bone mechanics remained largely unchanged, specific skeletal strength parameters were affected. Importantly, significant correlations emerged between behavioral performance and circulating cytokines (IL-1beta), undercarboxylated osteocalcin (ucOC), and bone biomechanics. This suggests these blood and bone targets could serve as diagnostic biomarkers for radiation-induced neurobehavioral deficits. The sustained and progressive nature of the neurobehavioral deficits observed underscores the critical need for effective countermeasures to protect astronaut health and performance during exploration-class missions.
Humans will return to the Moon and travel to deep space on their journey to Mars. Space exploration presents significant hazards to human health, including exposure to ionizing radiation (IR) from galactic cosmic rays (GCR) and solar particle events (SPEs). Space radiation-induced carcinogenesis is considered a primary risk to astronaut health. However, cardiovascular disease (CVD) and central nervous system (CNS) dysfunction have emerged as significant health risks for astronauts. Small animal models, particularly rodents, have provided valuable information regarding IR effects on the cardiovascular and CNSs; however, these small animal models have limitations in mimicking human metabolism and physiology, highlighting the need for alternative models. Minipigs are highly translational cardiovascular and neurovascular models due to their close similarities to humans in anatomy, physiology, metabolism, and immune responses. Their use enables clinically relevant assessment of space radiation-induced cardiovascular and neurological effects. This review highlights the advantages and limitations of minipigs as radiation models, including their utility for investigating sex-specific responses and their integration with emerging microphysiological systems. Together, these approaches provide a translational platform for mechanistic discovery, biomarker identification, risk assessment, and the development of countermeasures to protect astronaut health during future deep-space missions.
Space exploration is important for scientific discovery, advancing technology, and the long-term survival of humanity. However, the impacts of microgravity and cosmic radiation during space travel on human physiology are not completely understood. While microgravity results in a loss of skeletal muscle mass and function, the effect on cardiac muscle, in particular the contractile elements, is not as clear. Here, we examine the effect of spaceflight on the myocardial contractile function of skinned cardiomyocytes from mice that traveled to the International Space Station (spaceflight, N = 5) and age-matched ground controls (ground control, N = 5, and vivarium, N = 3). These experiments allow for the characterization of the mechanical properties of the sarcomere, the fundamental unit of contraction. The functional experiments showed that ~38.5 days in space does not alter force-generating capacity (Tmax), calcium sensitivity (EC50), and cooperativity of the sarcomere. The passive force and cross-sectional area (CSA) were the same between the spaceflight and ground control groups. We next performed mass spectrometry (MS) analysis, and gene ontology analysis confirmed that pathways associated with sarcomere contractility remained unchanged. However, the MS data showed that the spaceflight group exhibited immune‑related proteomic changes compared to the ground controls. Together, these results suggest that ~38.5 days of space travel does not substantially affect the intrinsic contractile state of murine cardiomyocytes.
Gravity is a fundamental environmental factor influencing plant evolution and development. As humanity prepares for long-duration space missions, understanding plant responses to microgravity is crucial for sustainable space agriculture. While the International Space Station (ISS) offers an ideal research environment, high costs and limited accessibility have necessitated the use of ground-based microgravity simulators, such as 2D and 3D clinostats and Random Positioning Machines (RPM). This review summarizes the physical principles of these devices and synthesizes plant biological responses, including organ-level morphogenesis, cellular structure, hormonal balance, and molecular metabolism. We critically compare ground-based simulation data with actual spaceflight results, identifying areas of high reproducibility-such as statolith randomization and automorphogenesis-as well as significant discrepancies that might be caused by simulator-specific artifacts like mechanical vibration, centrifugal acceleration, and fluid shear stress. Furthermore, we emphasize the need for standardized performance metrics, including time-averaged simulated microgravity (taSMG) and the degree of gravity dispersion (DGD), to enhance data reliability. Finally, we discuss how technical innovations such as brushless direct current (BLDC) motor integration and 3D printing can bridge the “space-ground gap”. This review provides a strategic framework for optimizing ground-based research to support the development of life support systems for future lunar and Martian habitats.
