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PubMed2026

Efficacy and safety of ferric citrate tablets in Chinese patients with hyperphosphatemia undergoing maintenance hemodialysis: a multicenter, randomized, open-label, active-controlled, phase III trial.

BACKGROUND: This study aimed to evaluate the efficacy and safety of ferric citrate tablets in Chinese patients with hyperphosphatemia undergoing maintenance hemodialysis (MHD). METHODS: In this phase III, multicenter, randomized, open-label, non-inferiority trial, patients with hyperphosphatemia on maintenance hemodialysis were randomly assigned to receive either ferric citrate or sevelamer carbonate tablets for 12 weeks. The primary endpoint was the change in serum phosphorus levels from baseline to week 12, with a non-inferiority margin of 0.32 mmol/L. Secondary endpoints included changes in serum calcium, intact parathyroid hormone, and safety assessments. RESULTS: A total of 239 patients were randomized to the ferric citrate group (n = 119) or the sevelamer carbonate group (n = 120). The mean change in serum phosphorus levels was -0.70 ± 0.50 mmol/L in the ferric citrate group and -0.61 ± 0.59 mmol/L in the sevelamer carbonate group (least squares mean difference, -0.09 mmol/L; 95% CI, -0.24 to 0.05 mmol/L; non-inferiority margin, 0.32 mmol/L). No significant inter-group differences were found in the percentage of patients achieving target phosphorus levels (49.09% vs. 48.28%, p = 0.902). Ferric citrate significantly improved iron-related parameters and hemoglobin levels. Most treatment-emergent adverse events were mild, with gastrointestinal disorders being the most common. CONCLUSIONS: Ferric citrate tablets were non-inferior to sevelamer carbonate in reducing serum phosphorus levels in hyperphosphatemia patients on maintenance hemodialysis, with the added benefit of improving iron-related anemia and a favorable safety profile.

Adult↗

PubMed2026

Post-trial 12-month follow-up of TRACE (targeted research on addictive and compulsive eating) randomised controlled trial participants: A brief report.

Few treatment interventions for addictive eating have evaluated long-term effectiveness. This post-trial follow-up study evaluates secondary changes in addictive eating symptoms and quality of life at 12-months in a sample of individuals who participated in the TRACE (Targeted Research for Addictive and Compulsive Eating) RCT. Thirty-three adults out of possible 144 (82% female), median age 53 years, randomised to either the active intervention (five telehealth sessions delivered over 3-months), passive intervention (self-guided workbook) or control group completed an online post-trial survey. Pre- and immediate post-intervention (3-months) outcomes were compared to 12-months post-trial outcomes. Positive effects reported in the short term showed a rebound effect at post-trial follow-up in ∼50% of participants. The findings suggest that longer term support is needed to maintain changes in addictive eating behaviours and improve quality of life. Future research is needed to identify optimal intervention durations and support options for sustained change. Australian New Zealand Clinical Trials Registry (ACTRN12621001079831).

Humans↗

PubMed2026

Tissue-derived extracellular matrix hydrogels instruct epigenetic adaptation in metastatic colonization.

The extracellular matrix (ECM) plays a central role in regulating tumor progression and metastatic colonization by providing biochemical and mechanical signals that shape cancer cell fate. However, most organoid culture systems rely on basement membrane extracts that fail to reproduce the tissue-specific extracellular environments encountered during metastasis. Here, we develop tissue-derived decellularized matrix hydrogels to reconstruct organ-specific microenvironments and investigate epigenetic adaptation to ECM cues during metastatic colonization. Patient-derived colorectal cancer organoids cultured in colon-derived matrices exhibited enhanced maintenance of stem-like phenotypes and colon-specific chromatin accessibility landscapes compared with cultures grown in basement membrane extracts, demonstrating improved physiological relevance for primary tumor modeling. When exposed to matrices derived from secondary organs, the organoids showed distinct growth phenotypes accompanied by rapid, tissue-dependent chromatin accessibility remodeling, indicating that ECM composition alone can reshape regulatory programs governing metastatic adaptation. Notably, liver-derived matrices selectively activated hepatocyte nuclear factor 4 alpha (HNF4A)-associated transcriptional networks and created a context-specific dependence on c-MET signaling for survival. Functional perturbation of HNF4A or c-MET signaling confirmed that both are required for organoid formation specifically within the liver matrix environment. Together, these findings establish tissue-derived matrix hydrogels as instructive bioactive materials that actively regulate cancer cell epigenetic states and reveal microenvironment-specific therapeutic vulnerabilities during early metastatic colonization.

Journal Article↗

PubMed2026

Proteomic responses of the oil palm pest Metisa plana (Psychidae) to farnesyl acetate exposure.

Metisa plana Walker (Lepidoptera: Psychidae) is a major defoliator of oil palm in Malaysia, causing substantial economic losses. Farnesyl acetate (FA), a sesquiterpenoid compound, has been proposed as a potential insecticidal agent against M. plana, yet its molecular impact on larval physiology remains poorly understood. Here, we employed label-free quantitative proteomics, functional enrichment analysis, and targeted transcript assessment to characterize the temporal proteomic response of M. plana larvae at 7 and 14 days after treatment (DAT) with FA. Principal component analysis revealed robust separation between treated and control samples at both time points, indicating sustained treatment-driven proteomic restructuring. Early exposure (7 DAT) elicited a heterogeneous response involving stress-associated proteins, redox enzymes, and cytoskeletal regulators, whereas later exposure (14 DAT) produced a consolidated profile characterized by metabolic reprogramming, downregulation of ribosomal proteins, induction of heat shock proteins, and enrichment of RNA surveillance and mitochondrial pathways. Targeted transcript analysis qualitatively supported proteomic trends for HSP83 and aldehyde dehydrogenase X, although limited amplification precluded quantitative inference. Collectively, these findings demonstrate that FA exposure drives a shift from acute proteomic perturbation toward a maintenance-oriented physiological state, prioritizing proteostasis, energy management, and stress adaptation over growth and development. This integrated molecular perspective provides mechanistic insight into the chronic effects of FA, highlighting its potential to suppress larval performance and informing the development of biorational, physiology-based pest management strategies in non-model insects.

Animals↗

PubMed2026

Transcriptome analysis of the pectoral fin degeneration in half-smooth tongue sole (Cynoglossus semilaevis).

Appendage degeneration is a notable morphological feature of some teleosts with specialized benthic lifestyles. The half-smooth tongue sole (Cynoglossus semilaevis) undergoes severe pectoral fin regression during metamorphosis. However, the molecular basis underlying rapid pectoral fin degeneration remains unclear. Here, we performed time-series transcriptome sequencing on pectoral fins at pre-metamorphosis, metamorphosis peak and post-metamorphosis to characterize the molecular changes associated with pectoral fin degeneration. Transcriptional dynamics and functional enrichment showed that no significant enrichment of classical apoptosis-related transcriptional pathways was detected during pectoral fin degeneration. Instead, sustained downregulation of twist1b, identified as a transcriptomic candidate, together with significant upregulation of ssh1, coupled with enrichment of lysosome and ubiquitin-proteasome system (UPS) pathways, suggested enhanced tissue remodeling during pectoral fin degeneration. Temporal expression clustering revealed heterochronic misalignment in the developmental gene expression: upstream initiator tbx5 was upregulated at early metamorphosis, while downstream maintenance signal fgf10 decreased synchronously. Distal patterning gene hoxd12a exhibited premature expression and rapid decay, losing sustained late-phase expression. Moreover, transient elevation of gli3 during metamorphosis may contribute to restricted distal fin growth. We conclude that pectoral fin degeneration in C. semilaevis is associated with heterochronic disruption of developmental signaling and extensive tissue remodeling. This study provides transcriptomic insights into pectoral fin degeneration in tongue soles and establishes a basis for future functional studies of appendage reduction in teleosts.

Animals↗

PubMed2026

Multi-omics analysis reveals stage-associated differences in gut immunity and microbiota between juvenile and adult common carp (Cyprinus carpio).

In vertebrates, the development of intestinal immunity is closely associated with dynamic changes in the gut microbiota. However, stage-associated differences in intestinal immunity and gut microbial communities remain poorly characterized in teleost fish. In this study, transcriptomic analysis combined with 16S rRNA gene sequencing was employed to characterize intestinal immunity and gut microbial communities in juvenile and adult common carp (Cyprinus carpio). Transcriptomic profiling revealed marked developmental differences in intestinal immune function. Juvenile carp exhibited a predominantly innate immune phenotype, characterized by elevated expression of pro-inflammatory cytokines, antimicrobial peptides, and lysozyme-related genes. This immune profile was accompanied by enhanced mucosal barrier function and a relatively pro-inflammatory intestinal environment. In contrast, adult carp displayed increased expression of genes associated with adaptive immunity, suggesting that adult common carp exhibit relatively stronger adaptive immune characteristics than juvenile fish. Gut microbiota analysis demonstrated significant stage-dependent differences in microbial diversity and community composition. Juvenile fish were enriched with bacterial taxa potentially associated with innate immune activation, whereas adult fish harbored distinct microbial communities linked to intestinal homeostasis and barrier maintenance. Furthermore, correlation analyses identified significant associations between specific microbial taxa and innate immune-related gene expression, suggesting a close association between gut microbiota composition and intestinal immune characteristics in juvenile and adult common carp. Collectively, these findings reveal stage-associated differences in intestinal immunity and gut microbial communities between juvenile and adult common carp, thereby providing insights into intestinal immune characteristics at different developmental stages in teleost fish.

Animals↗

PubMed2026

Natural products alleviate exercise-induced fatigue by modulating gut microbiota: a systematic review.

BACKGROUND: Exercise-induced fatigue critically impairs athletic performance and training quality. The gut microbiota, as a key regulator of the "gut-muscle axis," has emerged as a promising anti-fatigue target. Natural products - owing to their diverse sources, structural complexity, and favorable safety profiles - have attracted growing research interest. However, a systematic synthesis comparing their anti-fatigue effects via gut microbiota modulation across different sources is lacking. SCOPE AND APPROACH: We systematically searched PubMed, Web of Science, the Cochrane Library, and CNKI for original studies that administered natural products and concurrently assessed gut microbiota changes and anti-fatigue outcomes. Twenty-six studies (25 animal experiments and 1 human trial) were included and categorized into seven groups by source and chemical characteristics. A descriptive systematic review was conducted to identify common mechanisms and source-specific differentiations. KEY FINDINGS AND CONCLUSIONS: The enrichment of short-chain fatty acid (SCFA)-producing bacteria and the activation of the SCFA-AMPK/PGC-1α axis were shared core events across all product categories. However, source-dependent mechanistic divergences emerged: polysaccharides acted primarily as fermentable substrates with an optimal dose window; polyphenols and saponins exerted dual modulation on both microbiota and host signaling pathways; compound extracts achieved systemic synergy through functional complementation; marine- and animal-derived products exhibited unique targeting profiles and rapid action. Intestinal barrier maintenance and brain-gut axis regulation further extended the anti-fatigue repertoire. Collectively, natural products possess a solid mechanistic basis for alleviating exercise-induced fatigue via gut microbiota remodeling. The differentiated characteristics of these methods in targeting precision and pathway engagement provide a theoretical foundation for designing precision intervention strategies tailored to specific fatigue contexts.

Humans↗

PubMed2026

How AI-supported intelligent systems support infection prevention and control training in healthcare: A systematic review of educational functions and outcomes.

AIMS: Artificial intelligence (AI)-supported intelligent systems have been increasingly incorporated into infection prevention and control (IPC) education and training, primarily to support the monitoring of observable behaviors and the provision of feedback. However, existing evidence has focused largely on short-term compliance outcomes, with limited synthesis of the educational role of AI-supported intelligent systems in supporting sustained IPC competence. This systematic review examined how AI-supported intelligent systems have been designed and used to support IPC education and training, with a focus on system characteristics, educational functions, and reported outcomes. DESIGN: A systematic literature search was conducted across the PubMed/MEDLINE, Embase, Cochrane, and CINAHL databases. DATA SOURCES: A total of 18 studies met the inclusion criteria. Findings were qualitatively synthesized according to system design characteristics, educational functions, and outcome domains. REVIEW METHODS: Methodological quality was appraised using the Mixed Methods Appraisal Tool. RESULTS: Most AI-supported intelligent systems focused on hand hygiene and relied on fully automated monitoring systems to capture behaviors and provide performance feedback. Educational functions were predominantly limited to performance assessment, automated feedback, and reminders. Outcomes were mainly measured using compliance or performance metrics, whereas sustained behavioral change and decision quality were rarely assessed. CONCLUSIONS: AI-supported intelligent systems have been used primarily to reinforce short-term IPC performance and compliance. However, their current applications for supporting sustained competence over time remain limited. The findings of this review suggest that AI-supported intelligent systems may serve as maintenance-oriented educational support by extending learning beyond initial instruction through repeated practice and feedback. Future research should prioritize outcome measures that capture the durability of performance and decision-making processes to better align AI-supported intelligent systems used in IPC education and training with the educational demands of clinical practice.

Humans↗

PubMed2026

Outcomes of patients with myelofibrosis treated with ruxolitinib and anemia-supporting medications.

OBJECTIVE: This post hoc analysis of the phase 3b JUMP trial evaluated addition of anemia-supporting medications to ruxolitinib in patients with myelofibrosis and anemia. METHODS: 101 patients with baseline hemoglobin <12.0 g/dL initiated an erythropoiesis-stimulating agent (ESA) or danazol <3 months post-enrollment and maintained ESA/danazol ≥3 months; 97% initiated ESAs. Patients enrolled in JUMP who had hemoglobin <12.0 g/dL but did not initiate ESAs/danazol within 3 months were evaluated as an unmatched comparator. Total JUMP population data were also analyzed for spleen length (≥50% reduction from baseline) and symptom response (≥6.5-point improvement in FACT-Lym score). RESULTS: Baseline characteristics were similar to comparator JUMP patients (no ESAs/danazol within 3 months, n = 1242). Mean total daily ruxolitinib dose remained >25 mg. Week 24 spleen length response was achieved by 37% of patients; 26% achieved symptom response, similar to the comparator population (28% and 26%, respectively) and comparable to the total JUMP population (N = 2233). Outcomes were similar between the hemoglobin <12.0 g/dL analysis population and patients with baseline hemoglobin <10.0 g/dL (n = 52). In all groups, hemoglobin levels increased after Week 4 following an expected initial decrease. DISCUSSION: This analysis suggests that patients treated with ruxolitinib and anemia-supporting care continued to receive optimal ruxolitinib dosing; spleen-length and symptom response rates in these patients were comparable to the overall JUMP population, the majority of whom did not have anemia. CONCLUSION: Results support use of anemia-supporting medications with ruxolitinib and may allow maintenance of ruxolitinib dose intensity in patients with myelofibrosis and anemia.

Humans↗

PubMed2026

Transcriptomics reveals species-specific adaptive strategies to calorie restriction in two Argopecten scallops with distinct lifespans.

Calorie restriction (CR) is a well-established non-genetic intervention for lifespan extension in multiple model organisms. Seasonal food shortage in cold and temperate seas may mimic CR, inducing in bivalves a response similar to that in vertebrates and thereby prolonging life expectancy. However, the relationship and the mechanism underlying the food availability and lifespan in bivalves remain largely unexplored. Two closely related scallop species the short-lived warm-water Argopecten irradians (lifespan <2 years) and the longer-lived cold-water Argopecten purpuratus (7-10 years) provide an ideal comparative system to investigate species-specific adaptive strategies. In this study, we subjected both species to CR for 30 and 56 days and performed comparative transcriptomic profiling, weighted gene co-expression network analysis (WGCNA), and physiological assays to elucidate their distinct molecular responses. Transcriptomic analysis revealed that A. purpuratus exhibited substantially more DEGs than A. irradians at both time points under CR, with both species showing downregulation of metabolic pathways but to different extents. A. irradians mounted an early nutrient-sensing response at 30 days (IGF1R, PIK3R3, INSR suppression), indicating acute sensitivity to limitation; by contrast, A. purpuratus displayed delayed FoxO activation at 56 days, along with its downstream effectors NFKBIA, CREB3L4, and SMAD4, suggesting a gradual adaptive program may link to its extended lifespan. WGCNA identified three negatively correlated modules in each species, with coral2 being the most prominent in A. irradians and darkolivegreen in A. purpuratus. The former was dominated by ciliary motility genes, whereas the latter featured coordinated repression of oxidative phosphorylation. Additionally, both species exhibited conserved suppression of mTOR/S6K growth signaling and activation of cellular maintenance programs. Collectively, these findings expand the understanding of CR-mediated longevity regulation in bivalves and provide candidate gene resources for future functional studies and breeding programs.

Pectinidae↗

PubMed2026

Cognitive-behavioral therapy for post COVID-19 condition: A pilot randomized controlled trial.

BACKGROUND: The post COVID-19 condition (PCC) is a disabling condition with urgent need for effective treatments. This pilot randomized controlled trial examined the feasibility and efficacy of a cognitive-behavioral therapy (CBT) for PCC in a parallel-group design. METHODS: N = 53 individuals with PCC were randomized to CBT (n = 27) or 16-week wait-list control (WLC) condition (n = 26). One participant allocated to WLC was excluded after randomization, resulting in an intention-to-treat (ITT) sample of N = 52 participants (CBT: n = 27, age: M = 48.59, SD = 11.52, 77.8% female; WLC: n = 25, Age: M = 48.44, SD = 9.81, 60% female). CBT comprised eight group and five individual sessions addressing cognitive and behavioral factors of symptom maintenance (treatment duration if completed: M = 14 weeks, SD = 1 week). Primary outcomes included fatigue (FSS), overall somatic symptom burden (PHQ-15), and respiratory and cardiovascular symptoms (SBQ™-LC "Breathing" and "Circulation"), assessed at pre-, post-assessment, and follow-up. RESULTS: Participants receiving CBT showed a significant medium-sized reduction in fatigue directly after treatment compared to the WLC condition (d = -0.58, p = .045), whereas the WLC group showed a significant increase in overall somatic symptoms (d = 0.60, p = .027). Results for respiratory symptoms were mixed, showing inconsistent patterns across analyses. Retrospectively assessed feasibility and treatment satisfaction were good, with few adverse effects reported. CONCLUSIONS: This pilot trial suggests the feasibility and preliminary efficacy of CBT for PCC. Larger RCTs with active control groups should confirm these findings.

Humans↗

PubMed2026

Integrated miRNA-mRNA profiling reveals candidate regulatory relationships associated with high-fat diet-induced muscle lipid deposition in black seabream (Acanthopagrus schlegelii).

High-fat diets are increasingly used in aquaculture due to their protein-sparing effects; however, the post-transcriptional regulatory mechanisms of fish muscle in response to high-fat diets (HFD) remain unclear. In this study, juvenile black seabream were fed either a normal-fat diet (NFD) or a HFD to investigate the miRNA-mRNA regulatory network associated with diet-induced muscle lipid deposition. Oil Red O staining and biochemical analysis showed that high-fat diet feeding markedly increased lipid droplet accumulation and crude lipid content in muscle, indicating significant induction of muscle lipid deposition. Integrated mRNA and miRNA expression profiling revealed substantial transcriptomic and post-transcriptional responses to high-fat diet challenge. A total of 271 differentially expressed genes were identified, including 120 upregulated and 151 downregulated genes. Through combined target prediction and expression correlation analysis, thirteen candidate inverse miRNA-mRNA relationships were subsequently identified, and RT-qPCR supported the expression patterns of selected miRNAs and mRNAs. These pairs included miR-499-x-dmgdh, miR-499-y-gatm, miR-727-y-ass1, miR-4649-x-foxo4, miR-9129-z-myl7, and several novel miRNA-mediated interactions involving adk, chst11, lypla2, frem2, kcnc4, wars1, bag2, and capn2. Functional analysis suggested that these regulatory pairs were mainly associated with metabolic adaptation, structural remodeling, and cellular stress responses. In particular, gatm, dmgdh, ass1, and adk were associated with energy metabolism-related processes, including pathways previously linked to Ampk regulation, whereas myl7, frem2, and kcnc4 may contribute to muscle structural maintenance and excitability regulation. Overall, this study provides candidate miRNA-mRNA regulatory relationships potentially involved in high-fat diet-induced muscle lipid deposition and adaptive remodeling in black seabream, offering a basis for future functional studies on muscle metabolism and quality regulation in marine fish.

Animals↗

PubMed2026

Five-year outcomes in a randomised controlled trial of prolonged exposure therapy and supportive counselling for post-traumatic stress disorder in adolescents: a task-shifted intervention.

BACKGROUND: Cognitive-behavioural therapies with a trauma focus are effective in reducing posttraumatic stress disorder and other psychological distress in adolescents. Long-term follow-up data on adolescents treated for PTSD remain scarce, with few studies extending beyond 12 months after treatment completion. OBJECTIVE: To evaluate the maintenance of treatment gains in a comparative study of effectiveness of PE-A and SC up to 60 months post-treatment. METHOD: Sixty-three adolescents diagnosed with PTSD were randomly assigned to either treatment, provided by newly trained and supervised non-specialist health workers. The primary outcome measure was PTSD symptom severity, as independently assessed on the Child PTSD Symptom Scale (CPSS). We report on the 60-month post-treatment follow-up, building on post-treatment, 3-month, 6-month, 12-month and 24-month post-treatment data that have been published previously. RESULTS: Participants in both treatment groups maintained a significant reduction in PTSD symptoms up to 60-months post-treatment (F (7, 343) = 2.86, p < .01). Participants receiving prolonged exposure experienced greater improvement on the CPSS at all follow-up assessment timepoints, except for the 60-month FU (p = .28; g = 0.33). CONCLUSION: Adolescents with PTSD continued to maintain treatment gains up to 60-months post-treatment. These data, along with findings from the original RCT, indicate that a brief treatment protocol (averaging 9 sessions of PE-A or SC) in a LMIC, task-shifted to be delivered by nurses without prior psychotherapy experience, led to lasting improvements in PTSD and comorbid symptoms for up to five years. The sustained benefits and improved functioning over the first few years post-treatment support expanding both treatments, especially PE-A, in community settings.

Humans↗

PubMed2026

Adherence and efficacy of the 0 - 7 - 21-day versus the 0 - 1 - 6-month hepatitis B vaccination schedules among people who use drugs: a two-year randomized controlled trial.

BACKGROUND: To compare the adherence and efficacy between the 0 - 7 - 21-day and the 0 - 1 - 6-month hepatitis B virus (HBV) vaccination schedules among people who use drugs (PWUD) in China. RESEARCH DESIGN AND METHODS: A randomized controlled trial was conducted in 1261 HBV-susceptible PWUD from compulsory isolated detoxification centers (CIDCs) and methadone maintenance treatment (MMT) clinics in Xi'an. A 20 µg per-dose vaccine was used. HBV surface antibody (anti-HBs), surface antigen, and core antibody were tested at months 7, 15, and 22 after the first dose. RESULTS: Third-dose coverage was significantly higher in the 0 - 7 - 21-day group (74.40%) than in the 0 - 1 - 6-month group (51.58%, p < 0.001), mainly driven by participants from CIDCs (77.75% vs. 45.69%). Anti-HBs positive rates at months 7, 15, and 22 among participants who completed all three doses were significantly higher for the 0 - 1 - 6-month schedule (90.71%, 76.82%, and 67.35%) than for the 0 - 7 - 21-day schedule (74.23%, 49.40%, and 40.95%; all p < 0.001). HBV infection incidence was similar between schedules, but significantly different between vaccinees and non-vaccinees (p = 0.018). CONCLUSIONS: The 0 - 7 - 21-day schedule substantially enhances three-dose completion in PWUD, but induces a notably weaker anti-HBs response and persistence. Schedules should be selected based on the management models for PWUD and their individual characteristics. CLINICAL TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR1900022403).

Humans↗

PubMed2026

Using Organoids to Unlock the Potential of Human Torpor for Spaceflight.

PURPOSE OF REVIEW: This paper reviews the current understanding of the potential for humans to enter a state of torpor/hibernation, and discusses the possibility of inducing torpor in astronauts for long-duration space travel, including some of the physiological, technological, and ethical considerations associated with its implementation. By exploring means to induce torpor in various human organoid systems, we hope such research can provides insights to comprehensive solutions to overcome some of the major hurdles that limit the potential for human to enter a state of torpor during long-duration deep-space missions, and contribute to the ongoing efforts to make such missions more feasible and safer for astronauts. RECENT FINDINGS: On future deep space missions such as NASA's planned missions to the Moon, Mars, and near-Earth asteroids, astronauts will be continuously exposed to environments that are radically different from those on Earth, each presenting multiple logistical and physiological challenges. Beyond the well-documented physiological effects of microgravity, space travelers will encounter a complex radiation environment that may contribute to significant short- and long-term adverse effects on human physiology and increase the risk of cancer and other diseases. Besides these physical challenges, life support systems must also be designed to mitigate psychological impacts of long-term isolation and confinement - all of which collectively pose formidable engineering problems. Hibernation/torpor is a state of prolonged inactivity and metabolic depression used by a wide variety of mammals to survive periods of cold temperatures and food scarcity, including some primates and perhaps even an extinct early line of hominins that lived nearly half a million years ago. Since modern humans share common ancestry with these hominins and hibernating primates, it is likely the human genome encodes the necessary genetic information to hibernate, or at least enter the similar, more transient state of torpor. The reduced body activity, lowered metabolism, and decreased energy requirements that characterize torpor suggest that developing means of inducing such a state in astronauts could address these challenges, including providing a degree of radioprotection. SUMMARY: This review explores the potential application of human torpor as a countermeasure to address the many challenges posed by long-duration spaceflight beyond low-Earth orbit (LEO), discusses various natural hibernating model systems for studying means of inducing a torpor-like state in humans, and highlights the vast potential of using human organoids to test and validate mechanisms that govern induction and maintenance of torpor to identify the means to one day safely induce this state in astronauts to provide additional protection from the myriad stressors of spaceflight.

Astronaut Health↗