宇宙飛行が幹細胞の老化を加速する(Spaceflight Accelerates Human Stem Cell Aging, UC San Diego Researchers Find)

2025-09-05

2025-09-04 カリフォルニア大学サンディエゴ校(UCSD)

カリフォルニア大学サンディエゴ校の研究で、宇宙飛行がヒト造血幹・前駆細胞(HSPCs)の老化を加速させることが示された。ISSに搭載したAI駆動ナノバイオリアクターで細胞を解析した結果、再生能の低下、DNA損傷増加、テロメア短縮が確認され、老化の典型的兆候が強まっていた。微小重力や放射線によるストレスは炎症やミトコンドリア異常を誘発し、通常は不活性なゲノム領域を活性化させ、免疫低下や疾患リスクの増大につながる可能性がある。ただし、細胞を若い環境に戻すと一部の老化兆候が回復することも示され、介入による修復の可能性が浮上した。本成果は、長期宇宙滞在時の健康管理だけでなく、地上での老化やがんなど加齢関連疾患の理解にも寄与する重要な知見となる。

<関連情報>

宇宙関連造血幹細胞・前駆細胞の老化をナノバイオリアクターで検出 Nanobioreactor detection of space-associated hematopoietic stem and progenitor cell aging

Jessica Pham ∙ Jane Isquith ∙ Larisa Balaian ∙ … ∙ Thomas Whisenant ∙ Ludmil B. Alexandrov ∙ Catriona H.M. Jamieson
Cell Stem Cell Accepted: July 28, 2025
DOI:https://doi.org/10.1016/j.stem.2025.07.013

Graphical abstract

Highlights

Hematopoietic stem and progenitor cell (HSPC) fitness declines post spaceflight
Hallmarks of aging, including base deaminase deregulation, are accelerated post spaceflight
Spaceflight reduces telomere maintenance and HSPC self-renewal
Space-associated HSPC aging can be partially reversed on young stroma

Summary

Human hematopoietic stem and progenitor cell (HSPC) fitness declines following exposure to stressors that reduce survival, dormancy, telomere maintenance, and self-renewal, thereby accelerating aging. While previous National Aeronautics and Space Administration (NASA) research revealed immune dysfunction in low-earth orbit (LEO), the impact of spaceflight on human HSPC aging had not been studied. To study HSPC aging, our NASA-supported Integrated Space Stem Cell Orbital Research (ISSCOR) team developed bone marrow niche nanobioreactors with lentiviral bicistronic fluorescent, ubiquitination-based cell-cycle indicator (FUCCI2BL) reporter for real-time HSPC tracking in artificial intelligence (AI)-driven CubeLabs. In month-long International Space Station (ISS) missions (SpX-24, SpX-25, SpX-26, and SpX-27) compared with ground controls, FUCCI2BL reporter, whole-genome and transcriptome sequencing, and cytokine arrays demonstrated cell-cycle, inflammatory cytokine, mitochondrial gene, human repetitive element, and apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like 3 (APOBEC3) deregulation together with clonal hematopoietic mutations. Furthermore, HSPC functionally organized multi-omics aging (HSPC-FOMA) analyses revealed reduced telomere maintenance, adenosine deaminase acting on RNA1 (ADAR1) p150 self-renewal gene expression, and replating capacity indicative of space-associated HSPC aging that may limit long-duration spaceflight.