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Mechanistic Study of Hypoxia-Mediated Regulation of Osteoblast Senescence via ATP6V1A-Dependent Modulation of Metabolic Remodeling
by
,
Hefang Xiao
1,2,3,†,
Yi Chen
1,2,3,†,
Xuening Liu
1,2,3,
Rongjin Chen
1,2,3,
Chenhui Yang
1,2,3,
Fei Yang
1,2,3,
Changshun Chen
1,2,3,
Bin Geng
1,2,3 and
Yayi Xia
1,2,3,* 1
Department of Orthopaedics, Lanzhou University Second Hospital, Lanzhou 730030, China
2
Gansu Province Orthopaedic Clinical Medicine Research Center, Lanzhou 730030, China
3
Gansu Province Intelligent Orthopedics Industry Technology Center, Lanzhou 730030, China
*
Author to whom correspondence should be addressed.
†
These authors contributed equally to this work.
Biology 2025, 14(12), 1801; https://doi.org/10.3390/biology14121801
Submission received: 28 October 2025
/
Revised: 11 December 2025
/
Accepted: 14 December 2025
/
Published: 18 December 2025
(This article belongs to the Special Issue Cellular Senescence in Development, Regeneration, Aging, and Cancer)
Simple Summary
Healthy bones rely on the activity of special bone-forming cells that gradually lose their strength and function as people age. This aging process contributes to osteoporosis and other bone-weakening conditions, yet the reasons why these cells age are still not fully understood. In our study, we explored how low-oxygen conditions, which naturally exist inside the body, influence the aging of bone-forming cells. We discovered that low oxygen reduces harmful molecules called reactive oxygen species, improves cellular energy balance, and slows the aging process of these cells. We also identified a protein called ATP6V1A that becomes less active under low-oxygen conditions and plays a central role in controlling stress and energy use inside the cells. When we reduced this protein in mice, their bone microstructural parameters improved, consistent with reduced cellular stress. Our findings reveal a previously unknown connection between oxygen levels, cellular stress, energy metabolism, and bone cell aging. This work may help guide the development of new strategies to maintain bone health and prevent age-related bone diseases in the future.
Abstract
Background: Osteoblast senescence constitutes one of the major mechanisms in bone degeneration and is under tight regulation by metabolism and oxidative stress. While hypoxia has recently emerged as an important microenvironmental factor influencing the function of bone cells, its role in osteoblast senescence and metabolic regulation has yet to be defined. Methods: The present work entails hypoxia-modulated osteoblast senescence at one level, transcriptomic and metabolomic sequencing, and two levels, in vitro MC3T3-E1 and in vivo AAV-shAtp6v1a mouse models. In transcriptome profiling, hypoxia-responsive genes were identified, whereas non-targeted metabolomics was used to uncover metabolic alterations induced by ATP6V1A knockdown. Oxidative stress and mitochondrial function were assessed by qRT-PCR, Western blotting, SA-β-Gal staining, ROS detection, JC-1 mitochondrial potential, and immunofluorescence. Micro-CT, H&E, Masson, and immunohistochemistry studies were performed to investigate bone structure and protein expression in vivo. Results: Hypoxia markedly mitigated osteoblast senescence, decreasing p53 and p21 expressions and the number of SA-β-Gal-positive cells. It reduced intracellular ROS levels and increased HK2 and LDH expression, decreased ATP, and increased lactate, hinting at a shift toward glycolysis. Transcriptome analysis identified ATP6V1A as one of the major hypoxia-downregulated genes. Knockdown of ATP6V1A reduced ROS levels, inhibited p21 expression, improved mitochondrial function. Metabolomics disclosed remapping pathways in glycolysis, lipid, and amino acid metabolism. Conclusion: This study identifies a “Hypoxia–ATP6V1A–Oxidative Stress–Metabolic Remodeling–Anti-Senescence” axis, demonstrating that hypoxia delays osteoblast senescence by downregulating ATP6V1A, suppressing oxidative stress, and reprogramming metabolism, providing new insights and potential therapeutic targets for bone degenerative diseases.
Keywords:
cellular senescence; hypoxia; osteoblast; ATP6V1A; metabolism; biomarkers
