ROS-Induced Downregulation of LncRNA H19 Impairs Osteogenic Differentiation Without Triggering Senescence
Oxidative stress is a critical determinant of osteoblast dysfunction and age-related bone loss, yet the contribution of RNA-based regulatory mechanisms to stress-responsive gene regulation remains poorly understood. Our previous work demonstrated that protein arginine deiminase 2 (PADI2) is downregulated by reactive oxygen species (ROS), promoting cellular senescence and impairing osteoblast differentiation, highlighting the complexity of oxidative stress-responsive regulatory pathways. Here, we identify the long non-coding RNA H19 as a key regulator of osteogenic gene expression under oxidative stress conditions that functions independently of cellular senescence. Integrative transcriptomic analyses revealed that H19 expression is coordinately regulated by ROS accumulation and PADI2 deficiency, positioning H19 at the center of oxidative stress-responsive transcriptional networks. Functional studies in MC3T3-E1 cells demonstrated that H19 depletion markedly impaired osteogenic differentiation without inducing senescence-associated phenotypes, thereby distinguishing its role from canonical ROS-driven senescence pathways. Mechanistically, H19 modulates osteogenic gene programs through a miR-193a-3p and HMGB1 regulatory axis, fine-tuning transcriptional outputs under oxidative stress. Consistently, H19 overexpression enhanced bone regeneration in a mouse calvarial defect model, supporting its physiological relevance in vivo. Together, these findings uncover an lncRNA-centered regulatory mechanism that controls oxidative stress-responsive osteogenic gene expression independently of cellular senescence, expanding the functional landscape of H19 in bone biology.