Hydrogen-Releasing Gel Heals Infected Bone Defects in Rats
- Authors
- Chunru Kong, Chao Si, Haofeng Liu, Yawen Wang, Jiakai Qiao, Xiaoduo Tang, Hongchen Sun, Junhu Zhang, Bei Chang
- Journal
- Materials Today Bio
- Year
- 2025
- DOI
- 10.1016/j.mtbio.2025.102295
- Study Type
- Rat
- Outcome
- Positive
- Peer Reviewed
- Yes
- Country
- China
- Health Condition
- Infected Bone Defects
- Body System
- Musculoskeletal
TL;DR
A hydrogen- and magnesium-releasing injectable hydrogel scaffold reduced oxidative stress and promoted vascularized bone regeneration in infected bone defects in rats.
Key Finding
A hydrogen-releasing hydrogel scaffold achieved a 6.27-fold improvement in bone volume compared to controls in a rat model of infected bone defects.
Summary
Researchers developed a special gel-like scaffold containing magnesium that releases hydrogen gas to help repair infected bone defects (areas where bone is damaged and infected). The scaffold works by reducing harmful molecules called reactive oxygen species that cause inflammation and damage to cells' energy-producing structures (mitochondria). In rats with infected bone defects, this hydrogen-releasing scaffold produced about 6 times more new bone growth compared to untreated controls after 4 weeks.
Practical Takeaway
This is early-stage research conducted only in rats, so it cannot yet be applied to human treatment. The study suggests that sustained hydrogen release may help address oxidative stress and mitochondrial dysfunction in infected bone healing, but human trials would be needed to determine if this approach is safe and effective for patients.
Abstract
The repair of infected bone defects (IBDs) presents a significant clinical challenge due to recurrent infections and inflammation. Characterized by reactive oxygen species (ROS) bursts and mitochondrial dysfunction, IBDs generates to a vicious oxidation-inflammation cycle that impairs bone remodeling. To address this, we developed a double-network hydrogel scaffold composed of phenylboronic acid-modified quaternary chitosan and glycidyl methacrylated poly(vinyl alcohol) (QP-P), crosslinked via dynamic boronic ester bonds and covalent bonds, loaded with magnesium microspheres (Mg spheres) (QP-P/Mg). This double-crosslinking network confers excellent injectability and tissue adhesion while integrating potent antibacterial, ROS-scavenging, pro-angiogenic, and osteogenic functions. Notably, Mg spheres enable controlled hydrolysis through a boronic ester-magnesium ion (Mg2+) complexation mechanism, providing sustained release of hydrogen (H2) and Mg2+, with H2 potently alleviating oxidative stress and restoring mitochondrial homeostasis via the Nrf2/HO-1 pathway and Mg2+ promoting vascularized bone regeneration. In a rat IBDs model, QP-P/Mg achieved substantial bone regeneration, with a BV/TV ratio of 45.32 % ± 8.22 % after 4 weeks, representing a 6.27-fold improvement over controls. These findings underscore the potential of this H2-releasing hydrogel scaffold with multifunctional properties to promote vascularized bone regeneration in IBDs through ROS elimination and mitochondrial rehabilitation, offering promising clinical translational opportunities for the treatment of IBDs.