Related Experiment Video
Updated: Jan 19, 2026
Ameliorating Osteoarthritis in Mice Using Silver Nanoparticles
Published on: June 2, 2023
Manganese dioxide nanoparticles protect cartilage from inflammation-induced oxidative stress
Shreedevi Kumar1, Isaac M Adjei1, Shannon B Brown1
1J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, 1275 Center Drive Biomedical Sciences Building JG-56, P.O. Box 116131, Gainesville, FL 32611-6131, USA.
Abstract:
Oxidative stress has been implicated in the pathogenesis of osteoarthritis and has become an important therapeutic target. Investigations of various antioxidant supplements, reactive oxidative species (ROS) pathway mediators, and free radical scavengers for treating osteoarthritis have demonstrated common disadvantages including poor bioavailability and stability, as well as rapid joint clearance or release profiles from delivery vehicles. Moreover, these therapies do not target cartilage, which irreversibly degenerates in the presence of oxidative stress. The goal of this study was to engineer a nanoparticle system capable of sustained retention in the joint space, localization to cartilage, and mitigation of oxidative stress. Towards this goal, ROS scavenging manganese dioxide nanoparticles with physicochemical properties (less than 20 nm and cationic) that facilitate their uptake into cartilage were developed and characterized. These particles penetrated through the depth of cartilage explants and were found both in the extracellular matrix as well as intracellularly within the resident chondrocytes. Furthermore, the particles demonstrated chondroprotection of cytokine-challenged cartilage explants by reducing the loss of glycosaminoglycans and release of nitric oxide. Quantitative PCR analysis revealed that the particles mitigated impacts of oxidative stress related genes in cytokine-challenged chondrocytes. When injected intra-articularly into rats, the particles persisted in the joint space over one week, with 75% of the initial signal remaining in the joint. Biodistribution and histological analysis revealed accumulation of particles at the chondral surfaces and colocalization of the particles with the lacunae of chondrocytes. The results suggest that the manganese dioxide nanoparticles could be a promising approach for the chondroprotection of osteoarthritic cartilage.
Insights
New manganese dioxide nanoparticles effectively target cartilage, mitigating oxidative stress and protecting against osteoarthritis progression. These nanoparticles show sustained joint retention and chondroprotective effects, offering a promising therapeutic strategy.
Area of Science:
- Biomedical Engineering
- Nanotechnology
- Osteoarthritis Research
Background:
- Oxidative stress is a key factor in osteoarthritis (OA) pathogenesis, making it a significant therapeutic target.
- Current antioxidant therapies for OA suffer from poor bioavailability, stability, and rapid clearance, failing to effectively target cartilage.
- Existing treatments do not address cartilage degeneration directly, highlighting the need for novel delivery systems.
Purpose of the Study:
- To engineer a nanoparticle system for sustained intra-articular retention and cartilage localization.
- To develop nanoparticles capable of mitigating oxidative stress within the joint space.
- To create a targeted delivery system for chondroprotection in osteoarthritis.
Main Methods:
- Development and characterization of manganese dioxide nanoparticles (<20 nm, cationic) for cartilage uptake.
- Assessment of nanoparticle penetration in cartilage explants (extracellular and intracellular).
- Evaluation of chondroprotection in cytokine-challenged cartilage and in vivo studies in rats.
Main Results:
- Manganese dioxide nanoparticles penetrated cartilage depth, localizing extracellularly and intracellularly within chondrocytes.
- Particles demonstrated chondroprotection by reducing glycosaminoglycan loss and nitric oxide release.
- In vivo studies showed sustained joint retention (>1 week) and accumulation at chondral surfaces.
Conclusions:
- Engineered manganese dioxide nanoparticles show potential for sustained joint retention and cartilage targeting.
- These nanoparticles effectively mitigate oxidative stress and offer chondroprotection in osteoarthritis models.
- The developed system represents a promising approach for the treatment of osteoarthritic cartilage.
