Titanium-based substrate modified with nanoenzyme for accelerating the repair of bone defect

Area of Science:

• Biomaterials Science
• Orthopedic Surgery
• Nanotechnology

Background:

• Titanium (Ti) and its alloys are standard orthopedic implant materials.
• Implantation can cause oxidative stress (OS) by increasing reactive oxygen species (ROS), inhibiting bone regeneration and leading to surgical failure.
• Nanoscale manganese dioxide (MnO2) exhibits H2O2-like enzyme activity, suggesting potential for mitigating OS.

Purpose of the Study:

• To develop a MnO2 nanocoating on a Ti substrate to reduce OS.
• To evaluate the effect of the modified Ti substrate on mesenchymal stem cell (MSC) behavior.
• To assess the in vivo efficacy of the modified Ti implant in promoting bone regeneration.

Main Methods:

• Fabrication of MnO2 nanocoating on Ti substrate using alkaline thermal and hydrothermal treatment.
• Characterization of the nanocoating using SEM, XRD, and XPS.
• In vitro assessment of H2O2 scavenging, ROS reduction, and MSCs' adhesion, proliferation, and osteogenic differentiation.
• In vivo evaluation of bone regeneration using histological and immunohistochemical staining.

Main Results:

• Successful fabrication of MnO2 nanocoating on Ti substrate confirmed by SEM, XRD, and XPS.
• Demonstrated efficient elimination of H2O2 and reduction of ROS in vitro.
• Enhanced MSC adhesion, proliferation, and osteogenic differentiation, evidenced by cell assays and gene expression (qRT-PCR).
• In vivo studies showed reduced OS and promoted bone tissue regeneration.

Conclusions:

• The MnO2-nanocoated Ti implant effectively reduces OS and promotes osseointegration.
• This approach offers a promising strategy for developing functional orthopedic implants.
• The findings provide new methods for improving implant performance in orthopedic applications.