Degradable bone cement has superior osteoconductivity and plasticity and is commonly used to treat defects greater than the critical-size. Magnesium gallate metal–organic frameworks (MOFs) (Mg-MOF), with antibacterial and anti-inflammatory properties, are doped into a composite cement composed of calcium sulfate, calcium citrate, and dicalcium hydrogen phosphate anhydrous (CS/CC/DCPA). The doping of the Mg-MOF slightly influences the microstructure and curing properties of the composite cement, with the mechanical strength of the cement displaying a significant increase from 27 to 32 MPa. Antibacterial tests reveal that the Mg-MOF bone cement has excellent antibacterial characteristics and can effectively inhibit bacterial growth in 4 h (Staphyloccocus aureus survival rate <10%). Herein, lipopolysaccharide (LPS)-induced macrophage models are used to investigate the anti-inflammatory characteristics of composite cement. The Mg-MOF bone cement can regulate the inflammatory factors and polarization of macrophages (M1 and M2). In addition, the composite cement promotes cell proliferation and osteo-differentiation of mBMSCs, and the activity of alkaline phosphatase and calcium nodules are increased. The bone related transcription factor and specific proteins, such as runt-related transcription factor 2 (Runx2), bone morphogenetic protein 2, osteocalcin (OCN), osteopontin (OPN), and collagen type 1 (COL1), were highly expressed by the Mg-MOF bone cements. Therefore, Mg-MOF doped CS/CC/DCPA bone cement is multifunctional for bone repair, which will promote bone formation and avoid the infection of wounds, and it is suitable for use with non-load-bearing bone defects.
10 January 2022 in Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy
Osteoporosis is a growing public health concern worldwide. To avoid extra surgeries, developing biodegradable bone cement is critical for the treatment of osteoporosis. Herein, we designed calcium phosphate/calcium sulfate cement reinforced with sodium carboxymethyl cellulose (CMC/OPC). It presents an appropriate physicochemical performance for clinical handling. Meanwhile, CMC/OPC bone cement promotes osteogenic differentiation in vitro. Results of the immune response in vitro and in vivo confirmed that increasing the cellulose content triggered macrophage switching into the M2 phenotype and CMC/OPC exhibited significant anti-inflammation. Furthermore, in vitro and in vivo degradation demonstrated that cellulose tailors the degradation rate of composite bone cement, which achieved a linear degradation process and could degrade by more than 90% for 12 weeks. In summary, the composite bone cement CMC/OPC is a promising candidate for bone repair applications.
5 February 2020 in Journal of Applied Polymer Science