Impact of Polyrhodanine Manganese Ferrite Binary Nanohybrids (PRHD@MnFe2O4) on Osteoblasts and Osteoclasts Activities-A Key Factor in Osteoporosis Treatment.

Osteoporosis is characterized by the reduction of bone mineral density and the weakness of the bone strength leading to fractures. Searching for new compounds that stimulate bone activity and their ability to reconstruct seems to be a promising tool in osteoporosis treatment. Here, we performed analyses comparing the impact of polyrhodanine (PRHD) and its derivatives on the viability (anti-proliferative tests), morphology and mitochondrial network (confocal microscopy) towards pre-osteoblasts (MC3T3-E1 cell line) and osteoclasts (4B12 cell line). Moreover, we assessed the expression of genes associated with the apoptosis, inflammation and osteogenic differentiation by qPCR technique. Our results clearly demonstrated that PRHD and its modification at ratio 10/90 significantly improves the pre-osteoblast's proliferative abilities, while reducing osteoclast function. The observed effects were strongly correlated with the cytoskeleton and mitochondrial network development and arrangement. Additionally, the expression profile of genes revealed enhanced apoptosis of osteoclasts in the case of PRHD and its modification at ratio 10/90. Moreover, in this case we also observed strong anti-inflammatory properties demonstrated by decreased expression of Il1b, Tnfa and Tgfb in pre-osteoblasts and osteoclasts. On the other hand, enhanced expression of the markers associated with bone remodeling, namely, osteopontin (OPN), osteocalcin (OCL) and alkaline phosphatase (ALP), seem to confirm the role of PRHD@MnFe2O4 in the promotion of differentiation of pre-osteoblasts through the ALP-OPN-OCL axis. Based on these observations, PRHD@MnFe2O4 could be a potential agent in osteoporosis treatment in future, however, further studies are still required.

Co0.5Mn0.5Fe2O4@PMMA Nanoparticles Promotes Preosteoblast Differentiation through Activation of OPN-BGLAP2-DMP1 Axis and Modulates Osteoclastogenesis under Magnetic Field Conditions.

The prevalence of osteoporosis in recent years is rapidly increasing. For this reason, there is an urgent need to develop bone substitutes and composites able to enhance the regeneration of damaged tissues which meet the patients' needs. In the case of osteoporosis, personalized, tailored materials should enhance the impaired healing process and restore the balance between osteoblast and osteoclast activity. In this study, we fabricated a novel hybrid material (Co0.5Mn0.5Fe2O4@PMMA) and investigated its properties and potential utility in the treatment of osteoporosis. The material structure was investigated with X-ray diffraction, Fourier-transform infrared spectroscopy with attenuated total reflectance, FTIR-ATR, transmission electron microscopy (TEM), scanning electron microscopy (SEM) and selected area (electron) diffraction (SAED). Then, the biological properties of the material were investigated with pre-osteoblast (MC3T3-E1) and pre-osteoclasts (4B12) and in the presence or absence of magnetic field, using RT-qPCR and RT-PCR. During the studies, we established that the impact of the new hybrids on the pre-osteoblasts and pre-osteoclasts could be modified by the presence of the magnetic field, which could influence on the PMMA covered by magnetic nanoparticles impact on the expression of genes related to the apoptosis, cells differentiation, adhesion, microRNAs or regulating the inflammatory processes in both murine cell lines. In summary, the Co0.5Mn0.5Fe2O4@PMMA hybrid may represent a novel approach for material optimization and may be a way forward in the fabrication of scaffolds with enhanced bioactivity that benefits osteoporotic patients.

Efficient non-contact heat generation on flexible, ternary hydroxyapatite/curdlan/nanomagnetite hybrids for temperature controlled processes.

The ternary HAp/curdlan/nanomagnetite hybrids with ceramic and polymer phase incorporation of magnetite nanoparticles (MNPs) were fabricated to study their heating ability under action of the alternating magnetic field (AMF), 808 nm near infrared laser radiation (NIR) and their synergic stimulation. The energy conversion was evaluated in terms of the specific absorption rate (SAR) as a function of the MNPs concentration in composites and to estimate their potential in temperature-controlled regenerative processes and hyperthermia. Measurements were carried out on dry and Ringer's solution soaked composite materials in order to mimic in situ conditions. It was found that the MNPs release during prolonged experiment is limited and has no significant effect on energy conversion emphasizing stability of the hybrids. Incorporation of the MNPs in polymer phase of the hybrid can additionally limit particle leaking as well as plays a role as insulating layer for the heat dissipation lowering the risk of sample overheating. In general, it was shown that maximum temperature of hybrid can be achieved in a relatively short time of exposure to stimulating factors whereas its control can be done through optimization of experiment conditions. MNPs incorporation into the curdlan (polymer phase) lead to strengthening of the mechanical properties of the whole network.

Multifunctional Properties of Binary Polyrhodanine Manganese Ferrite Nanohybrids-From the Energy Converters to Biological Activity.

The PRHD@MnFe2O4 binary hybrids have shown a potential for applications in the biomedical field. The polymer cover/shell provides sufficient surface protection of magnetic nanoparticles against adverse effects on the biological systems, e.g., it protects against Fenton's reactions and the generation of highly toxic radicals. The heating ability of the PRHD@MnFe2O4 was measured as a laser optical density (LOD) dependence either for powders as well as nanohybrid dispersions. Dry hybrids exposed to the action of NIR radiation (808 nm) can effectively convert energy into heat that led to the enormous temperature increase ΔT 170 °C (>190 °C). High concentrated colloidal suspensions (5 mg/mL) can generate ΔT of 42 °C (65 °C). Further optimization of the nanohybrids amount and laser parameters provides the possibility of temperature control within a biologically relevant range. Biological interactions of PRHD@MnFe2O4 hybrids were tested using three specific cell lines: macrophages (RAW 264.7), osteosarcoma cells line (UMR-106), and stromal progenitor cells of adipose tissue (ASCs). It was shown that the cell response was strongly dependent on hybrid concentration. Antimicrobial activity of the proposed composites against Escherichia coli and Staphylococcus aureus was confirmed, showing potential in the exploitation of the fabricated materials in this field.