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Peroxisome proliferator activated receptor gamma (PPARγ) has been known for their anti-inflammatory effects. But the application of this molecule in implant-induced inflammation has not been clearly studied yet. Here, we determined in vivo anti-inflammatory and osteogenic effects of PPARγ coated dental implant in the rat mandible. We used chitosan gold nanoparticles (Ch-GNPs) as a non viral vector to carry PPARγ plasmid DNA. Ch-GNPs were conjugated with PPARγ plasmid DNA through a coacervation process. Conjugation was cast over titanium (Ti) implants (4.5 × 0.8 mm) by dipping, and implants were installed in rat mandibles. One, 2, 3, and 6 weeks post-implantation, mandibles were examined by microcomputed tomography (µCT), immunohistochemistry, hematoxylin & eosin, and tartrate resistance acid phosphatase (TRAP) staining. In vivo Ch-GNPs/PPARγcoated implants were associated with inhibition of implant induced inflammatory molecules interleukin-1β and receptor activator of nuclear factor kappa-B ligand and enhanced expression of osteogenic molecules like bone morphogenetic protein 2 and 7 (BMP-2/-7) by up-regulating anti-oxidant molecules heme oxygenase-1. µCT demonstrated that PPARγ overexpression increased the density and volume of newly formed bone surrounding the implants compared to control ( n = 4; p < 0.05). Also, PPARγ reduced the number of TRAP positive cells. These results support the view that PPARγ overexpression diminishes inflammation and enhances osteogenesis around the dental implants. Thus, implant coated with anti-inflammatory molecules could have a significant utilization for the preparation of new biomaterials and may serve as prosthetic materials in patients suffering from inflammatory bone disease. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 103B: 587-595, 2015. [ABSTRACT FROM AUTHOR]

The ageing of an inevitable life function is an unavoidable regressive physical process. Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear hormone receptor family. PPAR γ plays an important role in regulating several metabolic pathways. Recently, PPAR γ has been implicated in inflammatory responses and age-related diseases. The aim of this study was to determine the anti-inflammatory reaction of PPAR γ in an induced ageing progress. The late passage of human diploid fibroblasts (HDF), an in vitro ageing model, reveals the biological index materials of ageing. Aged cells showed decreased PPAR γ expression and elevated levels of intracellular adhesion molecule-1 (ICAM-1), an inflammatory molecule. To induce the aged cell phenotype, the middle stage of HDF cells (PD31) were induced stress induced premature senescence (SIPS) with 200 µM H2O2 for 2 h. SIPS-HDF cells showed high levels of ICAM-1, extracellular signal regulated kinase (ERK1/2) activity and matrix metallomatrix protease (MMP-2, -9) activity, and low levels of PPAR γ expression. A reconstitution of SIPS HDF cells with Ad/PPAR γ resulted in the downregulation of ICAM-1, ERK1/2, MMP-2 and -9, and normalized growth of SIPS-HDF cells. Moreover, PPAR γ in aged HDF cells reduced pro-inflammatory molecules and eliminated the formation of reactive oxygen species (ROS) through the ERK1/2 pathway. These results strongly suggest that PPAR γ plays a key role in age-related inflammation and may have clinical applications as a molecular target in the treatment of age-related inflammation. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: This study examined the in vitro cell-material interactions on four different types of titanium surfaces: a polished Ti surface, TiO2 nanotube surfaces fabricated in a fluorinated glycerol solution (TN), fluorinated glycerol solution with 1wt% anionic surfactant sodium dodecyl sulphate (TN-SDS), and fluorinated glycerol solution with 1wt% cationic surfactant cetyl trimethyl ammonium bromide (TN-CTAB), respectively. The surfaces exhibited distinct surface morphologies and geometrical features. Surface energy calculation shows that TN surface enhances the hydrophilic character by significantly increasing the surface energy. The osteoblast cell growth behavior on the four different surfaces was examined using the MC3T3-E1 cell line for 1 day. When the anodized surfaces were compared for the cell-materials interaction, each of the surfaces showed different properties that affected the cell–material interactions. Proliferation of the cells was noticed with distinctive cell-to-cell attachment on the TN surfaces. Good cellular adhesion with extracellular matrix extensions between the cells was noticed in the TN samples. The TiO2 nanotubes grown in the surfactant-assisted fluorinated electrolyte did not show significant cell growth on the surface and some cell death was observed. The cell adhesion, differentiation and alkaline phosphatase activity were more pronounced on the TN surface. The MTT assays also revealed an increase in living cell density and proliferation on the TN surfaces. Overall, a rough surface morphology and surface energy are important factors for better cell material interactions. [Copyright &y& Elsevier]

Purpose: The aim of this study was to determine the effect of insulin growth factor binding protein-3 (IGFBP-3) on the inhibition of glucose oxidative stress and promotion of bone formation near the implant site in a rat model of methylglyoxal (MGO)-induced bone loss., Methods: An in vitro study was performed in MC3T3 E1 cells treated with chitosan gold nanoparticles (Ch-GNPs) conjugated with IGFBP-3 cDNA followed by MGO. An in vivo study was conducted in a rat model induced by MGO administration after the insertion of a dental implant coated with IGFBP-3 ., Results: MGO treatment downregulated molecules involved in osteogenic differentiation and bone formation in MC3T3 E1 cells and influenced the bone mineral density and bone volume of the femur and alveolar bone. In contrast, IGFBP-3 inhibited oxidative stress and inflammation and enhanced osteogenesis in MGO-treated MC3T3 E1 cells. In addition, IGFBP-3 promoted bone formation by reducing inflammatory proteins in MGO-administered rats. The application of Ch-GNPs conjugated with IGFBP-3 as a coating of titanium implants enhanced osteogenesis and the osseointegration of dental implants., Conclusions: This study demonstrated that IGFBP-3 could be applied as a therapeutic component in dental implants to promote the osseointegration of dental implants in patients with diabetes, which affects MGO levels., Competing Interests: No potential conflict of interest relevant to this article was reported., (Copyright © 2022. Korean Academy of Periodontology.)

The skeletal muscle in aged rats adapts rapidly following a period of exercise. This adaptation includes structural remodeling and biochemical changes such as an up-regulation of antioxidant enzymes, content of stress and heat shock proteins (HSPs). However, the associated molecular mechanisms mediating different types of exercise training-induced adaptations are not yet completely understood. Therefore, the purpose of this study was to investigate the effects of duration and frequency exercise on the expression of HSPs, antioxidant enzymes, and mitogen-activated protein kinase (MAPKs) in the skeletal muscles of aged rats. Young (3-month-old) and aged (20-month-old) male Sprague-Dawley rats were randomly assigned to 6 groups and extensor digitorum longus (EDL; fast twitch muscle fiber) and soleus (SOL; slow twitch muscle fiber) skeletal muscles were collected immediately. The expression pattern of HSPs in skeletal muscles was decreased in old groups compared with young groups. Especially, HSPs showed lower expression in SOL than EDL muscle. Interestingly, HSPs in aged rats was increased significantly after S1 (single long-duration; 1×30 min, 5 days/week for 6 weeks) and M1 types (multiple short-duration; 3×10 min·day(-1), 5 days·week(-1) for 6 weeks) than S2 (single long-duration; 1×30 min, 3 days/week for 6 weeks) and M2 (multiple short-duration; 3×10 min·day(-1), 3 days·week(-1) for 6 weeks) types of exercise training. Also, superoxide dismutase (SODs) showed similar expression as HSP did. On the contrary, the p-ERK and p-JNK were down regulated. In addition, p-p38 level in the SOL muscle was activated markedly in all exercise groups. These results demonstrate that increasing of HSP expression through duration and frequency exercise can lead to protection and training-induced adaptation against aging-induced structural weakness in skeletal muscles. Key pointsThe expression of heat shock proteins (HSPs) in aged rats was increased significantly after single long-duration (S1) and multiple short-duration (M1) types than S2 and M2 types of exercise training in soleus (SOL) skeletal muscles.Superoxide dismutase (SODs) showed similar expression as HSPs did. On the contrary, the p-ERK and p-JNK were down regulated. In addition, p-p38 level in the SOL muscle was activated markedly in all exercise groups.Induction of HSPs and SODs by high duration and frequency of exercise training such as S1 and M1 types with concomitant MAPKs pathway depending on the type of muscles.The frequency and duration of exercise training could affect the functional adaptation and protection against aging-induced structural weakness of skeletal muscles through changing expression of related molecules.

The aim of this study was to modify the surfaces of magnetic iron oxide nanoparticles (IOPs) with gelatin in order to reduce cytotoxicity and enhance cellular uptake. The gelatin-coated IOPs were characterized in terms of their functionalization, size, surface charge, morphology and crystalline structure using Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), dynamic light scattering (DLS), transmission electron microscopy (BIO-TEM) and x-ray diffraction (XRD) analysis. The cytotoxicity of the gelatin-coated IOPs to human fibroblasts was assessed using an MTT-assay and was compared with uncoated IOPs. Similarly, the cellular uptake of the coated and uncoated IOPs was visualized using BIO-TEM and quantified using inductively coupled plasma spectroscopy (ICPS). As shown by the Fourier emission scanning electron microscopy (FE-SEM) and viability test, the massive uptake of uncoated IOPs lead to reduced viability. However, gelatin coating lead to increased viability and slow uptake without any visible distortion to the cell morphology.

Porous metals are attractive due to its unique physical, mechanical, and new bone tissue ingrowth properties. In the present study, the production of highly porous Ti-6Al-4V parts by powder metallurgical technology and subsequently it's uses in in vitro bone tissue engineering is described. A space-holder method using carbamide with different particle size to produce parts with porosities between 35 and 70% were applied. The compressive strength and Young's modulus of porous Ti-6Al-4V were determined. Results indicated that stress and Young's modulus decrease with increasing porosity and pore size. The porous parts are characterized by scanning electron microscopy. Furthermore, study was to investigate the effects of three different porosities of porous Ti-6Al-4V (35, 50, and 70%) on proliferation, differentiation, and cell-matrix interaction of mouse osteoblast-like cells, MC-3T3. Results showed that the cell proliferation was significantly (p < 0.05) higher on 70% porous Ti-6Al-4V. However, synthesis of different types of extra cellular matrix proteins was also more abundant on 70% porous Ti-6Al-4V than 35 and 50% porous Ti-6Al-4V disk except some specific proteins. An increase in alkaline phosphate activity was significantly (p < 0.05) higher on 70 and 50% porous Ti-6Al-4V disk after 12 days of MC-3T3 cells incubation. Above all, results indicated that porosity (nearly 70%) of porous Ti-6Al-4V topography affects proliferation and differentiation of osteoblast-like MC-3T3 cells. The results showed that this novel process is a promise to fabricate porous biomaterials for bone implants.