Amelogenin Peptide Extract Increases Differentiation and Angiogenic and Local Factor Production and Inhibits Apoptosis in Human Osteoblasts

Enamel matrix derivative (EMD), a decellularized porcine extracellular matrix (ECM), is used clinically in periodontal tissue regeneration. Amelogenin, EMD’s principal component, spontaneously assembles into nanospheres in vivo, forming an ECM complex that releases proteolytically cleaved peptides. However, the role of amelogenin or amelogenin peptides in mediating osteoblast response to EMD is not clear. Human MG63 osteoblast-like cells or normal human osteoblasts were treated with recombinant human amelogenin or a 5 kDa tyrosine-rich amelogenin peptide (TRAP) isolated from EMD and the effect on osteogenesis, local factor production, and apoptosis assessed. Treated MG63 cells increased alkaline phosphatase specific activity and levels of osteocalcin, osteoprotegerin, prostaglandin E2, and active/latent TGF-β1, an effect sensitive to the effector and concentration. Primary osteoblasts exhibited similar, but less robust, effects. TRAP-rich 5 kDa peptides yielded more mineralization than rhAmelogenin in osteoblasts in vitro. Both amelogenin and 5 kDa peptides protected MG63s from chelerythrine-induced apoptosis. The data suggest that the 5 kDa TRAP-rich sequence is an active amelogenin peptide that regulates osteoblast differentiation and local factor production and prevents osteoblast apoptosis

Antibacterial composite membranes of polycaprolactone/gelatin loaded with zinc oxide nanoparticles for guided tissue regeneration

The bacterial colonization of absorbable membranes used for guided tissue regeneration (GTR), as well as their rapid degradation that can cause their rupture, are considered the major reasons for clinical failure. To address this, composite membranes of polycaprolactone (PCL) and gelatin (Gel) loaded with zinc oxide nanoparticles (ZnO-NPs; 1, 3 and 6 wt% relative to PCL content) were fabricated by electrospinning. To fabricate homogeneous fibrillar membranes, acetic acid was used as a sole common solvent to enhance the miscibility of PCL and Gel in the electrospinning solutions. The effects of ZnO-NPs in the physico-chemical, mechanical and in vitro biological properties of composite membranes were studied. The composite membranes showed adequate mechanical properties to offer a satisfactory clinical manipulation and an excellent conformability to the defect site while their degradation rate seemed to be appropriate to allow successful regeneration of periodontal defects. The presence of ZnO-NPs in the composite membranes significantly decreased the planktonic and the biofilm growth of the Staphylococcus aureus over time. Finally, the viability of human osteoblasts and human gingival fibroblasts exposed to the composite membranes with 1 and 3 wt% of ZnO-NPs indicated that those membranes are not expected to negatively influence the ability of periodontal cells to repopulate the defect site during GTR treatments. The results here obtained suggest that composite membranes of PCL and Gel loaded with ZnO-NPs have the potential to be used as structurally stable GTR membranes with local antibacterial properties intended for enhancing clinical treatments

Antibacterial activity of homeopathic medications lycopodium clavatum and arsenicum album against periodontal bacteria

There are several controversies regarding the efficacy of homeopathic substances; however, these remedies are used in many countries for the treatment of various pathological conditions. The purpose of this study was to evaluate the in vitro antibacterial activity of two homeopathic tinctures Arsenicum album (mineral extract) and Lycopodium clavatum (plant extract) on the periodontal bacteria Actinomyces israelii, Streptococcus sanguinis, Prevotella intermedia, Aggregatibacter actinomycetemcomitans and Phorphyromonas gingivalis (P. gingivalis). Materials and methods: Equal numbers of bacteria were seeded on agar plates containing enriched media with the homeopathic solutions at 1dH and 1cH dilutions. After 7 days of incubation under anaerobic conditions, colony forming units (CFUs) were counted. The antibacterial effect was calculated based on the total number of CFUs observed on non-tincture containing agar, and on the tincture containing plates. Results: No visible growth of any of the strains was observed on the plates containing Arsenicum album at any of the dilutions tested. In contrast, when Lycopodium clavatum at 1cH dilution was tested, only P. gingivalis was susceptible to this compound. Conclusions: The results suggest that the mineral extract tincture had a greater antibacterial activity than the plant extract tincture, also Lycopodium clavatum preparation could be an effective inhibitor of periodontal pathogens bacteria such as P. gingivalis.Las medicinas homeopáticas se encuentran rodeadas de controversias, principalmente por la falta de investigaciones científicas y modelos clínicos que demuestren su eficacia, sin embargo, estos remedios son utilizados en muchos países para el tratamiento de diversos padecimientos. El objetivo de esta investigación fue evaluar la actividad antimicrobiana in vitro de dos tinturas homeopáticas, el Arsenicum album (tintura de origen vegetal), y el Lycopodium clavatum (tintura de origen mineral) sobre las bacterias periodontales Actinomyces israelii, Streptococcus sanguinis, Prevotella intermedia, Aggregatibacter actinomycetemcomitans y Phorphyromonas gingivalis. Materiales y métodos: cantidades iguales de bacterias se sembraron en platos con agar y medio enriquecido con las tinturas homeopáticas, a dos diferentes diluciones 1dH y 1cH. Posteriormente, las unidades formadoras de colonias (CFU) se contaron después de 7 días de incubación bajo condiciones de anaerobiosis, tanto en los platos que contenían las tinturas, como en los platos control. Resultados: Para todas las cepas bacterianas utilizadas en el presente estudio, los platos con Arsenicum album, y Lycopodium clavatuma una dilución 1dH no mostraron crecimiento visible de CFU. En el caso de la tintura de Lycopodium clavatum, solamente la cepa de P. gingivalis mostró inhibición a una dilución de 1cH, por el contrario, el Arsenicumalbum mostró una inhibición de todas las cepas utilizadas a la misma dilución. Conclusiones: Los resultados del presente estudio sugieren que la tintura de origen mineral tiene una mayor actividad antibacterial, comparada con la tintura de origen vegetal. Además, la tintura de Lycopodium clavatumpuede considerarse como un inhibidor efectivo para bacterias periodontopatógenas como la P. gingivalis.Se necesita un mayor número de estudios in vitro e in vivo para validar estos resultados

Effects of atomic ordering of Zirconium oxide nanomodification on stem cell differentiation

The present study shows that the atomic ordering of ZrO2 thin films influences the osteoblastic differentiation of human mesenchymal stem cells (hMSCs). The amorphous ZrO2 film produced a better hMSCs response than the bare Ti surfaces, characterized by a higher production of osteoblastic markers, suggesting that amorphous ZrO2 coatings may enhance bone formation around implants. Slight differences were observed for the surface properties of amorphous and nanocrystalline ZrO2 thin films, being significant the larger barrier properties of the amorphous film

Electrospun polycaprolactone nanofibres decorated by drug loaded chitosan nano- reservoirs for antibacterial treatments

The main limitation of conventional antibiotic therapies concerns the low efficacy to fight bacteria attacks during long treatment times. In this context, the integrated use of electrofluidodynamics (EFDs)—basically electrospinning and electrospraying—may represent an interesting route for designing nanostructured platforms with controlled release to prevent the formation of bacterial biofilms in oral implant sites. They allow for the deposition of nanofibres and nanoparticles by different modes—i.e. sequential, simultaneous—for the fabrication of more efficacious systems in terms of degradation protection, pharmacokinetic control and drug distribution to the surrounding tissues. Herein, we will investigate EFDs processing modes and conditions to decorate polycaprolactone nanofibres surfaces by chitosan nano-reservoirs for the administration of Amoxicillin Trihydrate as an innovative antibacterial treatment of the periodontal pocket

Effect of Surface Roughness of Deciduous and Permanent Tooth Enamel on Bacterial Adhesion

The adhesion of some bacteria has been attributed to critical levels of roughness in hard tissues, which increases the risk of developing caries. The objective of this work was to assess the effect of deciduous and permanent tooth enamel surface roughness on bacterial adhesion. One hundred and eight samples of deciduous and permanent enamel were divided into two groups (n = 54). G1_DE deciduous enamel and G2_PE permanent enamel. The surface roughness was measured by profilometry and atomic force microscopy (AFM). Subsequently, the evaluation of bacterial adherence was carried out in triplicate by means of the XTT cell viability test. Additionally, bacterial adhesion was observed using scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). The average values of the micrometric roughness in both groups were similar; however, in the nanometric scale they presented significant differences. Additionally, the G1_DE group showed the highest amount of adhered S. mutans and S. sanguinis compared to the G2_EP group. Although the roughness of deciduous and permanent enamel showed contrasting results according to the evaluation technique (area and scale of analysis), bacterial adhesion was greater in deciduous enamel; hence, enamel roughness may not be a determining factor in the bacterial adhesion phenomenon

Control experiment.

Control experiment to illustrate that the extracts obtained from the uncoated and coated PP do not affect the bacteria host from the surrogate viruses. A. Bacterial mat using only culture media. B. Bacterial mat adding the extracts. C Representative image of the bacteria lysis using the surrogate viruses. (TIF)</p

Representative figures of bacterial growth on agar plates after 24 h on-contact with or without the AgCu nanolayer.

Representative figures of bacterial growth on agar plates after 24 h on-contact with or without the AgCu nanolayer.</p

Viral aerosol control.

Viral concentration (PFUs) quantified from the agar plates is almost the same as the initial viral suspension. (TIF)</p