Enhancement of Osteoblast Differentiation Using No-Ozone Cold Plasma on Human Periodontal Ligament Cells.

Periodontitis is an inflammatory disease that leads to periodontal tissue destruction and bone resorption. Proliferation and differentiation of cells capable of differentiating into osteoblasts is important for reconstructing periodontal tissues destroyed by periodontitis. In this study, the effects of the nozone (no-ozone) cold plasma (NCP) treatment on osteoblastic differentiation in periodontal ligament (PDL) cells were investigated. To test the toxicity of NCP on PDL cells, various NCP treatment methods and durations were tested, and time-dependent cell proliferation was analyzed using a water-soluble tetrazolium salts-1 assay. To determine the effect of NCP on PDL cell differentiation, the cells were provided with osteogenic media immediately after an NCP treatment to induce differentiation; the cells were then analyzed using alkaline phosphatase (ALP) staining, an ALP activity assay, real time PCR, and Alizarin Red S staining. The NCP treatment without toxicity on PDL cells was the condition of 1-min NCP treatment immediately followed by the replacement with fresh media. NCP increased ALP, osteocalcin, osteonectin, and osteopontin expression, as well as mineralization nodule formation. NCP treatment promotes osteoblastic differentiation of PDL cells; therefore, it may be beneficial for treating periodontitis.

The effect of biomechanical stimulation on osteoblast differentiation of human jaw periosteum-derived stem cells.

BACKGROUND: This study was to investigate the effect of biomechanical stimulation on osteoblast differentiation of human periosteal-derived stem cell using the newly developed bioreactor. METHODS: Human periosteal-derived stem cells were harvested from the mandible during the extraction of an impacted third molar. Using the new bioreactor, 4% cyclic equibiaxial tension force (0.5 Hz) was applied for 2 and 8 h on the stem cells and cultured for 3, 7, and 14 days on the osteogenic medium. Biochemical changes of the osteoblasts after the biomechanical stimulation were investigated. No treatment group was referred to as control group. RESULTS: Alkaline phosphatase (ALP) activity and ALP messenger RNA (mRNA) expression level were higher in the strain group than those in the control group. The osteocalcin and osteonectin mRNA expressions were higher in the strain group compared to those in the control group on days 7 and 14. The vascular endothelial growth factor (VEGF) mRNA expression was higher in the strain group in comparison to that in the control group. Concentration of alizarin red S corresponding to calcium content was higher in the strain group than in the control group. CONCLUSIONS: The study suggests that cyclic tension force could influence the osteoblast differentiation of periosteal-derived stem cells under optimal stimulation condition and the force could be applicable for tissue engineering.

Targeting NEU Protein in Melanoma Cells with Non-Thermal Atmospheric Pressure Plasma and Gold Nanoparticles.

Non-thermal atmospheric pressure plasma effectively kills cancer cells, but it cannot selectively kill cancer cells. The authors targeted NEU (human epidermal growth factor receptor 2) protein, which is frequently over-expressed in the cell membrane of melanoma cells, using anti-NEU antibody-labeled gold nanoparticles. The labeled nanoparticles preferentially targeted melanoma cells rather than normal keratinocytes. After the addition of labeled gold nanoparticles to melanoma and normal keratinocyte cells, both cells were exposed to non-thermal atmospheric pressure plasma. The death rate of melanoma cells was significantly higher than that of normal keratinocyte cells; many vacuoles, indicative of cell death, were observed in melanoma cells treated with anti-NEU antibody labeled gold nanoparticles and plasma. This selective cancer cell death was attributed to the selective destruction of NEU protein and a downstream effector of NEU. Our study findings show that treatment with a combination of non-thermal atmospheric pressure plasma and anti-NEU antibody-labeled gold nanoparticles effectively and selectively kills melanoma cells.

Scutellariae radix induces apoptosis in chemoresistant SCC-25 human tongue squamous carcinoma cells.

Scutellariae radix is one of the most widely used anticancer herbal medicines in several Asian countries, including Korea, Japan, and China. Squamous cell carcinoma (SCC) is one of the most common head and neck carcinomas, which is highly invasive and metastatic, and can potentially develop chemoresistance. Therefore, new effective treatment methods are urgently needed. We determined the effects of Scutellariae radix on SCC-25 cells using the WST-1 assay, F-actin staining, flow cytometry analysis, immunofluorescence staining, and western blot analysis. Scutellariae radix treatment inhibited SCC-25 cell growth in a dose- and time-dependent manner, but it did not inhibit HaCaT (human keratinocyte) cell growth. Changes in cell morphology and disruption of filamentous (F)-actin organization were observed. Scutellariae radix-induced apoptosis as indicated by the translocation of cytochrome c and apoptosis-inducing factor (AIF) into the nucleus and cytosol. Scutellariae radix-induced an increase in cells with sub-G1 DNA content, and increased Bax, cleaved caspase-3, caspase-7, caspase-9, DNA fragmentation factor 45 (DFF 45), and poly(ADP-ribose) polymerase-1 (PARP-1) expression levels. Furthermore, increased expression of phosphorylated mitogen-activated protein kinase (MAPK)-related proteins was detected. The antitumor effect of Scutellariae radix was due to decreased cell proliferation, changes in cell morphology, and the activation of caspase and MAPK pathways. Taken together, the findings of this study highlight the anticancer activity of Scutellariae radix in chemoresistant SCC-25 oral squamous carcinoma cells.

Enhancement of the killing effect of low-temperature plasma on Streptococcus mutans by combined treatment with gold nanoparticles.

BACKGROUND: Recently, non-thermal atmospheric pressure plasma sources have been used for biomedical applications such as sterilization, cancer treatment, blood coagulation, and wound healing. Gold nanoparticles (gNPs) have unique optical properties and are useful for biomedical applications. Although low-temperature plasma has been shown to be effective in killing oral bacteria on agar plates, its bactericidal effect is negligible on the tooth surface. Therefore, we used 30-nm gNPs to enhance the killing effect of low-temperature plasma on human teeth. RESULTS: We tested the sterilizing effect of low-temperature plasma on Streptococcus mutans (S. mutans) strains. The survival rate was assessed by bacterial viability stains and colony-forming unit counts. Low-temperature plasma treatment alone was effective in killing S. mutans on slide glasses, as shown by the 5-log decrease in viability. However, plasma treatment of bacteria spotted onto tooth surface exhibited a 3-log reduction in viability. After gNPs were added to S. mutans, plasma treatment caused a 5-log reduction in viability, while gNPs alone did not show any bactericidal effect. The morphological changes in S. mutans caused by plasma treatment were examined by transmission electron microscopy, which showed that plasma treatment only perforated the cell walls, while the combination treatment with plasma and gold nanoparticles caused significant cell rupture, causing loss of intracellular components from many cells. CONCLUSIONS: This study demonstrates that low-temperature plasma treatment is effective in killing S. mutans and that its killing effect is further enhanced when used in combination with gNPs.