No abstract

Ficus deltoidea (Mas cotek) water extract has been widely used for woman health in Malaysia. Our investigation focused to identify anti-melanogenic efficacy of F. deltoidea since it has been known to have strong anti-oxidant activities. Anti-melanogenic effect of F. deltoidea extract was analyzed using cultured B16F1 melanoma cells. Cytotoxicity of the extract was measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and determined the highest concentration of the extract that did not affect cell viability as 0.1% (w/v). α-MSH-induced melanin synthesis was significantly inhibited with dose-dependent manner by treatment of F. deltoidea leave extract, which was comparable to that of kojic acid. The extract directly inhibited mushroom tyrosinase activity and intracellular tyrosinase activity of B16F1 as well. The inhibition of intracellular tyrosinase activity was found to be exerted at the protein expression level when analyzed by immunoblot and tyrosinase zymography. The expression of microphthalmia-associated transcription factor (MITF) was also reduced by the F. deltoidea extract. In conclusion, F. deltoidea extract has strong anti-melanogenic activity that is exerted by direct inhibition of tyrosinase enzyme activity and by down-regulation of the expression of genes involved in the melanogenesis pathways. Collectively, data shown in this study strongly suggest that F. deltoidea extract has potential to be used as a novel depigmenting agent for cosmetics.

We made an artificial skin comprised of a stratified layer of keratinocytes and a dermal matrix with a type I collagen containing fibroblasts. In this work, we showed keratinocyte behavior under primary culture, gel contractions varying with concentration of collagen solution, and cell growth plots in the collagen gel. The optimum behavior of dermal equivalent could be obtained using 3.0 mg/ml collagen solution and attached gel culture. The attached gel culture had a jumping effect of growth factor on cell growth at the lag phase. To develop the artificial skin, 1x10(5) cells/cm2 of keratinocytes were cultured on the dermal equivalent at air-liquid interface. Finally, to overcome the problem that artificial skin of collagen gel was torn easily during suturing of grafting, we prepared histocompatible collagen mesh and attached the mesh to the bottom of the gel. Cultured artificial skins were successfully grafted onto rats.

We evaluated the new bone regeneration of a rabbit mandibular defect using hBMSCs under electrical stimulation combined with rhBMP-2 in this study. An inner scaffold prepared by setting a collagen sponge with hBMSCs and hydrogel was placed into a polycaprolactone (PCL) outer box, and an electrical stimulation device was installed between the inner scaffold and the outer box. There were three experimental groups depending on electrical stimulation and application of rhBMP-2. The experimental group was divided into the following three groups. Group 1, in which rhBMP-2 (5 μg/defect) was added to hydrogel and electrical stimulation was not applied; Group 2, in which rhBMP-2 (5 μg/defect) was added as in Group 1 and electrical stimulation was applied; and Group 3, in which electrical stimulation was applied and rhBMP-2 (5 μg/defect) was injected directly into defect site. The delivered electrical stimulation was charge-balanced bi-phasic electric current pulses, and electrical stimulation was conducted for 7 days. The stimulation parameters of the bi-phasic electrical current set at an amplitude of 20 μA, a duration of 100 μs and a frequency of 100 Hz. Four weeks after surgery, new bone formation in each group was evaluated using radiography, histology, and micro-computed tomography (μCT). Groups 2 and 3 exhibited a significant increase in new bone formation compared to Group 1, while Group 3 showed the highest level of new bone regeneration. In a comparison between two groups, Group 2 showed a higher bone volume (BV) by 260 % (p < 0.01) compared with Group 1, and Group 3 showed a higher BV by 442 % (p < 0.01) compared with Group 1. The trend of the bone surface density (ratio of new bone to the real defect volume, BS/TV), trabecular number, and connectivity was identical to that of the BV. The total bone mineral density (BMD) of Groups 2 and 3 showed values higher by the ratios of 103 % (p < 0.01) and 107.5 % (p < 0.01) compared with Group 1, respectively. Part BMD for Groups 2 and 3 showed higher values by the ratios of 104.9 % (p < 0.01) and 122.4 % (p < 0.01) compared with Group 1, respectively. These results suggest that the combined treatment of electrical stimulation, hBMSCs, a collagen sponge, hydrogel, and rhBMP-2 was effective for bone regeneration of large-size mandibular defects. The application of rhBMP-2 with an injection following electrical stimulation demonstrated better efficiency as regards bone regeneration.

The aim of this study was to compare the cell compatibility of silk and polyglycolic acid (PGA) scaffolds cultured in vitro with mesenchymal stem cells (MSCs) and peripheral blood mononuclear cells (PBMCs) to their biocompatibility in vivo following implantation. Scaffolds were knitted with silk or PGA thread and the average efficiency of cell attachment was 35 +/- 4% and 17 +/- 2% in the PGA and silk scaffold groups. Thus, the initial attachment of the MSC cells to the PGA scaffold was superior to the initial attachment of the cells on the silk scaffold. After 21 days in culture, the average cell density on the silk scaffold was 5.8 +/- 0.5 x 10(5) cells, and the average cell density of the PGA scaffolds was 6.34 +/- 0.5 x 10(5) cells. In addition, there was no cell cytoxicity observed with either scaffold. However, the immune response of in vitro cultured PBMCs was significantly higher with the PGA scaffold than with the silk scaffold. The proliferation of the PBMCs cultured on the PGA scaffold was two times greater than that of those cultured on the silk scaffold after 3 days of culture. In addition, the secretion of IL-1 by the PBMCs cultured on the PGA scaffold was superior to that of the PBMCs cultured on the silk scaffold. The secretion of IL-1beta and IFN-gamma was increased by about 50% when the PBMCs were cultured with the PGA scaffold. Silk and PGA scaffolds were also implanted subcutaneous in rats. Histological evaluation of the scaffold explants revealed the presence of monocytes and macrophages in PGA scaffold. The inflammatory tissue reaction was more conspicuous on the PGA scaffold than on the silk scaffold. These results suggest that the results of in vitro PBMC cultures were more closely related to the in vivo results of implantation than the results of in vitro MSC cultures.