Methods: The nanoparticles were characterized by X-ray diffraction (XRD) analysis, field emission scanning electron microscopy, energy dispersive X-ray fluorescence, transmission electron microscopy (TEM), vibrating sample magnetometry (VSM) and Fourier transform infrared spectroscopy.
Results: The XRD analysis indicated the presence of pure Fe3O4-NPs while the TEM images indicated that the Fe3O4-NPs are spherical with a diameter range between 3.21 and 2.22 nm. The VSM study demonstrated that the magnetic properties were enhanced with the decrease in the percentage of honey. In vitro viability evaluation of Fe3O4-NPs performed by using the MTT assay on the WEHI164 cells demonstrated no significant toxicity in higher concentration up to 140.0 ppm, which allows them to be used in some biological applications such as drug delivery.
Conclusion: The presented synthesis method can be used for the controlled synthesis of Fe3O4-NPs, which could be found to be important in applications in biotechnology, biosensor and biomedicine, magnetic resonance imaging and catalysis.
MATERIALS AND METHODS: The differentiation of fibroblast-like cells from SHED was carried out by using specific human recombinant connective tissue growth factor (CTGF). To characterize fibroblastic differentiation, the induced cells were subjected to morphological changes, proliferation rate, gene expression analysis using quantitative reverse transcription-polymerase chain reaction (qRT-PCR), flow cytometry, and immunofluorescence staining. The commercial primary human gingival fibroblasts served as positive control in this study.
RESULTS: The results from characterization analysis were compared with that of commercial cells to ensure that the cells differentiated from SHED were fibroblast-like cells. The results showed the inductive effect of CTGF for fibroblastic differentiation in SHED. SHED-derived fibroblasts were successfully characterized despite having similar morphological appearance, i.e., (i) significant proliferation rate between fibroblast-like cells and SHED, (ii) high expression of fibroblast-associated markers in qRT-PCR analysis, and (iii) positive staining against collagen type 1, fibroblast-specific protein 1, and human thymic fibroblasts in flow cytometry analysis and immunofluorescence staining. The same expression patterns were found in primary human gingival fibroblasts, respectively. SHED as negative control showed lower expression or no signal, thus confirming the cells differentiated from SHED were fibroblast-like cells.
CONCLUSIONS: Taken together, the protocol adopted in this study suggests CTGF to be an appropriate inducer in the differentiation of SHED into fibroblast-like cells.
CLINICAL RELEVANCE: The fibroblast-like cells differentiated from SHED could be used in future in vitro and in vivo dental tissue regeneration studies as well as in clinical applications where these cells are needed.
OBJECTIVE: This study aimed to determine the potential of ascorbic acid alone in inducing differentially expressed osteoblast-related proteins in dental stem cells via the liquid chromatography-mass spectrometry/ mass spectrometry (LC-MS/MS) approach.
METHODS: The cells were isolated from deciduous (SHED) and permanent teeth (DPSC) and induced with 10 μg/mL of ascorbic acid. Bone mineralisation and osteoblast gene expression were determined using von Kossa staining and reverse transcriptase-polymerase chain reaction. The label-free protein samples were harvested on days 7 and 21, followed by protein identification and quantification using LC-MS/MS. Based on the similar protein expressed throughout treatment and controls for SHED and DPSC, overall biological processes followed by osteoblast-related protein abundance were determined using the PANTHER database. STRING database was performed to determine differentially expressed proteins as candidates for SHED and DPSC during osteoblast development.
RESULTS: Both cells indicated brownish mineral stain and expression of osteoblast-related genes on day 21. Overall, a total of 700 proteins were similar among all treatments on days 7 and 21, with 482 proteins appearing in the PANTHER database. Osteoblast-related protein abundance indicated 31 and 14 proteins related to SHED and DPSC, respectively. Further analysis by the STRING database identified only 22 and 11 proteins from the respective group. Differential expressed analysis of similar proteins from these two groups revealed ACTN4 and ACTN1 as proteins involved in both SHED and DPSC. In addition, three (PSMD11/RPN11, PLS3, and CLIC1) and one (SYNCRIP) protein were differentially expressed specifically for SHED and DPSC, respectively.
CONCLUSION: Proteome differential expression showed that ascorbic acid alone could induce osteoblastrelated proteins in SHED and DPSC and generate specific differentially expressed protein markers.