Objective To clarify the effects of Xinfukang containing-serum on stromal cell-derived factor-1α (SDF-1α) translation and protein secretion of bone marrow stem cells (BMSCs).Methods BMSCs were isolated and amplified using bone marrow culture method,and were identified by flow cytometry.mRNA and protein secretion of SDF-1α were detected by quantitative PCR (q-PCR) and enzyme linked immunosorbent assay (ELISA),respectively.Results The expression of SDF-1α mRNA were significantly increased after 72 h in drug-containing serum,and SDF-1α mRNA in the experimental group was approximately 200 times as that in the control group (P＜0.05).Secretion of SDF-1 α in the experimental group (277.561 1 ± 15.651 8) pg/ml was nearly doubled compared with that in the control group (153.107 1±14.765 1) pg/ml (P＜0.05).Conclusions BMSCs from whole bone marrow adherent culture have high purity,and drug-containing serum can promote BMSCs to express SDF-1 α mRNA and secretion of SDF-1 α.

Objective:To investigate the biocompatibility of coral-like barium titanate nano-piezoelectric coatings and the influence of ultrasound-excited piezoelectric effect on the early osteogenic differentiation.Methods:The barium titanate nano-piezoelectric coating (the coating group) was prepared on the surface of titanium metal by anodic oxidation, hydrothermal reaction and high-temperature annealing, and polished titanium specimens were used as control group. The surface morphology, composition, and crystal phase and hydrophilicity of the two groups of titanium specimens were characterized using scanning electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy and contact angle meter. The piezoelectric properties of the materials were characterized by piezoresponse force microscopy. Rat bone marrow mesenchymal stem cells (BMSC) were cultured and identified and seeded the surface of titanium specimens in two groups. The cells seeded on blank culture plates were used as blank group. After low intensity pulsed ultrasound intervention, cell proliferation and live/dead staining were detected to evaluate cytocompatibility of the coatings. Alkaline phosphatase (ALP) activity of each group was detected by ALP staining kit, and the expression of osteogenesis-related genes [integrin, bone morphogenetic protein 2 (BMP-2), Runt-related transcription factor 2 (RUNX2)] was detected by real-time fluorescent quantitative PCR (RT-qPCR) to evaluate the effect of the coating on promoting the early osteogenic differentiation of BMSC.Results:The surface of titanium specimens in the coating group showed a uniform coral-like morphology, and the diameter of the coral tentacles was 70-100 nm. The main component was tetragonal barium titanate. The surface hydrophilicity of the coating group (water contact angle 10.12°± 0.93°) was significantly better than that of the control group (water contact angle 78.32°±0.71°) ( F= 10 165.91, P<0.001). The coating has a stable piezoelectric property with a piezoelectric constant of about 5 pC/N. Cell experiments showed that, with or without ultrasound, the cell proliferation activity of the coating group was significantly lower than that of the blank group and the control group on the third day ( P<0.05). On the fifth day, with or without ultrasound, there was no significant difference in cell proliferation activity between the three groups ( P>0.05). After 7 days of culture, the ALP activity of the coating group was significantly higher than that of the blank group and the control group ( P<0.05). The results of RT-qPCR showed that the mRNA expression of integrin and BMP-2 in the coating group with ultrasound was significantly higher than that in the other groups with ultrasound, and was higher than that of the coating group without ultrasound ( P<0.05). The expression of integrin mRNA in the control group with ultrasound was significantly higher than that in the control group without ultrasound ( P<0.05). The expression of RUNX2 mRNA in the coating group with ultrasound was significantly higher than that in the coating group without ultrasound ( P<0.05). Conclusions:The coral-like barium titanate nano-piezoelectric coating exhibits favorable biocompatibility and stable piezoelectric property, and facilitates the early osteogenic differentiation of BMSC under the excitation of low-intensity pulsed ultrasound.

In recent years, mesenchymal stem cell-derived exosomes (MSC-EXO) have garnered increasing attention in the field of stomatology and have become an established research area in biomedical research. This article reviews the engineering of exosomes derived from mesenchymal stem cells and their application in the field of stomatology, in order to provide new ideas for the development of stomatology. Exosomes are nanoscale membrane vesicles secreted by cells and contain a variety of proteins, RNAs, lipids, and other biomolecules. They are transported through the circulatory system and can interact with other cells to regulate their biological behavior and participate in a variety of physiological and pathological processes. In the treatment of oral diseases, exosomes have shown great potential due to their natural biological activity and versatility. However, studies have found that relying solely on the function of natural exosomes may not fully meet the complex clinical requirements. Therefore, the concept of engineered exosomes has emerged. Engineered exosomes can be modified by bioengineering technology to enhance their targeting, allowing them to reach the lesion site more accurately. At the same time, engineered exosomes can also be surface modified or loaded internally to carry specific therapeutic molecules, such as drugs, gene editing tools or signaling molecules to improve the therapeutic effect. In addition, this engineered treatment can also confer greater stability to exosomes, making them better able to resist clearance by the immune system when circulating in the body, extending their half-life, and improving the effectiveness of treatment. Although engineered exosomes have attracted extensive attention in the fields of stomatology and other fields, their application is still mainly in the stage of basic research. To promote the clinical application of engineered exosomes, it is necessary to provide more sufficient evidence of biocompatibility and clarify their therapeutic effect and mechanism.