Proliferation Of Mesenchymal Cells Research Articles

Thermodynamic 2D Silicene for Sequential and Multistage Bone Regeneration.

Bone healing is a multistage process involving the recruitment of cells, revascularization, and osteogenic differentiation, all of which are modulated in the temporal sequence to maximize cascade bone regeneration. However, insufficient osteoblast cells, poor blood supply, and limited bone induction at the site of critical-sized bone defect broadly impede bone repair. 2D SiO2 -silicene@2,2'-,azobis(2-[2-imidazolin-2-yl] propane) (SNSs@AIPH) with inherent thermodynamic property and osteoinductive activity is therefore designed and engineered for sequentially efficient bone repair. By means of controllable NIR-II irradiation, the integrated SNSs@AIPH stimulates the generation of appropriate intracellular reactive oxygen species, which accelerates early bone marrow mesenchymal stem cells (BMSCs) proliferation and angiogenesis remarkably. Importantly, as silicon-based 2D nanoparticles, the engineered SNSs@AIPH with high biocompatibility features distinct bioactivity to significantly promote BMSCs osteogenesis differentiation by activating TGFβ and BMP pathways. In a rat cranial defect model, SNSs@AIPH-NIR-II leads to a comparable increase of BMSCs proliferation and local vascularization at an early stage, followed by significant osteogenic differentiation, synergically resulting in a highly effective bone repair. Collectively, the fascinating characteristics and exceptional bone repair efficiency of NIR-II-mediated SNSs@AIPH allow it to be a promising bionic-oriented strategy for bone regeneration, broadening a new perspective in the application of cell-instructive biomaterials in bone tissue engineering.

The Influence of Zoledronic Acid on the Proliferation and Osteogenic Differentiation of Bone Marrow Mesenchymal Stem Cells and Tibial Fracture in Rats via Phosphatidylinositol-3-Kinase/AKT Pathway

Fracture healing is an extremely complex physiological process, involving a sequence of crucial mechanisms. Whether zoledronic acid (ZA) affects proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) and tibial fractures still remains unknown. We performed construction of the tibial fracture model in rats and analyzed the impact of ZA and ZA+LY294002 on fracture healing in rats. Test of the influence of ZA and ZA+LY294002 on crucial osteogenic genes alkaline phosphatase (ALP), RUNX2, OCN and OPN was performed. Examination of the influence of suppressing the PI3K/AKT pathway on the proliferation with bone differentiation of ZA. Results showed ZA distinctly accelerated the proliferation and ALP activity of BMSC cells, BMP2, RUNX2, OCN, OPN and the activation of the PI3K/AKT pathway. Repression of PI3K/AKT pathway suppressed the proliferation and osteogenic differentiation action of ZA. ZA boosted tibial fracture healing in rats via activating the PI3K/AKT pathway. ZA facilitates the proliferation with osteogenic differentiation of BMSC cells and tibial fracture healing in rats via activating the PI3K/AKT pathway.

M2 macrophages-derived exosomes combined with acellular cartilage matrix scaffolds promote osteochondral regeneration via modulatory microenvironment

Articular cartilage (AC) regeneration has always been a difficult problem for clinicians. Anti-inflammatory (M2) macrophages have anti-inflammatory and tissue repair effects. Exosomes are reported to have multiple complicated biological functions. It has been shown that M2 macrophages-derived exosomes (M2D-Exo) can influence the course of certain diseases, but their effect on the repair of cartilage defects has not been reported. The aim of this study was to verify whether M2D-Exo could enhance the repair of acellular cartilage extracellular matrix (ACECM) scaffolds. Here, we characterized the ACECM scaffolds and identified the M2D-Exo by transmission electron microscopy (TEM), Western blotting (WB), and nanoparticle tracking analysis (NTA). In vitro, the results showed that M2D-Exo could promote the migration, proliferation and chondrogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs). It was also found that M2D-Exo could reduce the expression of proinflammatory factors and promote M2 polarization, which ultimately protected chondrocytes and inhibited chondrocyte apoptosis. In vivo results confirmed that M2D-Exo could promote the repair effect of ACECM scaffolds, promote osteochondral regeneration and regulate the joint cavity inflammatory microenvironment. In conclusion, this study confirms that M2D-Exo can be used as a new therapeutic strategy for osteochondral regenerative repair.

Effects of Homeopathic Remedies on Mesenchymal Stem Cell Proliferation: A Methodology Study

Background and purpose: Mesenchymal stem cells are multipotent cells of mesodermal origin,
 which have the ability to differentiate into other cells in the bone marrow microenvironment under
 suitable conditions in vitro. Homeopathy is a holistic practice method that aims to improve health
 status with personalized homeopathic medicines. At the same time, it is among the certified training
 programs of the Traditional and Complementary Medicine Practices of the Ministry of Health. Studies
 evaluating the effect of homeopathic remedies in the field of stem cells are rarely encountered in the
 literature. As a matter of fact, the material and method parts of these studies are not clear enough. In
 our study, the methodology of working with mesenchymal stem cells of homeopathic remedies has
 been presented in detail and it has been aimed to observe their proliferative effects.
 
 Material and Methods: Mesenchymal stem cells were exposed to 10%, 20%, 50% and 100% ratios
 of homeopathic remedies (30°C potency: Aloe, Calendula, Hypericum, Staphysagria) for 24 and 48
 hours. The percent viability of cells at 24 and 48 hours was evaluated with the MTT (3-4,5-dimethyl-
 thiazolyl-2,5-diphenyltetrazolium bromide) test.
 
 Results: Aloe vera C 30 – Staphysagria C30 – Calencula C30 – Hypericum C30 remedies were found
 to have an effect on mesenchymal stem cell proliferation at all doses, and the results were statistically
 more significant when maintained in 10% media.
 
 Conclusion: It is thought that the methodology used in this study on working methods with
 homeopathic remedies will contribute to the literature and many scientific studies to be done in the
 future.

Design, development and characterisation of an optimised scaffold to enhance cell proliferation for tissue repair

Scaffolds are implanted to spur the regeneration of damaged tissues. The inappropriate construction of scaffolds laden with cells is not efficient. The optimisation of the scaffolds’ constituents is essential for tissue repair. In this study, a scaffold embedded with Raloxifene drug was optimised via Response Surface Methodology (RSM), targeting controlled cell proliferation. The independent variables for RSM (fibronectin, collagen I, glutaraldehyde, and Raloxifene) were screened in Swiss target prediction software (probability ≥99%) to optimise dependent variables (porosity, cell viability, degradation, and swelling) by ANOVA and characterised with FTIR, SEM and contact angle measurement. The scaffold was tested for antimicrobial property, and proliferation and attachment of mouse mesenchymal stem cells. The ANOVA analysis with p value ≤ 0.0001 suggested the optimal concentration of biomaterials and drugs. The optimised scaffold displayed 80% porosity with pore size 33 ± 3 µm. We also observed significant cell attachment and proliferation (p value ≤ 0.05) in optimised scaffold. The scaffold may be further evaluated for its potential for tissue repair.

Better isolation, proliferation and differentiation of human adipose-derived mesenchymal stem cells using human serum.

Mesenchymal stem cells have many applications in medicine. Attention to the proliferation and differentiation of stem cell differentiation is an important issue. The aim of this study was to investigate the possibility of optimal isolation, proliferation, and differentiation of adipose tissue-derived mesenchymal stem cells (ADSCs) using human serum. Human serum (HS) was obtained from the venous blood of eight healthy individuals. The rate of proliferation and differentiation of ADSCs and expression of surface markers was assessed by flow cytometry. Bone differentiation was assessed using Alizarin Red staining. Data were analyzed using statistical software. Over time, HS showed more proliferation than fetal bovine serum (FBS) -enriched cells (p <0.05). Differentiation of ADSCs cells ls in HS-enriched medium is faster and more pronounced than differentiation in the control group. The expression of surface markers in the medium containing HS was the same as the medium containing FBS where the expression levels of CD105 and CD95 were found to be positive and the expression of CD34 and CD45 was negative. Due to the better proliferation of adipose tissue-derived mesenchymal cells in the medium containing HS than FBS, it is suggested that human serum be used in future clinical studies. Also, HS is healthier, safer, more accessible, and more affordable than FBS.

Influence of porosity on osteogenesis, bone growth and osteointegration in trabecular tantalum scaffolds fabricated by additive manufacturing.

Porous tantalum implants are a class of materials commonly used in clinical practice to repair bone defects. However, the cumbersome and problematic preparation procedure have limited their widespread application. Additive manufacturing has revolutionized the design and process of orthopedic implants, but the pore architecture feature of porous tantalum scaffolds prepared from additive materials for optimal osseointegration are unclear, particularly the influence of porosity. We prepared trabecular bone-mimicking tantalum scaffolds with three different porosities (60%, 70% and 80%) using the laser powder bed fusing technique to examine and compare the effects of adhesion, proliferation and osteogenic differentiation capacity of rat mesenchymal stem cells on the scaffolds in vitro. The in vivo bone ingrowth and osseointegration effects of each scaffold were analyzed in a rat femoral bone defect model. Three porous tantalum scaffolds were successfully prepared and characterized. In vitro studies showed that scaffolds with 70% and 80% porosity had a better ability to osteogenic proliferation and differentiation than scaffolds with 60% porosity. In vivo studies further confirmed that tantalum scaffolds with the 70% and 80% porosity had a better ability for bone ingrowh than the scaffold with 60% porosity. As for osseointegration, more bone was bound to the material in the scaffold with 70% porosity, suggesting that the 3D printed trabecular tantalum scaffold with 70% porosity could be the optimal choice for subsequent implant design, which we will further confirm in a large animal preclinical model for better clinical use.

Synthesis, Characterization, In Vitro Cytological Responses, and In Vivo Bone Regeneration Effects of Low-Crystalline Nanocarbonated Hydroxyapatite.

Hydroxyapatite (HA) has been commonly used as an alternative bone substitute. But it has drawbacks, such as poor degradation and limited osteogenesis. Low-crystalline carbonated hydroxyapatite (L-CHA), which has greater biodegradability than HA, is suggested as one of the main components of bone minerals, but the exact mechanism behind the roles of carbonate substituted in biological behaviors of low-crystalline HA is still a mystery. In this study, L-CHAs with different carbonate contents were prepared, and the effects of the content on the physicochemical properties, in vitro cytological responses, and in vivo bone defects repair effects of L-CHAs were investigated. The results demonstrated that CO32- had successfully entered the lattice structure of L-CHAs with a maximum content of 9.2 wt %. Both low-crystalline undoped HA (L-HA) and L-CHAs were nanocrystalline (20-30 nm) with significantly higher specific surface areas, protein adsorption capacities, and biodegradability compared to high-crystalline HA (H-HA) with submicron crystalline size (200-400 nm). Besides, the amounts of the adsorbed protein and released Ca2+ ions increased in a carbonate-content-dependent manner. Compared to L-HA and H-HA, L-CHAs promoted the adhesion and proliferation of bone marrow mesenchymal stem cells and significantly upregulated the levels of alkaline phosphatase (ALP) activity and the expression of osteogenesis-related genes. In addition, L-CHA-9 not only showed a faster biodegradation rate but also effectively promoted bone regeneration when implanted in the critical-sized bone defects of rabbit femora. This study provided evidence for the development of L-CHA as a promising biodegradable and bioactive material with great osteoconductivity and osteogenic capability with respect to conventional HA.

Amorphizing Metal Selenides-Based ROS Biocatalysts at Surface Nanolayer toward Ultrafast Inflammatory Diabetic Wound Healing.

The microenvironments with high reactive-oxygen-species (ROS) levels, inflammatory responses, and oxidative-stress effects in diabetic ulcer wounds, leading to poor proliferation and differentiation of stem cells, severely inhibit their efficient healing. Here, to overcome the unbalanced multielectron reactions in ROS catalysis, we develop a cobalt selenide-based biocatalyst with an amorphous Ru@CoSe nanolayer for ultrafast and broad-spectrum catalytic ROS-elimination. Owing to the enriched electrons and more unoccupied orbitals of Ru atoms, the amorphous Ru@CoSe nanolayer-equipped biocatalyst displays excellent catalase-like kinetics (maximal reaction velocity, 23.05 μM s-1; turnover number, 2.00 s-1), which exceeds most of the currently reported metal compounds. The theoretical studies show that Ru atoms act as "regulators" to tune the electronic state of the Co sites and modulate the interaction of oxygen intermediates, thus improving the reversible redox properties of active sites. Consequently, the Ru@CoSe can efficiently rescue the proliferation of mesenchymal stem cells and maintain their angiogenic potential in the oxidative stress environment. In vivo experiments reveal the superior ROS-elimination ability of Ru@CoSe on the inflammatory diabetic wound. This study offers an effective nanomedicine for catalytic ROS-scavenging and ultrafast healing of inflammatory wounds and also provides a strategy to design biocatalytic metal compounds via bringing amorphous catalytic structures.

Co-Surfactant-Free Bioactive Protein Nanosheets for the Stabilization of Bioemulsions Enabling Adherent Cell Expansion.

Bioemulsions are attractive platforms for the scalable expansion of adherent cells and stem cells. In these systems, cell adhesion is enabled by the assembly of protein nanosheets that display high interfacial shear moduli and elasticity. However, to date, most successful systems reported to support cell adhesion at liquid substrates have been based on coassemblies of protein and reactive cosurfactants, which limit the translation of bioemulsions. In this report, we describe the design of protein nanosheets based on two globular proteins, bovine serum albumin (BSA) and β-lactoglobulin (BLG), biofunctionalized with RGDSP peptides to enable cell adhesion. The interfacial mechanics of BSA and BLG assemblies at fluorinated liquid-water interfaces is studied by interfacial shear rheology, with and without cosurfactant acyl chloride. Conformational changes associated with globular protein assembly are studied by circular dichroism and protein densities at fluorinated interfaces are evaluated via surface plasmon resonance. Biofunctionalization mediated by sulfo-succinimidyl 4-(N-maleimidomethyl) cyclohexane-1-carboxylate (sulfo-SMCC) is studied by fluorescence microscopy. On the basis of the relatively high elasticities observed in the case of BLG nanosheets, even in the absence of cosurfactant, the adhesion and proliferation of mesenchymal stem cells and human embryonic kidney (HEK) cells on bioemulsions stabilized by RGD-functionalized protein nanosheets is studied. To account for the high cell spreading and proliferation observed at these interfaces, despite initial moderate interfacial elasticities, the deposition of fibronectin fibers at the surface of corresponding microdroplets is characterized by immunostaining and confocal microscopy. These results demonstrate the feasibility of achieving high cell proliferation on bioemulsions with protein nanosheets assembled without cosurfactants and establish strategies for rational design of scaffolding proteins enabling the stabilization of interfaces with strong shear mechanics and elasticity, as well as bioactive and cell adhesive properties. Such protein nanosheets and bioemulsions are proposed to enable the development of new generations of bioreactors for the scale up of cell manufacturing.

The Biocompatibility and Antibacterial Properties of the CNTs-Doped Magnesium Based Composite Implants in a Long-Term Biodegradation Process

The aim of this paper is to increase a new biodegradable implant material’s biodegradability, biocompatibility, and osteoinductivity in the long-term degradation process, as well as its antibacterial properties, novel carbon nanotubes (CNTs) with or without Cu element were doped into calcium phosphate (CaP)–chitosan (CS) layers and then fabricated to obtain the magnesium (Mg) matrix composites. In this paper, we investigated the influences of the CNTs-CaP-CS/Mg composites on proliferation and osteogenic differentiation of human osteosarcoma cell (SaOS-2) and human bone marrow mesenchymal stem cells (hBMSCs). Furthermore, the Cu/CNTs-CaP-CS/Mg was prepared to improve the bioactivity and antibacterial activity of the composites. The results indicated that CNTs-CaP-CS/Mg composites were suitable for proliferation and differentiation of SaOS-2 cells. Stimulated by the CNTs-CaP-CS/Mg extracts, the ALP expression of hBMSCs increased in the first 16 days and the mineralization ability of hBMSCs was highly expressed throughout the whole process which might be through the Erk1/2 signaling pathway. After CNTs-loaded Cu element, the bioactivity of the coating was satisfactory. Moreover, this new implant exhibited excellent antibacterial properties for Escherichia coli (E. coli) and Staphylococcus albus (S. albus). Collectively, these data suggest that the CNTs-CaP-CS/Mg and Cu/CNTs-CaP-CS/Mg might be potentially applied as bone implants for future clinical use.

Mechanosensitive miR-99b mediates the regulatory effect of matrix stiffness on bone marrow mesenchymal stem cell fate both in vitro and in vivo.

Mechanical signals from extracellular matrix stiffness are important cues that regulate the proliferation and differentiation of bone marrow mesenchymal stem cells (BMSCs). However, the incorporation of BMSCs into soft hydrogels and the dominance of soft matrices for BMSC growth and differentiation limit the directed differentiation of BMSCs incorporated into hydrogels for tissue engineering, especially osteogenesis. Here, we found that the expression of miR-99b increased with increasing hydrogel stiffness and that miR-99b regulated the proliferation and differentiation of BMSCs seeded on the surface of substrates with different stiffnesses. Furthermore, miR-99b significantly promoted the migration of BMSCs in 3D hydrogels. Mechanistically, we demonstrated that matrix stiffness-sensitive miR-99b targets the mammalian target of the rapamycin signaling pathway to regulate the adipogenic and osteogenic differentiation of BMSCs. In addition, by modulating the expression of miR-99b, the osteogenic differentiation of BMSCs in soft 3D hydrogels was promoted. Consistently, the flexible BMSC-GelMA hydrogel transfected with miR-99b significantly promoted bone regeneration in the rat calvarial defect area. These results suggest that miR-99b plays a key role in the mechanotransduction and phenotypic transformation of BMSCs and may inspire new tissue engineering applications with MSCs as key components.

Bioactive mineralized small intestinal submucosa acellular matrix/PMMA bone cement for vertebral bone regeneration.

Polymethylmethacrylate (PMMA) bone cement extensively utilized for the treatment of osteoporotic vertebral compression fractures due to its exceptional handleability and mechanical properties. Nevertheless, the clinical application of PMMA bone cement is restricted by its poor bioactivity and excessively high modulus of elasticity. Herein, mineralized small intestinal submucosa (mSIS) was incorporated into PMMA to prepare a partially degradable bone cement (mSIS-PMMA) that provided suitable compressive strength and reduced elastic modulus compared to pure PMMA. The ability of mSIS-PMMA bone cement to promote the attachment, proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells was shown through cellular experiments carried out in vitro, and an animal osteoporosis model validated its potential to improve osseointegration. Considering these benefits, mSIS-PMMA bone cement shows promising potential as an injectable biomaterial for orthopedic procedures that require bone augmentation.

Low oxygen tension affects proliferation and senescence of caprine bone marrow mesenchymal stem cells in in vitro culture condition

The culture system of bone marrow mesenchymal stem cells (bmMSCs) in the normoxic environment does not imitate the hypoxic milieu of typical biological conditions, thus hypoxic culture conditions may improve survival, and growth attributes of bmMSCs during in vitro culture. Therefore, the present study was conducted at ICAR-CIRG, Makhdoom during year 2020 with the objective to investigate the changes in biological characteristics of cultured caprine bmMSCs (cbmMSCs) including the cellular senescence, survival, rate of proliferation, immuno-phenotypic characteristics, and gene expression pattern in a normal and hypoxic microenvironment condition. For this, cbmMSCs isolated from bone marrow collected from iliac crest were enriched and grown under either hypoxic (5% O2) or normoxic (20% O2) conditions. Thereafter, the outcome of hypoxic (5% O2) culturing of cbmMSCs on growth characteristics, proliferation, senescence, and expression profile of important stemness-associated (OCT-4) and oxidative stress [glutathione peroxidase (GPx1) and copper-zinc superoxide dismutase (CuZnSOD)] marker genes was evaluated. cbmMSCs cultivated in hypoxic conditions showed higher proliferation and decreased population doubling time and senescence-associated β-GAL expression; however, the immune-phenotypic characteristics of the cells remain unchanged. Furthermore, the culture of cbmMSCs in hypoxia increased the expression of OCT-4, GPx1, and CuZnSOD, compared with the cells grown under normoxia. In conclusion, the culture condition with low O2 level improved the growth characteristics and proliferation of cbmMSCs. These outcomes would provide information to formulate strategies for the collection and efficient in vitro expansion of bmMSCs from goats and other farm animals before their downstream applications.

The additive effects of bioactive glasses and photobiomodulation on enhancing bone regeneration.

Bioactive glasses (BG) have been generally used in bone defects repair for its good osteoinductivity and osteoconductivity. However, the early angiogenesis of BG in the repair of large-sized bone defects may not be sufficient enough to support new bone formation, resulting in the failure of bone repair. Photobiomodulation (PBM) therapy, which is superior on promoting early angiogenesis, may contribute to the angiogenesis of BG and further enhance the repair of bone defects. Therefore, we applied BG and PBM in combination and preliminarily investigated their additive effects on bone regeneration both in vitro and in vivo. The in vitro results revealed that BG combined with PBM remarkably enhanced human bone marrow mesenchymal stem cells proliferation, osteogenic-related genes expression and mineralization, which was better than applying BG or PBM respectively. For in vivo studies, the histological staining results showed that BG induced new bone formation in the interior of defects and promoted new bone reconstruction at 6 weeks post-operation. The micro-computed tomography results further confirmed that BG combined with PBM accelerated bone formation and maturation, improved the speed and quality of bone regeneration, and promoted bone repair. In conclusion, with the optimum BG and PBM parameters, BG combined with PBM generated additive effects on promoting bone regeneration.

Bismuth-coated 80S15C bioactive glass scaffolds for photothermal antitumor therapy and bone regeneration.

Background: Malignant bone tumors usually occur in young people and have a high mortality and disability rate. Surgical excision commonly results in residual bone tumor cells and large bone defects, and conventional radiotherapy and chemotherapy may cause significant side effects. In this study, a bifunctional Bi-BG scaffold for near-infrared (NIR)-activated photothermal ablation of bone tumors and enhanced bone defect regeneration is fabricated. Methods: In this study, we prepared the Bi-BG scaffold by in-situ generation of NIR-absorbing Bi coating on the surface of a 3D-printing bioactive glass (BG) scaffold. SEM was used to analyze the morphological changes of the scaffolds. In addition, the temperature variation was imaged and recorded under 808nm NIR laser irradiation in real time by an infrared thermal imaging system. Then, the proliferation of rat bone mesenchymal stem cells (rBMSCs) and Saos-2 on the scaffolds was examined by CCK-8 assay. ALP activity assay and RT-PCR were performed to test the osteogenic capacity. For in vivo experiments, the nude rat tumor-forming and rat calvarial defect models were established. At 8weeks after surgery, micro-CT, and histological staining were performed on harvested calvarial samples. Results: The Bi-BG scaffolds have outstanding photothermal performance under the irradiation of 808nm NIR at different power densities, while no photothermal effects are observed for pure BG scaffolds. The photothermal temperature of the Bi-BG scaffold can be effectively regulated in the range 26-100°C by controlling the NIR power density and irradiation duration. Bi-BG scaffolds not only significantly induces more than 95% of osteosarcoma cell death (Saos-2) in vitro, but also effectively inhibit the growth of bone tumors in vivo. Furthermore, they exhibit excellent capability in promoting osteogenic differentiation of rBMSCs and finally enhance new bone formation in the calvarial defects of rats. Conclusion: The Bi-BG scaffolds have bifunctional properties of photothermal antitumor therapy and bone regeneration, which offers an effective method to ablate malignant bone tumors based on photothermal effect.

Comparing the mesenchymal stem cells proliferation rate with different labeling assessments

Comparing the mesenchymal stem cells proliferation rate with different labeling assessments

Effect of super activated platelet lysate on cell proliferation, repair and osteogenesis.

Platelet lysate (PL) is considered as an alternative to fetal bovine serum (FBS) and facilitates the proliferation and differentiation of mesenchymal cells. The aim of this study is to explore whether super activated platelet lysate (sPL), a novel autologous platelet lysate, has the ability to inhibit inflammation and promote cell proliferation, repair and osteogenesis as a culture medium. Different concentrations of sPL on human fetal osteoblastic 1.19 cell line (hFOB1.19) proliferation and apoptotic repair were investigated; And detected proliferative capacity, inflammatory factor expressions and osteogenic differentiation of human dental pulp cells (hDPCs) stimulated by LPS under 10% FBS and 5% sPL mediums. sPL promoted hFOB1.19 proliferation and had repairing effects on apoptotic cells. No significant difference in proliferation and IL-1α, IL-6 and TNF-α expressions of hDPCs in FBS and sPL medium stimulated by LPS. hDPCs in sPL osteogenic medium had higher osteogenic-related factor expressions and ALP activity. LPS promoted osteogenic-related factor expressions and ALP activity of hDPCs in FBS osteogenic medium, but opposite effect showed in sPL medium. sPL promoted osteoblast proliferation and had restorative effects. Under LPS stimulation, sPL did not promote hDPCs proliferation or inhibit inflammation. sPL promotes osteogenic differentiation of hDPCs.

Cobalt Chloride Promotes Osteogenesis of Rat Bone Marrow Mesenchymal Stem Cells In Vitro and In Vivo

This work aimed to investigate the effect of low-concentration cobalt chloride on the in vitro and in vivo proliferation of rat bone mesenchymal stem cells, the expression of hypoxia-inducing fraction-1 alpha and the related osteogenic genes. The bone mesenchymal stem cells were isolated from bone marrow of rats, and the surface biomarkers were identified by immunofluorescence staining and flow cytometry. The differentiation of bone mesenchymal stem cells was measured by alizarin red and alkaline phosphatase staining. The bone mesenchymal stem cells were treated with cobalt chloride at different concentrations and cell viability was assessed by cell counting kit 8. Cell migration was detected by Transwell and wound healing assay. The expression of collagen type 1, bone morphogenetic protein-2, runt-related transcription factor 2, alkaline phosphatase and hypoxia-inducing fraction-1 alpha were measured by quantitative real time polymerase chain reaction assay. The large segmental defect model was made to mimic the in vivo bone defect. The bone mesenchymal stem cells-collagen sponge scaffold was adopted for in vivo treatment and histological analysis of femur structure was performed to assess the effects of cobalt chloride-treated bone mesenchymal stem cells in promoting bone formation. X-ray and micro computed tomography were performed to observe bone structure. The cluster of differentiation 90 and cluster of differentiation 44 were highly expressed and cluster of differentiation 45 expression was relatively low in isolated bone mesenchymal stem cells. The cobalt chloride at 300 and 400 μmol/l could effectively suppress cell proliferation, compared with the control group. The low dose of cobalt chloride (50 μmol/l and 100 μmol/l) could promote cell proliferation. The cobalt chloride at 100 μmol/l could increase the positive staining of alkaline phosphatase and alizarin red. The expression of collagen type 1, bone morphogenetic protein-2, runt-related transcription factor 2, alkaline phosphatase and hypoxiainducing fraction-1 alpha were statistically up-regulated by cobalt chloride treatment. The cobalt chloridebone mesenchymal stem cells-collagen scaffold effectively accelerated the bone regeneration, increased new bone deposition and bone morphogenetic protein-2 expression in femur tissues. Appropriate concentration of cobalt chloride can promote the proliferation of bone mesenchymal stem cells and up-regulate the expression of hypoxia-inducing fraction-1 alpha and osteogenic genes in vitro, simultaneously promoted bone regeneration in vivo.

Aesthetic Approach for a Buccal Solitary Fibrous Tumor

Solitary fibrous tumors (SFTs) are caused by the proliferation of mesenchymal cells. Facial SFTs are rare. Resection scar (of a subcutaneous tumor in the buccal area) is distinctive if it is located at the center of the cheek. To avoid this complication, we resected the lesion using a preauricular incision to approach the superficial musculoaponeurotic system, an approach similar to that used during rhytidectomy (face-lift). A 42-year-old woman underwent tumor resection using this approach. Eight months after, no tumor recurrence was observed. Additionally, no scarring or facial nerve paralysis was observed. Immunostaining of the tumor cells revealed CD34-positive, Bcl-2-positive, STAT6-positive, and some SMA-positive cells, and SFT was diagnosed. This case falls into the low-risk SFT group. Therefore, careful follow-up is necessary for SFTs because they have a high risk of recurrence and local metastasis.