CKIP-1 regulates the immunomodulatory function of mesenchymal stem cells.

Mesenchymal stem cells (MSCs) are self-renewing multipotent cells with immunoregulatory function, which makes them attractive candidates for regenerative medicine. However, the detailed mechanisms of their immunomodulatory capacity are not fully characterized. Here, we found that casein kinase 2 interacting protein-1 (CKIP-1) expression was induced in the murine MSC cell line C3H/10T1/2 by LPS. Knockdown of CKIP-1 did not cause significant differences on the cell cycle or immunophenotype of MSCs. However, MSCs with CKIP-1 knockdown showed enhanced immunosuppressive capacity. Real-time PCR and western blot analyses revealed that compared with the control group, MSCs with CKIP-1-knockdown exhibited higher IL-10 production and p38 MAPK phosphorylation following LPS treatment. Interestingly, the expression of CKIP-1 was decreased in MSCs following high glucose treatment. Furthermore, MSCs became more immunosuppressive after high glucose treatment, as shown by higher IL-10 production and enhanced inhibition of T cell proliferation. Collectively, our data reveal a novel role for CKIP-1 in regulating MSC-mediated immunomodulation, and indicate that MSCs become more immunosuppressive under high glucose conditions. These new insights may help in the development of future applications of MSCs.

Sudden sensorineural hearing loss (SSHL) following a local anesthetic dental procedure.

Acute sensorineural hearing loss is an uncommon phenomenon in dentistry. We describe the case of a 79-year-old male who presented with acute sensorineural hearing loss occurring 2 days after a tooth extraction procedure under local anesthesia. Possible mechanisms are discussed. He was treated with vasodilators (Ginaton and Alprostadil Injection) and Mecobalamin injection with benefit. High dose oral steroids (1 mg/kg) and low molecular weight dextran were used.

HDAC6 regulates dental mesenchymal stem cells and osteoclast differentiation.

BACKGROUND: Dental and periodontal tissue development is a complicated process involving a finely regulated network of communication among various cell types. Understanding the mechanisms involved in regulating dental mesenchymal stem cells (MSCs) and osteoclast cell differentiation is critical. However, it is still unclear whether histone deacetylase HDAC6 is involved in dental MSCs fate determination and osteoclast differentiation. METHODS: We used shRNA and siRNA knockdown to explore the role of HDAC6 in dental MSCs odontogenic differentiation and osteoclasts maturation. RESULTS: Based on HDAC6 knockdown dental MSCs, our data suggest that HDAC6 knockdown significantly increases alkaline phosphate activity and mineralized nodules formation. Additionally, mRNA expression of odontogenic marker genes (OSX, OCN, and OPN) was induced by HDAC6 knockdown. By using HDAC6 siRNA, we knocked down HDAC6 in osteoclast precursor RAW 264.7 cells. Our data suggests that HDAC6 knockdown significantly inhibited osteoclasts differentiation. Additionally, mRNA expression of osteoclast marker genes Trap, Mmp9, and Ctsk was decreased by HDAC6 knockdown. CONCLUSIONS: Our study demonstrated that HDAC6 plays an important role in regulating dental MSCs and osteoclasts differentiation.

[MicroRNA-20a Promotes Osteogenic Differentiation of C3H/10T1/2 Cells through Regulating CKIP-1 Expression].

OBJECTIVE: To investigate the effect of microRNA-20a(MiR-20a) on osteogenic differentiation of mouse C3H/10T1/2 cells and its regulatory mechanism. METHODS: Osteogenic differentiation of C3H/10T1/2 cells were identified by ALP staining and qRT-PCR. MiR-20a mimics and CKIP-1 siRNA were transfected into C3H/10T1/2 cells respectively with lipo3000. The expression of osteoblast marker genes, miR-20a and CKIP-1 were quantitatively assessed by qRT-PCR. RESULTS: miR-20a expression was up-regulated during osteoblast differentiation of C3H/10T1/2 cells. Overexpression of miR-20a promoted osteogenic differentiation. Furthermore, miR-20a inhibited the expression of bone formation negative regulator CKIP-1. Additionally, CKIP-1 knockdown promoted osteogenic differentiation. CONCLUSION: MiR-20a promotes osteogenic differentiation of C3H/10T1/2 cells possibly through inhibiting the expression of CKIP-1.

Aging performances for resisting low-temperature of three dental Yttria-stabilized zirconia ceramic core materials.

BACKGROUND: The low-temperature resistance aging performance of Yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) is the key effective factor that influences the long-term success rate of prosthesis. The objective of this study was to test and compare the aging performances for resisting low temperature of Lava Frame, Cercon Smart, and Upcera Yttria-stabilized zirconia core materials, via analyzing the micro and the crystal phases of the materials, and measure the three-point bending strength and the fracture toughness. METHODS: The three zirconia green bodies were prepared as 60 test samples for three-point bending strength and as 60 test samples for fracture toughness. The test samples for three-point bending strength and fracture toughness were assigned to five groups and were treated respectively for 0, 5, 10, 15, and 20 hours to observe the micro and the crystal phases of the test samples. Then the three-point bending strength and fracture toughness were tested by X-ray diffraction (XRD). RESULTS: The m phase content of Lava Frame was raised from 7.70% to 13.01%; the m phase content of Cercon Smart was raised from 4.95% to 8.53%; and Lava Frame is raised from 10.84% to 35.18%. The three-point bending strengths of the three zirconia core materials were higher than 1100 MPa and the fracture toughness was higher than 3 MPa·m(1/2). The three-point bending strength and the fracture toughness of Upcra zirconia decreased the most, followed by Lava Frame, and then by Cercon Smart. CONCLUSION: The aging resistance sequences of the three zirconia core materials are, from strong to weak, Cercon Smart, Lava Frame, and Upcera.

Posterolateral spinal fusion with nano-hydroxyapatite-collagen/PLA composite and autologous adipose-derived mesenchymal stem cells in a rabbit model.

Spinal fusion is routinely performed to treat low back pain caused by degeneration of intervertebral discs. An autologous bone graft derived from the iliac crest is the standard procedure used for spinal fusion. However, several shortcomings, including pseudarthrosis, pain and the need for blood transfusion are known to be associated with the procedure. Our study analysed the effectiveness of a new mineralized collagen matrix, nano-hydroxyapatite-collagen-polylactic acid (nHAC-PLA), combined with autologous adipose-derived mesenchymal stem cells (ADMSCs) as a graft material for posterolateral spinal fusion in a rabbit model. Forty rabbits were randomly divided into four groups: autologous iliac crest bone group (ACB), nHAC-PLA composite group (nHAC-PLA), autologous iliac crest bone mixed with nHAC-PLA composite group (ACB + nHAC-PLA), and nHAC-PLA composite combined with ADMSCs (ADMSCs + nHAC-PLA). The viability and the proliferation of the ADMSCs seeded on the scaffolds were evaluated by live/dead kit and MTT assay in vitro, respectively. Lumbar posterolateral fusions were assessed by manual palpation, radiographical and histological procedures, mechanical strength and scanning electronic microscopy (SEM) in 10 weeks of observation. The results showed that the rate of fusion was significantly higher in the ACB and ADMSCs + nHAC-PLA groups than that in the nHAC-PLA and ACB + nHAC-PLA groups. It was not significantly higher in the ACB group than in the ADMSCs + nHAC-PLA group. From microstructural analysis of the samples using histological staining methods, there was more new bone-like tissue formation in the ACB and ADMSCs + nHAC-PLA groups than that in the other two groups at the 10th postoperative week. Our study demonstrated the effective impact of nHAC-PLA combined with ADMSCs in rabbit posterolateral spinal fusion.

[Experiment on inducing human periodontal ligament stem cells into adipose cells].

OBJECTIVE: To explore the capability of human periodontal ligament stem cells (PDLSCs) differentiating into adipose cells in vitro and to determine their changes in cell morphology, structure and function during differentiation. METHODS: PDLSCs isolated by magnetic-activated cell selection were treated continuously with adipogenic medium for 21 d. Then the cell morphology, ultrastructure, adipose specific markers of low density lipoprotein (LPL) and peroxisome proliferator activated receptor-gamma (PPAR-gamma) were analyzed by inverted contrast microscope, trans mission electron microscope (TEM), flow cytometry, immunofluorescence, RT-PCR and Western blot, respectively. These adipose-like cells were also identified by oil red O staining to determine the formation of lipid droplet, and the non-induced cells were used as control. RESULTS: After continuous induction, the treated cells differentiated into adipose-like cells with round shape, and large amount of lipid drop in cytoplasm. 96.54% of the PDLSCs were found to differentiate into adipose cells as showed by flow cytometry, the specific markers of LPL mRNA and PPAR-gamma mRNA, and oil red O staining, respectively. Further, PPAR-gamma protein was detected in the induced cells in a time-dependent manner. CONCLUSION: Human PDLSCs have the potential of differentiating into adipose cells under appropriate condition, and the differentiated cells exhibited characteristics of adipose cells both from cell morphology and from their functions.

[Effect of right chewing-side preference on morphological temporomandibular joint changes].

PURPOSE: To explore the effect of right chewing-side preference on temporomandibular joint with cone-beam computed tomography (CBCT). METHODS: Fifty-two patients who were diagnosed as right chewing-side preference were selected and scanned by CBCT in the intercuspal position. The interested region was chosen to reconstruct and the images of bony structure of TMJ at axial view, coronal position, sagittal position, oblique position parallelled to the long axis of condyle and oblique position vertical to the long axis of condyle were evaluated. The data was analyzed with SPSS12.0 software package for paired t test. RESULTS: There was significant difference between the habitual and unhabitual sides of the joint space of 60° and 90° at oblique position parallelled to the long axis of condyle (P