Effect of rhBMP-7 combined with two bone grafts on human periodontal ligament cell differentiation

Assessment of bone morphogenetic protein-7 loaded chitosan/β-Glycerophosphate hydrogel on periodontium tissues regeneration of class III furcation defects

Background

Periodontitis is a long-term, multifactorial inflammatory condition that is triggered by bacterial germs and interacts with the host's immune system. The unique attachment of fibrous tissue between the cementum and bone presents a challenge for periodontal regeneration.

Aim

To achieve the lowest optimum dose of BMP-7 that helps in periodontal regeneration, involving newly formed cementum, PDL and bone.

Materials and methods

Five healthy mongrel dogs were used for the study. A critical class III furcation defect was created using rotating burs. The bone defects (ten defects for each group) were allocated to one of the subsequent groups: (Group 1) control with the surgical defect only. (Group 2) Surgical defect implanted with hydrogel only (CS/β-GP). (Group 3) Surgical defect implanted with CS/BMP-7 (50 ng/ml). (Group 4) Surgical defect implanted with CS/BMP-7 (100 ng/ml).

Results

Histomorphometric and H&E analysis revealed a statistically significant difference in bone, PDL, and cementum regeneration defects filled with CS/BMP-7 (100 ng/ml) compared with other groups.

Conclusion

The standard effective dose for BMP-7 use in periodontal regeneration is 100 ng/ml.

Muscone Promotes The Adipogenic Differentiation Of Human Gingival Mesenchymal Stem Cells By Inhibiting The Wnt/β-Catenin Signaling Pathway

Objectives

This study was performed to evaluate the effects of muscone on the proliferation, migration and differentiation of human gingival mesenchymal stem cells (GMSCs) and to explore the relevant mechanisms.

Materials and methods

We performed studies to determine the effects and mechanisms of muscone on GMSC proliferation, migration and differentiation. We conducted CCK-8, colony formation, transwell chamber, scratch wound, alkaline phosphatase (ALP) staining and activity, and alizarin red and oil red O staining assays, as well as real-time quantitative polymerase chain reaction (qRT-PCR), to ascertain the effects of muscone on GMSC proliferation, migration and differentiation in vitro. The mechanism by which muscone influences the osteogenic and adipogenic differentiation of GMSCs was elucidated by qRT-PCR and Western blotting.

Results

We found that muscone significantly promoted GMSC proliferation, chemotaxis, wound healing and fat droplet formation and inhibited ALP activity and mineral deposition. Notably, we observed that the Wnt/β-catenin pathway was closely related to the ability of muscone to inhibit the osteogenic differentiation and promote the adipogenic differentiation of GMSCs. The effect of muscone on the multidirectional differentiation capacity of GMSCs was significantly reversed by the agonist lithium chloride through the Wnt/β-catenin signaling pathway.

Conclusion

Muscone effectively increased the proliferation and migration, promoted the adipogenic differentiation and inhibited the osteogenic differentiation of GMSCs by inhibiting the Wnt/β-catenin signaling pathway. These results may provide a theoretical basis for the application of GMSCs and muscone in tissue engineering and regenerative medicine.

Evaluation of the osteogenic potential of growth factor-rich demineralized bone matrix in vivo

BACKGROUND

The study evaluates the osteogenic properties and biocompatibility of growth factor-rich demineralized bone matrix (GDBM) by comparing with cancellous mineralized bone matrix (CMBM) and anorganic bovine bone matrix (ABBM).

METHODS

Thirty-six Sprague-Dawley rats were used (n = 6/group/time point). To assess biocompatibility and osteoinductivity, the respective bone matrices were randomly placed in subcutaneous pouches for 7 and 28 days and evaluated by histology and osteopontin expression. Osteoconductivity was assessed by randomly implanting respective bone matrices in osteotomies on femurs for 14 and 28 days and evaluated by microcomputed tomography and histology.

RESULTS

Neither acute inflammation nor mineralized tissue was noted in any of the subcutaneous specimens, whereas expression of osteopontin was more prominent in the GDBM group. Among the femoral specimens, the greatest relative bone volume (bone volume [BV] divided by trabecular volume [TV]) and trabecular thickness was noted in the ABBM group at both time points, whereas less BV/TV was noted in GDBM group at day 14. Residual matrix particles were noted in all examined groups at both time points, without significant differences regarding defect fill between groups. The GDBM group presented similar levels of newly formed bone compartment and marrow space to those of the ABBM group.

CONCLUSIONS

GDBM demonstrated acceptable biocompatibility and osteogenic potential comparable to ABBM in vivo. Further investigations in a more clinically relevant model are warranted.