Uranium inhibits bone formation in physiologic alveolar bone modeling and remodeling

The aim of this study was to investigate the behavior of dental-derived human mesenchymal stem cells (d-hMSCs) in response to differently surface-treated implants and to evaluate the effect of d-hMSCs on local osteogenesis around an implant in vivo. d-hMSCs derived from alveolar bone were established and cultured on machined, sandblasted and acid-etched (SLA)-treated titanium discs with and without osteogenic induction medium. Their morphological and osteogenic potential was assessed by scanning electron microscopy (SEM) and real-time polymerase chain reaction (RT-PCR) via mixing of 5 × 106 of d-hMSCs with 1 mL of Metrigel and 20 μL of gel-cell mixture, which was dispensed into the defect followed by the placement of customized mini-implants (machined, SLA-treated implants) in New Zealand white rabbits. Following healing periods of 2 weeks and 12 weeks, the obtained samples in each group were analyzed radiographically, histomorphometrically and immunohistochemically. The quantitative change in osteogenic differentiation of d-hMSCs was identified according to the type of surface treatment. Radiographic analysis revealed that an increase in new bone formation was statistically significant in the d-hMSCs group. Histomorphometric analysis was in accordance with radiographic analysis, showing the significantly increased new bone formation in the d-hMSCs group regardless of time of sacrifice. Human nuclei A was identified near the area where d-hMSCs were implanted but the level of expression was found to be decreased as time passed. Within the limitations of the present study, in this animal model, the transplantation of d-hMSCs enhanced the new bone formation around an implant and the survival and function of the stem cells was experimentally proven up to 12 weeks post-sacrifice.

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Cyclodextrin-Based Supramolecular Complexes of Osteoinductive Agents for Dental Tissue Regeneration

Pharmaceutics ◽

10.3390/pharmaceutics13020136 ◽

2021 ◽

Vol 13 (2) ◽

pp. 136

Author(s):

Masahiko Terauchi ◽

Atsushi Tamura ◽

Yoshinori Arisaka ◽

Hiroki Masuda ◽

Tetsuya Yoda ◽

...

Keyword(s):

Growth Factors ◽

Bone Formation ◽

Small Molecule ◽

Tissue Regeneration ◽

Alveolar Bone ◽

Inclusion Complexation ◽

Dental Tissue ◽

Polyelectrolyte Complexes ◽

Small Molecule Drugs

Oral tissue regeneration has received growing attention for improving the quality of life of patients. Regeneration of oral tissues such as alveolar bone and widely defected bone has been extensively investigated, including regenerative treatment of oral tissues using therapeutic cells and growth factors. Additionally, small-molecule drugs that promote bone formation have been identified and tested as new regenerative treatment. However, treatments need to progress to realize successful regeneration of oral functions. In this review, we describe recent progress in development of regenerative treatment of oral tissues. In particular, we focus on cyclodextrin (CD)-based pharmaceutics and polyelectrolyte complexation of growth factors to enhance their solubility, stability, and bioactivity. CDs can encapsulate hydrophobic small-molecule drugs into their cavities, resulting in inclusion complexes. The inclusion complexation of osteoinductive small-molecule drugs improves solubility of the drugs in aqueous solutions and increases in vitro osteogenic differentiation efficiency. Additionally, various anionic polymers such as heparin and its mimetic polymers have been developed to improve stability and bioactivity of growth factors. These polymers protect growth factors from deactivation and degradation by complex formation through electrostatic interaction, leading to potentiation of bone formation ability. These approaches using an inclusion complex and polyelectrolyte complexes have great potential in the regeneration of oral tissues.

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Myosins in Osteoclast Formation and Function

Biomolecules ◽

10.3390/biom8040157 ◽

2018 ◽

Vol 8 (4) ◽

pp. 157 ◽

Cited By ~ 8

Author(s):

Beth Lee

Keyword(s):

Actin Cytoskeleton ◽

Motor Proteins ◽

Current Knowledge ◽

Osteoclast Differentiation ◽

Osteoclast Formation ◽

Bone Modeling ◽

Cell Type ◽

And Function ◽

Bone Modeling And Remodeling

Skeletal quantity and quality are determined by processes of bone modeling and remodeling, which are undertaken by cells that build and resorb bone as they respond to mechanical, hormonal, and other external and internal signals. As the sole bone resorptive cell type, osteoclasts possess a remarkably dynamic actin cytoskeleton that drives their function in this enterprise. Actin rearrangements guide osteoclasts’ capacity for precursor fusion during differentiation, for migration across bone surfaces and sensing of their composition, and for generation of unique actin superstructures required for the resorptive process. In this regard, it is not surprising that myosins, the superfamily of actin-based motor proteins, play key roles in osteoclast physiology. This review briefly summarizes current knowledge of the osteoclast actin cytoskeleton and describes myosins’ roles in osteoclast differentiation, migration, and actin superstructure patterning.

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Experimental Studies on Alveolar Bone Formation with .ALPHA.-TCP-Collagen Material.

Nihon Hotetsu Shika Gakkai Zasshi ◽

10.2186/jjps.44.19 ◽

2000 ◽

Vol 44 (1) ◽

pp. 19-24

Author(s):

Masanori Muraoka

Keyword(s):

Bone Formation ◽

Alveolar Bone ◽

Experimental Studies

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Effects of sialoadenectomy and exogenous EGF on molar drift and orthodontic tooth movement in rats

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1994.266.5.e731 ◽

1994 ◽

Vol 266 (5) ◽

pp. E731-E738 ◽

Cited By ~ 2

Author(s):

C. Dolce ◽

J. Anguita ◽

L. Brinkley ◽

P. Karnam ◽

M. Humphreys-Beher ◽

...

Keyword(s):

Bone Formation ◽

Bone Remodeling ◽

Alveolar Bone ◽

Tooth Movement ◽

Orthodontic Tooth Movement ◽

Alveolar Bone Remodeling ◽

Tooth Roots ◽

Epidermal Growth ◽

Tetracycline Labeling ◽

Distal Aspect

Effects on bone remodeling have been attributed to epidermal growth factor (EGF). Sialoadenectomy (SX) removes the major source of EGF in rodents and decreases both salivary and serum EGF levels. EGF effects on rat alveolar bone remodeling manifested by molar drift (MD) and orthodontic tooth movement (OTM) were examined using the following two approaches: 1) EGF depletion by SX and replacement by orally administered EGF (50 micrograms.animal-1.day-1); 2) sham rats supplemented with matching amounts of EGF. MD and OTM were measured using cephalometric radiographs; bone formation was measured histomorphometrically using tetracycline labeling. Normal MD was not detected after SX, and alveolar bone formation was significantly reduced both around the tooth and in nondental sites. Replacement EGF given to SX rats and supplemental EGF administered to sham rats changed the direction and enhanced the rate of MD. A mesially directed orthodontic force applied to the molars of SX animals increased bone formation on the distal aspect of the tooth roots. Supplemental EGF did not significantly affect OTM. EGF affects alveolar bone remodeling, as manifested clinically by alterations in normal maxillary MD.

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ANABOLIChESKAYa TERAPIYa OSTEOPOROZA.TERIPAPARATID: EFFEKTIVNOST', BEZOPASNOST' I OBLAST' PRIMENENIYa

Osteoporosis and Bone Diseases ◽

10.14341/osteo2013232-40 ◽

2013 ◽

Vol 16 (2) ◽

pp. 32-40

Author(s):

Zh E BELAYa ◽

L Ya ROZhINSKAYa

Keyword(s):

Bone Formation ◽

Bone Remodeling ◽

Vertebral Fractures ◽

Previous Treatment ◽

Fragility Fractures ◽

Bone Modeling ◽

Severe Osteoporosis ◽

Subcutaneous Injections ◽

Acid Fragment ◽

History Of

This review of the literature has been dedicated to experimental and clinical studies of mechanism of action and efficacy of 1—34 amino acid fragment of parathyroid hormone — teriparatide as well as others contries experience of its prescribtion. Teriparatide is an osteoanabolic agent which stimulates bone formation by affecting bone modeling and by stimulating bone remodeling. The effects on modeling lead to increased bone formation whereas the effects on bone remodeling lead to increased bone turnover. Thus, in its mode of action teriparatide differs from all others medicines currently available to treat osteoporosis. Daily subcutaneous injections of teriparatide are proved to be effective to prevent low-traumatic vertebral and non-vertebral fractures in postmenopausal women with the history of vertebral fractures. Teriparatide is effective to treat osteoporosis in male and even more effective than alendronate to treat glucocorticoid-induced osteoporosis. Due to high cost and some restriction related to the duration of therapy (up to 18 months in Russia and 24 months in others countries) teriparatide should be recommended to treat severe osteoporosis in patients with a history >1 moderate clinical vertebral fracture or two or more vertebral fragility fractures or in case the previous treatment was not effective. Teriparatide should be prescribed after bisphosphonates or other antiosteoporotic treatment, but not in the combination with bisphosphonates. The prescribtion of bisphosphonates after teriparatide is effective to maintaine and further improve the effect. Thus, teriparatide is effective to treat severe osteoporosis and osteoporosis resistant to other therapy.

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