Delivery of Alkaline Phosphatase Promotes Periodontal Regeneration in Mice

2021 ◽  
pp. 002203452110056
Author(s):  
A. Nagasaki ◽  
K. Nagasaki ◽  
B.D. Kear ◽  
W.D. Tadesse ◽  
V. Thumbigere-Math ◽  
...  
Keyword(s):  
Gene Expression ◽  
Computed Tomography ◽  
Alkaline Phosphatase ◽  
Alveolar Bone ◽  
Marker Gene ◽  
Periodontal Regeneration ◽  
Local Delivery ◽  
Micro Computed Tomography ◽  
Marker Gene Expression

Factors regulating the ratio of pyrophosphate (PPi) to phosphate (Pi) modulate biomineralization. Tissue-nonspecific alkaline phosphatase (TNAP) is a key promineralization enzyme that hydrolyzes the potent mineralization inhibitor PPi. The goal of this study was to determine whether TNAP could promote periodontal regeneration in bone sialoprotein knockout mice ( Ibsp−/− mice), which are known to have a periodontal disease phenotype. Delivery of TNAP was accomplished either systemically (through a lentiviral construct expressing a mineral-targeted TNAP-D10 protein) or locally (through addition of recombinant human TNAP to a fenestration defect model). Systemic TNAP-D10 delivered by intramuscular injection at 5 d postnatal (dpn) increased circulating alkaline phosphatase (ALP) levels in Ibsp−/− mice by 5-fold at 30 dpn, with levels returning to normal by 60 dpn when tissues were evaluated by micro–computed tomography and histology. Local delivery of recombinant human TNAP to fenestration defects in 5-wk-old wild type (WT) and Ibsp−/− mice did not alter long-term circulating ALP levels, and tissues were evaluated by micro–computed tomography and histology at postoperative day 45. Systemic and local delivery of TNAP significantly increased alveolar bone volume (20% and 37%, respectively) and cementum thickness (3- and 42-fold) in Ibsp−/− mice, with evidence for periodontal ligament attachment and bone/cementum marker localization. Local delivery significantly increased regenerated cementum and bone in WT mice. Addition of 100-μg/mL bovine intestinal ALP to culture media to increase ALP in vitro increased media Pi concentration, mineralization, and Spp1 and Dmp1 marker gene expression in WT and Ibsp−/− OCCM.30 cementoblasts. Use of phosphonoformic acid, a nonspecific inhibitor of sodium Pi cotransport, indicated that effects of bovine intestinal ALP on mineralization and marker gene expression were in part through Pi transport. These findings show for the first time through multiple in vivo and in vitro approaches that pharmacologic modulation of Pi/PPi metabolism can overcome periodontal breakdown and accomplish regeneration.

scholarly journals miR-539 mediates osteoblast mineralization by regulating Distal-less genes 2 in MC3T3-E1 cell line

2017 ◽  
Vol 12 (1) ◽  
pp. 294-299 ◽  
Author(s):  
Jianguo Han ◽  
Li Su ◽  
Chunyang Zhang ◽  
Rongcai Jiang
Keyword(s):  
Gene Expression ◽  
Alkaline Phosphatase ◽  
Cell Line ◽  
Osteoblast Differentiation ◽  
Marker Gene ◽  
Inhibitory Effect ◽  
Negative Regulator ◽  
Expression Level ◽  
Matrix Mineralization ◽  
Marker Gene Expression

AbstractmicroRNAs (miRNAs) play an important role in osteoblast differentiation. However, the mechanisms of miRNAs regulating osteoblast mineralization still needs to be further cleared. Distal-less genes 2 (Dlx2) plays an important role in osteoblast differentiation. We have found that miR-539 was significantly downregulated and Dlx2 was found to be inversely correlated with miR-539 in MC3T3-E1 cell line during osteoblast mineralization. The overexpression of miR-539 significantly decreased the expression level of Dlx2 and suppressed the osteogenic marker gene expression level, alkaline phosphatase activity and matrix mineralization. Our study showed that miR-539 was a negative regulator in osteoblast mineralization and that the targeting of Dlx2 gene partly contributes to this inhibitory effect exerted by miR-539.

scholarly journals Application of Biodegradable PLGA-PEG-PLGA/CPC Composite Bone Cement in the Treatment of Osteoporosis

Coatings ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 827
Author(s):  
Chao Guo ◽  
Dongyang Niu ◽  
Jia Liu ◽  
Xiaogang Bao ◽  
Guohua Xu
Keyword(s):  
Computed Tomography ◽  
Alkaline Phosphatase ◽  
Bone Cement ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Micro Computed Tomography ◽  
Alizarin Red ◽  
Treatment Of Osteoporosis ◽  
Composite Bone

The aim of this study was to evaluate the biological activity, safety, and effectiveness of poly(lactic acid)–poly(glycolic acid)–poly(ethylene glycol)–calcium phosphate cement (PLGA-PEG-PLGA/CPC). Methods: The PLGA-PEG-PLGA/CPC composite bone cement was used for interaction with MC3T3-E1 mouse osteoblasts in vitro and its compatibility was tested using Cell Counting Kit-8 (CCK-8). Alizarin Red staining and alkaline phosphatase activity were used to detect the osteogenic properties. Twenty healthy female New Zealand rabbits were selected to establish osteoporosis models, which were randomly divided into two groups. The experimental group was treated with 30 wt.% PLGA-PEG-PLGA/CPC, while the control group was treated with polymethyl methacrylate (PMMA) bone cement. Imaging and histomorphology of the vertebral body were analyzed after 12 weeks. The distribution and degradation of bone cement were assessed using micro-computed tomography examination and hematoxylin–eosin (HE) staining. Results: In vitro, CCK-8 revealed significant proliferation of osteoblasts in the PLGA-PEG-PLGA/CPC composite bone cement. Alizarin Red staining showed that the degree of staining increased with time. Quantitative results showed that absorbance was significantly higher in this group than in the CPC group on days 7 and 14. The alkaline phosphatase activity levels on days 7 and 14 were significantly higher in the 30 wt.% PLGA-PEG-PLGA/CPC group than in the CPC group. In vivo, postoperative micro-computed tomography and histomorphology showed that the material was evenly distributed in the vertebral body and a small amount penetrated into the trabecular bone. After 12 weeks, CPC degradation and absorption and the formation of new bone matrix were observed and the formation of a callus was obvious. Conclusion: PLGA-PEG-PLGA/CPC composite bone cement has a positive effect on the treatment of osteoporosis.

scholarly journals Sp1-dependent activation of KLF4 is required for PDGF-BB-induced phenotypic modulation of smooth muscle

2009 ◽  
Vol 296 (4) ◽  
pp. H1027-H1037 ◽  
Author(s):  
Rebecca A. Deaton ◽  
Qiong Gan ◽  
Gary K. Owens
Keyword(s):  
Gene Expression ◽  
Transcription Factor ◽  
Smooth Muscle ◽  
Vascular Injury ◽  
Marker Gene ◽  
Negative Regulator ◽  
Phenotypic Modulation ◽  
Marker Gene Expression

There is clear evidence that the phenotypic modulation of smooth muscle cells (SMCs) contributes to the pathophysiology of vascular disease. Phenotypic modulation refers to the unique ability of SMCs to alter their phenotype in response to extracellular stimuli and is hallmarked by the loss of SMC marker gene expression. The transcription factor Krüppel-like factor 4 (KLF4) is a known powerful negative regulator of SMC marker gene expression that works, in part, by decreasing the expression of the serum response factor (SRF) myocardin. KLF4 is not expressed in healthy adult SMCs but is increased in SMCs in response to vascular injury in vivo or PDGF-BB treatment in vitro. The aim of the present study was to determine the molecular mechanisms that regulate the expression of KLF4 in phenotypically modulated SMCs. The results demonstrated that the transcription factor stimulating protein-1 (Sp1) regulated the expression of KLF4 in SMCs. The KLF4 promoter contains three consensus Sp1 binding sites. Using a series of truncated KLF4 promoters, we showed that only fragments containing these Sp1 sites could be activated by PDGF-BB. In addition, overexpression of Sp1 alone was sufficient to increase the activity of the KLF4 promoter. Moreover, inhibiting Sp1 expression with small-interfering RNA attenuated the effects of PDGF-BB on KLF4 expression. Mutation of the three Sp1 sites within the KLF4 promoter abolished both baseline and PDGF-BB-induced activity. Finally, the results demonstrated enhanced Sp1 binding to the KLF4 promoter in SMCs treated with PDGF-BB in vitro and following vascular injury in vivo. Taken together, the results suggest a novel role for Sp1 in increasing the expression of KLF4 in phenotypically modulated SMCs.

scholarly journals Microstructural Observation with MicroCT and Histological Analysis of Human Alveolar Bone Biopsy from a Planned Implant Site: A Case Report

2013 ◽  
Vol 7 (1) ◽  
pp. 47-54 ◽  
Author(s):  
Emi Yamashita-Mikami ◽  
Mikako Tanaka ◽  
Naoki Sakurai ◽  
Kazuho Yamada ◽  
Hayato Ohshima ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Bone Tissue ◽  
Alveolar Bone ◽  
Bone Biopsy ◽  
Three Dimensional ◽  
Bone Sample ◽  
Biopsy Sample ◽  
Micro Computed Tomography ◽  
Metabolic Markers ◽  
Normal Ranges

The subject was a 53-year-old male. An alveolar bone sample was obtained from the site of the lower left first molar, before dental implant placement. Although the details of the trabecular structure were not visible with conventional computed tomography, micro-computed tomography (microCT) three-dimensional images of the alveolar bone biopsy sample showed several plate-like trabeculae extending from the lingual cortical bone. Histological observations of the bone sample revealed trabeculae, cuboidal osteoblasts, osteoclasts and hematopoietic cells existing in the bone tissue at the implantation site. Bone metabolic markers and calcaneal bone density were all within normal ranges, indicating no acceleration of the patient’s bone metabolism.Using microCT, and histological and histomorphometrical techniques, a great deal of valuable information about the bone tissue was obtained from a biopsy sample extracted from the patient’s planned implant site.

scholarly journals A Graded Multifunctional Hybrid Scaffold with Superparamagnetic Ability for Periodontal Regeneration

2018 ◽  
Vol 19 (11) ◽  
pp. 3604 ◽  
Author(s):  
Simone Sprio ◽  
Elisabetta Campodoni ◽  
Monica Sandri ◽  
Lorenzo Preti ◽  
Tobias Keppler ◽  
...  
Keyword(s):  
Cell Fate ◽  
Alveolar Bone ◽  
Tape Casting ◽  
Periodontal Regeneration ◽  
Dental Tissue ◽  
Hybrid Scaffold ◽  
Dental Tissues ◽  
Biomineralization Process ◽  
Direct Cell

The regeneration of dental tissues is a still an unmet clinical need; in fact, no therapies have been completely successful in regenerating dental tissue complexes such as periodontium, which is also due to the lack of scaffolds that are able to guide and direct cell fate towards the reconstruction of different mineralized and non-mineralized dental tissues. In this respect, the present work develops a novel multifunctional hybrid scaffold recapitulating the different features of alveolar bone, periodontal ligament, and cementum by integrating the biomineralization process, and tape casting and electrospinning techniques. The scaffold is endowed with a superparamagnetic ability, thanks to the use of a biocompatible, bioactive superparamagnetic apatite phase, as a mineral component that is able to promote osteogenesis and to be activated by remote magnetic signals. The periodontal scaffold was obtained by engineering three different layers, recapitulating the relevant compositional and microstructural features of the target tissues, into a monolithic multifunctional graded device. Physico-chemical, morphological, and ultrastructural analyses, in association with preliminary in vitro investigations carried out with mesenchymal stem cells, confirm that the final scaffold exhibits a good mimicry of the periodontal tissue complex, with excellent cytocompatibility and cell viability, making it very promising for regenerative applications in dentistry.

Sign in / Sign up

Export Citation Format

Share Document