Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.3.1 (alkaline phosphatase)
 47,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In an attempt to reduce complications in cases of severe open fracture, we developed a bio-artificial periosteum composed of osteogenic cells and collagen sponge. In the present study, we evaluated the osteogenic potential of the bio-artificial periosteum in vivo and in vitro. After 4-week incubation in vitro, the bio-artificial periosteum had high alkaline phosphatase activity and osteocalcin content. Moreover, energy dispersive X-ray analysis revealed numerous crystal structures consisting of P and Ca on the surface of the bio-artificial periosteum. Using a rat model for severe bone injury, we examined the bone formation process in defect sites covered with the bio-artificial periosteum. New bone formation occurred in the central part of the bone defect as well as at the bone edge. We conclude that by using the bio-artificial periosteum, the fracture site benefited from an improved osteogenic environment. These results indicate that a clinical trial to further evaluate this technique should be conducted.
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PMID:Bio-artificial periosteum for severe open fracture--an experimental study of osteogenic cell/collagen sponge composite as a bio-artificial periosteum. 1591 94

Chronic Caffey's disease in an uncommon condition in children is characterized by an acute inflammatory reaction in the periosteum along with systemic disturbances. A 30 months old boy was reported in the pediatric unit of BSMMU, Dhaka about two and half years back with the complaints of multiple painful soft tissue swelling in different parts of the body since birth and delay in growth and development. The child was found well and alert, moderately pale, febrile with hard, tender swelling of mandible on both sides. There were multiple swellings over the right arm, forearm, both thighs and bowing of the lower limbes. Investigations revealed normal serum calcium and phosphate level with mild elevation of alkaline phosphatase. Radiological findings showed periosteal new bone formation in mandible and long bones. There was diaphyseal expansion of the long bones with expansion of the ribs anteriorly. He was diagnosed as a case of chronic caffey's disease on the basis of history, clinical examination and investigation.
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PMID:Chronic Caffey's disease: an uncommon entity in children. 1605 12

Hypoestrogenic states escalate bone loss in animals and humans. This study evaluated the effects of the amount and ratio of dietary n-6 and n-3 polyunsaturated fatty acids (PUFAs) on bone mineral in 3-month-old sexually mature ovariectomized (OVX) Sprague-Dawley rats. For 12 weeks, the rats were fed either a high-PUFA (HP) or a low-PUFA (LP) diet with a ratio of n-6/n-3 PUFAs of 5:1 (HP5 and LP5) or 10:1 (HP10 and LP10). All diets (modified AIN-93G) provided 110.4 g/kg of fat from safflower oil and/or high-oleate safflower oil blended with n-3 PUFAs (DHASCO oil) as a source of docosahexaenoic acid (DHA). Fatty acid analyses confirmed that the dietary ratio of 5:1 significantly elevated the amount of DHA in the periosteum, marrow and cortical and trabecular bones of the femur. Dual-energy X-ray absorptiometry measurements for femur and tibia bone mineral content (BMC) and bone mineral density showed that the DHA-rich diets (HP5 and LP5) resulted in a significantly lower bone loss among the OVX rats at 12 weeks. Rats fed the LP diets displayed the lowest overall serum concentrations of the bone resorption biomarkers pyridinoline (Pyd) and deoxypyridinoline, whereas the bone formation marker osteocalcin was lowest in the HP groups. Regardless of the dietary PUFA content, DHA in the 5:1 diets (HP5 and LP5) preserved rat femur BMC in the absence of estrogen. This study indicates that the dietary ratio of n-6/n-3 PUFAs (LP5 and HP5) and bone tissue concentration of total long-chain n-3 PUFAs (DHA) minimize femur bone loss as evidenced by a higher BMC in OVX rats. These findings show that dietary DHA lowers the ratio of 18:2n-6 (linoleic acid)/n-3 in bone compartments and that this ratio in tissue correlates with reduced Pyd but higher bone alkaline phosphatase activity and BMC values that favor bone conservation in OVX rats.
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PMID:Dietary ratio of n-6/n-3 PUFAs and docosahexaenoic acid: actions on bone mineral and serum biomarkers in ovariectomized rats. 1610 59

Evidence has accumulated that periosteal cells have a great potential to regenerate bone. We have demonstrated that cultured periosteum (CP) in membrane form is an effective device to regenerate alveolar bone. To increase the availability of CP in a clinical environment, an effective cryopreservation protocol for CP has been developed. In this study, three different cryoprotectants (Me(2)SO, glycerol, and ethylene glycol) were used. The effect on cell viability of pre-incubation temperature, pre-incubation time, and agitation during incubation was investigated. Samples were stored at -196 degrees C for 10 days. Cell viability was assessed by a colorimetric cell viability assay using a tetrazolium salt, and the assay results were confirmed by confocal laser scanning microscopy after staining with a combination of calcein AM and ethidium homodimer-1. The activity of the cells after thawing was assessed by alkaline phosphatase assay. To assess the osteogenic potential of cryopreserved CP, the CP was grafted to calvarial defects in athymic rats. The greatest cell viability was obtained in the group equilibrated at 37 degrees C for 30 min with Me(2)SO, under agitation, showing 63.3 +/- 10.5% recovery. After cryopreservation, the cell growth of surviving cells was identical when Me(2)SO was used as a cryoprotectant. Alkaline phosphatase (ALP) activity was maintained in the groups cryopreserved with Me(2)SO and glycerol. The transplantation experiment showed that the calvarial defects were completely closed by grafting cryopreserved CP, which demonstrates that the osteogenic property of CP was well maintained. An efficient cryopreservation protocol for CP has been developed and this will provide a convenient and effective treatment option for bone regeneration in clinics.
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PMID:Cryopreservation of cultured periosteum: effect of different cryoprotectants and pre-incubation protocols on cell viability and osteogenic potential. 1636 Jun 51

Extant chondrichthyans possess a predominantly cartilaginous skeleton, even though primitive chondrichthyans produced bone. To gain insights into this peculiar skeletal evolution, and in particular to evaluate the extent to which chondrichthyan skeletogenesis retains features of an osteogenic programme, we performed a histological, histochemical and immunohistochemical analysis of the entire embryonic skeleton during development of the swell shark Cephaloscyllium ventriosum. Specifically, we compared staining properties among various mineralizing tissues, including neural arches of the vertebrae, dermal tissues supporting oral denticles and Meckel's cartilage of the lower jaw. Patterns of mineralization were predicted by spatially restricted alkaline phosphatase activity earlier in development. Regarding evidence for an osteogenic programme in extant sharks, a mineralized tissue in the perichondrium of C. ventriosum neural arches, and to a lesser extent a tissue supporting the oral denticle, displayed numerous properties of bone. Although we uncovered many differences between tissues in Meckel's cartilage and neural arches of C. ventriosum, both elements impart distinct tissue characteristics to the perichondral region. Considering the evolution of osteogenic processes, shark skeletogenesis may illuminate the transition from perichondrium to periosteum, which is a major bone-forming tissue during the process of endochondral ossification.
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PMID:Skeletogenesis in the swell shark Cephaloscyllium ventriosum. 1745 31

Secondary cartilages including mandibular condylar cartilage have unique characteristics. They originate from alkaline phosphatase (ALP)-positive progenitor cells of the periosteum, and exhibit characteristic modes of differentiation. They also have a unique extracellular matrix, and coexpress type I, II and X collagens. We have previously shown that there is a total absence of secondary cartilages in Runx2-deficient (Runx2-/-) mice. To clarify whether Runx2 is essential for chondrocytic differentiation of secondary cartilages, we performed an organ culture system using mandibular explants derived from Runx2-/- mice at embryonic day 18.0. Since mRNA for bone morphogenetic protein 2 (BMP2) was strongly expressed in osteoblasts of condylar anlagen in wild-type mice, and was down-regulated in those of Runx2-/- mice, we chose to investigate BMP2 effects on secondary cartilage formation. Condensed mesenchymal cells of mandibular condylar anlagen in precultured explants were ALP-positive and expressed type I collagen and Sox9. After culture with recombinant human (rh) BMP2, chondrocytic cells showing ALP activity and expressing Sox5, Sox9, and type I and II collagens, appeared from mesenchymal condensation. This expression profile was comparable with the reported pattern of chondrocytes in mouse secondary cartilages. However, chondrocyte hypertrophy was not observed in the explants. These findings indicate that BMP2 partially rescued chondrocyte differentiation but not chondrocyte hypertrophy in secondary cartilage formation in Runx2-/- mice. Runx2 is required for chondrocyte hypertrophy in secondary cartilage formation, and it is likely that BMP2, which is abundantly secreted by osteoblasts in condylar anlagen, contributes to the early process of secondary cartilage formation.
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PMID:Bone morphogenetic protein rescues the lack of secondary cartilage in Runx2-deficient mice. 1755 46

We aimed to histologically elucidate whether bioresorbable plates (DeltaSystem) can induce cortical bone formation, which is essential for long-lasting bone augmentation. Standardized bone defects in rat calvariae were covered with a convexly-shaped DeltaSystem plate, and then processed for histological observations. At 1 week, alkaline phosphatase-positive osteoblasts were seen in the newly-formed bone extending from the cavity's bottom, indicating accelerated osteogenesis. A thick layer of soft connective tissue positive for periostin, a hallmark of periosteum, covered this new bone. At 2 weeks, a spongy bone had filled the cavity up to half its height. The inner layer of the soft tissue facing the spongy bone revealed abundant periostin and osteopontin, and had many tartrate-resistant acid phosphatase-positive osteoclasts. At 4 weeks, this layer had given rise to thin new bony matrices without relation to the spongy bone arising from the cavity. These bone matrices had been thickened by 8 weeks, and turned into a thick cortical bone outlining the regenerated bone at 12 weeks. Thus, our study has provided histological evidences of cortical osteogenesis when DeltaSystem plates are used for bone augmentation procedures.
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PMID:Histochemical examinations on cortical bone regeneration induced by thermoplastic bioresorbable plates applied to bone defects of rat calvariae. 1787 2

Radiation-induced craniofacial bone growth inhibition is a consequence of therapeutic radiation in the survivors of pediatric head and neck cancer. Previously, the infant rabbit orbitozygomatic complex (OZC) was established as a reliable animal model. The purpose of this study was to develop a cell culture model from the rabbit OZC to study the effects of radiation in the craniofacial skeleton. Infant (7-week-old) New Zealand white rabbits were used in this study. Periostea from both OZC were harvested in sterile conditions, introduced into cell culture by way of sequential digestion, and subcultured at confluence. Cultures were analyzed for cellular proliferation (methylthiazoletetrazolium assay), alkaline phosphatase activity, collagen type I expression, and mineralization. Electron microscopy was performed to reveal the in vitro ultrastructure. Subsequently, rabbits were irradiated with sham or 15 Gy radiation, and cell cultures were developed and analyzed for cell numbers. Cell cultures, grown from OZC periostea, expressed osteoblast-like phenotype, with high alkaline phosphatase activity, collagen type 1 expression, and mineralization in an osteogenic environment. Electron microscopy confirmed the characteristic ultrastructural features of osteogenesis in vitro. Finally, significantly (P < 0.01) fewer cells were obtained from animals treated with 15 Gy radiation compared with those from control animals.A primary cell culture with osteoblast-like cellular phenotype was developed from infant rabbit OZC periosteum. This cell culture system responded to in vivo administered radiation by a significant decrease in cell numbers. This in vitro model will be subsequently used to study the cellular mechanisms of radiation and radioprotection in craniofacial osteoblast-like cells.
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PMID:An in vitro model of radiation-induced craniofacial bone growth inhibition. 1791 79

The development is expected of scaffold biomaterials that feature a shape-maintaining property in addition to high porosity and large pores that cells can easily invade. To develop a new biodegradable scaffold biomaterial reinforced with a frame, synthesized carbonate apatite (CO3Ap) was mixed with neutralized collagen gel, and the CO3Ap-collagen mixtures were lyophilized into sponges in a porous hydroxyapatite (HAp) frame ring. X-ray diffraction and Fourier transform infrared spectroscopy (FT-IR) analyses together with chemical analysis indicated that the synthesized CO3Ap had a crystalline nature and a chemical composition similar to that of bone. Scanning electron microscope (SEM) observation showed that the CO3Ap-collagen sponge had a sui pore size for cell invasion. In proliferation and differentiation experiments with osteoblasts, alkaline phosphatase and osteopontin activity were clearly detected. When these sponge-frame complexes with bone morphogenic protein (rh-BMP2) were implanted beneath the periosteum cranii of rats, significant new bone was created at the surface of the periosteum cranii after 4 weeks of implantation. These reinforced CO3Ap-collagen sponges with rh-BMP2 are expected to be used as hard tissue scaffold biomaterials for the therapeutic purpose of the rapid cure of bone defects.
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PMID:Acceleration of bone formation with BMP2 in frame-reinforced carbonate apatite-collagen sponge scaffolds. 1807 50

Mesenchymal stem cells (MSCs) reside in many types of tissue and are able to differentiate into various functional cells including osteoblasts. Recently, adipose tissue-derived MSCs (AMSCs) have been shown to differentiate into many lineages, and they are considered a source for tissue regeneration. The purpose of this study was to compare the osteogenic differentiation capability of MSCs from bone marrow (BMSCs), MSCs from periosteum (PMSCs), and AMSCs using in vitro culture and in vivo implantation experiments. We harvested these MSCs from 7-week-old rats. The cells were seeded and cultured for 7 days in primary culture to assay a colony-forming unit. The frequency of the unit was the smallest in the BMSCs (P < 0.001). After primary culture, subculture was performed under osteogenic differentiation conditions for 1 and 2 weeks to detect mineralization as well as the bone-specific proteins of alkaline phosphatase and osteocalcin as osteogenic markers. BMSCs and PMSCs showed distinct osteogenic differentiation capability in comparison with other MSCs (P < 0.001). For the in vivo assay, composites of these cells and hydroxyapatite ceramics were subcutaneously implanted into syngeneic rats and harvested after 6 weeks. Micro-computed tomographic (CT) and histological analyses demonstrated that new bone formation was detected in the composites using BMSCs and PMSCs, although it was hard to detect in other composites. The CT analyses also demonstrated that the bone volume of BMSC composites was more than that of AMSC composites (P < 0.001). These results indicate that BMSCs and PMSCs could be ideal candidates for utilization in practical bone tissue regeneration.
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PMID:Comparison of osteogenic ability of rat mesenchymal stem cells from bone marrow, periosteum, and adipose tissue. 1830 86


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