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

Methanol extract (MeOH), n-hexane (Hx), chloroform (CHCl3), ethyl acetate (EA), butanol (BuOH) and aqueous (H2O) fractions of Eucommiae Cortex including geniposidic acid (GA), geniposide (GP) and aucubin (AU) were tested for their therapeutic efficacy on osteoporosis. The contents of GA, GP and AU in the cortex and leaf of Eucommia ulmoides Oliver were quantified by HPLC. The effect of Eucommiae Cortex on the induction of growth hormone (GH) release was studied by using rat pituitary cells. The proliferation of osteoblast-like cells increased by herbal extracts was assayed using a tetrazolium (MTT), alkaline phosphatase (ALP) activity, and [3H]-proline incorporation assays. The inhibition of osteoclast was studied by using the coculture of mouse bone marrow cells and ST-2 cells. As a result, the GA, GP and AU were present in the cortex more than in the leaf of E. ulmoides Oliver. The MeOH (1 mg/mL), Hx, CHCl3 and EA fractions (each 20 microg/mL) had potent induction of GH release. The CHCl3 exhibited the potent proliferation of osteoblasts. The AU, GP and GA were increased proliferation of osteoblasts. In addition, GA (IC50: 4.43 x 10(-7) M), AU and GP were significantly inhibited proliferation of osteoclast. In summary, it is thought that the components in a part of the fractions of Eucommiae Cortex participate in each step of mechanism for activating osteoblast to facilitate osteogenesis, and suppress osteoclast activity to inhibit osteolysis.
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PMID:Effects of Eucommiae Cortex on osteoblast-like cell proliferation and osteoclast inhibition. 1466 59

The injurious effects of reactive oxygen species on osteoblasts and the potential protective role played by green tea polyphenols (GtPP) were investigated using primarily cultured rat calvarial osteoblasts. Oxidative stress was induced in cultured osteoblasts, either by adding 100 mmol/L H2O2 or by the action of 40 U/L xanthine oxidase (XO) in the presence of xanthine (250 micromol/L). After incubation, the cellular viability, function and morphology were evaluated. Both treatments produced a significant reduction in osteoblast viability, as assessed by a two-colored fluorescence staining method combined with flow cytometric analysis and MTT assay. A significant reduction in the alkaline phosphatase activity was observed after H2O2 addition, whereas XO did not have the same effect. On the microscopic observations, the morphological changes and intracellular ultrastructural damages were remarkably induced by both treatments. The H2O2-induced alterations were prevented by pre-incubating the osteoblasts with 200 microg/ml GtPP for 1 h. When the oxidative stress was induced by XO, the cellular viability and morphology was also maintained at the same polyphenol concentration. These results demonstrate that GtPP can act as a biological antioxidant in a cell culture experimental model and protect cells from oxidative stress-induced toxicity.
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PMID:Protective effects of green tea polyphenol against reactive oxygen species-induced oxidative stress in cultured rat calvarial osteoblast. 1470 19

Aseptic loosening and osteolysis are currently the most common causes of failure of total joint replacements. Osteolysis is initiated by a macrophage response to wear debris, resulting in localized, osteoclastic peri-implant bone loss. We have previously inhibited osteoclast-mediated bone resorption in a canine total hip arthroplasty model using oral bisphosphonate therapy. Based on serendipitous observations from our canine study, we hypothesized that bisphosphonates have an anabolic effect on osteoblasts, in a manner distinct from their inhibitory effect on osteoclastic bone resorption. We studied the anabolic effects of two FDA-approved bisphosphonates (alendronate and risedronate) on two in vitro models: a primary human trabecular bone cell culture and the MG-63 osteoblast-like cell line. Following treatment with bisphosphonates at varying concentrations and time periods, cells were assayed for proliferation effects and results were quantified using the methods of direct cell count, and the colorimetric MTT (3-dimethylthiazol-2,5-diphenyltetrazolium bromide) assay at 24, 48, and 72 h. The effect of bisphosphonates on the maturation of osteoblasts were tested with alkaline phosphatase bioassay and reverse transcription-polymerase chain reaction for markers of osteoblast differentiation. Results from both the primary human trabecular bone cell culture and the MG-63 osteoblast-like cell line showed that both bisphosphonates significantly increased the cell number over controls, attaining peak levels at a concentration of 10(-8)M. Alkaline phosphatase activity was also increased, representing earlier commitment of osteoprogenitor cells towards the osteoblastic phenotype. Bisphosphonates also enhanced gene expression of BMP-2, Type I collagen and osteocalcin. In summary, bisphosphonates, aside from their role as inhibitors of osteoclastic bone resorption, are promoters of osteoblast proliferation and maturation.
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PMID:Osteoblast proliferation and maturation by bisphosphonates. 1504 1

Response of different types of cells on materials is important for the applications of tissue engineering and regenerative medicine. It is recognized that the behavior of the cell adhesion, proliferation, and differentiation on materials depends largely on surface characteristics such as wettability, chemistry, charge, rigidity, and roughness. In this study, we examined the behavior of MG63 osteoblast-like cells cultured on a polycarbonate (PC) membrane surfaces with different micropore sizes (0.2-8.0 microm in diameter). Cell adhesion and proliferation to the PC membrane surfaces were determined by cell counting and MTT assay. The effect of surface micropore on the MG63 cells was evaluated by cell morphology, protein content, and alkaline phosphatase (ALP) specific activity. It seems that the cell adhesion and proliferation were progressively inhibited as the PC membranes had micropores with increasing size, probably due to surface discontinuities produced by track-etched pores. Increasing micropore size of the PC membrane results in improved protein synthesis and ALP specific activity in isolated cells. There was a statistically significant difference (P<0.05) between different micropore sizes. The MG63 cells also maintained their phenotype under conditions that support a round cell shape. RT-PCR analysis further confirmed the osteogenic phenotype of the MG63 cells onto the PC membranes with different micropore sizes. In results, as micropore size is getting larger, cell number is reduced and cell differentiation and matrix production is increased. This study demonstrated that the surface topography plays an important role for phenotypic expression of the MG63 osteoblast-like cells.
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PMID:Response of MG63 osteoblast-like cells onto polycarbonate membrane surfaces with different micropore sizes. 1512 May 16

By culturing bone marrow mesenchymal stem cells of rabbits with fibrin glue in vitro, the biocompatibility of fibrin glue was investigated to study whether this material can be used as scaffolds in bone tissue engineering. After 2-months old New Zealand rabbits had been anesthetized, about 4-6 ml of bone marrow were aspirated from rabbit femoral trochanter. The monocytes suspension was aspirated after bone marrow was centrifuged with lymphocyte separating medium and cultured primarily. Then the cells were divided into two groups: one was cultured with complete medium and the other with induced medium. The cells of the two groups were collected and inoculated to the culture plate containing fibrin glue. In the control group, cells were inoculated without fibrin glue. The implanted cells and materials were observed at different stages under a phase-contrast microscope and scanning electron microscope. MTT and alkaline phosphatase (ALP) were measured. Bone marrow mesenchymal stem cells grew on the surface of fibrin glue and adhered to it gradually. Cells light absorption value (A value) and the ALP content showed no significant difference. Fibrin glue had no inhibitory effect on cell morphology, growth, proliferation and differentiation. It has good biocompatibility and can be used as scaffold materials for bone marrow mesenchymal stem cells in bone tissue engineering.
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PMID:Biocompatibility studies on fibrin glue cultured with bone marrow mesenchymal stem cells in vitro. 1531 46

In the present study, the functions of rat calvaria osteoblasts on baicalin-modified poly(D,L-lactic acid) (PDLLA) films were investigated in vitro. The surface characteristics of surfaces (both modified and control) were investigated by water contact angle measurement and electron spectroscopy for chemical analysis (ESCA). Cell morphologies on these surfaces were examined by scanning electron microscopy (SEM). Cell adhesion and proliferation were used to assess cell growth on the modified and control surfaces. The MTT assay was used to determine cell viability and alkaline phosphatase (ALP) activity was performed to evaluate differentiated cell function. Compared to control films, cell attachment of osteoblasts on baicalin-modified PDLLA film was significantly higher (P<0.05 and P<0.01) after 6 h and 8 h culture, and cell proliferation was also significantly greater (P<0.05 and P<0.01) at the end of 4th and 7th day, respectively. The MTT assay suggested that the cell viability of osteoblasts cultured on baicalin-modified PDLLA film was significantly higher (P<0.05) than that seeded on the control. Meanwhile, the ALP activity of osteoblasts cultured on modified films was also considerably enhanced (P<0.01) compared to that found on control. These results revealed that the biocompatibility PDLLA could be improved by surface modification with baicalin.
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PMID:Effects of baicalin-modified poly(D,L-lactic acid) surface on the behavior of osteoblasts. 1534 8

The biocompatibility of titania/hydroxyapatite (TiO(2)HA) composite coatings, at different ratio obtained by sol-gel process, was investigated studying the behavior of primary cultures of rat osteoblastic cells, isolated by femoral trabecular bone tissue. Moreover, the results have been compared with the response of human osteoblast-like MG63 cell line. Cytotoxicity of coatings was assessed by lactate dehydrogenase activity (LDH). The cellular behavior was analyzed by the cell proliferation (MTT test), cell morphology (SEM) and the biochemical markers evaluation of osteoblastic phenotype, such as alkaline phosphatase activity (ALP) and osteocalcin production. The results showed that TiO(2)/HA coatings have no toxic effects and seemed to be a good support for cell adhesion and proliferation. Moreover, these materials allowed the differentiation of osteoblasts, stimulating the expression of alkaline phosphatase activity. The responses of the primary rat osteoblasts and human osteoblast-like MG63 cell line grown onto these coatings were similar in terms of proliferation and ALP activity. Differences were found considering the osteocalcin production. The results show that these coatings, thanks to their chemical composition and the deposition technique, are very promising for the potential orthopedic and dental applications.
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PMID:In vitro response of primary rat osteoblasts to titania/hydroxyapatite coatings compared with transformed human osteoblast-like cells. 1534 68

Rat, rabbit and human bone marrow cells were cultured according to the method previously reported for cells of rat origin [1] and were exposed, or not (control), to corrosion products of a Co-Cr orthopaedic alloy as well as to metal salts containing Co2+, Cr3+ and Cr6+. Cells were cultured for 21 days and analysed for the following biochemical parameters: intracellular MTT reduction (i.e. cell viability/proliferation), alkaline phosphatase (ALP) activity and protein production. Morphological observations included both histochemistry (detection of ALP-positive cells, calcium and phosphate deposits) and scanning electron microscopy (SEM). Control cultures of rat and rabbit cells showed higher proliferation rates than human cells at the start of culture, but they all reached similar values on day 21. Protein production was parallel to cell proliferation. In contrast, ALP activity of rat cultures was much stronger than rabbit or human cultures. All cell types were able to develop the osteogenic phenotype in vitro.Co-Cr extract caused inhibitory effects on cell viability, on ALP activity and, to a lower extent, on protein production of all rat, rabbit and human cell cultures. Compared to rat and rabbit cultures, human cultures were the most sensitive to metal ions exposure.
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PMID:The use of rat, rabbit or human bone marrow derived cells for cytocompatibility evaluation of metallic elements. 1534 64

When studying the biocompatibility of orthopaedic biomaterials it is often necessary to discriminate between responses which show mild cytotoxicity. It is therefore essential to use a very sensitive index of toxicity. We have compared the sensitivity of four well-established indices of toxicity: total cell protein content, leakage of lactate dehydrogenase (LDH), reduced glutathione content and the MTT assay, with that of a novel index, alkaline phosphatase (ALP) activity. Comparisons were made by detecting nickel chloride toxicity in osteoblasts. ALP activity, the novel method, proved the most sensitive index of toxicity and it provides a convenient automated assay for assessing the interactions of materials with osteoblasts. The responses to nickel chloride and to aqueous extracts prepared from carbon fibre reinforced epoxy and polyetheretherketone (peek), two candidate materials for orthopaedic implants, were compared in primary and immortalized rat osteoblasts, and in primary human osteoblasts. Although the immortalized rat osteoblast cell line, FFC, was consistently the most sensitive cell type, the responses of the human cells and the FFC cell line were similar in terms of ALP activity throughout the range of nickel concentrations studied. Neither peek nor epoxy material extracts showed a significant decrease in the MTT or ALP responses in any of the three cell types. Our data suggest that immortalized rat osteoblasts may provide an in vitro model system for screening the biocompatibility of orthopaedic polymers.
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PMID:The response of primary rat and human osteoblasts and an immortalized rat osteoblast cell line to orthopaedic materials: comparative sensitivity of several toxicity indices. 1534 78

Three different microstructures were obtained on a titanium surface via immersion in HCl, H3PO4, or mixed acid of HNO3 and HF (HNO3/HF) solution. The microstructure and Rmax of the acid-treated surfaces were dependent on the acid type and immersion conditions. The growth rate of the osteogenic cell line MC3T3-E1 on each acid-treated sample, which was measured using MTT-formazan assay, was significantly higher than that of the standard which was ground with #400 SiC grit paper. Moreover, both the H3PO4 treated sample and the HNO3/HF-treated surface showed a tendency to enhance the alkaline phosphatase activity of MC3T3-E1 cells, which were grown on each acid-treated surface. These results suggest that the acid treatment of titanium is effective for the improvement of its osteocompatibility.
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PMID:Effect of microstructure of titanium surface on the behaviour of osteogenic cell line MC3T3-E1. 1534 15


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