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)

The aim of this study was to perform a systematic comparison of two widely used osteosarcoma cell lines and ascertain their relevance as experimental models for investigating osteoblast function. We have therefore compared growth, differentiated cell function, integrin expression and adhesive profiles of MG-63, HOS TE85, and human bone derived cells. Both osteosarcoma cell lines proliferated more rapidly than osteoblast-like cells with HOS cells exhibiting the shortest doubling time. HOS cells expressed higher levels of alkaline phosphatase than MG-63 cells under basal conditions but only MG-63 cells showed the increased enzyme activity following 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) administration, which is characteristic of bone derived cells. Osteocalcin was not detected in supernatants from any cells under basal conditions but levels produced by MG-63 cells on addition of 1,25(OH)2D3 were comparable with those of osteoblast-like cells. alpha 1, alpha 2, alpha 3, alpha 5, alpha V, and beta 1 integrin subunits were detected on all cells and there was no staining for alpha L, alpha M, beta 2, and beta 3. alpha 3 and beta 1 were the major subunits detected on MG-63, HOS, and bone derived cells but relative concentrations of other alpha subunits were dependent on cell type; alpha 4 and alpha 6 subunits could only be detected on osteosarcoma cell lines. Short term, serum-free cell adhesion assays showed that the three cell types adhered in a saturable manner to collagen I, fibronectin, and laminin.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Are MG-63 and HOS TE85 human osteosarcoma cell lines representative models of the osteoblastic phenotype? 787 86

We reviewed data on 42 postmenopausal women with established osteoporosis (forearm fracture or a low bone mass) who had been randomly treated for 1 year with either rectal salmon calcitonin (sCT), 100 IU daily (n = 25) or nasal sCT, 200 IU daily (n = 17) applying an estimation algorithm for bone loss rates. Both groups received a daily calcium supplement of 500 mg. A group of 18 age-matched women who received no treatment served as controls. The bone mineral content of the distal forearm (BMCarm) was measured every 3 months by single photon absorptiometry. The individual rates of change during the 1-year period were calculated by linear regression analysis (alpha BMCarm). Bone loss rates were estimated initially and after 1 year of therapy by measurements of serum alkaline phosphatase, plasma bone Gla protein, and fasting urinary hydroxyproline and calcium (both corrected for creatinine excretion) according to the estimation algorithm. Both administration forms revealed significant control group-corrected decreases in serum and urine markers of bone turnover of 15-40% (P < 0.05-0.01) and positive outcomes of 2% in alpha BMCarm (P < 0.01). The estimated effect on bone mass was expressed as the difference between the bone loss estimated after 1 year and initially (delta ESTBIO). A significant correlation was seen between alpha BMCarm and delta ESTBIO (r = 0.5, P < 0.0001). We conclude that the effect of sCT on bone can be followed up by biochemical markers for bone turnover, i.e., by an annual blood and fasting urine sample, applying an estimation algorithm for the rate of bone loss.
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PMID:Estimation of the effect of salmon calcitonin in established osteoporosis by biochemical bone markers. 792 94

Type 1 collagen is the major organic constituent of the bone: its synthesis is reflected by the serum levels of type 1 procollagen C-terminal propeptide (PICP), which is therefore considered an index of osteoblastic activity. Serum PICP along with other serum and urinary markers of bone metabolism were measured in 16 untreated premenopausal females affected by Graves' disease and also in 7 of them after attainment of euthyroidism by methimazole treatment. Before treatment PICP was higher than sex and age-matched controls (324.19 +/- 101.74 vs. 131.44 +/- 26.25 micrograms/l, p < 0.001). Osteocalcin, alkaline phosphatase, serum calcium and urinary excretions of calcium and hydroxyproline were significantly increased with respect to controls, whereas parathormone was lower. Treatment induced a significant decrease of PICP, as well as calcemia, calciuria and hydroxyprolinuria compared to pretreatment values, while osteocalcin and alkaline phosphatase did not significantly differ. Non parametric correlation analysis showed positive correlation of free T3 and PICP (rs = 0.73, p < 0.005), osteocalcin and alkaline phosphatase; PICP was also significantly correlated with osteocalcin and alkaline phosphatase. Our data suggest that hyperthyroidism due to Graves' disease causes an increase of serum concentrations of PICP, which decrease after attainment of euthyroidism. The differences between PICP and BGP as markers of bone synthesis need to be further clarified.
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PMID:Increased serum levels of carboxyterminal propeptide of type 1 collagen (PICP) in hyperthyroidism. 795 10

The effects of recombinant human bone morphogenetic protein 2 (rhBMP-2) on osteochondrogenesis were examined in high-density cultures of periosteum-derived cells, which have the potential to differentiate into bone and hypertrophic cartilage in vitro. Proliferation of these cells was inhibited by treatment with rhBMP-2. The time course for alkaline phosphatase (ALP) expression was shortened and the mineralization of the culture was increased by supplementation with rhBMP-2. These stimulatory effects of rhBMP-2 were observed at doses of 10-100 ng/m. Bone Gla protein (BGP) was immunocytochemically detectable earlier in the culture treated with rhBMP-2, and the BGP-positive layer of the rhBMP-2-treated cultures was thicker than that of the control cultures. On the other hand, there was no difference in uronic acid content or the time course of alpha 1(II) collagen mRNA expression between the rhBMP-2-treated and the control cultures. These results indicate that rhBMP-2 shortens the time course of osteogenesis and increases the amount of bone formation, whereas chondrogenesis remains unaffected.
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PMID:Bone morphogenetic protein 2 stimulates osteogenesis but does not affect chondrogenesis in osteochondrogenic differentiation of periosteum-derived cells. 797 2

Osteocalcin or bone Gla protein (BGP) is secreted by osteoblasts, and its serum concentration is elevated in a number of conditions with high bone turnover. A comparison of serum osteocalcin with total (TALP) and bone specific alkaline phosphatase (BALP) and urinary hydroxyproline/creatinine (OHP/Cr ratio) was performed in 13 patients with active Paget's disease of bone. BGP did not correlate significantly with either BALP or TALP, but did show a significant correlation with OHP/Cr ratio (r = 0.76; P < 0.01). BGP does not appear to be as sensitive a marker as BALP or TALP in Paget's disease.
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PMID:Comparison of serum osteocalcin with total and bone specific alkaline phosphatase and urinary hydroxyproline:creatinine ratio in patients with Paget's disease of bone. 797 96

The collagen crosslinks, pyridinoline (Pyr) and deoxypyridinoline (D-Pyr), were recently identified as potential markers of the rate of bone resorption. To determine whether urinary concentrations of Pyr and D-Pyr might provide an early warning of bone metastases in patients being monitored for cancer of the prostate, we compared these two newer parameters with the conventional indicators, that is, the serum concentrations of Bone Gla protein (BGP: osteocalcin) and alkaline phosphatase (ALP), in patients with prostate cancer with and without bone metastases vs. those of age-matched patients with benign prostatic hyperplasia (BPH). Urinary excretion of these compounds, expressed as a ratio to urinary creatinine (mg/dl), was determined by high performance liquid chromatography (HPLC) in 23 patients with prostate cancer (16 with bone metastases and 7 without bone metastases) and in 23 patients with BPH. The mean values of urinary Pyr and D-Pyr; 65.02 +/- 38.16 pmol/mumol of creatinine and 8.87 +/- 7.01 pmol/mumol of creatinine and 8.87 +/- 7.01 pmol/mumol of creatinine, respectively, for patients with bone metastases of prostate cancer were significantly higher than those for patients without bone metastases of prostate cancer (27.43 +/- 10.29 pmol/mumol of creatinine and 4.24 +/- 1.88 pmol/mumol of creatinine) or for patients with BPH (25.58 +/- 7.54 pmol/mumol of creatinine and 3.52 +/- 1.07 pmol/mumol of creatinine). Among these three groups of patients, there were statistically significant (Pyr: P = 0.0001, D-Pyr: P = 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Assay of urinary pyridinoline and deoxypyridinoline as potential markers of the rate of bone resorption: usefulness of urinary pyridinoline and deoxypyridinoline in patients with prostate cancer with bone metastases]. 799 Mar

Serum osteocalcin has been found to correlate with bone formation. However, present literature gives only limited data on osteocalcin and bone histomorphometry in patients undergoing peritoneal dialysis. This study assessed serum osteocalcin, dialysate osteocalcin, peritoneal clearance of osteocalcin (Clp-osteocalcin) and mass transfer of osteocalcin (MTp-osteocalcin), and evaluated relationships between these values and bone histomorphometry. Eighteen patients were treated by continuous ambulatory peritoneal dialysis (CAPD). Bone biopsies, serum and dialysate osteocalcin, serum levels of parathyroid hormone, alkaline phosphatase, aluminum, phosphate, Ca2+ and vitamin D3 metabolites were measured at the start and in 10 of the patients a year later. Serum osteocalcin was found to be elevated. Osteocalcin was detected in the dialysate resulting in significant values of Clp-osteocalcin and MTp-osteocalcin. Serum and dialysate levels of osteocalcin correlated significantly (r = 0.66, P < 0.001) and like MTp-osteocalcin with serum levels of alkaline phosphatase and PTH. Histomorphometry showed that osteitis fibrosa was the predominant bone disease detected. Serum concentration of osteocalcin correlated with osteoid thickness, eroded and osteoclast surfaces, aluminum staining, and some of the bone dynamic parameters. Dialysate osteocalcin, MTp-osteocalcin, PTH and alkaline phosphatase correlated with practically the same histomorphometric parameters as serum osteocalcin. No correlations were seen between Clp-osteocalcin and any histomorphometric parameters. Serum osteocalcin was elevated above the normal range, and significant positive correlations between serum osteocalcin and bone formation parameters were found. Serum osteocalcin correlated with almost the same histomorphometric parameters as PTH. Thus, serum levels of PTH and osteocalcin gave additional information to one another as non-invasive parameters in this group of patients.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Osteocalcin: a non-invasive index of metabolic bone disease in patients treated by CAPD. 799 5

The role of interleukin-6 in the bone microenvironment is controversial. We studied the effect of recombinant human interleukin-6 (rhIL-6) administration on bone metabolism in 10 adult female rhesus monkeys (age 12-27 years). Monkeys received rhIL-6 (15 micrograms/kg/day) daily by subcutaneous injection for 28 days. Serum alkaline phosphatase, osteocalcin, and 24 h urinary calcium excretion were determined before, during (at weeks 2 and 4), and after (at week 6) treatment. Transilial biopsies (right and left) were obtained before treatment was initiated and just after the final (28th) dose at week 4. The serum alkaline phosphatase significantly increased at 2 and 4 weeks of rhIL-6 administration. Osteocalcin and urinary calcium excretion significantly decreased at week 2. Upon treatment with rhIL-6 significant reductions in OS/BS and Ob.S/BS were observed without changes in other static histomorphometry parameters. The reductions in urinary calcium excretion, serum osteocalcin, and the static bone parameters are consistent with an IL-6 induced reduction in bone formation or turnover. Whether this pharmacologic effect is relevant at the physiologic level remains to be determined.
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PMID:Effects of recombinant human interleukin-6 administration on bone in rhesus monkeys. 799 21

Inflammatory bowel disease (Crohn's disease and ulcerative colitis) is associated with decreased bone mineral density and increased risk of osteoporosis. However, the pathogenesis of this bone loss is not yet fully understood. In the present study we measured lumbar bone mineral density (by dual photon absorptiometry), serum levels of parathyroid hormone (PTH) and vitamin D metabolites, and serum markers of bone turnover (alkaline phosphatase and osteocalcin) in 15 patients with Crohn's disease and in 4 patients with ulcerative colitis. The median duration of the disease was 4 years and the median lifetime steroid dose was 10g of prednisone. We compared our results to a control group of 19 normal persons, who were matched for age and sex to the patients. We found that lumbar bone density was reduced by 11% in patients compared with control persons (Z-score -0.6 +/- 0.6 versus -0.1 +/- 0.8; p < 0.05). In patients, the serum levels of PTH, 25-hydroxyvitamin D3, and calcitriol (1,25(OH)2D3) were significantly reduced compared with control persons. Serum alkaline phosphatase activity (AP) was significantly higher in the patients and was inversely related to lumbar bone density. Osteocalcin values were not different between patients and control persons. There was also no difference in serum levels of calcium between the two groups, whereas phosphorus levels were higher in patients. We conclude that malabsorption of calcium was not a primary cause of bone loss in our patients, because we did not find secondary hyperparathyroidism. Accordingly, we did not find a severe vitamin D deficiency, since 25-hydroxyvitamin D3 levels were within the normal range.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Bone mineral density and calcium regulating hormones in patients with inflammatory bowel disease (Crohn's disease and ulcerative colitis). 800 8

Phenotypic responses of rat calvarial osteoblast-like cells (RCOB) were evaluated on commercially pure titanium (cpTi) surfaces when cultured at high density (5100 cells/mm2). These surfaces were prepared to three different clinically relevant surface preparations (1-micron, 600-grit, and 50-microns-grit sand-blast), followed by sterilization with either ultraviolet light, ethylene oxide, argon plasma-cleaning, or routine clinical autoclaving. Osteocalcin and alkaline phosphatase, but not collagen expression, were significantly affected by surface roughness when these surfaces were altered by argon plasma-cleaning. In general, plasma-cleaned cpTi surfaces demonstrated an inverse relationship between surface roughness and phenotypic markers for a bone-like response. On a per-cell basis, levels of the bone-specific protein, osteocalcin, and the enzymatic activity of alkaline phosphatase were highest on the smooth 1-micron polished surface and lowest on the roughest surfaces for the plasma-cleaned cpTi. Detectable bone cell expression can be altered by clinically relevant surfaces prepared by standard dental implant preparation techniques.
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PMID:Bone cell expression on titanium surfaces is altered by sterilization treatments. 800 33


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