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Background & Aims: Nutrition is one of the most important environmental factors affecting the formation of osteopenia. The purpose of this study was to investigate the effects of dietary changes on bone formation and bone resorption markers of postmenopausal women with vertebral osteopenia., Methods: In this study, 108 women with postmenopausal vertebral osteopenia were included. Patients were observed for a month to identify their regular nutritional status. Before intervention, blood and urine samples were taken from all patients. Then, 2-day food consumption records were taken and the patients were divided into 4 groups. Different types of diets (opposite of their regular diets) were prepared for these groups (1: control, 2: reduced-carbohydrate, 3: reduced-protein, 4: reduced-sodium) and followed for 3 months. At the end of follow-ups, blood and urine samples were taken again and changes in osteocalcin (OC) and N-terminal telopeptide (NTX) levels were examined., Results: According to biochemical analysis, there was a significant decrease (p < 0,001) in OC levels in reduced protein group and an increase (p > 0,05) in reduced carbohydrate group. When NTX levels were assessed, a significant decrease (p < 0.001) in the reduced carbohydrate group and a significant increase in the reduced protein group (p < 0.05) were found., Conclusion: Our findings show that reduced carbohydrate diet protected whereas, reduced protein diet negatively affected bone health. Osteopenic individuals were thought to be able to improve bone health and their quality of life by early dietary intervention., Competing Interests: Conflict of interest The authors declare no conflict of interest., (Copyright © 2020 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.)

The relationship between daily boron intake and osteocalcin-mediated osteoporosis was studied in boron-exposed postmenopausal women. It is known that boron and osteocalcin are important in bone metabolism, however the effect of boron in bone metabolism has not been fully discovered. The study was performed on 53 postmenopausal women aged 55-60 living in parts of Balikesir, Turkey, where the subjects are naturally exposed to high (≥1 mg/L) or low (<1 mg/L) boron concentration in drinking water. 24-h urine samples were collected from all participants and creatinine clearance was detected. Boron intake levels of the subjects whose clearance levels were between 80-124 mL/min were measured by inductively coupled plasma-optical emission spectrometry (ICP-OES) in urine samples. Serum osteocalcin levels of the subjects were measured by osteocalcin enzyme-linked immunosorbent assay (ELISA) kit. Osteocalcin polymorphism rs1800247 was detected using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Serum osteocalcin levels in boron-exposed postmenopausal women were significantly higher than that of control group (P ≤ 0.05) and the correlation between the serum osteocalcin level and rs1800247 polymorphism was not significant in both groups (P > 0.05). The differences in the distribution of osteocalcin genotypes and alleles in postmenopausal women were not significant between the boron exposed and the control groups (P > 0.05). Serum osteocalcin level in the CC genotype was significantly higher compared to the TC genotype in boron-exposed group (P ≤ 0.05). Our study suggests that daily boron intake of 1 mg/L may affect bone metabolism in postmenopausal women positively., (Copyright © 2018 Elsevier GmbH. All rights reserved.)

Recent research suggested a metabolic implication of osteocalcin (OCN) in e.g. insulin sensitivity or steroid production. We used an untargeted metabolomics approach by analyzing plasma and urine samples of 931 participants using mass spectrometry to reveal further metabolic actions of OCN. Several detected relations between OCN and metabolites were strongly linked to renal function, however, a number of associations remained significant after adjustment for renal function. Intermediates of proline catabolism were associated with OCN reflecting the implication in bone metabolism. The association to kynurenine points towards a pro-inflammatory state with increasing OCN. Inverse relations with intermediates of branch-chained amino acid metabolism suggest a link to energy metabolism. Finally, urinary surrogate markers of smoking highlight its adverse effect on OCN metabolism. In conclusion, the present study provides a read-out of metabolic actions of OCN. However, most of the associations were weak arguing for a limited role of OCN in whole-body metabolism.

The aim of this study was to analyze the presence of lithogenic metabolic factors in the blood and urine of patients with osteopenia versus osteoporosis. This is a cross-sectional study including 67 patients who were divided into two groups according to the presence of either osteopenia or osteoporosis as measured by bone densitometry: group 1-40 patients with osteopenia (22 men and 18 women) and group 2-27 patients with osteoporosis (13 men and 14 women). Metabolic studies were performed on the blood and urine; statistical analysis was performed comparing means and conducting linear correlation and multivariate analyses with SPSS. Statistical significance was considered to be p ≤ 0.05. The mean age of patients in group 1 was 52.9 ± 12.8 years versus 50.3 ± 11.4 in group 2; the difference was not statistically significant. In group 2, higher levels of osteocalcin, β-crosslaps, urinary calcium, fasting urine calcium/creatinine, 24 h urine calcium/creatinine and 24 h oxaluria were observed compared to group 1. In the multivariate analysis, only the β-crosslaps and urinary calcium were independently associated with osteoporosis. It would be advisable to determine the urinary calcium levels in patients with osteoporosis since altered levels may necessitate modifying the diagnostic and therapeutic approach to osteoporosis.

Purpose: To analyze the presence of phosphocalcic metabolism disorders in patients with osteopenia-osteoporosis without nephrolithiasis with respect to a control group., Methods: A cross-sectional study was conducted in patients with osteopenia-osteoporosis without nephrolithiasis (n = 67) in lumbar spine or femur and in a control group (n = 61) with no lithiasis or bone disorders. Blood bone markers, phosphocalcic metabolism, fasting urine, 24-h urine lithogenic risk factors, and densitometry were recorded in both groups. SPSS 20.0 was used for statistical analysis., Results: In comparison with the controls, significantly higher blood calcium (9.27 ± 0.36 vs. 9.57 ± 0.38, p = 0.0001), intact parathormone (45.6 ± 14.9 vs. 53.8 ± 18.9, p = 0.008), and alkaline phosphatase (61.9 ± 20.9 vs. 70.74 ± 18.9, p = 0.014) levels were found in patients with osteopenia-osteoporosis. In the 24-h urine test, citrate (1010.7 ± 647.8 vs. 617.6 ± 315.8, p = 0.0001) and oxalate (28.21 ± 17.65 vs. 22.11 ± 16.49, p = 0.045) levels were significantly lower in osteopenia-osteoporosis patients than in controls, with no significant difference in calcium (187.3 ± 106.9 vs. 207.06 ± 98.12, p = 0.27) or uric acid (540.7 ± 186.2 vs. 511.9 ± 167.06, p = 0.35) levels. Patients with osteopenia-osteoporosis had significantly higher levels of lithogenic risk factors associated with bone remodeling, including significantly increased β-crosslaps and osteocalcin values and higher β-crosslaps/osteocalcin ratios., Conclusion: Patients with osteopenia-osteoporosis without nephrolithiasis showed phosphocalcic metabolism disorders as well as lower urinary citrate and higher β-crosslaps/osteocalcin and fasting calcium/creatinine ratios, which would increase the risk of nephrolithiasis. Hence, prospective studies are warranted to evaluate the long-term risks.

Background: Estrogen deficiency in women and high-saturated fat, high-sucrose (HFS) diets have both been recognized as risk factors for metabolic syndrome. Studies on the combined actions of these 2 detrimental factors on the bone in females are limited., Objective: We sought to determine the interactive actions of estrogen deficiency and an HFS diet on bone properties and to investigate the underlying mechanisms., Methods: Six-month-old Sprague Dawley sham or ovariectomized (OVX) rats were pair fed the same amount of either a low-saturated-fat, low-sucrose (LFS) diet (13% fat calories; 15% sucrose calories) or an HFS diet (42% fat calories; 30% sucrose calories) for 12 wk. Blood, liver, and bone were collected for correspondent parameters measurement., Results: Ovariectomy decreased bone mineral density in the tibia head (TH) by 62% and the femoral end (FE) by 49% (P < 0.0001). The HFS diet aggravated bone loss in OVX rats by an additional 41% in the TH and 37% in the FE (P < 0.05). Bone loss in the HFS-OVX rats was accompanied by increased urinary deoxypyridinoline concentrations by 28% (P < 0.05). The HFS diet induced cathepsin K by 145% but reduced osteoprotegerin mRNA expression at the FE of the HFS-sham rats by 71% (P < 0.05). Ovariectomy significantly increased peroxisome proliferator-activated receptor γ mRNA expression by 136% and 170% at the FE of the LFS- and HFS-OVX rats, respectively (P < 0.05). The HFS diet aggravated ovariectomy-induced lipid deposition and oxidative stress (OS) in rat livers (P < 0.05). Trabecular bone mineral density at the FE was negatively correlated with rat liver malondialdehyde concentrations (R(2) = 0.39; P < 0.01)., Conclusions: The detrimental actions of the HFS diet and ovariectomy on bone properties in rats occurred mainly in cancellous bones and were characterized by a high degree of bone resorption and alterations in OS., (© 2016 American Society for Nutrition.)

Periodontal pathogens and/or inflammatory products from periodontitis participate in the development or progression of systemic diseases. In this context, periodontitis acts as a modifying factor to systemic health, including diabetes and cardiovascular diseases. Osteoporosis is an increasingly prevalent condition in our aging population and considered a risk factor for periodontal disease, but the effect of periodontitis on systemic bone homeostasis is unknown. We thus evaluated the effects of experimental periodontitis (EP) on systemic bone loss and the influence of estrogen deficiency in this context, using a mouse model of combined periodontitis and osteoporosis. Experimental periodontitis (EP) was induced by a ligature insertion around the mandibular first molars and Porphyromonas gingivalis infection. Three-dimensional microcomputed tomographic analyses performed 48days following infection revealed that EP and ovariectomy (OVX) induced a significantly higher femoral and mandibular bone loss compared to EP or OVX alone. EP alone did not induce systemic bone loss. In addition, the EP+OVX and EP groups showed significantly higher levels of tumor necrosis factor (TNF)-α than OVX and control groups at end point. These results suggest that periodontitis could be a risk factor for systemic bone loss, especially in post-menopausal women, and warrant further clinical investigations to confirm this association and propose adapted prophylactic and curative therapies., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Background/aim: There is a lack of data on the effects of prolactin on calcium metabolism and bone turnover in hyperprolactinemia of various origins. The aim of this study was to compare the influence of medicamentous and physiological hyperprolactinemia on bone turnover in female rats., Methods: Experimental animals (18 weeks old, Wistar female rats) were divided as follows: the group P - 9 rats, 3 weeks pregnant; the group M3-10 rats that were intramuscularly administrated sulpirid (10 mg/kg) twice daily for 3 weeks, the group M6 - 10 rats that were intramuscularly administrated with sulpirid (10 mg/kg) twice daily for 6 weeks, and age matched nulliparous rats as the control group: 10 rats, 18-week-old (C1) and 7 rats, 24 weeks old (C2). Laboratory investigations included serum ionized calcium and phosphorus, urinary calcium and phosphorous excretion, osteocalcin and serum procollagen type 1 N-terminal propeptide (P1NP)., Results: Experimental animals in the group P compared to the control group, displayed lower mean serum ionized calcium (0.5 +/- 0.2 vs 1.12 +/- 0.04 mmol/L; p < 0.001); higher mean serum phosphorus (2.42 +/- 0.46 vs 2.05 +/- 0.2 mmol/L; p < 0.05); increased urinary calcium (3.90 +/- 0.46 vs 3.05 +/- 0.58; p < 0.01) and significantly increased P1NP (489.22 +/- 46.77 vs 361.9 +/- 53.01 pg/mL; p < 0.001). Experimental animals in the group M3 had significantly decreased P1NP, compared to the contol group. Prolongated medicamentous hyperprolactinemia (the group M6) induced increased serum ionized calcium (1.21 +/- 0.03 vs 1.15 +/- 0.02 mmol/L; p < 0.001); decreased serum phosphorus (1.70 +/- 0.13 vs 1.89 +/- 0.32 mmol/L; p < 0.001); decreased osteocalcin and P1NP., Conclusions: Physiological hyperprolactinemia does not have such harmful effect on bone metabolism as medicamentous hyperprolactinemia. Chronic medicamentous hyperprolactinemia produces lower serum levels of bone formation markers. Assessment of bone turnover markers in prolongated medicamentous hyperprolactinemia provides an opportunity for earlier diagnosis of bone metabolism disturbances and should be considered as mandatory.

Objectives: To evaluate the effects of a combined oral contraceptive (COC) containing dienogest/oestradiol valerate (DNG/E2V) on bone mineral density (BMD) and on serum and urinary bone turnover markers in young, healthy, fertile women., Methods: At baseline and after three and six months of intake of the aforementioned COC, serum and urinary calcium, osteocalcin, urinary pyridinoline (PYD), and deoxypyridinoline (D-PYD) of 30 women aged 21 to 34 years were measured. At baseline and after six months, lumbar bone mineral density was determined by dual-energy X-ray absorptiometry (DEXA)., Results: Urinary levels of PYD and D-PYD were significantly lower at three and six months in comparison with basal values (p < 0.05). Serum calcium levels showed an increasing trend, which reached statistical significance after six months in comparison with basal values while urinary levels of calcium did not vary significantly. Serum osteocalcin levels were somewhat, but not significantly, lower during pill use in comparison with basal values. After six months, spinal BMD values did not differ significantly from basal values., Conclusions: The DNG/E2V COC has no short-term adverse effect on bone turnover markers. No significant change in BMD was observed after six months of use of that pill.

Preterm delivery (<37 weeks post-menstrual age) is associated with suboptimal bone mass. We hypothesized that tactile/kinesthetic stimulation (TKS), a form of infant massage that incorporates kinesthetic movement, would increase bone strength and markers of bone accretion in preterm infants. Preterm, AGA infants (29-32 weeks) were randomly assigned to TKS (N=20) or Control (N=20). Twice daily TKS was provided 6 days per week for 2 weeks. Control infants received the same care without TKS treatment. Treatment was masked to parents, health care providers, and study personnel. Baseline and week two measures were collected for tibial speed of sound (tSOS, m/sec), a surrogate for bone strength, by quantitative ultrasound (Sunlight8000) and urine markers of bone metabolism, pyridinium crosslinks and osteocalcin (U-MidOC and unOC). Infant characteristics at birth and study entry as well as energy/nutrient intake were similar between TKS and Control. TKS intervention attenuated the decrease in tSOS observed in Control infants (p<0.05). Urinary pyridinium crosslinks decreased over time in both TKS and CTL (p<0.005). TKS infants experienced greater increases in urinary osteocalcin (U-MidOC, p<0.001 and unOC, p<0.05). We conclude that TKS improves bone strength in premature infants by attenuating the decrease that normally follows preterm birth. Further, biomarkers of bone metabolism suggest a modification in bone turnover in TKS infants in favor of bone accretion. Taken together, we speculate that TKS improves bone mineralization., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Preterm (PT) infants are at risk of growth failure despite advanced early care and nutrition. In addition to poor weight gain, slow postnatal linear growth also is associated with adverse neurological outcome. Markers distinguishing infants at risk for impaired catch-up growth are needed. The aim of this longitudinal study was to determine the extent to which postnatal levels of circulating cartilage (serum pro-C-type natriuretic peptide [S-proCNP]) and urinary bone metabolic markers (urinary osteocalcin [MidOC] and two forms of C-terminal cross-linked telopeptide of type I collagen [U-α-CTX-I and U-β-CTX-I]) predict catch-up growth in infancy in 67 PT and 58 full-term (FT) infants. PT infants were significantly shorter than FT infants during the first 6 months of life, but no statistically significant difference was found at the corrected age of 14 months (M14). At the age of 3 months (M3), S-ProCNP and U-MidOC levels, but not U-α-CTX-I and U-β-CTX-I levels, correlated positively with prospective growth velocity from M3 to M14 (ρ = 0.460, p < 0.001 and ρ = 0.710, p < 0.001, respectively). In predicting slow linear growth (growth velocity at the lowest quartile), the area under the S-ProCNP ROC curve was 0.662 and that of U-MidOC 0.891. Thus, U-MidOC, and to lesser extent S-ProCNP at M3 are predictors of catch-up growth in infancy., (Copyright © 2012 American Society for Bone and Mineral Research.)

The authors present an assessment of bone structure condition in children with acute leukemia. The changes in the collagen molecule, amino acid composition of urine and proteins reparation processes were revealed. Calcium phosphate excretion in the patients urine were increased. The serum osteocalcin level and colony formation efficiency of bone marrow fibroblasts in acute leukemia patients are lower than in control group. In the initial period of the disease 32% of patients have disturbancies in their endocrine status. The bone structure violation is combined with unfavorable disease outcome. The effectiveness of the treatment and prevention steps in acute leukemia patients depends on the leukemic process stage.

Objectives: This study evaluated the influence of oestrogen deficiency and its therapies on bone tissue around osseointegrated implants., Methods: Implants were placed in 66 female rats tibiae. The animals were assigned into five groups: control (CTL), sham, ovariectomy (OVX), oestrogen (EST), and alendronate (ALE). While CTL was sacrificed 60 days after implant placement, other groups were subjected to ovariectomy or sham surgery according to group and euthanized after 90 days. Blood and urine samples were collected at sacrifice day for osteocalcin (OCN) and deoxypyridinoline (DPD) quantification. Densitometry of femur and lumbar vertebrae was performed in order to evaluate rats' skeletal impairment. Non-decalcified sections were referred to fluorescent and light microscopy for analyses of mineral apposition rate (MAR), eroded and osteoclastic surfaces, bone-to-implant contact (BIC), and bone area fraction occupancy (BAFO)., Results: Results from the OVX group showed significantly lower bone mineral density (BMD), BIC, BAFO, and MAR, while OCN, deoxipiridinoline, eroded surface and ostecoclastic surface were increased compared with the other groups of the study. ALE reduced OCN and DPD concentrations, MAR, osteoclastic and eroded surfaces, and no difference was in BIC and BAFO relative to SHAM. EST and CTL showed similar results to SHAM for measurements., Conclusions: Oestrogen deficiency exerted a negative influence on bone tissue around implants, while oestrogen replacement therapy and alendronate were effective against its effects. Although alendronate therapy maintained the quantity of bone around implants, studies evaluating bone turnover kinetics are warranted., (© 2010 John Wiley & Sons A/S.)

Background: Micro-structural changes associated with ultra high molecular weight polyethylene particle (UHMWPE) induced osteolysis, the most frequent cause of aseptic loosening, have been intensively investigated in the mammalian calvarian model by histomorphometry and micro-computed tomography. However, little is known regarding the serological changes that occur during this process., Methods: Serological parameters for bone metabolism [calcium, phosphate, osteocalcin (OCN), deoxypyridinoline (DPD)/creatinine, alkaline phosphatase, osteoprotegerin and receptor activator of nuclear factor-κB] were analyzed in this animal model for particle induced osteolysis. Ten C57BL/6 mice were divided at random into sham operated and UHM-WPE implanted groups. Blood and urine samples were collected prior to and at 14 days after surgery., Results: Implantation of UHMWPE lead to a significant decrease in bone volume (p=0.027). Both groups (sham/UHMWPE) showed a significant increase in calcium (p=0.004/p=0.027) and phosphate (p=0.001/p=0.001), without correlation to particle implantation. Significantly higher concentrations of DPD/creatinine (p=0.034) and OCN (p=0.022) were found after implantation of UHM-WPE. In addition, parameters could not be correlated to particle induced osteolysis., Conclusions: DPD can be regarded as a valuable parameter for detecting UHMWPE induced osteolysis in the calvarian model. Further studies of serum parameters should focus on the clinical relevance in aseptic prosthetic loosening.

N-methyl-D-aspartate (NMDA) receptors (NMDAR) are tetrameric amino acid receptors that act as membrane calcium channels. The presence of the receptor has been detected in the principal organs responsible for calcium homeostasis (kidney, bone, and parathyroid gland), pointing to a possible role in mineral metabolism. The aim of this study was to test the effect of NMDAR activation in the kidney and on 1,25(OH)₂D₃ synthesis. We determined the presence of NMDAR subunits in HK-2 (human kidney cells) cells and proved its functionality. NMDA treatment for 4 days induced a decrease in 1α-hydroxylase levels and 1,25(OH)₂D₃ synthesis through the activation of the MAPK/ERK pathway in HK-2 cells. In vivo administration of NMDA for 4 days also caused a decrease in blood 1,25(OH)₂D₃ levels in healthy animals and an increase in blood PTH levels. This increase in PTH induced a decrease in the urinary excretion of calcium and an increase in urinary excretion of phosphorous and sodium as well as in diuresis. Bone turnover markers also increased. Animals with 5/6 nephrectomy showed low levels of renal 1α-hydroxylase as well as high levels of renal glutamate compared with healthy animals. In conclusion, NMDAR activation in the kidney causes a decrease in 1,25(OH)₂D₃ synthesis, which induces an increase on PTH synthesis and release. In animals with chronic kidney disease, high renal levels of glutamate could be involved in the downregulation of 1α-hydroxylase expression.

Bone mineral density (BMD) is affected in young adults with multiple sclerosis (MS), which leads to disabling disease. We aimed to show changes that were independent of immobilization by measuring BMD and laboratory markers of bone metabolism in mobile MS patients. We compared a total of 52 premenopausal female patients with relapsing-remitting multiple sclerosis (RRMS) to 41 women of similar age who had no risk factors for osteoporosis. The lumbar and femur BMD were measured using the dual energy X-ray absorptiometry (DXA) method. The urine concentration of serum 25-hydroxycholecalciferol (25-OH vit D(3)), and pyridinoline and deoxypyridinoline were also measured. The concentration of serum osteocalcin was measured to determine the speed of bone metabolism. The mean age of patients (+/- standard deviation [SD]) was 36.1+/-7.4. The average Expanded Disability Status Scale (EDSS) score was 2.2+/-1.8. The concentration of 25-OH vit D(3) and osteocalcin was lower, whereas the concentration of parathyroid hormone (PTH), alkaline phosphatase (ALP), pyridinoline and deoxypyridinoline was higher in the patient group. In the patient group, lumbar 2-4 BMD, T score and Z score and femur neck and trochantor BMD, T score and Z score were significantly lower than in the control group. There was a significant negative relationship between: the disease period and L 2-4 BMD, T score and Z scores; and the femoral neck BMD, T score and Z scores. There was a significant relationship between the total Functional Independence Measure score and the femoral neck, femoral trochanter BMD, T score, and Z score. There was a significant negative relationship between the average EDSS, L 2-4 and all the DXA measurements obtained from the femur. There was a significant relationship between the 25-OH vit D(3) concentration and L 2-4 T score and Z score from the DXA measurements obtained from the femur. There were no significant relationships between osteocalcin, pyridinoline, deoxypyridinoline levels and the BMD measurements. Therefore, the duration of the disease and decrease in functional capacity are the main factors that affect BMD in MS. Apart from the decrease in functional capacity, 25-OH vit D(3) deficiency and secondary PTH increase contribute to the BDM changes observed in MS., (Copyright 2010 Elsevier Ltd. All rights reserved.)

The purpose of this study was to determine the effects of a 3-month walking exercise program with ankle weights on fall-related fitness, bone metabolism, and fall-related psychological factors. Fall-related fitness was determined from strength, balance, agility, aerobic endurance, muscle mass, and fat mass measures. Bone metabolism was measured using bone density, hormones, and biochemical markers. Fall-related psychological factors included fear of falling and falls efficacy. A 2 × 2 factorial with repeated measures design was used. All subjects were community-dwelling elderly women who volunteered to participate, and randomly were assigned to either an exercise group (n = 11) or a control group (n = 10). Results revealed significant changes in upper body strength, leg strength, aerobic endurance, and body composition. Additionally, hormones and biochemical markers changed significantly over time. Trunk fat and fear of falling changed differently among the two groups. In conclusion, this study suggests that a 3-month walking exercise program with ankle weights may have positive effects on fall-related fitness, bone metabolism, and fall-related psychological factors.

Objective: To determine the effects of calcium supplementation on bone physiology in corticosteroid-free children with juvenile rheumatoid arthritis (JRA) by measuring serum and urinary bone-related hormones, minerals, and markers of bone formation and resorption., Methods: In this double-blind trial, patients were randomized to receive daily oral supplementation with 1,000 mg of calcium and 400 IU of vitamin D or with placebo and 400 IU of vitamin D for 24 months. The effect of calcium supplementation on bone physiology was determined periodically using markers of bone turnover., Results: One hundred ninety-eight patients met the inclusion criteria and were followed up in the study. At baseline, there were no differences in markers of bone turnover between the groups. Patients with < or = 4 joints with active disease had higher serum levels of calcium and parathyroid hormone (PTH). Calcium-treated patients with < or =4 joints with active disease had lower levels of osteocalcin (OC). At followup, levels of 1,25-dihydroxyvitamin D3, PTH, OC, and urine phosphorus were lower in the group receiving calcium supplementation. Hypercalciuria, as determined by the urinary calcium-to-creatinine ratio, was not noted in 24-hour urine studies., Conclusion: Levels of markers of bone physiology were significantly decreased in children with JRA receiving calcium supplementation. The physiologic changes were noted as early as 12 months into calcium supplementation. The hypercalciuria noted on spot testing of the urinary calcium-to-creatinine ratio was not demonstrated on further evaluation, nor did it lead to renal pathology. These findings suggest that the calcium supplementation met physiologic needs and caused an increased calcium loss in urine.

The purpose of the treatment of osteoporosis is to reduce fracture risk and maintain/improve quality of life (QOL). The criteria for initiating pharmacotherapy to prevent fragility fractures should be provided separately from the criteria for diagnosis of osteoporosis. In Japan, low bone mineral density (BMD), prevalent fracture, and age are established as fracture risk factors from available data. A meta-analysis conducted by the WHO assured that excessive drinking (2 units a day or more), current smoking, and a family history of hip fracture are fracture risk factors. Moreover, in WHO technical report 921, high levels of CTX, a bone resorption marker as well as uncarboxylated osteocalcin were cited as risk factors of hip fracture, which can be measured in medical practice in Japan. Pharmacotherapy should be initiated with the consideration of the above risk factors. Recent large scale of randomized control trial(RCT), followed by meta-analysis demonstrated that bisphosphonates such as alendronate and risedronate as well as raloxifene (selective estrogen receptor modulator) are top grade of drugs which prevent fragility fracture in osteoporotic patients. Now, it is possible to perform evidence-based medicine in daily medical practice. As for secondary osteoporosis, along with treatment of underlying diseases, treatment aimed at preventing bone loss is necessary in many cases. Accumulating evidence is available about increased fracture threshold in glucocorticoid- and diabetes mellitus-induced osteoporosis. Therefore, early treatment should be appropriate in these cases. In osteoporotic patients, atherosclerotic vascular calcification as well as abnormal lipid metabolism often coexists. Multiple vertebral fractures followed by kyphosis often causes functional disorders of the digestive and respiratory systems.

Objective: Serum osteocalcin (S-OC) is widely used as an index of bone formation. However, there is evidence that some urinary fragments of OC reflect resorption and might be useful in monitoring antiresorptive therapy. Here, we report 6-month changes in urinary midfragments of osteocalcin (U-MidOC) and other bone turnover markers in response to risedronate treatment., Material and Methods: The study group comprised 19 patients with postmenopausal osteoporosis, aged 49-66 years, and receiving risedronate therapy. Fifty-four premenopausal women served as controls. Osteoporosis was diagnosed by lumbal bone mineral density (BMD). Urinary osteocalcin was measured by the U-MidOC assay for midfragments. Bone formation was assessed by S-PINP and S-OC, and resorption by S-CTx-I., Results: At baseline, U-MidOC was significantly correlated only with S-OC. After the 1st month of therapy, a similar decrease was observed in the values of U-MidOC and S-CTx-I, but in formation markers S-P1NP and S-OC only after three months. The rapid decrease in U-MidOC, analogous to S-CTX-I, and the different kinetics for urinary and serum OC suggest that urinary OC midfragments are more associated with resorption than S-OC. An association was also observed between the 1-month change in U-MidOC and 12-month gain in lumbar BMD. The response in U-MidOC after only the 1st month of therapy makes it a potential marker for monitoring the effect of risedronate, presumably reflecting different aspects of bone resorption than S-CTx-I does.

Objective: To evaluate the relationships among cartilage and subchondral bone before and after the onset of cartilage degeneration in the Hartley guinea pig model of spontaneous osteoarthritis (OA) as compared with those in Weiser-Maple guinea pigs, which do not develop OA., Methods: Mice from each strain were used at ages 2, 3, 5, and 8 months (n = 7 at each time point). The region observed was the medial tibial plateau. Cartilage degeneration was evaluated histologically. Subchondral bone structure was evaluated based on subchondral bone plate thickness and subchondral cancellous bone trabecular parameters calculated from the microfocal computed tomography 3-dimensional reconstruction image. The bone mineral density (BMD) of the subchondral cancellous bone as well as levels of urinary N-telopeptide of type I collagen (NTX) and serum osteocalcin (OC) were measured., Results: In Hartley guinea pigs, the number of chondrocytes in the surface layer started to decrease at 3 months. At 8 months, fibrillation expanded to the radial zone. In Weiser-Maple guinea pigs, no cartilage degeneration was noted even at 8 months. Subchondral bone plate thickness was significantly lower in Hartley guinea pigs than in Weiser-Maple guinea pigs at 2 months. The subchondral bone had a rod-like and convex structure at 2 months in Hartley guinea pigs. BMD was significantly lower in Hartley guinea pigs than in Weiser-Maple guinea pigs at 2 months. The serum OC level was significantly higher in Hartley guinea pigs than in Weiser-Maple guinea pigs at 2 months and 3 months, whereas the urinary NTX level was significantly lower in Hartley guinea pigs at 3 months., Conclusion: Subchondral bone is fragile, and bone formation may be promoted in subchondral bone before the onset of cartilage degeneration in Hartley guinea pigs. Subchondral bone may be involved in the development of OA.

Background: Phase III study comparing the effect of oral ibandronate and intravenous zoledronic acid on bone markers., Patients and Methods: Breast cancer patients with bone metastases received ibandronate 50 mg/day (n = 137) or zoledronic acid 4 mg every 4 weeks (n = 138) for 12 weeks. The primary end point was mean percentage change in serum levels of cross-linked C-terminal telopeptide of type I collagen (S-CTX) at week 12. Urinary CTX (U-CTX), bone alkaline phosphatase (ALP), amino-terminal procollagen propeptide of type I collagen (PINP) and osteocalcin (OC) were also measured and bone pain and safety assessed., Results: Both bisphosphonates significantly reduced S-CTX (mean ibandronate 76% +/- 29 (SD) versus mean zoledronic acid 73% +/- 47; P < 0.001 for both versus baseline) and U-CTX (ibandronate 78% +/- 50 versus zoledronic acid 86% +/- 17; P < 0.001). The difference in S-CTX between treatments was 0.6% (confidence interval -1.7% to 3.0%), which was within the prespecified noninferiority margin. Bone ALP, PINP and OC decreased by 26%-47% compared with baseline with both bisphosphonates. Compared with zoledronic acid, ibandronate patients reported fewer adverse events overall (65.0% versus 75.9%), and on days 1-3 (8.0% versus 47.5%), including less pyrexia (overall incidence 0% versus 16.8%) and bone pain (5.8% versus 12.4%)., Conclusions: Oral ibandronate was well tolerated and statistically noninferior to zoledronic acid for percentage change in the bone resorption marker, S-CTX.

Introduction: The purpose of this 3-way crossover study was to identify the effective dose of soy protein isolate enriched with isoflavones for suppressing bone resorption in postmenopausal women using a novel, rapid assessment of antibone resorbing treatments., Methods: Thirteen postmenopausal women (>or=6 yr since menopause) were predosed with 41Ca iv. After a 200-d baseline period, subjects were given 43 g soy protein/d that contained 0, 97.5, or 135.5 mg total isoflavones in randomized order. The soy protein isolate powder was incorporated into baked products and beverages. Each 50-d intervention phase was preceded by a 50-d pretreatment phase for comparison. Serum isoflavone levels and biochemical markers were measured at the end of each phase. Twenty-four-hour urine samples were collected approximately every 10 d during each phase for 41Ca/Ca analysis by accelerator mass spectrometry., Results: Serum isoflavone levels reflected the amount of isoflavones consumed in a dose-dependent manner. None of the isoflavone levels had a significant effect on biochemical markers of bone turnover, urinary cross-linked N teleopeptides of type I collagen and serum osteocalcin, or bone turnover as assessed by urinary 41Ca/Ca ratios., Conclusions: Soy protein with isoflavone doses of up to 135.5 mg/d did not suppress bone resorption in postmenopausal women. This is the first efficacy trial using the novel technique of urinary 41Ca excretion from prelabeled bone.

The ovariectomized (OVX) rat, as an established animal model of human osteoporosis, was adopted in the present experiment to study the protective effects of sodium daidzein sulfonate (SDS) on trabecular bone. Six-month-old Sprague-Dawley rats were sham-operated or ovariectomized. Five days later, the OVX rats were randomly assigned to one of three experimental groups and treated for 90 days with vehicle, 17beta-estradiol (E(2)) or SDS. Compared with OVX rats, SDS administration (15 mg/kg) prevented OVX-induced decrease in lumbar vertebral and femoral bone mineral density (BMD), and significantly increased bone mechanical strength parameters, including ultimate stress and elastic modulus. In the OVX group, the structure of trabecular plate in the femoral head was absorbed and became progressively thinner or was removed completely, accompanied by enlargement of marrow cavities and amalgamation of two or more marrow cavities. Administration of SDS and E(2 )prevented the change of trabecular bone microarchitecture induced by OVX, increasing the trabecular bone area and trabecular thickness, while decreasing the trabecular separation. These results indicate that SDS administration prevents OVX-induced decrease in BMD and bone mechanical strength, and has a moderate protective effect on the microarchitecture of trabecular bone in aged Sprague-Dawley rats., ((c) 2007 S. Karger AG, Basel.)

Objective: To evaluate prospectively the efficacy of bisphosphonate treatment in infants with severe forms of osteogenesis imperfecta (OI)., Study Design: Of 10 children (6 females) with OI type III, 5 (group A) started treatment (2 mg/kg neridronate administered intravenously for 2 consecutive days, every 3 months) just after diagnosis at birth and 5 (group B) after 6 months. Ten untreated children, matched for sex, age, and clinical severity of OI, constituted a historical control group (group C). We measured weight, length, and number of fractures every 3 months and serum and urinary levels of calcium, phosphorus, creatinine, serum alkaline phosphatase, 25-hydroxyvitamin D, insulin-like growth factor I, parathyroid hormone, and osteocalcin, urinary type I collagen N-terminal telopeptide, and lateral radiography of vertebral column every 6 months., Results: Group A had better growth and a lower incidence of fractures than groups B and C in the first 6 months of treatment. In the second 6 months, both groups A and B had lower fracture rates than group C. After 12 months of therapy, osteocalcin and insulin-like growth factor I levels significantly increased only in group A. The urinary Ca/Cr ratio and N-terminal telopeptide/Cr ratio significantly declined only in treated patients. Vertebral body area and the structure of vertebral bodies improved in all treated patients, but especially in group A., Conclusions: Cyclical neridronate treatment, started just after diagnosis at birth, had positive effects on growth and fracture rate.

Objective: To investigate the association between biochemical markers of bone, cartilage, and synovial turnover with the presence and severity of knee osteoarthritis (OA) in men., Methods: 176 men aged 59-70 years from the MRC Hertfordshire Cohort were studied. Weightbearing anteroposterior and lateral semiflexed radiographs were taken of both knees. A lifestyle questionnaire including basic demographic details and a questionnaire detailing knee pain was completed. This random sample was stratified based on the Kellgren and Lawrence (K&L) score, and the following biochemical markers were analysed: serum osteocalcin, serum C-terminal crosslinked telopeptide of type I collagen (CTX-I), urinary C-terminal crosslinked telopeptide of type II collagen (CTX-II), and urinary glucosyl-galactosyl-pyridinoline (Glc-Gal-Pyd)., Results: Age, body mass index (BMI), social class, smoking, and alcohol consumption were similar across K&L grades. Only one subject had a grade 4 K&L score, and was amalgamated with grade 3 subjects. A strong significant association was found between the presence of knee OA and urinary CTX-II and urinary Glc-Gal-Pyd (p=0.0001 and p=0.009), which persisted after adjustment for age and BMI. A significant positive association was also found between urinary CTX-II and urinary Glc-Gal-Pyd and the severity of K&L grade, joint space narrowing, and osteophytes scores, which persisted after adjustment for age and BMI. No associations between the presence and severity of knee OA were found for serum CTX-I or serum osteocalcin., Conclusions: Urinary CTX-II and Glc-Gal-Pyd, but not systemic markers of bone turnover, are strongly associated with disease severity and the presence of OA at the tibiofemoral and patellofemoral joints in men.

The effects of acupuncture on bone biomechanical properties and histomorphometry in ovariectomized (OVX) rats were studied. Twenty-four 8-week-old female Sprague-Dawley rats were randomly assigned to three groups: sham, model and acupuncture. Rats in the model and acupuncture groups were ovariectomized, while those in the sham group underwent a sham operation. All rats were anesthetized and fastened for 15 minutes, and for the acupuncture group, needling on Pishu (BL20) and Shenshu (BL23) was performed. Blood and urine were collected to measure serum osteocalcin (OC) and urinary calcium, phosphorus or deoxypyridinoline (Dpd). After 16 weeks of treatment, all the rats were killed and their tibiae and femora were removed. The tibiae were used for analyses of bone histomorphometry and the femora for a three-point bending test. Acupuncture gave significant protection against ovariectomy-caused decline on femoral strength in the mechanical test, increased the trabecular bone volume and thickness, lowered the trabecular separation of tibiae and restricted the excretion of phosphorus and Dpd, while promoting the concentrations of serum osteocalcin as compared with model rats. These results seemed to indicate that acupuncture on the points of Pishu (BL20) and Shenshu (BL23) not only promoted the bone formation but also suppressed the bone resorption induced by OVX in osteoporotic rats, which suggests that it would be a potentially useful and convenient method in preventing osteoporosis.

Unlabelled: The bone phenotype of mice overexpressing MIF was studied. These mice showed decreased trabecular bone, increased bone formation rate, and increased MMP-3, -9, and -13 mRNA expression in the femora and tibias. This model provides evidence of the role played by MIF in bone remodeling and balance in vivo., Introduction: The role of macrophage migration inhibitory factor (MIF) in in vivo bone remodeling remains unelucidated. We describe disordered bone metabolism in transgenic mice overexpressing MIF., Materials and Methods: For in vivo study, muCT, bone histomorphometry, blood and urine biochemical data, and gene expression of MIF transgenic (MIF Tg) mice and littermate wildtype (WT) mice were examined. For in vitro study, osteoclastogenesis in the co-culture of bone marrow cells and osteoblasts from MIF Tg and WT were assessed., Results: muCT analyses revealed a significant reduction in the trabecular bone of distal femur in MIF Tg at 8-12 weeks of age. Histomorphometric analysis revealed increase in several measures of bone formation. Osteoclastogenesis was not influenced by the origin of bone marrow cells or osteoblasts. Urine level of deoxypyridinoline/creatinine and the mRNA levels of matrix metalloproteinase (MMP) -3, -9, and -13 in femurs were elevated in MIF Tg., Conclusions: Overexpression of MIF causes high-turnover osteoporosis in mice. The increased expression of MMPs in bone was suggested, at least in part, as one cause of this phenotype, because MMPs plays important roles for bone resorption without affecting the formation of osteoclasts. This model provides evidence of the role played by MIF in bone remodeling and balance.

Aim: To assess the influence of metabolic disorders on densitometric parameters in patients with anorexia nervosa., Material and Methods: Thirty patients with diagnosis of anorexia nervosa and twenty six healthy females from control group participated in the study. Serum calcium, phosphorus, estradiol, cortisol, osteocalcin and C-terminal telopeptide of collagen type I concentrations were estimated. Urine sample was analysed for 24 hrs excretion of calcium and phosphorus. Lumbar bone mineral density and Z-score were assessed by DEXA., Results: Statistical analysis showed the presence of positive correlation between densitometric parameters and serum concentrations of estradiol and phosphorus and negative correlation with serum concentration of cortisol. The duration of anorexia nervosa and secondary amenorrhea correlated negatively with densitometric parameters. There was no correlation between bone turnover markers and densitometric parameters., Conclusions: Current data are in agreement with hypothesis of multifactorial ethiopathogenesis of osteoporosis in anorexia nervosa.

The purpose of this study is to evaluate urinary biomarkers of bone formation and resorption as predictive factors for oral implant failure, and to contribute to the knowledge of factors related to oral implant failure. A total of 93 patients between 18 and 85 years old, with an indication of oral implant, were eligible in this 2-year prospective, open, and nonrandomized study. Patients who had bone graft before implantation or presented with prosthetic difficulties (implant-to-crown ratio < 1, and/or unfavorable intermaxillary space) were excluded. All patients received either Frialit-2 (Friadent, Mannheim, Germany), cylinder, or screwed implants or IMZ Twin Plus (Friadent), cylinder implants, with FRIOS (Friadent) titanium coating. Serum osteocalcin, and urinary pyridinoline and deoxypyridinoline were measured, together with bone density at implant location. The primary endpoint (implant failure) was the implant removal (radiographic evidence of peri-implant bone loss and/or pockets). Factors related to implant failure were analyzed using multilevel logistic regression models to consider within-patient effects. Of the 93 patients included, 61% were female, and 16% were current smokers. A total of 266 oral implants were placed and analyzed, with a mean number of 3.1 implants by patient. Eleven and 15% of bone locations scored at D1 and D4, respectively, for the Misch bone density scoring. The majority of implants (72%) were placed more than 3 months after tooth extraction, using a Frialit-2 system in 73% of cases. The mean of osteocalcin was 17.3 (+/-9.4) ng/L; those of pyridinoline and deoxypyridinoline were 33.2 (+/-15.8) and 10.2 (+/-11.9) mmol per creatinine mmol, respectively. At one-year, 95.5% (95% confidence interval 92.5-97.5) of implants have not been removed. One year later, no further implant failed. In both univariate and multivariate analysis, osteocalcin, pyridinoline, and deoxypyridinoline were not significant predictive factors of oral implant failure. In multilevel logistic regression analysis, only tobacco consumption and single-tooth replacement or removable prosthesis were independent and significant predictive factors of oral implant failure. Serum osteocalcin, and urinary pyridinoline and deoxypyridinoline were not predictive of oral implant failure in this study. These results suggest that oral implants are more likely to fail for posterior single-tooth replacements and removable prostheses rather than for complete edentulous fixed bridgeworks or overdentures. Tobacco smoking has been identified as a major risk factor of oral implant failure.

Background: Osteocalcin (OC) is produced by osteoblasts during bone formation, and circulating OC has been used in clinical investigations as a marker of bone metabolism. OC is excreted into urine by glomerular filtration and can be found in urine as midmolecule fragments., Methods: We developed and evaluated three immunoassays (U-MidOC, U-LongOC, and U-TotalOC) for the detection of various molecular forms of urine OC (U-OC). We evaluated the association of U-OC with other markers of bone turnover and with bone mass in 1044 elderly women and studied seasonal and circadian variation of U-OC., Results: U-OC correlated with other bone turnover markers [Spearman correlation (r), 0.30-0.57; P <0.0001], demonstrating the association between U-OC and skeletal metabolism. There was also a significant association between bone metabolism assessed by U-OC quartiles and bone mass assessed by total body bone mineral content (P <0.0001). The seasonal effects appeared to be rather small, but we observed a significant circadian rhythm similar to the one reported for serum OC with high values in the morning and low values in the afternoon., Conclusions: The three immunoassays had unique specificities toward different naturally occurring U-OC fragments. U-OC concentrations measured with any of these assays correlated with bone turnover rates assessed by conventional serum markers of bone metabolism. The measurement of OC in urine samples could be used as an index of bone turnover in monitoring bone metabolism.

To examine the short- and long-term bone metabolic effects of fracture assessed by biochemical markers, we utilized a clinical fracture model-proximal tibial osteotomy-and prospectively followed 14 patients. This model of an induced fracture of a major bone gives the advantage of assessing baseline levels prior to fracture. Follow-up occurred at 6-9 weeks, 4-7 months, 9-13 months, and 14-17 months after fracture. Serum was assayed for type 1 procollagen peptide (PICP), total alkaline phosphatase (ALP), and carboxy-terminal-telopeptide of type I collagen (ICTP), while deoxypyridinoline (Dpyr) was measured in urine. Serum osteocalcin (OC) was measured using two recently developed two-site immunofluorometric assays, which both measure full-length and fragmented forms of OC (OCtot), with one of the assays specifically detecting only the carboxylated form of OC (OCcxy). In addition, OC was measured in urine using the same assays as those used for serum. Serum OCtot increased to a peak at 4-7 months after fracture (P < 0.001) and a similar increase was seen for OCcxy (P < 0.05) and ALP (P < 0.01). Bone formation had returned to baseline after a year. Dpyr increased significantly, with a doubling at 6 weeks, while serum (S)-ICTP increased by 73% (P < 0.01 and P < 0.001). Urine OC increased to a maximum of 84% at 6 weeks. The initial percentage increase of bone resorption was greater than that of bone formation. We conclude that: (1) bone turnover as measured by biochemical markers is altered soon after fracture, (2) the major changes occur within 6 weeks to 6 months, but may persist for up to a year. (3) The initial increase in bone resorption exceeds the increase in bone formation, which may contribute to the enhanced bone loss after fracture. (4) The two novel urine OC assays show a similar pattern of change as established marks of bone resorption, which may indicate that they measure bone resorption. (5) Fracture-induced effects on bone turnover are significant and, thus, are potential confounders in the assessment of osteoporosis.

Production of bone resorption mediators and bone resorption activity were compared among osteolytic metastatic cancers, normal bone tissues, and soft tissue metastatic cancers to search for the possible factors leading to cancer-induced bone resorption. Twenty-five patients with untreated osteolytic metastatic breast or non-small cell lung cancers consisted of the study group. Normal bone tissues obtained from the same patient were used as internal controls; and tumor tissues from patients with soft tissue metastasis were used as external controls. Serum and urinary bone turnover markers were measured. Tissues harvested during surgery were subjected to tissue culture. The levels of prostaglandin E2 (PGE2), tumor necrosis factor-alpha (TNF-alpha), and interleukin-6 (IL-6) in the supernatant after 72 h of culture were measured. Bone resorption activity was measured by calcium release from cultured calvarias, and bone volume as well as osteoclast number in bone sections. Patients with osteolytic metastatic cancers showed significantly decreased serum osteocalcin, increased serum alkaline phosphatase, and urinary deoxypyridinoline levels. Osteolytic metastatic cancers produced significantly more PGE2 than both controls. Conditioned medium from osteolytic metastatic tumors showed significantly enhanced bone resorption activity, and indomethacin significantly reduced this activity. Levels of PGE2, and bone resorption activity increased in osteolytic tumor tissues than soft tissue metastatic tissues in the same patient indicated that the same tumor cells might respond differently to different microenvironments. Our observation showed that PGE2 was produced by osteolytic metastatic cancers and stimulated bone resorption in mice calvarias. PGE2 inhibitor may be applicable in reducing bone resorption by osteolytic metastatic cancers.

The evaluation of bone disease in multiple myeloma (MM) by conventional radiology has low reproducibility. In the last decade, several serum and urine biochemical parameters, for evaluation of bone turnover, have become available. The present study was designed to explore the value of six bone remodelation markers. It was studied in a series of 176 newly diagnosed patients with monoclonal gammopathies (107 MM and 69 monoclonal gammopathies of unknown significance (MGUS)). As control groups we used 25 patients with benign osteoporosis (BO) and 32 healthy individuals (HI). The bone markers analyzed included: bone resorption markers (BRM) (total pyridinoline, total deoxypyridinoline, free deoxypyridinoline and C-terminal telopeptide of collagen I) and bone formation markers (BFM) (bone alkaline phosphatase (bAP) and osteocalcin (OC)). Serum or urinary levels of BRM were significantly higher in MM patients than in MGUS patients, BO patients or HI (P < 0.001, respectively). BRM were higher in MM patients with lytic lesions. However, only C-terminal telopeptide discriminated MM patients without bone lesions from MGUS patients. BFM did not show significant differences in the aforementioned comparisons, although a trend toward higher values of OC and lower values of bAP in patients with early bone affectation was observed. Ratios BRM/BFM that contained bAP exhibited differences that were most significant between the MM group and other entities, as well as between the different MM subgroups. In fact, the ratios BRM/bAP provided discrimination between the MM subgroup without lyses and MGUS group (P < 0.01). BRM and BFM, especially the ratios, are useful in the evaluation of bone lesions in patients with monoclonal gammopathies.

Introduction: Osteocalcin (OC) is a small bone matrix protein exclusively found in mineralized tissue. OC measured in serum or plasma provides an index of bone formation. In the present study a sensitive inhibition ELISA was established that could quantify fragments derived from the OC Mid-region in human urine., Methods: The ELISA was based on a monoclonal antibody directed against residues 21-29 of human OC (Mid-OC Urine ELISA). OC fragments were isolated from human urine by immunoaffinity chromatography. OC fragments were purified further by reversed phase high performance chromatography for characterization by N-terminal sequencing and mass-spectrometry. OC fragments were assayed in bone cell culture supernatants and in serum and urine from patients undergoing anti-resorptive bisphosphonate therapy using the Mid-OC urine ELISA., Results and Conclusion: It was demonstrated that the release of OC fragments was highly correlated with osteoclast-mediated pit formation (r2= 0.89) and with an established marker of bone resorption (CTX; r2=0.91). Mid-OC values were decreased markedly after 3 and 10 days of anti-resorptive bisphosphonate treatment further indicating that the marker reflects bone resorption. The molecular characterization revealed that most of these molecules were less than 15 amino acids in length and many contained modified aspartyl residues (D-aspartyl and isoaspartyl) characteristic of aged proteins. The presence of such modifications shows that these molecules have resided in the bone matrix for an extended period and thus they cannot be derived directly from bone formation. In conclusion, these findings demonstrate that OC-fragments are released during osteoclastic bone resorption and that the quantification of specific age-modified OC fragments can provide an index of bone resorption.

Background and Aims: Osteoporosis may occur in 25-30% of patients with Crohn's disease. Its pathogenesis is not completely understood. Both systemic inflammation in acute disease and treatment with systemic glucocorticoids have been implicated. The aim of the present study was to investigate changes in bone density and biochemical markers of bone metabolism before and during a 3-month period of high-dose glucocorticoid treatment for acute flare-up of Crohn's disease., Methods: Twenty-five patients with active Crohn's disease requiring systemic glucocorticoid treatment (prednisolone, 60 mg/day) were investigated. Lumbar spine and femoral neck bone mineral densitometry was performed at baseline and again after 3 months. Clinical examinations including evaluation of the Crohn's disease activity index and measurement of the biochemical markers osteocalcin, deoxypyridinoline, osteoprotegerin and the soluble receptor activator of NF-kappaB ligand were performed prior to, and at 1, 2 and 12 weeks following steroid administration. RESULTS Median lumbar bone mineral density decreased significantly during the observation period by 1.04% from -0.84 (t score; range, -2.8 to +0.57) to -0.95 (range, -3.1 to +0.40; P = 0.022), while bone density of the total femur decreased by 2.9% from -0.83 (range, -2.61 to +1.86) to -0.90 (range, -2.65 to +0.19; P = 0.01). Serum levels of osteocalcin, a bone formation marker, and osteoprotegerin, an anti-resorptive cytokine produced by osteoblasts, decreased after the first 2 weeks of treatment and reached baseline levels after 3 months. No significant change was found for the bone resorption marker deoxypyridinoline, while soluble receptor activator of NF-kappaB ligand, a cytokine promoting bone resorption, tended to increase during steroid treatment., Conclusion: A decrease in bone mineral density in patients with Crohn's disease appears to result, at least in part, from a short-term effect of systemic glucocorticoid. Modulation of osteoclastogenesis by the receptor activator of NF-kappaB ligand/osteoprotegerin cytokine system and decreased osteoblastic function may be the underlying molecular basis.

In this study, we report the isolation and characterization of osteocalcin in human urine using mass spectrometry and N-terminal sequencing. Multiple proteolytic forms of osteocalcin were found, which consisted of 16-27 residues from the middle region of the molecule. Several fragments had residue Gly7 at the N-terminus and the most predominant was fragment 7-31. Additional fragments starting from residue Asp14 were detected in the samples of children and young adults. Immunochemical detection of urine osteocalcin fragments had a statistically significant negative correlation to bone mineral density in evaluation of urine samples from 75-year-old women. Thus, the measurement of osteocalcin fragments in urine may have potential applications in diagnostics related to disorders of bone metabolism.

Bisphosphonates are now in the vanguard of osteoporosis treatment. Frequently, gastro-oesophageal symptoms are associated with these drugs. The objective of this study was to compare side effects and bone turnover markers in postmenopausal women who had received alendronate daily or weekly in tablets with or without enteric coating. We conducted a randomised, double-blind, 3-month trial. The trial involved 75 volunteers, aged 45-58 with moderate to severe osteopenia (T-score lower than -2 SD) assessed by quantitative ultrasound. Women were assigned randomly to receive: (a) alendronate 10mg/day: (b) alendronate 70 mg once a week: or (c) enteric alendronate 70 mg per week. We recorded side effects, C-telopeptide, osteocalcin and urine hydroxyproline at the start of the study and at 3 months. After 3 months, pyrosis (heartburn) was noted by seven women in group A (28%), three in group B (12%) and two in group C (8%); nausea: by one woman in group B; and headache by one patient in each group. C-telopeptide (A: 40.7%; B: 34.1% and C: 38.5%); hydroxyproline (A: 31.1%;B: 25.3% and C: 31.5%) and osteocalcin (A: 27.0%; B: 25.4% and C: 25.1%) decreased similarly in the three groups. Weekly intake of alendronate, whether conventional or enteric-coated; is associated with less heartburn and nausea. Enteric alendronate has a similar action to the conventional tablets on biochemical markers.

Background: The connection between osteoarthritis (OA) and osteoporosis (OP) has attracted considerable attention but reports about bone mass density (BMD) in OA are often contradictory. Some data indicate that BMD is higher in OA patients than in healthy subjects, whereas other studies showed no differences. It has been observed that mud pack treatment (MPT) induces a decrease in cytokines with bone-resorbing effects. The aim of this study is to evaluate the response of bone and connective tissue to physical exercise and thermal treatment., Methods: Forty osteoarthrosic patients were divided in group A (physical exercise and MPT), and group B (physical exercise alone). Blood and urine samples were collected before and after the treatments to assay blood metabolic markers and urinary hydroxyproline., Results: In group A, some parameters show statistically significant differences before and after mud pack treatment (MPT). In group B, all parameters present no statistical significant changes before and after the physical exercise program., Conclusions: Few studies established the importance of exercise to maintain normal cartilage and bone metabolism. In group A of the present study, an influence on all the parameters of bone metabolism is evident. It is possible that physical exercise only if combined with MPT stimulates physiologic bone metabolism and favors skeletal health., (Copyright 2002 Elsevier Science B.V.)

We isolated and characterized a peptide fragment corresponding to amino acid sequence 14-28 of human osteocalcin in urine from Paget's disease, and developed a polyclonal antibody reactive to this peptide in urine. We used this antibody to measure urinary fragments of osteocalcin and compared to efficacy of the urinary osteocalcin assay with a serum osteocalcin (sOC) assay (ELISA-Osteo, Cis-Bio International) to monitor the short-term changes in bone turnover in response to alendronate treatment. The synthetic peptide-based urinary osteocalcin (uOC) radioimmunoassay (RIA) showed an analytical sensitivity of 6.25 ng/mL, standard curve range of 3.12-400 ng/mL, and mean intra- (n = 20) and interassay (n = 30) coefficient of variation (CV) of <15%. Urine osteocalcin concentrations in postmenopausal osteoporotic patients were approximately 90% higher than in normal premenopausal controls. Series of 24 h urine and matched serum samples were collected at baseline, 30 days, and 90 days after treatment of postmenopausal osteoporotic patients with daily dose of 10 mg alendronate. We measured urinary osteocalcin (uOc) levels and urinary N-telopeptide (uNTx, Ostex) in urine samples and serum N-telopeptide (sNTx), C-telopeptide (sCTx, Osteometer), serum osteocalcin (sOC) as well as bone-specific alkaline phosphatase (sALP) (Alkphose-B, Metra Biosystems) in serum samples. The percent change data obtained between baseline and 30 days (n = 18) posttreatment suggested a rapid decline in uOC concentration (-27%, p < 0.01) in response to alendronate treatment, as compared with a marginal and nonsignificant decrease in sOC (-7.2%, p = 0.417) or sALP (-3.4%, p = 0.689), two specific markers of bone formation. As expected, due to the coupling of bone formation and bone resorption, the concentration of all markers showed a 30%-45% decline compared with baseline values after 90 days (n = 16) of treatment. Correlation of markers after a 30 day treatment with alendronate revealed a higher correlation (r = 0.61, p < 0.01) between uOC and uNTx, as compared with sOC (r = 0.03, p = 0.447) or sALP (r = -0.14, p = 0.295) with uNTx. Similarly, correlation coefficients with r values between 0.48 and 0.55 (p < 0.05) were observed between uOC, sNTx, and sCTx, whereas no significant correlation was observed between sOC and sNTx or sCTx. These results provide indirect evidence that fragments measured by the urine assay probably originated from bone resorption, and suggest that the uOC assay could be used to assess short-term changes in bone metabolism with regard to osteocalcin.

Concentrations of the bone resorption markers pyridinoline and deoxypyridinoline and the bone formation marker osteocalcin were measured in 24-h urine collections from 30 subjects who underwent unilateral total hip replacements for monoarticular symptomatic osteoarthrosis and 10 controls. The patient groups were divided based on the femoral implant type (cemented cobalt alloy stem, cementless porous coated cobalt alloy stem, and cementless porous coated titanium alloy stem). Urine collections were performed before surgery and then at 3, 6, 12, 24, and 36 months. There were significant changes over time in the three patient groups for pyridinoline, deoxypyridinoline, and the ratio of osteocalcin to deoxypyridinoline (p < or = 0.01), but the control group values did not change over time. The resorption markers tended to peak at 3 months and the osteocalcin to deoxypyridinoline ratio was more variable, having depressed values in the cementless cobalt alloy group and elevated values in the other two groups compared with baseline. The cementless cobalt alloy group had higher resorption marker levels than the cemented cobalt alloy group at 6, 12, 24, and 36 months and higher levels than the cementless titanium alloy group at all postoperative times (p < 0.05). The osteocalcin to deoxypyridinoline ratio was lower in the cementless cobalt alloy group than in the cemented cobalt alloy group at 3, 6, and 24 months and the cementless titanium alloy group at 6, 12, and 24 months (p < 0.05). For the cemented cobalt chrome group, the baseline-normalized resorption marker values at 3 months and 6 months were correlated with the severity of radiographically assessed bone loss at 36 months (0.749 < r < 0.840; p < 0.05). For the cementless titanium alloy group, baseline-normalized osteocalcin/ deoxypyridinoline ratios at 3 months and 6 months were related inversely to radiographic bone loss at 36 months (0.687 < r < 0.749; p < 0.05). Thus, body fluid markers of bone metabolism change after total hip replacement. In addition, the changes in the marker concentrations were sensitive to implant design and were correlated with subsequent stress-shielding-induced bone loss.

We investigated the effects of hormone replacement therapy (n = 27) on biochemical markers of bone turnover in a cross-sectional study of 127 postmenopausal women (according to WHO guidelines 18 patients had normal bone mineral density and 109 suffered from bone loss). Urinary excretion of free deoxypyridinoline and C- or N-telopeptide fragments of type I collagen served as bone resorption markers, serum osteocalcin as a bone formation marker. In women with no hormone replacement therapy, only C- and N-telopeptides correlated significantly with the lumbal T-score as an index for bone mineral density. Patients with bone loss receiving hormone replacement therapy exhibited significantly lower C-telopeptide, N-telopeptide and osteocalcin levels than those with no therapy (mean -45%, -43% and -26%, respectively), while deoxypyridinoline showed no significant differences. Among the markers investigated, C- and N-telopeptides seemed to be more reliable to detect therapeutic effects on bone metabolism. We present a preliminary model to evaluate bone turnover and resorption/formation rate.

Data are presented on the whole-body retention of 133Ba (half-life 10.74 y), over periods of up to 13 y after injection into six healthy male volunteers aged 25-81, and on their levels of biochemical markers for bone turnover. The results are relevant to propositions underlying the ICRP's current (Publication 67) and former (Publication 20) models of alkaline earth metabolism. The tracer was predominantly skeletal within weeks of the injection, as predicted in the current model. The mean retention accorded satisfactorily throughout with predictions based on the current model, but this accord does not necessarily validate the model, for two reasons. First, parameter values attributed to barium were influenced by data emerging during the early years of this study. Second, bone resorption rates in these subjects, as indicated by urinary markers, appear insufficient to explain the long-term reductions in skeletal retention which, in the present model, arise exclusively through this mechanism.

Aim: Bisphosphonates are potent inhibitors of osteoclastic activity and are used in the treatment of multiple myeloma (MM) in combination with chemotherapy. The effect of pamidronate on markers of bone resorption [cross-linked N-telopeptides of type I collagen (NTx)], markers of bone formation [serum alkaline phosphatase (BAP) and osteocalcin (OSC)], interleukin-6 (IL-6), beta2-microglobulin, CRP, paraprotein and disease-related pain and skeletal events has been evaluated in 62 newly diagnosed patients with MM., Patients and Methods: The patients were randomly assigned to two groups: the first included 32 patients under chemotherapy and pamidronate (group I) and the second 30 patients on chemotherapy only (group II). Pamidronate was administered at a monthly dose of 90 mg iv, and the above parameters were evaluated at the beginning of this study and after 1, 3, 6, 9, 12 and 14 months of treatment., Results: The addition of pamidronate to chemotherapy resulted in a significant reduction of NTx, IL-6 and paraprotein from the 3rd month and of beta2-microglobulin, CRP and pain from the 6th month of treatment. No changes of NTx, IL-6, beta2-microglobulin, CRP or skeletal events were observed in patients of group II, while paraprotein was significantly reduced after 6 months of treatment. The differences in NTx, IL-6, paraprotein and beta2-microglobulin were statistically significant between the two groups. Multivariate analysis revealed a significant correlation between changes of NTx, changes of IL-6 in both groups and reduction of pain and paraprotein in group I., Conclusions: These results suggest that pamidronate may have a synergistic action with chemotherapy in decreasing osteoclastic activity, in reducing markers of myeloma activity and myeloma related pain and in improving the quality of life in patients with MM.

Background: Microgravity induces bone loss by mechanism(s) that remain largely unknown., Methods: We measured biochemical markers related to bone remodeling in two cosmonauts before, during, and after 21- and 180-day space flights, respectively., Results: During both flights, type I procollagen propeptide and bone alkaline phosphatase decreased as early as 8 days after launch. Undercarboxylated osteocalcin percentage increased early and remained high during both flights. Vitamin K supplementation restored carboxylation of osteocalcin during the long-term flight. Urinary and serum C-telopeptide of type I collagen (CTX) increased as early as day 8 of the flights; the increase was greater in serum than in urine. Pyridinoline, free deoxypyridinoline, and N-telopeptide increased less than CTX during the short-term space flight. The circadian rhythm of bone resorption assessed by urine CTX and free deoxypyridinoline was not altered by microgravity., Conclusion: Vitamin K metabolism or action and bone remodeling may be altered in cosmonauts.

The aim of this study was to investigate bone mineral density (BMD) and bone turnover in patients with primary knee osteoarthritis (KOA) and to compare them with generalized OA (GOA) and nonGOA patients. A total of 88 postmenopausal primary KOA patients were studied. OA was graded by using knee radiographs. BMD of the lumber spine, femur, and radius, and biochemical markers of bone turnover, pyridinoline (Pyr), deoxypyridinoline (Dpyr), CTx, and osteocalcin were compared among each grade. BMD was also compared with 88 normal controls who were age and weight-matched. In 88 KOA patients, 56 were divided into 28 GOA and 28 non-GOA groups by grading hand radiographs. BMD and biochemical markers were compared between GOA and non-GOA. KOA patients had higher BMD at several skeletal sites compared with age- and weight-matched normals. A significant difference of BMD between each grade was observed between grades 0-1 and 3 (0.774+/-0.143 versus 0.940+/-0.185 g/cm(2), P<0.001), grades 2 and 3 (0.781+/-0.125 versus 0.940+/-0.185 g/cm(2), P<0.01) in the spine, and between grades 0-1 and 3 (0.505+/-0.100 versus 0.564+/-0.127 g/cm(2), P<0.05) in the trochanter. A significant difference of biochemical bone markers was observed between grades 0-1 and 3 (P<0.05) and between grades 2 and 3 (P<0.05) in Pyr and grades 0-1 and 3 (P<0.05) and between grades 1 and 4 (P<0.05) in Dpyr, but not in osteocalcin and CTx. GOA patients had higher BMD of the spine (0.902+/-0.175 versus 0.747+/-0.138 g/cm(2), P<0.01), trochanter (0.535+/-0.107 versus 0.480+/-0.107 g/cm(2), P<0.05), and one-third of the radius (0.526+/-0.068 versus 0.472+/-0. 089 g/cm(2), P<0.05) and had significantly higher biochemical markers in Pyr and Dpyr than non-GOA patients. It is concluded that KOA patients had higher BMD at several skeletal sites. Biochemical bone markers were influenced by some degree of cartilage damage in OA patients. This tendency was stronger in GOA patients than in non-GOA patients.

The development of new biochemical markers has made it possible to assess the effects of therapeutic agents on bone turnover more rapidly and precisely. In this early phase II study, we analyzed the effects of short-term, high-dose treatment with risedronate, a potent pyridinyl bisphosphonate, on markers of bone resorption and formation. Resorption markers included urinary free deoxypyridinoline (D-Pyr) crosslinks, N-terminal telopeptide (NTx) and C-terminal telopeptide (CTx) type I collagen crosslinks. Bone formation markers included osteocalcin (OC), bone-specific alkaline phosphatase (BSAP) and the C-terminal peptide of type I procollagen (PICP). All three resorption markers showed rapid, significant (p<0.05) decreases from baseline following daily administration of 30 mg risedronate for 2 weeks. The mean decreases at 2 weeks were 28% for D-Pyr, 61% for NTx and 73% for CTx, respectively. Over the next 10 weeks after treatment, D-Pyr approached baseline while NTx and CTx remained well below baseline values. The markers of bone formation showed little change during therapy but decreased significantly at 4-10 weeks after therapy - an expected outcome of bisphosphonate therapy. Moreover, there was a significant correlation between the early effects on bone resorption markers and the delayed effects on formation markers. This study demonstrates that the approved dose of risedonate (30 mg/day) for Paget's disease is effective at decreasing bone turnover after 2 weeks of treatment, as observed by the sensitive response of bone turnover markers.

The purpose of this investigation was to evaluate mineralized and non-mineralized connective tissue responses of non-human primates to microgravity by non-invasive analysis of urinary biomarkers.

Background: Phylloquinone, found in dark-green vegetables and certain plant oils, is the primary dietary source of the fat-soluble vitamin K. Limited data suggest that the relative bioavailability of phylloquinone from vegetables is lower than that from a supplement. This finding is relevant to the maintenance of optimal vitamin K status., Objective: The objective of this study was to compare, in younger and older adults, the relative bioavailability of phylloquinone from a vegetable with that of a fortified oil., Design: In a crossover design with three 15-d residency periods in a metabolic unit, younger and older men and women (n = 36) consumed a mixed diet containing 100 microg phylloquinone/d. During 2 residency periods, the mixed diet was supplemented for 5 d with either broccoli (377 microg phylloquinone/d; broccoli diet) or phylloquinone-fortified oil (417 microg/d; oil diet). The relative bioavailability of phylloquinone was defined by the difference in plasma phylloquinone, percentage serum undercarboxylated osteocalcin (%ucOC), and urinary gamma-carboxyglutamic acid in response to 5 d of supplementation., Results: For both younger and older adults, plasma phylloquinone concentrations were higher (P < 0.001) and %ucOC values were lower (P = 0.001) after the broccoli and oil diets than after the mixed diet only. Overall, the response to broccoli supplementation was not significantly different from the response to the fortified oil in either age group. Urinary gamma-carboxyglutamic acid did not change in response to supplementation., Conclusions: There was no significant difference in the relative bioavailability of phylloquinone, as evidenced by the lack of a significant difference in plasma phylloquinone and %ucOC between the 2 groups after either the broccoli or oil diets for younger and older adults.