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Incorporation of a human bone allograft requires osteoclast activity and growth of recipient osteoblasts. The aim of this work was to study the effects produced by autoclavated and −80°C frozen bone allografts on osteoblast proliferation and synthesis of interleukin 6 (IL6), activator of bone resorption, aminoterminal propeptide of procollagen I (PINP), marker of bone matrix formation, and osteoprotegerin (OPG), inhibitor of osteoclast activity and differentiation. Allografts were obtained from human femoral heads. Human osteoblasts were cultured in the presence (problem group) or in the absence (control group) of allografts during 15 days. Allografts produced a decrease in osteoblast proliferation in the first week of the experiment, and an increase in IL6 mRNA, both at 3 h and 2 days, and an increase in the IL6 released to the culture medium the second day of the experiment. We found a decrease in OPG released to the culture on the 2nd and fourth days. These results suggest an increase in bone resorption and a decrease in bone formation in the first week of the experiment. In the second week, allografts produced an increase in osteoblast proliferation and PINP release to the culture medium, indicating an increase in bone formation; an increase in OPG released to the culture medium, which would indicate a decrease in bone resorption; and a decrease in IL6, indicating a decrease in bone resorption stimulation. These results demonstrate that autoclavated and −80°C frozen bone allografts produce in bone environmemt changes that regulate their own incorporation to the recipient bone. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:200-207, 2008 [ABSTRACT FROM AUTHOR]

Background: Early detection of bone metastases in prostatic carcinoma is very useful in treatment and prognosis of the disease. The aim of this work was to evaluate the sensitivity and specificity of a group of bone markers in order to discriminate between prostate carcinoma patients without (M0) and with (M1) bone metastases. Methods: Sixty-seven non-treated patients with: benign prostate hyperplasia (n=21), prostatic carcinoma in several stages without bone metastases (TXM0) (n=31) and with bone metastases (TXM1) (n=15) were studied. The following markers were studied: (A) bone formation: (1) serum bone alkaline phosphatase, IRMA (Tandem Ostase, Beckman); (2) serum procollagen I amino-terminal propeptide (PINP), RIA (Orion Diagnostica); (B) bone resorption: (1) urinary collagen I amino-terminal telopeptide (NTX), ELISA (Ostex); (2) collagen I carboxy terminal telopeptide (CTX): (2A) urinary α-CTX, RIA (Osteometer), (2B) serum β-CTX, Elecsys (Roche); (3) collagen I cross-linked carboxy terminal telopeptide (ICTP), RIA (Orion Diagnostica). Results: Levels of all bone markers were significantly higher in group M1 than in group M0. A complete separation of groups M0 and M1 was achieved with PINP and β-CTX (100% sensitivity and specificity). Conclusions: These results support the use of PINP or β-CTX as a tool to confirm the presence or absence of bone metastases in the first staging of prostatic carcinoma patients. [Copyright &y& Elsevier]

Background We evaluated the evolution and predictive value of bone turnover markers (BTMs) and circulating tumor cells (CTCs) with respect to mortality, disease progression (DP) and skeletal-related events (SREs), in patients with bone metastatic breast cancer (BmBCa). The correlation between BTMs and CTCs was also studied. Methods In a 2-year observational, multicenter study, the levels of three BTMs (N- and C-terminal telopeptides of collagen I [NTX and αα-CTX], and bone-specific alkaline phosphatase [BSAP]) and CTCs were analyzed every three months. Patients received zoledronic acid (4 mg every 28 days) from the baseline visit. Results 234 patients were analyzed. The levels of the BTMs were increased at baseline and significantly decreased after 3 months ( P < 0.05). In the Cox regression univariate analyses significant hazard ratios (HRs) for death were found for pathological BSAP values at baseline (5.03 [95% CI: 1.214–20.839; P = 0.0259]) and at 3 months (3.41 [95% CI: 1.367–8.498; P = 0.0085]). HRs > 2 were found for increased baseline and 3-month levels of NTX and CTC ( P < 0.05). Only increased baseline BSAP levels were associated with DP (HR = 2.25 [95% CI: 1.391–3.626; P = 0.0009]). No biomarker was associated with SREs. In the multivariate analysis, pathologic levels at 3 months of NTX and BSAP were significantly associated with mortality (HRs = 3.59 [95% CI: 1.375–9.382; P = 0.0091] and 3.25 [95% CI: 1.293–8.189; P = 0.0120], respectively). CTC and BSAP were correlated during all study timepoints ( P < 0.05). Conclusions Baseline levels of NTX, BSAP and CTCs, and changes after treatment initiation with bisphosphonates, may be useful for the prognostic assessment of patients with BmBCa. BSAP showed the strongest prognostic value. [ABSTRACT FROM AUTHOR]

Aim: The aim of this work is to compare the effects of osteoprotegerin (OPG) and testosterone on bone quality in a model of orchidectomised (ORX) rats.Methods: Three-month-old ORX or SHAM operated groups (n = 15 each group) were used. The SHAM and ORX groups received saline. There were two ORX groups, receiving OPG-Fc (10 mg/kg twice weekly) (ORX + OPG-Fc) or testosterone cypionate (1.7 mg/kg/weekly) for 8 weeks. After sacrifice, bone analysis by femoral and lumbar dual-energy X-ray absorptiometry and micro-computed tomography in femora were performed. Histological sections of vertebrae were dyed with hematoxylin-eosin or safranin. Serum osteocalcin (BGP), total alkaline phosphatase (ALP), and C-terminal telopeptide of type I collagen (CTX) were analyzed.Results: ORX resulted in femoral and vertebral bone loss and in microarchitectural deterioration. Treatment with OPG-Fc and testosterone recovered lumbar (L) and femoral (F) bone mineral densitometry bone mineral density (BMD) to SHAM levels. Femoral BMD was significantly higher after treatment with OPG-Fc than after testosterone treatment due to the presence of osteopetrotic changes in the metaphyseal region of long bones. Serum levels of ALP and CTX increased, while OPG levels were unchanged in ORX rats. Treatment with OPG-Fc decreased the levels of BGP, ALP, and CTX. Treatment with testosterone maintained biochemical markers of bone turnover at levels similar to or higher than those of ORX rats. [ABSTRACT FROM AUTHOR]

Background: The mortality of dialysis patients is 10- to 100-fold higher than in the general population. Baseline serum PTH levels, and more recently, changes in serum PTH levels (ΔPTH) over time, have been associated to mortality in dialysis patients. Methods: We explored the relationship between ΔPTH over 1 year with mortality over the next year in a prospective cohort of 115 prevalent hemodialysis patients from a single center that had median baseline iPTH levels within guideline recommendations. Results: Median baseline iPTH levels were 205 (116.5, 400) pg/ml. ΔiPTH between baseline and 1 year was 85.2 ± 57.1 pg/ml. During the second year of follow-up, 27 patients died. ΔiPTH was significantly higher in patients who survived (+157.30 ± 25.82 pg/ml) than in those who died (+39.03 ± 60.95 pg/ml), while baseline iPTH values were not significantly different. The highest mortality (48%) was observed in patients with a decrease in ΔiPTH (ΔiPTH quartile 1, negative ΔiPTH) and the lowest (12%) mortality in quartile 3 ΔiPTH (ΔiPTH increase 101–300 pg/ml). In a logistic regression model, ΔiPTH was associated with mortality with an odds ratio (OR) of 0.998 (95% CI 0.996–0999, p = 0.038). In multivariable analysis, mortality risk was 73% and 88% lower for patients with ΔiPTH 0–100 pg/ml and 101–300 pg/ml, respectively, than for those with a decrease in ΔiPTH. In patients with a decrease in ΔiPTH, the OR for death was 4.131 (1.515–11.27)(p = 0.006). Conclusions: In prevalent hemodialysis patients with median baseline iPTH values within the guideline recommended range, a decrease in ΔiPTH was associated with higher mortality. Further studies are required to understand the mechanisms and therapeutic implications of this observation that challenges current clinical practice. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to determine whether there is a relationship between iron status and bone metabolism, and to compare the effects of the consumption, as part of the usual diet, of an iron or iron and vitamin D-fortified skimmed milk on bone remodelling in iron-deficient women. Methods: Young healthy iron-deficient or iron-sufficient women (serum ferritin ≤30 ng/mL or >30 ng/mL, respectively) were recruited. Iron-deficient women were assigned to a nutritional intervention consisting of a randomised, controlled, double-blind, parallel design trial of 16 weeks during winter. They consumed, as part of their usual diet, an iron (Fe group, n = 54) or iron and vitamin D-fortified (Fe+D group, n = 55) flavoured skimmed milk (iron, 15 mg/day; vitamin D, 5 μg/day, 200 IU). The iron-sufficient women followed their usual diet without supplementation (R group, n = 56). Dietary intake, body weight, iron biomarkers, 25-hydroxyvitamin D (25OHD), parathyroid hormone (PTH), procollagen-type 1 N-terminal propeptide (P1NP), and aminoterminal telopeptide of collagen I (NTx) were determined. Results: Negative correlations were found between baseline log-ferritin and log-NTx ( p < 0.001), and between transferrin and P1NP ( p = 0.002). Serum 25OHD increased (from 62 ± 21 to 71 ± 21 nmol/L, mean ± SD, p < 0.001) while P1NP and NTx decreased in Fe+D during the assay ( p = 0.004 and p < 0.001, respectively). NTx was lower in Fe+D compared to Fe at week 8 ( p < 0.05) and was higher in Fe and Fe+D compared to R throughout the assay ( p < 0.01). PTH did not show changes. Conclusions: Iron deficiency is related with higher bone resorption in young women. Consumption of a dairy product that supplies 5 μg/day of vitamin D reduces bone turnover and increases circulating 25OHD to nearly reach an optimal vitamin D status, defined as 25OHD over 75 nmol/L. [ABSTRACT FROM AUTHOR]

Aim: The purpose of this study was to evaluate the effect of parathyroid hormone (PTH) (1-84) in a model of male osteoporosis induced by orchidectomy in rats. Methods: Six-month-old Wistar rats were used as follows: SHAM (simulated orchidectomy), orchidectomized (ORX), ORX + PTH1 (ORX and treated with 10 µg/Kg/d of PTH 1-84) and ORX + PTH2 (ORX and treated with 50 µg/Kg/d of PTH 1-84) over 3 months, with treatment beginning three months after orchidectomy. Results: Orchidectomy resulted in a decreased of femoral and lumbar bone mineral density (BMD), a worsening of trabecular and cortical microarchitecture and a decrease in biomechanical properties. Both doses of PTH (1-84) partially (low dose) or totally (high dose) restored the ORX-induced changes. Serum C-telopeptide of type I collagen/5b isoenzyme of tartrate-resistant acid phosphatase (CTX/TRAP) resorption index increased after orchidectomy. Osteocalcin (bone Gla protein; BGP) levels were not affected by orchidectomy. PTH (1-84) treatment did not produce any changes in the levels of CTX/TRAP with respect to the ORX group. BGP levels increased with PTH treatment. Conclusion: PTH (1-84) is able to restore the adverse effects of orchidectomy on bone as measured by BMD, microstructural and biomechanical properties and bone remodeling markers. [ABSTRACT FROM AUTHOR]

Background: Iron and vitamin D deficiencies are two of the most widespread nutritional disorders in the world. Our aim was to know whether the consumption of an iron-fortified fruit juice modifies bone remodelling and the possible influence of baseline vitamin D status on the recovery of iron status in a group of iron-deficient women. Methods: Iron biomarkers, 25-hydroxyvitamin D levels and dietary intake were measured in 123 iron-deficient menstruating women. A subgroup ( n = 41) participated in a randomised double-blind placebo-controlled study of 16-weeks during winter. They consumed a placebo fruit juice (P) or iron-fortified fruit juice (F). Dietary intake, 25-hydroxyvitamin D, parathormone (PTH), bone alkaline phosphatase (ALP), aminoterminal telopeptide of collagen I (NTX) and iron biomarkers were determined. Results: Ninety-two per cent of the iron-deficient women were vitamin D deficient or insufficient. Transferrin saturation and 25-hydroxyvitamin D were positively correlated. Iron status improved in F, 25-hydroxyvitamin D decreased in F and P, and PTH, ALP and NTX levels were within the normal range and did not vary. Women with 25-hydroxyvitamin D ≥ 50 nmol/L compared with 25-hydroxyvitamin D < 50 nmol/L showed a higher increase in transferrin saturation (a marker of iron supply to tissues) during iron recovery. Conclusion: The prevalence of vitamin D deficiency or insufficiency is very high in iron-deficient women. The recovery of iron status by consuming an iron-fortified food does not affect 25-hydroxyvitamin D levels; however, the increase in iron supply to tissues is lower if the women also present vitamin D deficiency. Although bone health does not seem to be affected in this group of women, correction of iron and vitamin D deficiencies should be promoted in young women to improve present and future health. [ABSTRACT FROM AUTHOR]

Abstract: Recent evidence suggests that miRNAs could be used as serum markers in a variety of normal and pathological conditions. In this study, we aimed to identify novel miRNAs associated with skeletal metastatic disease in a preclinical model of lung cancer bone metastasis. We assessed the validity of these miRNAs as reliable serum biochemical markers to monitor the extent of disease and response to treatment in comparison to imaging techniques and standard biochemical markers of bone turnover. Using a murine model of human lung cancer bone metastasis after zoledronic acid (ZA) treatment, PINP (procollagen I amino-terminal propeptide) was the only marker that exhibited a strong correlation with osteolytic lesions and tumor burden at early and late stages of bone colonization. In contrast, BGP (osteocalcin) and CTX (carboxyterminal telopeptide) demonstrated a strong correlation only at late stages. We performed qPCR based screening of a panel of 380 human miRNAs and quantified bone metastatic burden using micro-CT scans, X-rays and bioluminescence imaging. Interestingly, levels of miR-326 strongly associated with tumor burden and PINP in vehicle-treated animals, whereas no association was found in ZA-treated animals. Only miR-193 was associated with biochemical markers PINP, BGP and CTX in ZA-treated animals. Consistently, miR-326 and PINP demonstrated a strong correlation with tumor burden. Our findings, taken together, indicate that miR-326 could potentially serve as a novel biochemical marker for monitoring bone metastatic progression. [Copyright &y& Elsevier]

To characterize an experimental model of osteoporosis in rabbits induced either by ovariectomy (OVX), glucocorticoids, or by a combination of both. Thirty-five rabbits were randomly allocated into five groups: bilateral OVX, daily methylprednisolone hemisuccinate (MPH) injections at a 1.5 mg/kg/day dose for 4 consecutive weeks (MPH group), or variable dose of MPH between 0.5 and 2 mg/kg/day in combination with OVX (OVX + MPH at low, medium, and high dose). Twenty-two animals were killed 6 weeks after OVX, and 13 were killed 16 weeks later. Dual-energy X-ray absorptiometry was obtained at baseline and 6 and 16 weeks after OVX. High-resolution magnetic resonance imaging (MRI) was carried out at 0 and 6 weeks after OVX. Glucose, total cholesterol, triglyceride, and oestradiol blood levels before and 16 weeks after OVX were determined. Bone mineral density (BMD) decreased significantly at lumbar spine in MPH and OVX + MPH medium-dose groups, and at global knee and subchondral bone of the knee in MPH, OVX + MPH low- and medium-dosage groups (P < 0.05). BMD variations in OVX rabbits were not significant in any of the three anatomical locations analyzed. BMD variation 16 weeks after OVX was significant at lumbar spine and global knee in the OVX + MPH medium-dose group and only at global knee in the OVX + MPH low-dose group (P < 0.05). MRI did not show bone or cartilage changes. Osteoporosis can be induced experimentally in rabbits through isolated MPH or by a combination of OVX and medium dose corticosteroid for 4 weeks. OVX alone was not sufficient to induce osteoporosis. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this work was to analyze the effects produced on bone mineral density (BMD) by the administration of bicalutamide and to compare them with those produced by orchidectomy. Bone formation rate (serum osteocalcin), bone resorption (serum carboxyterminal telopeptide of collagen I; CTX), and biomechanical properties of bone were also studied. Methods: Thirty-eight male Wistar rats were used: (1) Sham group, rats sham operated at 16 weeks of age; (2) OQX group, rats orchidectomized at 16 weeks of age, and (3) Bic group, rats sham operated at 16 weeks of age and treated during 6 weeks with bicalutamide. The rats were sacrificed at 22 weeks of age, and the BMD in femur and lumbar spine was determined. Serum osteocalcin and serum CTX were also analyzed. Biomechanical parameters related to torsion assay were also studied. Results: The OQX group showed a significant decrease in femoral BMD with respect to Sham rats, whereas bicalutamide treatment did not produce any significant change in BMD. Both Sham and Bic groups showed similar serum osteocalcin and CTX values, whereas OQX rats presented higher osteocalcin and CTX levels than the Sham group. The OQX group showed a significant decrease in femoral thickness. No significant differences were observed in the rest of the biomechanical parameters between groups. Conclusion:These results indicate that bicalutamide treatment, in spite of its anti-androgenic properties, does not affect bone remodelling nor BMD in male healthy rats, suggesting that this compound may function as a selective androgen receptor modulator for effects on bone remodelling in the osteoblasts. Copyright © 2005 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]