Serum Bone-specific Alkaline Phosphatase Research Articles

Role of B12 and Homocysteine Status in Determining BMD and Bone Turnover in Young Indians

Vitamin B12 (B12) deficiency and hyperhomocysteinemia (HHcy) are independent risk factors for low bone mineral density (BMD) and fracture risk. We studied the role of HHcy and B12 deficiency in determining the peak bone mass in Indians. Randomly selected 151 healthy young adult subjects (females 100, mean age: 26yr) underwent evaluation of dietary intake of calcium and B12; sun exposure; estimation of BMD by dual-energy X-ray absorptiometry at total hip, forearm, and lumbar spine; serum 25(OH)D3; intact parathyroid hormone; B12; homocysteine (Hcy); and bone turnover markers (BTMs) serum crosslaps, N-mid osteocalcin, and bone-specific alkaline phosphatase. Hypovitaminosis D (serum 25OHD3<20ng/mL) and serum ALP level >150IU/L were seen in 83% and 27%, respectively. Median serum B12 and Hcy levels were 140pg/mL (interquartile range [IQR]: 72–230pg/mL) and 18μmol/L (IQR 14–32μmol/L); B12 deficiency (serum B12<200pg/mL) and HHcy (serum Hcy>30μmol/L) were present in 71% and 68%, respectively. Low BMD (Z-score <−2.0) was present in 17% of subjects. There was no significant correlation between serum Hcy, folate, B12, BTM, and BMD. BMD was predicted by height, weight, and body mass index. Young Indian healthy adults have high prevalence of hypovitaminosis D, B12 deficiency, and HHcy. There is no correlation of serum B12, folate, and Hcy status with BTMs and BMD in young, healthy, vegetarian Indian adults. Anthropometric variables predict BMD in young Indians.

Bone turnover markers predict changes in bone mineral density after parathyroidectomy in patients with renal hyperparathyroidism

Patients on long-term dialysis may develop secondary hyperparathyroidism (SHPT), which causes varying degrees of bone mass loss. This condition is treated with parathyroidectomy (PTX). We investigated whether serial serum bone turnover markers could predict changes in bone mineral density (BMD) after PTX. Renal patients on maintenance haemodialysis who received PTX for refractory SHPT (n = 26, male/female: 13/13; mean age: 48·6 ± 10·7 year) and control subjects without SHPT (n = 25) were prospectively followed for 1 year at two tertiary hospitals in Taiwan. Serum intact parathyroid hormone (iPTH), bone-specific alkaline phosphatase (BAP) and type 5b tartrate-resistant acid phosphatase (TRAP) were measured serially. Additionally, femoral neck (FN) and lumbar spine (LS) BMD were measured before and 1 year after PTX. After PTX, iPTH levels decreased markedly and persistently. BMDs increased in both the FN and LS, but particularly in the LS. Serum BAP progressively increased to a peak at 2 weeks after PTX. Serum TRAP levels progressively decreased over 6 months after PTX. In univariate correlation analyses, baseline iPTH correlated positively with T-score changes in FN (r = 0·45, P = 0·021) and LS (r = 0·48, P = 0·013). In multivariate regression models, changes in FN T-scores were negatively predicted by baseline BAP levels (r = -0·615, P = 0·005) and baseline FN T-scores (r = -0·563, P = 0·012), and they were positively predicted by baseline TRAP(r = 0·6, P = 0·007). Changes in LS T-scores were positively predicted by baseline TRAP values (r = 0·528, P = 0·01) and negatively predicted by the percentage change in BAP after 2 weeks (r = -0·501, P = 0·015). Parathyroidectomy provided marked, sustained improvements in BMD for up to 1 year. Furthermore, markers of bone turnover predicted 1-year changes in FN and LS BMDs after PTX.

Age associated change in biomarkers of bone metabolism in cats

Age associated change in bone metabolism in cats was investigated by measuring biomarkers of bone metabolism in a cross sectional study. Serum and urine samples were collected from 96 healthy American domestic shorthair cats (29 males and 67 females) with ages ranging from 1.7 to 15.9 years old after they were fed a dry cat food for at least 3 weeks. Following biomarkers were measured: procollagen type II C‐propeptide (PIICP), C‐terminal cleavage products of type II collagen (C2C), C‐terminal telopeptide of type II collagen fragments (CTX II), Type IIA collagen N‐propeptide (PIIANP), N‐terminal cross‐linked telopeptide of type I collegen (NTx), keratan sulfate (KS), chondroitin sulfate epitope 846 (CS846), and bone specific alkaline phosphatase (BAP). Linear correlation coefficient between age and measured biomarkers was calculated.Serum BAP (r=−0.19, p=0.01) and urine CTX II (r=−0.47, p&lt;0.01) were negatively and serum C2C (r=0.37, p&lt;0.01) and KS (r=0.35, p&lt;0.01) were positively associated with age. Both serum BAP and urine CTX II were significantly higher in cats &lt; 2 years old, suggesting that bone metabolism does not attain maturity in cats until they are 2 years old. No association between age and other measured biomarkers was observed in cats &gt; 1 year old.

Strontium fructose 1,6-diphosphate prevents bone loss in a rat model of postmenopausal osteoporosis via the OPG/RANKL/RANK pathway

To evaluate the protective effects of strontium fructose 1,6-diphosphate (FDP-Sr), a novel strontium salt that combined fructose 1,6-diphosphate (FDP) with strontium, on bone in an ovariectomy-induced model of bone loss. Eighty female Sprague-Dawley rats were ovariectomized (OVX) or sham-operated. Three months later, the rats were assigned to six groups (10 for each): sham-operated, OVX control, OVX+FDP-Sr (110, 220, or 440 mg/kg), or OVX+strontium ranelate (SR, 180 mg/kg). Drugs were administered orally for 3 months. When the treatment was terminated, the following parameters were assessed: bone mineral density (BMD), the biomechanical properties of the femur and lumbar vertebrae, trabecular histomorphology, serum phosphorus, calcium, bone-specific alkaline phosphatase (B-ALP), tartrate-resistant acid phosphatase 5b (TRACP5b), N-telopeptide of type I collagen (NTx) and a series of markers for oxidative stress. Receptor activator of NF-κB ligand (RANKL) and osteoprotegerin (OPG) levels in serum were measured using ELISA and their gene expression levels in the bone were measured using R-T PCR. Treatment with FDP-Sr (220 or 440 mg/kg) or SR (180 mg/kg) significantly increased the BMD and improved the bone microarchitecture and bone strength in OVX rats. The treatments also decreased in the levels of H(2)O(2) and MDA, restored the CAT level in serum and bone marrow, increased the serum B-ALP and decreased NTx and TRACP 5b in OVX rats. Treatment with FDP-Sr decreased the RANKL level, and increased the OPG level in serum in a dose-dependent manner. It also significantly down-regulated the RANKL expression and up-regulated OPG expression in bone marrow. FDP-Sr may be an effectve treatment for postmenopausal osteoporosis that acts, in part, via a decrease in osteoclastogenesis through the OPG\RANKL\RANK pathway.

Electroacupuncture Prevents Ovariectomy-Induced Osteoporosis in Rats: A Randomised Controlled Trial

Electroacupuncture (EA) treatment has been shown to increase bone mineral density (BMD) in ovariectomised (OVX) rats; however, the underlying mechanisms remain unclear. To systematically evaluate the effects of EA on OVX rats and the Wnt/β-catenin signalling pathway. Three-month-old female Sprague-Dawley rats were randomly divided into three different groups (n=10 each): sham operated control (sham operated), ovariectomy (OVX) and ovariectomy with EA treatment (OVX+EA). Rats in the OVX+EA group received 12-week EA treatments. Serum bone-specific alkaline phosphatase level (p<0.01), BMD of the proximal femoral metaphysis and the fifth lumbar (L5) vertebral body (both, p<0.05) and maximum load and energy to failure of L5 vertebral body (both p<0.01) were significantly higher in the OVX+EA group than in the OVX group. Trabecular area, trabecular width and trabecular number were significantly higher in the OVX+EA group by 66.9%, 29.2% and 30.3%, respectively, than in the OVX group (all, p<0.01). Trabecular separation was 31.9% lower in the OVX+EA group than in the OVX group (p<0.01). Quantitative real-time reverse transcription polymerised chain reaction indicated that the expressions of mRNAs for low-density lipoprotein receptor-related protein 5 and β-catenin were significantly increased in the OVX+EA group, as compared with the OVX group (p<0.01 and p<0.05, respectively). This study demonstrates that EA can prevent OVX-induced bone loss and deterioration of bone architecture and strength by stimulating the Wnt/β-catenin signalling pathway. These findings suggest that EA may bet a promising adjunct method for inhibiting OVX-induced osteoporosis in clinical settings.

Parathyroidectomy leads to decreased blood lead levels in patients with refractory secondary hyperparathyroidism

ObjectiveSecondary hyperparathyroidism (SHPT) is characterized by high bone turnover and may result in increased release of lead (Pb) from bone stores. Parathyroidectomy (PTX) drastically changes bone remodeling. This study investigated the effects of PTX on the levels of blood lead (blood Pb) in patients with refractory SHPT. MethodsThe study included 30 patients on long-term hemodialysis (HD) who underwent PTX in the nephrology units of two Taiwanese hospitals. Changes in serum levels of intact parathyroid hormone (iPTH), bone-specific alkaline phosphatase (BAP), type 5b tartrate-resistant acid phosphatase (TRAP), total calcium (tCa), and blood Pb were analyzed. ResultsAfter PTX, serum iPTH was markedly decreased while serum BAP was progressively increased and peaked 2weeks after PTX. Serum TRAP levels were progressively decreased during the 4week follow-up period. Serum tCa and blood Pb levels decreased sharply immediately after PTX. There was a positive correlation between the percentage of decrease in tCa and blood Pb at one day after PTX. Further analysis indicated a significant positive correlation between levels of blood Pb and serum iPTH (r=0.378, p<0.001), blood Pb and serum TRAP (r=0.180, p<0.05), and a negative correlation between blood Pb and serum BAP (r=−0.205, p<0.05). ConclusionPTX effectively suppressed the elevated levels of blood Pb and serum bone remodeling markers, which are common features of SHPT. In addition to decreased Pb release from bone, an increased store of Pb in bone may play a role in decreasing serum blood Pb levels. These findings suggest that patients undergoing PTX for refractory SHPT should strictly avoid environmental exposure to Pb.

Serum N-Telopeptide and Bone-Specific Alkaline Phosphatase Levels in Patients With Osteonecrosis of the Jaw Receiving Bisphosphonates for Bone Metastases

Oversuppression of bone turnover can be a critical factor in the pathogenesis of osteonecrosis of the jaw (ONJ). We investigated N-telopeptide of type I collagen (NTX) and bone-specific alkaline phosphatase (BAP) as potential predictors of ONJ onset. Patients with ONJ and available stored serum were identified retrospectively from the institutional databases. Four approximate points were examined: point of ONJ diagnosis and 12, 6, and 1 month before the diagnosis. NTX and BAP were measured using enzyme-linked immunosorbent assays and examined as possible predictors of ONJ. From March 1998 to September 2009, we identified 122 patients with ONJ. Of these, 56 (46%) had one or more serum samples available. Overall, 55 patients (98%) received bisphosphonates. Using the exact dates, no obvious patterns in either NTX or BAP were noted. Similarly, using the ordinal points, no evidence of suppression of NTX or BAP over time was seen. The consecutive median values were as follows: The median NTX values were 8.0 nmol/L (range 3.8 to 32.9) at 12 months before ONJ; 9.5 nmol/L (range 4.7 to 42.7) at 6 months; 9.5 nmol/L (range 4.5 to 24.6) at 1 month, and 10.4 nmol/L (range 4.4 to 32.5) at the ONJ diagnosis. The median BAP values were BAP 18.0 U/L (range 7.0 to 74) at 12 months before ONJ; 18.0 U/L (range 4.0 to 134) at 6 months; 14.0 U/L (range 4.0 to 132) at 1 month, and 18.0 U/L (range 0.7 to 375) at the ONJ diagnosis. Only 2 patients (4%) had NTX and 17 (30%) had BAP below the normal range at the ONJ diagnosis. In the present large retrospective study, no trends were seen in the NTX and BAP levels before the ONJ diagnosis.

Effects of vitamin E on bone turnover markers among US postmenopausal women

Increased oxidative stress and inflammation resulting from aging and declining estrogen levels can lead to increased bone loss in postmenopausal women. Alpha-tocopherol and gamma-tocopherol, the two predominant isomers of vitamin E, have antioxidant and anti-inflammatory properties, but their effects on bone metabolism have not been well studied in humans. We examined the associations between dietary and total (diet and supplements) alpha-tocopherol intake, serum alpha-tocopherol and gamma-tocopherol levels and their ratio, and bone turnover markers (BTMs) among postmenopausal women aged ≥45 years. We used cross-sectional data from the National Health and Nutrition Examination Survey 1999–2002. Multiple regression models with adjustments for relevant confounders were used to examine the associations between intake and serum levels of tocopherols, and serum bone-specific alkaline phosphatase (BAP), a biomarker of bone formation, and urinary N-telopeptides/creatinine (uNTx/Cr), a biomarker of bone resorption. The study sample included 497 postmenopausal women who were not taking estrogen, steroids, or osteoporosis medications, were free from kidney and liver disease, cancer, and rheumatoid arthritis, and were fasting >9 hours prior to examination. Participants had a mean age of 65.5 ± 0.6 years and over 45% used vitamin E (alpha-tocopherol) supplements in the past month. Vitamin E supplement users had significantly lower serum gamma-tocopherol, higher serum alpha-tocopherol levels, and higher ratio of serum alpha-tocopherol to gamma-tocopherol than nonusers. High serum gamma-tocopherol levels and low ratio of serum alpha-tocopherol to gamma-tocopherol were associated with increased BAP levels (p < 0.01 for both). There were no associations between any of the vitamin E variables and uNTx/Cr. In conclusion, we hypothesize that gamma-tocopherol may uncouple bone turnover, resulting in more bone formation than resorption. Vitamin E supplements in the form of alpha-tocopherol suppress serum gamma-tocopherol levels and may have negative effects on bone formation. Further research is needed to investigate the potential anabolic effect of gamma-tocopherol from food sources on bone.

A Study of the Association between Serum Bone-Specific Alkaline Phosphatase and Serum Phosphorus Concentration or Dietary Phosphorus Intake

Alkaline phosphatase (ALP) hydrolyzes a variety of monophosphate esters into phosphoric acid and alcohol at a high optimum pH (pH 8-10). Human ALPs are classified into four types: tissue-non specific (TNSALP, liver/bone/kidney), intestinal, placental, and germ cell types. Based on studies of hypophosphatasia (HPP), which is a systemic bone disease caused by the presence of either one or two pathologic mutations in ALPL that encodes TNSALP, TNSALP was suggested to be indispensable for skeletal mineralization. In this study, we explored the possibility that dietary nutrients contribute to regulate serum bone-specific ALP (BAP) activity. Serum biochemical parameters, such as serum ALP, BAP, osteocalcin, and fibroblast growth factor 23 (FGF23), were measured in healthy young subjects (n=193). Dietary nutrient intakes were measured based on 3-d food records before the day of blood examinations. The presence of a carrier of the deletion of T at nucleotide 1559 (c.1559delT), which has been reported to be the most frequent in Japanese HPP, was not detected in any subject. By the analysis of BAP activity and other biochemical parameters or dietary nutrient intakes, we obtained significant correlations between BAP activity and serum phosphorus (r=-0.165, p=0.022), calcium intake (mg/1,000 kcal/d) (r=-0.186, p=0.010), or phosphorus intake (mg/1,000 kcal/d) (r=-0.226, p=0.002). Further study on the regulation of BAP activity and calcium and/or phosphorus homeostasis will provide useful data for improving skeletal health.

Wnt-signaling-mediated antiosteoporotic activity of porcine placenta hydrolysates in ovariectomized rats.

Anti-osteoporotic effects of two types of porcine placenta hydrolysates (PPH) were evaluated in ovariectomized (OVX) rats orally administered PPH without (WPPH) or with (NPPH) ovarian hormones (1 g/kg bw/day). PPH groups were compared with OVX rats with estrogen replacement (0.1 mg/kg bw conjugated estrogen; EST), or dextrose (placebo; OVX-control) All rats received high-fat/calcium-deficient diets for 12 weeks. NPPH contained less estrogen and progesterone, but more essential amino acids, whereas the opposite was true for WPPH. NPPH decreased body weight and peri-uterine fat pads, and maintained uterus weight. NPPH rats had higher femur and lumbar spine bone mass density compared to controls; but less than those of EST rats. Serum phosphorus and urinary calcium and phosphorus levels were reduced in NPPH rats compared to OVX-controls. Serum bone-specific alkaline phosphatase, osteocalcin, and bone turnover marker levels were reduced NPPH rats compared to OVX-controls. WPPH produced results similar to those of NPPH, but less significant. Both NPPH and estrogen upregulated low-density lipoprotein receptor-related protein 5 and β-catenin in OVX rats, while the expression of dickkopf-related protein 1 was suppressed. In conclusion, NPPH exerted anti-osteoporotic effects by activating osteogenesis and stimulating Wnt signaling, possibly mediated by the various amino acids and not ovarian hormones.

Potential role of odanacatib in the treatment of osteoporosis

Cathepsin K is a key enzyme involved in the degradation of organic bone matrix by osteoclasts. Inhibition of bone resorption observed in human and animal models deficient for cathepsin K has identified this enzyme as a suitable target for intervention by small molecules with the potential to be used as therapeutic agents in the treatment of osteoporosis. Odanacatib (ODN) is a nonbasic selective cathepsin K inhibitor with good pharmacokinetic parameters such as minimal in vitro metabolism, long half-life, and oral bioavailability. In preclinical studies, ovariectomized monkeys and rabbits treated with ODN showed substantial inhibition of bone resorption markers along with increases in bone mineral density (BMD). Significant differences were observed in the effects of ODN treatment compared with those of other antiresorptive agents such as bisphosphonates and denosumab. ODN displayed compartment-specific effects on trabecular versus cortical bone formation, with treatment resulting in marked increases in periosteal bone formation and cortical thickness in ovariectomized monkeys whereas trabecular bone formation was reduced. Furthermore, osteoclasts remained viable. Phase I and II studies conducted in postmenopausal women showed ODN to be safe and well tolerated. After 5 years, women who received ODN 50 mg weekly continuously from year 1 (n = 13), showed BMD increases from baseline of 11.9% at the lumbar spine, 9.8% at the femoral neck, 10.9% at the hip trochanter, and 8.5% at the total hip. Additionally, these subjects maintained a low level of the urine bone resorption marker N-terminal telopeptide/creatinine (−67.4% from baseline) through 5 years of treatment, while levels of serum bone-specific alkaline phosphatase remained only slightly reduced relative to baseline (−15.3%). In women who were switched from ODN to placebo after 2 years, bone turnover markers were transiently increased and BMD gains reversed after 12 months off medication. Adverse experiences in the ODN-treated group were not significantly different from the placebo group. In conclusion, available data suggests that cathepsin K inhibition could be a promising intervention with which to treat osteoporosis. Ongoing studies are expected to provide information on the long-term efficacy in fracture reduction and safety of prolonged treatment with ODN.

Bone turnover in preeclampsia-complicated pregnancy in North Indian women.

This prospective study aims to investigate the levels of bone turnover markers in pregnancy and correlate it with the assessment of preeclampsia. A total of 140 women were followed up during their pregnancy. The women who developed preeclampsia (n=22), were compared with age-matched women (controls) who did not develop preeclampsia and had an uncomplicated pregnancy (n=22). Maternal serum levels of serum bone-specific alkaline phosphatase (sBAP), a marker of bone formation, and N-telopeptide of type 1 collagen (NTx), a marker of bone resorption, were estimated at recruitment (in the second trimester) and at delivery. sBAP and NTx levels were measured by enzyme immunoassay (EIA) and enzyme linked immunosorbent assay (ELISA), respectively. Serum and urinary calcium titers were compared by using a commercially-available calcium assay kit. Serum NTx levels increased significantly during pregnancy (P<0.02) and were significantly higher at delivery (P<0.01) in women with preeclampsia compared with controls. The levels of sBAP and serum calcium did not change significantly in both groups during pregnancy. There was no significant correlation between sBAP and NTx with maternal factors. A negative correlation was observed between sBAP and NTx levels in the preeclamptic group. Biochemical markers of bone turnover are greater in preeclampsia compared with normal pregnancy only when the disease is clinically evident (at delivery).

The effect of soy isoflavone on bone mineral density in postmenopausal Taiwanese women with bone loss: a 2-year randomized double-blind placebo-controlled study

SummaryThe treatment of 300-mg/day isoflavones (aglycone equivalents) (172.5 mg genistein + 127.5 mg daidzein) for 2 years failed to prevent lumbar spine and total proximal femur bone mineral density (BMD) from declining as compared with the placebo group in a randomized, double-blind, two-arm designed study enrolling 431 postmenopausal women 45–65 years old.IntroductionThis study evaluated the effects of soy isoflavones on bone metabolism in postmenopausal women.MethodsFour hundred and thirty-one women, aged 45–65 years, orally consumed 300-mg/day isoflavones (aglycone equivalents) or a placebo for 2 years in a parallel group, randomized, double-blind, two-arm study. Each participant also ingested 600 mg of calcium and 125 IU of vitamin D3 per day. The BMD of the lumbar spine and total proximal femur were measured using dual-energy X-ray absorptiometry at baseline and every half-year thereafter. Serum bone-specific alkaline phosphatase, urinary N-telopeptide of type 1 collagen/creatinine, and other safety assessments were examined regularly.ResultsTwo hundred out of 217 subjects in the isoflavone group and 199 out of 214 cases in placebo group completed the treatment. Serum concentrations of isoflavone metabolites, genistein and daidzein, of the intervention group were remarkably elevated following intake of isoflavones (p < 0.001). However, differences in the mean percentage changes of BMD throughout the treatment period were not statistically significant (lumbar spine, p = 0.42; total femur, p = 0.39) between the isoflavone and placebo groups, according to the generalized estimating equation (GEE) method. A significant time trend of bone loss was observed at both sites as assessed by the GEE method following repeated measurement of BMD (p < 0.001). Differences in bone marker levels were not significant between the two treatment groups.ConclusionTreatment with 300-mg/day isoflavones (aglycone equivalents) failed to prevent a decline in BMD in the lumbar spine or total femur compared with the placebo group.

Vitamin D Status and Indices of Bone Turnover in Older European Adults

An increased rate of bone turnover increases risk of osteoporotic fracture later in life. The concentration of 25-hydroxyvitamin D that contributes to an elevated rate of bone turnover in older adults is unclear. The objective of this study was to investigate the associations between 25-hydroxyvitamin D and biochemical markers of bone turnover in an older, pan-European cohort. 25-hydroxyvitamin D and serum markers of bone-formation (osteocalcin and bone-specific alkaline phosphatase) were assessed by ELISA, while urinary markers of bone-resorption (pyridinoline and deoxypyridinoline) were assessed by HPLC. Six percent, 36 %, and 64 % of subjects had 25-hydroxyvitamin D concentrations < 25, < 50, and < 80 nmol/L throughout the year, respectively. 25-hydroxyvitamin D was significantly and inversely correlated with serum bone-specific alkaline phosphatase (r = 0.119; p = 0.022) and urinary pyridinoline (r = 0.207; p < 0.0001) and deoxypyridinoline (r = 0.230; p < 0.0001). Stratification on the basis of tertiles [T] of 25-hydroxyvitamin D (< 47.6 [T(1)]; 47.6 - 85.8 [T₂]; > 85.8 [T₃] nmol/L), showed that urinary pyridinoline and deoxypyridinoline were significantly lower in subjects in the 2(nd) and 3(rd) compared to the 1(st) tertile (p < 0.015). Low vitamin D status (< 50 nmol/L) was associated with an increased rate of bone turnover in this older pan-European cohort.

Eldecalcitol

Eldecalcitol (1α,25[OH](2)-2β-(3-hydroxypropyloxy)vitamin D(3); ED-71; Edirol®) is an orally administered analogue of active vitamin D (calcitriol) that is available in Japan for the treatment of osteoporosis. Two randomized, double-blind, multicentre trials were conducted in patients with osteoporosis. In a placebo-controlled, dose-ranging trial, eldecalcitol significantly reduced serum bone-specific alkaline phosphatase (BALP) and serum osteocalcin, markers of bone formation, more than placebo. Eldecalcitol at a 1.0 μg/day dosage, but not at lower dosages, also significantly reduced urinary type I collagen N-telopeptide (NTX), a marker of bone resorption, more than placebo. In a comparison with alfacalcidol (a prodrug of calcitriol), eldecalcitol produced significantly greater reductions in serum BALP and urinary NTX, and had a positive effect on CT markers of femoral biomechanical properties. In the comparison with alfacalcidol, eldecalcitol 0.75 μg/day significantly reduced the 3-year incidence of vertebral fractures, with an absolute risk reduction of 4.1% over this period, representing a relative risk reduction of 26%. There was no significant difference in the rate of non-vertebral fractures. In both trials, eldecalcitol treatment was also associated with an increase in bone mineral density, whereas patients who received the comparators generally had a reduction in bone mineral density. Increases in blood calcium (to >2.6 mmol/L) and urinary calcium (to >0.1 mmol/L glomerular filtrate) were the most clinically important treatment-emergent adverse events. In the placebo-controlled, dose-ranging trial, 23% and 25% of patients in the eldecalcitol 1 μg/day group had increased blood and urinary calcium compared with 7% and 7%, 6% [corrected] and 9%, and 0% and 1.9% in the eldecalcitol 0.5 and 0.75 μg/day, and placebo groups, respectively. In the comparison with alfacalcidol, 21.0% and 13.5% of eldecalcitol 0.75 μg/day and alfacalcidol 1.0 μg/day recipients had increased blood calcium, whereas hypercalcaemia (defined as a serum calcium >2.9 mmol/L) occurred in 0.4% and urolithiasis in 1.3% of eldecalcitol recipients over 36 months of treatment. Eldecalcitol is an efficacious treatment for patients with osteoporosis that should be further investigated in head-to-head trials with other recommended first-line pharmacological treatments.

Effect of zoledronic acid compared with raloxifene on bone turnover markers in postmenopausal women with low bone density

The aim of this study was to assess the effects of zoledronic acid and raloxifene on bone turnover markers. This multicenter, randomized, double-blind study involved 110 postmenopausal women with low bone mineral density who received either a single intravenous infusion of zoledronic acid 5 mg or 6 months of daily oral raloxifene 60 mg. The primary efficacy variable was change from baseline in the bone resorption marker urine N-telopeptide of type I collagen. The secondary efficacy variable was change from baseline in the bone formation marker serum bone-specific alkaline phosphatase. Analysis time points were at 2, 4, and 6 (primary) months. At 6 months, zoledronic acid produced a significantly greater reduction than did raloxifene in urine N-telopeptide of type I collagen (P < 0.001). Zoledronic acid also yielded significantly greater decreases in urine N-telopeptide of type I collagen at 2 and 4 months and in serum bone-specific alkaline phosphatase at all time points (P < 0.001 vs raloxifene for all comparisons). Both treatments were well tolerated. More adverse events occurred in the zoledronic acid group; these were primarily transient postdose symptoms that occurred within the first 3 days after the infusion. Zoledronic acid demonstrated significantly greater decreases in bone turnover markers than did raloxifene in postmenopausal women with low bone mass.

Association between the Healthy Eating Index and bone turnover markers in US postmenopausal women aged ≥45 y

Some studies have reported that overall diet quality affects bone status in postmenopausal women; however, the findings are inconsistent. Our primary objective was to examine the association between overall diet quality and bone turnover markers (BTMs) in postmenopausal women aged ≥45 y by using the Healthy Eating Index 2005 (HEI-2005)-a diet quality-assessment tool-developed by the US Department of Agriculture. Our secondary objective was to explore the associations between the components of the HEI-2005 and the MyPyramid food groups and BTMs. We used cross-sectional data from NHANES 1999-2002. Multiple regression models with adjustments for relevant confounders were used to examine the relation between the total HEI-2005 score and its components and food groups and serum bone-specific alkaline phosphatase (BAP), a biomarker of bone formation, and urinary N-telopeptides/creatinine (uNTx/Cr), a biomarker of bone resorption. No association was found between the total HEI-2005 score and BTMs. The milk group component of HEI-2005 had a significant negative linear relation with uNTx/Cr. Women in the lowest tertile of the MyPyramid milk group had the highest uNTx/Cr. Those in the highest tertile of energy-adjusted added sugar intake had the highest BAP. Our results support the ability of a healthy diet with adequate dairy intake to promote bone health in aging women. However, we found that the HEI-2005 is not a good measure of healthy eating for optimal bone health. Further research is needed to develop an overall dietary assessment tool in relation to bone health for postmenopausal women.

Evaluation of bone mineral density in Turkish children with severe haemophilia A: Ankara hospital experience

This study was conducted to understand the pathogenetic mechanisms that are involved in the development of bone loss in children with severe haemophilia A (HA). Fourty-four children with severe HA and 40 age- and gender-matched healthy control subjects were enrolled in this study. Markers of bone remodelling and osteoclast regulation including serum bone specific alkaline phosphatase, parathormone, 25-hydroxy-vitamin D(3) (25HOvitD(3)), osteocalcin and calcitonin levels were studied. Bone mineral density (BMD) was also studied in all children. The measurement of markers of bone remodelling and osteoclast regulation suggested increased osteoclast-mediated resorption activity in children with severe HA. Although serum parathormone levels were significantly increased, serum 25HOvitD(3) and osteocalcin levels were significantly reduced. BMD was significantly reduced in severe haemophilics compared with healthy controls. There was also significant inverse correlation between BMD z-score and total joint scores, and insignificant inverse correlation between BMD z-score and single joint scores. There were also significant inverse correlation between 25HOvitD(3) and osteocalcin levels and total joint scores. Children with severe HA could have significantly reduced BMD, compared with gender- and age-matched healthy control subjects. Our results of the markers of bone remodelling and osteoclast regulation suggested that increased osteoclast-mediated resorption and decreased osteoblastic activity in children with severe HA. All children with severe HA should be routinely screened in terms of BMD.

Diagnostic usefulness of bone mineral density and biochemical markers of bone turnover in predicting fracture in CKD stage 5D patients--a single-center cohort study

In chronic kidney disease stage 5D, diagnostic usefulness of bone mineral density (BMD) in predicting fracture has not been established because of variable results in previous studies. The reason for this may be the heterogeneity of underlying pathogenesis of the fracture. BMD was measured annually and serum biochemistry monthly for 485 hemodialyzed patients from April 2003 to March 2008, and all fractures were recorded. Forty-six new episodes of any type of fracture and 29 cases of prevalent spine fracture were recorded. Serum bone-specific alkaline phosphatase (b-AP) was a very useful surrogate marker for any type of incident fracture risk [area under curve (AUC) = 0.766, P < 0.0001]. A significantly greater risk of any type of incident fracture was associated with parathyroid hormone (PTH) levels either <150 pg/mL [hazard ratio (HR) = 3.47, P < 0.01] or >300 pg/mL (HR = 5.88, P < 0.0001) compared with 150-300 pg/mL. Receiver-operating characteristic analysis demonstrated a significant predictive power for incident of any type of fracture by BMD at the total hip (AUC = 0.760, P < 0.0001) and other hip regions in females in the lower PTH group (PTH < 204 pg/mL). BMDs at every site but whole body or lumbar spine had significant power to discriminate prevalent spine fracture regardless of gender or PTH. Hemodialyzed patients with low or high PTH or increased b-AP had a high fracture risk. BMD by Dual Energy X-ray Absorptiometry (DEXA), especially at the total hip region, was useful to predict any type of incident of fracture for females with low PTH or to discriminate prevalent spine fracture for every patient.

Effects of toremifene and anastrozole on serum lipids and bone metabolism in postmenopausal females with estrogen receptor–positive breast cancer: the results of a 2-year multicenter open randomized study

The potential long-term adverse effects on quality of life have to be considered when selecting agents for adjuvant hormonal treatment for postmenopausal patients with estrogen receptor-positive breast cancer. We performed a 2-year multicenter randomized study to assess the differences in the time course effects between toremifene (TOR) and anastrozole (ANA) on serum lipid profiles and bone metabolism. This study assessed the serum levels of triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), apolipoprotein A-1 (Apo A1), and apolipoprotein B (Apo B) as lipid profiles and bone-specific alkaline phosphatase (BAP) and the N-telopeptide of type-I collagen (NTX) as bone turnover markers in patients who received daily doses of 40 mg and 1 mg for TOR and ANA, respectively. A decreased serum level of TC, LDL-C, and Apo B was, respectively, observed at 6 months in 6.2, 12.9, and 13.8% of the patients who received TOR compared with the baseline. These decreases were maintained for at least 24 months. These lipid levels were not changed in those who received ANA. In the TOR patients, there was an increase in the serum level of HDL-C and Apo A1 at 6 months in 17.1 and 16.3%, respectively, which was maintained for at least 24 months, whereas these levels were almost stable in the patients who received ANA. Serum BAP decreased by 12.1% at 12 months and further decreased at 24 months and the serum NTX decreased by 22.0% at 6 months, which was maintained for at least 24 months in the patients who received TOR. In contrast, the serum BAP was increased by 26.0% at 6 months and by 29.2% at 12 months and the serum NTX increased by 21.3% at 24 months compared with baseline in those received ANA. However, the serum BAP increase was not significant at 24 months. TOR provides better effects than ANA in terms of lipid profiles and bone metabolism in postmenopausal females with early breast cancer.