Biomarkers for osteoporosis management: utility in diagnosis, fracture risk prediction and therapy monitoring

Effects of sodium dehydroacetate on broiler chicken bones

Sodium dehydroacetate (DHA-Na) is a fungicidal preservative widely used in food and animal feed. DHA-Na can induce coagulation disorders in rats and poultry by inhibiting carboxylation of vitamin K-dependent proteins; it can also impair bone development in zebrafish. However, the effects of DHA-Na on broiler chicken bones remain unknown. Here, we assessed whether DHA-Na impairs bone development in broiler chickens. We administered Suji yellow chickens with 200 to 800 mg/kg DHA-Na, 2 mg/kg vitamin K, or both for 2 mo. Bone metabolite-related serum indicators, tissue micromorphology, and relevant protein expression were monitored during the treatment period. We also assessed primary chicken osteoblast activity, differentiation, and bone metabolite-related proteins after treatment with DHA-Na, vitamin K, or both. The results demonstrated that DHA-Na reduced bone index values and serum and bone osteoblast differentiation marker levels but blocked bone vitamin K cycle. DHA-Na also increased serum osteoclast differentiation marker levels, as well as the bone ratio of receptor activator of nuclear factor kappa-Β ligand to osteoprotegerin ratio. Moreover, DHA-Na reduced bone trabecular number, thickness, and area and increased trabecular separation considerably. In general, compared with the control group, the DHA-Na group demonstrated impairments in osteoblast activity and differentiation, as well as in the vitamin K cycle. By contrast, vitamin K supplementation led to considerable attenuation of the DHA-Na-induced decrease in osteogenic marker levels, along with a considerable increase in serum bone absorption marker levels and restoration of DHA-Na-induced bone microstructure damage. Vitamin K also attenuated DHA-Na-induced impairment in osteoclasts. In conclusion, the results indicated that in broiler chickens, DHA-Na supplementation can damage bones by inhibiting osteoblast function and increasing osteoclast activity; this damage can be prevented through vitamin K supplementation.

Efficacy of lumbar and abdominal muscle rehabilitation training on degree of osteoporosis, pain and anxiety in elderly patients with osteoporotic vertebral compression fracture after PKP and compliance analysis

Purpose

To explore the rehabilitation effect and compliance of lumbar and abdominal muscle rehabilitation training in patients with osteoporotic vertebral compression fracture (OVCF) after percutaneous balloon vertebroplasty (PKP).

Methods

A total 177 elderly patients with OVCF were divided into rehabilitation group (n = 104) and control group (n = 73) according to whether they received psoas and abdominal muscle rehabilitation training for 3 months after PKP. The differences of general data, orthopaedic rehabilitation, prognosis and bone metabolism were compared between the two groups. All the patients were divided into compliance group (68 cases) and non-compliance group (36 cases) according to compliance. Orthopaedic rehabilitation indicators, prognostic indicators of PKP, and bone metabolism-related parameters were collected for analysis of Chi-square test and Logistic regression. ROC curve was used to analyze the predictive value of bone metabolism related indicators in the compliance of lumbar and abdominal muscle rehabilitation training.

Results

There was no significant difference in the general data between the rehabilitation training group and the control group (All p > 0.05). Compared with the control group, the Berg balance scale score was significantly increased, while the Visual Analogue Scale (VAS) score, Oswestry Disability Index (ODI) score and the proportion of new fractures were significantly decreased in the rehabilitation training group (All p < 0.05). Compared with the control group, the bone mineral density (BMD) T value, osteocalcin (OCN) and 25-hydroxyvitamin D (25 (OH) D) levels were significantly increased and the levels of type I N-propeptide (P1NP) and β-isomerized C-terminal telopeptides (β-CTX) were significantly decreased in the rehabilitation training group compared with the control group (All p < 0.05). Chi-square test and Logistic regression analysis showed that age > 75 years, severe anxiety, severe pain and postoperative complications were significantly associated with the compliance of psoas and abdominal muscle rehabilitation training in patients with OVCF after PKP. ROC curve analysis showed that BMD T value, OCN, P1NP, β-CTX, or 25-OH-D levels predicted the AUC of rehabilitation training compliance in patients with OVCF after PKP were 0.821, 0.835, 0.736, 0.715, and 0.748, respectively.

Conclusion

Rehabilitation training of lumbar and abdominal muscles can significantly improve the efficacy of PKP, reduce the degree of osteoporosis and improve the prognosis of patients with OVCF. Age, anxiety, pain and postoperative complications were independent risk factors affecting the compliance of psoas and abdominal rehabilitation training in patients with OVCF after PKP.

Albumin-to-alkaline phosphatase ratio may be a better predictor of survival than sclerostin, dickkopf-1, osteopontin, osteoprotegerin and osteocalcin

Objectives

The value of biochemical markers of bone turnover (BTMs) in predicting survival and disease remains unclear. In a prospective study we evaluated the novel biomarkers for bone turnover sclerostin, dickkopf-1 (DKK-1), osteopontin (OPN), osteoprotegerin (OPG) and osteocalcin (OC), as well as a traditional biomarker, alkaline phosphatase (ALP) in relation to risk of mortality, cardiovascular events and fractures.

Participants

and Methods:Routine blood tests and serum BTMs, including ALP, were analyzed in patients with hip fracture n = 97, stroke n = 71 and healthy volunteers n = 83 (mean age 86, 83 and 77, respectively), followed for 7 years. Hazard Ratios (HR) were calculated for mortality, cardiovascular events and fractures in relation to these biomarkers. After adding the albumin-to-ALP ratio (AAPR) a post hoc analysis was performed.

Results

120 participants died during the study. In the entire group of patients and volunteers (n = 251) higher AAPR (HR 0.28, 95 % CI 0.14-0.59, p < 0.001) was associated with decreased mortality. OPN and OPG were associated with mortality risk only in the univariate statistical analysis. HR for high AAPR in relation to new cardiovascular events was borderline significant (HR 0.29, 95 % CI 0.08-1.06, p = 0.061). None of the examined biomarkers were associated with new fractures, nor with an increased risk of a new cardiovascular event.

Conclusions

AAPR may be a better predictor of mortality than the more novel BTMs, and higher AAPR could be associated with longer life expectancy. Further studies should determine the clinical usefulness of AAPR as a biomarker of mortality and cardiovascular disease.

Osteoporosis: Investigations and Monitoring

Background

Osteoporosis is characterized by microarchitectural disruption of the bone, decrease in bone mineral density, and increased skeletal fragility and risk of fracture. Osteoporosis occurs due to the decoupling of bone formation and bone resorption, with a significant increase in resorption. This review article focuses on the role of laboratory investigations in the diagnosis and monitoring of treatment in patients with osteoporosis.

Methods

This review article collected literature from various databases using keywords such as 'Laboratory investigations', 'Osteoporosis', 'Diagnosis', 'Monitoring', and 'Bone turnover markers'.

Results and Discussion

Laboratory investigations, including serum calcium, alkaline phosphatase, vitamin D, and parathormone, are commonly performed tests to exclude secondary causes of osteoporosis and monitor the response to therapy. The biochemical markers of bone turnover are newly emerged tests for monitoring individual patients with osteoporosis. These markers are classified as bone formation and resorption markers, measurable in both serum and urine. The use of these markers is limited by biological and analytical variability. The International Federation of Clinical Chemistry and Laboratory Medicine and the International Osteoporosis Foundation recommend serum procollagen type 1 amino-terminal propeptide as the bone formation marker and β-form of C-terminal cross-linked telopeptide of type I collagen (β-CTx-1/β-CrossLaps) as the marker of choice, using standardized procedures. However, in specific cases, such as patients with chronic renal disease, CTx-1 is replaced by the resorption marker tartrate-resistant acid phosphatase 5b, as its levels are not affected by renal excretion.

Conclusion

Bone turnover markers have emerged as tools for the assessment of osteoporosis, using standardized procedures, and are useful in monitoring therapy and treatment compliance.

UBAP2 plays a role in bone homeostasis through the regulation of osteoblastogenesis and osteoclastogenesis

Osteoporosis is a condition characterized by decreased bone mineral density (BMD) and reduced bone strength, leading to an increased risk of fractures. Here, to identify novel risk variants for susceptibility to osteoporosis-related traits, an exome-wide association study is performed with 6,485 exonic single nucleotide polymorphisms (SNPs) in 2,666 women of two Korean study cohorts. The rs2781 SNP in UBAP2 gene is suggestively associated with osteoporosis and BMD with p-values of 6.1 × 10-7 (odds ratio = 1.72) and 1.1 × 10-7 in the case-control and quantitative analyzes, respectively. Knockdown of Ubap2 in mouse cells decreases osteoblastogenesis and increases osteoclastogenesis, and knockdown of ubap2 in zebrafish reveals abnormal bone formation. Ubap2 expression is associated with E-cadherin (Cdh1) and Fra1 (Fosl1) expression in the osteclastogenesis-induced monocytes. UBAP2 mRNA levels are significantly reduced in bone marrow, but increased in peripheral blood, from women with osteoporosis compared to controls. UBAP2 protein level is correlated with the blood plasma level of the representative osteoporosis biomarker osteocalcin. These results suggest that UBAP2 has a critical role in bone homeostasis through the regulation of bone remodeling.

Impact of Intravenous Iron Substitution on Serum Phosphate Levels and Bone Turnover Markers-An Open-Label Pilot Study

The association between intravenous iron substitution therapy and hypophosphatemia was previously reported in patients with iron deficiency anemia. However, the extent of hypophosphatemia is thought to depend on the type of iron supplementation. We hypothesized that the intravenous application of ferric carboxymaltose and iron sucrose leads to a different longitudinal adaptation in serum phosphate levels. In this open-label pilot study, a total of 20 patients with inflammatory bowel diseases or iron deficiency anemia were randomly assigned to one of two study groups (group 1: ferric carboxymaltose, n = 10; group 2: iron sucrose, n = 10). Serum values were controlled before iron substitution therapy, as well as 2, 4, and 12 weeks after the last drug administration. The primary objective of the study was the longitudinal evaluation of serum phosphate levels after iron substitution therapy with ferric carboxymaltose and iron sucrose. The secondary objective was the longitudinal investigation of calcium, 25-hydroxyvitamin D (25(OH)D), intact parathyroid hormone, procollagen type 1 amino-terminal propeptide (P1NP), beta-CrossLaps (CTX), hemoglobin (Hb), iron, ferritin, and transferrin saturation levels. Two weeks after drug administration, phosphate levels were significantly lower (p < 0.001) in group 1 and ferritin levels were significantly higher (p < 0.001) in group 1. Phosphate levels (0.8-1.45 mmol/L) were below the therapeutic threshold and ferritin levels (10-200 ng/mL for women and 30-300 ng/mL for men) were above the therapeutic threshold in group 1. P1NP (15-59 µg/L) and CTX (<0.57 ng/mL) levels were above the therapeutic threshold in group 2. Four weeks after drug administration, significant differences were still observed between both study groups for phosphate (p = 0.043) and ferritin (p = 0.0009). All serum values except for Hb were within the therapeutic thresholds. Twelve weeks after drug administration, no differences were observed in all serum values between both study groups. Hb values were within the therapeutic threshold in both study groups. Serum 25(OH)D levels did not differ between both study groups throughout the whole study period and remained within the therapeutic threshold.

Vernacular Taxonomy, Cultural and Ethnopharmacological Applications of Avian and Mammalian Species in the Vicinity of Ayubia National Park, Himalayan Region

Numerous investigations on plant ethnomedicinal applications have been conducted; however, knowledge about the medicinal use of wild animals is still limited. This present study is the second on the medicinal and cultural meaning of avian and mammalian species used by the population in the surrounding area of the Ayubia National Park, KPK, Pakistan. Interviews and meetings were compiled from the participants (N = 182) of the study area. The relative frequency of citation, fidelity level, relative popularity level, and rank order priority indices were applied to analyze the information. Overall, 137 species of wild avian and mammalian species were documented. Of these, 18 avian and 14 mammalian species were utilized to treat different diseases. The present research showed noteworthy ethno-ornithological and ethno-mammalogical knowledge of local people and their connection with fauna, which might be useful in the sustainable utilization of the biological diversity of the Ayubia National Park, Khyber Pakhtunkhwa. Furthermore, in vivo and/or in vitro examination of the pharmacological activities of species with the highest fidelity level (FL%) as well as frequency of mention (FM) might be important for investigations on faunal-based new drugs.

Composition and Properties of Saliva in Patients with Osteoporosis Taking Antiresorptive Drugs

The aim of this study was to examine how the composition and properties of saliva change in people with osteoporosis who have received antiresorptive (AR) treatment, compared to patients with osteoporosis who have not yet received this treatment.

METHODS

The study population consisted of 38 patients with osteoporosis using AR drugs (Group I) and 16 patients with osteoporosis who had never used AR drugs (Group II). The control group consisted of 32 people without osteoporosis. Laboratory tests included determination of pH and concentrations of Ca, PO₄, total protein, lactoferrin, lysozyme, sIgA, IgA, cortisol, neopterin, activity of amylase at rest, and stimulated saliva. The buffering capacity of stimulated saliva was also determined.

RESULTS

There were no statistically significant differences between the saliva of Group I and Group II. No statistically significant correlation was found between the amount of time using AR therapy (Group I) and the tested parameters of the saliva. Significant differences were found between Group I and the control group. The concentrations of PO₄, lysozyme, and cortisol were higher, while concentrations of Ca ions, sIgA, and neopterin were lower, in comparison to the control group. The significant differences between Group II and the control group were smaller, and they concerned only the concentrations of lysozyme, cortisol, and neopterin.

CONCLUSIONS

The saliva of people with osteoporosis subjected to AR therapy and those not subjected to AR therapy did not show statistically significant differences in terms of the examined parameters of the saliva. However, the saliva of patients with osteoporosis taking and not taking AR drugs was significantly different compared to the saliva of the control group.

miRNA-27a is essential for bone remodeling by modulating p62-mediated osteoclast signaling

The ability to simultaneously modulate a set of genes for lineage-specific development has made miRNA an ideal master regulator for organogenesis. However, most miRNA deletions do not exhibit obvious phenotypic defects possibly due to functional redundancy. miRNAs are known to regulate skeletal lineages as the loss of their maturation enzyme Dicer impairs bone remodeling processes. Therefore, it is important to identify specific miRNA essential for bone homeostasis. We report the loss of MIR27a causing severe osteoporosis in mice. MIR27a affects osteoclast-mediated bone resorption but not osteoblast-mediated bone formation during skeletal remodeling. Gene profiling and bioinformatics further identify the specific targets of MIR27a in osteoclast cells. MIR27a exerts its effects on osteoclast differentiation through modulation of Squstm1/p62 whose mutations have been linked to Paget's disease of bone. Our findings reveal a new MIR27a-p62 axis necessary and sufficient to mediate osteoclast differentiation and highlight a therapeutic implication for osteoporosis.

Effects of odanacatib on bone-turnover markers in osteoporotic postmenopausal women: a post hoc analysis of the LOFT study

This post hoc analysis and modeling study examined the mechanism of action of odanacatib using a statistical model to explain sCTx response in ODN-treated patients as a function of other bone-turnover biomarkers that, with other observed biomarker changes, showed that odanacatib persistently inhibited osteoclastic bone removal activity without preventing osteoclastogenesis.

INTRODUCTION

Odanacatib (ODN) is an oral selective cathepsin K (CatK) inhibitor, previously in development for osteoporosis treatment. A post hoc analysis examined ODN's mechanism of action on bone-turnover biomarkers.

METHODS

A subset of patients who completed 60 months' treatment in the Long-Term Odanacatib Fracture Trial (LOFT; NCT00529373) (N = 112 [57 ODN, 55 placebo]) were evaluated. Serum (s) and urine (u) samples were assayed at baseline and months 6-60 for 10 known bone-remodeling biomarkers: sCTx, uαα- and uββCTx/Cr, uNTx/Cr, sNTx, uDPD/Cr, sICTP, sTRAP5b, sPINP, and sBSAP. Because the CrossLaps® CTx assay identifies the CTx peptide as well as larger molecular weight CTx-containing peptides, including ICTP, a best-fit model was developed to explain the transient sCTx reduction in ODN-treated patients.

RESULTS

ODN persistently reduced the bone-resorption markers sNTx, uNTx/Cr, uαα- and uββCTx/Cr, and uDPD/Cr, and gradually increased the target-engagement marker sICTP and osteoclast number (sTRAP5b), versus placebo from baseline to month 60. sCTx was transiently reduced with ODN within 12 months, returning to baseline by month 48. Modeling suggested that sCTx changes in the ODN group were primarily due to increased accumulation of larger CTx species, including sICTP. The bone-formation markers sPINP and sBSAP showed partial reductions, versus placebo, in the first 6 months but approached baseline by months 48-60.

CONCLUSION

Observed changes in bone-turnover biomarkers support the persistent efficacy of ODN in direct inhibition of osteoclastic bone-resorption activity, without inhibition of osteoclastogenesis. Long-term evaluation also underscores the unique mechanism of ODN on osteoclastic collagen processing and subsequently osteoblastic bone formation.

TRIAL REGISTRATION

NCT00529373.

Orang Asli Health and Lifeways Project (OA HeLP): a cross-sectional cohort study protocol

INTRODUCTION

Non-communicable disease (NCD) risk is influenced by environmental factors that are highly variable worldwide, yet prior research has focused mainly on high-income countries where most people are exposed to relatively homogeneous and static environments. Understanding the scope and complexity of environmental influences on NCD risk around the globe requires more data from people living in diverse and changing environments. Our project will investigate the prevalence and environmental causes of NCDs among the indigenous peoples of Peninsular Malaysia, known collectively as the Orang Asli, who are currently undergoing varying degrees of lifestyle and sociocultural changes that are predicted to increase vulnerability to NCDs, particularly metabolic disorders and musculoskeletal degenerative diseases.

METHODS AND ANALYSIS

Biospecimen sampling and screening for a suite of NCDs (eg, cardiovascular disease, type II diabetes, osteoarthritis and osteoporosis), combined with detailed ethnographic work to assess key lifestyle and sociocultural variables (eg, diet, physical activity and wealth), will take place in Orang Asli communities spanning a gradient from remote, traditional villages to acculturated, market-integrated urban areas. Analyses will first test for relationships between environmental variables, NCD risk factors and NCD occurrence to investigate how environmental changes are affecting NCD susceptibility among the Orang Asli. Second, we will examine potential molecular and physiological mechanisms (eg, epigenetics and systemic inflammation) that mediate environmental effects on health. Third, we will identify intrinsic (eg, age and sex) and extrinsic (eg, early-life experiences) factors that predispose certain people to NCDs in the face of environmental change to better understand which Orang Asli are at greatest risk of NCDs.

ETHICS AND DISSEMINATION

Approval was obtained from multiple ethical review boards including the Malaysian Ministry of Health. This study follows established principles for ethical biomedical research among vulnerable indigenous communities, including fostering collaboration, building cultural competency, enhancing transparency, supporting capacity building and disseminating research findings.

Estradiol and zinc-doped nano hydroxyapatite as therapeutic agents in the prevention of osteoporosis; oxidative stress status, inflammation, bone turnover, bone mineral density, and histological alterations in ovariectomized rats

Osteoporosis (OP) is a serious health problem, and the most popular therapeutic strategy for OP is hormone replacement (estrogen); however, it increases the risk of reproductive cancers. Hydroxyapatite (HA) nanoparticles have a similar chemical structure to the bone mineral component and can be used as a new remedy for OP. This study was designed to investigate the osteoporosis-protective potential of nano zinc hydroxyapatite (ZnHA-NPs) and/or estradiol (E2) combined therapy. A total of 35 adult female rats were assigned into five groups (n = 7): 1) control group; 2) ovariectomized group (OVX); 3) OVX received oral estradiol replacement therapy (OVX/E2); 4) OVX received ZnHA replacement therapy (OVX/ZnHA); and 5) OVX received both estradiol and ZnHA-NPs combined therapy (OVX/E2+ZnHA). After 3 months of treatment, serum bone markers and estrogen level, oxidative/antioxidant, and inflammatory cytokines were determined. Additionally, femoral expression of estrogen receptors alpha and beta (ESR1; ESR2), receptor activator of nuclear factor-kappa B (RANKL) ligand, osteoprotegerin (OPG), bone mineral density (BMD), histological alterations, and immunohistochemical expression of vascular endothelial growth factor (VEGF) and proliferating cell nuclear antigen (PCNA) were assessed. ALP, PINP, Ca, and P concentrations improved significantly (p < 0.05) in all treatment groups, especially in the OVX/E + ZnHA group. MDA and NO were higher in OVX rats, while SOD activity and GSH were lower (p < 0.05). E2 alone or with ZnHA-NPs restored the estimated antioxidant molecules and cytokines toward normal levels in OVX rats (p < 0.05). On the other hand, E2 and ZnHA increased OPG and OC expression in femurs while decreasing ESR1, ESR2, and NF-kB expression (p < 0.05). The combination treatment was superior in the restoration of normal femoral histoarchitecture and both cortical and trabecular BMD (p < 0.05). Overall, the combined therapy of OVX/E2+ZnHA was more effective than the individual treatments in attenuating excessive bone turnover and preventing osteoporosis.

Changes in bone mineral density in unconscious immobile stroke patients from the acute to chronic phases of brain diseases

Objectives

Decreased bone mineral density (BMD) is observed in immobile stroke patients. But it is not clarified yet how rapidly BMD reduction occurs or what the most influencing factor to BMD loss is.

Methods

BMDs in the lumbar vertebrae and the proximal femur of the paralyzed side were measured in 100 immobile stroke patients at 1 week (0 month), 1 month, and 2 months after admission. The levels of serum calcium, phosphorous, 25-hydroxyvitamin D, and urine cross-linked N-telopeptide of type I collagen (NTx) were also measured.

Results

The average age of patients was 75.0 ± 11.4 years (31–94 years). No BMD reduction was identified in the lumbar vertebrae in 2 months; however, BMD in the femur significantly decreased in 2 months in female patients (P < 0.05). Serum calcium and phosphorous levels remained within the normal range during hospitalization, and 25-hydroxyvitamin D value rose in 2 months. Urine NTx significantly increased in both males and females in 2 months (male: P < 0.05, female: P < 0.01).

Conclusions

While there was no significant change in lumbar spine BMD in the 2 month period of immobilization after stroke, BMD in the proximal femur showed a significant reduction, particularly in women. The differential loss of BMD in the 2 regions of interest could possibly be due to the physical forces acting on different body parts during mobilization and nutritional factors. More studies are needed with larger study samples and prolonged follow-up to check the accuracy of these observations.

Effects of ultra-low dose hormone therapy on biochemical bone turnover markers in postmenopausal women: A randomized, placebo-controlled, double-blind trial

Objective

Evaluate the effects of ultra-low-dose hormone therapy (Ultra-LD HT) with 17β-estradiol 0.5 mg and norethisterone acetate 0.1 mg (E2 0.5/NETA 0.1) versus placebo on bone turnover markers (BTM) in postmenopausal women.

Study Design

A multicenter, double-blind, randomized, placebo-controlled study was performed with 107 participants who received one tablet daily of E2 0.5/NETA 0.1 or placebo for 24-weeks. Bone formation markers-N-terminal propeptide of type I procollagen (PINP) and Bone-specific alkaline phosphatase (BSAP), and bone resorption markers-C-telopeptide of type I collagen (CTX-I) and N-telopeptide crosslinked of type I collagen (NTX) were assessed before and at 12 and 24-weeks of treatment.

Results

Women treated with E2 0.5/NETA 0.1 had a significant reduction in the PINP marker from baseline (58.49 ± 21.12 μg/L) to week 12 (48.31 ± 20.99 μg/L) and week 24 (39.16 ± 16.50 μg/L). Placebo group, the PINP marker did not differ significantly. The analysis of the BSAP indicated a significant increase in the placebo group (13.8 ± 5.09 μg/L and 16.29 ± 4.3 μg/L, at baseline and week 24, respectively), whereas in the treatment group the values did not change. The analysis of the NTX marker showed a significant reduction only in the treatment group (43.21 ± 15.26 nM/mM and 33.89 ± 14.9 nM/mM, at baseline and week 24, respectively). CTX-I had a significant decrease in the treatment group from baseline (0.3 ± 0.16 ng/L) to week 12 (0.21 ± 0.14 ng/L) and week 24 (0.21 ± 0.12 ng/L).

Conclusion

Women receiving E2 0.5/NETA 0.1 experienced reductions in bone resorption and formation markers, an expected effect during the anti-resorptive therapy, suggesting a protective bone effect with the Ultra-LD HT.

Zoledronic Acid Ameliorates the Bone Turnover Activity and Periprosthetic Bone Preservation in Cementless Total Hip Arthroplasty

The administration of zoledronic acid (ZA) to patients who received cementless total hip arthroplasty (THA) has been reported to reduce bone turnover markers (BTMs) and increase bone mineral density (BMD). The effects of two-dose ZA versus placebo on cementless THA patients were analyzed in this five-year extension study. Alkaline phosphatase (ALP), osteocalcin (OC), procollagen 1 intact N-terminal propeptide (P1NP), serum calcium, renal function, radiological findings, and functional outcomes were compared in 49 patients, and the periprosthetic BMD of seven Gruen zones were compared in 19 patients. All the patients had normal renal function and calcium levels at their final follow-up. The mean ALP level in the ZA group was significantly lower at the fifth year, mean OC levels were significantly lower at the second and fifth year, and mean P1NP levels were significantly lower from 6 weeks to 5 years as compared with the control group. Fifth-year BMD levels were not found to be different between the ZA and control groups. The BMD Change Ratios in the ZA group were significantly increased in Gruen zone 6 at 1, 2, and 5 years. Our study results suggest that short-term ZA treatment with a subsequent 4-year drug holiday may inhibit serum BTMs and provide periprosthetic bone preservation at five years without adverse events.

Future modalities to assess fracture healing

Objectives:

Methods:

Results:

Conclusions:

Higher Levels of Circulating Osteoprogenitor Cells Are Associated With Higher Bone Mineral Density and Lean Mass in Older Adults: A Cross-Sectional Study

Circulating osteo progenitor (COP) cells are a heterogeneous population of cells that circulate within the peripheral blood with characteristics of the bone marrow mesenchymal stem and progenitor pool. Little is known about the behavior of this cell population in humans. The aim of this study was to identify whether a relationship exists between COP cells (as a percentage of the peripheral blood monocytic cells) and musculoskeletal morphometry and to identify if COP have potential clinical utility as a biomarker for osteoporosis. We recruited 57 older adults (median age: 69 years; IQR: 65, 75 years) living independently in the community and performed cross‐sectional analysis to identify associations between the percentage of COP cells and body composition parameters, and through receiver operating characteristic analysis, we evaluated their ability to act as a biomarker of osteoporosis. COP cells were moderately associated with whole‐body bone mineral density (BMD) (r = 0.323, p = 0.014) and bone mineral content (BMC) (r = 0.387, p = 0.003), neck of femur BMD (r = 0.473, p < 0.001), and BMC (r = 0.461, p < 0.001) as well as appendicular lean mass (ALM) (p = 0.038) and male sex (p = 0.044) in univariable analysis. In multivariable analysis controlling for age, gender, height, and weight, COP cells remained strongly associated with neck of femur BMD (p = 0.001) and content (p = 0.003). COP cells were also a good predictor of osteoporosis (dual‐energy X‐ray absorptiometry [DXA] T‐score < −2.5) at the neck of femur (cutoff: 0.4%; sensitivity: 100%; specificity 79%) and total body (cutoff: 0.35%; sensitivity: 80%; specificity: 81%). This study shows strong relationships between bone parameters and COP cell number and male sex. They also have potential as a biomarker of osteoporosis, which may provide a new tool for advanced detection and screening in clinical settings. Future larger evaluation studies should verify the cutoffs for biomarker use, and further explore the relationship between COP cells and muscle. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

The Efficacy and Safety of Chinese Herbal Medicine Xianling Gubao Capsule Combined With Alendronate in the Treatment of Primary Osteoporosis: A Systematic Review and Meta-Analysis of 20 Randomized Controlled Trials

Objective: Herein, we purposed to evaluate the efficacy along with the safety of Xianling Gubao capsule (XLGB) combined with alendronate (ALE) for primary osteoporosis (POP) from the current literature.

Materials and Methods: We carried out a search for electronic literature in the PubMed, Chinese National Knowledge Infrastructure, EMBASE, Wanfang Web of Science, Chinese Biomedical Literature Database, Cochrane Library, as well as Chinese VIP databases targeting articles published from inception to December 2020. Only randomized controlled trials (RCTs) were enrolled into the study. Alkaline phosphatase (ALP), visual analogue scale (VAS), serum phosphorus (S-P), bone gla protein (BGP), serum calcium (S-Ca) and bone mineral density (BMD) were the primary outcome variable. The total clinical effective rate along with the adverse drug reaction (ADR) were the secondary outcome variables. The meta-analysis was conducted using RevMan 5.3 and STATA 12.0. GRADE pro3.6.1 software was used for the assessment of evidence quality.

Results: Overall, 20 RCTs focusing on 1911 patients were enrolled into the study. Our meta-analysis demonstrated that XLGB combined with ALE remarkably increased BMD (p < 0.001), BGP (p < 0.001), S-Ca (p < 0.001), S-P (p < 0.001) and effective rate (p < 0.001) than ALE alone in patients with POP. Moreover, ALP (p < 0.001) and VAS (p < 0.001) were overtly by decreased XLGB. However, XLGB combined with ALE would not markedly increase the rate of ADR in contrast with ALE alone (p = 0.499).

Conclusion: The results of our study demonstrated that XLGB is a potential candidate for OP treatment. We recommend that rigorous, as well as high-quality trials involving large samples sizes should be conducted to confirm our findings.

Sex-related differences in bone metabolism in osteoporosis observational study

Although the incidence is lower in men than women, osteoporosis remains a significant health issue in men as it may give rise to severe complications if not managed appropriately. As men and women show different biological and social backgrounds, we retrospectively evaluated the differences in the bone metabolism between men and women using bone biomarkers.Bone mineral density (BMD) was determined in all patients using dual-energy X-ray absorptiometry (DXA) and analyzing various bone biomarkers such as carboxyl-terminal collagen crosslinks (CTX), osteocalcin (OCT), and alkaline phosphatase (ALP). The CTX/OCT ratio was used to estimate the association between bone absorption and formation.OCT, CTX, and ALP levels were elevated in patients with osteoporosis. Women displayed a higher incidence of osteoporosis and greater reduction in BMD than men. The mean OCT level in men was lower than that in women. Moreover, men showed significantly lower OCT levels than women of aged 65 and under 80 years old. Among patients with osteoporosis, men had a higher ratio of bone markers than women.Levels of biomarkers of bone formation and absorption were increased in the osteoporosis group. However, men showed lower increases in bone formation biomarkers than did women, indicating that the rate of bone formation relative to bone absorption did not increase in men compared with that in women. Therefore, we suggest that men and women have different bone metabolism in old age.

Effects of Teriparatide versus Salmon Calcitonin Therapy for the Treatment of Osteoporosis in Asia: A Meta-analysis of Randomized Controlled Trials

Objective:

The objective of this meta-analysis was to compare the efficacy and safety of teriparatide versus salmon calcitonin for the treatment of osteoporosis in Asian patients and to investigate whether the results of global studies could be applicable to Asian patients.

Methods:

PubMed, OVID, Cochrane Central Register of Controlled Trials (CENTRAL) and EMBASE up to December 2018 were searched. Eligible randomized controlled trials (RCTs) that compared teriparatide versus salmon calcitonin in Asian osteoporosis population were included. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used for data synthesis, and Cochrane Collaboration software Review Manager 5.3 was used to analyze the pooled data.

Results:

Three RCTs involving 529 patients were included (mean age 68.7 yr; 93.4% females; mean follow-up 6 months); outcome measures included bone mineral density (BMD) of the femoral neck, total hip and lumbar spine; bone markers and adverse events. We found that the period of 6-months of teriparatide treatment was helpful for the improvement of the BMD of lumbar vertebra, however, the improvement of BMD was not significant in the femoral neck and total hip joint. There was a positive correlation between bone-specific alkaline phosphatase (BSAP) and osteocalcin (OCN) and the response of Asian patients to subcutaneous injection of 20 micrograms per day of teriparatide. The proportion of the occurrence of adverse effects was more obvious in the teriparatide group compared with salmon calcitonin, but there was no significant difference.

Conclusion:

Results suggested that the use of teriparatide could improve the lumbar BMD by shortterm (six months) application in Asian osteoporosis patients, which is beneficial to the patients who cannot tolerate adverse events of long-term treatment. The BSAP and OCN bone markers could be useful to monitor the responses of Asian osteoporosis patients to teriparatide treatment. Finally, both of teriparatide and salmon calcitonin were well tolerated by Asian patients.

Change in Circulating Undercarboxylated Osteocalcin (ucOCN) Is Associated With Fat Accumulation in HIV-Seropositive Women

BACKGROUND

Bone mineral density loss and fat accumulation are common in people living with HIV. The bone-derived hormone, undercarboxylated osteocalcin (ucOCN) regulates fat metabolism. We investigated the relationship between ucOCN change and body fat change among perimenopausal/postmenopausal HIV-seronegative and HIV-seropositive women on long-term antiretrovirals.

METHODS

Perimenopausal and postmenopausal women enrolled in the Women's Interagency HIV Study MSK substudy underwent trunk and total fat assessment by dual energy x-ray absorptiometry (DXA) at study enrollment (index visit) and again 2 years later. Circulating ucOCN and cOCN were also measured at the index and 2-year visits. The correlation between the 2-year change in ucOCN and cOCN and change in trunk and total fat was assessed as a function of HIV serostatus using linear regression modeling. Multivariate linear regression assessed the association between ucOCN and cOCN change and total and trunk fat change after adjusting for sociodemographic variables. Linear regression models restricted to HIV-seropositive women were performed to examine the contributions of HIV-specific factors (index CD4 count, viral load, and combined antiretroviral therapy use) on the associations.

RESULTS

Increased ucOCN over the 2-year follow-up was associated with less trunk and total fat accumulation in models adjusting for HIV serostatus and participants sociodemographics, whereas there was no association with cOCN and the fat parameters. None of the HIV-specific factors evaluated influenced the association between ucOCN and fat parameters.

CONCLUSION

The current study suggests that increases in ucOCN are associated with decreased fat accumulation in HIV-seronegative and HIV-seropositive postmenopausal women on long-term antiretroviral therapy.

Polygonatum cyrtonema Hua polysaccharide exhibits anti-fatigue activity via regulating osteocalcin signaling

In the present study, we explored the anti-fatigue activity and its potential mechanism of a purified Polygonatum cyrtonema polysaccharide (PCP) on mice using weight-loaded swimming test. Results showed that PCP remarkably prolonged the exhaustive swimming time of mice when compared with normal control group. Meanwhile, PCP decreased serum levels of lactic acid (LA), blood uric nitrogen (BUN), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA), and increased the contents of liver glycogen, muscle glycogen and muscle ATP. These results revealed that PCP had good anti-fatigue ability. The histomorphologic analysis showed that PCP increased the cross-section area of the muscle fibers. Furthermore, PCP significantly enhanced the protein levels of bone morphogenetic protein-2 (BMP-2), phosphor-Smad1, Runt-related transcription factor 2 (Runx2) and osteocalcin (OC) in skeleton. Similar variation was also observed in the expression of osteocalcin signaling mediators of phosphorylated cAMP-response element binding protein (p-CREB) and phosphorylated hormone-sensitive lipase (p-HSL) in skeletal muscle. These results suggested that PCP resisted fatigue possibly via regulating osteocalcin signaling.

The Impact of Bone Mineral Density on Bone Metabolism and the Fracture Healing Process in Elderly Chinese Patients With Osteoporotic Vertebral Compression Fractures

BACKGROUND

The aim of this study was to investigate the effect of bone mineral density (BMD) on bone histomorphological parameters and bone turnover markers (BTMs) following osteoporotic vertebral compression fracture (OVCF) and to determine the correlation between BMD and the percentage of middle height compression during the healing process.

METHODS

A total of 206 patients with OVCFs were included in this study. Bone biopsy specimens were acquired during surgery. Blood samples were obtained to determine the serum concentrations of BTMs. The patients were divided into 2 groups according to BMD.

RESULTS

The concentrations of N-terminal propeptide of type I collagen (PINP) in the T-score ≤ -2.5 group (50.92 ± 12.78 ng/ml) were significantly lower than those in the T-score > -2.5 group (68.75 ± 28.66 ng/ml, p = 0.025) 3-6 mo after fracture. Moreover, the volume of necrotic bone in the T-score ≤ -2.5 group (15.15 ± 5.44%) was higher than that (1.67 ± 0.79%, p < 0.001) in the T-score > -2.5 group during the same period. BMD was statistically correlated with cancellous bone content (R_S = 0.761, p <0.001), PMHC (R_S = 0.85, p < 0.001), fibrous tissue volume (R_S = -0.376, p < 0.001), and necrotic bone content (R_S = -0.487, p < 0.001).

CONCLUSIONS

The healing process of OVCFs in the setting of low bone mass frequently occurs in the presence of decreased bone formation abilities, severe vertebral body height loss and a large amount of necrotic bone.

The carboxylation status of osteocalcin has important consequences for its structure and dynamics

BACKGROUND

The carboxylation status of Osteocalcin (Ocn) not only influences formation and structure in bones but also has important endocrine functions affecting energy metabolism and expenditure. In this study, the role of γ-carboxylation of the glutamate residues in the structure-dynamics-function relationship in Ocn is investigated.

METHODS

Three forms of Ocn, differentially carboxylated at the Glu-17, 21 and 24 residues, along with a mutated form of Ocn carrying Glu/Ala mutations, are modeled and simulated using molecular dynamics (MD) simulation in the presence of calcium ions.

RESULTS

Characterization of the global conformational dynamics of Ocn, described in terms of the orientational variations within its 3-helical domain, highlights large structural variations in the non-carboxylated osteocalcin (nOcn). The bi-carboxylated Ocn (bOcn) and tri-carboxylated (tOcn) species, in contrast, display relatively rigid tertiary structures, with the dynamics of most regions strongly correlated. Radial distribution functions calculated for both bOcn and tOcn show long-range ordering of the calcium ion distribution around the carboxylated glutamate (γGlu) residues, likely playing an important role in promoting stability of these Ocns. Additionally, the same calcium ions are observed to coordinate with neighboring γGlu, better shielding their negative charges and in turn stabilizing these systems more than do the singly coordinating calcium ions observed in the case of nOcn. bOcn is also found to exhibit a more helical C-terminal structure, that has been shown to activate its cellular receptor GPRC6A, highlighting the allosteric role of Ocn carboxylation in modulating the stability and binding potential of the active C-terminal.

CONCLUSIONS

The carboxylation status of Ocn as well and its calcium coordination appear to have a direct influence on Ocn structure and dynamics, possibly leading to the known differences in Ocn biological function.

GENERAL SIGNIFICANCE

Modification of Ocn sequence or its carboxylation state may provide the blueprint for developing high-affinity peptides targeting its cellular receptor GPRC6A, with therapeutic potential for treatment of metabolic disorders.

A phase 1 pooled PK/PD analysis of bone resorption biomarkers for odanacatib, a Cathepsin K inhibitor

To develop a framework for evaluating the resorption effects of Cathepsin K (CatK) inhibitors and to inform dose regimen selection, a pharmacokinetic/pharmacodynamic (PK/PD) model for odanacatib (ODN) was developed based upon data from Phase 1 studies. Pooled PK/PD data from 11 studies (N = 249) were fit reasonably to a population inhibitory sigmoid E_max model. Body weight on E₀ (baseline uNTx/Cr, urinary N-terminal telopeptide normalized by creatinine) and age on E_max (fractional inhibition of the biomarker response) were significant covariates for biomarker response. Simulations of typical osteoporosis patients (by age, sex and weight) indicated minimal differences between sexes in concentration-uNTx/Cr relationship. There was no evidence that regimen (daily vs. weekly dosing) influenced the PK/PD relationship of resorption inhibition for odanacatib. PK/PD models based on data from odanacatib (ODN) Phase 1 studies demonstrated that uNTx/Cr was an appropriate bone resorption biomarker for assessment of the effects of a CatK inhibitor. The models also identified the determinants of response in the PK/PD relationship for ODN (body weight on E₀ and age on E_max).

Associations between the serum levels of selected bone turnover markers and biological traits in nursing home women aged 80+ without inflammation. A pilot study

BACKGROUND

Bone turnover markers (BTM) reflect the status of bone remodeling processes responsible for bone mineral density. The existing body of evidence that osseous tissue can interact with many other body tissues and organs suggests that the cross-talks can lead to different relationships. The biological traits associated with BTMs have not been thoroughly studied in the elderly despite bone turnover being known to increase with age.

OBJECTIVE

To determine whether the C-terminal crosslinking telopeptides of type I collagen (CTXI) and the serum levels of total (TAP) and bone-specific (BAP) alkaline phosphatase are associated with the biological traits in nursing home women aged 80-92 years without inflammation and, if so, to indicate the best predictors of these BTM's blood concentrations.

METHODS

A group of 64 female volunteers aged 80 years and older, the residents of nursing homes, were screened for the study. Fifty two women were ineligible as they met the exclusion criteria. As a result, the study group consisted of 12 participants (85.1 ± 3.9 years; 58.1 ± 8.7 kg; 1.52 ± 0.06 m), all having blood C-reactive protein (CRP) levels below 3 mg/l. Also assessed were the participants' morphology, glucose and insulin levels, lipid profiles, CTXI, TAP, and BAP. Other measured parameters included body composition, resting heart rate and arterial blood pressure, isometric knee extension peak torque (IKEPT), and walking capacity (6-min walk test). The statistical analysis was performed using Pearson's correlation coefficients, the Benjamini-Hochberg procedure, and a stepwise multiple regression analysis with backward elimination.

RESULTS

Inverse correlations were found between CTX-I and hemoglobin concentration (HGB) (r = -0.680; p = .015), red blood cells count (RBC) (r = -0.664; p = .019), fat-free mass (r = -0.633; p = .027), body weight (r = -0.589; p = .044), and total cholesterol (r = -0.581; p = .048). The multiple regression analysis of CTX-I showed that body weight was the only independent variable that was statistically significant (r2 = 0.346; p < .05; SEE = 0.347 ng/ml). BAP was positively correlated with double product (DP) (r = 0.742; p = .006), RBC (r = 0.650; p = .022), HGB (r = 0.637; p = .026), mean arterial pressure (MAP) (r = 0.622; p = .031), diastolic blood pressure (DBP) (r = 0.612; p = .034), body height (r = 0.603; p = .038), IKEPT (r = 0.565; p = .056), and systolic blood pressure (SBP) (r = 0.538; p = .071). BAP, a dependent variable, was the most closely correlated with DP (r² = 0.550; p < .01; SEE = 9.161 U/l). TAP was also significantly associated with DP (r = 0.775; p = .003), with the association being stronger than between BAP and DP (r² = 0.600; p < .01; SEE = 1000.5 beats/min*mm Hg).

CONCLUSIONS

In relatively healthy the oldest-old nursing home women without inflammation, total body weight was the best predictor of bone resorption shown by the CTX-I concentration, whereas the rate pressure product (DP) turned out to best predict osteoblastic activity determinable from serum alkaline phosphatase activity. The results of the study suggest that the activity of serum TAP and BAP can be enhanced by different mechanisms.

Evaluating Bone Loss with Bone Turnover Markers Following Acute Spinal Cord Injury

STUDY DESIGN

Prospective observational study.

PURPOSE

To evaluate bone turnover markers (BTMs) in individuals with acute spinal cord injury (SCI) and to compare the results with those of healthy controls and postmenopausal females.

OVERVIEW OF LITERATURE

SCI significantly impacts bone health. Change in bone mineral density appears 6 months after SCI and rapid bone loss during the acute phase is often underestimated, resulting in osteoporosis and a high risk of sublesional fractures. However, few studies have evaluated BTMs in the Indian SCI population. Despite a high risk of fracture, there are no guidelines for the diagnosis, monitoring, and management of SCI-induced osteoporosis.

METHODS

Twenty patients within 1 month of traumatic SCI who had been admitted to a tertiary care rehabilitation center were included in this study. Serum BTMs, C telopeptide (CTX) as a bone resorption marker, and osteocalcin as a bone formation marker, were serially measured at baseline, and 3 and 6 months after SCI. BTMs of SCI patients were compared with those of a control group of age-matched healthy males, premenopausal females, and a vulnerable group of postmenopausal females.

RESULTS

BTMs were significantly elevated in patients with SCI, with maximum levels observed at the 3rd month of injury. At baseline, the bone resorption marker CTX was approximately 3 times higher in SCI patients than in the control male population and premenopausal females, and about double that of postmenopausal females. The rise in the bone formation marker was marginal in comparison to that of the bone resorption marker. BTMs were persistently elevated and did not reach the normative range until the 6th month of SCI.

CONCLUSIONS

Raised bone resorption markers in comparison to bone formation markers indicate hyper-resorption-related bone loss following acute SCI. Markedly elevated bone resorption markers in the SCI population, compared with those in control and vulnerable groups, emphasize the need for early bone health monitoring and management.

Effect of whole soy and isoflavones daidzein on bone turnover and inflammatory markers: a 6-month double-blind, randomized controlled trial in Chinese postmenopausal women who are equol producers

BACKGROUND

Human studies have demonstrated the beneficial effects of soy or isoflavones on bone metabolism. However, conflicting data remain. Equol is the intestinal metabolite of the isoflavone daidzein. The health benefits of soy are more pronounced in equol producers than those not producing equol. This 6-month randomized controlled trial aimed to examine the effect of whole soy (soy flour) and purified daidzein on bone turnover markers (BTMs) in Chinese postmenopausal women who are equol producers.

METHODS

A total of 270 eligible women were randomized to either one of the three isocaloric supplements as follows: 40 g soy flour (whole soy group), 40 g low-fat milk powder + 63 mg daidzein (daidzein group), or 40 g low-fat milk powder (placebo group) given as a solid beverage daily for 6 months. The following fasting venous samples were collected at the baseline and end of the trial to analyze BTMs: serum cross-linked C-telopeptides of type I collagen, bone-specific alkaline phosphatase, osteocalcin, procollagen type I N-terminal propeptide, and 25(OH)D₃. Inflammation-related biomarkers, such as serum interleukin-6, tumor necrosis factor-alpha, C-reactive protein, transferrin, and homocysteine, were also tested to explore potential mechanisms.

RESULTS

A total of 253 subjects validly completed the study protocol. Urinary isoflavones suggested a good compliance to the treatments. Intention-to-treat and per-protocol analyses indicated no significant difference in the 6-month or percentage changes in the parameters of bone metabolism and inflammatory markers among the three treatment groups.

CONCLUSIONS

Whole soy and purified daidzein at provided dosages exhibited no significant effect on the bone metabolism and inflammation levels among Chinese equol-producing postmenopausal women.

TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT01270737.

FGF-induced LHX9 regulates the progression and metastasis of osteosarcoma via FRS2/TGF-β/β-catenin pathway

Background

Fibroblast growth factor (FGF) and tumor growth factor-β (TGFβ) have emerged as pivotal regulators during the progression of osteosarcoma (OS). LHX9 is one crucial transcription factor controlled by FGF, however, its function in OS has not been investigated yet.

Methods

The expression of LHX9, FRS2, BMP4, TGF-beta R1, SMAD2, beta-catenin and metastasis-related proteins was measured by real-time quantitative PCR (RT-qPCR) and Western blot. CCK-8 assay and colony formation assay were employed to determine the proliferation of OS cells, while scratch wound healing assay and transwell assay were used to evaluate their migration and invasion, respectively. In vivo tumor growth and metastasis were determined by subcutaneous or intravenous injection of OS cells into nude mice.

Results

LHX9 expression was evidently up-regulated in OS tumor tissues and cell lines. Knockdown of LHX9 impaired the proliferation, migration, invasion and metastasis of OS cells. Mechanistically, LHX9 silencing led to the down-regulation of BMP-4, β-catenin and metastasis-related proteins, which was also observed in beta-catenin knockdown OS cells. By contrast, FRS2 knockdown conduced to the up-regulation of LHX9, BMP4, β-catenin and TGF-βR1, while TGF-beta inhibition repressed the expression of LHX9 and metastasis-related proteins. Additionally, let-7c modulates LHX9 and metastasis-related proteins by suppressing TGF-beta R1 expression on transcriptional level.

Conclusions

This study revealed LHX9 was essential for the proliferation, migration, invasion, and metastasis of OS cells via FGF and TGF-β/β-catenin signaling pathways.

Impacts of lead exposure and chelation therapy on bone metabolism during different developmental stages of rats

OBJECTIVE

To explore the impacts of Pb exposure and the dimercaptosuccinic acid (DMSA) chelation therapy on bone metabolisms in young rats of different ages, as well as the potential mechanisms.

METHOD

Young rats were exposed to 0.05%-0.1% Pb acetate for 19 days, during infanthood (postnatal day, PND2-20), childhood (PND21-39) and adolescenthood (PND40-58) respectively. In each developmental stage, rats were further divided into three subgroups: lead-exposed, one-course and two-course DMSA chelation therapy subgroups. Blood/bone lead concentrations, serum calciotropic hormones concentrations, and mRNA and protein expressions of bone turnover markers in the serum and bones were measured. Bone microstructures were analyzed using Micro-CT.

RESULTS

Compared with lead-exposed during childhood and adolescenthood, increases in blood/bone lead levels, and the changes of blood/bone lead and trabecular bone microstructures after one-course DMSA chelation were most significant in rats lead-exposed during infanthood (P < .05). The serum osteocalcin (OC) concentrations, mRNA/protein expressions of OC and runt-related transcription factor 2 (RUNX2) in bones all decreased after Pb exposure, along with significant increases in serum C-terminal telopeptide of type I collagen (CTX) concentrations (P < .05). These effects were accompanied by changes of serum parathormone (PTH) and 1,25-dihydroxyvitamin D₃ (1,25-(OH₂)-D₃) concentrations. DMSA chelation partially reversed the changes of bone microarchitectures, bone formation and resorption markers, and calciotropic-hormones, and the efficiency was greatest when the therapy was provided during infanthood.

CONCLUSION

Developmental Pb exposure impaired bone microstructures and interfered bone metabolism, and the exposure effect was more obvious during infanthood than during childhood and adolescenthood. Lead effects were partially reversed by chelation therapy, and the efficacy may be most significant when the therapy was provided at younger ages.

Radiographic Emphysema, Circulating Bone Biomarkers, and Progressive Bone Mineral Density Loss in Smokers

RATIONALE

Osteoporosis is common in individuals with chronic obstructive pulmonary disease. Lung-specific factors, including radiographic emphysema, independently associate with low bone mineral density in cross-sectional smoking cohorts. However, factors associated with progressive bone loss in smokers are understudied and largely unknown.

OBJECTIVES

To determine the relationship between radiographic emphysema, circulating bone metabolism markers, and pulmonary function and accelerated bone mineral density loss in smokers.

METHODS

Two hundred and forty male and female current and former smokers, 40 years of age or older, underwent baseline and 2-year assessments of pulmonary function, computed tomography-assessed emphysema, dual X-ray absorptiometry-measured bone mineral density, and circulating bone metabolism biomarker levels (type I collagen C-telopeptide [CTX], amino-terminal propeptide of type I procollagen [P1NP]). The association of radiographic emphysema, bone metabolism biomarker levels, and pulmonary function with accelerated hip bone mineral density loss, defined by the 75th percentile of annual hip bone mineral density decline, was determined by logistic regression modeling with adjustment for age, sex, inhaled and intermittent steroid use, active smoking, body mass index, and the presence of baseline low hip bone mineral density.

RESULTS

Of those participants with accelerated hip bone mineral density loss, 22% had moderate or severe visually assessed emphysema compared with 7.2% of smokers without accelerated bone mineral density decline. Moderate to severe visually assessed emphysema (odds ratio, 2.84; 95% confidence interval, 1.01-7.98 compared with trace/mild or no visually assessed emphysema) and the 75th percentile of CTX levels (odds ratio, 2.38; 95% confidence interval, 1.20-4.72 compared with CTX levels below the 75th percentile), a marker of bone resorption, were associated with accelerated hip bone mineral density decline after adjustment for covariates and the presence of baseline low hip bone mineral density. FEV₁% predicted was not associated with accelerated bone mineral density decline after adjustment for covariates. Multivariate modeling showed moderate to severe visually assessed emphysema, and the 75th percentiles of CTX were independently associated with accelerated hip bone mineral density decline after adjustment for covariates.

CONCLUSIONS

Emphysema and elevated markers of bone resorption are independently associated with progressive bone mineral density loss in smokers. These clinical markers may guide targeted bone mineral density screening and monitoring in smokers at highest risk.

Safety of bazedoxifene in Korean women with post-menopausal osteoporosis: a post-marketing surveillance study (PMSS)

Objectives: Bazedoxifene was found to be effective and well tolerated for the treatment and prevention of osteoporosis in postmenopausal women. This post-marketing surveillance study (PMSS) examined the safety of bazedoxifene in postmenopausal Korean women with osteoporosis, in a real-world setting. Methods: This PMSS was conducted from 2013 to 2017. A total of 3,423 subjects from 68 centers were enrolled and monitored for about 3 months (± 2 weeks). Bazedoxifene was prescribed at a dose of 20 mg/day. The safety of bazedoxifene was evaluated based on the number and nature of adverse events (AEs), serious AEs (SAEs), adverse drug reactions (ADRs) and serious ADRs (SADRs) in routine medical practice. Results: The mean age of study subjects was 69.51 years. The incidence of AEs and ADRs was 6.11% and 3.86%, respectively, and significantly decreased with increasing age (p= 0.0007). AE and ADR rates with bazedoxifene treatment of 3 months or more were significantly lower than those of less than 3 months (AE, 3.64% vs 30.00%, p < 0.0001; ADR, 1.74% vs 24.38%, p < 0.0001). Conclusion: In this study, bazedoxifene was well tolerated in the management of postmenopausal osteoporosis in Korean women, including those aged 70 years or more.

Clinical and translational pharmacology of the cathepsin K inhibitor odanacatib studied for osteoporosis

Cathepsin K (CatK) is a cysteine protease abundantly expressed by osteoclasts and localized in the lysosomes and resorption lacunae of these cells. CatK is the principal enzyme responsible for the degradation of bone collagen. Odanacatib is a selective, reversible inhibitor of CatK at subnanomolar potency. The pharmacokinetics of odanacatib have been extensively studied and are similar in young healthy men, postmenopausal women and elderly men, and were qualitatively similar throughout Phase 1 development and in-patient studies. Following 3 weeks of 50 mg once weekly dosing the geometric mean area under the curve from 0 to 168 hours was 41.1 μM h, the concentration at 168 hours was 126 nM and the harmonic mean apparent terminal half-life was 84.8 hr. Odanacatib exposure increased in a less than dose proportional manner due to solubility limited absorption. It is estimated that approximately 70% of the absorbed dose of odanacatib is eliminated via metabolism, 20% is excreted as unchanged drug in the bile or faeces, and 10% is excreted as unchanged drug in the urine. The systemic clearance was low (approximately 13 mL/min). Odanacatib decreases the degradation of bone matrix proteins and reduces the efficiency of bone resorption with target engagement confirmed by a robust decrease in serum C-telopeptides of type 1 collagen (approximately 60%), urinary aminoterminal crosslinked telopeptides of type 1 collagen to creatinine ratio (approximately 50%) and total urine deoxypyridinoline/Cr (approximately 30%), with an increase in serum cross-linked carboxy-terminal telopeptide of type 1 collagen (approximately 55%). The 50-mg weekly dosing regimen evaluated in Phase 3 achieved near maximal reduction in bone resorption throughout the treatment period. The extensive clinical programme for odanacatib, together with more limited clinical experience with other CatK inhibitors (balicatib and ONO-5334), provides important insights into the clinical pharmacology of CatK inhibition and the potential role of CatK in bone turnover and mineral homeostasis. Key findings include the ability of this mechanism to: (i) provide sustained reductions in resorption markers, increases in bone mineral density, and demonstrated fracture risk reduction; (ii) be associated with relative formation-sparing effects such that sustained resorption reduction is achieved without accompanying meaningful reductions in bone formation; and (iii) lead to increases in osteoclast number as well as other osteoclast activity (including build-up of CatK enzyme), which may yield transient increases in resorption following treatment discontinuation and the potential for nonmonotonic responses at subtherapeutic doses.

TZAP plays an inhibitory role in the self-renewal of porcine mesenchymal stromal cells and is implicated the regulation of premature senescence via the p53 pathway

Background

Mesenchymal stromal cells (MSCs) were originally characterized by the ability to differentiate into different mesenchymal lineages in vitro, and their immunomodulatory and trophic functions have recently aroused significant interest in the application of MSCs in cell-based regenerative medicine. However, a major problem in clinical practice is the replicative senescence of MSCs, which limits the cell proliferation potential of MSCs after large-scale expansion. Telomeric zinc finger-associated protein (TZAP), a novel specific telomere-binding protein, was recently found to stimulate telomere trimming and prevent excessive telomere elongation. The aim of this study was to elucidate the role of TZAP in regulating MSCs senescence, differentiation and proliferation.

Method

Primary porcine mesenchymal stromal cells (pMSCs) were isolated from the bone marrow of Tibet minipigs by a noninvasive method in combination with frequent medium changes (FMCs). The deterioration of the pMSCs’ proliferation capacity and their resultant entry into senescence were analyzed by using CCK8 and EdU incorporation assays, SA-β-gal staining and comparisons of the expression levels of cellular senescence markers (p16INK14 and p21) in pMSC cell lines with TZAP overexpression or knockout. The effects of TZAP overexpression or knockout on the differentiation potential of pMSCs were assessed by alizarin red S staining after osteogenic induction or by oil red O staining after adipogenic induction. The effect of TZAP overexpression and the involvement of the p53 signaling pathway were evaluated by detecting changes in ARF, MDM2, P53 and P21 protein levels in pMSCs.

Results

TZAP levels were significantly elevated in late-passage pMSCs compared to those in early-passage pMSCs. We also observed significantly increased levels of the senescence markers p16INK4A and p21. Overexpression of TZAP reduced the differentiation potential of the cells, leading to premature senescence in early-passage pMSCs, while knockout of TZAP led to the opposite phenotype in late-passage pMSCs. Furthermore, overexpression of TZAP activated the P53 pathway (ARF-MDM2-P53-P21WAF/CDKN1A) in vitro. TZAP also downregulated the expression levels of PPARγ and Cebpα, two key modulators of adipogenesis.

Conclusions

This study demonstrates that the level of TZAP is closely related to differentiation potential in pMSCs and affects cellular senescence outcomes via the p53 pathway. Therefore, attenuation of intracellular TZAP levels could be a new strategy for improving the efficiency of pMSCs in cell therapy and tissue engineering applications.

Electronic supplementary material

The online version of this article (10.1186/s12967-019-1820-8) contains supplementary material, which is available to authorized users.

Discovery of biomarkers to identify peri-implant osteolysis before radiographic diagnosis

Peri-implant osteolysis is commonly diagnosed after substantial bone loss has occurred, making revision surgery more challenging. The goal of the current study was to identify urinary biomarkers that differentiate total hip replacement patients who eventually develop osteolysis from patients who do not. We used a repository of 24-h urine samples collected prior to surgery and annually thereafter in 26 patients, 16 who developed osteolysis, and 10 who did not. We examined the markers at radiographic diagnosis, annually for 6 years preceding diagnosis, at the first post-operative sampling point, and pre-operatively. Patients in the osteolysis and non-osteolysis groups were matched according to time post-surgery and did not differ in the male:female ratio or age at surgery. Seven candidate biomarkers were measured, including free deoxypyridinoline (DPD), cross-linked N-telopeptides (NTX), interleukin-6 (IL-6), interleukin-8 (IL-8), osteoprotegerin (OPG), α-crosslaps (α-CTX), and β-crosslaps (β-CTX). As an individual biomarker, DPD demonstrated the highest ability to predict osteolysis, with an area under the curve (AUC) in Receiver Operating Characteristic (ROC) analyses of 0.844 at 6 years prior to diagnosis. A panel of α-CTX and IL-6 was able to identify at-risk patients with an AUC of 0.941 or greater at all post-operative time points and an AUC of 1.000 pre-operatively. The results demonstrate the potential of using non-invasive biomarkers to identify patients at risk for peri-implant osteolysis long before the emergence of radiographic signs. Further, the high accuracy of the pre-operative biomarker levels demonstrates the potential importance of pre-existing, patient-specific factors driving subsequent osteolysis. Study Design © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:2754-2761, 2018.

Alpl prevents bone ageing sensitivity by specifically regulating senescence and differentiation in mesenchymal stem cells

Mutations in the liver/bone/kidney alkaline phosphatase (Alpl) gene cause hypophosphatasia (HPP) and early-onset bone dysplasia, suggesting that this gene is a key factor in human bone development. However, how and where Alpl acts in bone ageing is largely unknown. Here, we determined that ablation of Alpl induces prototypical premature bone ageing characteristics, including bone mass loss and marrow fat gain coupled with elevated expression of p16INK4A (p16) and p53 due to senescence and impaired differentiation in mesenchymal stem cells (MSCs). Mechanistically, Alpl deficiency in MSCs enhances ATP release and reduces ATP hydrolysis. Then, the excessive extracellular ATP is, in turn, internalized by MSCs and causes an elevation in the intracellular ATP level, which consequently inactivates the AMPKα pathway and contributes to the cell fate switch of MSCs. Reactivating AMPKα by metformin treatment successfully prevents premature bone ageing in Alpl+/- mice by improving the function of endogenous MSCs. These results identify a previously unknown role of Alpl in the regulation of ATP-mediated AMPKα alterations that maintain MSC stemness and prevent bone ageing and show that metformin offers a potential therapeutic option.

The participation of fibroblast growth factor 23 (FGF23) in the progression of osteoporosis via JAK/STAT pathway

Osteoporosis (OP) is a major skeletal disorder for the old man. The fibroblast growth factor 23 (FGF23) is a phosphaturic hormone produced by osteoblasts and osteocytes. However, the regulatory mechanisms of FGF23 in the progression of osteoporosis remain poorly understood. This study aims to explore the downstream regulating pathway of FGF23 in postmenopausal osteoporosis. The rat model of osteoporosis was established through ovariectomy (OVX). The investigation demonstrated that the serum levels of FGF23 and the phosphorylation levels of JAK2, STAT1, and STAT3 were up-regulated in the OVX + NVP-BGJ398 group while were down-regulated in the OVX + Anti-FGF23 group than that in the OVX group. Moreover, the JAK2/STAT1/3 inhibitor, AG490 promoted the OVX-induced increase in the osteocalcin, ALP, BALP, TRAP, and CTX-I levels. Besides, AG490 enhanced cartilage lesions and increased TUNEL-positive chondrocytes in the OVX group. In addition, higher protein expression of MMP-1 and MMP-13 and lower expression of COX-II were observed in the OVX + AG490 group than that in the OVX group. Our findings suggested that FGF23 was involved in the progression of osteoporosis via the JAK/STAT signaling pathway.

Bone metabolism dynamics in the early post-transplant period following kidney and liver transplantation

Bone disease contributes to relevant morbidity after solid organ transplantation. Vitamin D has a crucial role for bone metabolism. Activation of vitamin D depends on the endocrine function of both, liver and kidney. Our study assessed key markers of bone metabolism at time of transplantation and 6 months after transplantation among 70 kidney and 70 liver recipients. In 70 kidney recipients 25-OH vitamin D levels did not differ significantly between peri-transplant (median 32.5nmol/l) and 6 months post-transplant (median 41.9nmol/l; P = 0.272). Six months post-transplant median 1, 25-(OH)₂ vitamin D levels increased by >300% (from 9.1 to 36.5ng/l; P<0.001) and median intact parathyroid hormone levels decreased by 68.4% (from 208.7 to 66.0 ng/l; P<0.001). Median β-Crosslaps (CTx) and total procollagen type 1 amino-terminal propeptide (P1NP) decreased by 65.1% (from 1.32 to 0.46ng/ml; P<0.001) and 60.6% (from 158.2 to 62.3ng/ml; P<0.001), respectively. Kidney recipients with incident fractures had significantly lower levels of 1, 25-(OH)₂ vitamin D at time of transplantation and of intact parathyroid hormone 6 months post-transplant. Among 70 liver recipients, 25-OH vitamin D, 1, 25-(OH)₂ vitamin D and intact parathyroid hormone levels were not significantly altered between peri-transplant and 6 months post-transplant. Contrary to kidney recipients, median CTx increased by 60.0% (from 0.45 to 0.72 ng/ml; P = 0.002) and P1NP by 49.3% (from 84.0 to 125.4ng/ml; P = 0.001) in the longitudinal course. Assessed biomarkers didn’t differ between liver recipients with and without fractures. To conclude, the assessed panel of biomarkers proved highly dynamic after liver as well as kidney transplantation in the early post-transplant period. After kidney transplantation a significant gain in 1, 25-(OH)₂ vitamin D combined with a decline in iPTH, CTx and P1NP, whereas after liver transplantation an increase in CTx and P1NP were characteristic.

Biomarkers of collagen turnover are related to annual change in FEV1 in patients with chronic obstructive pulmonary disease within the ECLIPSE study

Background

Change in forced expiratory volume in one second (FEV₁) is important for defining severity of chronic obstructive pulmonary disease (COPD). Serological neoepitope markers of collagen turnover may predict rate of change in FEV₁.

Methods

One thousand COPD subjects from the observational, multicentre, three-year ECLIPSE (Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints) study (NCT00292552, trial registration in February 2006) were included. Matrix metalloproteinase (MMP)-generated fragments of collagen type I, and type VI (C1M and C6M) were assessed in month six serum samples. A random-coefficient model with both a random intercept and a random slope was used to test the ability of the markers to predict post-dose bronchodilator FEV₁ (PD-FEV₁) change over two years adjusting for sex, age, BMI, smoking, bronchodilator reversibility, prior exacerbations, emphysema and chronic bronchitis status at baseline.

Results

Annual change of PD-FEV₁ was estimated from a linear model for the two-year study period. Serum C1M and C6M were independent predictors of lung function change (p = 0.007/0.005). Smoking, bronchodilator reversibility, plasma hsCRP and emphysema were also significant predictors. The effect estimate between annual change in PD-FEV₁ per one standard deviation (1SD) increase of C1M and C6M was +10.4 mL/yr. and +8.6 mL/yr. C1M, and C6M, had a significant association with baseline FEV₁.

Conclusion

We demonstrated that markers of tissue turnover were significantly associated with lung function change. These markers may function as prognostic biomarkers and possibly as efficacy biomarkers in clinical trials focusing on lung function change in COPD.

Trial registration

NCT00292552, Retrospectively registered, trial registration in February 2006.

Electronic supplementary material

The online version of this article (10.1186/s12890-017-0505-4) contains supplementary material, which is available to authorized users.

Low Doses of Simvastatin Potentiate the Effect of Sodium Alendronate in Inhibiting Bone Resorption and Restore Microstructural and Mechanical Bone Properties in Glucocorticoid-Induced Osteoporosis

By using an experimental model of dexamethasone-induced osteoporosis we investigated the effects of different therapeutic schemes combining sodium alendronate (SA) and simvastatin on bone mineral and protein composition, microstructural and mechanical remodeling. Wistar rats were randomized into eight groups: G1: non-osteoporotic; G2: osteoporotic; G3, G4, and G5: osteoporotic+SA (0.2, 0.4, and 0.8 mg/kg, respectively); G6, G7, and G8: osteoporotic+SA (0.2, 0.4, and 0.8 mg/kg, respectively)+simvastatin (0.4, 0.6, and 1 mg/kg, respectively). Osteoporosis was induced by dexamethasone (7 mg/kg, i.m.) once a week for 5 weeks. All treatments were administered for 8 weeks. Dexamethasone increased serum levels of alkaline phosphatase, calcium, phosphorus, and urea, especially in non-treated animals, which showed severe osteoporosis. Dexamethasone also induced bone microstructural fragility and reduced mechanical resistance, which were associated with a marked depletion in mineral mass, collagenous and non-collagenous protein levels in cortical and cancellous bone. Although SA has attenuated osteoporosis severity, the effectiveness of drug therapy was enhanced combining alendronate and simvastatin. The restoration in serum parameters, organic and inorganic bone mass, and mechanical behavior showed a dose-dependent effect that was potentially related to the complementary mechanisms by which each drug acts to induce bone anabolism, accelerating tissue repair.

The Role of Monocyte Percentage in Osteoporosis in Male Rheumatic Diseases

Osteoporosis is easily overlooked in male patients, especially in the field of rheumatic diseases mostly prevalent with female patients, and its link to pathogenesis is still lacking. Attenuated monocyte apoptosis from a transcriptome-wide expression study illustrates the role of monocytes in osteoporosis. This study tested the hypothesis that the monocyte percentage among leukocytes could be a biomarker of osteoporosis in rheumatic diseases. Eighty-seven males with rheumatic diseases were evaluated in rheumatology outpatient clinics for bone mineral density (BMD) and surrogate markers, such as routine peripheral blood parameters and autoantibodies. From the total number of 87 patients included in this study, only 15 met the criteria for diagnosis of osteoporosis. Both age and monocyte percentage remained independently associated with the presence of osteoporosis. Steroid dose (equivalent prednisolone dose) was negatively associated with BMD of the hip area and platelet counts were negatively associated with BMD and T score of the spine area. Besides age, monocyte percentage meets the major requirements for osteoporosis in male rheumatic diseases. A higher monocyte percentage in male rheumatic disease patients, aged over 50 years in this study, and BMD study should be considered in order to reduce the risk of osteoporosis-related fractures.

Association of adiposity indices with bone density and bone turnover in the Chinese population

Associations of adiposity indices with bone mineral density (BMD) and bone turnover markers were evaluated in Chinese participants. Body mass index, fat mass, and lean mass are positively related to BMD in both genders. Subcutaneous fat area was proved to be negatively associated with BMD and positively correlated with osteocalcin in postmenopausal females.

INTRODUCTION

Obesity is highly associated with osteoporosis, but the effect of adipose tissue on bone is contradictory. Our study aimed to assess the associations of adiposity indices with bone mineral density (BMD) and bone turnover markers (BTMs) in the Chinese population.

METHODS

Our study recruited 5215 participants from the Shanghai area, evaluated related anthropometric and biochemical traits in all participants, tested serum BTMs, calculated fat distribution using magnetic resonance imaging (MRI) images and image analysis software, and tested BMD with dual-energy X-ray absorptiometry.

RESULTS

When controlled for age, all adiposity indices were positively correlated with BMD of all sites for both genders. As for the stepwise regression analysis, body mass index (BMI), fat mass, and lean mass were protective for BMD in both genders. However, subcutaneous fat area (SFA) was detrimental for BMD of the L1-4 and femoral neck (β ± SE -0.0742 ± 0.0174; p = 2.11E-05; β ± SE -0.0612 ± 0.0147; p = 3.07E-05). Adiposity indices showed a negative correlation with BTMs adjusting for age, especially with osteocalcin. In the stepwise regression analysis, fat mass was negatively correlated with osteocalcin (β ± SE -8.8712 ± 1.4902; p = 4.17E-09) and lean mass showed a negative correlation with N-terminal procollagen of type I collagen (PINP) for males (β ± SE -0.3169 ± 0.0917; p = 0.0006). In females, BMI and visceral fat area (VFA) were all negatively associated with osteocalcin (β ± SE -0.4423 ± 0.0663; p = 2.85E-11; β ± SE -7.1982 ± 1.1094; p = 9.95E-11), while SFA showed a positive correlation with osteocalcin (β ± SE: 5.5993 ± 1.1753; p = 1.98E-06).

CONCLUSION

BMI, fat mass, and lean mass are proved to be beneficial for BMD in both males and postmenopausal females. SFA is negatively associated with BMD and positively correlated with osteocalcin in postmenopausal females.

Lower serum P1NP/βCTX ratio and hypoalbuminemia are independently associated with osteoporotic nonvertebral fractures in older adults

Purpose

To estimate the discriminative value of serum P1NP/βCTX ratio and albumin levels in hospitalized orthogeriatric patients with and without nonvertebral fractures.

Methods

In 1,239 orthogeriatric patients (mean age 78.1±9.52 years, 69.1% women) including 854 (68.9%) with osteoporotic nonvertebral fractures (455 [36.7%] with hip fracture [HF]) and 385 (31.1%) without fractures, markers of bone formation (procollagen type 1 N-terminal propeptide [P1NP], osteocalcin [OC], and bone resorption (beta-C-terminal cross-linking telopeptide of type 1 collagen [βCTX]), indices of mineral metabolism, and parameters of liver and renal functions were assessed; data on clinical and laboratory characteristics were collected prospectively.

Results

Both lower serum P1NP/βCTX ratio and albumin concentration (as continuous or categorical variables) were independently associated with fracture presence in multivariate logistic regressions. Compared with the highest P1NP/βCTX tertile, the prevalence of HF, after adjustment for multiple covariates, was 3-fold higher in the lowest tertile and 1.5 times higher in the middle tertile; presence of any fracture was 2.3- and 1.6-fold higher, respectively; patients with albumin levels in the lowest tertile had multivariate odds ratio (OR) of 4.6 for HF and 2.8 for any fracture, in the middle tertile the ORs were 2.2 and 1.3, respectively. The P1NP/βCTX <100.0 (median) and hypoalbuminemia (<33 g/L) demonstrated area under the curve values for HF of 0.802 and 0.806, respectively, and for any fractures of 0.711 and 0.706, respectively. When both characteristics were combined, the ORs for HF or any fracture, compared with the nonfractured group, were 7.8 and 3.2, respectively, with an accuracy of 79.6% and 71.6%, respectively.

Conclusions

In orthogeriatric patients, both serum P1NP/βCTX ratio and albumin levels demonstrated an inverse dose–effect relationship with the prevalence of nonvertebral fractures and independently indicated fracture presence with acceptable discriminatory power. Lower P1NP/βCTX (<100) and hypoalbuminemia could be useful simple additive prognostic tools for fracture risk stratification in the elderly.

New Target Sites for Treatment of Osteoporosis

In the last few years, much progress has been achieved in the discovery of new drug target sites for treatment of osteoporotic disorders, one of the main challenging diseases with a large burden for the public health systems. Among these new agents promoting bone formation, shifting the impaired equilibrium between bone anabolism and bone catabolism in the direction of bone synthesis are inorganic polymers, in particular inorganic polyphosphates that show strong stimulatory effects on the expression of bone anabolic marker proteins and hydroxyapatite formation. The bone-forming activity of these polymers can even be enhanced by combination with certain small molecules like quercetin, or if given as functionally active particles with certain divalent cations like strontium ions even showing by itself biological activity. This chapter summarizes recent developments in the search and development of novel anti-osteoporotic agents, with a particular focus on therapeutic approaches based on the potential application of inorganic polymers and combinations.

Vitamin D status and its relationship with bone mineral density in a healthy Iranian population

OBJECTIVES

Considering the controversial results regarding the relationship between vitamin D levels and bone mineral density in different populations, the present study was designed to evaluate this correlation in a healthy Iranian population.

METHODS

Using a random cluster sample of apparently healthy men and women, this multicenter cross-sectional study was carried out among 4450 individuals living in urban areas of five major cities in Iran. Bone mineral density (BMD) values at different sites were analyzed along with the serum levels of 25(OH)D and PTH. Analysis of variance (ANOVA) was used to estimate the main effects, through comparing the mean values of these markers based on the bone mineral density status of the study group in each sex.

RESULTS

25(OH)D levels were inversely correlated with BMD values at total hip (r = -0.062 in men and r = -0.057 in women) and spine (r = -0.076 in men and r = -0.107 in women). After adjusting the data for age, the inverse correlation was no longer statistically significant.

CONCLUSION

Serum 25(OH)D levels are inversely correlated with bone mass values in both sexes.

Plasma levels of N-telopeptide of Type I collagen in periodontal health, disease and after treatment

Background:

To determine plasma concentrations of bone resorption marker cross-linked N-terminal telopeptide (NTx) of Type I collagen in periodontal health, disease and after nonsurgical periodontal therapy in chronic periodontitis group. In addition, to know the association between plasma NTx levels and the different clinical parameters.

Materials and Methods:

Thirty subjects were divided on the basis of their periodontal status and were categorized as Group I: Healthy, Group II: Gingivitis, and Group III: Chronic periodontitis. Group III subjects were treated with scaling and root planing, 6-8 weeks later blood samples were analyzed, and they constituted Group IV. NTx levels in plasma were analyzed by competitive - enzyme-linked immunosorbent assay. All data were analyzed using statistical software (SPSS) (α = 0.05).

Results:

All the samples tested positive for the presence of NTx. The mean NTx concentration was highest in Group III (18.77 nanomole Bone Collagen Equivalent [nm BCE]) and the lowest in Group IV (16.02 nm BCE). The values of Group I and Group II fell between the highest and the lowest values (16.23 nm BCE and 16.70 nm BCE, respectively). The difference in mean NTx levels in Group III and Group IV were statistically significant. NTx levels in all the groups positively correlated with the clinical parameters. All data were analyzed using statistical software (SPSS) (α = 0.05).

Conclusion:

Within the limits of this study, it may be suggested that plasma NTx levels may provide distinguishing data between periodontally healthy diseased sites and after nonsurgical therapy of diseased sites.