PINP as a biological response marker during teriparatide treatment for osteoporosis

Gefitinib Facilitates Bone Fracture Healing via Inhibition of the EGFR Pathway and Counteracting SOX9-driven Bone Metabolic Reprogramming

BACKGROUND/AIM

To investigate the role of epidermal growth factor receptor (EGFR) inhibition in enhancing bone fracture healing by modulating box transcription factor 9 (SOX9) and bone metabolism.

MATERIALS AND METHODS

A rat femoral fracture model was used. Techniques included histological analysis, X-ray scoring, micro-computed tomography, immunohistochemistry, and biomechanical testing. Serum markers were analyzed with enzyme-linked immunosorbent assay, while quantitative real-time polymerase chain reaction and western blotting assessed molecular pathways. Metabolic changes were measured using a Seahorse analyzer. An EGFR inhibitor, gefitinib, was used to examine its impact on periosteal stem cell differentiation and metabolism.

RESULTS

EGFR inhibition improved bone callus formation and quality, increased cartilage callus, and upregulated bone formation markers. Gefitinib enhanced oxidative phosphorylation and fatty acid oxidation, counteracting negative effects from lipid-reduced serum on osteoblastic differentiation of periosteal stem cell. SOX9 overexpression reduced the benefits of EGFR inhibition.

CONCLUSION

Gefitinib enhances bone fracture healing by modulating lipid metabolism through SOX9, suggesting its potential as a therapeutic agent for improving fracture outcomes.

Treatment period and changes in bone markers according to the application of teriparatide in treating medication-related osteonecrosis of the jaw

BACKGROUND

This study aimed to explore the effects of teriparatide (TPTD) on treatment duration, surgical procedures, and bone turnover markers in medication-related osteonecrosis of the jaw (MRONJ).

METHODS

We analyzed 76 patients with MRONJ post-treatment and divided them into conservative/surgical and TPTD/non-TPTD groups. Key assessments included treatment duration, surgery count, and changes in bone markers (serum C-terminal telopeptide of type 1 collagen [CTX], osteocalcin [OC], procollagen type 1 N-terminal propeptide [P1NP], parathyroid hormone [PTH], 25-OH-vitamin D [25(OH)D], calcium, and inorganic phosphorus) measured at the initial and post-treatment stages.

RESULTS

TPTD-treated surgical patients experienced shorter treatment periods and underwent fewer surgeries than did non-TPTD counterparts. Post-treatment, both groups showed significant increases in CTX, OC, and 25(OH)D levels. P1NP elevation was significant only in the non-TPTD group. Although the PTH levels decreased in both groups, the difference was not statistically significant. Calcium and phosphorus levels increased in both groups, but only calcium levels increased significantly in the TPTD group. Additionally, TPTD-treated patients showed significant improvements in T-scores, particularly in the lumbar spine and femur neck, compared to the non-TPTD group.

CONCLUSIONS

TPTD administration during MRONJ treatment potentially reduces the need for surgical intervention and accelerates recovery, significantly affecting bone metabolism. These findings highlight TPTD's role in enhancing the efficacy of MRONJ treatment. TPTD could potentially offer the dual benefit of promoting bone healing and reducing the need for surgical intervention, thus improving overall outcomes for patients with MRONJ.

Aptamers as Diagnostic and Therapeutic Agents for Aging and Age-Related Diseases

In the 21st century, the demographic shift toward an aging population has posed a significant challenge, particularly with respect to age-related diseases, which constitute a major threat to human health. Accordingly, the detection, prevention, and treatment of aging and age-related diseases have become critical issues, and the introduction of novel molecular recognition elements, called aptamers, has been considered. Aptamers, a class of oligonucleotides, can bind to target molecules with high specificity. In addition, aptamers exhibit superior stability, biocompatibility, and applicability, rendering them promising tools for the diagnosis and treatment of human diseases. In this paper, we present a comprehensive overview of aptamers, systematic evolution of ligands by exponential enrichment (SELEX), biomarkers associated with aging, as well as aptamer-based diagnostic and therapeutic platforms. Finally, the limitations associated with predicting and preventing age-related conditions are discussed, along with potential solutions based on advanced technologies and theoretical approaches.

Osteoking inhibits apoptosis of BMSCs in osteoporotic rats via PI3K/AKT signaling pathway

In China, Osteoking is a commonly used treatment and preventive measure for osteoporosis. The pathophysiology of osteoporosis is closely associated with apoptosis; however, it remains unclear whether the role of Osteoking in promoting bone formation is linked to apoptosis.

AIM OF STUDY

This study aims to investigate whether Osteoking inhibits apoptosis of BMSCs in osteoporotic rats via the PI3K/AKT signaling pathway and to conduct a detailed exploration of this mechanism. The goal is to provide a theoretical basis for the clinical application of Osteoking in osteoporosis treatment.

METHODS

A rat model of osteoporosis was established through bilateral ovariectomy (OVX), followed by treatment with Osteoking. After ten weeks of therapy, BMD was evaluated. The biomechanics of the left tibia were measured, the left femur was sequenced, and the right tibia was stained using histomorphometric and Masson's staining methods. Peripheral serum was collected to measure bone-related markers, including E2, PINP, and CTX. RNA-Seq results were verified using the remaining bone samples. Comparative analysis demonstrated the efficacy of Osteoking in treating osteoporosis and provided preliminary insights into the underlying mechanisms. Primary BMSCs were cultured using bone marrow apposition. CCK8 assays were conducted to screen the intervention conditions of Osteoking and LY294002. Various concentrations of Osteoking-containing serum and LY294002 were tested separately to determine the optimal intervention concentration for drug delivery. The impact of Osteoking on lipid formation was also evaluated. Following treatment of BMSCs from OVX rats with Sham serum, OVX serum, OVX + LY294002 serum, and Osteoking + LY294002 serum, the expression of PI3K/AKT/mTOR, osteogenesis-related regulatory factors, and apoptosis-related regulatory factors was assessed. Flow cytometry was employed to evaluate apoptosis in BMSCs.

RESULTS

Osteoking significantly improved whole-body BMD and bone biomechanical indices in OVX rats. It also significantly elevated the serum levels of E2 and PINP while reducing the level of CTX, which significantly improved bone microstructure and promoted new bone formation. RNA-seq analysis indicated that the therapeutic mechanism involved the PI3K/AKT signaling pathway. Osteoking increased the expression of RUNX2 and decreased the expression of PPAR-γ, a marker of lipogenesis, in OVX rats. Extraction of BMSCs for subsequent studies revealed a significant reduction in proliferation and osteogenic differentiation, along with an increase in lipogenic differentiation, in the OVX group. Osteoking treatment inhibited the expression of PPAR-γ and increased the expression of RUNX2 in BMSCs. Additionally, Osteoking reversed the LY294002-mediated inhibition of PI3K/AKT/mTOR signaling pathway activation, increased the expression of the apoptosis-protecting protein Bcl2, and decreased the expression of apoptosis-associated proteins Caspase3 and Bax.

CONCLUSION

Osteoking markedly improved bone microstructure, biomechanics, and bone density in OVX rats. Osteoking-containing serum reversed the imbalance in lineage differentiation in OVX rats, characterized by reduced osteogenic differentiation and increased lipid differentiation of BMSCs. Furthermore, Osteoking-containing serum significantly increased BMSC proliferation and prevented apoptosis in OVX rats through the PI3K/AKT signaling pathway.

The comparison of serum bone-turnover markers in different stage of chronic kidney disease and the associated impact of intradialytic cycling in patients with end-stage renal disease

INTRODUCTION

Bone turnover markers reflected the bone remodeling process and bone health in clinical studies. Studies on variation of bone remodeling markers in different stage CKD were scant, and this study investigated the role of bedside intradialytic cycling in altering concentrations of bone-remodeling markers in patients with end-stage renal disease (ESRD).

MATERIALS AND METHODS

Participants were segmented into four groups: a group with eGFR >60 ml/min/1.73 m2, a chronic kidney disease group with eGFR 15-60 mL/min/1.73 m2), an ESRD group with an exercise intervention, and an ESRD group with standard care. Comparison of bone turnover markers was performed among groups. The intervention consisting of 12 weeks of intradialytic cycling was performed during dialysis. The variation of bone-remodeling markers was compared between the ESRD with exercise along with the ESRD with standard care after 12-week monitoring.

RESULTS

Bone-formative marker levels (bone-specific alkaline phosphatase and procollagen type 1 amino-terminal propeptide, P1NP) were higher in ESRD patients than in non-ESRD patients and were correlated with indoxyl sulfate and intact parathyroid hormone concentrations (p < 0.05). Postexercise concentrations of tartrate-resistant acid phosphatase-5b (p = 0.003) and N-terminal telopeptide-1 (p = 0.001) had increased in the ESRD patients after 12 weeks of bedside cycling. Bone-formative marker concentration was not altered in the exercise group after cycling.

CONCLUSION

Bone-formative marker concentrations increased with the severity of chronic kidney disease. Bone formative markers concentration increased along with CKD severity. We demonstrated the bone resorptive markers tartrate-resistant acid phosphatase-5b and N-terminal telopeptide-1 increased after intradialytic cycling in ESRD patients.

Correlation Between Bone Metabolism Indices and Osteoporotic Thoracolumbar Vertebrae Fracture in Postmenopausal Women

Background

This study aims to explore the correlation between bone metabolism indices and osteoporotic thoracolumbar vertebrae fracture (OTVF) in postmenopausal women.

Methods

A total of 447 female patients with postmenopause and underwent OTVF in our hospital were selected as group A. Three hundred eighty-seven out-patients without fractures were selected as group B. Bone metabolism index including the serum levels of total Serum procollagen type N-terminal propeptide (tPINP), the age-related type I cross linked C-telopeptide (β-CTX) and 25-hydroxyvitamin D (25-OHD) were collected and compared. The relation between bone metabolism indices and OTVF was analyzed.

Results

The mean tPINP in group A was 61.72 ± 28.43, which was notably higher than group B (P < 0.01). Meanwhile, greater β-CTX were higher founded in group A than group B (0.778 ± 0.316 vs 0.669 ± 0.303 μg/l). However, the 25-OHD in group A was significantly lower than that in group B (P < 0.05). Multivariate logistic regression analysis revealed that the serum level of tPINP (OR: 0.008, P = 0.011), the serum level of β-CTX (OR: 0.805, P = 0.002) and the serum level of 25-OHD (OR: -0.029, P = 0.003) were independently correlated with postmenopausal OTVF.

Conclusion

Bone metabolic markers play an important role in predicting OTVF. As a reflection of bone mass and bone strength, BMD is inadequate in predicting OTVF. High expression of bone metabolism indicators β-CTX, tPINP and relatively low expression of 25-OHD suggest an increased risk of OTVF. Early detection of postmenopausal bone metabolism abnormalities can be used for early intervention to reduce the incidence of OTVF.

Gastrointestinal health and serum proteins are associated with BMD in postmenopausal women: a cross-sectional study

BACKGROUND

With increasing age, the social and economic burdens of postmenopausal osteoporosis are steadily increasing. This study aimed to investigate the factors that influence the development of postmenopausal osteoporosis.

METHODS

Postmenopausal women at the Affiliated Hospital of Jiangnan University from January 2023 to December 2023 were recruited for BMD examination. The patients were divided into a normal group, an osteopenia group and an osteoporosis group according to their T value. Questionnaires, including the Gastrointestinal Symptom Rating Scale and Short Form 12, were administered through face-to-face interviews. Bone turnover markers and serum protein levels of Fasting venous blood were detected.

RESULTS

A total of 222 postmenopausal women met the inclusion criteria were recruited. Univariate analysis revealed statistically significant differences in age, education, BMI, supplementation with soy products, supplementation with dairy products, supplementation with other nutritional supplements, exercise frequency, gastrointestinal symptom score, quality of life, 25(OH)D, total protein, albumin and prealbumin among the three groups (P < 0.05). Pearson correlation analysis revealed that gastrointestinal symptoms (r = -0.518, P < 0.01) was negatively correlated with BMD in postmenopausal women, while PCS (r = 0.194, P = 0.004), MCS (r = 0.305, P < 0.01), 25(OH)D (r = 0.531, P < 0.01), total protein (r = 0.324, P < 0.01), albumin (r = 0.341, P < 0.01) and prealbumin (r = 0.259, P < 0.01) were positively correlated with BMD. Logistic regression analysis revealed that both the gastrointestinal symptom score and serum 25(OH)D level were found to have a significant association with BMD (both P < 0.01). This association remained significant even after adjusting for age, BMI, education level, dietary habits, and exercise frequency.

CONCLUSION

Gastrointestinal symptoms and serum 25(OH)D elevel are associated with increased risk of osteoporosis in postmenopausal women and may be useful in predicting osteoporosis in postmenopausal women.

Effectiveness of anthocyanin-rich foods on bone remodeling biomarkers of middle-aged and older adults at risk of osteoporosis: a systematic review, meta-analysis, and meta-regression

CONTEXT

Current osteoporosis pharmacological treatment has undesirable side effects. There is increasing focus on naturally derived food substances that contain phytonutrients with antioxidant effects in promoting health and regulating immune response.

OBJECTIVE

This review aims to systematically evaluate the effectiveness of anthocyanin-rich foods on bone remodeling biomarkers in middle-aged and older adults (≥40 y old) at risk of osteoporosis.

DATA SOURCES

Randomized controlled trials were searched on 8 bibliographic databases of PubMed, Embase, Scopus, Web of Science, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Food Science and Technology Abstracts, Cochrane Library, and ProQuest.

DATA EXTRACTION AND ANALYSIS

Thirteen studies were included in the meta-analysis. Receptor activator of nuclear factor kappa-B ligand (RANKL) is exhibited from osteoblastic cells that gathered osteoclasts to bone sites for bone resorption, accelerating bone loss. Anthocyanin-rich food consumption showed statistically nonsignificant effects, with no substantial heterogeneity on bone remodeling biomarkers. However, there was a significant increase in lumbar spine L1-L4 bone mineral density. Mild-to-small effects were seen to largely favor the consumption of anthocyanin-rich foods. Berries (d = -0.44) have a larger effect size of RANKL than plums (d = 0.18), with statistically significant subgroup differences. Random-effects meta-regression found body mass index, total attrition rate, total energy, and dietary carbohydrate and fat intake were significant covariates for the effect size of RANKL. All outcomes had low certainty of evidence.

CONCLUSION

Anthocyanin-rich foods may improve bone health in middle-aged and older adults at risk of osteoporosis. This review contributes to the growing interest in nutrient-rich foods as a low-cost and modifiable alternative to promote human health and reduce disease burden. Future high-quality studies with larger sample sizes and longer treatment durations are required to fully understand the effect of anthocyanin-rich foods on bone health.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42022367136.

Long-term second-generation antipsychotics decreases bone formation and resorption in male patients with schizophrenia

RATIONALE

Patients with schizophrenia with second-generation antipsychotics (SGAs) treatment have shown an increased risk of bone fragility and susceptibility to fracture; however, it is still unclear whether this risk is derived from the effect of antipsychotics on balance of bone metabolism.

OBJECTIVES

We investigated the changes of two bone turnover biomarkers (BTMs) concentrations in people with schizophrenia receiving SGAs: procollagen type I aminoterminal propeptide (PINP) and C-terminal telopeptide of type I collagen (CTX-1) as BTMs of osteogenesis and bone resorption, respectively, to explore how antipsychotics contribute to bone fragility.

METHODS

We recruited 59 Chinese male patients with schizophrenia (32 drug-naïve first-episode (DNFE) patients and 27 chronic patients) to undergo 8 weeks SGAs treatment. Fasting peripheral blood samples of pre- and posttreatment were collected, plasma levels of PINP and CTX-1 were measured.

RESULTS

The interaction effects of group and time on PINP and CTX-1 concentrations were found (P = .016 and P = .008). There was a significant decrease for both BTMs concentrations of the posttreatment compared to the pretreatment (P<.001 and P = .003). Chronic patients had significantly higher changes of BTMs concentrations compared to DNFE patients (P = .048 and P = .024). There was a positive correlation of the two BTMs of pretreatment with disease course in DNFE group (r = .37, P = .039;r = .38, P = .035) and a negative correlation of PINP of pretreatment with age in the chronic group (r=-.40, P = .039).

CONCLUSION

Long-term SGAs medication inhibited osteogenesis in a dose- and time-dependent manner and damaged the balance of bone formation and bone resorption.

Association between P1NP value and increases in bone mineral density in patients with postmenopausal osteoporosis treated with romosozumab

OBJECTIVES

The present study aimed to investigate the effectiveness of treatment with romosozumab for 1 year and association between bone turnover markers and changes in bone mineral density (BMD) in patients with postmenopausal osteoporosis.

METHODS

Participants were 53 treatment-naïve postmenopausal osteoporosis patients. Correlations of per cent changes (Δ) in lumbar (L) and total hip (TH) BMD 12 months after initiating romosozumab with baseline demographic factors and parameters of N-terminal propeptide of Type 1 collagen (P1NP) and tartrate-resistant acid phosphatase-5b at baseline and Months 1, 3, and 6 were assessed. Multiple regression analysis was performed on factors significantly correlated with ΔL-BMD and ΔTH-BMD at Month 12.

RESULTS

ΔL-BMD and ΔTH-BMD at Month 12 were 17.5% and 8.1%, respectively. Multiple regression analysis revealed that a high P1NP value at Month 3 predicted large increases in L-BMD and TH-BMD at Month 12. High total amount of P1NP values from baseline to Month 6 was associated with large increases in L-BMD and TH-BMD at Month 12 and was most strongly correlated with the P1NP value at Month 3.

CONCLUSIONS

A high P1NP value at Month 3 predicted large increases in both L-BMD and TH-BMD at Month 12 in postmenopausal osteoporosis patients treated with romosozumab.

Osteoporosis treatment: current drugs and future developments

Osteoporosis is a common systemic metabolic disease characterized by a decrease in bone density and bone mass, destruction of bone tissue microstructure, and increased bone fragility leading to fracture susceptibility. Pharmacological treatment of osteoporosis is the focus of current research, and anti-osteoporosis drugs usually play a role in inhibiting bone resorption, promoting bone formation, and having a dual role. However, most of the drugs have the disadvantages of single target and high toxic and side effects. There are many types of traditional Chinese medicines (TCM), from a wide range of sources and mostly plants. Herbal plants have unique advantages in regulating the relationship between osteoporosis and the immune system, acupuncture therapy has significant therapeutic effects in combination with medicine for osteoporosis. The target cells and specific molecular mechanisms of TCM in preventing and treating osteoporosis have not been fully elucidated. At present, there is a lack of comprehensive understanding of the pathological mechanism of the disease. Therefore, a better understanding of the pathological signaling pathways and key molecules involved in the pathogenesis of osteoporosis is crucial for the design of therapeutic targets and drug development. In this paper, we review the development and current status of anti-osteoporosis drugs currently in clinical application and under development to provide relevant basis and reference for drug prevention and treatment of osteoporosis, with the aim of promoting pharmacological research and new drug development.

A comprehensive approach for osteoporosis detection through chest CT analysis and bone turnover markers: harnessing radiomics and deep learning techniques

Purpose

The main objective of this study is to assess the possibility of using radiomics, deep learning, and transfer learning methods for the analysis of chest CT scans. An additional aim is to combine these techniques with bone turnover markers to identify and screen for osteoporosis in patients.

Method

A total of 488 patients who had undergone chest CT and bone turnover marker testing, and had known bone mineral density, were included in this study. ITK-SNAP software was used to delineate regions of interest, while radiomics features were extracted using Python. Multiple 2D and 3D deep learning models were trained to identify these regions of interest. The effectiveness of these techniques in screening for osteoporosis in patients was compared.

Result

Clinical models based on gender, age, and β-cross achieved an accuracy of 0.698 and an AUC of 0.665. Radiomics models, which utilized 14 selected radiomics features, achieved a maximum accuracy of 0.750 and an AUC of 0.739. The test group yielded promising results: the 2D Deep Learning model achieved an accuracy of 0.812 and an AUC of 0.855, while the 3D Deep Learning model performed even better with an accuracy of 0.854 and an AUC of 0.906. Similarly, the 2D Transfer Learning model achieved an accuracy of 0.854 and an AUC of 0.880, whereas the 3D Transfer Learning model exhibited an accuracy of 0.740 and an AUC of 0.737. Overall, the application of 3D deep learning and 2D transfer learning techniques on chest CT scans showed excellent screening performance in the context of osteoporosis.

Conclusion

Bone turnover markers may not be necessary for osteoporosis screening, as 3D deep learning and 2D transfer learning techniques utilizing chest CT scans proved to be equally effective alternatives.

Recombinant Human Parathyroid Hormone Biocomposite Promotes Bone-to-Tendon Interface Healing by Enhancing Tenogenesis, Chondrogenesis, and Osteogenesis in a Rabbit Model of Chronic Rotator Cuff Tears

PURPOSE

To investigate the effect of recombinant human parathyroid hormone (rhPTH) biocomposite on bone-to-tendon interface (BTI) healing for surgical repair of a chronic rotator cuff tear (RCT) model of rabbit, focusing on genetic, histologic, biomechanical and micro-computed tomography (CT) evaluations.

METHODS

Sixty-four rabbits were equally assigned to the 4 groups: saline injection (group A), nanofiber sheet alone (group B), rhPTH-soaked nanofiber sheet (nanofiber sheet was soaked with rhPTH, group C), and rhPTH biocomposite (rhPTH permeated the nanofiber sheet by coaxial electrospinning, group D). The release kinetics of rhPTH (groups C and D) was examined for 6 weeks in vitro. Nanofiber scaffolds were implanted on the surface of the repair site 6 weeks after the induction of chronic RCT. Genetic and histologic analyses were conducted 4 weeks after surgery. Furthermore, genetic, histologic, biomechanical, micro-CT, and serologic analyses were performed 12 weeks after surgery.

RESULTS

In vivo, group D showed the highest collagen type I alpha 1 (COL1A1), collagen type III alpha 1 (COL3A1), and bone morphogenetic protein 2 (BMP-2) messenger RNA (mRNA) expression levels (all P < .001) 4 weeks after surgery; however, there were no differences between groups at 12 weeks postsurgery. After 12 weeks postsurgery, group D showed better collagen fiber continuity and orientation, denser collagen fibers, more mature bone-to-tendon junction, and greater fibrocartilage layer formation compared with the other groups (all P < .05). Furthermore, group D showed the highest load-to-failure rate (28.9 ± 2.0 N/kg for group A, 30.1 ± 3.3 N/kg for group B, 39.7 ± 2.7 N/kg for group C, and 48.2 ± 4.5 N/kg for group D, P < .001) and micro-CT outcomes, including bone and tissue mineral density, and bone volume/total volume rate (all P < .001) at 12 weeks postsurgery.

CONCLUSIONS

In comparison to rhPTH-soaked nanofiber sheet and the other control groups, rhPTH biocomposite effectively accelerated BTI healing by enhancing the mRNA expression levels of COL1A1, COL3A1, and BMP-2 at an early stage and achieving tenogenesis, chondrogenesis, and osteogenesis at 12 weeks after surgical repair of a chronic RCT model of rabbit.

CLINICAL RELEVANCE

The present study might be a transitional study to demonstrate the efficacy of rhPTH biocomposites on BTI healing for surgical repair of chronic RCTs as an adaptable polymer biomaterial in humans.

Teriparatide as Treatment for Severe Osteoporosis in Lung Transplant Recipients

Osteoporosis and osteopenia are common in lung transplant (LTx) recipients, with a significantly increased incidence compared to other non-lung solid organ transplant patients. Despite high fracture rates, including in patients treated with antiresorptive medications, there are limited data on the use of anabolic treatments in LTx recipients. We present clinical, biochemical and bone mineral density data for 3 patients with severe osteoporosis treated with teriparatide 20 micrograms daily for 18 months post-LTx. Prednisone doses ranged between 5 and 10 mg daily throughout the treatment period. All patients had previously received zoledronate (last dose 12-24 months prior to teriparatide). Bone turnover was monitored repeatedly during treatment in one patient. Following completion of teriparatide, all patients received consolidation treatment with 4 mg zoledronate. Bone density was measured prior and within 6 to 12 months after completion of teriparatide. All 3 patients experienced an increase in bone density at the lumbar spine (median +12%; range, 2%-14%) and total proximal femur (median +8%, range, 8%-10%). No adverse effects were observed. Given that severe osteoporosis is highly prevalent in LTx patients, teriparatide should be further studied as a treatment in this clinical setting. Our cases suggest it is safe and effective.

The Use of Bone-Turnover Markers in Asia-Pacific Populations

Bone-turnover marker (BTM) measurements in the blood or urine reflect the bone-remodeling rate and may be useful for studying and clinically managing metabolic bone diseases. Substantial evidence supporting the diagnostic use of BTMs has accumulated in recent years, together with the publication of several guidelines. Most clinical trials and observational and reference-interval studies have been performed in the Northern Hemisphere and have mainly involved Caucasian populations. This review focuses on the available data for populations from the Asia-Pacific region and offers guidance for using BTMs as diagnostic biomarkers in these populations. The procollagen I N-terminal propeptide and β-isomerized C-terminal telopeptide of type-I collagen (measured in plasma) are reference BTMs used for investigating osteoporosis in clinical settings. Premenopausal reference intervals (established for use with Asia-Pacific populations) and reference change values and treatment targets (used to monitor osteoporosis treatment) help guide the management of osteoporosis. Measuring BTMs that are not affected by renal failure, such as the bone-specific isoenzyme alkaline phosphatase and tartrate-resistant acid phosphatase 5b, may be advantageous for patients with advanced chronic kidney disease. Further studies of the use of BTMs in individuals with metabolic bone disease, coupled with the harmonization of commercial assays to provide equivalent results, will further enhance their clinical applications.

Analyzing the factors associated with efficacy among teriparatide treatment in postmenopausal women with osteoporosis

BACKGROUND

Teriparatide (TPTD) is a widely used anabolic agent for the treatment of osteoporosis. Several factors have been identified to be related to bone mineral density (BMD) increase in anti-osteoporosis treatment with other agents; however, there has been no systematic analysis to summarize the associated determinants of BMD reaction to daily teriparatide treatment.

METHODS

In this retrospective study, we performed a comprehensive investigation involving not only clinical data but also several relevant lifestyle factors to be examined for their potential contribution to BMD response. This post-hoc analysis included 258 post-menopaused patients with osteoporosis who received TPTD at 20 µg/day for 12 months. Univariate and multivariate analyses were conducted to distinguish the response variables of lumbar spine (LS) BMD transformation, the principal outcome measure of efficacy, from the baseline at 12 months.

RESULTS

Twelve months of TPTD treatment resulted in an absolute 0.39 ± 0.37 increase in T-score of LS BMD. Gastrointestinal disease, prior bisphosphonate or glucocorticoid treatment, no vitamin K2 supplementation, low levels of serum 25(OH)D and PINP, weak increment of PINP and β-CTX at 3 months, unhealthy lifestyle (excessive smoking, tea, coffee, and drinking), vegetarian diet pattern, low ALT level, and high BMD at baseline were determined by univariate analyses to be related to the weak reaction of TPTD treatment (P < 0.10). In the multiple regression model, postmenopausal women with vitamin K2 supplementation, higher baseline serum 25(OH)D level, and higher PINP concentration at 3 months indicated a good reaction of LS BMD at 12 months (P < 0.05). Patients with gastrointestinal disease, prior bisphosphonate and glucocorticoid treatment, vegetarian diet pattern, and higher baseline BMD were significantly more likely to have a lower absolute LS BMD response compared to patients without these characteristics (P < 0.05). Further analysis confirmed the negative effect of unhealthy lifestyle on TPTD treatment.

CONCLUSION

Our results emphasize the significance of a comprehensive assessment of clinical or lifestyle-related characteristics of postmenopausal women with osteoporosis in the management of TPTD therapy in routine care.

Identification of the transcriptome signatures and immune-inflammatory responses in postmenopausal osteoporosis

Postmenopausal osteoporosis is the most common type of osteoporosis in women. To date, little is known about their transcriptome signatures, although biomarkers from peripheral blood mononuclear cells are attractive for postmenopausal osteoporosis diagnoses. Here, we performed bulk RNA sequencing of 206 samples (124 postmenopausal osteoporosis and 82 normal samples) and described the clinical phenotypic characteristics of postmenopausal women. We then highlighted the gene set enrichment analyses between the extreme T-score group and the heathy control group, revealing that some immune-inflammatory responses were enhanced in postmenopausal osteoporosis, with representative pathways including the mitogen-activated protein kinase (NES = 1.6, FDR <0.11) pathway and B_CELL_RECEPTOR (NES = 1.69, FDR <0.15) pathway. Finally, we developed a combined risk prediction model based on lasso-logistic regression to predict postmenopausal osteoporosis, which combined eleven genes (PTGS2, CXCL16, NECAP1, RPS23, SSR3, CD74, IL4R, BTBD2, PIGS, LILRA2, MAP3K11) and three pieces of clinical information (age, procollagen I N-terminal propeptide, β isomer of C-terminal telopeptide of type I) and provided the best prediction ability (AUC = 0.97). Taken together, this study filled a gap in the large-scale transcriptome signature profiles and revealed the close relationship between immune-inflammatory responses and postmenopausal osteoporosis, providing a unique perspective for understanding the occurrence and development of postmenopausal osteoporosis.

Changes in Serum Concentrations of Bone Turnover Markers in Healthy Pregnant Women

Background

Changes in bone metabolism during pregnancy have not received sufficient attention because of the lack of effective screening tools. Bone turnover markers (BTMs) could reflect the changes of bone metabolism. Currently, reference intervals for bone metabolism during normal pregnancy are inconclusive. This study aimed to determine reference intervals for BTMs in pregnant women taking prenatal care and to facilitate clinical research on diseases affecting bone metabolism during pregnancy.

Methods

We surveyed 120 low-risk pregnant women attending routine antenatal care from January 2020 to March 2020. The serum levels of procollagen type I N-propeptide (PINP), N-terminal osteocalcin (N-MID), and C-terminal telopeptide of type I collagen (β-CTX) were measured in the first trimester (<13 weeks), second trimester (14-27 weeks), and third trimester (>28 weeks). Reference intervals for BTMs during pregnancy were analyzed. The Kruskal-Wallis test and paired t-test are used to analyze differences between groups. Spearman correlation coefficients expressed the measure of linear association.

Results

The bone resorption marker β-CTX in third trimester increases compared to the first trimester and the second trimester (P < 0.001, P < 0.001). The bone formation markers PINP and N-MID were decreased from the first trimester to the second trimester (P = 0.01, P < 0.001) and then raised from the second trimester to the third trimester (P < 0.001, P < 0.001). Two indices of bone turnover rate, β-CTX/PINP and β-CTX/N-MID, were increased from the first trimester to the second trimester (P < 0.001, P < 0.001) and then decreased from the second trimester to the third trimester (P = 0.02, P < 0.001).

Conclusion

This study established reference intervals for BTMs in pregnant women and observed the changes in BTMs during the different trimesters of pregnancy. The present findings can help in clinical monitoring of the effects of pregnancy diseases on the bone metabolism of pregnant women.

Aconine attenuates osteoclast-mediated bone resorption and ferroptosis to improve osteoporosis via inhibiting NF-κB signaling

Osteoporosis (OP), a prevalent public health concern primarily caused by osteoclast-induced bone resorption, requires potential therapeutic interventions. Natural compounds show potential as therapeutics for postmenopausal OP. Emerging evidence from in vitro osteoclastogenesis assay suggests that aconine (AC) serves as an osteoclast differentiation regulator without causing cytotoxicity. However, the in vivo functions of AC in various OP models need clarification. To address this, we administered intraperitoneal injections of AC to ovariectomy (OVX)-induced OP mice for 8 weeks and found that AC effectively reversed the OP phenotype of OVX mice, leading to a reduction in vertebral bone loss and restoration of high bone turnover markers. Specifically, AC significantly suppressed osteoclastogenesis in vivo and in vitro by decreasing the expression of osteoclast-specific genes such as NFATc1, c-Fos, Cathepsin K, and Mmp9. Importantly, AC can regulate osteoclast ferroptosis by suppressing Gpx4 and upregulating Acsl4, which is achieved through inhibition of the phosphorylation of I-κB and p65 in the NF-κB signaling pathway. These findings suggest that AC is a potential therapeutic option for managing OP by suppressing NF-κB signaling-mediated osteoclast ferroptosis and formation.

Combined detection of vitamin D, CRP and TNF-α has high predictive value for osteoporosis in elderly men

OBJECTIVE

To observe the predictive value of 25-hydroxyvitamin D3 (25(OH)D3), C-reactive protein (CRP), and tumor necrosis factor-α (TNF-α) levels for osteoporosis in elderly men.

METHODS

A retrospective analysis was conducted in 122 elderly male patients that were tested in The Affiliated Hospital of Xinyang Vocational and Technical College between January 2020 and May 2022. The patients were divided into an osteoporosis group (OG, n = 77) and a control group (CG, n = 45) according to the results of bone mineral density. The formula N = Z^2*(P*(1-P))/E^2 was used to calculate the required sample size (N) for a given confidence interval (Z), total error (E), and proportion (P) of the target population. The proportion (P) is often assumed to be 0.5 and not randomly distributed across the population. The levels of cross-linked C-terminal telopeptide of type I collagen (CTX-I), procollagen type I N-terminal propeptide (PINP), intact parathyroid hormone (iPTH), osteocalcin (OC), and serum levels of 25(OH)D3, CRP, and TNF-α were measured and compared between the two groups. Pearson correlation was used to analyze the relationship between the parameters. The predictive value of 25(OH)D3, CRP and TNF-α for osteoporosis was also analyzed using receiver operating characteristic (ROC) curves. Logistic multivariate analysis was performed to analyze the risk factors for osteoporosis in elderly men.

RESULTS

Compared with the CG, the OG exhibited evidently lower serum 25(OH)D3, but significantly higher CRP and TNF-α (P < 0.05). Pearson correlation demonstrated that the bone mineral density was negatively correlated with CTX-I, PINP, serum CRP and TNF-α, whereas it was positively correlated with OC and 25(OH)D3 in elderly men. The areas under the ROC curve (AUCs) of serum 25(OH)D3, CRP and TNF-α were identified as 0.931, 0.878 and 0.846, respectively, and the AUC of the combined detection of the three was 0.991. Furthermore, age, CTX-I, PINP, OC, 25(OH)D3, as well as serum CRP and TNF-α were identified as risk factors for osteoporosis among elderly men.

CONCLUSION

Serum 25(OH)D3, CRP, and TNF-α are associated with osteoporosis in elderly men, and can serve as predictors for osteoporosis.

Hydroxyapatite-chitosan composites derived from sea cucumbers and shrimp shells ameliorate femoral bone defects in an albino rat model

Background and Aim

A bone defect is defined as a critically sized autologous bone and a bone gap. Bone grafting is one of the most commonly used surgical methods to enhance bone regeneration in orthopedic procedures. A composite of collagen, hydroxyapatite (HA), and chitosan (Ch) is suitable as a bone matrix and stimulates ossification. This study aimed to evaluate the use of natural HA-Ch composites derived from sea cucumbers and shrimp shells and quantify the levels of cytokines, polymorphonuclear neutrophils (PMNs), serum liver enzymes, calcium, phosphate, and procollagen type 1 N-terminal propeptide (PINP) in albino rats with femoral bone defects.

Materials and Methods

A total of 48 albino rats with femoral bone defects were divided into 4 groups (n = 12 each): (C-) placebo, (C+) polyethylene glycol, (T1) HA, and (T2) HA-Ch groups. Each group was divided into two subgroups (n = 6 each), with euthanization on 7- and 42-day post-treatment, respectively. Procollagen Type 1 N-terminal propeptide and the cytokines interleukin (IL)-4, IL-6, IL-10, and tumor necrosis factor-alpha were quantified using enzyme-linked immunosorbent assay. Flow cytometry was performed to evaluate PMNs. A clinical chemistry analyzer was used to measure the serum levels of liver enzymes, calcium, and phosphate.

Results

There was a significant decrease in the level of IL-6 on 7 days and in the level of IL-10 on 42 days in the HA-Ch group. The level of PMNs also decreased significantly on 7 and 42 days in the HA-Ch group. Regarding serum liver enzymes, alkaline phosphatase (ALP) levels in the HA-Ch group increased significantly on 42 days. Calcium and phosphate levels increased significantly on 7 and 42 days in the HA and HA-Ch groups, and PINP levels increased significantly on 7 and 42 days in the HA-Ch group.

Conclusion

The HA-Ch composite derived from sea cucumbers and shrimp shells ameliorated femoral bone defects in albino rats. The HA-Ch composite modulated the levels of IL-6, IL-10, PMNs, ALP, calcium, phosphate, and PINP on 7- and 42-day post-treatment.

Predisposing factors for a second fragile hip fracture in a population of 1130 patients with hip fractures, treated at Oulu University Hospital in 2013-2016: a retrospective study

OBJECTIVE

The life-time risk of a second fragile hip fracture is 8.4%, but the risk factors that predispose to a second hip fracture remain unresolved. This study aimed to define risk factors that predisposed patients to a second hip fracture.

METHODS

For this retrospective study, we retrieved clinical data on 1130 patients with fragile hip fractures (67.2% female, mean age: 79.3 years) that underwent surgery at the Oulu University Hospital in 2013-2016. These data included the fracture risk assessment score (measured with the FRAX tool), the bone-mass T-score, laboratory values, ambulatory capacity, and the time of death.

RESULTS

In this population, 12.4% of patients sustained a second hip fracture. The predisposing factors for a second hip fracture were: female (p = 0.016), a high FRAX score (p = 0.020), and low physical capacity (p < 0.001). The vitamin D level recommended for treating osteoporosis (i.e., vitamin D > 75 nmol/l) was observed in only 24% of patients, and 42% of patients had ionized calcium levels below the reference range. According to the level of the cross-linked carboxy-terminal telopeptide of type I collagen (ICTP), 37% of patients did not have high bone turnover. We found a positive correlation between age and ICTP (p = 0.001). The risk of death was higher after the second hip fracture (p = 0.005), but we found no difference in age between patients with first and second hip fractures (p = 0.11).

CONCLUSION

After a hip fracture, a second hip fracture is a well-known risk. Nevertheless, we found that only one-third of patients with a second hip fracture had used anti-osteoporosis medication at any time previously. These findings suggested that second hip fractures were most likely to occur in patients with osteopenic T-score values, in women more often than men, and in patients with high FRAX scores and low ambulatory capacity.

Biomarkers for Prostate Cancer Bone Metastasis Detection and Prediction

Prostate cancer (PCa) causes deaths worldwide, ranking second after lung cancer. Bone metastasis (BM) frequently results from advanced PCa, affecting approximately 90% of patients, and it also often results in severe skeletal-related events. Traditional diagnostic methods for bone metastases, such as tissue biopsies and imaging, have substantial drawbacks. This article summarizes the significance of biomarkers in PCa accompanied with BM, including (1) bone formation markers like osteopontin (OPN), pro-collagen type I C-terminal pro-peptide (PICP), osteoprotegerin (OPG), pro-collagen type I N-terminal pro-peptide (PINP), alkaline phosphatase (ALP), and osteocalcin (OC); (2) bone resorption markers, including C-telopeptide of type I collagen (CTx), N-telopeptide of type I collagen (NTx), bone sialoprotein (BSP), tartrate-resistant acid phosphatase (TRACP), deoxypyridinoline (D-PYD), pyridoxine (PYD), and C-terminal pyridinoline cross-linked telopeptide of type I collagen (ICTP); (3) prostate-specific antigen (PSA); (4) neuroendocrine markers, such as chromogranin A (CgA), neuron-specific enolase (NSE), and pro-gastrin releasing peptide (ProGRP); (5) liquid biopsy markers, such as circulating tumor cells (CTCs), microRNA (miRNA), circulating tumor DNA (ctDNA), and cell-free DNA (cfDNA) and exosomes. In summary, some of these markers are already in widespread clinical use, while others still require further laboratory or clinical studies to validate their value for clinical application.

Clinical features and shared mechanisms of chronic gastritis and osteoporosis

Chronic gastritis (CG) and osteoporosis (OP) are common and occult diseases in the elderly and the relationship of these two diseases have been increasingly exposed. We aimed to explore the clinical characteristics and shared mechanisms of CG patients combined with OP. In the cross-sectional study, all participants were selected from BEYOND study. The CG patients were included and classified into two groups, namely OP group and non-OP group. Univariable and multivariable logistic regression methods were used to evaluate the influencing factors. Furthermore, CG and OP-related genes were obtained from Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were identified using the GEO2R tool and the Venny platform. Protein-protein interaction information was obtained by inputting the intersection targets into the STRING database. The PPI network was constructed by Cytoscape v3.6.0 software again, and the key genes were screened out according to the degree value. Gene function enrichment of DEGs was performed by Webgestalt online tool. One hundred and thirty CG patients were finally included in this study. Univariate correlation analysis showed that age, gender, BMI and coffee were the potential influencing factors for the comorbidity (P < 0.05). Multivariate Logistic regression model found that smoking history, serum PTH and serum β-CTX were positively correlated with OP in CG patients, while serum P1NP and eating fruit had an negative relationship with OP in CG patients. In studies of the shared mechanisms, a total of 76 intersection genes were identified between CG and OP, including CD163, CD14, CCR1, CYBB, CXCL10, SIGLEC1, LILRB2, IGSF6, MS4A6A and CCL8 as the core genes. The biological processes closely related to the occurrence and development of CG and OP mainly involved Ferroptosis, Toll-like receptor signaling pathway, Legionellosis and Chemokine signaling pathway. Our study firstly identified the possible associated factors with OP in the patients with CG, and mined the core genes and related pathways that could be used as biomarkers or potential therapeutic targets to reveal the shared mechanisms.

Insulin Resistance and Bone Metabolism Markers in Women with Polycystic Ovary Syndrome: A Cross-Sectional Study on Females from the Islamic University Medical Center

Background and Objectives: polycystic ovarian syndrome (PCOS) prevails in females in the 18-40-year-old age group and varies from 5-20% depending on the demographic and diagnostic standards. It is unknown how long passes between the onset of a specific symptom and the appearance of the disease. The three most significant characteristics of PCOS include irregular menstruation, a polycystic ovarian shape found by pelvic ultrasound, and hyperandrogenism, which could possibly delay menarche. This study's objective was to assess insulin resistance and bone bio-markers' metabolism-involved characteristics of females with PCOS. Materials and Methods: We present a cross-sectional study carried out on 100 female patients suffering from PCOS and 100 healthy female subjects as a control living in Saudi Arabia in the Al-Madinah Al-Munawara Region between May 2021 and March 2022. The age of the studied groups ranges from 20-40 years, and patients were categorized into three groups; group I (control, n = 100), group IIa (overweight or obese females with PCOS, n = 70), and group IIb (non-obese females with PCOS, n = 30). The diagnosis of PCOS was carried out as per Rotterdam criteria as recommended for adolescent and adult subjects. All the groups were subjected to physical examination, and anthropometric measures, biochemical parameters, endocrine activity, and clinical parameters were determined. The data obtained were computerized and analyzed statistically using the SPSS program for range, mean, and standard deviation. ANOVA test with post hoc Tukey test was applied to assess the pattern and variation among the test and control groups. Results: In the present study, age, waist circumstances, systolic blood pressure, and diastolic blood pressure were reported enhanced in the PCOS over the control group. Additionally, anthropometric measures were reported slightly upregulated in group IIa over group IIb (p < 0.001). Biochemical parameters including glucose, insulin incidence, and lipids were reported higher in the PCOS over the control group, where group IIa showed slightly increased values compared to group IIb (p < 0.001). On the contrary, PTH, Ca+2, and 25(OH)D levels were reported lower in the PCOS over the control group. However, in the control groups, a slight variation was reported as higher in group IIa compared to group II. In the study, PTH and 25(OH)D were found associated with bone metabolism; a lower level of PTH and 25 (OH) D is linked with a decline in bone density. Conclusions: Lower serum levels of PINP and osteocalcin along with the 25(OH)D were associated with the PCOS compared to the control group, imposing a higher risk of the syndrome. On the contrary, an elevated level of NTx in groups IIa and IIb over the control group was associated with insulin resistance and bone metabolism.

Factors associated with bone response to teriparatide in young postmenopausal women with osteoporosis

INTRODUCTION

To investigate the factors associated with changes in vertebral bone mineral density during teriparatide treatment.

MATERIALS AND METHODS

Single centre, longitudinal study involving 145 osteoporotic postmenopausal women treated with teriparatide. Clinical evaluation, bone mineral density (BMD) measurements assessment and laboratory analyses were performed at baseline then after 12 and 18 months of treatment. Bone non-response to treatment was defined as no significant increase in BMD at 18 months as compared to baseline.

RESULTS

Of the 145 women initially included, 109 completed the 18-month course of the treatment. 75% of them had a history of prior osteoporotic treatment. Baseline mean age was 60 ± 8 years. Mean baseline vertebral T-score was - 3.7 ± 0.7 and 83 (76%) women had suffered at least one vertebral fracture. At the end of treatment, 18 women (17%) were classified as non-responders. In the responder group (n = 91), vertebral BMD increased by 0.091 ± 0.04 g/cm2 (12.2 ± 5.3%). Clinical characteristics, baseline BMDs and the percentage of women previously treated with bisphosphonates as well as the duration of prior treatment did not significantly differ between the two groups of responders and non-responders. At baseline, non-responders had significant mean lower C-terminal fragment of type 1 collagen (CTX) values than responders (p < 0.01). Only baseline CTX values (r = 0.30 p < 0.01) were independently correlated to vertebral BMD changes during teriparatide treatment.

CONCLUSION

A minority of treated women had no vertebral densitometric gain after 18 months of teriparatide therapy. Low levels of baseline bone remodeling were the main factor associated with poor response to treatment.

Practical Considerations for the Clinical Application of Bone Turnover Markers in Osteoporosis

Bone turnover markers (BTMs) are released during the bone remodelling cycle and are measurable in blood or urine, reflecting bone remodelling rate. They have been useful in elucidating the pharmacodynamics and effectiveness of osteoporosis medication in clinical trials and are increasingly used in routine clinical management of osteoporosis, especially for monitoring therapy, in addition to their use in other metabolic bone disease such as Paget's disease of bone and osteomalacia. Serum β isomerised C-terminal telopeptide of type I collagen and pro-collagen I N-terminal propeptide have been designated as reference BTMs for use in osteoporosis. In addition, bone-specific isoenzyme of alkaline phosphatase (B-ALP) secreted by osteoblasts and tartrate-resistant acid phosphatase 5b (TRACP-5b) secreted by osteoclasts are also found to be specific markers of bone formation and resorption, respectively. The concentrations of the latter enzymes in blood measured by immunoassay provide reliable measures of bone turnover even in the presence of renal failure. B-ALP is recommended for use in the assessment of renal bone disease of chronic kidney disease, and TRACP-5b shows promise as a marker of bone resorption in that condition. BTMs in blood do not suffer from biological variation to the same extent as the older BTMs that were measured in urine. Appropriate patient preparation and sample handling are important in obtaining accurate measures of BTMs for clinical use. Reference change values and treatment targets have been determined for the reference BTMs for their use in monitoring osteoporosis treatment. Further ongoing studies will enhance their clinical applications.

Quantitative lateral flow immunoassay for rapid detection of procollagen type I N-terminal propeptide in the monitoring of osteoporosis treatment

Appropriate follow-up after treatment initiation in patients with osteoporosis is challenging. Serum biomarkers may offer more efficient monitoring of bone mineral density (BMD) than the currently used dual X-ray absorptiometry; however, significant changes in BMD often occur over at least 12 months. During teriparatide treatment for osteoporosis, monitoring with markers such as procollagen type I propeptide (PINP), which is derived from osteoblasts, can provide clinically useful information for disease management. However, rapid and cost-effective methods for detecting serum PINP are lacking, necessitating a point-of-care test (POCT) for enhanced follow-up efficiency in osteoporosis management. For the quantitative detection of PINP, we developed a high-sensitivity lateral flow immunoassay with a stacking pad (sLFIA). We established a calibration equation based on the test line/control line ratio obtained from our PINP sLFIA results of various nonspiked serum samples to calculate the PINP concentrations in 40 serum samples and compared the result with those obtained using a fully automated electrochemiluminescence immunoassay. PINP concentrations between these two methods exhibited excellent correlation (R = 0.991). In addition, we assessed the serum PINP concentrations of patients with osteoporosis treated with teriparatide. At the 3-month follow-up, their PINP levels were nearly twice as high as those at baseline, thus implying that our method can be used for osteoporosis treatment monitoring. Our findings thus indicate that the PINP sLFIA can serve as a POCT for monitoring medication response and managing osteoporosis.

Correlation Between Mean Amplitude of Glycemic Excursion and Bone Turnover Markers in Patients with Type 2 Diabetes: A Cross-Sectional Study

OBJECTIVE

The present study explores the relationship between glycemic excursion and bone turnover markers.

METHODS

A total of 250 patients with type 2 diabetes mellitus (T2DM) (142 female and 108 male patients) were enrolled in this study. All participants underwent 72 hours of continuous glycemic monitoring to evaluate the mean amplitude of glycemic excursions (MAGE) of each person. Bone turnover markers and other biochemical data were measured for each patient. Linear regression was performed to explore the relationship between bone turnover markers and glycemic excursion. A value of P < 0.05 was considered statistically significant.

RESULTS

MAGE was negatively correlated to N-terminal propeptide of type 1 collagen (P1NP) female: [odds ratios (95% confidence interval) (OR (95% CI)), -2.516 (-5.389, 0.356)]; male: [-2.895, (-6.521, -0.731)] and C-terminal telopeptide fragments of type-I collagen (β-CTX) female [-0.025, (-0.036, 0.005)]; male [-0.043, (-0.082, 0.003)]. MAGE was still negatively correlated with β-CTX female [-0.036, (-0.198, -0.030)]; male [-0.048, (-0.089, -0.007)] after adjusting for clinical data and biochemical indices.

CONCLUSION

An independent negative relationship between glycemic excursion and bone turnover markers in patients with T2DM was identified in this study.

Effect of Teriparatide on Bone Mineral Density and Bone Markers in Real-Life: Argentine Experience

PURPOSE

To evaluate the effect of teriparatide (TPTD) on bone mineral density (BMD) and bone markers under clinical practice conditions. To assess whether the results in real-life match those published in clinical trials.

METHODS

Cross-sectional study of postmenopausal women treated with TPTD for at least 12 months.

RESULTS

264 patients were included in the study. Main characteristics are as follows: age: 68.7 ± 10.2 years, previous fractures: 57.6%, and previously treated with antiresorptive (AR-prior): 79%. All bone turnover markers studied significantly increased after 6 months. CTX and BGP remained high up to 24 months, but total and bone alkaline phosphatase returned to basal values at month 18. There was a significant increase in lumbar spine (LS) BMD after 6 months (+6.2%), with a maximum peak at 24 months (+13%). Femoral neck (FN) and total hip (TH) BMD showed a significant increase later than LS (just at month 12), reaching a maximum peak at month 24 (FN + 7.9% and TH + 5.5%). A significant increase in LS BMD was found from month 6 to month 24 compared to basal in both AR-naïve, and AR-prior patients (+16.7% and +10.5%, respectively), without significant differences between the two groups. Comparable results were found in FN and TH BMD. Main conclusions. As reported in real-life clinical studies, treatment of osteoporotic postmenopausal women with TPTD induced a significant increase in bone turnover markers from month 6 onward and an increase in BMD from months 6-12 with continuous gain up to month 24. The real-life results of our study matched the results of randomized clinical trials. In addition, TPTD induced an increase in BMD, regardless of the previous use of AR.

Bone Turnover Markers: Basic Biology to Clinical Applications

Bone turnover markers (BTMs) are used widely, in both research and clinical practice. In the last 20 years, much experience has been gained in measurement and interpretation of these markers, which include commonly used bone formation markers bone alkaline phosphatase, osteocalcin, and procollagen I N-propeptide; and commonly used resorption markers serum C-telopeptides of type I collagen, urinary N-telopeptides of type I collagen and tartrate resistant acid phosphatase type 5b. BTMs are usually measured by enzyme-linked immunosorbent assay or automated immunoassay. Sources contributing to BTM variability include uncontrollable components (e.g., age, gender, ethnicity) and controllable components, particularly relating to collection conditions (e.g., fasting/feeding state, and timing relative to circadian rhythms, menstrual cycling, and exercise). Pregnancy, season, drugs, and recent fracture(s) can also affect BTMs. BTMs correlate with other methods of assessing bone turnover, such as bone biopsies and radiotracer kinetics; and can usefully contribute to diagnosis and management of several diseases such as osteoporosis, osteomalacia, Paget's disease, fibrous dysplasia, hypophosphatasia, primary hyperparathyroidism, and chronic kidney disease-mineral bone disorder.

Current use of bone turnover markers in the management of osteoporosis

The adult bone is continuously being remodelled to repair microdamage, preserve bone strength and mechanical competence as well as maintain calcium homeostasis. Bone turnover markers are products of osteoblasts (bone formation markers) and osteoclasts (bone resorption markers) providing a dynamic assessment of remodelling (turnover). Resorption-specific bone turnover markers are typically degradation products of bone collagen molecules (N- [NTX] and C-telopeptide cross-linked type 1 collagen [CTX]), which are released into the circulation and excreted in urine; or enzymatic activities reflecting osteoclastic resorption, tartrate-resistant acid phosphatase [TRACP]. Formation-specific bone turnover markers embrace different osteoblastic activities: type 1 collagen synthesis (Procollagen type I N- propeptide [PINP]), osteoblast enzymes (bone-specific alkaline phosphatase [BALP]), or bone matrix proteins [osteocalcin]. Among individuals not receiving osteoporosis treatment, resorption and formation markers are tightly linked and highly correlated (r= 0.6-0.8). Significant biological variability was reported in the past, but these issues have been greatly improved with automated assays and attention to pre-analytical and analytical factors that are known to influence bone turnover marker levels. Bone turnover markers are not useful in the diagnosis of osteoporosis, the individual prediction of bone loss, fracture, or rare complications, or in the selection of pharmacological treatment. Despite remaining issues with reference intervals and assays harmonization, bone turnover markers have proven to be useful in elucidating the pharmacodynamics and effectiveness of osteoporosis medications in clinical trials. As an alternative to BMD testing, BTMs may be useful to monitor osteoporosis therapies.

Effect on bone anabolic markers of daily cheese intake with and without vitamin K2: a randomised clinical trial

Background

Daily intake of 57 g Jarlsberg cheese has been shown to increase the total serum osteocalcin (tOC). Is this a general cheese effect or specific for Jarlsberg containing vitamin K₂ and 1,4-dihydroxy-2naphtoic acid (DHNA)?

Methods

66 healthy female volunteers (HV) were recruited. By skewed randomisation (3:2), 41 HV were allocated to daily intake of 57 g Jarlsberg (J-group) and 25-50 g Camembert (C-group) in 6 weeks. After 6 weeks the C-group was switched to Jarlsberg. The study duration was 12 weeks with clinical investigations every 6 weeks. The main variables were procollagen type 1 N-terminal propeptide (PINP), tOC, carboxylated osteocalcin (cOC) and the osteocalcin ratio (R_O) defined as the ratio between cOC and undercarboxylated osteocalcin (ucOC). Serum cross-linked C-telopeptide type I collagen (CTX), vitamin K₂, lipids and clinical chemistry were used as secondary variables.

Results

PINP, tOC, cOC, R_O and vitamin K₂ increased significantly (p<0.01) after 6 weeks in the J-group. PINP remained unchanged in the C-group. The other variables decreased slightly in the C-group but increased significantly (p≤0.05) after switching to Jarlsberg. No CTX-changes detected in neither of the groups.Serum lipids increased slightly in both groups. Switching to Jarlsberg, total cholesterol and low-density lipoprotein-cholesterol were significantly reduced (p≤0.05). Glycated haemoglobin (HbA1c), Ca⁺⁺ and Mg⁺⁺ were significantly reduced in the J-group, but unchanged in the C-group. Switching to Jarlsberg, HbA1c and Ca⁺⁺ decreased significantly.

Conclusion

The effect of daily Jarlsberg intake on increased s-osteocalcin level is not a general cheese effect. Jarlsberg contain vitamin K₂ and DHNA which increases PINP, tOC, cOC and R_O and decreases Ca⁺⁺, Mg⁺⁺ and HbA1c. These effects reflect increased bone anabolism and a possible reduced risk of adverse metabolic outcomes.

Trial registration number

NCT04189796.

Value of Biochemical Indexes of Bone Metabolism in Predicting Osteoporotic Lumbar Fractures

Objective

To investigate the value of bone metabolism indexes such as type I procollagen N-terminal propeptide (P1NP), 25-hydroxyvitamin D (25(OH)D), osteocalcin (OSTEOC), and parathyroid hormone (PTH) in predicting osteoporotic lumbar fractures.

Methods

120 female patients with osteoporosis treated in our hospital were selected as research objects. There were 76 cases in the fracture group and 44 cases in the nonfracture group. The relationship between the levels of P1NP, 25(OH)D, OSTEOC, and PTH and the incidence of osteoporotic lumbar fractures were detected and compared between the two groups. The predictive value of biochemical indexes of bone metabolism in patients with osteoporosis was analyzed by ROC curve.

Results

The levels of P1NP and PTH in the fracture group were significantly higher than those in the nonfracture group, while 25(OH)D and OSTEOC levels were lower than those in the nonfracture group. Moreover, the levels of P1NP, 25(OH)D, OSTEOC, and PTH are important factors affecting the pathogenesis of osteoporosis. The area under the curve (AUC) of fracture in patients with osteoporosis predicted by the combination of P1NP, 25(OH)D, OSTEOC, and PTH levels was 0.886, which was greater than the AUC predicted by each index (0.796, 0.753, 0.670, and 0.824). The best sensitivity and specificity of comprehensive prediction of each index were 78.95% and 79.10%, respectively.

Conclusion

The abnormal changes of P1NP, 25(OH)D, OSTEOC, and PTH in female patients with osteoporotic lumbar fracture are closely related to the occurrence of the disease. The combination of these indicators has relatively significant application value in predicting the occurrence of fracture, which is helpful to formulate and guide relevant preventive measures for female patients with osteoporotic lumbar fracture and improve the prognosis.

[Effects of 275 nm and 310 nm ultraviolet irradiation on bone metabolism in ovariectomized osteoporotic rats]

OBJECTIVE

To investigate the effect of 275 nm and 310 nm ultraviolet irradiation on ovariectomized rats' bone metabolism.

METHODS

Twenty four 3-month-old female Sprague-Dawley (SD) rat were randomly divided into control group, sham operated group, 275 nm ultraviolet (UV) irradiation group and 310 nm UV irradiation group. Each group contained 6 rats. The rats in the two irradiation groups were treated with bilateral ovariectomy. The rats in sham operated group received sham operation (They were given the same back incision and a bit of par-ovarian fat were removed). Control group received no disposition. About 24 weeks after operation, all the rats received detailed bone mineral density (BMD) detection again. Detection regions include cervical vertebra, lumbar vertebra, proximal femur, mid femur and distal femur. Next, osteopenia rats in 275 nm irradiation group were UV irradiated 275 nm with fixed illumination intensity (15 μW/cm2) everyday for 16 weeks. The osteopenia rats in 310 nm irradiation group were UV irradiated 310 nm with fixed illumination intensity (15 μW/cm2) everyday for 16 weeks. The backs of the rats were shaved regularly as irradiation area (6 cm×8 cm). After 16-week irradiation, all the rats' BMD of cervical vertebra, lumbar vertebra, proximal femur, mid femur and distal femur were measured. At the end of the trial, all the rats' blood specimens were obtained and serum 25(OH)D, procollagen type Ⅰ N-peptide (PINP) and osteocalcin (OC) were measured.

RESULTS

Compared with control group [(238.78±26.74) mg/cm3], the BMD of the whole body were significantly lower in 275 nm [(193.34±13.28) mg/cm3] and 310 nm [(191.19±18.48) mg/cm3] irradiation groups (P=0.002, P=0.001). There were no significant difference between sham operated group [(227.20±14.32) mg/cm3] and control group. After 16-week ultraviolet irradiation, the BMD of the whole body were significantly increased in 275 nm [(193.34±13.28) mg/cm3 vs. (221.68±25.52) mg/cm3, P=0.005] and 310 nm groups [(191.19±18.48) mg/cm3 vs. (267.48±20.54) mg/cm3, P < 0.001] after corresponding irradiation. The BMD of the four body regions (lumbar vertebra, proximal femur, mid femur and distal femur) had significantly increased after irradiation in 275 nm irradiation group. For 310 nm irradiation group, the BMD in cervical vertebra, lumbar vertebra, proximal femur, mid femur and distal femur also had increased significantly after 310 nm ultraviolet irradiation. The concentration of serum 25(OH)D and OC was higher in 275 nm irradiation group than in control group [(46.78±5.59) μg/L vs. (21.32±6.65) μg/L, P=0.002;(2.05±0.53) U/L vs. (1.32±0.07) U/L, P=0.022]. Compared with the control, the concentration of serum 25(OH)D [(58.05±12.74) μg/L], OC [(2.04±0.53) U/L] and PINP [(176.16±24.18) U/L] was significantly higher (P < 0.001, P=0.015, P=0.005) in 310 nm irradiation group. However, there were no significantly difference between sham operated group and the control.

CONCLUSION

Both 275 nm and 310 nm ultraviolet could improve rats' vitamin D synthesis. Both 275 nm and 310 nm ultraviolet could improve osteopenia rats' bone condition. The irradiation of 310 nm might be more effective on bone condition improvement.

[Effects of 275 nm and 310 nm ultraviolet irradiation on bone metabolism in ovariectomized osteoporotic rats]

OBJECTIVE

To investigate the effect of 275 nm and 310 nm ultraviolet irradiation on ovariectomized rats' bone metabolism.

METHODS

Twenty four 3-month-old female Sprague-Dawley (SD) rat were randomly divided into control group, sham operated group, 275 nm ultraviolet (UV) irradiation group and 310 nm UV irradiation group. Each group contained 6 rats. The rats in the two irradiation groups were treated with bilateral ovariectomy. The rats in sham operated group received sham operation (They were given the same back incision and a bit of par-ovarian fat were removed). Control group received no disposition. About 24 weeks after operation, all the rats received detailed bone mineral density (BMD) detection again. Detection regions include cervical vertebra, lumbar vertebra, proximal femur, mid femur and distal femur. Next, osteopenia rats in 275 nm irradiation group were UV irradiated 275 nm with fixed illumination intensity (15 μW/cm²) everyday for 16 weeks. The osteopenia rats in 310 nm irradiation group were UV irradiated 310 nm with fixed illumination intensity (15 μW/cm²) everyday for 16 weeks. The backs of the rats were shaved regularly as irradiation area (6 cm×8 cm). After 16-week irradiation, all the rats' BMD of cervical vertebra, lumbar vertebra, proximal femur, mid femur and distal femur were measured. At the end of the trial, all the rats' blood specimens were obtained and serum 25(OH)D, procollagen type Ⅰ N-peptide (PINP) and osteocalcin (OC) were measured.

RESULTS

Compared with control group [(238.78±26.74) mg/cm³], the BMD of the whole body were significantly lower in 275 nm [(193.34±13.28) mg/cm³] and 310 nm [(191.19±18.48) mg/cm³] irradiation groups (P=0.002, P=0.001). There were no significant difference between sham operated group [(227.20±14.32) mg/cm³] and control group. After 16-week ultraviolet irradiation, the BMD of the whole body were significantly increased in 275 nm [(193.34±13.28) mg/cm³ vs. (221.68±25.52) mg/cm³, P=0.005] and 310 nm groups [(191.19±18.48) mg/cm³ vs. (267.48±20.54) mg/cm³, P < 0.001] after corresponding irradiation. The BMD of the four body regions (lumbar vertebra, proximal femur, mid femur and distal femur) had significantly increased after irradiation in 275 nm irradiation group. For 310 nm irradiation group, the BMD in cervical vertebra, lumbar vertebra, proximal femur, mid femur and distal femur also had increased significantly after 310 nm ultraviolet irradiation. The concentration of serum 25(OH)D and OC was higher in 275 nm irradiation group than in control group [(46.78±5.59) μg/L vs. (21.32±6.65) μg/L, P=0.002;(2.05±0.53) U/L vs. (1.32±0.07) U/L, P=0.022]. Compared with the control, the concentration of serum 25(OH)D [(58.05±12.74) μg/L], OC [(2.04±0.53) U/L] and PINP [(176.16±24.18) U/L] was significantly higher (P < 0.001, P=0.015, P=0.005) in 310 nm irradiation group. However, there were no significantly difference between sham operated group and the control.

CONCLUSION

Both 275 nm and 310 nm ultraviolet could improve rats' vitamin D synthesis. Both 275 nm and 310 nm ultraviolet could improve osteopenia rats' bone condition. The irradiation of 310 nm might be more effective on bone condition improvement.

[Effect of bone anabolic therapy on bone remodeling and bone density in geriatric patients with osteoporosis and falling syndrome]

BACKGROUND

Older adults with severe osteoporosis are the most vulnerable group of geriatric patients. They are shown the purpose of anti-osteoporotic therapy, which should be effective and safe. Teriparatide showed a decrease in the risk of fractures, an increase in BMD. In Russia, the use of teriparatide in the geriatric population is extremely scarce.

AIM

assess clinical course, bone metabolism parameters and efficacy of bone-anabolic therapy in elderly and senile patients with severe osteoporosis and falls.

MATERIALS AND METHODS

The longitudinal prospective study included 100 patients 60 years and older with severe osteoporosis who had one or more falls within the last year. All patients were prescribed calcium and vitamin D preparations and bone-anabolic therapy (teriparatide 20 mg daily subcutaneously). The duration of follow-up was 24 months and included 3 visits: screening, at 12 and 24 months. The effectiveness of bone-anabolic therapy was carried out on the basis of assessing the frequency of new fractures, reduction of pain, changes in BMD according to X-ray densitometry, dynamics of bone metabolism markers.

RESULTS

All patients had severe osteoporosis and aggravated comorbidity status, suffered a fall within the last year, and also low-energy fractures in the past. One in three patients had a vertebral fracture, one in five had a proximal femoral fracture. Prior to the start of the study, 61 patients received antiosteoporotic therapy. During the follow-up, 4 patients died, 96 patients completed the study. Against the background of teriparatide therapy, a decrease in the number of new cases of low-energy fractures and the number of patients with chronic pain was obtained. An increase in BMD was noted in the lumbar spine after 24 months and in the femoral neck after 12 months. There was no negative dynamics of the BMD. Also after 12 months, an increase in P1NP and C-terminal telopeptide of collagen type 1 was noted, after 24 months - osteocalcin and C-terminal telopeptide.

CONCLUSION

The use of teriparatide can be recommended as an effective intervention to treat severe osteoporosis in geriatric patients with falls.

Plasma EBF1 as a Novel Biomarker for Postmenopausal Osteoporosis

Postmenopausal osteoporosis (OPO) is one of the most common types of primary osteoporosis. There is currently lack of a plasma biomarker for sensitive and early diagnosis of OPO. Here we aimed to explore the potential of early B cell factor 1 (EBF1) as a new plasma biomarker of OPO. Quantitative real-time PCR was used to measure the plasma EBF1 levels. Absorptiometry markers, such as lumbar spine (LS) bone mineral density (BMD) and LS T score were obtained after X-ray scans. Biochemical analyses used to measure osteopontin (OPN), β-isomerized C-terminal telopeptides and total N-terminal procollagen of type-I collagen levels of patients with osteopenia (OPE, n = 81), osteoporosis (OPO, n = 98) as well as healthy subjects (NC, n = 110). Quantitative real-time PCR was used to measure the plasma levels of PAX5 and GSTP1, which are target genes of EBF1. EBF1 was downregulated in OPO patients. Levels of EBF1 were positively correlated to clinicopathological characteristics, including LS BMD and LS T scores, and negatively correlated to OPN and total N-terminal procollagen of type-I collagen levels. Increased PAX5 and GSTP1 levels also demonstrated strong correlations with higher EBF1, LS BMD and LS T score. Anti-osteoporotic treatment resulted in significant upregulation of EBF1, PAX5 and GSTP1 at 6 mo after treatment. Our study suggests that plasma EBF1 is a potential biomarker for diagnosing and assessing treatment outcome of OPO.

Folic Acid Attenuates High-Fat Diet-Induced Osteoporosis Through the AMPK Signaling Pathway

Objective: Obesity caused by a high-fat diet (HFD) will expand adipose tissue and cause chronic low-grade systemic inflammation, leading to osteoporosis. Folic acid (FA) is a water-soluble vitamin that plays an essential role in regulating blood lipids and antioxidants. However, the effects and underlying mechanisms of FA in osteoporosis induced by an HFD remain poorly understood. This study aimed to investigate the effect of FA on bone health by using HFD-induced osteoporosis mice. Materials and Methods: Mice were fed a normal diet, HFD or an HFD supplemented with FA (20 μg/ml in drinking water) for 16 weeks. Throughout the 16 weeks study period, the rats were weighed once every week. GTT, ITT and lipid indexes were detected to evaluate the effects of FA on lipid metabolism in the HFD-fed mice. Morphological and structural changes of the femur and tibial bone were observed using micro-CT, HE staining and bone conversion parameters. The expression of MDA, SOD and inflammatory factors were detected to evaluate the effects of FA on oxidative stress and inflammatory response in the HFD-fed mice. Quantitative real-time PCR and Western blot (WB) were used to investigate the AMPK signaling pathway. Results: After the intervention of FA, the body fat rate of obese mice was reduced, and related metabolic disorders such as insulin resistance, hyperlipidemia, and systemic inflammation were alleviated. In correlation with those modifications, FA attenuated bone loss and improved bone microarchitecture, accompanied the number of osteoclasts and adipocytes decreased. Furthermore, FA promoted the phosphorylation of AMPK, thereby promoting the expression of Carnitine palmitoyltransferase 1 (CPT1), nuclear factor erythroid-2 related factor 2 (Nrf2) and antioxidant enzymes. Conclusion: These findings suggest that FA may modulate lipid metabolism and oxidative stress responses activating the AMPK signaling pathway, thereby alleviating HFD-induced osteoporosis. The results from our study provide experimental evidence to prevent HFD-induced osteoporosis.

Treatment of osteoporosis with teriparatide: The Slovenian experience

The aim of this study was to investigate the characteristics of postmenopausal women prescribed with teriparatide in Slovenia, during the first decade after its approval, and the predictors of bone mineral density (BMD) improvement with treatment. We retrospectively studied postmenopausal osteoporotic patients prescribed with teriparatide at tertiary center from 2006 to 2015. BMD was measured at standard sites by DXA at baseline, after 12 and 24 months. 25-hydroxyvitamin D and procollagen type I N-terminal propeptide (PINP) were measured at the same time-points. The inclusion criteria were met by 188 women (aged 71 years on average), 151 (80.3%) with postmenopausal and 37 (19.7%) with glucocorticoid-induced osteoporosis. Everyone had at least one fracture, 159 (84.6%) had ≥2 fractures, with vertebral fractures in 172 patients (91.5%). All patients had been previously on antiresorptives for 8.6 years on average. The average BMD change at lumbar spine, total hip, and femoral neck was +5.0%, −1.1%, and +0.3% after 24 months of treatment, respectively. Higher baseline PINP was associated with higher BMD increase at all sites after the first 12 months. Teriparatide was prescribed mostly to elderly women with severe osteoporosis who had sustained two or more fractures despite long-term antiresorptive therapy. Baseline PINP might predict initial BMD increase with teriparatide.

Bone turnover marker responses to sleep restriction and weekend recovery sleep

BACKGROUND

Prior data demonstrated three weeks of sleep restriction and concurrent circadian disruption uncoupled bone turnover markers (BTMs), indicating decreased bone formation and no change or increased bone resorption. The effect of insufficient sleep with or without ad libitum weekend recovery sleep on BTMs is unknown.

METHODS

BTMs were measured in stored serum from 20 healthy adults randomized to one of three study groups consisting of a control group (N = 3 men; 9 h/night) or one of two nocturnal sleep restriction groups in an inpatient laboratory environment. One Sleep Restriction group ("SR"; N = 9; 4 women) had 5 h sleep opportunity per night for nine nights. The other sleep restriction group had an opportunity for ad libitum Weekend Recovery sleep ("WR"; N = 8; 4 women) after four nights of 5 h sleep opportunity per night. Food intake was energy balanced at baseline and ad libitum thereafter. Fasted morning BTM levels and hourly 24 h melatonin levels were obtained on study days 3 (baseline), 5 (after 1 night of sleep restriction for WR and SR), and 11 (after a sleep restricted workweek with weekend recovery sleep in WR or 7 nights of sleep restriction in SR). Linear mixed-effects modeling was used to examine the effect of study duration (e.g., change over time), study condition, age, and sex on BTMs. Pearson correlations were used to determine associations between changes in BTMs and changes in weight and morning circadian misalignment (i.e., duration of high melatonin levels after wake time).

RESULTS

There was no significant difference between the three study groups in change over time (p ≥ 0.4 for interaction between assigned group and time for all BTMs), adjusted for age and sex. There was no significant change in N-terminal propeptide of procollagen type I (P1NP), osteocalcin, or C-telopeptide of type I collagen (CTX) from baseline to day 11 (all p ≥ 0.3). In women <25 years old, there was a non-significant decline in P1NP from day 3 to day 5 (= -15.74 ± 7.80 ng/mL; p = 0.06). Change in weight and morning circadian misalignment from baseline to day 11 were correlated with statistically non-significant changes in BTMs (all p ≤ 0.05).

CONCLUSION

In this small secondary analysis, we showed that nine nights of prescribed sleep restriction with or without weekend recovery sleep and ad libitum food intake did not alter BTMs. It is possible that age, sex, weight change and morning circadian misalignment modify the effects of sleep restriction on bone metabolism.

[Changes in the related indicators of bone formation and bone resorption in severely burned rats]

Objective: To observe the changes in the related indicators of bone formation and bone resorption in severely burned rats. Methods: The experimental research method was adopted. Thirty female Sprague-Dawley rats aged 6 to 8 weeks were divided into sham injury group, 12% total body surface area (TBSA) full-thickness burn group, and 24%TBSA full-thickness burn group according to the random number table, with 10 rats in each group. The rats were treated on the back correspondingly, after which, the burned rats were rehydrated by intraperitoneal injection according to the Parkland formula, and the wound was coated with 20 g/L iodophor until wound healing. On post injury day (PID) 28, the tibia tissue of rats in each group was collected. The new bone tissue and the number of osteoclasts were observed after staining with Masson and tartrate-resistant acid phosphatase, respectively. The abdominal aortic blood of rats in each group was harvested for serum preparation. The bone metabolism indexes of serum calcium ion and phosphorus ion concentration were determined by the methyl thymol blue colorimetric method and phosphomolybdic acid method, respectively. The serum levels of bone formation marker of aminoterminal propeptide of type 1 procollagen (P1NP) and bone resorption marker of beta-carboxy-terminated peptide of type Ⅰ collagen (β-CTX) were determined by enzyme-linked immunosorbent assay. The first lumbar spine tissue of rats in each group was collected, and the mRNA expression levels of osteoprotegerin, receptor activator of nuclear factor-κB ligand (RANKL), tumor necrosis factor receptor-associated factor 6 (TRAF-6), nuclear factor of activated T cell 1 (NFATC1), c-Fos, and c-Src were detected by real-time fluorescent quantitative reverse transcription polymerase chain reaction. Data were statistically analyzed with one-way analysis of variance, Bonferroni method, Welch test, Games-Howell test, Kruskal-Wallis test, Mann-Whitney U test, and Bonferroni correction. Results: On PID 28, compared with that in sham injury group, the formation of new bone tissue in the tibia tissue of rats in the two burn groups was decreased, and the larger the burn area, the more obvious the decrease. The numbers of osteoclasts in the tibia tissue of rats in the two burn groups were similar, both significantly more than the number in sham injury group. On PID 28, the serum calcium ion concentration and serum level of β-CTX of rats in the three groups were similar (P>0.05). The serum phosphorus ion concentration of rats in 24%TBSA full-thickness burn group was significantly higher than that in 12%TBSA full-thickness burn group (P<0.05), and the serum phosphorus ion concentrations in the two burn groups were significantly higher than the concentration in sham injury group (P<0.01). The serum level of P1NP of rats in 24%TBSA full-thickness burn group was significantly lower than that in sham injury group (P<0.01). On PID 28, the mRNA expression levels of osteoprotegerin in the first lumbar spine tissue of rats in sham injury group, 12%TBSA full-thickness burn group, and 24%TBSA full-thickness burn group were 1.01±0.20, 1.71±0.83, and 2.24±0.51, respectively, and that in 24%TBSA full-thickness burn group was significantly higher than that in sham injury group (P<0.01). The mRNA expression level of RANKL in the first lumbar spine tissue of rats in 24%TBSA full-thickness burn group was 1.31±0.17, which was significantly higher than 1.00±0.14 in sham injury group and 0.97±0.10 in 12%TBSA full-thickness burn group (P<0.01). The mRNA expression levels of TRAF-6, NFATC1 (Z=3.141, 3.782), and c-Src in the first lumbar tissue of rats in 12%TBSA full-thickness burn group and 24%TBSA full-thickness burn group and the mRNA expression level of c-Fos in the first lumbar tissue of rats in 12%TBSA full-thickness burn group were significantly higher than those in sham injury group (P<0.05 or P<0.01). The mRNA expression levels of c-Fos and c-Src in the first lumbar spine tissue of rats in 12%TBSA full-thickness burn group were significantly higher than those in 24%TBSA full-thickness burn group (P<0.01). Conclusions: Severe burns can cause a decrease in the generation of new bone tissue, an increase in the number of osteoclasts and the serum phosphorus ion concentration, and a decrease in the serum level of P1NP in rats. The level of osteoprotegerin, RANKL, TRAF-6, NFATC1, c-Fos, and c-Src in bone tissue showed an increasing trend while the level of NFATC1, c-Fos, and c-Src showed a decreasing trend with the increase of burn area.

Effect of Vitamin D-Enriched Gouda-Type Cheese Consumption on Biochemical Markers of Bone Metabolism in Postmenopausal Women in Greece

Considering the role of bone metabolism in understanding the pathogenesis of osteoporosis, the aim of the present study was to examine the effects of vitamin D-enriched cheese on the serum concentrations of the parathyroid hormone (PTH) and certain bone remodeling biomarkers in postmenopausal women in Greece. In a randomised, controlled dietary intervention, 79 postmenopausal women (55–75 years old) were randomly allocated either to a control (CG: n = 39) or an intervention group (IG: n = 40), consuming 60 g of either non-enriched or vitamin D3-enriched Gouda-type cheese (5.7 μg of vitamin D3), respectively, daily and for eight weeks during the winter. The serum concentrations of 25-hydroxy vitamin D (25(OH)D), PTH, bone formation (i.e., osteocalcin, P1NP) and bone resorption (i.e., TRAP-5b) biomarkers were measured. Consumption of the vitamin D-enriched cheese led to higher serum 25(OH)D concentrations of 23.4 ± 6.39 (p = 0.022) and 13.4 ± 1.35 (p < 0.001) nmol/L in vitamin D-insufficient women being at menopause for less and more than 5 years, respectively. In vitamin D-insufficient women that were less than 5 years at menopause, consumption of vitamin D-enriched cheese was also associated with lower serum PTH (Beta −0.63 ± 1.11; p < 0.001) and TRAP-5b (Beta −0.65 ± 0.23; p = 0.004) levels at follow-up, compared with the CG. The present study showed that daily intake of 5.7 μg of vitamin D through enriched cheese increased serum 25(OH)D concentrations, prevented PTH increase and reduced bone resorption in vitamin D-insufficient early postmenopausal women, thus reflecting a potential food-based solution for reducing the risk of bone loss occurring after menopause.

Effects of resveratrol supplementation on bone quality: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

The results from clinical trials have revealed that the effects of resveratrol supplementation on bone mineral density (BMD) and bone biomarkers are inconsistent. Our objective was to determine the effects of resveratrol supplementation on BMD and serum bone biomarkers.

METHODS

PubMed, Cochrane library, EMBASE, Web of science and Scopus were searched up to August 24, 2020. Two reviewers independently performed the articles search and screen according to defined selection criteria. The study quality of the randomized controlled trials (RCTs) was evaluated with the Cochrane scoring system. Heterogeneity among studies was examined by Cochrane Q test. Retrieved data were pooled after mean differences (MD) were computed between two groups for BMD and serum biomarkers. Subgroup analyses were performed to evaluate a potential difference in terms of dose of resveratrol and intervention duration. Sensitivity analysis was executed by omitting studies with imputed values in order to evaluate the influence of these studies on the overall results.

RESULTS

Ten eligible studies involving 698 subjects were included in this meta-analysis with 401 participants receiving resveratrol and 297 receiving placebo. Supplementation of resveratrol had no statistically significant effects on areal bone mineral density (aBMD) at lumbar spine (MD: -0.02, 95% CI: - 0.05, 0.01, p = 0.26, I² = 6%), total hip BMD (MD: -0.01, 95% CI: - 0.04, 0.02, p = 0.65, I² = 0%), and whole body BMD (MD: 0.00, 95% CI: - 0.02, 0.02, p = 0.74, I² = 0%). Supplementation of resveratrol also did not result in significant change in bone serum markers, including serum alkaline phosphatase (ALP), bone alkaline phosphatase (BAP), osteocalcin (OCN), procollagen I N-terminal propeptide (PINP), C-terminal telopeptide of type I collagen (CTX) and parathyroid hormone (PTH). Subgroup analysis showed the effect of resveratrol supplementation on BMD and serum bone markers were similar in trails of different doses, intervention duration, and pathological conditions of the participants.

CONCLUSION

Resveratrol supplementation did not show any significant effect on BMD or serum bone markers with the current evidence. Further investigation with more well-organized multicentre randomized trial is warranted.

The Indian Society for Bone and Mineral Research (ISBMR) position statement for the diagnosis and treatment of osteoporosis in adults

The Indian Society for Bone and Mineral Research (ISBMR) has herein drafted clinical practice guidelines for the diagnosis and management of osteoporosis for the people of India. Implementation of the position statement in clinical practice is expected to improve the overall care of patients with osteoporosis in India.

PURPOSE

In India, osteoporosis is a major public health problem. However, in the absence of any robust regional guidelines, the screening, treatment, and follow-up of patients with osteoporosis are lagging behind in the country.

METHODS

The Indian Society for Bone and Mineral Research (ISBMR), which is a multidisciplinary group of physicians, researchers, dietitians, and epidemiologists and who study bone and related tissues, in their annual meeting, drafted the guidelines for the diagnosis and management of osteoporosis that would be appropriate in a resource constraint setting like India.

RESULTS

Diagnosis of osteoporosis can be made in a patient with minimal trauma fracture without the aid of any other diagnostic tools. In others, bone mineral density measured by dual-energy X-ray absorptiometry remains the modality of choice. Data indicates that osteoporotic fractures occur at an earlier age in Indians than in the West; hence, screening for osteoporosis should begin at an earlier age. FRAX can be used for fracture risk estimation; however, it may underestimate the risk of future fractures in our population and still needs validation. Maintaining optimum serum 25-hydroxyvitamin D levels is essential, which, in most cases, would require regular vitamin D supplementation. Pharmacotherapy should be guided by the presence/absence of vertebral/hip fractures or the severity of risk based on clinical factors, although bisphosphonates remain the first choice in most cases. Regular follow-up is essential to ensure adherence and response to therapy.

CONCLUSIONS

Implementation of the position statement in clinical practice is expected to improve the overall care of patients with osteoporosis in India.

Apelin/APJ system: A novel therapeutic target for locomotor system diseases

Apelin is an endogenous ligand of G protein-coupled receptor APJ. Apelin/APJ system is widely expressed in abundant tissues, especially bone, joint and muscle tissue. This review focus on the effects of apelin/APJ system on locomotor system. An increasing number of evidence suggests that apelin/APJ system plays a crucial role in many physiological and pathological processes of locomotor system. Physiologically, apelin/APJ system promotes bone formation, muscle metabolism and skeletal muscle production. Pathologically, apelin/APJ system exacerbates osteoarthritis pathogenesis, whereas it alleviates osteoporosis. Besides, the level of apelin expression is regulated by different training modes, including continuous aerobic exercise, high-intensity interval training and resistance exercises. More importantly, exercise-induced apelin may be a potent pharmacological agent for the treatment of diseases and the regulation of physiological processes. Considering the pleiotropic effects of apelin on locomotor system, apelin/APJ system may be an important therapeutic target for locomotor system diseases.

An emerging role of Prevotella histicola on estrogen deficiency-induced bone loss through the gut microbiota-bone axis in postmenopausal women and in ovariectomized mice

BACKGROUND

The gut microbiota (GM)-bone axis has emerged as a crucial mediator of bone homeostasis. Estrogen deficiency-induced bone loss is closely associated with an altered GM. However, the underlying mechanisms remain unclear.

OBJECTIVES

We sought to explore the putative effects of GM on estrogen deficiency-induced bone loss and determine a potential mechanism.

METHODS

Fecal samples collected from postmenopausal women with osteoporosis (PMO) and with normal bone mass (PMN) were examined by 16S ribosomal RNA (rRNA) gene sequencing and analysis. Prevotella histicola, a typical species of Prevotella, was orally given to female C57BL6/J mice after ovariectomy [ovariectomized (OVX)]. The primary outcomes were changes in bone microstructures as measured by micro-computed tomography scanning and bone histomorphometry analysis. Secondary outcomes included changes in osteoclast activity, the expression of osteoclastogenic cytokines, and gut permeability, which were measured by ELISA, qRT-PCR, western blot, and immunofluorescence.

RESULTS

As demonstrated through 16S rRNA gene sequencing and analysis, the GM in the PMO group featured a significantly decreased proportion of the genus Prevotella in comparison with that in the PMN group (∼60%, P < 0.05). In animal experiments, P. histicola-treated OVX mice maintained a relatively higher bone volume than OVX controls. Mechanistically, the protective effects of P. histicola on bone mass were found to be associated with its modulation of gut permeability as well as its inhibitory effects on osteoclast activity which function by attenuating osteoclastogenic cytokine expression.

CONCLUSIONS

The GM diversity and composition between the PMN and PMO groups were significantly different. In particular, the proportion of the genus Prevotella was notably higher in the PMN group, demonstrating its potential bone-protective effects on osteoporosis. Further animal study using osteoporotic mice showed P. histicola could prevent estrogen deficiency-induced bone loss through the GM-bone axis. Thus, P. histicola may serve as a therapeutic agent or target for osteoporosis treatment.