Bone Turnover Markers in the Diagnosis and Monitoring of Metabolic Bone Disease

Comparison of microwave ablation and parathyroidectomy for treating severe secondary hyperparathyroidism

Objective

This study compared the efficacy of microwave ablation (MWA) and parathyroidectomy (PTX) in the treatment of secondary hyperparathyroidism (SHPT) and evaluated the improvement of bone metabolic markers (BMMs) and bone mineral density (BMD).

Materials and methods

Eligible patients with SHPT treated between January 2019 and August 2022 were enrolled in the study and were divided into two groups: MWA and PTX. Outcome measures included the treatment success rate, percentage of patients whose intact parathyroid hormone (iPTH) concentration was within the target range, serum calcium (Ca), phosphorus (P), alkaline phosphatase (ALP), osteocalcin (OC), C-terminal cross-linked telopeptide of type I collagen (β-CXT), and BMD. Data on the procedure time, intraoperative blood loss volume, length and cost of hospitalization, incidence of postoperative complications, and recurrence rates were analyzed.

Results

A total of 107 patients with SHPT-48 in the MWA group and 59 in the PTX group- were included in the study. There were no significant differences in baseline data between the two groups (p>0.05). At the final follow-up, both therapies decreased iPTH, Ca, P, ALP, OC, and β-CXT levels and increased BMD (p<0.05). Nonetheless, the decrease in iPTH, ALP, OC, and β-CXT was more pronounced 6 and 12 months after PTX (p<0.05). The percentage of patients whose iPTH level was within the target range was significantly higher in the MWA group (p<0.05). The incidence of severe hypocalcemia was significantly lower in the MWA group (p<0.05).

Conclusion

MWA can improve BMMs and BMD, and is a minimally invasive approach with great potential for treating patients with SHPT who cannot tolerate PTX.

Elevated baseline CTX levels predict enhanced therapeutic efficacy of zoledronic acid in augmenting lumbar spine bone mineral density among Chinese osteoporosis patients

This study examined the link between baseline CTX levels and zoledronic acid's effectiveness in boosting bone density in osteoporosis patients. Among 472 Chinese patients, higher initial CTX levels correlated with greater lumbar spine bone density improvement after treatment. However, no such correlation was found for hip or femoral neck bones. This suggests CTX levels may aid in treatment selection for lumbar spine, though further research is needed. The findings have clinical implications for optimizing osteoporosis treatment.

PURPOSE

To elucidate the correlation between baseline CTX levels and the therapeutic efficacy of zoledronic acid in augmenting bone mineral density (BMD) among individuals with osteoporosis.

METHODS

This study studied patients diagnosed with primary osteoporosis who were hospitalized at least twice and received annual zoledronic acid therapy. Patients were stratified into three groups based on their initial CTX levels prior to zoledronic acid administration. ANOVA was employed to compare BMD alterations across the groups. Generalized estimating equations (GEE) were utilized to analyze the relationship between baseline CTX levels and subsequent BMD changes post-zoledronic acid treatment. Statistical analyses were conducted using SPSS version 26.0.

RESULTS

A total of 472 patients were evaluated and categorized into three cohorts according to their initial CTX levels, arranged in ascending order. Notably, group 3, characterized by the highest initial CTX levels, demonstrated a significantly more pronounced increase in lumbar spine BMD compared to the other two groups. Specifically, when group 1 served as the reference, group 3 exhibited a 0.4-unit elevation in lumbar spine T-score. Conversely, no discernible relationship was observed between baseline CTX levels and BMD changes in the hip or femoral neck following zoledronic acid treatment.

CONCLUSIONS

Our findings among a Chinese population indicate that elevated CTX levels, particularly exceeding 0.480 ng/ml, are notably associated with enhanced therapeutic efficacy of zoledronic acid in boosting lumbar spine BMD. However, this correlation appears less robust with respect to improvements in hip and femoral neck BMD.

Circulating collagen type I fragments as specific biomarkers of cardiovascular outcome risk: Where are the opportunities?

Collagen type I (COL1) is the most abundant protein in the human body and is a main component in the extracellular matrix. The COL1 structure vastly influences normal tissue homeostasis and changes in the matrix drive progression in multiple diseases. Cardiovascular diseases (CVD) are the leading cause of mortality and morbidity in many Western countries; alterations in the extracellular matrix turnover processes, including COL1, are known to influence the pathophysiological processes leading to CVD outcome. Peptides reflecting COL1 formation and degradation have been established and explored for over two decades in CVD. This review aims to combine and assess the evidence for using COL1-derived circulating peptides as biomarkers in CVD. Secondly, the review identifies existing pitfalls, and evaluates future opportunities for improving the technical characteristics and performance of the biomarkers for implementation in the clinical setting.

The crucial role of beta-catenin in the osteoprotective effect of semaglutide in an ovariectomized rat model of osteoporosis

Postmenopausal osteoporosis is a common chronic medical illness resulting from an imbalance between bone resorption and bone formation along with microarchitecture degeneration attributed to estrogen deficiency and often accompanied by other medical conditions such as weight gain, depression, and insomnia. Semaglutide (SEM) is a recently introduced GLP-1 receptor agonist (GLP-1RA) for the treatment of obesity and type 2 diabetes mellitus by mitigating insulin resistance. It has been discovered that the beneficial effects of GLP-1 are associated with alterations in lipolysis, adipogenesis, and anti-inflammatory processes. GLP-1 analogs transmit signals directly to adipose tissue. Mesenchymal stem cells (MSCs) are multidisciplinary cells that originate from bone marrow, migrate to injury sites, and promote bone regeneration. MSCs can differentiate into osteoblasts, adipose cells, and cartilage cells. Our aim is to investigate the role of semaglutide on bone formation and the Wnt signaling pathway. Osteoporosis was induced in female rats by ovariectomy, and the ovariectomized rats were treated with alendronate as standard treatment with a dose of 3 mg/kg orally and semaglutide with two doses (150 mcg/kg and 300 mcg/kg) S.C. for 10 successive weeks. Semaglutide ameliorates bone detrimental changes induced by ovariectomy. It improves bone microarchitecture and preserves bone mineral content. Semaglutide ameliorates ovariectomy-induced osteoporosis and increases the expression of β-catenin, leading to increased bone formation and halted receptor activator of nuclear factor kappa-Β ligand (RANKL's) activation. Semaglutide can be used as a potential prophylactic and therapeutic drug against osteoporosis, possibly by activating Wnt signaling and decreasing bone resorption.

Exon junction complexes regulate osteoclast-induced bone resorption by influencing the NFATc1 m6A distribution through the "shield effect"

BACKGROUND

The distribution of the m6A methylation modification on the transcriptome is highly regionally selective and is mainly concentrated in abnormally long exons and stop codons. However, in-depth research on the selective mechanism of m6A methylation is still lacking.

METHODS

In this research, meRIP sequencing, mRNA sequencing, meRIP, luciferase reporter assays and CRISPR/Cas9 conditional knockout mice were used to elucidate the distribution characteristics of NFATc1 m6A.

RESULTS

METTL14 controls osteoclast-mediated bone resorption by means of the methylation (4249 A) of the NFATc1 gene during osteoclast differentiation. Exon junction complexes (EJCs) selectively protect the m6A methylation sites of the NFATc1 gene. When the methylation sites are located within short exon fragments (50-200 nt), EJCs prevent their hypermethylation and degradation through the "shield effect"; when the methylation sites are located in the 3' UTR region or long exon fragments (greater than 300 nt), the "shield effect" disappears. Downstream, YTHDF2 induced the degradation of hypermethylation NFATc1 transcripts without site restriction.

CONCLUSIONS

EJCs act as "shields" to regulate the m6A region selectivity of the NFATc1 gene, thereby determining the characteristics of m6A distribution in the gene. Importantly, EJCs can raise the level of m6A methylation of NFATc1 and degrade its mRNA, thereby inhibiting osteoclast differentiation and preserving bone mass. These results will be helpful for identifying potential molecular targets for osteoporosis treatment.

KEY POINTS

METTL14 controls osteoclast-mediated bone resorption by means of the methylation (4249 A) of the NFATc1 gene during osteoclast differentiation. Exon junction complexes (EJCs) protect the remaining methylation sites of the NFATc1 gene (located in the inner exon fragment of 50-200 nt) from hypermethylation and degradation. The "shield effect" disappears when the exon fragment is extended to 300 nt. Downstream, YTHDF2 induced the degradation of hypermethylation NFATc1 transcripts without site restriction.

Effect of GLP-1 receptor agonists on bone mineral density, bone metabolism markers, and fracture risk in type 2 diabetes: a systematic review and meta-analysis

AIM

To systematically assess randomized controlled trials that evaluated the effect of glucagon-like peptide-1 (GLP-1) receptor agonists on fracture incidence, bone mineral density, and bone metabolism markers in individuals with type 2 diabetes.

METHODS

From database setup to March 21, 2024, a search was conducted across nine Chinese and English databases. The Cochrane Risk of Bias Tool was applied to assess potential bias. Data analysis was performed using RevMan 5.3 and Stata 14.0. Subgroup analysis and meta regression were employed to explore sources of heterogeneity, and publication bias was evaluated using funnel plots and Egger's test.

RESULTS

Twenty-five studies were included. The results of the meta-analysis indicated that GLP-1 receptor agonist was not significantly associated with an increased risk of fracture (RR = 0.80; 95% CI 0.47 to 1.36; P = 0.41). Additionally, improvement in lumbar spine BMD (MD = 0.07 g/cm2, 95% CI 0.06 to 0.09, P < 0.00001), hip neck BMD (MD = 0.05 g/cm2, 95% CI 0.03 to 0.08, P = 0.0001) and total hip BMD (MD = 0.06 g/cm2, 95% CI 0.04 to 0.07, P < 0.00001) was superior to the control group. Similarly, GLP-1 receptor agonists significantly improved P1NP (SMD = 0.33, 95% CI 0.07 to 0.59, P = 0.01), OC (MD = 1.46 ug/L, 95% CI 1.10 to 1.83, P < 0.00001), 25-OH-D (SMD = 0.45, 95% CI 0.06 to 0.83, P = 0.02), and b-ALP (MD = 0.91ug/L, 95% CI 0.19 to 1.63, P = 0.01) while reducing β-CTX (SMD = - 0.34, 95% CI - 0.54 to - 0.14, P = 0.001). There was no significant impact on other bone metabolism markers, including N-MID-OT (SMD = 0.43, 95% CI 0.01 to 0.86, P = 0.05), ALP (SMD = - 0.00, 95% CI: - 0.25 to 0.25, P = 0.98), Calcium (MD = 0.00 mmol/L, 95% CI - 0.04 to 0.04, P = 0.94) and Phosphate (MD = 0.02 mmol/L, 95% CI - 0.04 to 0.07, P = 0.57).

CONCLUSION

This meta-analysis demonstrated no significant effect of GLP-1 receptor agonists on elevated fracture risk. There was a statistically significant improvement in BMD and certain bone turnover markers (β-CTX, P1NP, OC, b-ALP, and 25-OH-D). However, due to some limitations, further high-quality clinical studies with sufficient follow-up time are needed to draw more definitive conclusions.

Effects of Isoflavone Interventions on Bone Metabolism in Perimenopausal and Postmenopausal Women: An Umbrella Review of Meta-Analyses of Randomized Controlled Trials

OBJECTIVE

Previous meta-analyses have investigated the effects of isoflavones on bone metabolism in perimenopausal or postmenopausal women. However, there were still conflicting results. Thereby, this umbrella review assessed the existing meta-analysis evidence of the effects of isoflavone interventions on bone metabolism in perimenopausal and postmenopausal women.

METHODS

This study was conducted following the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. From the inception until August 24, 2023, PubMed, Embase, Cochrane, and Web of Science databases were searched to identify meta-analyses of randomized controlled trials. The outcomes included bone mineral densities (BMDs), and bone turnover markers of osteocalcin, bone-specific alkaline phosphatase, pyridinoline, deoxypyridinoline, Procollagen Type 1 N-Terminal Propeptide, and C-telopeptide of Type 1 Collagen. The random-effects model was used to recalculate the extracted effect sizes. Mean difference (MD) was used as a summary effect measure.

RESULTS

Ten meta-analyses of randomized controlled trials were included. The isoflavone intervention was associated with increased BMDs in lumbar spine (MD: 11.50 mg/cm2, 95% confidence interval (CI): 6.46 to 16.55), femoral neck (MD: 2.03%, 95% CI: 0.57 to 3.50), and top hip (MD: 0.31%, 95% CI: 0.03 to 0.59) in perimenopausal and postmenopausal women.

CONCLUSION

Our findings indicate that isoflavone interventions have the potential to improve BMD at different bone sites, including the lumbar spine, femoral neck, and total hip in perimenopausal and postmenopausal women. Isoflavone may be considered a complementary option in the bone loss of perimenopausal and postmenopausal women.

Hormonal Contraception and Bone Metabolism: Emerging Evidence from a Systematic Review and Meta-Analysis of Studies on Post-Pubertal and Reproductive-Age Women

BACKGROUND/OBJECTIVES

This study aims to assess the effects of combined hormonal contraceptives (CHCs) on bone metabolism markers. It primarily measures osteocalcin and additionally examines other bone health markers, seeking to determine their responses to estrogen-progestogen treatments.

METHODS

This study involved a comprehensive evaluation of the pertinent literature and a meta-analysis explicitly conducted on data describing women of reproductive age. The analysis encompassed accessible papers ranging to December 2024 (i.e., those listed in PubMed/Medline, Embase, Scopus, the Cochrane Database, International Clinical Trials Registry, and ClinicalTrials.gov). We examined published randomized controlled trials (RCTs) and prospective studies. The quality of the studies was assessed using the Cochrane tool for RCTs and the Newcastle-Ottawa Scale for prospective studies. The selected indicators for primary and secondary outcomes were ascertained by standardized mean change (SMC), displaying the difference between conditions before and after treatment. Trends were evaluated using meta-regressions.

RESULTS

Ultimately, 34 articles out of 1924 identified items met the inclusion criteria, covering 33 unique studies. In EE/E4 combinations, osteocalcin dropped significantly (SMC -0.54 (CI.95 -0.64/-0.43) and -0.43 (CI.95 -0.76/-0.10)). Similar effects were observed for other bone-formation and reabsorption markers, with less significant reductions observed in E2-containing CHC (e.g., alkaline phosphatase (bone) EE combinations, SMC -0.39 (CI.95 -0.67/-0.11); P1NP E2 combination, 0.12 (CI.95 -0.10/0.33); and EE combinations, -0.55 (CI.95 -0.83/-0.26)). The reduction patterns also exhibited differences according to the women's age (e.g., osteocalcin in EE combinations ≤21, SMC -0.63 (CI.95 -0.77/-0.49) and >21, SMC -0.42 (CI.95 -0.61/-0.24); alkaline phosphatase (bone) EE combinations ≤21, SMC -0.55 (CI.95 -0.86/-0.24) and >21, SMC -0.06 (CI.95 -0.47/0.35)). This analysis found that CHC maintains or reduces bone turnover in childbearing women, with effects varying by age and hormone combination. Moreover, bone-formation and reabsorption markers correlated positively to pro-androgenic progestins (p < 0.05). Thus, estrogen-progestogen combinations reduce bone turnover less when weak estrogens and a pro-androgenic or neutral progestin are present.

CONCLUSIONS

This study found that CHCs reduce bone turnover, with natural estrogens and androgenic progestins appearing to be more beneficial than EE and anti-androgenic types. These findings would potentially influence decisions relevant to CHC prescriptions during a woman's reproductive phases, emphasizing the need for additional research to tailor CHC usage to bone health.

Serum Pentosidine in Relation to Obesity in Patients with Type 2 Diabetes and Healthy Controls

Pentosidine (PEN), a surrogate marker of advanced glycation end-product formation, reflects increased non-enzymatic cross-linking in bone collagen, which is thought to be an important determinant of bone fragility in type 2 diabetes mellitus (T2DM). We aimed to investigate serum concentrations of PEN in patients with T2DM and controls without T2DM and to examine its relationship with bone parameters and metabolic state such as glycaemic control, insulin resistance and body weight. In a cross-sectional study-design, data from postmenopausal women and men with T2DM (n = 110) and controls without T2DM (n = 111) were evaluated. Serum PEN was measured using an ELISA-based assay (CSB-E09415h, Cusabio). In addition, biochemical markers of glucose metabolism and bone turnover markers were measured. Bone mineral density (BMD) was assessed by dual-energy X-ray absorptiometry. After adjustment for age, gender and body mass index (BMI), serum PEN was significantly higher in patients with T2DM compared to controls (p = 0.02) and most prominently in women with T2DM (p = 0.09). We found a strong association of serum PEN concentrations with BMI in the entire study population (R = 0.43, p < 0.001) as well as in patients with T2DM (R = 0.28, p < 0.01). While bone turnover markers were significantly decreased, and BMD increased in patients with T2DM, only weak or no associations were observed between these skeletal surrogate markers and serum PEN. We conclude that serum PEN is strongly associated with BMI with highest levels in obese women with T2DM. Adjustment for patient's weight is needed when evaluating serum PEN levels in patients with T2DM.Clinical Trial Information: NCT02551315.

Moderate-to-vigorous physical activity modulates the association between serum 25-hydroxyvitamin D and bone stiffness in European children and adolescents

It remains unclear how serum 25-hydroxyvitamin D (25(OH)D) concentrations relate to childhood bone health. We hypothesized that 25(OH)D was inversely associated with bone turnover biomarkers and positively associated with bone stiffness. Cross-sectional analyses were performed using data from participants (2-15-year-old, 51% boys) from the Identification and Prevention of Dietary- and Lifestyle-induced Health Effects in Children and Infants Study (IDEFICS)/I.Family cohort, comprising 3,638 serum 25(OH)D measurements collected in 2007-2008 and 2012-2013 across eight European countries. A biomarker of bone formation (serum osteocalcin), a biomarker of bone resorption (serum C-terminal telopeptides of type I collagen [CTx]), and stiffness index measured using calcaneal quantitative ultrasound were considered outcomes. Linear mixed-effects models were used to adjust for confounders (i.e., age, sex, parental education, time spent in sports club, dairy products consumption, sedentary behavior, height and weight z-scores), the cluster effect of country and repeated measurements. Interactions of calcium intake, moderate-to-vigorous physical activity (MVPA) and weight status with 25(OH)D on outcomes were tested. Only 1 in 3 participants reached the sufficient 25(OH) D concentration of 20 ng/mL. Sufficient 25(OH)D was associated with higher stiffness index if participants had MVPA ≥60 min/day (β = 12.14, P < .05). Moreover, 25(OH)D was inversely associated with CTx (β = -7.09, P < .05); this association was positive but not statistically significant among primary school children living with overweight/obesity. No interaction was observed for calcium intake. In conclusion, serum 25(OH)D and CTx were inversely associated. MVPA interacted with the positive association between 25(OH)D and bone stiffness, highlighting the importance of promoting MVPA guidelines in future vitamin D and bone health interventions.

Bone Health ECHO Case Report: Is it Paget's Disease?

A 54-year-old woman was referred by her rheumatologist for evaluation of an elevated serum alkaline phosphatase (ALP) in the setting of polyarthritis. The metabolic work-up was significant for an elevated bone fraction of alkaline phosphatase isoenzymes, and high bone turnover markers, including fasting C- telopeptide (CTX). A diagnosis of Paget's disease of bone (PDB) was considered. A whole-body nuclear bone scan showed diffuse increased uptake in the calvarium, suggestive of PDB, with no other localizing areas of increased uptake. Skull X-rays show mild sclerosis and medullary expansion of the posterior parietal bones and occiput, interpreted by the radiologist as unlikely to be PDB with a high level of uncertainty. Bone density testing with dual-energy X-ray absorptiometry showed low bone mass (osteopenia) with fracture probability that was below the treatment threshold. The case was presented and discussed on Bone Health ECHO, a virtual community of practice with the aim of enhancing global capacity to deliver best practice skeletal health care. The results of the discussion are presented here.

Reference Intervals (RIs) of the Bone Turnover Markers (BTMs) in Children and Adolescents: A Proposal for Effective Use

BACKGROUND/OBJECTIVES

Bone turnover markers (BTMs) can provide information on the bone growth of apparently healthy children and adolescents or useful results in the diagnosis and monitoring of the disease condition, comparing them with appropriate reference intervals (RIs). The aim of this study was to establish the RI for the BTM [specific bone alkaline phosphatase (BALP), carboxy-terminal cross-linked collagen type I telopeptide (CTX), N-terminal propeptide pro-collagen type I (PINP), osteocalcin (OC), resistant to acid tartrate phosphatase isoform 5b (TRAcP-5b)] on serum samples from children and adolescents.

METHOD

202 samples from children and adolescents (ages 1-18 years) (51.48% male), considered apparently healthy. The biomarker was analyzed on automatic immunometric equipment (TGSTA Technogenetics) and the IDS-iSYS automated system kits The RI of the studied parameters was calculated according to CLSI Guideline C28-A3 with stratification by age and sex. Evaluation of the distribution of values and the meaning of the biomarker concentrations were used to calculate general and specific RI for an age group.

RESULTS

BTM concentrations vary with pubertal growth. The pattern of change differs for each bone marker. General and age-specific RI were calculated: 1-14 years, 15-18 years for BALP and CTX; 1-13 years, 14-18 years for Oc and PINP and 1-12 years, 13-18 years for TRAcP.

DISCUSSION AND CONCLUSIONS

Concentrations for biomarker studied vary with age and gender. The proof of concentrations with insignificant changes until puberty led to identification of two groups of RI relating to the covariables (age and sex) for each biomarker.

Effects of exercise on bone mass and bone metabolism in adolescents: a systematic review and meta-analysis

Objective

Meta-analysis was used to evaluate the effects of an exercise intervention on bone mineral content (BMC), bone mineral density (BMD), and bone metabolism in adolescents.

Methods

A systematic search of PubMed, Embase, Cochrane Library, and Web of Science for RCTs on "exercise, adolescents, BMD, bone metabolism" up to 10 September 2024. Included RCTs focused on effects of exercise on BMC, BMD, and bone metabolism in 10-19 years old, with physical activity as exercise group and daily living/primal exercise as control group. Outcome metrics included lumbar spine, femoral neck, whole body BMC and BMD, bone alkaline phosphatase (BALP), procollagen type 1N-terminal propeptide (PINP), osteocalcin (OC), and type I collagen carboxy-terminal peptide (CTX). Exclusion criteria included duplicates, non-RCTs, non-adolescent studies, and non-compliance with indicators. Meta-analyses were performed using RevMan 5.4, and quality assessed by Cochrane's tool. Effect sizes were estimated using standardized mean differences (SMDs) and 95% confidence intervals (CIs), and heterogeneity was assessed using the I 2 statistic to determine fixed or random effects models.

Results

Fifteen articles with a total of 723 subjects were included. The meta-analysis showed that, compared to the control group, (i) exercise was effective in increasing adolescents' overall BMC (SMD = 0.16, 95% CI: 0.06-0.27, p = 0.003) and BMD (SMD = 0.26, 95% CI: 0.13-0.40, p = 0.0001). (ii) Subgroup analyses showed that exercise significantly increased adolescents' lumbar spine BMC (SMD = 0.17, 95% CI: 0.01-0.34, p = 0.04), femoral neck BMC (SMD = 0.23, 95% CI: 0.05-0.42, p = 0.01), lumbar spine BMD (SMD = 0.34, 95% CI: 0.12-0.56, p = 0.003) and femoral neck BMD (SMD = 0.31, 95% CI: 0.09-0.53, p = 0.007), whereas there was no statistically significant effect on whole body BMC and BMD (p > 0.05). (iii) Exercise increased BALP, and decreased PINP, OC and CTX in adolescents. but none of the differences between the exercise groups and the control group were significant (p > 0.05).

Conclusion

Exercise is effective in improving overall BMC and BMD in adolescents and elevating BMC and BMD of the lumbar spine and femoral neck. Due to the limitation of the number and quality of the included studies, the above conclusions are yet to be validated by more high-quality empirical studies.

Systematic Review Registration

https://www.crd.york.ac.uk/, identifier CRD42024593399.

Hypoglycemic agents and bone health; an umbrella systematic review of the clinical trials' meta-analysis studies

BACKGROUND

No clear consensus exists regarding the safest anti-diabetic drugs with the least adverse events on bone health. This umbrella systematic review therefore aims to assess the published meta-analysis studies of randomized controlled trials (RCTs) conducted in this field.

METHODS

All relevant meta-analysis studies of RCTs assessing the effects of anti-diabetic agents on bone health in patients with diabetes mellitus (DM) were collected in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). English articles published until 15 March 2023 were collected through the search of Cochrane Library, Scopus, ISI Web of Sciences, PubMed, and Embase using the terms "Diabetes mellitus", "anti-diabetic drugs", "Bone biomarker", "Bone fracture, "Bone mineral density" and their equivalents. The methodological and evidence quality assessments were performed for all included studies.

RESULTS

From among 2220 potentially eligible studies, 71 meta-analyses on diabetic patients were included. Sodium-glucose cotransporter-2 inhibitors (SGLT-is) showed no or equivalent effect on the risk of fracture. Dipeptidyl peptidase-4 inhibitors (DPP-4is) and Glucagon-like peptide-1 receptor agonists (GLP-1Ras) were reported to have controversial effects on bone fracture, with some RCTs pointing out the bone protective effects of certain members of these two medication classes. Thiazolidinediones (TZDs) were linked with increased fracture risk as well as higher concentrations of C-terminal telopeptide of type I collagen (CTx), a bone resorption marker.

CONCLUSION

The present systematic umbrella review observed varied results on the association between the use of anti-diabetic drugs and DM-related fracture risk. The clinical efficacy of various anti-diabetic drugs, therefore, should be weighed against their risks and benefits in each patient.

Challenges and Perspectives Regarding the Determination of Gingival Crevicular Fluid Biomarkers During Orthodontic Treatment: A Narrative Review

Background: Changes in the positions of teeth occur during orthodontic treatment due to the application of forces that cause restructuring of the periodontal tissue. In the last decade, substantial research has been conducted to detect different biomarkers in the gingival crevicular fluid (GCF) to obtain a better assessment of the periodontal status. Aim: The purpose of this review is to describe how the levels of certain biomarkers from the gingival fluid change during tissue remodeling throughout orthodontic treatment. Materials and methods: To carry out the purpose of this research, electronic databases were searched using specific keywords, leading to 387 articles, out of which 19 were used in writing this narrative review. A sampling period of the last 10 years was used in selecting the articles. Results: The results highlight that the origin of the gingival crevicular fluid is at the gingival blood vessels' plexus. GCF has a complex composition with differences depending on the periodontal status and the tissue restructuring which takes place in the periodontium. The levels of inflammatory mediators, enzymes, and metabolic products of tissue remodeling in GCF change during orthodontic treatment. Being aware of their specific role, they can provide valuable information about bone remodeling during orthodontic tooth movement. Conclusions: By determining the biomarkers in GCF, as an investigative method, clinicians could easily monitor the orthodontic tooth movement, and, subsequently, the treatment period could be shortened and the adverse effects associated with it could be avoided.

Contribution of bone turnover markers (BTMs) and vitamin D to bone health in Iranian elderly women

Purpose

While only a few postmenopausal women exhibit biochemical signs of hypovitaminosis D, it has been shown that vitamin D insufficiency has detrimental effects on the overall skeleton mineralization, bone turnover rate, and may be a significant risk factor for osteoporosis and fracture. We evaluated the concurrent effect of Vitamin D levels and biochemical markers of bone turnover on bone health of postmenopausal women.

Methods

The present study was conducted within the framework of the Bushehr Elderly Health (BEH) program, a population-based prospective cohort study being conducted in Bushehr, a southern province of Iran. In summary, 400 persons from participants of the second stage were selected; serum bone turnover markers (bone-specific alkaline phosphatase (bALP), amino-terminal procollagen propeptides of type I collagen (P1NP), osteocalcin (OC), tartrate-resistant acid phosphatase isoenzyme 5b (TRAP)) and vitamin D were measured. Vitamin D deficiency was defined as serum 25(OH) D below 20 ng/ml, and Bone health was considered in terms of Osteoporosis and degraded bone microarchitecture.

Results

The number of partially or significantly degraded microstructure based on TBS was higher than the number of osteoporotic women based on BMD. Women with higher CTX levels were more prone to being degraded microarchitecture. Although we couldn't find any association between vitamin D deficiency and bone health, when we considered the vitamin D levels in univariable modelling, the effect of it was significant.

Conclusions

In this study, only CTX was found to be significantly correlated with TBS while BMD was associated with CTX, OC, and TRAP.

Metabolic shifts in ratio of ucOcn to cOcn toward bone resorption contribute to age-dependent bone loss in male mice

The study of the senile osteoporosis in men still lags significantly behind that in women. The changes of protein molecule levels and their relationships with bone loss remain poorly understood. In the present study, we used C57BL/6J male mice at ages from 3 to 24 mo to delineate the mechanisms of aging effects on bone loss. We used the microcomputed tomography, mechanical testing, histomorphometry assays, and detection of serum levels of undercarboxylated osteocalcin (ucOcn) and carboxylated osteocalcin (cOcn) to assess bone mass changes and their relationships with the ratios of ucOcn-to-cOcn in mice from different age groups. The results showed that mouse trabecular bone mass reduced gradually with age, whereas cortical bone loss and mechanical property changes mostly occurred in advanced age. Our findings further demonstrated that the increase in osteoclast activity and the decrease in osteoblast function were significantly corelated with blood levels of ucOcn and cOcn, respectively. The dynamic metabolic changes of ucOcn to cOcn ratio were correlated with age-dependent bone loss in mice. In summary, metabolic shifts in the ratio of ucOcn to cOcn toward bone resorption from young adult to elderly mice contribute to the pathogenesis of age-related bone loss. Simultaneously monitoring blood ratios of ucOcn-to-cOcn may be useful to predict the status of bone mass in vivo.NEW & NOTEWORTHY To our knowledge, our finding in this study shows for the first time that metabolic shifts in ratio of ucOcn to cOcn toward bone resorption are markedly correlated with age-dependent bone loss in male mice. These findings for the effects of aging on bone loss will assist in studying the pathogenesis of human type II osteoporosis.

Bone Mineral Density, C-Terminal Telopeptide of Type I Collagen, and Osteocalcin as Monitoring Parameters of Bone Remodeling in CML Patients Undergoing Imatinib Therapy: A Basic Science and Clinical Review

BACKGROUND

Chronic myeloid leukemia (CML) is one of the most commonly found types of myeloproliferative neoplasms, characterized by increased proliferation of granulocytic cells without losing their differentiation ability. Imatinib, a tyrosine kinase inhibitor (TKI), can be effectively used as therapy for CML. However, Imatinib can affect bone turnover thus having clinical implications on the bones of CML patients undergoing long-term Imatinib therapy. However, parameters that can accurately describe the bone condition in CML patients receiving Imatinib still need further study. A combination of imaging techniques such as bone mineral density (BMD) and bone turnover activity markers such as C-terminal telopeptide of type I collagen (CTX-1) and osteocalcin has the potential to be used as monitoring parameters for bone density abnormalities in CML patients receiving Imatinib.

OBJECTIVES

This article explains the rationale for using BMD, CTX-1, and osteocalcin as monitoring parameters of bone remodeling in CML patients receiving Imatinib.

RESULTS

First, the physiological process of bone turnover will be explained. Then, we describe the role of tyrosine kinase in bone metabolism. Next, the impact of Imatinib on BMD, CTX-1, and osteocalcin will be explained.

CONCLUSION

The assessment of bone health of CML patients on Imatinib should include both BMD tests and bone turnover marker assays such as CTX-1 and osteocalcin.

Society for endocrinology guideline for understanding, diagnosing and treating female hypogonadism

Female hypogonadism (FH) is a relatively common endocrine disorder in women of premenopausal age, but there are significant uncertainties and wide variation in its management. Most current guidelines are monospecialty and only address premature ovarian insufficiency (POI); some allude to management in very brief and general terms, and most rely upon the extrapolation of evidence from the studies relating to physiological estrogen deficiency in postmenopausal women. The Society for Endocrinology commissioned new guidance to provide all care providers with a multidisciplinary perspective on managing patients with all forms of FH. It has been compiled using expertise from Endocrinology, Primary Care, Gynaecology and Reproductive Health practices, with contributions from expert patients and a patient support group, to help clinicians best manage FH resulting from both POI and hypothalamo-pituitary disorders, whether organic or functional.

Elevations of N-Terminal Mid-Fragment of Osteocalcin and Cystatin C Levels are Associated with Disorders of Glycolipid Metabolism and Abnormal Bone Metabolism in Patients with Type 2 Diabetes Mellitus Complicated with Osteoporosis

ABSTRACT

Type 2 diabetes mellitus (T2DM) patients always develop osteoporosis (OP). We examined correlations of N-terminal mid-fragment of osteocalcin (N-MID) and cystatin C (Cys C) levels with glycolipid metabolism, bone metabolism markers, and bone mineral density (BMD) in elderly T2DM-OP patients. Grouping was performed as per whether T2DM patients developed OP (OP group) or not (N-OP group). N-MID and Cys C were measured using enzyme-linked immunosorbent assay, with correlations with glycolipid metabolism, bone metabolism indicators, and BMD analyzed using Pearson's correlation coefficient. Elderly T2DM-OP patients showed elevated disease duration, age, body mass index, glycated hemoglobin (HbA1c), Homer's insulin resistance (HOMA-IR), total cholesterol (TC), beta-carboxy-terminal crosslinked telopeptide of type 1 collagen (β-CTX), tartrate-resistant acid phosphatase 5b (TRACP-5b), N-MID and Cys C levels, and reduced high-density lipoprotein cholesterol (HDL-C), bone alkaline phosphatase (B-ALP), aminoterminal propeptide of type I procollagen (PINP), carboxyterminal propeptide of type I procollagen (PICP), BMD, and calcium supplementation. N-MID and Cys C were positively correlated with HbA1c, HOMA-IR, TC, β-CTX, and TRACP-5b and negatively with HDL-C, B-ALP, PINP, PICP, and BMD in elderly T2DM-OP patients. Conclusively, the abnormal elevations of serum N-MID and Cys C were associated with glycolipid metabolism disorder, abnormal bone metabolism, and decreased BMD in elderly T2DM-OP patients.

From Genomics to Metabolomics: Molecular Insights into Osteoporosis for Enhanced Diagnostic and Therapeutic Approaches

Osteoporosis (OP) is a prevalent skeletal disorder characterized by decreased bone mineral density (BMD) and increased fracture risk. The advancements in omics technologies-genomics, transcriptomics, proteomics, and metabolomics-have provided significant insights into the molecular mechanisms driving OP. These technologies offer critical perspectives on genetic predispositions, gene expression regulation, protein signatures, and metabolic alterations, enabling the identification of novel biomarkers for diagnosis and therapeutic targets. This review underscores the potential of these multi-omics approaches to bridge the gap between basic research and clinical applications, paving the way for precision medicine in OP management. By integrating these technologies, researchers can contribute to improved diagnostics, preventative strategies, and treatments for patients suffering from OP and related conditions.

Poor Bone Mineral Density Is Associated With Increased Risk of Urological Bone Metastases

OBJECTIVE

To investigate whether a diagnosis of precancer poor bone mineral density (PBMD) is associated with higher risk of urological cancer bone metastasis.

METHODS

The PearlDiver Database was utilized to conduct a retrospective, propensity-matched cohort analysis of adult patients diagnosed with kidney, bladder, prostate, and testicular cancer with and without a prior diagnosis of PBMD, defined as osteopenia or osteoporosis. Unadjusted and adjusted odds ratios (OR) and 95% confidence intervals are used to compare the rate of newly diagnosed bone metastases between 6months and 3years of the initial cancer diagnosis between the experimental and control cohorts.

RESULTS

Among 685,066 patients with urological cancers, precancer PBMD was associated with increased odds of bone metastasis at various time periods (1week, 6months, 1, 2, and 3years). The strongest association was appreciated within 1week of cancer diagnosis (kidney: adjusted odds ratio [aOR], 2.37, P <.001; bladder: [aOR], 2.37, P <.001; prostate: [aOR], 2.84, P <.001; testicular: [aOR], 4.45, P <.001). Bisphosphonates were associated with reduced risk of kidney ([aOR], 0.46, P <.001), bladder ([aOR], 0.61, P <.001), and prostate ([aOR], 0.66, P <.001) cancer bone metastasis.

CONCLUSION

Our findings suggest urology patients with PBMD may be predisposed to forming bone metastases as well as presenting with metastatic disease at time of cancer diagnosis. As such, further studies are needed to elucidate whether PBMD plays a role in bone tropism and whether bone health pertains to prolonging bone-free metastasis.

Causal Association of Telomere Length and Loss of Bone: a Directional Mendelian Randomization Study of Multi-Outcomes

This study employed a genome-wide association study (GWAS) to investigate the relationship between telomere length and marginal bone loss (MBL), a marker of bone health and aging. Telomere length, a biological indicator of aging, was analyzed alongside several serum markers of bone loss. Following a screen for appropriate instrumental variables, telomere length was designated as the exposure variable. We conducted the main analysis using random-effects inverse variance weighting (IVW) and supplemented it with MR Egger, weighted median, simple mode, and weighted mode analyses, employing a total of five methods. Positive outcomes underwent scrutiny through heterogeneity analysis, horizontal multiplicity analysis, and leave-one-out plot. Subsequently, the effective gene locus was chosen for a reverse MR analysis, with positive results serving as the exposure variable. We found a causal relationship between telomere length and the expression of osteocalcin (OC), matrix metalloproteinase-3 (MMP-3), and matrix metalloproteinase-12 (MMP-12), key markers of bone metabolism. Our findings suggest that telomere wear and shortening may contribute to increased activity of OC, MMP-3, and MMP-12, thus affecting bone metabolism. However, reverse Mendelian randomization analysis did not indicate a significant impact of OC, MMP-3, and MMP-12 on telomere length, implying a unidirectional relationship. Overall, this meta-analysis underscores the association between telomere length and bone loss, highlighting the importance of timing and duration of telomere wear and shortening in influencing bone metabolism.

Electroacupuncture ameliorates senile osteoporosis by promoting bone remodeling and regulating autophagy

OBJECTIVES

Osteoporosis is widely regarded as a typical aged-related disease caused by impaired bone remodeling. This research was designed to explore the protective effects of electroacupuncture (EA) on senile osteoporosis in a rat model and investigate the underlying mechanisms.

METHODS

Three-month-old rats were randomly selected as the youth group, and 24-month-old rats were randomly assigned to the elderly and EA groups. Rats in the EA group received 30 min of EA at bilateral SP10, ST36, K13 and GB34 daily, 5 days a week for 8 weeks. Bone mineral density (BMD), microstructure of the bone tissue, bone turnover biomarkers and expression level of autophagy-related proteins were detected.

RESULTS

Compared with the elderly group, EA treatment significantly increased BMD of the femur and ameliorated the microstructure. EA treatment increased trabecular bone volume ratio (= bone volume / total volume [BV/TV]) and trabecular number (Tb.N) and decreased trabecular separation (Tb.Sp) in senile osteoporosis rats. Compared with the elderly group, the serum N-terminal telopeptide of type I collagen (NTX1) level in the EA group was lower, and the serum procollagen type I N-terminal propeptide (PINP) concentration was higher. In addition, the expression of Beclin 1, microtubule-associated protein I light chain 3 (LC3B) and P62 was inhibited in the senile osteoporosis rats after EA treatment.

CONCLUSIONS

EA can effectively alleviate aging-related bone loss and improve the microstructure of bone tissue in senile osteoporosis rats, and the regulation of autophagy might be one of the important mechanisms.

AOP Report: Development of an adverse outcome pathway for deposition of energy leading to bone loss

Bone loss, commonly seen in osteoporosis, is a condition that entails a progressive decline of bone mineral density and microarchitecture, often seen in post-menopausal women. Bone loss has also been widely reported in astronauts exposed to a plethora of stressors and in patients with osteoporosis following radiotherapy for cancer. Studies on mechanisms are well documented but the causal connectivity of events to bone loss development remains incompletely understood. Herein, the adverse outcome pathway (AOP) framework was used to organize data and develop a qualitative AOP beginning from deposition of energy (the molecular initiating event) to bone loss (the adverse outcome). This qualitative AOP was developed in collaboration with bone loss research experts to aggregate relevant findings, supporting ongoing efforts to understand and mitigate human system risks associated with radiation exposures. A literature review was conducted to compile and evaluate the state of knowledge based on the modified Bradford Hill criteria. Following review of 2029 studies, an empirically supported AOP was developed, showing the progression to bone loss through many factors affecting the activities of bone-forming osteoblasts and bone-resorbing osteoclasts. The structural, functional, and quantitative basis of each proposed relationship was defined, for inference of causal changes between key events. Current knowledge and its gaps relating to dose-, time- and incidence-concordance across the key events were identified, as well as modulating factors that influence linkages. The new priorities for research informed by the AOP highlight areas for improvement to enable development of a quantitative AOP used to support risk assessment strategies for space travel or cancer radiotherapy.

Oral and Gingival Crevicular Fluid Biomarkers for Jawbone Turnover Diseases: A Scoping Review

Gingival crevicular fluid (GCF) and oral fluid have emerged as promising diagnostic tools for detecting biomarkers. This review aimed to evaluate the existing literature on using oral fluids as a source of biomarkers for bone turnover diseases affecting the jawbone. A comprehensive search strategy was executed between August 2014 and August 2024 across five major databases (Web of Science, EBSCOhost Dentistry & Oral Sciences Source, Cochrane Library, Scopus, and PubMed) and grey literature sources. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) was applied. The screening was facilitated using Rayyan at rayyan.ai and Endnote X20 software tools, culminating in the evaluation of 14,965 citations from databases and 34 from grey literature. Following rigorous scrutiny, 37 articles were selected for inclusion in this review, encompassing diseases such as periodontitis, medication-related osteonecrosis of the jaw (MRONJ), and osteoporosis. The quality of the included observational studies was assessed using the Revised Risk of Bias Assessment Tool for Non-Randomized Studies (RoBANS 2). Interleukin-1 beta (IL-1β), sclerostin, osteoprotegerin (OPG), and interleukin-34 (IL-34) emerged as significant biomarkers in GCF, and they were mainly from periodontitis and osteoporosis. Osteocalcin (OC), IL-1β, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), OPG, and matrix metalloproteinase-9 (MMP-9) were significant in oral fluid or saliva, and they were from periodontitis, MRONJ, and osteoporosis. These findings underscore the potential use of oral fluids, which are regarded as non-invasive tools for biomarker identification in bone turnover. Many biomarkers overlap, and it is important to identify other specific biomarkers to enable accurate diagnosis of these conditions.

Additional effects of herbal medicine combined with bisphosphonates for primary osteoporosis: a systematic review and meta-analysis

Background

Osteoporosis (OP) is a significant medical issue associated with population aging. Recent research on herbal medicines (HMs) for OP has been increasing, with these therapies sometimes used in conjunction with bisphosphonates (BPs), the standard treatment for OP. We conducted a systematic review and meta-analysis to evaluate the effects of combining HMs with BPs on improving bone mineral density (BMD) in patients with primary OP.

Methods

We searched nine databases-PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure Wanfang, KISS, Kmbase, Science On, and Oasis-up to 31 August 2023. We selected randomized controlled trials (RCTs) comparing BMD between HMs plus BPs and BPs alone in primary OP. A meta-analysis with BMD as the primary outcome was performed using RevMan version 5.4. Study quality and evidence certainty were assessed through Cochrane's risk of bias2 and GRADE.

Results

Out of 43 RCTs involving 4,470 participants (mean age 65.8 ± 6.6 years), 35 RCTs with 3,693 participants were included in the meta-analysis. The combination of HMs and BPs was found to be more effective in improving BMD compared to BPs alone, with improvements of 0.10 g/cm2 at the lumbar spine (33 RCTs, 95% CI: 0.07-0.12, p < 0.001, I2 = 93%) and 0.08 g/cm2 at the femoral neck (20 RCTs, 95% CI: 0.05-0.12, p < 0.001, I2 = 94%), though this result was associated with high heterogeneity, high risk of bias, and very low certainty of evidence.

Conclusion

Our data suggest the possibility that combining HMs with BPs may improve BMD in primary OP more effectively than using BPs alone. However, the results should be interpreted with caution due to the high heterogeneity and low quality of the studies included in the review. Therefore, further well-designed RCTs are needed to confirm these findings.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023392139.

B vitamins and bone health: a meta-analysis with trial sequential analysis of randomized controlled trials

Our study showed that B vitamins did not have significant effect on fracture incidence, bone mineral density, and bone turnover markers. However, the research data of B vitamins on bone mineral density and bone turnover markers are limited, and more clinical trials are needed to draw sufficient conclusions.

PURPOSE

The objective of this study was to identify the efficacy of B vitamin (VB) (folate, B6, and B12) supplements on fracture incidence, bone mineral density (BMD), and bone turnover markers (BTMs).

METHODS

A comprehensive search was performed in PubMed, MEDLINE, EMBASE, Cochrane databases, and ClinicalTrials.gov up to September 4, 2023. The risk of bias was assessed according to Cochrane Handbook and the quality of evidence was assessed according to the GRADE system. We used trial sequential analysis (TSA) to assess risk of random errors and Stata 14 to conduct sensitivity and publication bias analyses.

RESULTS

Data from 14 RCTs with 34,700 patients were extracted and analyzed. The results showed that VBs did not significantly reduce the fracture incidence (RR, 1.06; 95% CI, 0.95 - 1.18; p = 0.33; I2 = 40%) and did not affect BMD in lumbar spine and femur neck. VBs had no significant effect on bone specific alkaline phase (a biomarker for bone formation), but could increase the serum carboxy-terminal peptide (a biomarker for bone resorption) (p = 0.009; I2 = 0%). The TSA showed the results of VBs on BMD and BTMs may not be enough to draw sufficient conclusions due to the small number of sample data included and needed to be demonstrated in more clinical trials. The inability of VBs to reduce fracture incidence has been verified by TSA as sufficient. Sensitivity analysis and publication bias assessment proved that our meta-analysis results were stable and reliable, with no significant publication bias.

CONCLUSIONS

Available evidence from RCTs does not support VBs can effectively influence osteoporotic fracture risk, BMD, and BTMs.

TRIAL REGISTRATION

PROSPERO registration number: CRD42023427508.

Mir-381-3p aggravates ovariectomy-induced osteoporosis by inhibiting osteogenic differentiation through targeting KLF5/Wnt/β-catenin signaling pathway

BACKGROUND

Increasing evidence shows the pivotal significance of miRNAs in the pathogenesis of osteoporosis. miR-381-3p has been identified as an inhibitor of osteogenesis. This study explored the role and mechanism of miR-381-3p in postmenopausal osteoporosis (PMOP), the most common type of osteoporosis.

METHODS

Bilateral ovariectomy (OVX) rat model was established and miR-381-3p antagomir was administrated through the tail vein in vivo. The pathological changes in rats were assessed through the evaluation of serum bone turnover markers (BALP, PINP, and CTX-1), hematoxylin and eosin (H&E) staining, as well as the expression of osteoblast differentiation biomarkers. Moreover, isolated bone marrow mesenchymal stem cells from OVX-induced rats (OVX-BMMSCs) were utilized to explore the impact of miR-381-3p on osteoblast differentiation. In addition, the target gene and downstream pathway of miR-381-3p were further investigated both in vivo and in vitro.

RESULTS

miR-381-3p expression was elevated, whereas KLF5 was suppressed in OVX rats. miR-381-3p antagomir decreased serum levels of bone turnover markers, improved trabecular separation, promoted osteoblast differentiation biomarker expression in OVX rats. ALP activity and mineralization were suppressed, and levels of osteoblast differentiation biomarkers were impeded after miR-381-3p overexpression during osteoblast differentiation of OVX-BMMSCs. While contrasting results were found after inhibition of miR-381-3p. miR-381-3p targets KLF5, negatively affecting its expression as well as its downstream Wnt/β-catenin pathway, both in vivo and in vitro. Silencing of KLF5 restored Wnt/β-catenin activation induced by miR-381-3p antagomir.

CONCLUSION

miR-381-3p aggravates PMOP by inhibiting osteogenic differentiation through targeting KLF5/Wnt/β-catenin pathway. miR-381-3p appears to be a promising candidate for therapeutic intervention in PMOP.

Pro-Osteogenic Effect of the Nutraceutical BlastiMin Complex® in Women with Osteoporosis or Osteopenia: An Open Intervention Clinical Trial

Osteoporosis is a chronic disease that affects millions of patients worldwide and is characterized by low bone mineral density (BMD) and increased risk of fractures. Notably, natural molecules can increase BMD and exert pro-osteogenic effects. Noteworthily, the nutraceutical BlastiMin Complex® (Mivell, Italy, European Patent Application EP4205733A1) can induce differentiation of human bone marrow mesenchymal stem cells (BM-MSCs) in osteoblasts and can exert in vitro pro-osteogenic and anti-inflammatory effects. Thus, the purpose of this study was to verify the effects of BlastiMin Complex® on bone turnover markers (BTMs) and BMD in patients with senile and postmenopausal osteopenia or osteoporosis. The efficacy of BlastiMin Complex® on BTMs in serum was evaluated through biochemical assays. BMD values were analyzed by dual-energy X-ray absorptiometry (DXA) and Radiofrequency Echographic Multi Spectrometry (R.E.M.S.) techniques, and the SNPs with a role in osteoporosis development were evaluated by PCR. Clinical data obtained after 12 months of treatment showed an increase in bone turnover index, a decrease in C-reactive protein levels, and a remarkable increase in P1NP levels, indicating the induction of osteoblast proliferation and activity in the cohort of 100% female patients recruited for the study. These findings show that the nutraceutical BlastiMin Complex® could be used as an adjuvant in combination with synthetic drugs for the treatment of osteoporosis pathology.

The Emerging Role of the Mitochondrial Respiratory Chain in Skeletal Aging

Maintenance of mitochondrial homeostasis is crucial for ensuring healthy mitochondria and normal cellular function. This process is primarily responsible for regulating processes that include mitochondrial OXPHOS, which generates ATP, as well as mitochondrial oxidative stress, apoptosis, calcium homeostasis, and mitophagy. Bone mesenchymal stem cells express factors that aid in bone formation and vascular growth. Positive regulation of hematopoietic stem cells in the bone marrow affects the differentiation of osteoclasts. Furthermore, the metabolic regulation of cells that play fundamental roles in various regions of the bone, as well as interactions within the bone microenvironment, actively participates in regulating bone integrity and aging. The maintenance of cellular homeostasis is dependent on the regulation of intracellular organelles, thus understanding the impact of mitochondrial functional changes on overall bone metabolism is crucially important. Recent studies have revealed that mitochondrial homeostasis can lead to morphological and functional abnormalities in senescent cells, particularly in the context of bone diseases. Mitochondrial dysfunction in skeletal diseases results in abnormal metabolism of bone-associated cells and a secondary dysregulated microenvironment within bone tissue. This imbalance in the oxidative system and immune disruption in the bone microenvironment ultimately leads to bone dysplasia. In this review, we examine the latest developments in mitochondrial respiratory chain regulation and its impacts on maintenance of bone health. Specifically, we explored whether enhancing mitochondrial function can reduce the occurrence of bone cell deterioration and improve bone metabolism. These findings offer prospects for developing bone remodeling biology strategies to treat age-related degenerative diseases.

Effect of type 2 diabetes on biochemical markers of bone metabolism: a meta-analysis

Objective

This meta-analysis aims to examine differences in biochemical markers of bone metabolism between individuals with type 2 diabetes (T2DM) and non-T2DM control groups.

Materials and methods

Two independent evaluators searched five databases: PubMed, EMBASE, EBSCOhost, Web of Science, and the Cochrane Library. We aimed to identify observational studies investigating the impact of T2DM on biochemical markers of bone metabolism. Literature retrieval covered the period from the establishment of the databases up to November 2022. Studies were included if they assessed differences in biochemical markers of bone metabolism between T2DM patients and non-T2DM control groups using cross-sectional, cohort, or case-control study designs.

Results

Fourteen studies were included in the analysis, comprising 12 cross-sectional studies and 2 cohort studies. Compared to the non-T2DM control group, T2DM patients showed reduced levels of Osteocalcin and P1NP, which are markers of bone formation. Conversely, levels of Alkaline phosphatase and Bone-specific alkaline phosphatase, other bone formation markers, increased. The bone resorption marker CTX showed decreased levels, while TRACP showed no significant difference.

Conclusion

In individuals with T2DM, most bone turnover markers indicated a reduced rate of bone turnover. This reduction can lead to increased bone fragility despite higher bone mineral density, potentially increasing the risk of osteoporosis.

Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php? identifier CRD42022366430.

Materials Suitable for Osteochondral Regeneration

Osteochondral defects affect articular cartilage, calcified cartilage, and subchondral bone. The main problem that they cause is a different behavior of cell tissue in the osteochondral and bone part. Articular cartilage is composed mainly of collagen II, glycosaminoglycan (GAG), and water, and has a low healing ability due to a lack of vascularization. However, bone tissue is composed of collagen I, proteoglycans, and inorganic composites such as hydroxyapatite. Due to the discrepancy between the characters of these two parts, it is difficult to find materials that will meet all the structural and other requirements for effective regeneration. When designing a scaffold for an osteochondral defect, a variety of materials are available, e.g., polymers (synthetic and natural), inorganic particles, and extracellular matrix (ECM) components. All of them require the accurate characterization of the prepared materials and a number of in vitro and in vivo tests before they are applied to patients. Taken in concert, the final material needs to mimic the structural, morphological, chemical, and cellular demands of the native tissue. In this review, we present an overview of the structure and composition of the osteochondral part, especially synthetic materials with additives appropriate for healing osteochondral defects. Finally, we summarize in vitro and in vivo methods suitable for evaluating materials for restoring osteochondral defects.

Evaluation of Biomarkers of Bone Metabolism on Salivary Matrix in the Remodeling of Periodontal Tissue during Orthodontic Treatment

The aim of this study was to evaluate changes in the concentration of N-terminal type I collagen extension pro-peptide (PINP), tartrate-resistant acid phosphatase (TRAcP), and parathyroid hormone-related protein (PTHrP) in saliva during orthodontic treatment in order to evaluate whether changes in bone turnover marker (BTM) concentration can help highlight the effects of orthodontic mechanical loading in the absence of clinical evidence of tooth movement in terms of tooth movement. Saliva samples from 25 apparently healthy young subjects (10 females and 15 males) were collected using Salivette® (Sarstedt) with cotton swabs and the concentrations of PTHrP, TRAcP 5b, and PINP were analyzed at time 0 (T1), 25 days (T2), and at 45 days (T3). Differences in the median value of biomarker levels between baseline T1 and follow-up of the different groups (T2 and T3) were assessed using the non-parametric Mann-Whitney U test. Trough concentrations of P1NP, PTHrP, and TRAcP were 0.80 µg/L, 0.21 ng/mL, and 0.90 U/L above the method LOD. The non-parametric Mann-Whitney U test confirmed a statistically significant difference in T1 versus concentrations of T2 and T3. All subjects evaluated had a statistically significant difference between T1 vs. T3. when compared with the specific critical difference (RCV) for the analyte The results obtained demonstrate that the evaluation of BTM changes in saliva can help the evaluation of orthodontic procedures and the monitoring of biomechanical therapy.

Correlations between bone metabolism biomarkers and fluoride exposure in adults and children

Increased exposure to fluoride, which notably affects bone metabolism, is a global concern. However, the correlations and sensitivity of bone metabolism to fluoride remain controversial. In this cross-sectional study, 549 children (aged 7-12 years) and 504 adults (≥ 18 years old) were recruited in the high-fluoride areas of the Henan Province. Urinary fluoride (UF) level was determined using a fluoride electrode. Fasting venous blood serum was collected to measure bone metabolism biomarkers. The selected bone metabolism biomarkers for children included bone alkaline phosphatase (BALP), serum alkaline phosphatase (ALP), osteocalcin (OCN), calcitonin (CT), parathyroid hormone (PTH), phosphorus (P5+), and calcium (Ca2+). For adults, the biomarkers included ALP, CT, PTH, β-CrossLaps (β-CTX), P5+, and Ca2+. The correlations between UF and bone metabolism biomarkers were analyzed using binary logistic regression, a trend test, a generalized additive model, and threshold effect analysis. Regression analysis indicated a significant correlation between serum OCN, PTH, and UF levels in children aged 7-9 years. Serum OCN, PTH, and BALP contents were significantly correlated with UF in boys (P < 0.05). Furthermore, the interaction between age and UF affected serum P5+ and PTH (P < 0.05). The generalized additive model revealed nonlinear dose-response relationships between P5+, BALP, and UF contents in children (P < 0.05). Serum OCN level was linearly correlated with the UF concentration (P < 0.05). Similarly, a significant correlation was observed between β-CTX and UF levels in adults. In addition, significant correlations were observed between UF-age and serum Ca2+, β-CTX, and PTH contents. There was a non-linear correlation between serum Ca2+, P5+, and β- CTX and UF levels (P < 0.05). Overall, serum OCN, BALP, and P5+ levels can serve as sensitive bone metabolism biomarkers in children, while β-CTX, P5+, and Ca2+ can be considered fluoride-sensitive bone metabolism biomarkers in adults.

Identification of novel risk factors for postoperative severe hypocalcemia in patients with primary hyperparathyroidism undergoing parathyroidectomy: a case control study

BACKGROUND

Patients with primary hyperparathyroidism (PHPT) are at risk for severe hypocalcemia (SH) following parathyroidectomy (PTX), but limited data exist on the predictors of SH. We aimed to identify risk factors for early postoperative SH after PTX in patients with PHPT and to evaluate the predictive value of clinical parameters.

METHODS

A retrospective review of patients with PHPT who underwent PTX between January 2010 and December 2022 was performed. A total of 46 patients were included in the study, with 15 (32.6%) experiencing postoperative SH, 19 (41.3%) having calculi in the ureter or kidney, and 37 (80.4%) having osteoporosis. Patients were divided into SH and non-SH groups based on postoperative serum calcium levels. Preoperative biochemical indicators, bone turnover markers, and renal function parameters were analyzed and correlated with postoperative SH.

RESULTS

Statistically significant (P < 0.05) differences were found in preoperative serum calcium (serum Ca), intact parathyroid hormone, serum phosphorus (serum P), serum Ca/P, percentage decrease of serum Ca, total procollagen type 1 intact N-terminal propeptide, osteocalcin (OC), and alkaline phosphatase levels between the two groups. Multivariate analysis showed that serum P (odds ratio [OR] = 0.989; 95% confidence interval [95% CI] = 0.981-0.996; P = 0.003), serum Ca (OR = 0.007; 95% CI = 0.001-0.415; P = 0.017), serum Ca/P (OR = 0.135; 95% CI = 0.019-0.947; P = 0.044) and OC levels (OR = 1.012; 95% CI = 1.001-1.024; P = 0.036) were predictors of early postoperative SH. The receiver operating characteristic curve analysis revealed that serum P (area under the curve [AUC] = 0.859, P < 0.001), serum Ca/P (AUC = 0.735, P = 0.010) and OC (AUC = 0.729, P = 0.013) had high sensitivity and specificity.

CONCLUSION

Preoperative serum P, serum Ca/P and osteocalcin levels may identify patients with PHPT at risk for early postoperative SH after PTX.

Use of data-independent acquisition mass spectrometry to identify an objective serum indicator of the need for osteoporotic therapeutic intervention

Osteoporosis is characterized by weakened bone microstructure and loss of bone mass. Current diagnostic criteria for osteoporosis are based on the T-score, which is a measure of bone mineral density. However, osteoporotic fragility fractures can occur regardless of the T-score, underscoring the need for additional criteria for the early detection of patients at fracture risk. To identify indicators of reduced bone strength, we performed serum proteomic analysis using data-independent acquisition mass spectrometry with serum samples from two patient groups, one with osteoporosis but no fractures and the other with osteopenia and fragility fractures. Collective evaluation of the results identified six serum proteins that changed to a similar extent in both patient groups compared with controls. Of these, extracellular matrix protein 1 (ECM1), which contributes to bone formation, showed the most significant increase in serum levels in both patient groups. An ELISA-based assay suggested that ECM1 could serve as a serum indicator of the need for therapeutic intervention; however, further prospective studies with a larger sample size are necessary to confirm these results. The present findings may contribute to the provision of early and appropriate therapeutic strategies for patients at risk of osteoporotic fractures. SIGNIFICANCE: This study aimed to identify objective serum indicators of the need for therapeutic intervention in individuals at risk of osteoporotic fracture. Comprehensive proteome analyses of serum collected from patients with osteoporosis but no fractures, patients with osteopenia and fragility fractures, and controls were performed by data-independent acquisition mass spectrometry. Collective evaluation of the proteome analysis data and ELISA-based assays identified serum ECM1 as a potential objective marker of the risk of fragility fractures in patients with osteoporosis or osteopenia. The findings are an important step toward the development of appropriate bone health management methods to improve well-being and maintain quality of life.

Sex-specific associations of urinary mixed-metal concentrations with femoral bone mineral density among older people: an NHANES (2017-2020) analysis

Background

Heavy metal exposure is an important cause of reduced bone mineral density (BMD). Epidemiological studies focusing on the effects of mixed heavy metal exposure on BMD in middle-aged and older people are scarce. In single-metal studies, men and women have shown distinct responses of BMD to environmental metal exposure. This study therefore aimed to elucidate the association between mixed heavy metal exposure and BMD and to investigate whether it is sex-specific.

Methods

Data from the 2017-2020 National Health and Nutrition Examination Survey were selected for this cross-sectional study. The study used three statistical methods, i.e., linear regression, Bayesian kernel machine regression (BKMR) modeling, and weighted quartiles (WQS) regression, to explore the association between the urinary concentrations of 11 metals (barium, cadmium, cobalt, cesium, manganese, molybdenum, lead, antimony, tin, thallium, and Tungsten), either individually or as a mixture, and total femoral BMD.

Results

A total of 1,031 participants were included in this study. Femoral BMD was found to be higher in men than women. A significant negative correlation between the urinary concentrations of the 10 metals and femoral BMD was found in the overall cohort. Further gender sub-stratified analyses showed that in men, urinary metal concentrations were negatively correlated with femoral BMD, with cobalt and barium playing a significant and non-linear role in this effect. In women, although urinary metal concentrations negatively modulated femoral BMD, none of the correlations was statistically significant. Antimony showed sex-specific differences in its effect.

Conclusion

The urinary concentrations of 10 mixed heavy metals were negatively correlated with femoral BMD in middle-aged and older participants, and this effect showed gender differences. These findings emphasize the differing role of mixed metal exposure in the process of BMD reduction between the sexes but require further validation by prospective studies.

Effects of sodium-glucose cotransporter 2 inhibitors on bone metabolism in patients with type 2 diabetes mellitus: a systematic review and meta-analysis

BACKGROUND

Sodium glucose cotransporter 2 (SGLT2) inhibitors are widely used in type 2 diabetes mellitus (T2DM) therapy. The impact of SGLT2 inhibitors on bone metabolism has been widely taken into consideration. But there are controversial results in the study on the effect of SGLT2 inhibitors on bone metabolism in patients with T2DM. Therefore, we aimed to examine whether and to what extent SGLT2 inhibitors affect bone metabolism in patients with T2DM.

METHODS

A literature search of randomized controlled trials (RCTs) was conducted through PubMed, Web of Science, Embase, Cochrane databases, and Scopus from inception until 15 April 2023. Eligible RCTs compared the effects of SGLT2 inhibitors versus placebo on bone mineral density and bone metabolism in patients with T2DM. To evaluate the differences between groups, a meta-analysis was conducted using the random effects inverse-variance model by utilizing standardized mean differences (SMD).

RESULTS

Through screening, 25 articles were finally included, covering 22,828 patients. The results showed that, compared with placebo, SGLT2 inhibitors significantly increased parathyroid hormone (PTH, SMD = 0.13; 95%CI: 0.06, 0.20), and cross-linked C-terminal telopeptides of type I collagen (CTX, SMD = 0.11; 95%CI: 0.01, 0.21) in patients with T2DM, decreased serum alkaline phosphatase levels (ALP, SMD = -0.06; 95%CI: -0.10, -0.03), and had no significant effect on bone mineral density (BMD), procollagen type 1 N-terminal propeptide (P1NP), 25-hydroxy vitamin D, tartrate resistant acid phosphatase-5b (TRACP-5b) and osteocalcin.

CONCLUSIONS

SGLT2 inhibitors may negatively affect bone metabolism by increasing serum PTH, CTX, and decreasing serum ALP. This conclusion needs to be verified by more studies due to the limited number and quality of included studies.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, identifier CRD42023410701.

Effects of Erythropoietin-Promoted Fracture Healing on Bone Turnover Markers in Cats

In orthopaedics, erythropoietin (EPO) is applied in the preoperative management of anaemic patients, but also as a stimulating factor to assist bone regeneration due to its angiogenic and osteoinductive potential. Since orthopaedists mainly rely on their clinical experience to assess bone healing, additional and more objective methods such as studying the dynamics of bone markers are needed. Therefore, the aim of this study was to investigate the plasma activity of bone-specific alkaline phosphatase (BALP), the N-terminal propeptide of type I collagen (PINP), the C-terminal telopeptide of type I collagen (CTX), and deoxypyridinoline (DPD) during the first 2 months of healing of comminuted fractures in cats, either non-stimulated or locally stimulated with recombinant human erythropoietin (rhEPO). The study included twelve cats of mixed breeds, aged 7.2 ± 4 months, weighing 2.11 ± 1.1 kg, with comminuted diaphyseal fractures of the femur. Surgical treatment with plate osteosynthesis was performed in all animals. The cats were randomly divided into two groups-a control (n = 6) and an EPO group (n = 6). The locally applied EPO leads to the increased activity of bone formation markers (BALP and PINP) during the second week after the osteosynthesis, preceding the peaks in the control group by two weeks. The studied bone resorption markers (DPD, CTX) varied insignificantly during the studied period. In conclusion, erythropoietin could serve as a promoter of bone healing in comminuted fractures in cats.

Cistanche deserticola improves ovariectomized-induced osteoporosis mainly by regulating lipid metabolism: Insights from serum metabolomics using UPLC/Q-TOF-MS

ETHNOPHARMACOLOGICAL RELEVANCE

Cistanche deserticola (C. deserticola) is an edible and traditional medicine widely used in China, which has been confirmed to be effective in the treatment of postmenopausal osteoporosis (PMOP). Despite its proven efficacy, the exact role of C. deserticola in bone metabolism and its underlying mechanism has remained unclear.

AIM OF THE STUDY

In this research, we employed an in vivo model utilizing ovariectomized (OVX) rats to characterize the anti-osteoporotic activity and metabolic mechanism of the ethanol extract of C. deserticola (CHE).

MATERIALS AND METHODS

Fifty female Sprague-Dawley (SD) rats were randomly divided into five groups including sham operation group, model group, 0.1 g/kg estradiol valerate (EV) group as the positive control, low (0.6 g/kg) and high (1.2 g/kg) dosage CHE groups. Biochemical parameter analyses and histopathological experiments were conducted to assess the pharmacodynamic effects. Metabolomic analysis was conducted on serum samples to examine the metabolic profiles, identify potential biomarkers, and elucidate the metabolic pathways associated with CHE in OVX rats.

RESULTS

CHE treatment demonstrated significant anti-osteoporosis activity by regulating serum biochemical markers of bone turnover, improving cancellous bone structure, and reversing the decrease in bone mineral density. Furthermore, the clinical equivalent dose group (CHL) achieved superior overall outcomes. The main interventions of CHE on OVX rats involved the modulation of several key pathways, including steroid hormone biosynthesis, arachidonic acid metabolism, tyrosine and tryptophan metabolism, biotin metabolism, regulation of TRP channels by inflammatory mediators, primary bile acid biosynthesis, regulation of lipolysis in adipocytes, and bile secretion. 23 potential efficacy-related biomarkers within the metabolic network were identified. Among them, long-chain unsaturated fatty acids (eg. DHA and docosapentaenoic acid), steroid hormones, amino acids and carbohydrates were strongly correlated with bone resorption and formation markers. Additionally, it was observed four pathways (nucleotide, carbon, amino acid, and lipid metabolism) were implicated in the effects of CHE.

CONCLUSION

This study demonstrates that CHE improves bone loss in PMOP mainly through regulating lipid metabolism pathways, which provides an evidence base for CHE treatment of PMOP.

Amorphous Calcium Carbonate from Plants Can Promote Bone Growth in Growing Rats

OBJECTIVES

This study aimed to investigate the effect of amorphous calcium carbonate (ACC) supplementation on bone growth in growing rats.

METHODS

We used 3-week-old male Wistar rats to simulate childhood and adolescent growth stages. Rats were divided into four groups as follows: a control group (C), a low-dose group (L, 20.65 mg/kg body weight (BW) ACC), a medium-dose group (M, 206.5 mg/kg BW ACC), and a high-dose group (H, 413 mg/kg BW ACC) administered by gavage. Body length (BL) and BW were measured weekly. The bone mineral density (BMD) of two lumbar vertebrae (L3 and L4) and the left femur were analyzed by micro-computed tomography (μCT) at 0, 4, 8, and 12 weeks. At the end of 12 weeks, the rats were sacrificed. After that, blood samples were collected from the abdominal aorta. Femurs and tibias were collected and weighed, and their lengths were measured. Then, bone samples were used to perform histopathological and histomorphometric analyses.

RESULTS

It showed that ACC supplementation in growing rats increased the trabecular bone thickness and serum bone formation biomarkers. Furthermore, high-dose ACC decreased serum bone resorption biomarkers and increased BMD.

CONCLUSIONS

ACC supplementation can enhance osteoblast metabolism and inhibit osteoclast metabolism, resulting in a higher bone formation rate compared to bone resorption. This led to increased trabecular bone thickness, a higher BMD, and supported bone growth.

Cyclin A1 (CCNA1) inhibits osteoporosis by suppressing transforming growth factor-beta (TGF-beta) pathway in osteoblasts

BACKGROUND

Osteoporosis is a genetic disease caused by the imbalance between osteoblast-led bone formation and osteoclast-induced bone resorption. However, further gene-related pathogenesis remains to be elucidated.

METHODS

The aberrant expressed genes in osteoporosis was identified by analyzing the microarray profile GSE100609. Serum samples of patients with osteoporosis and normal group were collected, and the mRNA expression of candidate genes was detected by quantitative real-time polymerase chain reaction (qRT-PCR). The mouse cranial osteoblast MC3T3-E1 cells were treated with dexamethasone (DEX) to mimic osteoporosis in vitro. Alizarin Red staining and alkaline phosphatase (ALP) staining methods were combined to measure matrix mineralization deposition of MC3T3-E1 cells. Meanwhile, the expression of osteogenesis related genes including alkaline phosphatase (ALP), osteocalcin (OCN), osteopontin (OPN), Osterix, and bone morphogenetic protein 2 (BMP2) were evaluated by qRT-PCR and western blotting methods. Then the effects of candidate genes on regulating impede bone loss caused by ovariectomy (OVX) in mice were studied.

RESULTS

Cyclin A1 (CCNA1) was found to be significantly upregulated in serum of osteoporosis patients and the osteoporosis model cells, which was in line with the bioinformatic analysis. The osteogenic differentiation ability of MC3T3-E1 cells was inhibited by DEX treatment, which was manifested by decreased Alizarin Red staining intensity, ALP staining intensity, and expression levels of ALP, OCN, OPN, Osterix, and BMP2. The effects of CCNA1 inhibition on regulating osteogenesis were opposite to that of DEX. Then, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis demonstrated that genes negatively associated with CCNA1 were enriched in the TGF-beta signaling pathway. Inhibitor of TGF-beta signaling pathway partly reversed osteogenesis induced by suppressed CCNA1. Furthermore, suppressed CCNA1 relieved bone mass of OVX mice in vivo.

CONCLUSION

Downregulation of CCNA1 could activate TGF-beta signaling pathway and promote bone formation, thus playing a role in treatment of osteoporosis.

The detection of Gper1 as an important gene promoting jawbone regeneration in the context of estrogen deficiency

Numerous studies have demonstrated that estrogen deficiency inhibit the proliferation and differentiation of pre-osteoblasts in skeleton by affecting osteogenic signaling, lead to decreased bone mass and impaired regeneration. To explore the mechanisms maintaining bone regeneration under estrogen deficiency, we randomly selected 1102 clinical cases, in which female patients aged between 18 and 75 have underwent tooth extraction in Stomatological Hospital of Tongji University, there is little difference in the healing effect of extraction defects, suggesting that to some extent, the regeneration of jawbone is insensitive to the decreased estrogen level. To illuminate the mechanisms promoting jawbone regeneration under estrogen deficiency, a tooth extraction defect model was established in the maxilla of female rats who underwent ovariectomy (OVX) or sham surgery, and jawbone marrow stromal cells (BMSCs) were isolated for single-cell sequencing. Further quantitative PCR, RNA interference, alizarin red staining, immunohistochemistry and western blotting experiments demonstrated that in the context of ovariectomy, maxillary defects promoted G protein-coupled estrogen receptor 1 (Gper1) expression, stimulate downstream cAMP/PKA/pCREB signaling, and facilitate cell proliferation, and thus provided sufficient progenitors for osteogenesis and enhanced the regeneration capacity of the jawbone. Correspondingly, the heterozygous deletion of the Gper1 gene attenuated the phosphorylation of CREB, led to decreased cell proliferation, and impaired the restoration of maxillary defects. This study demonstrates the importance of Gper1 in maintaining jawbone regeneration, especially in the context of estrogen deficiency.

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.

Serum Markers of Bone Turnover Following Controlled Administration of Two Medical Cannabis Products in Healthy Adults

Introduction: Cannabidiol (CBD) has been shown to maintain bone integrity in pre-clinical models, but little is known about the effects of delta-9-tetrahydrocannabinol (THC) on bone turnover. In this study we explored the effects of two oral medical cannabis products on normal bone homeostasis through evaluation of markers of bone resorption (carboxyl-terminal collagen crosslinks, CTx) and bone formation (procollagen type 1 N-terminal propeptide, P1NP; alkaline phosphatase, ALP). Methods: This study is an analysis of secondary data from two Phase 1 double-blind, placebo-controlled trials of Spectrum Yellow (0.9 mg THC, 20 mg CBD/mL of oil) and Spectrum Red (2.5 mg THC, 0.3 mg CBD/softgel). Healthy participants (n=38 men, 45 women) were randomized to receive 5-20 mg THC (CBD levels varied as a function of administered product) or placebo daily (BID) for 7 days. Bone markers were assessed at baseline, upon completion of product administration (day 8), and after a 5-day washout (day 13). Results: All bone markers were significantly higher in men at baseline (p≤0.008). For CTx, there was a significant day×group interaction (F=3.23, p=0.04); CTx levels were significantly lower in participants treated with Spectrum Red (b=-164.28; 95% confidence interval [CI], -328 to -0.29; p=0.04) and marginally lower in participants treated with Spectrum Yellow (b=-157.31; 95% CI, -323 to 8.68; p=0.06) versus placebo on day 8. For P1NP and ALP, there were no significant differences between treatments across study days. Bone marker values outside the reference range (RR) were observed; CTx > RR (n=71) was predominantly (85.9%) observed in male participants, whereas P1NP > RR (n=100) was more evenly distributed between sexes (53.0% in men). These were not considered clinically significant and did not differ between treatment groups. Conclusions: These are the first interventional human data on the effect of cannabinoids on biomarkers of bone turnover. Short-term treatment with CBD- or THC-dominant medical cannabis products resulted in attenuation of a marker of bone resorption. Although the attenuation was not clinically significant, this finding may be indicative of protective properties of cannabinoids in bone. Further research over longer dosing durations in individuals exhibiting bone-specific conditions (e.g., osteoporosis) is warranted. ClinicalTrials.gov IDs: ACTRN12619001723178 and ACTRN12619001450101.

The impact of Resolvin E1 on bone regeneration in critical-sized calvarial defects of rat model-A gene expression and micro-CT analysis

OBJECTIVE

To investigate, in vivo, the effect of local application of Resolvin E1 (RvE1) on the bone regeneration of critical-size defects (CSDs) in Wistar rats utilizing gene expression and micro-computed tomographic (micro-CT) analysis.

BACKGROUND

The inflammation-resolving actions of RvE1 are well established. The molecular mechanism of its bone-regenerative actions has been of significant interest in recent years; however, there is limited information regarding the same.

MATERIALS AND METHODS

Thirty Wistar rats with a 5 mm induced critical-size calvarial defect were randomly allocated into four groups: no treatment/negative control (n = 5), treatment using bovine bone grafts/positive control (n = 5), treatment using local delivery of RvE1 (n = 11) and treatment using RvE1 mixed with bovine bone graft (n = 9). After 4 weeks, RNA isolation, complementary DNA synthesis and real-time polymerase chain reaction were used for genetic expression of alkaline phosphatase (ALP), osteocalcin (OCN) and osteopontin (OPN). The rats were sacrificed after 12 weeks and micro-CT imaging was performed to analyse the characteristics of the newly formed bone (NFB). The data were analysed using ANOVA and the least significant difference tests (α ≤ .05).

RESULTS

The RvE1 + bovine graft group had statistically highest mean NFB (20.75 ± 2.67 mm3 ) compared to other groups (p < .001). Similarly, RvE1 + bovine graft group also demonstrated statistically highest mean genetic expression of ALP (31.71 ± 2.97; p = .008) and OPN (34.78 ± 3.62; p < .001) compared to negative control and RvE1 groups.

CONCLUSION

Resolvin E1 with adjunct bovine bone graft demonstrated an enhanced bone regeneration compared to RvE1 or bovine graft alone in the calvarial defect of Wistar rats.

HSP90 Exacerbates Bone Destruction in Rheumatoid Arthritis by Activating TRAF6/NFATc1 Signaling

Rheumatoid arthritis (RA) is an autoimmune disease characterized by a notably high disability rate, primarily attributed to cartilage and bone degradation. The involvement of heat shock protein 90 (HSP90) as a molecular chaperone in the inflammatory response of RA has been established, but its role in bone destruction remains uncertain. In the present study, the expression of HSP90 was augmented in osteoclasts induced by the receptor activator of nuclear factor-κB ligand. Additionaly, it was observed that the outcomes revealed a noteworthy inhibition of osteoclast formation and differentation when triptolide was utilized to hinder the expression of HSP90. Furthermore, the positive influence of HSP90 in osteoclast differentiation was substantiated by overexpressing HSP90 in osteoclast precursor cells. Mechanically, HSP90 significantly activated the TNF receptor-associated factor 6 (TRAF6)/Nuclear factor of activated T cells 1 (NFATc1) signaling axis, accompanied by markedly promoting osteoclast differentiation. This effect was consistently observed in the destructive joint of rats with collagen-induced arthritis, where HSP90 effectively activated osteoclasts and contributed to arthritic bone destruction by activating the TRAF6/NFATc1 signaling. Overall, the findings of this study provide compelling evidence that HSP90 exacerbates bone destruction in RA by promoting osteoclast differentiation through the activation of TRAF6/NFATc1 signaling, and interference with HSP90 may be a promising strategy for the discovery of anti-arthritic bone destruction agents.

Changes in mandibular radiomorphometric indices in osteoporosis patients treated with denosumab: a retrospective case-control study

BACKGROUND

Radiomorphometric indices measured on Dental Panoramic Radiography (DPR) can reflect Bone Mineral Density (BMD). The aim of our study is to evaluate changes in DPR radiographic markers in patients undergoing antiresorptive therapy with denosumab and correlate them to BMD and serum bone turnover markers (BTM).

METHODS

We evaluated two radiomorphometric indices: Mandibular Cortical Width (MCW) and Panoramic Mandibular Index (PMI), in patients undergoing antiresorptive therapy with denosumab at T0 (before starting the therapy) and at T1 (after 12 months), comparing results with a control group of healthy patients who performed two DPRs at a one-year time distance. Correlation analysis was performed in the denosumab group, as well as ROC curves were obtained for both indices.

RESULTS

The study included 18 patients and 21 controls according to specific inclusion and exclusion criteria, matched by gender and age. Both MCW and PMI were significantly lower at T0 in the denosumab group, consistently with lower BMD. MCW showed significant correlation with femoral and lumbar DEXA and was significantly lower in patients with osteoporosis compared to osteopenia. Only PMI index increased significantly in the denosumab group from T0 to T1. After one year (T1), there weren't any differences between patients and controls for both indices. No significant correlations were found with BTMs. Sensitivity and specificity for MCW and PMI were also calculated.

CONCLUSIONS

Our results show how CMW shows sufficient sensitivity and specificity to be used as a radiographic marker to screen and intercept patients with osteoporosis. PMI seems to be able to reflect changes in response to antiresorptive therapy with denosumab. Further studies are needed to confirm our hypothesis.

Association of lymphocyte subsets and cytokines with bone metabolism: a retrospective, cross-sectional study

BACKGROUND

Previous research has shown that lymphocytes and cytokines can mediate bone metabolism. This study explored the clinical association and predictive ability of lymphocytes and cytokines levels for bone metabolism.

METHODS

A total of 162 patients were enrolled in this study. The levels of N-terminal propeptide of type I procollagen (P1NP), β-collagen degradation product (β-CTX), total T lymphocytes, immature T lymphocytes, suppressor/cytotoxic T lymphocytes, helper/inducer T lymphocytes, B lymphocytes, natural killer (NK) cells, Interferon-gamma (IFN-γ), tumour necrosis factor-alpha (TNF-α), IFN-α, interleukin-1 beta (IL-1β), IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, and IL12p70 were evaluated. The relationship between these lymphocyte subsets and cytokines with bone metabolic status was examined and their predictive ability for bone metabolic status was assessed.

RESULTS

The principal component analysis (PCA) and correlation analysis results varied on differences in lymphocyte subsets and cytokines in various bone metabolism states. Differential analysis revealed significant differences in the absolute counts of B lymphocytes (P < 0.05), level of IL-12p70 (P < 0.05), and IL-8 (P < 0.001) at different P1NP levels. Significant differences were observed in the absolute counts of total T lymphocytes (P < 0.05), B lymphocytes (P < 0.05), the level of IL-6 (P < 0.05), the percentage of B lymphocytes (P < 0.01), and NK cells (P < 0.05) at different β-CTX levels. Furthermore, the receiver operating characteristic (ROC) curve showed that the absolute count of B lymphocytes and levels of IL-12p70 and IL-8 could be used to evaluate bone formation states, while the absolute counts of T and B lymphocytes, level of IL-6, and percentages of NK cells and B lymphocytes could be used to evaluate bone resorption states.

CONCLUSION

The bone metabolism status changed based on the lymphocyte subsets and cytokine levels. Differentially expressed lymphocytes and cytokines could be used to distinguish bone metabolism status.