Menopausal hormone therapy for the management of osteoporosis

Elevated sclerostin levels contribute to reduced bone mineral density in non-ambulatory stroke patients

Osteoporosis following stroke is a significant impediment to patient recovery. Decreased mechanical loading and locomotion following the onset of paralysis in stroke patients, especially those who are non-ambulatory, contributes greatly to bone loss. Sclerostin, a protein encoded by the SOST gene, accumulates as a result of reduced mechanical loading and inhibits bone formation. This study explores the relationship between mechanical unloading, sclerostin levels, and bone mineral density (BMD) in stroke patients, utilizing three cohorts. Analysis of Cohort 1, consisting of patients with available sclerostin level measurements, found significantly elevated sclerostin levels in non-ambulatory patients compared to ambulatory patients, indicating the influence of ambulatory status on sclerostin regulation. Cohort 2, consisting of patients with BMD measurements, demonstrated that prolonged mechanical unloading in non-ambulatory patients resulted in a greater decline in BMD over time. Analysis in Cohort 3 patients, who had bilateral BMD measurements available, revealed that hemiplegic sides subjected to reduced mechanical loading exhibited lower BMD compared to non-hemiplegic sides. These findings collectively confirm the hypothesis that reduced mechanical loading elevates sclerostin levels and accelerates bone loss. By integrating data across the three cohorts, this study underscores the critical impact of mechanical unloading on bone health, particularly in chronic stroke patients with limited mobility. Our study provides clinical insights for treatments integrating ambulatory status, sclerostin levels, and BMD in chronic stroke patients and highlights an increased need for therapeutics targeting mechanical loading pathways and sclerostin accumulation which can be administered to treat chronic osteoporosis following stroke.

Saliva-based Hormone Diagnostics: advances, applications, and future perspectives

INTRODUCTION

Saliva has emerged as an important biological fluid for diagnostics, particularly hormone analysis. Its noninvasive collection and accessibility make it a compelling alternative to traditional blood-based diagnostics, enabling detection of biomarkers reflecting physiological and pathological conditions.

AREAS COVERED

This review examines hormones measurable in saliva, including cortisol, testosterone, progesterone, estradiol, dehydroepiandrosterone (DHEA), and others. It highlights methods such as Enzyme-Linked Immunosorbent Assay (ELISA), Radioimmunoassay, and Liquid Chromatography coupled with Tandem Mass Spectrometry (LC-MS/MS) for hormonal analysis, focusing on their sensitivity and challenges. The discussion addresses the advantages and limitations of saliva as a diagnostic medium, including practicality and susceptibility to external influences. Clinical applications are explored, including stress monitoring, hormonal dysfunction diagnosis, and applications in personalized medicine.

EXPERT OPINION

Salivary diagnostics holds significant potential in clinical and research contexts, particularly for hormone analysis. Despite challenges such as hormonal variability and technical limitations, advances are steadily overcoming these barriers. The noninvasive and accessible nature of saliva collection positions it as a promising medium for diagnostic innovation. Continued research, coupled with standardization of techniques, will be critical to fully harnessing saliva-based diagnostics for advancing personalized medicine, influencing the detection, diagnosis, and prognosis of certain conditions.

Achieving Menopausal Health Equity Network (AMEN): an educational intervention to improve OB/GYN knowledge of menopause-related racial and ethnic health disparities

OBJECTIVES

To study the impact of an educational intervention on obstetrician-gynecologist clinicians' knowledge of racial and ethnic disparities in the menopause experience.

METHODS

Twenty-five obstetrician-gynecologist physicians (residents, fellows, and attendings) at an academic medical center in New York, NY, completed the Achieving Menopausal Health Equity Network course, a brief web-based intervention consisting of four modules delivered through narrated didactic videos and interactive tools, a 10-item pretest and posttest, and a course evaluation survey. The primary outcome was a change in knowledge scores after the completion of the educational intervention. Item analysis was also performed to assess item discrimination, item difficulty, and response frequency. Feedback on modules was obtained, and thematic analysis was performed.

RESULTS

In this study, 25 participants completed the educational intervention. There was a statistically significant increase in mean test scores after participation (pretest mean score=7.1/10 vs. posttest mean score=8.1/10, P =0.0021). The following themes emerged in thematic analysis: knowledge building with potential for practical application for clinicians and non-clinicians, clarity and relevance, and opportunities for growth for future iterations of the modules.

CONCLUSIONS

This brief, online educational curriculum focused on racial and ethnic disparities in menopause significantly improved the knowledge of obstetrician-gynecologist clinicians at various levels of training and provides a useful model for introducing more formal training on menopause medicine for obstetrician-gynecologist clinicians.

Evaluation of Top-Ranked Search Engine Web-Based Osteoporosis Materials

OBJECTIVE

The purpose of this study was to examine the health literacy and quality of information on online Web sites about osteoporosis using the suitability assessment of materials (SAM) method.

METHODS

The search terms "osteoporosis" and "weak bones" were entered separately into three different search engines: Google, Bing, and Yahoo. Five Web sites were found on all three search engines for each search term, totaling 10 Web sites. Four different researchers graded the Web sites using the SAM scale and then averaged them.

RESULTS

For the osteoporosis search term Web sites, 60% were rated superior and 40% were rated adequate by the SAM method. The average reading grade level was 10.2, with 20% of Web sites rated superior and 40% rated adequate. Sixty percent of Web sites contained graphics, with only one Web site rated superior. In addition, 80% of Web sites were found to be unsuitable for having a summary. For the weak bones search term Web sites, 80% were rated adequate and only 20% were rated superior. The reading grade level was 9.8, with 40% of the Web sites rated adequate and 60% rated not suitable.

CONCLUSIONS

Web sites about osteoporosis contain a higher reading grade level than the national average of 7th grade. Most Web sites lack an ending summary of key points and graphics to aid comprehension. Health information Web sites about osteoporosis need to contain a lower reading grade level, more graphics, and summaries to increase the comprehension of readers.

Re-engineering bone: pathogenesis, diagnosis and emerging therapies for osteoporosis

Osteoporosis, a multifaceted metabolic bone disease, is becoming increasingly prevalent and poses a significant burden on global healthcare systems. Given the limitations of traditional treatments such as pharmacotherapy, tissue engineering has emerged as a promising alternative for osteoporosis management. This review begins by exploring the pathogenesis of osteoporosis, with a focus on the abnormal metabolic, cellular, and molecular signalling microenvironments that drive the disease. We also examine commonly used clinical diagnostic techniques, discussing their strengths and limitations. Notably, this review evaluates various advanced tissue engineering strategies for osteoporosis treatment. Delivery systems, including injectable hydrogels and nanomaterials, are detailed alongside bone tissue engineering materials such as bioactive ceramics, bone cements, and polymers. Additionally, biologically active substances, including exosomes and cytokines, and emerging therapies that leverage small-molecule drugs are explored. Through a comprehensive analysis of the advantages and limitations of current biomaterials and therapeutic approaches, this review provides insights into future directions for tissue engineering-based solutions. By synthesizing current advancements, it aims to inspire innovative perspectives for the clinical management of osteoporosis.

Molecular mechanisms and treatment strategies for estrogen deficiency-related and glucocorticoid-induced osteoporosis: a comprehensive review

Osteoporosis, a debilitating condition characterized by reduced bone mass and increased fracture risk, is notably influenced by estrogen deficiency and glucocorticoid treatment. This comprehensive review elucidates the molecular mechanisms underpinning estrogen deficiency-related osteoporosis (EDOP) and glucocorticoid-induced osteoporosis (GIOP). The role of estrogen in bone metabolism is critically examined, highlighting its regulatory effects on bone turnover and formation through various signaling pathways. Conversely, this review explores how glucocorticoids disrupt bone homeostasis, focusing on their impact on osteoclast and osteoblast function and the subsequent alteration of bone remodeling processes. The pathogenesis of both conditions is intertwined, with estrogen receptor signaling pathways and the role of inflammatory cytokines being pivotal in driving bone loss. A detailed analysis of pathogenetic and risk factors associated with EDOP and GIOP is presented, including lifestyle and genetic factors contributing to disease progression. Modern therapeutic approaches emphasize pharmacologic, non-pharmacologic, and herbal treatments for managing EDOP and GIOP. In summary, current therapeutic strategies highlight the efficacy and the safety of various interventions. This review concludes with future directions for research, suggesting a need for novel treatment modalities and a deeper understanding of the underlying mechanisms of osteoporosis. By addressing the multifaceted nature of EDOP and GIOP, this work aims to provide insights into developing targeted therapeutic strategies and improving patient outcomes in osteoporosis management.

Serum uric acid/creatinine ratio and osteoporosis in the elderly: a NHANES study

Background

Osteoporosis (OP) is a metabolic bone disorder that is of significant concern to the elderly. However, few studies have investigated the correlation between the serum uric acid to creatinine ratio (UA/Cr) and OP in elderly individuals. This research seeks to examine the connection between UA/Cr levels and OP in older adults.

Methods

Data on participant information for the study was obtained from four cycles of the NHANES database. Multivariable logistic regression was employed to examine the correlation between UA/Cr and OP, adjusting for potential confounders such as age, gender, and race. The diagnostic efficacy of UA/Cr for OP was evaluated utilizing ROC curves.

Results

Multivariable logistic regression analysis showed that serum UA/Cr levels were significantly lower in individuals with OP than in those without OP. (OR = 0.83 [0.76, 0.91], P < 0.001). Subgroup analyses indicated a stronger association in men (OR = 0.77 [0.64, 0.94], P = 0.009) and women (OR = 0.85 [0.76, 0.95], P < 0.003). Furthermore, multivariable logistic regression analyses by ethnicity revealed that this association was significant solely among Non-Hispanic Whites (OR = 0.78 [0.68, 0.90], P < 0.001). The area under the ROC curve (AUC) for UA/Cr in predicting OP was higher than that for SUA alone, indicating superior predictive value.

Conclusion

A higher UA/Cr level within the normal range is associated with a lower risk of OP, providing insights for its diagnosis and risk assessment.

Efficacy of acupuncture-related therapy for postmenopausal osteoporosis: a systematic review and network meta-analysis based on randomized controlled trials

Introduction

To compare and analyze the clinical effects of acupuncture-related therapies for postmenopausal osteoporosis (PMOP) and propose the optimal scheme, we utilized a network meta-analysis to evaluate the therapeutic effects of various commonly used acupuncture methods for PMOP.

Methods

Randomized controlled trials of acupuncture-related therapies for PMOP were searched in eight databases (PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure, China Science and Technology Journal Database, China Biomedical Literature Database, and Wanfang database) from January 1, 2002 to December 31, 2023. Our primary outcomes included overall clinical effectiveness rate, bone mineral density (BMD), and visual analog scale scores (VAS). The secondary outcome is adverse events. The entire process of literature screening and data analysis was conducted by 2 independent investigators.

Results

A total of 30 studies with 2,342 participants provided data suitable for analysis. We compared six interventions: manual acupuncture, electroacupuncture, acupoint catgut embedding, moxibustion, acupoint application, and warm acupuncture. The results of the network meta-analysis revealed that, when compared to conventional Western medication (CWM), multiple acupuncture therapies had a greater impact on the overall clinical effectiveness rate. Electroacupuncture combined with CWM demonstrated superior clinical effectiveness and lumbar spine BMD improvement. Moxibustion with CWM ranked highest for femoral neck BMD, while warm acupuncture showed optimal effects on Ward's triangle and trochanter BMD. Acupoint catgut embedding provided the greatest pain reduction. The most prevalent minor adverse effects included hematoma, discomfort, and scorching.

Conclusion

The results suggest that several acupuncture-related therapies, either alone or in conjunction with CWM, outperform CWM alone and may be regarded as an alternative or supplementary therapy to PMOP, though higher-quality trials are needed.

Hormone Replacement Therapy Relieves Periodontitis by Inhibiting Alveolar Bone Loss and Inflammation

OBJECTIVE

Hormone replacement therapy (HRT) is a commonly used strategy for treating menopausal symptoms, while its relation with periodontitis remains unclear. This study aimed to explore the potential effects of HRT on periodontitis, mainly in aspects of bone loss and inflammation.

METHODS

The alveolar bone height (ABH), alveolar bone thickness (ABT), and bone mineral density (BMD) were measured in menopausal women with periodontitis who had received HRT or had not received HRT by cone beam computed tomography. Based on a rat model of periodontitis, the alveolar bone loss was evaluated by micro-computed tomography and bone-related biochemical markers. The expression/levels of inflammatory markers were measured to reflect periodontal inflammation.

RESULTS

Although the differences were not all significant in each premolars/molars, the mesial/distal ABH and buccal/lingual ABT were lower, and the mesial/distal BMD was higher in patients in the HRT group than those in the control group. In a rat model of periodontitis, the alveolar bone loss was relieved by HRT. Additionally, HRT significantly weakened the elevation of inflammatory markers, including TNF-α, IL-1β, and IL-6 in periodontitis rats.

CONCLUSIONS

HRT contributes to the remission of periodontitis by inhibiting alveolar bone loss and inflammation.

Bone Health for Gynaecologists

Osteoporosis, the most common bone disorder, profoundly impacts women's health, especially during postmenopausal phases. Characterised by diminished bone mineral density (BMD), it increases the risk of fractures, affecting mobility, quality of life, and potentially mortality. The present review analyses the intricate interactions among physiological alterations, diseases, and medications that lead to bone mineral density reduction in women. It underscores the importance of gynaecologists in the prevention, diagnosis, and management of osteoporosis via early risk assessment, suitable hormone treatment, and lifestyle modifications. Essential considerations encompass the categorisation of osteoporosis into primary (age-related) and secondary (attributable to diseases or pharmacological treatments) types, with particular emphasis on predisposing conditions such as premature menopause, hormone deficits, and cancer therapies. The significance of diagnostic instruments such as DXA and novel methodologies like trabecular bone score and quantitative ultrasonography is emphasised for precise evaluation and surveillance. The review also addresses nutritional methods, physical exercise, and pharmaceutical interventions, including hormone replacement therapy (HRT), selective oestrogen receptor modulators (SERMs), and other anti-resorptive drugs, to preserve bone health. This review highlights the important role of gynaecologists in maintaining women's bone health, promoting a proactive strategy to avert osteoporosis-related complications and enhance long-term results.

Acute effects of high-intensity interval exercise plus whole-body vibration on bone turnover markers, BDNF, irisin, and neurocognitive performance in postmenopausal women

The acute effects of exercise can elucidate the molecular and psychophysiological mechanisms underlying exercise's benefits in several systems (e.g., the brain, muscle, and bone). In this study, a single 30-minute session of high-intensity interval aerobic exercise (HIIAE) administered in conjunction with isometric resistance exercise on a whole-body vibration (WBV) platform (HIIAE+WBV) was compared with HIIAE alone in their effects on molecular and neurocognitive indices among 63 sedentary, healthy postmenopausal women who were randomly assigned to HIIAE (n = 20), HIIAE+WBV (n = 20), and Control (n = 23) groups. The assessed molecular indices were serum levels of osteocalcin (OC), uncarboxylated OC (ucOC), carboxylated OC (cOC), brain-derived neurotrophic factor (BDNF), and irisin, and the assessed neurocognitive indices were the accuracy rate (AR), reaction time (RT), and electroencephalography event-related potentials (ERPs) of P2 and P3 components in a visuospatial working memory task. Data on these indices before versus after an acute bout of HIIAE or HIIAE+WBV or after a resting session were compared. An HIIAE or HIIAE+WBV intervention yielded no significant change in ERP P2 latency/amplitude and P3 latency but yielded significantly higher ARs, shorter RTs, larger ERP P3 amplitudes, and higher OC, cOC, BDNF, and irisin levels in the postmenopausal women. HIIAE+WBV outperformed HIIAE alone in AR, ucOC, and BDNF. However, the changes in these molecular and neurocognitive indices induced by the two exercise modes did not show any significant correlations in the present study. The present findings suggest that HIIAE and HIIAE+WBV have the potential to acutely influence markers of bone and brain health, with HIIAE+WBV showing greater effectiveness than HIIAE alone. These interventions should be further investigated in future randomized controlled trials involving postmenopausal women.

Relationship between bone mineral density and oral health: a cross sectional observational study

PURPOSE

Bone mineral density (BMD) is related to oral health. This study investigated how changes in BMD influence tooth loss risk and dental caries prevalence.

METHODS

This cross-sectional observational study included 224 people (199 males and 25 females). The BMD scores of the participants' lumbar spine, femoral neck, and total hip were categorized as normal, osteopenia, or osteoporosis. Oral health was assessed using the Decayed, Missing, Filled Teeth (DMFT) index and Oral Hygiene Index-Simplified (OHI-S) scores. Based on the number of surviving teeth, the participants were categorized into low (< 20) and high (≥ 20) groups. Differences between groups were assessed using independent sample T tests and one-way analysis of variance.

RESULTS

The normal, osteopenia, and osteoporosis groups comprised 72, 87, and 65 participants, respectively. The OHI-S scores showed no notable variations across the groups. The DMFT index scores were highest (18.69) in the osteoporosis group and lowest (14.08) in the normal group (p < 0.001). Although the number of remaining teeth was lower in the osteoporosis and osteopenia groups compared to the normal group (p < 0.001), that in the osteopenia group approximated the normal group, but was substantially higher than in the osteoporosis group. The group with the lowest number of remaining teeth had lower total hip T-scores, despite significantly higher DMFT indexes (p < 0.001).

CONCLUSIONS

Tooth loss and dental decay rates were significantly high in patients with osteoporosis. Although bone resorption during osteopenia is not excessive, it constitutes a crucial risk factor for dental health. Therefore, attention must be paid to bone resorption treatment in patients with osteopenia.

Humic Acid Derived from Vermicompost Improves Bone Mineral Content and Alters Oxidative Stress Markers in Ovariectomized Mice

Background: Estrogen depletion alters bone mineralization and oxidative stress. Antioxidants like humic acids (HA) may help mitigate bone demineralization and redox imbalances. Thus, this study evaluated the effects of HA on bone mineral composition and oxidative stress markers in an experimental menopause model. Methods: Twenty-four female C57BL/6 mice were divided into four groups (n = 6/group): Sham; Sham + HA; Ovariectomized (OVX); and OVX + HA. The menopause model was induced by bilateral ovariectomy at the beginning of the experiment. HA derived from biomass vermicompost was administered daily by gavage for 28 days. After euthanasia, femurs and fragments of the gastrocnemius muscle, liver, and kidney were collected. Bone elemental composition was analyzed using scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS). Superoxide dismutase (SOD), catalase (CAT), and hydrogen peroxide (H2O2) activities were assessed in muscle, renal, and hepatic tissues. Data were analyzed using two-way ANOVA and Bonferroni's post hoc test. Results: Untreated OVX mice exhibited a significant reduction in femoral calcium content (p < 0.05). However, HA treatment increased calcium levels and improved the Ca/P ratio (p < 0.05). H2O2 activity was reduced in the liver and kidney of OVX + HA mice compared to untreated animals (p < 0.05). CAT activity in muscle increased in the OVX + HA group compared to the OVX (p < 0.05). Conclusions: HA treatment improved femoral elemental composition and modulated oxidative stress markers in an experimental menopause model.

Evolving strategies for osteoporosis management in postmenopausal women: From tradition to innovation

Osteoporosis is a chronic condition primarily affecting postmenopausal women, significantly impacting their well-being and quality of life. Traditional treatment approaches include medications, vitamins, and exercise, but there is a growing interest in alternative therapies that enhance bone health. This review was conducted by searching multiple databases, including PubMed, Medline, and Google Scholar, for studies related to osteoporosis treatment. Articles focusing on both traditional therapies such as bisphosphonates, calcium, and vitamin D supplementation, and newer advancements like vibration therapy and bone-building devices such as Osteoboost were included. Traditional treatments, such as vitamin supplementation, exercise, and bisphosphonates, remain foundational in osteoporosis management, helping to maintain bone density and reduce fracture risks. Recent developments, including vibration therapy and Osteoboost, show promising results in bone regeneration without the use of medication. While traditional therapies continue to play an essential role, advancements like vibration therapy present novel alternatives for managing osteoporosis. Further research is necessary to optimize these approaches, ensuring they maximize benefits while minimizing risks, ultimately improving patient outcomes and quality of life.

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.

Update on Menopause Hormone Therapy; Current Indications and Unanswered Questions

OBJECTIVE

To provide clinicians involved in managing menopause with a summary of current evidence surrounding menopause hormone therapy (MHT).

DESIGN

The authors evaluate and synthesize existing pooled evidence relating to MHT's clinical indications, efficacy, and safety and explore the limitations of existing data.

PATIENTS

The review focuses on MHT-related outcomes in women with natural-timed menopause captured within observational studies, RCTs, and pooled data from pivotal meta-analyses and reviews.

MEASUREMENTS

Available published data are scrutinized. Available evidence and notably lacking data from women not adequately represented in published MHT trials, such as those with socioeconomic adversity, significant comorbidities, and minority ethnic backgrounds, are highlighted and deliberated.

RESULTS

The impact of MHT differs significantly between demographics. Current consensus recommendations for MHT emphasize the importance of tailoring type, route, dose, and duration of therapy to individual needs and risk/benefit ratio through shared decision-making. MHT impact can change over time. Current MHT data support its benefits for treating menopause symptoms and a potential window of opportunity in midlife to benefit skeletal health. Limitations of current evidence highlight menopause health inequalities and underscores the need for further research.

CONCLUSIONS

This review recommends tailored use of MHT for well-defined indications, recognizing its value for menopause symptom relief and skeletal benefits for many midlife women. MHT may be used as long as benefits outweigh risks, through shared decision-making. There is insufficient clinical evidence to support the long-term use of MHT in some contemporary cohorts of women accessing MHT in clinical practice.

Efficacy and Mechanism of Highly Active Umbilical Cord Mesenchymal Stem Cells in the Treatment of Osteoporosis in Rats

BACKGROUND

Osteoporosis increases bone brittleness and the risk of fracture. Umbilical cord mesenchymal stem cell (UCMSC) treatment is effective, but how to improve the biological activity and clinical efficacy of UCMSCs has not been determined.

METHODS

A rat model of osteoporosis was induced with dexamethasone sodium phosphate. Highly active umbilical cord mesenchymal stem cells (HA-UCMSCs) and UCMSCs were isolated, cultured, identified, and infused intravenously once at a dose of 2.29 × 106 cells/kg. In the 4th week of treatment, bone mineral density (BMD) was evaluated via cross-micro-CT, tibial structure was observed via HE staining, osteogenic differentiation of bone marrow mesenchymal stem cells (BMMSCs) was examined via alizarin red staining, and carboxy-terminal cross-linked telopeptide (CTX), nuclear factor-κβ ligand (RANKL), procollagen type 1 N-terminal propeptide (PINP) and osteoprotegerin (OPG) levels were investigated via enzyme-linked immunosorbent assays (ELISAs). BMMSCs were treated with 10-6 mol/L dexamethasone and cocultured with HA-UCMSCs and UCMSCs in transwells. The osteogenic and adipogenic differentiation of BMMSCs was subsequently examined through directional induction culture. The protein expression levels of WNT, β-catenin, RUNX2, IFN-γ and IL-17 in the bone tissue were measured via Western blotting.

RESULTS

The BMD in the healthy group was higher than that in the model group. Both UCMSCs and HA-UCMSCs exhibited a fusiform morphology; swirling growth; high expression of CD73, CD90 and CD105; and low expression of CD34 and CD45 and could differentiate into adipocytes, osteoblasts and chondrocytes, while HA-UCMSCs were smaller in size; had a higher nuclear percentage; and higher differentiation efficiency. Compared with those in the model group, the BMD increased, the bone structure improved, the trabecular area, number, and perimeter increased, the osteogenic differentiation of BMMSCs increased, RANKL expression decreased, and PINP expression increased after UCMSC and HA-UCMSC treatment for 4 weeks. Furthermore, the BMD, trabecular area, number and perimeter, calcareous nodule counts, and OPG/RANKL ratio were higher in the HA-UCMSC treatment group than in the UCMSC treatment group. The osteogenic and adipogenic differentiation of dexamethasone-treated BMMSCs was enhanced after the coculture of UCMSCs and HA-UCMSCs, and the HA-UCMSC group exhibited better effects than the UCMSC coculture group. The protein expression of WNT, β-catenin, and runx2 was upregulated, and IFN-γ and IL-17 expression was downregulated after UCMSC and HA-UCMSC treatment.

CONCLUSION

HA-UCMSCs have a stronger therapeutic effect on osteoporosis compared with that of UCMSCs. These effects include an improved bone structure, increased BMD, an increased number and perimeter of trabeculae, and enhanced osteogenic differentiation of BMMSCs via activation of the WNT/β-catenin pathway and inhibition of inflammation.

Exploring the effects of estrogen deficiency and aging on organismal homeostasis during menopause

Sex hormone signaling declines during aging, from early midlife through menopause, as a consequence of reduced circulating estrogens and decreased receptiveness to these hormones in target tissues. Estrogens preserve energy homeostasis and promote metabolic health via coordinated and simultaneous effects throughout the brain and body. Age-associated loss of estrogen production during menopause has been implicated in a higher risk for metabolic diseases and increased mortality. However, it remains unclear whether age-associated changes in homeostasis are dependent on reduced estrogen signaling during menopause. Although menopausal hormone therapies containing estrogens can alleviate symptoms, concerns about the risks involved have contributed to a broad decline in the use of these approaches. Non-hormonal therapies have emerged that target tissues or pathways with varying levels of selectivity, reducing risk. We summarize here the broad effects of estrogen loss on homeostasis during menopause, current and emerging therapies and opportunities for understanding homeostatic disruptions associated with menopause.

A natural agent, 5-deoxycajanin, mitigates estrogen-deficiency bone loss via modulating osteoclast-osteoblast homeostasis

Hyperactive osteoclasts and hypoactive osteoblasts usually result in osteolytic conditions such as estrogen-deficiency bone loss. Few natural compounds that both attenuating bone resorption and enhancing bone formation could exert effects on this imbalance. 5-Deoxycajanin (5-D), an isoflavonoid extracted from Cajan leaf with estrogen-like properties, were found to have beneficial pharmacological effects on rebalancing the activities of osteoclasts and osteoblasts. This study revealed that 5-D at the same concentration could inhibit osteoclastogenesis of BMMs and promoted osteoblast differentiation of BMSCs. 5-D not only attenuated the fluorescent formation of RANKL-induced F-actin belts and NFATc1, but also activated ALP and RUNX2 expressions. As to downstream factor expressions, 5-D could block osteoclast-specific genes and proteins including NFATc1 and CTSK, while increased osteogenic genes and proteins including OPG and OCN, as confirmed by Real-time PCR and Western Blotting. Additionally, the network pharmacology and molecular docking identified the involvement of 5-D in the MIF and MAPK signaling pathways and the stable binding between 5-D and MAPK2K1. Further Western blot studies showed that 5-D decreased the phosphorylation of p38 and ERK in osteoclasts, but promoted these phosphorylations in osteoblasts. In a female C57BL/6J mouse model of estrogen deficiency-induced bone loss, 5-D demonstrated efficacy in enhancing BMD through attenuating osteoclast activities and promoting osteogenesis. These results underscore the potential application of 5-D on treating osteolysis resulting from hyperactive osteoclasts and hypoactive osteoblasts, shedding light on modulating osteoclast-osteoblast homeostasis.

Metformin improves HPRT1-targeted purine metabolism and repairs NR4A1-mediated autophagic flux by modulating FoxO1 nucleocytoplasmic shuttling to treat postmenopausal osteoporosis

Osteoporosis is a major degenerative metabolic bone disease that threatens the life and health of postmenopausal women. Owing to limitations in detection methods and prevention strategy awareness, the purpose of osteoporosis treatment is more to delay further deterioration rather than to fundamentally correct bone mass. We aimed to clarify the pathogenesis of postmenopausal osteoporosis and optimize treatment plans. Our experiments were based on previous findings that oxidative stress mediates bone metabolism imbalance after oestrogen deficiency. Through energy metabolism-targeted metabolomics, we revealed that purine metabolism disorder is the main mechanism involved in inducing oxidative damage in bone tissue, which was verified via the use of machine-learning data from human databases. Xanthine and xanthine oxidase were used to treat osteoblasts to construct a purine metabolism disorder model. The activity and differentiation ability of osteoblasts decreased after X/XO treatment. Transcriptomic sequencing indicated that autophagic flux damage was involved in purine metabolism-induced oxidative stress in osteoblasts. Additionally, we performed serum metabolomics combined with network pharmacology to determine the pharmacological mechanism of metformin in the treatment of postmenopausal osteoporosis. HPRT1 was the potential target filtered from the hub genes, and FoxO1 signalling was the key pathway mediating the effect of metformin in osteoblasts. We also revealed that SIRT3-mediated deacetylation promoted the nuclear localization of FoxO1 to increase the expression of HPRT1. HPRT1 upregulation promoted purine anabolism and prevented the accumulation of ROS caused by purine catabolism to reverse oxidative damage in osteoblasts. We propose that purine metabolism disorder-induced oxidative stress is important for the pathogenesis of postmenopausal osteoporosis. The therapeutic mechanism of metformin should be confirmed through subsequent drug optimization and development studies to improve bone health in postmenopausal women.

Catalpol Enhances Osteogenic Differentiation of Human Periodontal Stem Cells and Modulates Periodontal Tissue Remodeling in an Orthodontic Tooth Movement Rat Model

Purpose

This study examines the effects and mechanisms of catalpol (CAT) on the proliferation and osteogenic differentiation of cultured human periodontal ligament stem cells (hPDLSCs) in vitro and assesses the impact of CAT on periodontal remodeling in vivo using an orthodontic tooth movement (OTM) model in rats.

Methods

hPDLSCs were cultured in a laboratory setting, and their proliferation and osteogenic differentiation were assessed using the Cell-counting Kit-8 (CCK-8), Alizarin Red Staining (ARS), quantitative calcium assay, alkaline phosphatase (ALP) staining and activity assay, and immunofluorescence assay. Additionally, the expression of collagen type 1 (COL-1), ALP, and runt-related transcription factor-2 (RUNX-2) was evaluated through qRT-PCR and Western blot analysis. To verify the function of the estrogen receptor-α (ER-α)-mediated phosphatidylinositol-3-kinase-protein kinase B (PI3K/AKT) pathway in this mechanism, LY294002 (a PI3K signaling pathway inhibitor) and the ER-α specific inhibitor methyl-piperidine-pyrazole (MPP) were used. The osteogenic markers ER-α, AKT, and p-AKT (phosphoprotein kinase B) were identified through Western blot analysis. Eighteen male Sprague-Dawley rats were assigned to two groups randomly: a CAT group receiving CAT and a control group receiving an equivalent volume of saline. Micro-computed tomography (micro-CT) analysis was employed to evaluate tooth movement and changes in alveolar bone structure. Morphological changes in the periodontal tissues between the roots were investigated using hematoxylin and eosin (HE) staining and tartaric-resistant acid phosphatase (TRAP) staining. The expression of COL-1, RUNX-2, and nuclear factor-κB (NF-κB) ligand (RANKL) was assessed through immunohistochemical staining (IHC) to evaluate periodontal tissue remodeling. Tests were analyzed using GraphPad Prism 8 software. Differences among more than two groups were analyzed by one-way or two-way analysis of variance (ANOVA) followed by the Tukey's test. Values of p < 0.05 were regarded as statistically significant.

Results

In vitro experiments demonstrated that 10 μM CAT significantly promoted the proliferation, ALP activity, and calcium nodule formation of hPDLSCs, with a notable increase in the expression of COL-1, ALP, RUNX-2, ER-α, and p-AKT. The PI3K/AKT pathway was inhibited by LY294002, and further analysis using MPP suggested that ER-α mediated this effect. In vivo, experiments indicated that CAT enhanced the expression of COL-1 and RUNX-2 on the tension side of rat tooth roots, reduced the number of osteoclasts on the compression side, inhibited RANKL expression, and suppressed OTM.

Conclusion

CAT can promote hPDLSCs proliferation and osteogenic differentiation in vitro through the ER-α/PI3K/AKT pathway and enhance periodontal tissue remodeling in vivo using OTM models. These findings suggest the potential for the clinical application of catalpol in preventing relapse following OTM.

Alcohol use at midlife and in menopause: a narrative review

Alcohol use disorder stands as a prevalent global issue, contributing to 140,000 annual deaths in the United States and causing numerous adverse health and socioeconomic outcomes. Despite being a natural physiological process, menopause often leads to troublesome symptoms that affect women's quality of life and exposes them to increased health risks. Our review delves into the intricate relationship between alcohol use disorder and the menopausal experience. We examine the impact of heightened alcohol consumption on the onset, severity, and burden of menopausal symptoms, particularly vasomotor symptoms. Additionally, we explore its effects on commonly experienced menopausal symptoms such as mood disturbances, sleep problems, and sexual dysfunction. Considering the chronic health conditions associated with both menopause and alcohol use disorder, our study also investigates the influence of alcohol use disorder on bone density. This is especially important due to the elevated risks and mortality linked to bone mineral density loss in menopausal women.

No genetic causal relationship between lung function and osteoporosis - evidence from a mendelian randomization study

For a long time, the decline in lung function has been regarded as a potential factor associated with the risk of osteoporosis (OP). Although several observational studies have investigated the relationship between lung function and OP, their conclusions have been inconsistent. Given that Mendelian randomization (MR) studies can help reduce the interference of confounding factors on outcomes, we adopted this approach to explore the causal relationship between lung function and OP at the genetic level. To investigate the potential causality between lung function (FVC, FEV1, FEV1/FVC, PEF) and OP, we conducted a MR analysis employing three approaches: inverse variance weighted (IVW), MR-Egger, and weighted median. We used Cochran's Q test to detect potential heterogeneity, MR-Egger regression to evaluate directional pleiotropy, and the MR-PRESSO method to evaluate horizontal pleiotropy. In addition, we used MR-PRESSO and MR radial methods to exclude SNPs exhibiting pleiotropic outliers. Upon identification of potential outliers, we removed them and subsequently ran MR analysis again to assess the reliability of our findings. The MR analysis suggested that there was no causal effect of lung function (FVC, PEF, FEV1/FVC, FEV1) on OP, which is consistent with the. results after excluding potential outliers using MR-PRESSO and MR radial. methods. Sensitivity analysis confirmed the reliability and consistency of these. results. The study concluded that there is no causal link between lung function and OP. The association found in observational studies might be attributable to shared risk factors.

ALKBH5 regulates etoposide-induced cellular senescence and osteogenic differentiation in osteoporosis through mediating the m6A modification of VDAC3

Osteoporosis, a common bone disease in older individuals, involves the progression influenced by N6-methyladenosine (m6A) modification. This study aimed to elucidate the effects of VDAC3 m6A modification on human bone mesenchymal stromal cell (BMSC) senescence and osteogenic differentiation. BMSCs were treated with etoposide to induce senescence. Senescence was assessed by β-galactosidase staining and quantitative real-time PCR (qPCR), and osteogenic differentiation was evaluated using Western blot, alkaline phosphatase, and alizarin red S staining. VDAC3 and ALKBH5 expression were quantified by qPCR, and their interaction was assessed by RNA immunoprecipitation (RIP) and luciferase reporter assay. m6A methylation was analyzed using the Me-RIP assay. VDAC3 expression was significantly decreased in etoposide-treated BMSCs (1.00 ± 0.13 vs. 0.26 ± 0.06). VDAC3 overexpression reduced etoposide-induced senescence and promoted osteogenic differentiation. ALKBH5 overexpression inhibited VDAC3 m6A modification (1.00 ± 0.095 vs. 0.233 ± 0.177) and its stability. ALKBH5 knockdown decreased etoposide-induced senescence and promoted osteogenic differentiation, effects that were reversed by VDAC3 knockdown. YTHDF1 was identified as the m6A methylation reader, and its overexpression inhibited VDAC3 stability. We demonstrated that ALKBH5 inhibited osteogenic differentiation of etoposide-induced senescent cells through the inhibition of VDAC3 m6A modification, and YTHDF1 acted as the m6A methylation reader. These findings provide a novel theoretical basis for the treatment of osteoporosis.

Hormone replacement therapy and periodontitis progression in postmenopausal women: A prospective cohort study

OBJECTIVE

This study aimed to investigate the responses of periodontal environment to hormone replacement therapy (HRT) in postmenopausal women with or without periodontitis.

BACKGROUND

HRT is a common and effective strategy for controlling menopausal symptoms, while the changes of periodontal environment under it, particularly in postmenopausal women with periodontitis, remain unclear.

METHODS

As a prospective cohort study, a total of 97 postmenopausal women receiving HRT were screened, including 47 with and 50 without periodontitis. Correspondingly, 97 women did not receiving HRT were screened as controls during the same period. The full-mouth sulcus bleeding index (SBI), bleeding on probing (BOP), probing pocket depth (PPD), and clinical attachment level (CAL) were measured using periodontal probes. The levels of interleukin-6 (IL-6) and tumor necrosis factor α (TNF-α) in the gingival crevicular fluid were measured using enzyme-linked immunosorbent assay. In addition, cone beam computed tomography was performed to measure the alveolar bone height (ABH) and bone mineral density (BMD).

RESULTS

In postmenopausal women without periodontitis, no significantly changes on periodontal parameters were observed after HRT. In women with stage II periodontitis, SBI, BOP, IL-6, and TNF-α were significant decreased after one year and two years of HRT. Compared to the controls, women with stage II periodontitis who underwent HRT had significantly lower CAL and ABH and higher BMD in the second year. The incidence of at least one site with CAL increase ≥1 mm between baseline and 2 years was significantly lower in the HRT group than in the control group in women with stage II periodontitis. In addition, HRT was significantly associated with a decrease in SBI, BOP, IL-6, and TNF-α in the first year and with a decrease in CAL, SBI, BOP, IL-6, and ABH and an increase in BMD in the second year.

CONCLUSIONS

In postmenopausal women with stage II periodontitis, HRT is associated with the alleviation of inflammation within two years and the remission of alveolar bone loss in the second year. HRT appears to decrease the incidence of CAL increase ≥1 mm within 2 years in women with periodontitis by inhibiting inflammation and alveolar bone loss.

The effects of simvastatin on the bone microstructure and mechanics of ovariectomized mice: a micro-CT and micro-finite element analysis study

BACKGROUND

Osteoporosis is a major health concern for postmenopausal women, and the effect of simvastatin (Sim) on bone metabolism is controversial. This study aimed to investigate the effect of simvastatin on the bone microstructure and bone mechanical properties in ovariectomized (OVX) mice.

METHODS

24 female C57BL/6J mice (8-week-old) were randomly allocated into three groups including the OVX + Sim group, the OVX group and the control group. At 8 weeks after operation, the L4 vertebral bones were dissected completely for micro-Computed Tomography (micro-CT) scanning and micro-finite element analysis (µFEA). The differences between three groups were compared using ANOVA with a LSD correction, and the relationship between bone microstructure and mechanical properties was analyzed using linear regression.

RESULTS

Bone volume fraction, trabecular number, connectivity density and trabecular tissue mineral density in the OVX + Sim group were significantly higher than those in the OVX group (P < 0.05). For the mechanical properties detected via µFEA, the OVX + Sim group had lower total deformation, equivalent elastic strain and equivalent stress compared to the OVX group (P < 0.05). In the three groups, the mechanical parameters were significantly correlated with bone volume fraction and trabecular bone mineral density.

CONCLUSIONS

The findings suggested that simvastatin had a potential role in the treatment of osteoporosis. The results of this study could guide future research on simvastatin and support the development of simvastatin-based treatments to improve bone health.

The Efficacy of Manual Therapy on Musculoskeletal Pain in Menopause: A Systematic Review

(1) Background: The aim of this review was to evaluate the effects of manual therapy for musculoskeletal pain in menopausal women. (2) Methods: A comprehensive search of manuscripts published from inception until 29 February 2024 was conducted on PubMed, EBSCO Information Services (EBSCOhost), Physiotherapy Evidence Database (Pedro), Web of Science, Scientific Electronic Library Online (SciELO), Cochrane Central Register of Controlled Clinical Trials, and Scopus using Medical Subject Headings (MeSH) and free terms. Randomized controlled trials (RCT) investigating the effects of manual therapy for musculoskeletal pain in postmenopausal women were included. Articles published in non-English or non-Portuguese languages, case reports, expert opinions, dissertations, conference papers, and gray literature were excluded. Studies were screened for population, musculoskeletal pain, intervention, and pain outcome by two independent reviewers using an ad hoc data extraction form. (3) Results: A total of 5 RCTs (4 with high risk of bias and 1 with low risk of bias) were included (total sample = 245), addressing thumb carpometacarpal osteoarthritis, thoracic kyphosis, chronic neck and backache, knee osteoarthritis, and sternocostal joint pain. The combined results of these studies showed improved musculoskeletal pain in menopausal women; duration of the follow-up was between 4 weeks to 6 months. Conclusions: The majority of studies included in this systematic review were effective in reducing musculoskeletal pain in menopausal women. These results come mainly from studies with a high risk of bias with small sample sizes, and the most representative follow-up period was short-term. Therefore, the results of this systematic review should be interpreted with caution.

Effect of Tai Chi exercise on bone health and fall prevention in postmenopausal women: a meta-analysis

BACKGROUND

The bone status of postmenopausal women is worsening. In fact, postmenopausal period is the high incidence stage of osteoporosis and falls. Notably, a recent study has pointed out that exercise can improve bone health in postmenopausal women. However, the effect of Tai Chi exercise on postmenopausal women is controversial. Therefore, a meta-analysis was designed to analyze the effect of Tai Chi exercise on bone health and fall prevention in postmenopausal women.

METHODS

The researches on Tai Chi improving the bone health of postmenopausal women before August 31, 2023 were collected from Chinese and English databases, such as PubMed, Embase, and Web of Science, etc. The risk of bias of the included studies was assessed using the Cochrane risk-of-bias tool for randomized trials. Besides, R software 4.3.1 was employed to analyze the effect sizes in the meta-analysis to summarize the impact of Tai Chi on vertebral bone mineral density, serum calcium, clinical balance scores, the number of falls, total falls, and health status scores in postmenopausal women.

RESULTS

There were 12 studies eventually included in this meta-analysis. A total of 1,272 postmenopausal women were involved, including 628 in the experimental group (intervention with Tai Chi exercise) and 644 in the control group (without any intervention). Briefly, postmenopausal women practicing Tai Chi presented a significant increase in vertebral bone density [standardized mean difference (SMD) = 0.37, 95% confidence interval (CI) (0.04-0.71), P = 0.03] and health status score [SMD = 0.25, 95% CI (0.01-0.49), P = 0.04]. In contrast, there were no significant differences for postmenopausal women between the two groups in terms of serum calcium [SMD = -0.01, 95% CI (-0.39, 0.36), P = 0.77], clinical balance [SMD = 0.17, 95% CI (-0.01, 0.46), P = 0.23], number of falls [SMD = -0.61, 95% CI (-1.24, 0.02), P = 0.06] and total falls [odds ratio = 0.35, 95% CI (0.11-1.12), P = 0.07].

CONCLUSION

Tai Chi exercise can improve the bone mineral density of postmenopausal women, thereby maintaining bone health. Hence, Tai Chi exercise is necessary to prevent osteoporosis.

Alleviation of Menopausal Symptoms by Yam (Dioscorea japonica Thunb.) and Gromwell (Lithospermum erythrorhizon Sieb. Et Zucc.) Extracts in Ovariectomized Mice

SCOPE

The decline in estrogen during menopause contributes to a variety of menopausal symptoms, for which hormone replacement therapy (HRT) has been extensively applied. Regarding side effects and limited effectiveness of HRT for specific individuals, there is a growing interest in safe alternatives such as phytoestrogens which are structurally analogous to estrogens. This study aims to investigate the efficacy of yam and gromwell extracts, rich in bioactive compounds, and the synergistic effect of extracts on symptoms induced by estrogen deficiency in ovariectomized (OVX) mice.

METHODS AND RESULTS

OVX mice receive dietary intervention of either yam, gromwell extract, or their mixture for 14 weeks. Sham-operated mice and E2-injected OVX mice serve as positive controls. Following 14 weeks of oral administration, blood, adipose tissue, vagina, uterus, femurs, and tibias are harvested for further investigation. Consequently, yam and gromwell extracts ameliorate menopausal conditions such as weight gain, glucose intolerance, dyslipidemia, and osteoporosis in estrogen-deficient OVX mice. In addition, the mixture of yam and gromwell extracts synergistically aids in the relief of the indications.

CONCLUSION

These results indicate the potential use of yam and gromwell extracts, as well as their mixture, for the development of healthy functional foods to modulate menopausal symptoms.

Quercetin ameliorates bone loss in OVX rats by modulating the intestinal flora-SCFAs-inflammatory signaling axis

BACKGROUND

Osteoporosis (OP) is a common systemic skeletal disorder characterized by an imbalance in bone homeostasis, involving increased osteoclastic bone formation and decreased osteoblastic bone resorption. Quercetin is a plant polyphenol that has been found to exhibit various biological activities, including antioxidant, anti-inflammatory, and antimicrobial effects. Previous studies have demonstrated its potential to improve postmenopausal OP, although the exact mechanism remains unclear. This study aims to investigate the anti-osteoporotic mechanism of quercetin based on the "intestinal flora - short-chain fatty acids (SCFAs) - inflammatory" signaling axis.

METHODS

In this study, we established an ovariectomized (OVX)-induced rat model, quercetin intervention and evaluated the effects on rats following antibiotic (ABX) treatment and fecal microbiota transplantation (FMT). After 6 weeks of intervention, the rats were euthanized, and samples from their femur, tibia, lumbar spine, serum, colon and feces were collected, and bone strength, intestinal flora structure, SCFAs levels and cytokine levels were assessed.

RESULTS

Quercetin modulates the intestinal flora by increasing potentially probiotic bacteria (i.e., Lactobacillales, Prevotellaceae, and Blautia) and decreasing potentially pathogenic bacteria (Desulfobacterota, Erysipelotrichales, Romboutsia, and Butyricoccaceae). It also increases SCFAs content and reduces colonic permeability by enhancing tight junction proteins (ZO-1, Occludin). Furthermore, quercetin lowers proinflammatory cytokine levels (LPS, IL-1β, and TNF-α), which enhances bone strength and prevents OVX-induced bone loss.

CONCLUSIONS

Quercetin may effectively reduce bone loss in OVX rats via the "intestinal flora - SCFAs - inflammatory" signaling pathway.

Clinical challenges and considerations in pharmacotherapy of osteoporosis due to menopause

INTRODUCTION

Osteoporosis is a chronic systemic skeletal disorder characterized by compromised bone strength and an increased risk of fracture, with a high prevalence worldwide. It is associated with a negative quality of life and an increased morbidity and mortality. Postmenopausal women are more prone to develop osteoporosis, and many of them will suffer at least one fragility fracture along their lifetime.

AREAS COVERED

This review starts by summarizing the pathogenesis of postmenopausal osteoporosis (PMO), with focus on the estrogen deficiency-associated bone loss. It continues with the current PMO diagnostic and fracture risk prediction tools, and it finally addresses management of PMO. All the efficacy and safety profiles of the current and future osteoporosis medications are reviewed. Furthermore, strategies to optimize the long-term disease management are discussed. For this review, only publications in English language were selected. References were extracted from PubMed, Embase, and Medline.

EXPERT OPINION

PMO disease management is far from being ideal. Educational and communication programs with the goal of improving disease knowledge and awareness, as well as reducing the health-care gap, should be implemented. In addition, most effective sequential prevention and treatment strategies should be initiated from the early menopause.

The Bioactive Compounds of Epimedium and Their Potential Mechanism of Action in Treating Osteoporosis: A Network Pharmacology and Experimental Validation Study

Osteoporosis is a global health challenge characterized by bone loss and microstructure deterioration, which urgently requires the development of safer and more effective treatments due to the significant adverse effects and limitations of existing drugs for long-term treatment. Traditional Chinese medicine, like Epimedium, offers fewer side effects and has been used to treat osteoporosis, yet its active compounds and pharmacological mechanisms remain unclear. In this study, 65 potential active compounds, 258 potential target proteins, and 488 pathways of Epimedium were identified through network pharmacology analysis. Further network analysis and review of the literature identified six potential active compounds and HIF-1α for subsequent experimental validation. In vitro experiments confirmed that 2″-O-RhamnosylIcariside II is the most effective compound among the six potential active compounds. It can promote osteoblast differentiation, bind with HIF-1α, and inhibit both HIF-1α gene and protein expression, as well as enhance COL1A1 protein expression under hypoxic conditions. In vivo experiments demonstrated its ability to improve bone microstructures and reduce bone loss by decreasing bone marrow adipose tissue, enhancing bone formation, and suppressing HIF-1α protein expression. This study is the first to describe the therapeutic effects of 2-O-RhamnosylIcariside II on osteoporosis, which was done, specifically, through a mechanism that targets and inhibits HIF-1α. This study provides a scientific basis for the clinical application of Epimedium and offers a new candidate drug for the treatment of osteoporosis. Additionally, it provides new evidence supporting HIF-1α as a therapeutic target for osteoporosis.

CircCOX6A1 suppresses osteogenic differentiation and aggravates osteoporosis via miR-512-3p/DYRK2 axis

BACKGROUND

Osteoporosis (OP), characterized by compromised bone integrity and increased fracture risk, poses a significant health challenge. Circular RNAs (circRNAs) have emerged as crucial regulators in various pathophysiological processes, prompting investigation into their role in osteoporosis. This study aimed to elucidate the involvement of circCOX6A1 in OP progression and understand its underlying molecular mechanisms. The primary objective was to explore the impact of circCOX6A1 on bone marrow-derived mesenchymal stem cells (BMSCs) and its potential interactions with miR-512-3p and DYRK2.

METHODS

GSE161361 microarray analysis was employed to assess circCOX6A1 expression in OP patients. We utilized in vitro and in vivo models, including BMSC cultures, osteogenic differentiation assays, and an OVX-induced mouse model of OP. Molecular techniques such as quantitative RT-PCR, western blotting, and functional assays like alizarin red staining (ARS) were employed to evaluate circCOX6A1 effects on BMSC proliferation, apoptosis, and osteogenic differentiation. The interaction between circCOX6A1, miR-512-3p, and DYRK2 was investigated through dual luciferase reporter assays, RNA immunoprecipitation, and RNA pull-down assays.

RESULTS

CircCOX6A1 was found to be upregulated in osteoporosis patients, and its expression inversely correlated with osteogenic differentiation of BMSCs. CircCOX6A1 knockdown enhanced osteogenic differentiation, as evidenced by increased mineralized nodule formation and upregulation of osteogenic markers. In vivo, circCOX6A1 knockdown ameliorated osteoporosis progression in OVX mice. Mechanistically, circCOX6A1 acted as a sponge for miR-512-3p, subsequently regulating DYRK2 expression.

CONCLUSION

This study provides compelling evidence for the role of circCOX6A1 in osteoporosis pathogenesis. CircCOX6A1 negatively regulates BMSC osteogenic differentiation through the miR-512-3p/DYRK2 axis, suggesting its potential as a therapeutic target for mitigating OP progression.

ED-71 Improves Bone Mass in Ovariectomized Rats by Inhibiting Osteoclastogenesis Through EphrinB2-EphB4-RANKL/OPG Axis

Purpose

Estrogen deficiency is the main reason of postmenopausal osteoporosis. Eldecalcitol (ED-71) is a new active vitamin D analogue clinically used in the treatment of postmenopausal osteoporosis. We aimed to investigate whether EphrinB2-EphB4 and RANKL/RANK/OPG signaling cooperate in mediating the process of osteoporosis by ED-71.

Methods

In vivo, the ovariectomized (OVX) rats were administered orally with 30 ng/kg ED-71 once a day for 8 weeks. HE staining, Masson staining and Immunofluorescence staining were used to evaluate bone mass, bone formation, osteoclastogenesis associated factors and the expression of EphrinB2, EphB4, RANKL and OPG. In vitro, H2O2 stimulation was used to simulate the cell environment in osteoporosis. Immunofluorescence, quantitative real time PCR (qRT-PCR), enzyme-linked immunosorbent assay (ELISA) and Western Blot were applied to detect the expression of EphrinB2, EphB4, RANKL and OPG. In osteoblasts, EphB4 was knocked down by EphB4 small-interfering RNA (siRNA) transfection. LY294002 (PI3K inhibitor) or ARQ092 (AKT inhibitor) was used to block PI3K/AKT pathway. An indirect co-culture system of osteoblasts and osteoclasts was established. The mRNA and protein expression of osteoclastogenes is associated factors were tested by qRT-PCR and Western Blot.

Results

ED-71 increased bone mass and decreased the number of osteoclasts in OVX rats. Moreover, ED-71 promoted the expression of EphrinB2, EphB4, and decreased the RANKL/OPG ratio in osteoblasts. Osteoclastogenesis was restrained when osteoclasts were indirectly co-cultured with ED-71-treated osteoblasts. After silencing of EphB4 expression in osteoblasts, ED-71 inhibited the expression of P-PI3K and P-AKT and increased the ratio of RANKL/OPG. This reversed the inhibitory effect of ED-71 on osteoclastogenes. Therefore, in ED-71-inhibited osteoclastogenes, EphB4 is a key factor affecting the secretion of RANKL and OPG by osteoblasts. EphB4 suppressed the RANKL/OPG ratio through activating PI3K/AKT signaling in osteoblasts.

Conclusion

ED-71 inhibits osteoclastogenesis through EphrinB2-EphB4-RANKL/OPG axis, improving bone mass in ovariectomized rats. PI3K/AKT pathway is involved this process.

Neferine alleviates ovariectomy-induced osteoporosis by enhancing osteogenic differentiation of bone marrow mesenchymal stem cells via regulation of the p38MAPK pathway

OBJECTIVE

Osteoporosis, a skeletal ailment marked by bone metabolism imbalance and disruption of bone microarchitecture, Neferine, a bisbenzylisoquinoline alkaloid with diverse pharmacological activities, has received limited attention in the context of osteoporosis treatment.

METHODS

We employed a bilateral ovariectomy (OVX) rat model to induce osteoporosis and subsequently administered Neferine treatment for four weeks following successful model establishment. Throughout the modeling and treatment phases, we closely monitored rat body weights. We assessed alterations in bone tissue microstructure through micro-CT, HE staining, and safranin O-fast green staining. Levels of bone formation and resorption markers in serum were evaluated using ELISA assay. Western blot analysis was employed to determine the expression levels of p38MAPK, p-p38MAPK, and bone formation-related genes in bone tissue. We isolated and cultured OVX rat BMSCs (OVX-BMSCs) and induced osteogenic differentiation while simultaneously introducing Neferine and the p38MAPK inhibitor SB203580 for intervention.

RESULTS

Neferine treatment effectively curbed the rapid weight gain in OVX rats, ameliorated bone loss, and decreased serum levels of TRAP, CTX-I, PINP, and BALP. Most notably, Neferine promoted the expression of bone formation-related factors in bone tissue of OVX rats, while concurrently activating the p38MAPK signaling pathway. In in vitro experiments, Neferine facilitated the expression of bone formation-related factors in OVX-BMSCs, increased the osteogenic differentiation potential of OVX-BMSCs, and activated the p38MAPK signaling pathway. Nevertheless, SB203580 partially reversed Neferine's promotive effect.

CONCLUSION

Neferine can boost the osteoblastic differentiation of BMSCs and alleviate OVX-induced osteoporosis in rats by activating the p38MAPK signaling pathway.

Relationship between menopausal hormone therapy and incidence of fractures in postmenopausal women

OBJECTIVE

Long-term protective effects of menopausal hormone therapy (MHT) at fractures with different doses and components are controversial. We analyzed the effect of MHT on the incidence of spine and femur fractures according to MHT type, age at commencement, duration and dose of hormones in Korean women.

METHOD

This retrospective study evaluated propensity score-matched patients with MHT from the Korean National Health Insurance Service database. Among women aged ≥50 years with menopause between 2004 and 2007, spine and femur fracture incidence until 2017 was analyzed in 36,446 women who had received MHT for >1 year. Estrogen-progesterone therapy (EPT), estrogen-only therapy (ET) or tibolone therapy was conducted.

RESULTS

EPT significantly lowered the incidence of spine and femur fractures with a conventional dose, but not with a low dose. Tibolone significantly decreased the incidence of spine fractures in women aged 50-59 years when used for >5 years, and the incidence of femur fractures in women older than 60 years when used for >3 years. ET significantly lowered the risk of femur fractures when estradiol was used for >5 years.

CONCLUSION

In menopausal women, all MHT including conventional-dose EPT, ET and tibolone tended to lower the incidence of fractures. The effects, however, varied with the type of fracture and type of MHT.

A novel mechanism of Vildagliptin in regulating bone metabolism and mitigating osteoporosis

Osteoporosis has become a global social problem with the tendency toward the aging population. The challenge in managing osteoporosis is to develop new anti-osteoporosis drugs that target bone anabolism. The purpose of this study was to uncover the novel mechanism of Vildagliptin on bone metabolism. We revealed that Vildagliptin significantly promoted osteogenic differentiation of precursor osteoblasts and bone marrow mesenchymal stem cells (BMSCs). At the same time, it significantly enhanced the polarization of RAW264.7 macrophages to the M2 type and the secretion of osteogenic factors BMP2 and TGF-β1. This was confirmed by the increased osteogenic differentiation observed in the osteoblast-RAW264.7 co-culture system. Moreover, Vildagliptin significantly enhanced the transformation of BMSCs into the osteogenic morphology in the osteoblast-BMSC co-culture system. Finally, Vildagliptin also inhibited osteoclastic differentiation of RAW 264.7 cells. The potential mechanism underlying these effects involved targeting the GAS6/AXL/ERK5 pathway. In the in vivo study, Vildagliptin significantly alleviated postmenopausal osteoporosis in ovariectomized mice. These findings represent the first comprehensive revelation of the regulatory effect of Vildagliptin on bone metabolism. Specifically, Vildagliptin demonstrates the ability to promote bone anabolism and inhibit bone resorption by simultaneously targeting osteoblasts, BMSCs, and osteoclasts. The bone-protective effects of Vildagliptin were further confirmed in a postmenopausal osteoporosis model. The clinical significance of this study lies in laying a theoretical foundation for bone protection therapy in type-2 diabetes patients with compromised bone conditions or postmenopausal osteoporosis.

Network pharmacology analysis and experimental validation to explore the mechanism of kaempferol in the treatment of osteoporosis

Osteoporosis (OP) is a prevalent global disease characterized by bone mass loss and microstructural destruction, resulting in increased bone fragility and fracture susceptibility. Our study aims to investigate the potential of kaempferol in preventing and treating OP through a combination of network pharmacology and molecular experiments. Kaempferol and OP-related targets were retrieved from the public database. A protein-protein interaction (PPI) network of common targets was constructed using the STRING database and visualized with Cytoscape 3.9.1 software. Enrichment analyses for GO and KEGG of potential therapeutic targets were conducted using the Hiplot platform. Molecular docking was performed using Molecular operating environment (MOE) software, and cell experiments were conducted to validate the mechanism of kaempferol in treating OP. Network pharmacology analysis identified 54 overlapping targets between kaempferol and OP, with 10 core targets identified. The primarily enriched pathways included atherosclerosis-related signaling pathways, the AGE/RAGE signaling pathway, and the TNF signaling pathway. Molecular docking results indicated stable binding of kaempferol and two target proteins, AKT1 and MMP9. In vitro cell experiments demonstrated significant upregulation of AKT1 expression in MC3T3-E1 cells (p < 0.001) with kaempferol treatment, along with downregulation of MMP9 expression (p < 0.05) compared to the control group. This study predicted the core targets and pathways of kaempferol in OP treatment using network pharmacology, and validated these findings through in vitro experiments, suggesting a promising avenue for future clinical treatment of OP.

Oral Milk-Derived Extracellular Vesicles Inhibit Osteoclastogenesis and Ameliorate Bone Loss in Ovariectomized Mice by Improving Gut Microbiota

Milk-derived extracellular vesicles can improve intestinal health and have antiosteoporosis potential. In this paper, we explored the effects of bovine raw milk-derived extracellular vesicles (mEVs) on ovariectomized (OVX) osteoporotic mice from the perspective of the gut-bone axis. mEVs could inhibit osteoclast differentiation and improve microarchitecture. The level of osteoporotic biomarkers in OVX mice was restored after the mEVs intervened. Compared with OVX mice, mEVs could enhance intestinal permeability, reduce endotoxin levels, and improve the expression of TNF-α, IL-17, and IL-10. 16S rDNA sequencing indicated that mEVs altered the composition of gut microbiota, specifically for Bacteroides associated with short-chain fatty acids (SCFAs). In-depth analysis of SCFAs demonstrated that mEVs could restore acetic acid, propionic acid, valeric acid, and isovaleric acid levels in OVX mice. Correlation analysis revealed that changed gut microbiota and SCFAs were significantly associated with gut inflammation and osteoporotic biomarkers. This study demonstrated that mEVs could inhibit osteoclast differentiation and improve osteoporosis by reshaping the gut microbiota, increasing SCFAs, and decreasing the level of pro-inflammatory cytokines and osteoclast differentiation-related factors in OVX mice. These findings provide evidence for the use of mEVs as a food supplement for osteoporosis.

A systematic review of community pharmacy interventions to improve peri- and post-menopausal health

Menopause is defined as the permanent cessation of menstruation due to loss of ovarian follicular function. Symptoms include mood disorders, vaginal atrophy, hot flashes and night sweats and can emerge during a gradual transition period called perimenopause. Community pharmacies are well placed to deliver a wide range of healthcare services, including supporting and educating menopausal women; however, to date, no systematic review has assessed the effectiveness of community pharmacy-led interventions in improving peri- and post-menopausal health. In accordance with PRISMA guidelines we evaluated community pharmacy-led interventions that targeted women in peri- or post-menopause. Electronic searches in EMBASE, MEDLINE, CINAHL and Cochrane Library were conducted on 13th February 2023. Additionally, we examined the included studies references and citation lists using Google Scholar. A total of 915 articles were identified and screened against the inclusion criteria. Two studies were included; one identified post-menopausal women at risk of developing osteoporosis (OP), and one evaluated the outcomes of a community pharmacy-based menopause education programme. Study one found 11 (11%) post-menopausal women were at risk of developing OP based on quantitative ultrasound screening offered by community pharmacists and referred to their physician. Study two reported that women had access to adequate personalised menopause counselling and increased knowledge of menopause topics because of the educational programme within community pharmacies. Both studies were of low quality. The lack of included studies reflects the need for high-quality research to determine whether community pharmacy-led interventions are feasible, effective and acceptable, to improve health outcomes of peri- or post-menopausal women.

Insights and implications of sexual dimorphism in osteoporosis

Osteoporosis, a metabolic bone disease characterized by low bone mineral density and deterioration of bone microarchitecture, has led to a high risk of fatal osteoporotic fractures worldwide. Accumulating evidence has revealed that sexual dimorphism is a notable feature of osteoporosis, with sex-specific differences in epidemiology and pathogenesis. Specifically, females are more susceptible than males to osteoporosis, while males are more prone to disability or death from the disease. To date, sex chromosome abnormalities and steroid hormones have been proven to contribute greatly to sexual dimorphism in osteoporosis by regulating the functions of bone cells. Understanding the sex-specific differences in osteoporosis and its related complications is essential for improving treatment strategies tailored to women and men. This literature review focuses on the mechanisms underlying sexual dimorphism in osteoporosis, mainly in a population of aging patients, chronic glucocorticoid administration, and diabetes. Moreover, we highlight the implications of sexual dimorphism for developing therapeutics and preventive strategies and screening approaches tailored to women and men. Additionally, the challenges in translating bench research to bedside treatments and future directions to overcome these obstacles will be discussed.

Cardiovascular safety of zoledronic acid in the treatment of primary osteoporosis: A meta-analysis and systematic review

PURPOSE

Osteoporosis is intimately linked to cardiovascular disease and it has been uncertain that zoledronic acid is not correlated with cardiovascular disease. We intended to assess the cardiovascular safety of zoledronic acid in the treatment of primary osteoporosis.

METHODS

We included only randomized controlled trials (RCTs) of patients with osteoporosis receiving zoledronic acid or a placebo. We systematically searched PubMed, Embase, Web of Science, Cochrane CENTRAL, Scopus, the Chinese National Knowledge Infrastructure, ClinicalTrials.gov, and ICTRP from the time of database creation to April 5, 2023. Two investigators extracted data independently on study characteristics, outcomes of interest, and risk of bias based on PRISMA guidelines.

RESULTS

As of April 5, 2023, our search identified 32,361 records, and after excluding these records, 9 RCTs were included in the meta-analysis. The overall risk ratio for cardiovascular events with zoledronic acid for primary osteoporosis compared with placebo was 1.15 (95 % CI 1.05-1.26, I2=12 %, P = 0.002), while the risk of major adverse cardiovascular events with zoledronic acid (RR 1.03, 95 % CI 0. 89-1.18, I2=21 %, P = 0.71) was not significant, possibly due to atrial fibrillation (RR 1.21, 95 % CI 0.99-1.47, I2=0 %, P = 0.06) versus the increased relative risk of arrhythmia (RR 1.30, 95 % CI 1.11-1.52, I2=34 %, P = 0.001). Overall, the cardiovascular risk of zoledronic acid for the treatment of primary osteoporosis was not significant; however, the relative risk of elevated atrial fibrillation and arrhythmias remains to be further studied.

CONCLUSIONS

In women with primary osteoporosis, zoledronic acid may increase the risk of atrial fibrillation (P = 0.06) and arrhythmias (P = 0.001) compared with placebo, independent of the risk of major adverse cardiovascular events, angina, and heart failure. However, the sample size of men with primary osteoporosis is small, and the cardiovascular risk of zoledronic acid in men with osteoporosis is uncertain.

Research progress of targeted therapy regulating Th17/Treg balance in bone immune diseases

Rheumatoid arthritis (RA) and postmenopausal osteoporosis (PMOP) are common bone-immune diseases. The imbalance between helper (Th17) and regulatory T cells (Tregs) produced during differentiation of CD4+ T cells plays a key regulatory role in bone remodelling disorders in RA and PMOP. However, the specific regulatory mechanism of this imbalance in bone remodelling in RA and PMOP has not been clarified. Identifying the regulatory mechanism underlying the Th17/Treg imbalance in RA and PMOP during bone remodelling represents a key factor in the research and development of new drugs for bone immune diseases. In this review, the potential roles of Th17, Treg, and Th17/Treg imbalance in regulating bone remodelling in RA and PMOP have been summarised, and the potential mechanisms by which probiotics, traditional Chinese medicine compounds, and monomers maintain bone remodelling by regulating the Th17/Treg balance are expounded. The maintenance of Th17/Treg balance could be considered as an therapeutic alternative for the treatment of RA and PMOP. This study also summarizes the advantages and disadvantages of conventional treatments and the quality of life and rehabilitation of patients with RA and PMOP. The findings presented her will provide a better understanding of the close relationship between bone immunity and bone remodelling in chronic bone diseases and new ideas for future research, prevention, and treatment of bone immune diseases.

Attenuative effects of collagen peptide from milkfish (Chanos chanos) scales on ovariectomy-induced osteoporosis

Osteoporosis is characterized by low bone mass, bone microarchitecture disruption, and collagen loss, leading to increased fracture risk. In the current study, collagen peptides were extracted from milkfish scales (MS) to develop potential therapeutic candidates for osteoporosis. MS was used to synthesize a crude extract of fish scales (FS), collagen liquid (COL), and hydroxyapatite powder (HA). COL samples were further categorized according to the peptide size of total COL (0.1 mg/mL), COL < 1 kDa (0.1 mg/mL), COL: 1-10 kDa (0.1 mg/mL), and COL > 10 kDa (0.1 mg/mL) to determine it. Semi-quantitative reverse transcription polymerase chain reaction (sqRT-PCR) and immunofluorescence labeling were used to assess the expression levels of specific mRNA and proteins in vitro. For in vivo studies, mice ovariectomy (OVX)-induced postmenopausal osteoporosis were developed, while the sham surgery (Sham) group was treated as a control. Collagen peptides (CP) from MS inhibited osteoclast differentiation in RAW264.7 cells following an insult with nuclear factor kappa-B ligand (RANKL). CP also enhanced osteoblast proliferation in MG-63 cells, possibly through downregulating NFATc1 and TRAP mRNA expression and upregulating ALP and OPG mRNA levels. Furthermore, COL1 kDa also inhibited bone density loss in osteoporotic mice. Taken together, CP may reduce RANKL-induced osteoclast activity while promoting osteoblast synthesis, and therefore may act as a potential therapeutic agent for the prevention and control of osteoporosis.

Comparative efficacy of acupuncture-related therapy for postmenopausal osteoporosis: protocol for Bayesian network meta-analysis

INTRODUCTION

The review aims to conduct the first network meta-analysis to comprehensively evaluate the application of multiple acupuncture techniques in patients with postmenopausal osteoporosis, ranking the best acupuncture treatment and providing a reference for clinical treatment extensively.

METHODS AND ANALYSIS

Randomised controlled trials of different acupuncture-related therapies for postmenopausal osteoporosis will be searched in the following databases from 1 January 2002 to 31 December 2022, including PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure, VIP Database, Wanfang Database and China Biomedical Literature Database. Overall, clinical efficacy rate, bone mineral density and a Visual Analogue Scale score are used as the primary outcome indicators. In addition, the secondary outcome indicator is adverse reactions. The entire screening process will be conducted by two independent investigators; meanwhile, Stata (V.14.0) and RevMan (V.5.4) will be used to conduct the network meta-analysis. If the data are permissible and feasible, we will also perform meta-regression and subgroup analyses to address the underlying causes of data inconsistency and heterogeneity in the statistical analyses. Besides, to improve the credibility of this network meta-analysis, we will evaluate the quality of evidence in this research according to the GRADE assessment.

ETHICS AND DISSEMINATION

Ethics approval is not required for network meta-analyses, which do not involve animals' or people's welfare. The results of this network meta-analysis will be submitted to a recognised journal for publication.

PROSPERO REGISTRATION NUMBER

CRD42023401003.

Role of menopausal hormone therapy in the prevention of postmenopausal osteoporosis

The use of menopausal hormone therapy (MHT) has declined due to concerns about its potential side effects. However, its pivotal role in managing postmenopausal osteoporosis is gaining increased recognition. In this article, we explore how MHT assists postmenopausal women in maintaining bone health and preventing fractures. Recent research indicates that MHT significantly reduces the risk of fractures in women. This benefit is evident regardless of a woman's bone mineral density or their use of progestogens. However, there is limited evidence suggesting that the skeletal benefits continue once the treatment is discontinued. Possible complications of MHT include heart attacks, clots, strokes, dementia, and breast cancer. The most suitable candidates for MHT are women who have recently entered menopause, are experiencing menopausal symptoms, and are below 60 years of age with a minimal baseline risk of adverse events. The treatment is available to those who meet these criteria. For women undergoing premature menopause, MHT can be considered as a means to protect bone health, especially if initiated before menopause or if accelerated bone loss is documented soon after menopause. Such decisions should be made after evaluating individual risk factors and benefits.

Biologics: Teriparatide and Newer Anabolics

The landscape of osteoporosis management has evolved significantly over the years, witnessing a paradigm shift from conventional therapies to the emergence of biologic agents. This chapter delves into the intricate mechanisms, potential applications, and future directions of biologic interventions in osteoporosis care. Biologic agents, with their targeted approach to bone health, have revolutionized the field by offering precision-driven strategies that address the underlying mechanisms of bone fragility. This chapter explores the mechanisms of action of various biologics, including Receptor Activator of Nuclear Factor Kappa-B Ligand (RANKL) inhibitors, monoclonal antibodies targeting sclerostin, parathyroid hormone (PTH) analogues, and cathepsin K inhibitors. It discusses their potential benefits, limitations, and safety considerations, while shedding light on the promise of combination therapies that merge biologic agents with traditional approaches. Furthermore, the chapter delves into the potential applications of biologic agents in specific patient populations, the role of biomarkers in predicting treatment responses, and the influence of emerging biological targets. It also explores the advancements in novel targets and drug delivery systems that aim to enhance treatment convenience and effectiveness. By tailoring treatments based on patient characteristics and exploring novel therapeutic targets, the chapter envisions a future of precision medicine in osteoporosis care. As research continues to evolve, the chapter anticipates a transformative impact on bone health outcomes, fracture prevention, and overall quality of life for individuals at risk of osteoporosis-related fractures. Through comprehensive insights into the mechanisms, applications, and future directions of biologic agents, this chapter offers a holistic perspective on the evolving landscape of osteoporosis management.

Molecular Subtype Classification of Postmenopausal Osteoporosis and Immune Infiltration Microenvironment Based on Bioinformatics Analysis of Osteoclast-Regulatory Genes

Osteoporosis is common in postmenopausal women but is often asymptomatic until a fracture occurs, highlighting the importance of early screening and preventive interventions. This study aimed to develop molecular subtype risk stratification of postmenopausal osteoporosis and analyze the immune infiltration microenvironment. Microarray data for osteoporosis were downloaded and analyzed. Logistic and least absolute shrinkage and selection operator (LASSO) regression analyses were used to construct the molecular risk model. Circulating blood samples were collected from 10 enrolled participants to validate the key differentially expressed genes, and consistent clustering based on the expression profiles of candidate genes was performed to obtain molecular subtypes. Three key genes, CTNNB1, MITF, and TNFSF11, were obtained as variables and used to construct the risk model. External experimental validation showed substantial differences in the three key genes between patients with osteoporosis and the controls (p < 0.05). Three subtypes were obtained based on dimensionality reduction clustering results. Cluster 3 had significantly more patients with low bone mineral density (BMD), whereas Cluster 2 had significantly more patients with high BMD (p < 0.05). This study introduced a novel molecular risk model and subtype classification system, which is an evidence-based screening strategy that will guide the active prevention, early diagnosis, and treatment of osteoporosis in high-risk postmenopausal women.

Curculigoside attenuates osteoporosis through regulating DNMT1 mediated osteoblast activity

This work aims to study the function of curculigoside in osteoporosis and explore whether DNMT1 is closely involved in osteoblast activity. After OB-6 osteoblasts were treated with hydrogen peroxide (H2O2), a curculigoside treatment group was set up and a series of biological tests including MTT, flow cytometry, western blotting, ROS fluorescence intensity, mitochondrial membrane potential, and ELISA experiments were performed to verify the effect of curculigoside on the activity of osteoblasts. Then, alkaline phosphatase (ALP) activity, alizarin red staining, PCR, and western blotting assays were performed to detect the effects of curculigoside on osteoblast function. By constructing DNMT1 knockdown and overexpression OB-6 cell lines, the effect of DNMT1 on osteoblast function was verified. In addition, the expression level of Nrf2 in each group was detected to speculate the mechanism of DNMT1 in osteoporosis. The cell activity and level of bcl-2 and SOD were significantly increased; the cell apoptosis, ROS fluorescence intensity, mitochondrial membrane potential, MDA and level of caspase-3, Bax, and CAT was reduced in curculigoside treatment group compared with H2O2-induced OB-6 osteoblasts. Meanwhile, the ALP activity, number and area of bone mineralized nodules, and gene and protein expression of OSX and OPG were significantly elevated in curculigoside group. Moreover, DNMT1 knockdown had a similar promotion effect on osteoblast function as curculigoside, and DNMT1 overexpression could reverse the promotion effect of curculigoside on osteoblast function. Further mechanistic studies speculated that DNMT1 might play a role in osteoporosis by affecting Nrf2 methylation. Curculigoside enhances osteoblast activity through DNMT1 controls of Nrf2 methylation.