Osteogenic effect of alogliptin in chemical-induced bone loss: a tri-modal in silico, in vitro, and in vivo analysis.

OBJECTIVE: To investigate the effects of Alogliptin in chemical-induced post-menopausal osteoporosis. METHODOLOGY: The binding affinity of alogliptin with osteogenic proteins was analysed in silico. The effect of alogliptin on osteogenic proteins and mineralization of osteoblastic cells was evaluated in UMR-106 cells. Further, in vivo anti-osteoporotic activity of alogliptin was evaluated in postmenopausal osteoporosis. Various bone turnover markers were assayed in serum. This followed the analysis of microarchitecture of bone, histology, and immunohistochemistry (IHC) of bone tissue. RESULTS: Docking scores showed that alogliptin has binding affinity for bone alkaline phosphatase (BALP), osteocalcin, and bone morphogenic protein (BMP-2). Alogliptin also enhanced mineralization of osteoblast cells, evidenced with increased ALP, osteocalcin, and BMP-2. Animal studies revealed significant elevation of bone formation markers, bone ALP, osteocalcin and BMP-2, and decreased bone resorption markers, receptor activator of NF-κß (RANKL), cathepsin K (CTSK), tartrate resistant acid phosphatase (TRAcP5b) in VCD-induced post-menopausal osteoporosis. Micro computed tomography (µCT) analysis and histology of femur bone and lumbar vertebrae demonstrated decrease in trabecular separation and improved bone density. IHC of femur showed reduced DPP4 enzyme. CONCLUSIONS: Alogliptin increased mineralization in osteoblast cells. It had beneficial effects also altered bone turnover markers, repaired the trabecular microstructure, improved bone mineral density, and exhibited bone forming capacity targeting DPP-4 enzyme in postmenopausal osteoporosis.

Integrated Single-cell RNA-seq and Bulk RNA-seq Identify Diagnostic Biomarkers for Postmenopausal Osteoporosis.

AIM: We aimed to explore diagnostic biomarkers of postmenopausal osteoporosis (PMOP). BACKGROUND: PMOP brings enormous physical and economic burden to elderly women. OBJECTIVES: This study aims to screen new biomarkers for osteoporosis, providing insights for early diagnosis and therapeutic targets of osteoporosis. METHODS: Weighted gene co-expression network analysis (WGCNA) was applied to identify osteoporosis-related hub genes. Single-cell transcriptomic atlas of osteoporosis was depicted and the heterogeneity of monocytes was analyzed, based on which the biomarkers for osteoporosis were screened. Gene set enrichment analysis (GSEA) was conducted on the biomarkers. The diagnostic model (nomogram) was established and evaluated based on the expression levels of biomarkers. Additionally, the transcription factor (TF) regulatory network was constructed to predict the potential TF and targeted miRNA of biomarkers. The drugs with significant correlation with biomarkers were identified by Spearman correlation analysis. RESULTS: We obtained 30 osteoporosis-associated hub genes. 9 cell types were identified, and the monocytes were subdivided to 4 subtypes. Three biomarkers, DHX29, LSM5, and UBE2V2, were screened. DHX29 and UBE2V2 were highly expressed in non-classical monocytes, while LSM5 exhibited the highest expression in other monocytes, followed by non-classical monocytes. GSEA indicated that osteoporosis may be correlated with vascular calcification and the biomarkers may be involved in the formation of immune cells. Then, nomogram was constructed and exhibited good robustness. In addition, MYC and SETDB1 were the shared IF in three biomarkers, which may play critical regulatory roles in the progression of osteoporosis. Moreover, 41, 49, and 68 drugs appeared significant correlations with DHX29, LSM5, and UBE2V2, respectively. CONCLUSION: This study provided a basis for early diagnosis and targeted treatment of osteoporosis.

Multi-omics and bioinformatics for the investigation of therapeutic mechanism of roucongrong pill against postmenopausal osteoporosis.

ETHNOPHARMACOLOGICAL RELEVANCE: The Roucongrong Pill (RCRP), originating from the historical General Medical Collection of Royal Benevolence, is frequently used to treat postmenopausal osteoporosis (PMOP). Despite its prevalent application, the specific anti-osteoporotic mechanisms of RCRP remain to be elucidated. AIM OF THE STUDY: This study aims to elucidate the therapeutic mechanism of RCRP in the context of ovariectomy (OVX)-induced PMOP in rats. By employing an integrative approach, the research combines medicinal chemistry, gut microbiota (GM) profiling, metabolomics, MetOrigin traceability, network pharmacology, molecular docking, and molecular dynamics simulations to deliver a comprehensive analysis. MATERIALS AND METHODS: Sprague-Dawley (SD) rats underwent bilateral OVX to establish a PMOP model. The therapeutic efficacy of RCRP was evaluated through bone metrics (BMD, bone strength, BV/TV, Tb.Sp), hematoxylin and eosin (H&E) histological assessment, and bone metabolism markers (OPG, BALP, TRACP-5b, ß-CTX, RANKL). Fecal metabolomics and 16S rDNA sequencing were employed to assess the influence of RCRP on GM and metabolite profiles. Furthermore, MetOrigin facilitated the traceability analysis of relevant metabolites. Molecular docking identified potential RCRP compounds with anti-PMOP activity, while their stability and protein interactions were assessed through molecular dynamics simulations. Network pharmacology further confirms the targets of action. RESULTS: RCRP alleviated PMOP in rats, enhancing bone strength, cortical and trabecular BMD, BV/TV, and serum OPG levels, while reducing Tb.Sp, serum BALP, TRACP-5b, ß-CTX, and RANKL concentrations. A total of twenty-six distinct metabolites were identified, of which ten-tribufos, sulfoacetic acid, betamethasone dipropionate, 9-oxooctadeca-10,12,15-trienoic acid, menatetrenone, piperlongumine, maltopentaose, enol-phenylpyruvate, catechol, pentaacetate, and (+)-2-methylpropanoic acid-exhibited correlations with six GM species: Turicibacter, Roseburia, Colidextribacter, Helicobacter, Odoribacter, and Lachnoclostridium, as determined by Spearman's correlation analysis. Notably, MetOrigin revealed the microbial metabolism of taurine and hypotaurine, along with host-specific steroid hormone synthesis. Computational docking studies demonstrated robust interactions between five RCRP-derived steroids (hydroxyecdysone, corticosterone, trilostane, 5α-androstan-3,6,17-trione, and cortisol) and key enzymes (estradiol 17α-dehydrogenase and UDP-glucuronosyltransferase), suggesting a potential enhancement of therapeutic efficacy against PMOP. Furthermore, molecular dynamics simulations indicated stable interactions between hydroxyecdysone and two proteins, with binding free energies of -67.427 kJ/mol and -156.948 kJ/mol, respectively. Through network pharmacology and molecular docking approaches, potential targets of these metabolites were identified, including estrogen receptors ESR1 and ESR2, dual specificity phosphatase 6 (DUSP6), sex hormone-binding globulin (SHBG), prostaglandin E receptor 4 (PTGER4), cannabinoid receptor 2 (CNR2), cathepsin K (CTSK), and androgen receptor (AR). CONCLUSIONS: RCRP effectively mitigates OVX-induced bone loss in PMOP rats by modulating GM and associated metabolites, along with their potential targets and key metabolic pathways, including taurine and hypotaurine metabolism, as well as steroid hormone biosynthesis. These findings offer new insights into the therapeutic mechanisms by which RCRP may alleviate PMOP.

Osteoporosis in postmenopausal women is associated with disturbances in gut microbiota and migration of peripheral immune cells.

BACKGROUND: Postmenopausal osteoporosis (PMO) results from a reduction in bone mass and microarchitectural deterioration in bone tissue due to estrogen deficiency, which may increase the incidence of fragility fractures. In recent years, the "gut-immune response-bone" axis has been proposed as a novel potential approach in the prevention and treatment of PMO. Studies on ovariectomized murine model indicated the reciprocal role of Th17 cells and Treg cells in the aetiology of osteoporosis. However, the relationship among gut microbiota, immune cells and bone metabolic indexes remains unknown in PMO. METHODS: A total of 77 postmenopausal women were recruited for the study and divided into control (n = 30), osteopenia (n = 19), and osteoporosis (n = 28) groups based on their T score. The frequency of Treg and Th17 cells in lymphocytes were analyzed by flow cytometry. The serum levels of interleukin (IL)-10, 17 A, 1ß, 6, tumor necrosis factor (TNF)-α, and lipopolysaccharide (LPS) were determined via enzyme-linked immunosorbent assay. Additionally, 16S rRNA gene V3-V4 region sequencing analysis was performed to investigate the gut microbiota of the participants. RESULTS: The results demonstrated decreased bacterial richness and diversed intestinal composition in PMO. In addition, significant differences of relative abundance of the gut microbial community in phylum and genus levels were found, mainly including increased Bacteroidota, Proteobacteria, and Campylobacterota, as well as reduced Firmicutes, Butyricicoccus, and Faecalibacterium. Intriugingly, in the osteoporosis group, the concentration of Treg cells and associated IL-10 in peripheral circulation was negatively regulated, while other chronic systemic proinflammatory cytokines and Th17 cells showed opposite trends. Moreover, significantly elevated plasma lipopolysaccharide (LPS) in patients with osteoporosis indicated that disrupted intestinal integrity and permeability. A correlation analysis showed close relationships between gut bacteria and inflammation. CONCLUSIONS: Collectively, these observations will lead to a better understanding of the relationship among bone homeostasis, the microbiota, and circulating immune cells in PMO. The elevated LPS levels of osteoporosis patients which not only indicate a breach in intestinal integrity but also suggest a novel biomarker for assessing osteoporosis risk linked to gut health.

In-silico analysis predicts disruption of normal angiogenesis as a causative factor in osteoporosis pathogenesis.

Angiogenesis-osteogenesis coupling is critical for proper functioning and maintaining the health of bones. Any disruption in this coupling, associated with aging and disease, might lead to loss of bone mass. Osteoporosis (OP) is a debilitating bone metabolic disorder that affects the microarchitecture of bones, gradually leading to fracture. Computational analysis revealed that normal angiogenesis is disrupted during the progression of OP, especially postmenopausal osteoporosis (PMOP). The genes associated with OP and PMOP were retrieved from the DisGeNET database. Hub gene analysis and molecular pathway enrichment were performed via the Cytoscape plugins STRING, MCODE, CytoHubba, ClueGO and the web-based tool Enrichr. Twenty-eight (28) hub genes were identified, eight of which were transcription factors (HIF1A, JUN, TP53, ESR1, MYC, PPARG, RUNX2 and SOX9). Analysis of SNPs associated with hub genes via the gnomAD, I-Mutant2.0, MUpro, ConSurf and COACH servers revealed the substitution F201L in IL6 as the most deleterious. The IL6 protein was modeled in the SWISS-MODEL server and the substitution was analyzed via the YASARA FoldX plugin. A positive ΔΔG (1.936) of the F201L mutant indicates that the mutated structure is less stable than the wild-type structure is. Thirteen hub genes, including IL6 and the enriched molecular pathways were found to be profoundly involved in angiogenesis/endothelial function and immune signaling. Mechanical loading of bones through weight-bearing exercises can activate osteoblasts via mechanotransduction leading to increased bone formation. The present study suggests proper mechanical loading of bone as a preventive strategy for PMOP, by which angiogenesis and the immune status of the bone can be maintained. This in silico analysis could be used to understand the molecular etiology of OP and to develop novel therapeutic approaches.

Estrogen deficiency-mediated osteoimmunity in postmenopausal osteoporosis.

Postmenopausal osteoporosis (PMO) is a common disease associated with aging, and estrogen deficiency is considered to be the main cause of PMO. Recently, however, osteoimmunology has been revealed to be closely related to PMO. On the one hand, estrogen deficiency directly affects the activity of bone cells (osteoblasts, osteoclasts, osteocytes). On the other hand, estrogen deficiency-mediated osteoimmunity also plays a crucial role in bone loss in PMO. In this review, we systematically describe the progress of the mechanisms of bone loss in PMO, estrogen deficiency-mediated osteoimmunity, the differences between PMO patients and postmenopausal populations without osteoporosis, and estrogen deficiency-mediated immune cells (T cells, B cells, macrophages, neutrophils, dendritic cells, and mast cells) activity. The comprehensive summary of this paper provides a clear knowledge context for future research on the mechanism of PMO bone loss.

Similarities and differences between European guidelines for the management of postmenopausal osteoporosis.

We conducted a review of 10 national guidelines from five EU countries to identify similarities or differences in recommendations for the management of patients with osteoporosis. We found general alignment of key recommendations; however, there are notable differences, largely attributed to country-specific approaches to risk assessment and reimbursement conditions. INTRODUCTION: The classification of fracture risk is critical for informing treatment decisions for post-menopausal osteoporosis. The aim of this review was to summarise 10 national guidelines from five European countries, with a focus on identifying similarities or differences in recommendations for the management of patients with osteoporosis. METHODS: We summarised the European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Disease-International Osteoporosis Foundation guidelines and reviewed guidelines from France, Germany, Italy, Spain and the UK. RESULTS: The approach to risk assessment differed across the guidelines. In France, and Spain, risk assessment was based on DXA scans and presence of prior fractures, whereas UK, German and Italian guidelines recommended use of a validated risk tool. These differences led to distinct definitions of very high and high-risk patients. Guidelines aligned in recommending antiresorptive and anabolic agents as pharmacologic options for the management of osteoporosis, with sequential treatment recommended. There was agreement that patients at high or very high risk of fracture or with severe osteoporosis should receive anabolic agents first, followed by antiresorptive drugs. Variations were identified in recommendations for follow up of patients on anti-osteoporosis therapies. Reimbursement conditions in each country were a key difference identified. CONCLUSIONS: Criteria for risk assessment of fractures differ across European guidelines which may impact treatment and access to anabolic agents. Harmonisation across EU guidelines may help identify patients eligible for treatment and impact treatment uptake. However, country-specific reimbursement and prescribing processes may present a challenge to achieving a consistent approach across Europe.

Efficacy and safety of denosumab and teriparatide versus oral bisphosphonates to treat postmenopausal osteoporosis: a systematic review and meta-analysis.

Study Design: A systematic review and Meta-analysis. Objective: To compare the efficacy and safety of denosumab and teriparatide versus oral bisphosphonates to treat postmenopausal osteoporosis. Summary of Background Data: While bisphosphonates have historically been the cornerstone of pharmacological management for bone protection in patients, emerging evidence suggests that teriparatide and denosumab warrant further investigation as potential first-line treatments. The optimal choice among denosumab, teriparatide, and oral bisphosphonates for the treatment of postmenopausal osteoporosis remains a subject of ongoing debate and controversy within the scientific community. Methods: This systematic review adhered meticulously to the rigorous standards outlined by the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines as well as the Cochrane Collaboration recommendations. Additionally, it employed the AMSTAR (Assessing the methodological quality of systematic reviews) criteria to ensure methodological robustness and enhance the credibility of the findings. A systematic electronic search was conducted across Web of Science, PubMed, and the Cochrane Library databases from their inception dates up to February 2024. Results: In this meta-analysis of studies, our findings suggest that compared to bisphosphonates, both teriparatide and denosumab demonstrated notable increases in percentage changes in lumbar spine bone mineral density (BMD) among postmenopausal osteoporosis patients. Furthermore, denosumab exhibited superiority over teriparatide and oral bisphosphonates in enhancing percentage changes in both femoral neck and total hip BMD, indicating its potential as a more efficacious option. Regarding safety outcomes, no significant differences were observed in the incidence of serious adverse events among patients treated with teriparatide, denosumab, and bisphosphonates. However, teriparatide showed superiority over oral bisphosphonates in terms of a lower risk of general adverse events, suggesting a favorable safety profile. Conclusion: In conclusion, our study suggests that teriparatide and denosumab demonstrate comparable or potentially superior efficacy and safety profiles compared to oral bisphosphonates for the treatment of postmenopausal osteoporosis. Systematic Review Registration: PROSPERO, identifier CRD42024508382.

Integrated single-cell and bulk RNA sequencing analysis reveal immune-related biomarkers in postmenopausal osteoporosis.

Background: Postmenopausal osteoporosis (PMOP) represents as a significant health concern, particularly as the population ages. Currently, there is a paucity of comprehensive descriptions regarding the immunoregulatory mechanisms and early diagnostic biomarkers associated with PMOP. This study aims to examine immune-related differentially expressed genes (IR-DEGs) in the peripheral blood mononuclear cells of PMOP patients to identify immunological patterns and diagnostic biomarkers. Methods: The GSE56815 dataset from the Gene Expression Omnibus (GEO) database was used as the training group, while the GSE2208 dataset served as the validation group. Initially, differential expression analysis was conducted after data integration to identify IR-DEGs in the peripheral blood mononuclear cells of PMOP. Subsequently, feature selection of these IR-DEGs was performed using RF, SVM-RFE, and LASSO regression models. Additionally, the expression of IR-DEGs in distinct bone marrow cell subtypes was analyzed using single-cell RNA sequencing (scRNA-seq) datasets, allowing the identification of cellular communication patterns within various cell subgroups. Finally, molecular subtypes and diagnostic models for PMOP were constructed based on these selected IR-DEGs. Furthermore, the expression levels of characteristic IR-DEGs were examined in rat osteoporosis (OP) models. Results: Using machine learning, six IR-DEGs (JUN, HMOX1, CYSLTR2, TNFSF8, IL1R2, and SSTR5) were identified. Subsequently, two molecular subtypes of PMOP (subtype 1 and subtype 2) were established, with subtype 1 exhibiting a higher proportion of M1 macrophage infiltration. Analysis of the scRNA-seq dataset revealed 11 distinct cell clusters. It was noted that JUN was significantly overexpressed in M1 macrophages, while HMOX1 showed a marked elevation in endothelial cells and M2 macrophages. Cell communication results suggested that the PMOP microenvironment features increased interactions among M2 macrophages, CD8+ T cells, Tregs, and fibroblasts. The diagnostic model based on these six IR-DEGs demonstrated excellent diagnostic performance (AUC = 0.927). In the OP rat model, the expression of IL1R2 and TNFSF8 were significantly elevated. Conclusion: JUN, HMOX1, CYSLTR2, TNFSF8, IL1R2, and SSTR5 may serve as promising molecular targets for diagnosing and subtyping patients with PMOP. These results offer novel perspectives on the early diagnosis of PMOP and the advancement of personalized immune-based therapies.

Olink Proteomics for the Identification of Biomarkers for Early Diagnosis of Postmenopausal Osteoporosis.

This investigation aims to employ Olink proteomics in analyzing the distinct serum proteins associated with postmenopausal osteoporosis (PMOP) and identifying prognostic markers for early detection of PMOP via molecular mechanism research on postmenopausal osteoporosis. Postmenopausal women admitted to Beijing Jishuitan Hospital were randomly selected and categorized into three groups based on their dual-energy X-ray absorptiometry (DXA) T-scores: osteoporosis group (n = 24), osteopenia group (n = 20), and normal bone mass group (n = 16). Serum samples from all participants were collected for clinical and bone metabolism marker measurements. Olink proteomics was utilized to identify differentially expressed proteins (DEPs) that are highly associated with postmenopausal osteoporosis. The functional analysis of DEPs was performed using Gene Ontology and Kyto Encyclopedia Genes and Genomes (KEGG). The biological characteristics of these proteins and their correlation with PMOP were subsequently analyzed. ROC curve analysis was performed to identify potential biomarkers with the highest diagnostic accuracy for early stage PMOP. Through Olink proteomics, we identified five DEPs highly associated with PMOP, including two upregulated and three downregulated proteins. TWEAK and CDCP1 markers exhibited the highest area under the curve (0.8188 and 0.8031, respectively). TWEAK and CDCP1 have the potential to serve as biomarkers for early prediction of postmenopausal osteoporosis.

Teriparatide in postmenopausal osteoporosis: uncovering novel insights into efficacy and safety compared to other treatments - a systematic review and meta-analysis.

Objective: The aim of the study was to evaluate the efficacy and safety of teriparatide compared to other treatments for postmenopausal osteoporosis. Methods: A review of studies from 2000 to January 2023 analyzed randomized controlled trials on postmenopausal women treated with teriparatide (PTH 1-34), comparing it to placebo or other osteoporosis treatments. The analysis focused on bone mineral density (BMD), bone turnover markers, and clinical outcomes, employing Review Manager 5.4.1 and the RoB 2 tool for bias assessment. Results: Our analysis of 23 randomized controlled trials (RCTs) found that PTH (134) treatment significantly increased lumbar spine BMD (mean difference (MD) = 0.02, 95% CI: 0.01-0.03) and femoral neck BMD (MD = 0.01, 95% CI: 0.00-0.01). However, there were no significant changes in total hip and radial bone BMD among the 3536 and 2046 participants, respectively. We also found that PTH (1-34) increased P1NP in a larger cohort (n = 1415) when compared to osteocalcin (n = 206). Although the risk of adverse events increased (relative risk (RR) = 1.65, 95% CI: 1.32-2.07), the incidence of fractures decreased significantly (RR = 0.57, 95% CI: 0.45-0.072), with no significant difference observed in mortality rates between treatment and control groups. Conclusion: Teriparatide improves lumbar spine and femoral neck BMD in postmenopausal women. Particularly notable is the novel finding regarding its effect on radius BMD, an area less explored in previous research. Despite an uptick in adverse events, the marked decrease in fracture incidence confirms its clinical utility for high-risk osteoporosis patients, highlighting the necessity for ongoing investigations into its full skeletal effects.

The influence of modified Qing E Formula on the differential expression of serum exosomal miRNAs in postmenopausal osteoporosis patients.

Objective: Although guidelines support the efficacy of Modified Qing' E Formula (MQEF) in treating postmenopausal osteoporosis (PMOP), its underlying mechanisms remain incompletely understood. This retrospective investigation aims to elucidate MQEF's impact on serum exosomal miRNA expression in postmenopausal osteoporosis patients and to explore potential therapeutic mechanisms. Methods: Following ethical approval and registration, postmenopausal osteoporosis patients aged 50-85 years, meeting the diagnostic criteria were randomly selected and received MQEF decoction supplementary therapy. Serum samples were collected pre- and post-treatment, followed by isolation and sequencing of exosomal miRNAs. Differential miRNAs in serum exosomes were identified, and bioinformatics analysis was conducted to discern the principal exosomal miRNAs involved in MQEF's effects on PMOP and the associated signaling pathways. Results: Eighteen clinical blood samples were collected. A total of 282,185 target genes were detected across the three groups. 306 miRNAs exhibited altered expression in serum exosomes of PMOP patients, while MQEF intervention resulted in changes in 328 miRNAs. GO enrichment analysis revealed the immune and endocrine systems was pertained. KEGG enrichment analysis indicated associations between PMOP occurrence and MQEF treatment with cytokine interactions, oxidative phosphorylation, and the renin-angiotensin system. Intersectional analysis identified 17 miRNAs, including 2 consistent trends. miR-3188 as a potentially pivotal miRNA implicated in both PMOP occurrence and MQEF treatment. Conclusion: This study constitutes the first randomized, retrospective clinical exploration confirming that MQEF demonstrates regulatory influence over exosomal miRNA expression in PMOP patients' serum, its impact likely involves modulation of the immune and endocrine systems, as well as the renin-angiotensin system.

Arctigenin Modulates Adipogenic-Osteogenic Balance in the Bone Marrow Microenvironment of Ovariectomized Rats via the MEK1/PPARγ/Wnt/ß-Catenin Pathway.

Arctigenin (Ar) is a promising therapeutic candidate for postmenopausal osteoporosis (PMOP). This study explores its mechanism by examining its effects on adipogenesis and osteogenesis in ovariectomized (OVX) rats. In vitro, Ar effectively suppressed the adipogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) from OVX rats, reducing lipid droplet formation and downregulating proteins associated with lipid synthesis. In vivo, Ar treatment significantly reduced bone loss, inhibited adipocyte development, improved lipid metabolism, and promoted bone formation in OVX rats. Mechanistically, Ar inhibited the phosphorylation of Mitogen-Activated Protein Kinase 1 (MEK1), downregulated Peroxisome Proliferator-Activated Receptor gamma (PPARγ), promoted the accumulation of ß-catenin in the nucleus, and prevented the direct binding of PPARγ to ß-catenin in BMSCs. This regulation of the PPARγ/Wnt signaling axis underlies its dual role in inhibiting adipogenesis and promoting osteogenesis. Notably, co-treatment with rosiglitazone (RGZ) reversed the effects of Ar on adipogenesis and osteogenesis without affecting MEK1 inhibition. These findings offer valuable insights into arctigenin's potential as a therapeutic strategy for PMOP by modulating MEK1 signaling and regulating the PPARγ/Wnt axis.

Investigating the protective effect of loganin in ovariectomy­induced bone loss through network pharmacology and molecular docking.

Loganin, a major iridoid glycoside derived from Cornus officinalis, exerts strong anti-inflammatory property. The present study aimed to investigate the underlying mechanism of loganin to reduce estrogen deficiency-induced bone loss through a combination of network pharmacology, molecular docking and in vivo validation. First, the drug targets and structural interactions of loganin with osteoclasts on postmenopausal osteoporosis (PMOP) were predicted through network pharmacology and molecular docking. An ovariectomized (OVX) mouse model was established to experimentally validate loganin's anti-PMOP efficacy, supported by its protective effect on bone destruction and excessive inflammatory cytokines. The top 10 core targets of loganin generated by a protein-protein interaction network were the following: GAPDH, VEGFA, EGFR, ESR1, HRAS, SRC, FGF2, HSP90AA1, PTGS2 and IL-2. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses indicated that loganin suppressed PMOP via mediating inflammation, bone formation, IL-17 signaling pathway and NF-κB signaling pathway. Molecular docking results indicated strong binding between loganin and core targets, in which the binding energy was approximately -5.2 and -7.4 kcal/mol. In vivo mouse model revealed that loganin inhibited the expression of pro-osteoclastic markers, such as tartrate-resistant acid phosphatase, C-terminal telopeptide, TNF-α and IL-6, enhanced the secretion of bone formation markers, such as procollagen type I intact n-terminal pro-peptide and IL-10, and improved bone micro-structure (bone volume/tissue volume and trabecular number), representative of the anti-resorptive effect mediated by loganin. In summary, the present study combined network pharmacology and molecular docking to predict the underlying mechanism of loganin against PMOP, validated by the in vivo mouse model showing that loganin attenuated OVX-induced bone loss by inhibiting inflammation.

Efficacy and safety of odanacatib in the treatment of postmenopausal women with osteoporosis: a meta-analysis.

BACKGROUND: Osteoporosis, a systemic skeletal disease, seriously affects the quality of life in postmenopausal women. As one type of cathepsin K (CatK) inhibitor, odanacatib (ODN) is a fresh medication for osteoporosis. Considering the potential of ODN, we further examined the effect and safety of ODN for postmenopausal osteoporosis (PMOP) with a meta-analysis. METHODS: PubMed, EMBASE, Cochrane Library, and Web of Science were searched for eligible studies from inception to December 29th, 2023. After that, we conducted a comprehensive meta-analysis following PRISMA guidelines. Risk of bias was meticulously investigated with the Cochrane Collaboration's tool. Efficacy was assessed with bone mineral density (BMD) at different sites (lumbar spine, trochanter, radius, femoral neck) and biomarkers of bone turnover (P1NP, uNTx/Cr, s-CTx, BSAP). Safety was evaluated by analyzing total, serious, other, and skin adverse events (AEs). RESULTS: Four random clinical trials (RCTs) were involved in our research. All trials were rated as having high quality and met the eligibility criteria. In the current research, ODN was found to elevate BMD at lumbar spine, femoral neck, total hip, trochanter and forearm, while it decreased the levels of serum C-telopeptides of type I collagen (s-CTx) as well as urinary N-telopeptide/creatinine ratio (uNTx/Cr). No significant differences were observed in AEs between the ODN group and the control group. CONCLUSIONS: ODN is a promising alternative for the treatment of PMOP on account of its excellent efficacy and credible safety. Unclear links between ODN and cardiovascular AEs require further research to clarify.

Bu-Sui-Dan Enhances Osteoblast Differentiation by Upregulating VGLL4 to Counteract TEAD4-Mediated RUNX2 Transcription Suppression in Ovariectomized Rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Postmenopausal osteoporosis (PMOP) has been considered as a major causative factor for bone-joint pain and inducing pathologic fractures. Bu-Sui-Dan (BSD), a classic ancient herbal formula, has been shown to exhibit osteoprotective effects by promoting bone marrow development and bone growth. However, the exact mechanism of BSD are still unexplored. AIM OF STUDY: The study aimed to investigate the protective effect of BSD against osteoporotic injury, and to explore whether BSD regulated BMSCs' osteogenic differentiation by targeting VGLL4, which in turn improved PMOP. MATERIALS AND METHODS: The anti-osteoporotic effect of BSD was studied in ovariectomized (OVX) rats and bone marrow mesenchymal stem cells (BMSCs). Micro-CT imaging and HE staining were performed, and the levels of osteogenic protein RUNX2 and osteogenesis-related factor VGLL4 were determined. Co-immunoprecipitation (Co-IP) was further employed to delve into the effects of BSD on the interactions between TEAD4 and RUNX2. The key osteogenic factors 1ALP, COLl1A1, and Osterix expression were detected by RT-qPCR. Co-IP and proximity ligation assay (PLA) were employed to scrutinize the influence of BSD on TEAD4 and RUNX2 inter-binding. Moreover, VGLL4 knockdown in BMSCs was conducted to confirm the role of VGLL4 in the therapeutic mechanism of BSD. RESULTS: BSD showed a dose-dependent protective effect against osteoporotic injury, as evidenced by improvement in bone volume, bone microarchitecture, and histomorphometry. Additionally, BSD treatment increased the levels of RUNX2 and its downstream target genes including ALP, COL1A1, and Osterix. Moreover, BSD upregulated VGLL4 expression and lessened TEAD4-RUNX2 interactions. In BMSCs experiment, BSD-containing serum could promote osteogenic differentiation of BMSCs, boosted the expression of osteogenesis-related factors and VGLL4 level. The knockdown of VGLL4 in BMSCs diminished the promotion effect of BSD in osteoblast differentiation, suggesting that VGLL4 play a vital role in the therapeutic effects exerted by BSD. CONCLUSION: BSD ameliorated osteoporosis injury and promoted osteoblast differentiation through upregulation of VGLL4 levels, which in turn antagonized TEAD4-mediated RUNX2 transcriptional repression. Our study implied that BSD may be an osteoporosis therapeutic agent.

miR-18a-5p promotes osteogenic differentiation of BMSC by inhibiting Notch2.

Postmenopausal osteoporosis (PMOP) is a metabolic disorder characterized by the loss of bone density, which increases the risk of developing complications such as fractures. A pivotal factor contributing to the onset of PMOP is the diminished osteogenic differentiation capacity of bone marrow mesenchymal stem cells (BMSCs). MicroRNAs (miRNAs) play a substantial role in this process; however, their specific impact on regulating BMSCs osteogenesis remains unclear. Studies have evidenced a reduced expression of miR-18a-5p in PMOP, and concomitantly, our observations indicate an augmented expression of miR-18a-5p during the osteogenic differentiation of BMSCs. This investigation seeks to elucidate the regulatory influence of miR-18a-5p on BMSC osteogenic differentiation and the underlying mechanisms. In vitro experiments demonstrated that the overexpression of miR-18a-5p facilitated the osteogenic differentiation of BMSCs, while the downregulation of miR-18a-5p yielded converse outcomes. Mechanistically, We employed bioinformatics techniques to screen out the target gene Notch2 of miR-18a-5p. Subsequently, dual-luciferase reporter gene assays and rescue experiments substantiated that miR-18a-5p promotes BMSC osteogenic differentiation by suppressing Notch2. Finally, miR-18a-5p was overexpressed via adenovirus injection into the femoral bone marrow cavity, with results demonstrating its capability to enhance osteogenic differentiation and alleviate PMOP symptoms. Our findings disclose that miR-18a-5p fosters osteogenic differentiation of BMSC by inhibiting Notch2, thereby offering novel targets and strategies for PMOP treatment.

Diversity of the diet is correlated with osteoporosis in post-menopausal women: an Iranian case-control study.

Background: Proper nutrition is a crucial factor in preventing osteoporosis, a significant pathological cause linked to skeletal weakness; this study investigated the relationship between dietary diversity score and food group diversity score with osteoporosis in postmenopausal women. Methods: This case-control study was conducted on 378 menopausal women aged 45-85 in Tehran, Iran. The age-matching method to control the confounding effect of age was used. The method of dual-energy X-ray absorptiometry (DXA) was used for assessing the bone mineral density of lumbar vertebrae and femoral neck. The bone mass status was evaluated with WHO criteria. All subjects were divided into the osteoporosis group and the non-osteoporosis group according to their T-score. A convenience sampling method was utilized to select the participants, which included two groups: case (n = 189) and control (n = 189). Data was collected using demographic and anthropometric information questionnaires, a valid 147 item food frequency questionnaire, and a physical activity questionnaire. Statistical analyses were conducted using SPSS-26, and p-values less than 0.05 were deemed to be statistically significant. Results: The results indicated significant differences in weight, body mass index, physical activity, smoking, and alcohol use between the two groups. The mean ± standard deviation of dietary diversity score (DDS) was lower in participants with osteoporosis (case) (3.31 ± 1.26) than in control (4.64 ± 1.33) (p < 0.001). The mean ± standard deviation of diversity score of cereals, fruits, and vegetables in the osteoporosis group (respectively: 0.71 ± 0.21, 0.94 ± 0.76, and 0.45 ± 0.44) was less than the control group (respectively: 0.80 ± 0.21, 1.64 ± 0.55 and 0.87 ± 0.42) (p < 0.001). After adjusting the confounding variables, the risk of osteoporosis had an inverse relationship with the diversity score of vegetable (OR = 0.16; 95%CI: 0.07-0.35), bread and cereal (OR = 0.21; 95% CI: 0.05-0.87) and fruit (OR = 0.35; 95%CI: 0.22-0.56) (p < 0.05). Nevertheless, no discernible correlation was seen between the tertiles of DDS, dairy and meat diversity score, and osteoporosis. Conclusion: We found a correlation between the diversity score of fruits, vegetables, and grains and osteoporosis. However, there is no significant correlation between the DDS triads and the diversity score of dairy products and meats with osteoporosis.

IL-16 Mediates the Effect of Circulating Metabolites on Postmenopausal Osteoporosis: A Two-Step, Multivariable Mendelian Randomization Study.

Objectives: This study aimed to explore the relationship between circulating metabolites and postmenopausal osteoporosis (PMOP) and to assess the mediating role of inflammatory factors. Methods: Utilizing summary-level data from genome-wide association studies (GWAS) and employing a Mendelian Randomization approach, a two-sample MR analysis was conducted to assess the relationship between circulating metabolites and PMOP. Additionally, a two-step MR was used to quantify the mediating impact of inflammatory factors on the effect of circulating metabolites on PMOP. Results: The results revealed a significant association between certain metabolites and the risk of PMOP, notably the ratio of free cholesterol to total lipids in very large VLDL particles (OR: 1.399, 95% CI: 1.002-1.954, p = 0.048) and IL-16 (OR: 0.773, 95% CI: 0.608-0.983, p = 0.036). IL-16 was found to partially mediate the impact of circulating metabolites on PMOP, with a mediation effect of 10.4%. Conclusion: This study underscores the crucial role of circulating metabolites and inflammatory factors in PMOP pathogenesis. A causal relationship between circulating metabolites and PMOP was established, with IL-16 mediating some effects. These findings hold promise for clinical applications in early detection, personalized medicine, and the identification of therapeutic targets for PMOP.

Morinda Officinalis Polysaccharides Inhibit Osteoclast Differentiation by Regulating miR-214-3p/NEDD4L in Postmenopausal Osteoporosis Mice.

To investigate the potential mechanism of Morinda officinalis F. C. How polysaccharides (MOPs) in regulating osteoclast differentiation and apoptosis through miR-214-3p and its target protein. Ovariectomy was performed in 8-week female C57BL6 mice to establish the postmenopausal osteoporosis (PMOP) model. Mice were treated immediately with 500 mg/kg of MOPs (prevention group); others were treated 2 weeks after operation (treatment group). Left femur bone mineral density (BMD) was examined. RAW264.7 cells were administered with receptor activator of NF-κB ligand (RANKL) to establish the osteoclast (OC) model and treated with serum containing 1 or 2 g/kg of MOPs. Apoptosis-related indexes, miR-214-3p, and Expressed Developmentally Down-regulated 4-Like (NEDD4L) were detected by western blot, quantitative real-time-reverse transcription polymerase chain reaction (qRT-PCR), and flow cytometry. OC received a miR-214-3p inhibitor or NEDD4L small interfering RNA (siRNA). MOPs reversed the PMOP-induced changes in bones. Compared with the RANKL group, MOPs increased the apoptosis and related markers in OCs. MOPs decreased the femur miR-214-3p of PMOP mice (P < 0.001). Higher concentrations of MOPs reversed the upregulation of miR-214 mRNA in OCs (P < 0.001). miR-214-3p inhibitor increased the expression of Bax and CC3 (P < 0.01) and decreased the expression of Bcl-2 (P < 0.05). NEDD4L is targeted by miR-214. NEDD4L was upregulated in the RANKL + MOPs group (P < 0.01). miR-214-3p inhibitor increased the upregulation of NEDD4L induced by MOPs (P < 0.05). siRNA NEDD4L significantly reversed the inhibition of MOPs on osteoclast differentiation with miR-214-3p inhibitor (P < 0.01). MOPs effectively prevent PMOP by inhibiting osteoclastogenesis and inducing OC apoptosis through the miR-214-3p/NEDD4L pathway.