On Osteoporosis Research Articles

Fibroblast growth factor 23-mediated regulation of osteoporosis: Assessed via Mendelian randomization and invitro study.

Despite numerous investigations on the influence of fibroblast growth factor 23 (FGF23), α-Klotho and FGF receptor-1 (FGFR1) on osteoporosis (OP), there is no clear consensus. Mendelian randomization (MR) analysis was conducted on genome-wide association studies (GWASs)-based datasets to evaluate the causal relationship between FGF23, α-Klotho, FGFR1 and OP. The primary endpoint was the odds ratio (OR) of the inverse-variance weighted (IVW) approach. Furthermore, we stably transfected FGF23-mimic or siRNA-FGF23 into human bone marrow mesenchymal stem cells (hBMSCs) in culture and determined its cell proliferation and the effects on osteogenic differentiation. Using MR analysis, we demonstrated a strong correlation between serum FGF23 levels and Heel- and femoral neck-BMDs, with subsequent ORs of 0.919 (95% CI: 0.860-0.983, p = 0.014) and 0.751 (95% CI: 0.587-0.962; p = 0.023), respectively. The expression levels of FGF23 were significantly increased in femoral neck of patients with OP than in the control cohort (p < 0.0001). Based on our invitro investigation, after overexpression of FGF23, compared to the control group, the BMSC's proliferation ability decreased, the expression level of key osteogenic differentiation genes (RUNX2, OCN and OSX) significantly reduced, mineralized nodules and ALP activity significantly decreased. After silencing FGF23, it showed a completely opposite trend. Augmented FGF23 levels are causally associated with increased risk of OP. Similarly, FGF23 overexpression strongly inhibits the osteogenic differentiation of hBMSCs, thereby potentially aggravating the pathological process of OP.

Epimedii Folium decoction ameliorates osteoporosis in mice through NLRP3/caspase-1/IL-1β signalling pathway and gut-bone axis

Aim of the studyThis study aimed to determine the effect of Epimedium brevicornu Maxim. (EF) on osteoporosis (OP) and its underlying molecular mechanisms, and to explore the existence of the “Gut-Bone Axis”. Material and methodsThe impact of EF decoction (EFD) on OP was evaluated using istopathological examination and biochemical assays. Targeted metabolomics was employed to identify key molecules and explore their molecular mechanisms. Alterations in the gut microbiota (GM) were evaluated by 16S rRNA gene sequencing. The role of the GM was clarified using an antibiotic cocktail and faecal microbiota transplantation. ResultsEFD significantly increased the weight (14.06%), femur length (4.34%), abdominal fat weight (61.14%), uterine weight (69.86%), and insulin-like growth factor 1 (IGF-1) levels (59.48%), while reducing serum type I collagen cross-linked carboxy-terminal peptide (CTX-I) levels (15.02%) in osteoporotic mice. The mechanism of action may involve the regulation of the NLRP3/cleaved caspase-1/IL-1β signalling pathway in improving intestinal tight junction proteins and bone metabolism. Additionally, EFD modulated the abundance of related GM communities, such as Lactobacillus, Coriobacteriaceae, bacteria of family S24-7, Clostridiales, and Prevotella, and increased propionate and butyrate levels. Antibiotic-induced dysbiosis of gut bacteria disrupted OP regulation of bone metabolism, which was restored by the recovery of GM. ConclusionsOur study is the first to demonstrate that EFD works in an OP mouse model by utilising GM and butyric acid. Thus, EF shows promise as a potential remedy for OP in the future.

The impact of a Fracture Liaison Service after 3years on secondary fracture prevention and mortality in a Portuguese tertiary center.

Fracture Liaison Services (FLS) have been established worldwide, with positive effects on treatment, secondary fracture, mortality, and economic burden. However, no study has evaluated their impact on the Portuguese population. Therefore, we purposed to evaluate the effect of an FLS model in a Portuguese center on osteoporosis (OP) treatment, secondary fracture, and mortality rates, 3years after a fragility fracture. Patients over 50years old, admitted with a fragility fracture, between January 2017 and December 2020, were included in this retrospective study. Patients evaluated after FLS implementation (2019-2020) were compared with those evaluated before (2017-2018) and followed for 36months. Predictors of secondary fracture and mortality were assessed using a multivariate Cox regression model, adjusted to potential confounders. A total of 551 patients were included (346 before and 205 after FLS). The FLS significantly increased the rate of OP treatment, when compared with standard clinical practice (8.1% vs 77.6%). During follow-up, the secondary fracture rate was 14.7% and 7.3%, before and after FLS, respectively. FLS was associated with a lower risk of secondary fracture (HR 0.39, C.I. 0.16-0.92). Although we observed a lower mortality rate (25.1% vs 13.7%), FLS was not a significant predictor of survival. Implementing the FLS model in a Portuguese center has increased OP treatment and reduced the risk of secondary fracture. We believe that our work supports adopting FLS models in national programs.

Total Flavonoids from Rhizoma Drynariae (Gusuibu) Alleviates Diabetic Osteoporosis by Activating BMP2/Smad Signaling Pathway.

Diabetic osteoporosis (DOP) is a widespread public health problem. The flavonoids of Rhizoma Drynariae (RDF) have a clear preventive and therapeutic effect on osteoporosis (OP), but it is not yet clear whether RDF has an anti-DOP and whether its mechanism is related to the activation of the BMP2/Smad signaling pathway. The current study aimed to study this effect of RDF in DOP rats and the possible involvement of the BMP2/Smad signaling pathway activation. Following intragastric administration of RDF for 12 weeks, the body weight, blood glucose, and the bone histopathological changes detected by hematoxylin-eosin (H&E) and calcein staining were monitored, while bone parameters were regularly assessed from observations made by micro-CT. At the end of the experiment, the expression of Bmp2, Bmpr1a, Runx2, and Smad4/5 genes was detected by real-time PCR (RT-PCR). Meanwhile, western blotting or immunohistochemical staining monitored the protein expressions of BMP2, RUNX2, and SMAD5 in the bone. The results firstly indicated that RDF significantly alleviated the signs and symptoms of DOP, which manifested as improved body weight and blood glucose. As obtained from the results of histopathology and micro-CT, RDF could promote the formation of bone trabeculae and alter several the bone microstructure parameters, including an increase in the bone volume/total volume (BV/TV), connective density (Conn-Dens), and trabecular bone number (Tb.N), as well as a decrease in the trabecular spacing (Tb.Sp). The western blotting analysis and RT-PCR results also confirmed that RDF could markedly increase the mRNA expression levels of Bmp2, Bmpr1α, Smad4, Runx2, and Smad5 in the bone, as well as the corresponding protein expression levels of BMP2, RUNX2, and SMAD5. These results reveal that RDF can activate the BMP2/Smad signaling pathway, thus promoting bone remodeling in DOP rats. RDF can increase bone trabeculae and bone mineral density by promoting bone formation and inhibiting bone absorption, thereby playing a role in improving DOP. This effect is related to the regulation of the BMP2/Smad signaling pathway.

Smoking index and COPD duration as potential risk factors for development of osteoporosis in patients with non-small cell lung cancer – A retrospective case control study evaluated by CT Hounsfield unit

ObjectiveTo investigate the effect of smoking index (calculated as number of cigarettes per day × smoking years) and chronic obstructive pulmonary disease (COPD) duration on osteoporosis (OP)evaluated by opportunistic chest CT in patients with non-small cell lung cancer (NSCLC). MethodsA total of 101 patients diagnosed with NSCLC were included in our cohort study. Among them, 50 patients with a history of smoking and COPD were assigned to the experimental group, while 51 patients without a history of smoking and COPD were assigned to the control group. Hounsfield unit (HU) value was measured by conventional chest CT to investigate the bone mineral density; and the mean values of axial HU value in the upper, middle and lower parts of T4, T7, T10 and L1 vertebral bodies were measured as the study variables. ResultsThere were no significant differences in gender, age, body mass index, type of lung cancer, clinical stage of lung cancer and comorbidities between the two groups (P = 0.938，P = 0.158，P = 0.722,P = 0.596,P = 0.813,P = 0.655). The overall mean HU values of T4, T7, T10, L1 in the experimental group were 116.60 ± 30.67, 110.56 ± 30.03, 109.18 (96.85–122.95), 94.63 (85.20–104.12) and 106.86 ± 22.26, respectively, which were significantly lower than those in the control group (189.55 ± 34.57, 174.54 ± 35.30, 172.73 (156.33–199.50), 158.20 (141.60–179.40) and 177.50 ± 33.49) (P ＜0.05). And in the experimental group, smoking index and COPD duration were significantly and negatively correlated with HU values (r = −0.627, −0.542, P ＜0.05, respectively). ConclusionPatients with NSCLC who have a history of smoking and COPD exhibit a notably lower HU value compared to the control groups. Additionally, it has been observed that the smoking index and duration of COPD may be influential factors affecting bone mineral density in NSCLC patients.

Wen-Shen-Tong-Luo-Zhi-Tong Decoction regulates bone–fat balance in osteoporosis by adipocyte-derived exosomes

Context Wen-Shen-Tong-Luo-Zhi-Tong (WSTLZT) Decoction is a Chinese prescription with antiosteoporosis effects, especially in patients with abnormal lipid metabolism. Objective To explore the effect and mechanism of WSTLZT on osteoporosis (OP) through adipocyte-derived exosomes. Materials and methods Adipocyte-derived exosomes with or without WSTLZT treated were identified by transmission electron microscopy, nanoparticle tracking analysis (NTA) and western blotting (WB). Co-culture experiments for bone marrow mesenchymal stem cells (BMSCs) and exosomes were performed to examine the uptake and effect of exosome in osteogenesis and adipogenic differentiation of BMSC. MicroRNA profiles, luciferase and IP were used for exploring specific mechanisms of exosome on BMSC. In vivo, 80 Balb/c mice were randomly divided into four groups: Sham, Ovx, Exo (30 μg exosomes), Exo-WSTLZT (30 μg WSTLZT-exosomes), tail vein injection every week. After 12 weeks, the bone microstructure and marrow fat distribution were analysed by micro-CT. Results ALP, Alizarin red and Oil red staining showed that WSTLZT-induced exosomes from adipocyte can regulate osteoblastic and adipogenic differentiation of BMSC. MicroRNA profiles observed that WSTLZT treatment resulted in 87 differentially expressed miRNAs (p < 0.05). MiR-122-5p with the greatest difference was screened by q-PCR (p < 0.01). The target relationship between miR-122-5p and SPRY2 was tested by luciferase and IP. MiR-122-5p negatively regulated SPRY2 and elevated the activity of MAPK signalling pathway, thereby regulating the osteoblastic and adipogenic differentiation of BMSC. In vivo, exosomes can not only improve bone microarchitecture but also significantly reduce accumulation of bone marrow adipose. Conclusions WSTLZT can exert anti-OP effect through SPRY2 via the MAKP signalling by miR-122-5p carried by adipocyte-derived exosomes.

Peiminine regulates bone-fat balance by canonical Wnt/β-catenin pathway in an ovariectomized rat model.

Peiminine is a major biologically active component of Fritillaria thunbergii Miq that exhibits good anticancer, antiinflammatory, and anti-osteoclast effects. However, its effects on osteoporosis (OP) remain unknown. This study aimed to explore whether Peiminine was able to regulate osteogenesis and adipogenesis in ovariectomized (OVX) rat. The effects on the differentiation of bone marrow stem cells (BMSCs), function of Wnt/β-catenin pathway, ALP activity, calcium nodule deposition, as well as adipocyte formation in vitro by Peiminine at different concentrations, were detected. The curative effects of Peiminine on the ovariectomy-induced osteoporosis model by micro-CT and bone histomorphology assays were analyzed. The promotion of osteogenic differentiation and inhibition of adipogenic differentiation by Peiminine (5-40 μg/mL) was detected and the optimum concentration was 20 μg/mL. Mechanistically, Peiminine regulated the fate of BMSCs in vitro, and activated Wnt/β-catenin signaling pathway by restraining phosphorylation of β-catenin and promoting the nuclear translocation of β-catenin. Moreover, Peiminine prevented ovariectomy-induced osteoporosis by alleviating trabecular bone loss and inhibiting adipose formation. Our data suggested that Peiminine could attenuate ovariectomy-induced osteoporosis by alleviating trabecular bone loss and inhibiting adipose formation. These encouraging discoveries could lay the foundation for Peiminine to be a promising preventive treatment strategy for skeletal diseases, such as osteoporosis.

Mechanism of "Huang Qi-Yin Yang Huo" on the Treatment of Osteoporosis by Active Components Based on Network Pharmacology and Molecular Docking

Objective: To investigate the effect of Huang Qi-Yin Yang Huo on osteoporosis (OP) by means of network pharmacology and molecular docking, in order to provide a basis for its basic research and clinical application. Methods: The active components and targets of the drug pair were obtained by means of TCMSP database and literature supplement. OMIM, GeneCards, DisGeNet, TTD and DrugBank databases were used to screen the targets related to osteoporosis, and Wayne tool was used to obtain the intersection targets. CytoScape 3.7.2 software was used to construct the "drug-ingredient-disease" network and screen core components according to node-degree values. Protein interaction network (PPI) was constructed with STRING 11.5, and core targets were screened according to node-degree values. Metascape was used for gene ontology (GO) functional enrichment analysis and Kyoto Encyclopedia of Gene and Genes (KEGG) pathway enrichment analysis, and the interactions between core components and core targets were verified by molecular docking. Results: 46 kinds of active components were identified by drug pair screening, and 128 intersection targets were identified. The target protein enrichment pathways included MAPK signaling pathway, PI3K-Akt signaling pathway, HIF-1 signaling pathway and estrogen signaling pathway. The results of Molecular docking showed that the core components had good binding ability with the core target. Conclusion: Huang Qi-Yin Yang Huo may treat osteoporosis through multi-target and multi-pathway treatment, mainly regulating osteoblast differentiation, osteoclast inhibition, cell apoptosis and inflammation regulation, etc., providing a new idea and method for further research on the mechanism of osteoporosis in the future.

Deciphering the molecular mechanism underlying the effects of epimedium on osteoporosis through system bioinformatic approach.

Epimedium has gained widespread clinical application in Traditional Chinese Medicine, with the functions of promoting bone reproduction, regulating cell cycle and inhibiting osteoclastic activity. However, its precise cellular pharmacological therapeutic mechanism on osteoporosis (OP) remains elusive. This study aims to elucidate the molecular mechanism of epimedium in the treatment of OP based on system bioinformatic approach.Predicted targets of epimedium were collected from TCMSP, BATMAN-TCM and ETCM databases. Differentially expressed mRNAs of OP patients were obtained from Gene Expression Omnibus database by performing Limma package of R software. Epimedium-OP common targets were obtained by Venn diagram package for further analysis. The protein-protein interaction network was constructed using Cytoscape software. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were carried out by using clusterProfiler package. Molecular docking analysis was conducted by AutoDock 4.2 software to validate the binding affinity between epimedium and top 3 proteins based on the result of protein-protein interaction.A total of 241 unique identified epimedium targets were screened from databases, of which 62 overlapped with the targets of OP and were considered potential therapeutic targets. The results of Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis revealed that these targets were positive regulation of cell cycle, cellular response to oxidative stress and positive regulation of cell cycle process as well as cellular senescence, FoxO, PI3K-Akt, and NF-kappa B signaling pathways. Molecular docking showed that epimedium have a good binding activity with key targets.Our study demonstrated the multitarget and multi-pathway characteristics of epimedium on OP, which elucidates the potential mechanisms of epimedium against OP and provides theoretical basis for further drug development.

Manganese, iron, copper, and selenium co-exposure and osteoporosis risk in Chinese adults

Background & aimsPrevious experimental studies demonstrated that either deficient or excessive trace elements, such as manganese (Mn), iron (Fe), copper (Cu) and selenium (Se), are detrimental to bone health. Epidemiologic evidence for the effect of the four trace elements on osteoporosis (OP) risk remains inadequate. This cross-sectional study aimed to examine their associations with the OP risk among Chinese adults. MethodsConcentrations of Mn, Fe, Cu, and Se were measured in plasma using an inductively coupled plasma mass spectrometer among 627 Chinese adults aged ≥ 50 years. Individual effect of the four elements on OP risk was analyzed by logistic regression and Bayesian Kernel Machine Regression (BKMR) models. The latter model was also adopted to examine the exposure-response relationships and joint effects of the four elements on OP risk. ResultsThe median Mn, Fe, Cu, and Se levels were 4.78, 1026.63, 904.55, and 105.39 μg/L, respectively, in all participants. Inverse associations of Fe and Se levels with OP risk were observed in the logistic regression model. BKMR analysis revealed a U-shape pattern for the Fe-OP association, and a reduced OP risk in response to co-exposure of the four elements above the 50th percentiles but an elevated one in response to that below the 50th percentiles. Sex discrepancy existed in the findings. No interactions were found for the four elements affecting OP risk. ConclusionsCo-exposure to Mn, Fe, Cu, and Se was associated with improved bone density, where Fe contributed most to the beneficial effect. Further studies are needed to verify these findings and explore the underlying biological mechanism.

Total flavonoids of Rhizoma Drynariae combined with calcium attenuate osteoporosis by reducing reactive oxygen species generation.

In the present study, the effects of total flavonoids of Rhizoma Drynariae (TFRD) and calcium carbonate (CaCO3) on osteoporosis (OP) were assessed in a rat model of OP. For this purpose, 36 Sprague-Dawley rats, aged 3 months, were randomly divided into a group undergoing sham surgery (sham-operated group), model group (OP group), CaCO3 group (OP + CaCO3 group), TFRD group (OP + TFRD group), TFRD combined with CaCO3 group (OP + TFRD + CaCO3 group) and TFRD and CaCO3 combined with N-acetyl cysteine group (OP + TFRD + CaCO3 + NAC group). The rat model of OP was established by bilateral ovariectomy. The changes in bone mineral density (BMD), bone volume parameters and bone histopathology in the rats from each group were observed. The levels of serum reactive oxygen species, superoxide dismutase (SOD), malondialdehyde, glutathione peroxidase (GSH-Px), interleukin (IL)-6, IL-1β, TNF-α, and the levels of bone tissue runt-related transcription factor 2 (RUNX2), osteoprotegerin (OPG), osteocalcin (BGP), PI3K, p-PI3K, AKT, p-AKT, mammalian target of rapamycin (mTOR) and p-mTOR were measured in the rats of each group. The induction of OP was associated with a marked decrease in BMD, bone mineral content, bone volume fraction and trabecular thickness, and decreased serum levels of SOD and GSH-Px. Moreover, the expressions of RUNX2, OPG, BGP were downregulated and an upregulation of p-PI3K, p-AKT and p-mTOR were observed in osteoporotic rats. However, treatment with TFRD and CaCO3 restored all the aforementioned parameters to almost normal values. Furthermore, the findings on histopathological evaluation were consistent with the biochemical observations. Taken together, the findings of the present study demonstrated that TFRD and CaCO3 significantly increased the antioxidant capacity in rats with OP, increased BMD and reduced bone mineral loss, and may be useful for the prevention and treatment of OP.

Extracellular vesicles from GPNMB-modified bone marrow mesenchymal stem cells attenuate bone loss in an ovariectomized rat model

AimsThe efficacy of anti-osteoporotic treatments is still limited. Our study aimed to investigate the effect of extracellular vesicles (EVs) derived from bone marrow-derived MSCs (BMSCs) overexpressing glycoprotein non-melanoma clone B (GPNMB) on osteoporosis (OP). Main methodsLentiviral vector for GPNMB overexpression or its negative control was generated and transfected into BMSCs. EVs enriched with GPNMB (GPNMB-EVs) were extracted from GPNMB-modified BMSC-conditioned medium and then identified. Cellular uptake and proliferation were analyzed using the Dil-labeled assay and CCK-8 assay, respectively. Cytochemical staining, western blot, and RT-qPCR analysis were performed to assess the effect of GPNMB-EVs on osteogenic differentiation of BMSCs in vitro. Dickkopf-1 (DKK1) as the inhibitor was applied to explore the Wnt/β-catenin signaling pathway involved in the GPNMB-EV-induced osteogenic differentiation. In vivo experiments were conducted using an ovariectomized (OVX) rat model of postmenopausal osteoporosis, and then assessed the effect of GPNMB-EVs by micro-CT, and histological and immunohistochemical assays. Key findingsGPNMB-EVs were taken up by BMSCs, and they noticeably promoted the proliferation of BMSCs. Additionally, GPNMB-EVs activated the Wnt/β-catenin signaling to stimulate osteogenesis in BMSCs. In vivo examination showed that GPNMB-EVs remarkably improved trabecular bone regeneration and alleviated the osteoporotic phenotype in the OVX-induced rat model of OP. SignificanceEVs derived from GPNMB-modified BMSCs significantly stimulated the proliferation and osteogenic differentiation of BMSCs via the activation of Wnt/β-catenin signaling and attenuated the bone loss in the OVX-induced rat model of OP. Our findings suggest the promising potential of GPNMB-EVs as cell-free therapy for the treatment of OP.

Bortezomib Rescues Ovariectomy-Induced Bone Loss via SMURF-Mediated Ubiquitination Pathway.

A balance between bone formation by osteoblasts and bone resorption by osteoclasts is necessary to maintain bone health and homeostasis. As a cancer of plasma cells, multiple myeloma (MM) is accompanied with rapid bone loss and fragility fracture. Bortezomib has been used as a first-line for treating MM for decades. Recently, the potential protection of bortezomib on osteoporosis (OP) is reported; however, the specific mechanism involving bortezomib-mediated antiosteoporotic effect is undetermined. In the present study, we assessed the effects of in vitro bortezomib treatment on osteogenesis and osteoclastogenesis and the protective effect on bone loss in ovariectomized (OVX) mice. Our results indicated that bortezomib treatment increased osteogenic differentiation of MC3T3-E1 cells as evidenced by increased levels of matrix mineralization and osteoblast-specific markers. In bortezomib-treated bone marrow monocytes (BMMs), osteoclast differentiation was suppressed, substantiated by downregulated tartrate-resistant acid phosphatase- (TRAP-) positive multinucleated cells, areas of actin rings, pit formation, and osteoclast-specific genes. Mechanistically, bortezomib exerted a protective effect against OP through the Smad ubiquitination regulatory factor- (SMURF-) mediated ubiquitination pathway. Furthermore, in vivo intraperitoneal injection of bortezomib attenuated the bone microarchitecture in OVX mice. Accordingly, our findings corroborated that bortezomib might have future applications in the treatment of postmenopausal OP.

High-Throughput Metabolomics Method for Discovering Metabolic Biomarkers and Pathways to Reveal Effects and Molecular Mechanism of Ethanol Extract From Epimedium Against Osteoporosis.

Metabolomics is an effective strategy to explore the molecular mechanism of herbal medicine. Epimedium, a traditional Chinese herb from the Epimedium brevicornu Maxim., has a therapeutic effect on osteoporosis (OP), however the molecular mechanism of the anti-OP effect is uncle\\ar. Therefore, we investigated the pharmacological effect and action mechanism of ethanol extract of epimedium (Ext-epi) onOP rat model. The serum of OP rats was analyzed utilized UPLC-Q-TOF/MS metabolomics, and the potential biomarkers were screened and identified using multivariate data analysis systems and network databases. To further appraise the influence of Ext-epi on biological markers and metabolic pathways, and reveal the potential mechanism of Ext-epi on OP treatment. The results showed that 46 potential biomarkers were screened out and after intervention with Ext-epi extracts solution, 16 potential biomarkers were significantly recalled. Further pathway experiments showed that key pathway analysis include sarachidonic acid metabolism, glycerolphospholipid metabolism as potential targets which is related with the efficacy of Ext-epi protect against OP. These results explain the correlation between metabolites and molecular mechanisms, which is of great significance for understanding the intervention of Ext-epi on OP. In short, based on UPLC-Q-TOF/MS metabolomics may provide effective strategies for understanding the pathogenesis of diseases and evaluating the intervention effect of natural products.

Let-7b downgrades CCND1 to repress osteogenic proliferation and differentiation of MC3T3-E1 cells: An implication in osteoporosis.

The aim of this study was to reveal the effect of let-7b on osteoporosis (OP). Synthetic let-7b mimics or inhibitors were transfected into MC3T3-E1 cells. The expression of let-7b in MC3T3-E1 and its effect on cell viability, apoptosis, and the apoptosis-related proteins (Bcl-2, Bax, and cleaved caspase-9) were tested by CCK-8 assay, flow cytometry and Western blot, severally. The osteogenic differentiation markers (Runx2 and Osterix) and Wnt/β-catenin pathway related markers (β-catenin and C-myc) were detected by qRT-PCR and Western blot. The relationships between let-7b and cyclin D1 (CCND1) were confirmed by luciferase reporter assay. The differentiation and mineralization of MC3T3-E1 cells were analyzed by alkaline phosphatase (ALP) activity assay and alizarin red staining. The outcomes indicated that overexpression/ablation of let-7b repressed/facilitated MC3T3-E1 cell viability and accelerated/suppressed MC3T3-E1 cell apoptosis. Besides, a remarkable decrease/augment of Bcl-2 protein expression and the distinct fortify/reduction of Bax and cleaved caspase-9 expression levels were observed in let-7b mimics/inhibitors group in MC3T3-E1 cells. Moreover, we discovered that let-7b overexpression/ablation retrained/facilitated the mRNA and protein expression of Runx2 and Osterix. It was confirmed that CCND1 was a downstream target of let-7b and was negatively modulated by let-7b. In addition, high-expression/deficiency of let-7b inhibited/increased the expression levels of β-catenin and C-myc in MC3T3-E1 cells. Taken together, our study revealed that let-7b overexpression/depletion repressed/accelerated MC3T3-E1 cell proliferation, differentiation, and mineralization while promoted/suppressed MC3T3-E1 cell apoptosis through targeting CCND1, which might be adjusted by Wnt/β-catenin pathway. Our findings might offer a basis for developing novel targets for OP treatment.

Network pharmacology approach to elucidate possible action mechanisms of Sinomenii Caulis for treating osteoporosis

Ethnopharmacological relevanceSinomenii Caulis (SC) is a well-konwn traditional Chinese medicine used for treatment of rheumatoid arthritis (RA), dermatophytosis and paralysis. Patients with RA are usually secondary to osteoporosis, but the potential protective effect of SC on osteoporosis (OP) is seldom reported and its possible action mechanism is little known. AimThe purpose of this study was to demonstrate the anti-osteoporosis effects of SC extract and alkaloids in prednisolone (Pre)-induced OP of zebrafish, and then to explore the potential mechanism of SC on system level by network pharmacology. MethodsFirstly, zebrafish OP model was established to investigate the anti-osteoporosis effect of SC. Secondly, the targets of SC and OP from multiple databases were collected, and Compound-Target-Pathway network based on protein-protein interaction (PPI) was constructed. Moreover, gene enrichment and annotation were performed via the DAVID server. Finally, the reliability of the network pharmacology prediction results in Pre-induced OP of zebrafish was verified by qRT-PCR. ResultsThe results indicated that SC extract and alkaloids have remarkable ability to promote bone formation of cranial bones and reduce TRAP contents in Pre-induced OP of zebrafish. 32 OP-related ingredients in SC and 77 OP-related targets were screened from multiple databases, and 15 OP-related pathways were enriched by the KEGG database. Further experimental validation indicated that SC extract and alkaloids could regulate the expression of MAPK14, CASP3, CXCL8, IL-1β, IL6, PTGS2, TNF-α, ESR1, and MMP9 for treatment of OP. ConclusionIn summary, we conducted an integrative analysis to provide convincing evidence that SC may partially alleviate OP by inhibiting pro-inflammatory cytokines and regulating of RANK/RANKL/OPG system.

Recommendations by the Spanish Society of Rheumatology on Osteoporosis.

To update the recommendations on osteoporosis (OP) of the Spanish Society of Rheumatology (SER) based on the best possible evidence. A panel of nine expert rheumatologists in OP was created, previously selected by the SER through an open call. The phases of the work were: identification of the key areas for updating the previous consensus, analysis and synthesis of the scientific evidence (using the SIGN levels of evidence) and formulation of recommendations based on this evidence and consensus techniques. This revision of the recommendations implies an update in the diagnostic evaluation and treatment of OP. It proposes some criteria to consider the high risk of fracture and some indications to start treatment. The recommendations also address issues related to the safety of treatments and the management of special situations such as inflammatory diseases and treatment with glucocorticoids. We present an update of SER recommendations on OP.

Comparison of bone biomechanical properties after bone marrow mesenchymal stem cell or alendronate treatment in an osteoporotic animal model.

The aim of this study was to explore the effects of bone marrow mesenchymal stem cells (BMMSCs) and alendronate sodium (ALN) intervention on osteoporosis (OP). Sixty-eight 6-month-old healthy female Sprague Dawley (SD) rats were used to generate an OP model by removal of the ovaries. After 12 weeks, rats were treated with BMMSCs (BMMSC group) or ALN (ALN group) for 5 weeks. Serum type I collagen C terminal peptide (CTX_1), procollagen type I N-terminal propeptide (PINP), and bone alkaline phosphatase (BALP) were tested along with the femur bone density and other properties, including bone mineral density (BMD), BALP, percent trabecular area (BV/TV), trabecular thickness (Tb.Th), trabecular number (TbN), maximum load, maximum stress, maximum strain, and elastic modulus. BMD, BALP, BV/TV, Tb.Th, TbN, maximum load, maximum stress, maximum strain, and elastic modulus values were higher in the BMMSC group versus the ALN group relative to the control group (p < 0.05); CTX_1, PINP, trabecular separation (Tb.Sp), and osteoclast number (OC.N) were lowest in the BMMSC group versus the ALN group relative to the control group (p < 0.05). Both BMMSCs and ALN could improve the metabolic function and bone quality in osteoporotic mice while restoring the strength and toughness of bones. The intervention effects of BMMSCs are better than ALN in this model.

Recommendations by the Spanish Society of Rheumatology on Osteoporosis

ObjectiveTo update the recommendations on osteoporosis (OP) of the Spanish Society of Rheumatology (SER) based on the best possible evidence. MethodsA panel of nine expert rheumatologists in OP was created, previously selected by the SER through an open call. The phases of the work were: identification of the key areas for updating the previous consensus, analysis and synthesis of the scientific evidence (using the SIGN levels of evidence) and formulation of recommendations based on this evidence and consensus techniques. ResultsThis revision of the recommendations implies an update in the diagnostic evaluation and treatment of OP. It proposes some criteria to consider the high risk of fracture and some indications to start treatment. The recommendations also address issues related to the safety of treatments and the management of special situations such as inflammatory diseases and treatment with glucocorticoids. ConclusionsWe present an update of SER recommendations on OP.

Effect of Bushen Jiangu decoction on ovariectomyinduced osteoporosis in rats

Purpose: This study aimed to determine the therapeutic effect of Bushen Jiangu Decoction (BJD) on osteoporosis (OS) in rats.Methods: The animals were divided into the following groups: control group, rats received no treatment; ovariectomy (OVX) group, rats subjected to OVX surgery and were treated with normal saline; OVX + Fosamax group, rats that received OVX and were treated with 2 mg/kg/week of Fosamax; low-dose BJD (40 mg/kg/day), medium-dose BJD (80 mg/kg/day) and high-dose BJD (160 mg/kg/day) groups, where rats received OVX surgery with BJD doses of 40, 80 and 160 mg/kg/day, respectively. At four weeks after treatment with OVX, Fosamax or BJD was orally administered for four months. Bone mineral density (BMD) was assessed, while serum hormone, serum levels of follicle-stimulating hormone (FSH), alkaline phosphatase (ALP), estradiol (E2), luteinizing hormone (LH), osteocalcin (OC) and telopeptides of collagen type I (CTx) were measured by enzyme linked immunosorbent assay (ELISA).Results: The results demonstrated that the reduced BMDs of L4 femurs and vertebrae were inhibited by BJD. Furthermore, BJD significantly elevated the serum levels of FSH, E2 and LH in OS rats. Furthermore, the serum CTx, ALP and OC levels of these rats dramatically decreased, when compared to the OVX group.Conclusion: These findings suggest that BJD can improve OVX-induced OS.Keywords: Bushen Jiangu decoction, Osteoporosis, Bone mineral density, Serum biochemistry