Postmenopausal osteoporosis

Machine learning model for osteoporosis diagnosis based on bone turnover markers

To assess the diagnostic utility of bone turnover markers (BTMs) and demographic variables for identifying individuals with osteoporosis. A cross-sectional study involving 280 participants was conducted. Serum BTM values were obtained from 88 patients with osteoporosis and 192 controls without osteoporosis. Six machine learning models, including extreme gradient boosting (XGBoost), light gradient boosting machine (LGBM), CatBoost, random forest, support vector machine, and k-nearest neighbors, were employed to evaluate osteoporosis diagnosis. The performance measures included the area under the receiver operating characteristic curve (AUROC), F1-score, and accuracy. After AUROC optimization, LGBM exhibited the highest AUROC of 0.706. Post F1-score optimization, LGBM's F1-score was improved from 0.50 to 0.65. Combining the top three optimized models (LGBM, XGBoost, and CatBoost) resulted in an AUROC of 0.706, an F1-score of 0.65, and an accuracy of 0.73. BTMs, along with age and sex, were found to contribute significantly to osteoporosis diagnosis. This study demonstrates the potential of machine learning models utilizing BTMs and demographic variables for diagnosing preexisting osteoporosis. The findings highlight the clinical relevance of accessible clinical data in osteoporosis assessment, providing a promising tool for early diagnosis and management.

The potential benefits and mechanisms of protein nutritional intervention on bone health improvement

Osteoporosis commonly occurs in the older people and severe patients, with the main reason of the imbalance of bone metabolism (the rate of bone resorption exceeding the rate of bone formation), resulting in a decrease in bone mineral density and destruction of bone microstructure and further leading to the increased risk of fragility fracture. Recent studies indicate that protein nutritional support is beneficial for attenuating osteoporosis and improving bone health. This review summarized the classical mechanisms of protein intervention for alleviating osteoporosis on both suppressing bone resorption and regulating bone formation related pathways (promoting osteoblasts generation and proliferation, enhancing calcium absorption, and increasing collagen and mineral deposition), as well as the potential novel mechanisms via activating autophagy of osteoblasts, altering bone related miRNA profiles, regulating muscle-bone axis, and modulating gut microbiota abundance. Protein nutritional intervention is expected to provide novel approaches for the prevention and adjuvant therapy of osteoporosis.

Exosomal miR-29a Derived from Bone Marrow Mesenchymal Stem Cells Promotes Mouse Bone Development and Formation

Bone undergoes constant remodeling during development, and the maintenance of its function requires a dynamic balance between bone formation and resorption by osteoclasts. With unique bone resorption capabilities, as large multinucleated cells, osteocytes participate in bone remodeling and they are produced by the mononuclear/macrophage cells under activation of Wnt and Runx2. The mechanism underlying osteogenesis remains unclear. We investigated the impact of exosomal miR-29a derived from BMSCs on bone development and formation. In this study, BMSCs were transfected and then injected into mice followed by analysis of femur and skull development and regeneration by HE staining and CT scanning, and the expression of DKK1, Runx-2, and osteogenic biomarkers (Osterix, Satb2, ALP, and BSP) by western blot and RT-qPCR. Compared with mice in miR-29a inhibitor group, the femur and skull of mice in miRNA NC group were more complete. miR-29a derived from BMSCs induced a decrease of DKK1 expression and increase of the expression of β-catenin and osteogenic transcription factors. In conclusion, this study demonstrates that BMSC-derived exosomes miR-29a facilitates osteogenesis in mice through inhibition of DKK1 expression.

Bone Marrow Mesenchymal Stem Cell-Exosomes (BMSC-ExO) Promote Osteogenic Differentiation In Vitro and Osteogenesis In Vivo by Regulating miR-318/Runt-Related Transcription Factor 2 (RUNX2)

Primary osteoporosis (PMOP) is characterized by bone mass reduction and bone microstructure destruction, increased bone fragility and prone to fracture, which is partially caused by ovarian dysfunction and decreased estrogen content. Bone marrow mesenchymal stem cell exosomes (BMSC-ExO) can improve PMOP. In this study, BMSC-EXO was used to study the role and function of miR-318 and Runx2 in PMOP. Human osteogenitor cells were isolated from PMOP patients with primary osteoporosis. After BMSC-exo treatment, miR-318 and Runx 2 level was tested by RT-qPCR and Western blot. In addition, mice in OVX group were treated with BMSC-ExO (bilateral ovaries were removed) to observe the effect of BMSC-ExO on bone tissue. Our results showed that BMSC-exo treatment significantly decreased miR-318 level, upregulated RUNX2 expression and increased ALP activity. In addition, BMSC-exo administration ameliorated the declined bone mass and bone formation in osteoporotic femurs in OVX mice. In conclusion, BMSC-Exo enhances Runx2 levels by down-regulation of miR-318, thereby promoting osteogenic differentiation of osteogenitor cells, providing new potential therapeutic targets for treating PMOP.

Hospital-wide surveillance of fracture risk assessment by both FRAX and medication patterns in acute care hospital

To identify patients at a high risk for primary and secondary osteoporotic fractures using fracture risk assessments performed using the current method and the proposed method, in an acute care hospital and to identify departments where high-risk patients are admitted. This retrospective study included patients aged 40-90 years who were hospitalized at Fujita Health University Hospital. We collated the clinical data and prescriptions of all study participants. We also gathered data pertaining to risk factors according to Fracture Risk Assessment Tool (FRAX). Of the 1,595 patients, the mean number of major osteoporotic fracture risk predicted using FRAX was 11.73%. The department of rheumatology showed the highest fracture risk (18.55 ± 16.81) and had the highest number of patients on medications that resulted in reduced bone mineral density (1.07 ± 0.98 medication). Based on the FRAX, the proportion of patients in the high-risk group in this department was significantly higher compared with those in the remaining departments with respect to glucocorticoid administration, rheumatoid arthritis, and secondary osteoporosis. However, the departments included in the high-risk group were not necessarily the same as the departments included in the top group, based on the administered medications. FRAX score is calculated based on various risk factors; however, only glucocorticoid corresponds to medications. We should focus on medication prescription patterns in addition to FRAX to improve fracture risk assessment in hospital-wide surveillance. Therefore, we recommend the use of FRAX along with the prescribed medications to identify departments that admit high-risk patients.

A Risk Assessment Tool for Identifying Osteoporosis in Older Women with Type 2 Diabetes Mellitus

PURPOSE

To develop a simple and clinically useful assessment tool for osteoporosis in older women with type 2 diabetes mellitus (T2DM).

METHODS

A total of 601 women over 60 years of age with T2DM were enrolled in this study. The levels of serum sex hormones and bone metabolism markers were compared between the osteoporosis and non-osteoporosis groups. The least absolute shrinkage and selection operator regularization (LASSO) model was applied to generate a risk assessment tool. The risk score formula was evaluated using receiver operating characteristic analysis and the relationship between the risk score and the bone mineral density (BMD) and T-value were investigated.

RESULTS

Serum sex hormone-binding globulin (SHBG), cross-linked C-telopeptide of type 1 collagen (CTX), and osteocalcin (OC) were significantly higher in the osteoporosis group. After adjustment for age and body mass index (BMI), SHBG was found to be correlated with the T-value or BMD. Then, a risk score was specifically generated with age, BMI, SHBG, and CTX using the LASSO model. The risk score was significantly negatively correlated with the T-value and BMD of the lumbar spine, femoral neck, and total hip (all P<0.05).

CONCLUSION

A risk score using age, BMI, SHBG, and CTX performs well for identifying osteoporosis in older women with T2DM.

Increased Potential of Bone Formation with the Intravenous Injection of a Parathyroid Hormone-Related Protein Minicircle DNA Vector

Osteoporosis is commonly treated via the long-term usage of anti-osteoporotic agents; however, poor drug compliance and undesirable side effects limit their treatment efficacy. The parathyroid hormone-related protein (PTHrP) is essential for normal bone formation and remodeling; thus, may be used as an anti-osteoporotic agent. Here, we developed a platform for the delivery of a single peptide composed of two regions of the PTHrP protein (1–34 and 107–139); mcPTHrP 1–34+107–139 using a minicircle vector. We also transfected mcPTHrP 1–34+107–139 into human mesenchymal stem cells (MSCs) and generated Thru 1–34+107–139-producing engineered MSCs (eMSCs) as an alternative delivery system. Osteoporosis was induced in 12-week-old C57BL/6 female mice via ovariectomy. The ovariectomized (OVX) mice were then treated with the two systems; (1) mcPTHrP 1–34+107–139 was intravenously administered three times (once per week); (2) eMSCs were intraperitoneally administered twice (on weeks four and six). Compared with the control OVX mice, the mcPTHrP 1–34+107–139-treated group showed better trabecular bone structure quality, increased bone formation, and decreased bone resorption. Similar results were observed in the eMSCs-treated OVX mice. Altogether, these results provide experimental evidence to support the potential of delivering PTHrP 1–34+107–139 using the minicircle technology for the treatment of osteoporosis.

Bergapten: A review of its pharmacology, pharmacokinetics, and toxicity

Bergapten is a natural furocoumarin, also known as 5-methoxypsoralen, and its medicinal value has been paid more and more attention. By sorting out the pharmacological literature of bergapten, we found that bergapten has a wide range of pharmacological effects, including neuroprotection, organ protection, anticancer, antiinflammatory, antimicrobial, and antidiabetes effects. However，bergapten has complex impacts on the hepatic metabolic enzyme. Moreover, pharmacokinetic studies showed that bergapten has higher absolute bioavailability and can cross the blood-brain barrier and has a great potential for treating brain disease, but the mechanism needs further clarification to make greater use of its ability to treat brain diseases. Furthermore, the phototoxicity of bergapten combined with ultraviolet light has always been mentioned. In view of its wide range of pharmacological activities, bergapten is expected to be a potential drug candidate for the treatment of diabetes and diabetes-induced osteoporosis, epilepsy, Alzheimer's disease, depression, and cancer. However, further studies are needed to elucidate its molecular mechanisms and targets. The phototoxicity of bergapten as a side effect should be further avoided. On the other hand, the photoactivation of bergapten in the anticancer aspect can be better utilized.

Beraprost ameliorates postmenopausal osteoporosis by regulating Nedd4-induced Runx2 ubiquitination

Bone health requires adequate bone mass, which is maintained by a critical balance between bone resorption and formation. In our study, we identified beraprost as a pivotal regulator of bone formation and resorption. The administration of beraprost promoted differentiation of mouse bone mesenchymal stem cells (M-BMSCs) through the PI3K–AKT pathway. In co-culture, osteoblasts stimulated with beraprost inhibited osteoclastogenesis in a rankl-dependent manner. Bone mass of p53 knockout mice remained stable, regardless of the administration of beraprost, indicating that p53 plays a vital role in the bone mass regulation by beraprost. Mechanistic in vitro studies showed that p53 binds to the promoter region of neuronal precursor cell-expressed developmentally downregulated 4 (Nedd4) to promote its transcription. As a ubiquitinating enzyme, Nedd4 binds to runt-related transcription factor 2 (Runx2), which results in its ubiquitination and subsequent degradation. These data indicate that the p53–Nedd4–Runx2 axis is an effective regulator of bone formation and highlight the potential of beraprost as a therapeutic drug for postmenopausal osteoporosis.

Anti-inflammatory activity of psoralen in human periodontal ligament cells via estrogen receptor signaling pathway

Psoralen is one of the most effective ingredients extracted from the Chinese herb, Psoralea corylifolia L. Studies have found that psoralen has anti-inflammatory and estrogen-like effects; however, little research has been conducted to elucidate the mechanisms underlying these effects. Through the molecule docking assay, psoralen was found to have a better combination with ERα than ERβ. In human periodontal ligament cells, psoralen was found to upregulate the estrogen target genes (e.g., CTSD, PGR, TFF1) and down-regulate the expression of inflammatory cytokines (TNF-α, IL-1β, IL-6 and IL-8) stimulated by P. gingivalis LPS, as well as TLR4-IRAK4-NF-κb signaling pathway proteins. These effects were reversed by the ER antagonist ICI 182780. These results indicated that psoralen may exert anti-inflammatory effects as an agonist to ER, which could provide a theoretical basis for the use of psoralen for adjuvant therapy and prevention of periodontitis.

The changes in bone turnover markers of female systemic lupus erythematousus patients without glucocorticoid

OBJECTIVES

SLE is a chronic autoimmune disease, which can affect the level of bone metabolism and increase the risk of osteoporosis and fracture. The purpose of this research is to study the effect of SLE on bone turnover markers without the influence of glucocorticoids.

METHODS

A total of 865 female subjects were recruited from Zhejiang Provincial People's Hospital and the First Hospital of Jiaxing, including 391 SLE patients without the influence of glucocorticoids and 474 non-SLE people. We detected Bone turnover markers including amino-terminal propeptide of type 1 procollagen (P1NP), C-terminal turnover of β - I collagen (β-CTX), N-terminal midfragment of osteocalcin (NMID) and 25(OH)D, and analyzed the difference in Bone turnover markers between the SLE group and the control group, as well as the influence of age and season on bone metabolism in female SLE patients.

RESULTS

In the SLE group, the average age was 43.93±13.95 years old. In the control group, the average age was 44.84±11.42 years old. There was no difference between the two groups (t = 1.03, P = 0.30). P1NP, NMID and 25(OH)D in the SLE group were significantly lower than those in the control group (Z = 8.44, p < 0.001; Z = 14.41, p < 0.001; Z = 2.19, p = 0.029), and β-CTX in the SLE group was significantly higher than that in the control group (Z = 2.61, p = 0.009). In addition, the levers of β-CTX, NMID, P1NP and 25(OH)D in older SLE female patients were statistically significantly higher than those in younger (ρ = 0.104, p = 0.041; ρ = 0.223, p < 0.001; ρ = 0.105, p = 0.038; ρ = 0.289, p < 0.001). Moreover, β-CTX reached a high value in summer and PINP reached a low value in winter.

CONCLUSION

The bone formation markers of female SLE patients without glucocorticoid were lower than those of normal people and the bone resorption marker was higher than that of normal people. The 25 (OH) D of female SLE patients without glucocorticoid was lower than that of normal people. The risk of osteoporosis and fracture may be higher in elderly women with SLE. The bone resorption level of female SLE patients is high in summer and the bone formation level is low in winter.

Zanthoxylum piperitum alleviates the bone loss in osteoporosis via inhibition of RANKL-induced c-fos/NFATc1/NF-κB pathway

BACKGROUND

The fruit of Zanthoxylum piperitum (ZP) is an herbal medicine as well as a spice agent in Asia to treat carminative, stomachic, anthelmintic and degenerative diseases. Z. piperitum was reported to have anti-oxidant, anti-inflammatory, anti-osteoarthritic and osteosarcoma proliferation-control effects.

PURPOSE AND STUDY DESIGN

This study was conducted to determine the anti-osteoporotic effects and mechanisms of action of ZP.

METHODS

Female ICR mice underwent ovariectomies (OVX) and were orally administered ZP at 1, 10 and 100 mg/kg for 6 weeks. The femoral and tibial bones were assessed by dual-energy X-ray absorptiometry and histology to analyze the bone mineral density (BMD) and the number of osteoclasts. Raw 264.7 cells were stimulated by 100 ng/ml receptor activator of nuclear factor-κB ligand (RANKL) for 7 days in the presence of ZP. RANKL-induced signaling molecules were analyzed in osteoclasts.

RESULTS

The levels of femoral and tibial BMD were significantly increased by ZP administration. Serum biomarkers such as osteocalcin, calcium, alkaline phosphatase and bone-specific alkaline phosphatase concentrations were markedly recovered to normal levels in ZP-treated osteoporotic mice. In addition, the number of osteoclasts in the head, trochanter and body of the femur was obviously decreased in the ZP treatment groups. Moreover, ZP treated-cells showed a reduction in the number of TRAP-positive multinuclear cells in RANKL-stimulated Raw 264.7 cells. ZP decreased the RANKL-activated NFATc1 and c-fos, transcription factors of osteoclast formation. The nuclear translocation of NF-κB and phosphorylation of ERK42/44 were inhibited by the ZP treatment in RANKL-induced osteoclasts.

CONCLUSION

Collectively, ZP exerts its inhibitory effect against bone resorption by regulating RANKL-mediated c-fos/NFATc1/NF-κB in osteoclast. ZP may prove to be a therapeutic agent for osteoporosis.

Diosmetin reduces bone loss and osteoclastogenesis by regulating the expression of TRPV1 in osteoporosis rats

Background

Osteoporosis is a systemic skeletal disorder and occurs frequently in postmenopausal women and older men. This study aimed to examine whether diosmetin (DIO) can relieve estrogen deficiency—induced osteoporosis and to explore the underlying mechanisms of this potential effect.

Methods

Forty-nine Sprague-Dawley (SD) rats were divided into seven groups. Six groups underwent bilateral ovariectomy (OVX), while the sham group underwent ovarian exposure surgery. DIO and evodiamine were administered 3 days before surgery, and then subcutaneously every 3 days for 3 months in the following fashion: group I, DIO (100 mg/kg); group II, OVX; group III, OVX + DIO (50 mg/kg); group IV, OVX + DIO (100 mg/kg); group V, OVX + evodiamine (10 mg/kg) group; group VI, OVX + DIO (100 mg/kg) + evodiamine (10 mg/kg) group. Bone histopathological damage, bone loss, osteoclast production, and the expression level of transient receptor potential vanilloid 1 (TRPV1) were detected.

Results

Compared with the sham group, the expression of bone resorption–related genes, osteoclast-associated receptor (OSCAR) (1.00%±0.16% versus 4.5%±0.28%, **, P<0.01) and tartrate-resistant acid phosphatase (TRAP) (2.0%±0.6% versus 18.00±1.2%, ***, P<0.001), was increased significantly. The protein level of osteogenic marker proteins, osterix (Osx) (1.0%±0.1% versus 0.03%±0.01%, **, P<0.01) and type 1 collagen (COL1A1) (1.0%±0.13% versus 0.13%±0.05%, **, P<0.01) was decreased significantly with the increase of TRPV1 (1.0%±0.15% versus 2.89%±0.28%, **, P<0.01) protein level. Notably, DIO can alleviate some abnormal symptoms related to osteoporosis.

Conclusions

DIO can relieve typical osteoporosis symptoms in an OVX osteoporosis rat model. The underlying mechanism may be associated with the downregulation of TRPV1.

AEG-1 deletion promotes cartilage repair and modulates bone remodeling-related cytokines via TLR4/MyD88/NF-κB inhibition in ovariectomized rats with osteoporosis

Background

Osteoporosis is a systemic skeletal disorder that can impact a variety of bones throughout the body. Astrocyte-elevated gene-1 (AEG-1) is involved in multiple pro-tumorigenic functions and participates in various inflammatory reactions. However, whether it has an impact on osteoporosis-related cartilage repair and bone remodeling remains unknown.

Methods

We utilized an ovariectomy mouse model with AEG-1 deletion to investigate the role of AEG-1 in osteoporosis. The mRNA level of AEG-1 was detected by RT-PCR, bone markers, bone volume/total volume (BV/TV), trabecular bone surface/bone volume (BSA/BV) and trabecular bone thickness (Tb. Th) were detected by micro computed tomography (µCT), bone injury was observed by HE and alcian blue staining. The contents of IL-6, IL-17, iNOS and IL-10 in peripheral blood of the three groups were detected by ELISA. The expression of OSX, coi1a1, OC, TLR4, MyD88 and NF-κB were detected by Western Blot.

Results

µCT revealed increased bone volume in the AEG-1 knockout (KO) ovariectomy (OVX) group compared to the wildtype (WT) OVX group 4 weeks after surgery, indicating restored bone formation after AEG-1 deletion. Flow sorting revealed that AEG-1 deletion inhibited the production of inflammatory factors. Western blot demonstrated activation of the TLR4/MyD88/NF-κB pathway after LPS exposure, which was reduced by AEG-1 deletion. AEG-1 deletion also improved lipopolysaccharide (LPS) induced adverse reactions.

Conclusions

Taken together, these findings indicate that AEG-1 deletion improves cartilage repair and bone remodeling during osteoporosis, which may partly occur through the inhibition of the TLR4/MyD88/NF-κB signaling pathway.

MiR-23b-3p promotes postmenopausal osteoporosis by targeting MRC2 and regulating the Wnt/β-catenin signaling pathway

Postmenopausal osteoporosis (PMOP) is one of the most common metabolic bone diseases in postmenopausal women. Increasing evidence has indicated that microRNAs (miRNAs) play vital regulatory roles during osteoporosis progression. This study aimed to investigate the potential function of miR-23b-3p in the osteogenic differentiation of human bone marrow mesenchymal stem cells (hMSCs). PMOP was induced in mice by bilateral ovariectomy. X-ray absorptiometry was applied to detect BMD and BMC in PMOP mice. Luciferase reporter assay and RIP assay were utilized to investigate the relationship between miR-23b-3p and MRC2. We found the upregulation of miR-23b-3p in bone tissues of PMOP mice. Silencing of miR-23b-3p relieved PMOP in mice. Moreover, miR-23b-3p knockdown facilitated the osteogenic differentiation of hMSCs by increasing the expression of Runx2, OCN, Osterix and promoting ALP activity. Mechanistically, MRC2 is a downstream target gene of miR-23b-3p. MRC2 knockdown significantly rescued the promoting effect of lenti-miR-23b-3p inhibitor on osteogenic differentiation of hMSCs. Furthermore, miR-23b-3p targeted MRC2 to inhibit the Wnt/β-catenin pathway during the osteogenic differentiation of hMSCs. In summary, inhibition of miR-23b-3p alleviates PMOP by targeting MRC2 to inhibit the Wnt/β-catenin signaling, which may provide a novel molecular insight for osteoporosis therapy.

Application of machine learning approaches for osteoporosis risk prediction in postmenopausal women

Many predictive tools have been reported for assessing osteoporosis risk. The development and validation of osteoporosis risk prediction models were supported by machine learning.

INTRODUCTION

Osteoporosis is a silent disease until it results in fragility fractures. However, early diagnosis of osteoporosis provides an opportunity to detect and prevent fractures. We aimed to develop machine learning approaches to achieve high predictive ability for osteoporosis risk that could help primary care providers identify which women are at increased risk of osteoporosis and should therefore undergo further testing with bone densitometry.

METHODS

We included all postmenopausal Korean women from the Korea National Health and Nutrition Examination Surveys (KNHANES V-1, V-2) conducted in 2010 and 2011. Machine learning models using methods such as the k-nearest neighbors (KNN), decision tree (DT), random forest (RF), gradient boosting machine (GBM), support vector machine (SVM), artificial neural networks (ANN), and logistic regression (LR) were developed to predict osteoporosis risk. We analyzed the effect of applying the machine learning algorithms to the raw data and featuring the selected data only where the statistically significant variables were included as model inputs. The accuracy, sensitivity, specificity, and area under the receiver operating characteristic curve (AUROC) were used to evaluate performance among the seven models.

RESULTS

A total of 1792 patients were included in this study, of which 613 had osteoporosis. The raw data consisted of 19 variables and achieved performances (in terms of AUROCs) of 0.712, 0.684, 0.727, 0.652, 0.724, 0.741, and 0.726 for KNN, DT, RF, GBM, SVM, ANN, and LR with fivefold cross-validation, respectively. The feature selected data consisted of nine variables and achieved performances (in terms of AUROCs) of 0.713, 0.685, 0.734, 0.728, 0.728, 0.743, and 0.727 for KNN, DT, RF, GBM, SVM, ANN, and LR with fivefold cross-validation, respectively.

CONCLUSION

In this study, we developed and compared seven machine learning models to accurately predict osteoporosis risk. The ANN model performed best when compared to the other models, having the highest AUROC value. Applying the ANN model in the clinical environment could help primary care providers stratify osteoporosis patients and improve the prevention, detection, and early treatment of osteoporosis.

Comparison of efficacy and safety of Chinese patent medicine in the treatment of postmenopausal osteoporosis: A protocol for systematic review and network meta-analysis

BACKGROUND

Postmenopausal osteoporosis (PMOP) is the focus and difficult problem in the world at present, and we found that Chinese patent medicine(CPM) shown a more miraculous effect. Many kinds of Chinese patent medicine have been proved to be effective in the treatment of this disease, but it is still unclear which kind of Chinese patent medicine has the best effect. Therefore, we propose a network meta-analysis (NMA) protocol to observe the efficacy of various CPM for this disease and provide guidance for clinical practice.

METHODS

We will use the NMA method to complete this study. First, all the randomized controlled trials of CPM or CPM combined with western medicine in the treatment of PMOP were collected by searching all online Chinese and English databases. The information time limit is from the establishment of the database to August 30, 2020. Then 2 staff members will sift through all the literature and analyze the data using Stata and Winbugs.

RESULTS

Through this analysis, we will observe and rank the clinical effects of different CPM for PMOP. The main evaluation indexes include: New fracture, Quality of life, Severe side effects, Death from all causes. Secondary outcome indicators include Bone Mineral density, clinical efficiency, and some laboratory indicators, such as estradiol, serum calcium, serum, etc. CONCLUSION:: This study will rank the therapeutic effects of various proprietary Chinese medicines in the treatment of PMOP, which will be helpful in improving the PMOP treatment regimen.INPLASY registration number: INPLASY202090047.

Dehydroepiandrosterone and age-related musculoskeletal diseases: Connections and therapeutic implications

Musculoskeletal disorders related to ageing are one of the most common causes of mortality and morbidity among elderly individuals worldwide. The typical constitutive components of the musculoskeletal system, including bone, muscle, and joints, gradually undergo a process of tissue loss and degeneration as a result of life-long mechanical and biological stress, ultimately leading to the onset of a series of age-related musculoskeletal diseases, including osteoporosis (OP), sarcopenia, and osteoarthritis (OA). Dehydroepiandrosterone (DHEA), a precursor of androgen secreted mainly by the adrenal gland, has attracted much attention as a marker for senescence due to its unique age-related changes. This pre-hormone has been publicly regarded as an "antidote for ageing" because of its favourable effect against a wide range of age-related diseases, such as Alzheimer disease, cardiovascular diseases, immunosenescence and skin senescence, though its effect on age-related musculoskeletal diseases has been explored to a lesser extent. In the present review, we summarized the action of DHEA against OP, sarcopenia and OA. Extensive detailed descriptions of the pathogenesis of each of these musculoskeletal disorders are beyond the scope of this review; instead, we aim to highlight the association of changes in DHEA with the processes of OP, sarcopenia and OA. A special focus will also be placed on the overlapping pathogeneses among these three diseases, and the molecular mechanisms underlying the action of DHEA against these diseases are discussed or postulated.

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.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS/AMERICAN COLLEGE OF ENDOCRINOLOGY CLINICAL PRACTICE GUIDELINES FOR THE DIAGNOSIS AND TREATMENT OF POSTMENOPAUSAL OSTEOPOROSIS-2020 UPDATE

Objective: The development of these guidelines is sponsored by the American Association of Clinical Endocrinologists (AACE) Board of Directors and American College of Endocrinology (ACE) Board of Trustees and adheres with published AACE protocols for the standardized production of clinical practice guidelines (CPGs). Methods: Recommendations are based on diligent reviews of the clinical evidence with transparent incorporation of subjective factors, according to established AACE/ACE guidelines for guidelines protocols. Results: The Executive Summary of this 2020 updated guideline contains 52 recommendations: 21 Grade A (40%), 24 Grade B (46%), 7 Grade C (14%), and no Grade D (0%). These detailed, evidence-based recommendations allow for nuance-based clinical decision-making that addresses multiple aspects of real-world care of patients. The evidence base presented in the subsequent Appendix provides relevant supporting information for the Executive Summary recommendations. This update contains 368 citations: 123 (33.5%) evidence level (EL) 1 (highest), 132 (36%) EL 2 (intermediate), 20 (5.5%) EL 3 (weak), and 93 (25%) EL 4 (lowest). New or updated topics in this CPG include: clarification of the diagnosis of osteoporosis, stratification of the patient according to high-risk and very-high-risk features, a new dual-action therapy option, and transitions from therapeutic options. Conclusion: This guideline is a practical tool for endocrinologists, physicians in general, regulatory bodies, health-related organizations, and interested laypersons regarding the diagnosis, evaluation, and treatment of post-menopausal osteoporosis. Abbreviations: 25(OH)D = 25-hydroxyvitamin D; AACE = American Association of Clinical Endocrinologists; ACE = American College of Endocrinology; AFF = atypical femoral fracture; ASBMR = American Society for Bone and Mineral Research; BEL = best evidence level; BMD = bone mineral density; BTM = bone turnover marker; CI = confidence interval; CPG = clinical practice guideline; CTX = C-terminal telopeptide type-I collagen; DXA = dual-energy X-ray absorptiometry; EL = evidence level; FDA = U.S. Food and Drug Administration; FRAX® = Fracture Risk Assessment Tool; GI = gastrointestinal; HORIZON = Health Outcomes and Reduced Incidence with Zoledronic acid ONce yearly Pivotal Fracture Trial (zoledronic acid and zoledronate are equivalent terms); ISCD = International Society for Clinical Densitometry; IU = international units; IV = intravenous; LSC = least significant change; NOF = National Osteoporosis Foundation; ONJ = osteonecrosis of the jaw; PINP = serum amino-terminal propeptide of type-I collagen; PTH = parathyroid hormone; R = recommendation; ROI = region of interest; RR = relative risk; SD = standard deviation; TBS = trabecular bone score; VFA = vertebral fracture assessment; WHO = World Health Organization.

Effect of echinalkamide identified from Echinacea purpurea (L.) Moench on the inhibition of osteoclastogenesis and bone resorption

Plant cell cultures have been exploited to provide stable production and new secondary metabolites for better pharmacological activity. Fractionation of adventitious root cultures of Echinacea purpurea resulted in the isolation of eleven constituents, including three new compounds. The structures of the three new compounds were determined to be an alkylamide (1), a polyacetylene (2) and a lignan (3) on the basis of combined spectroscopic analysis. To discover new types of antiresorptive agents, we screened for new compounds that regulate osteoclast differentiation, and survival. Among three new compounds, echinalkamide (compound 1) had considerably inhibitory effects on RANKL-induced osteoclast differentiation, and on proliferation of osteoclasts and efficiently attenuated osteoclastic bone resorption without toxicity. In addition, echinalamide treatment inhibited the osteoclast—specific gene expression level. Echinalkamide achieved this inhibitory effect by disturbing phosphorylation of MAPK and activation of osteoclast transcription factors c-Fos and NFATc1. Conclusionally, our study investigated that echinalkamide remarkably inhibited osteoclast differentiation and osteoclast specific gene expression through repression of the MAPK–c-Fos–NFATC1 cascade.

Using negative control outcomes to assess the comparability of treatment groups among women with osteoporosis in the United States

PURPOSE

In contrast to randomized clinical trials, comparative safety and effectiveness assessments of osteoporosis medications in clinical practice may be subject to confounding by indication. We used negative control outcomes to detect residual confounding when comparing osteoporosis medications.

METHODS

Using MarketScan Commercial and Supplemental claims, we identified women aged ≥55 years who initiated an oral bisphosphonate (BP) (risedronate, alendronate, or ibandronate), denosumab (an injected biologic), or intravenous zoledronic acid (ZA) from October 1, 2010 to September 30, 2015. Women with Paget's disease or cancer were excluded. We compared individual oral BPs to each other, denosumab to ZA, denosumab to oral BPs, and ZA to oral BPs, with respect to 11 negative control outcomes identified by subject matter experts. We estimated the 12-month cumulative risk difference (RD) using inverse probability of treatment and censoring weights.

RESULTS

Among 148 587 women, most initiated alendronate (57%), followed by ibandronate (12%), ZA (11%), risedronate (10%), and denosumab (10%). Compared with denosumab, patients initiating ZA had similar risks of all negative control outcomes. Compared with oral BPs, patients initiating denosumab had a higher risk of a wellness visit (RD = 1.2%, 95% CI: 0.4, 1.9) and a lower risk of receiving herpes zoster vaccine (RD = -0.6%, 95% CI: -1.1, -0.2). Comparing ZA with oral BP initiators resulted in two outcomes with positive associations.

CONCLUSIONS

Caution is warranted when comparing injectable vs oral osteoporosis medications, given the potential for unmeasured confounding. Evaluating negative control outcomes could be a standard validity check prior to conducting comparative studies.

Autophagy: A Promising Target for Age-related Osteoporosis

Autophagy is a process the primary role of which is to clear up damaged cellular components such as long-lived proteins and organelles, thus participating in the conservation of different cells. Osteoporosis associated with aging is characterized by consistent changes in bone metabolism with suppression of bone formation as well as increased bone resorption. In advanced age, not only bone mass but also bone strength decrease in both sexes, resulting in an increased incidence of fractures. Clinical and animal experiments reveal that age-related bone loss is associated with many factors such as accumulation of autophagy, increased levels of reactive oxygen species, sex hormone deficiency, and high levels of endogenous glucocorticoids. Available basic and clinical studies indicate that age-associated factors can regulate autophagy. Those factors play important roles in bone remodeling and contribute to decreased bone mass and bone strength with aging. In this review, we summarize the mechanisms involved in bone metabolism related to aging and autophagy, supplying a theory for therapeutic targets to rescue bone mass and bone strength in older people.

Pilose antler aqueous extract promotes the proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells by stimulating the BMP-2/Smad1, 5/Runx2 signaling pathway

Peptides from Pilose antler aqueous extract (PAAE) have been shown to stimulate the proliferation and differentiation of bone marrow mesenchymal stem cells (BMSCs). However, the underlying molecular mechanisms are not well understood. Here, PAAE was isolated and purified to explore the molecular mechanisms underlying PAAE's effects on BMSCs as well as its osteoprotective effects in ovariectomized rats. Our results showed that PAAE promoted proliferation and differentiation of BMSCs to become osteoblasts by enhancing ALP activity and increasing extracellular matrix mineralization. The trabecular microarchitecture of ovariectomized rats was also found to be protected by PAAE. Quantitative reverse transcription-polymerase chain reaction (Quantitative RT-PCR) results suggest that PAAE also increased the expression of osteogenic markers including, alkaline phosphatase (ALP), runt-related transcription factor 2 (Runx2), osteocalcin (OCN), bone morphogenetic protein-2 (BMP-2), and collagen I (COL-I). Immunoblotting results indicated that PAAE upregulated the levels of BMP-2 and Runx2 and was associated with Smad1/5 phosphorylation. PAAE A at the concentration of 200 μg·mL^-1 showed the strongest effect on proliferation and osteogenic differentiation of BMSCs after 48 h. Using matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS), we identified the molecular weight of PAAE A and found that it is less than 3000 Da and showed several significant peaks. In conclusion, PAAE activates the BMP-2/Smad1, 5/Runx2 pathway to induce osteoblastic differentiation and mineralization in BMSCs and can inhibit OVX-induced bone loss. These mechanisms are likely responsible for its therapeutic effect on postmenopausal osteoporosis.

A Mouse Model for Skeletal Structure and Function Changes Caused by Radiation Therapy and Estrogen Deficiency

Radiation therapy and estrogen deficiency can damage healthy bone and lead to an increased fracture risk. The goal of this study is to develop a mouse model for radiation therapy using a fractionated biologically equivalent dose for cervical cancer treatment in both pre- and postmenopausal women. Thirty-two female C57BL/6 mice 13 weeks of age were divided into four groups: Sham + non-irradiated (SHAM + NR), Sham + irradiated (SHAM + IRR), ovariectomy + non-irradiated (OVX + NR) and ovariectomy + irradiated (OVX + IRR). The irradiated mice received a 6 Gy dose of X-rays to the hindlimbs at Day 2, Day 4 and Day 7 (18 Gy total). Tissues were collected at Day 35. DEXA, microCT analysis and FEA were used to quantify structural and functional changes at the proximal tibia, midshaft femur, proximal femur and L1 vertebra. There was a significant (p < 0.05) decline in proximal tibia trabecular BV/TV from (1) IRR compared to NR mice within Sham (- 46%) and OVX (- 41%); (2) OVX versus Sham within NR mice (- 36%) and IRR mice (- 30%). With homogenous material properties applied to the proximal tibia mesh using FEA, there was (1) an increase in whole bone (trabecular + cortical) structural stiffness from IRR compared to NR mice within Sham (+ 10%) and OVX (+ 15%); (2) a decrease in stiffness from OVX versus Sham within NR mice (- 18%) and IRR mice (- 14%). Fractionated irradiation and ovariectomy both had a negative effect on skeletal microarchitecture. Ovariectomy had a systemic effect, while skeletal radiation damage was largely specific to trabecular bone within the X-ray field.

Therapeutic Effects of Low-Intensity Pulsed Ultrasound on Osteoporosis in Ovariectomized Rats: Intensity-Dependent Study

This study investigated the effects of low-intensity pulsed ultrasound (LIPUS) of different spatial-average-temporal-average intensity (I_SATA) ranging from 15-150 mW/cm² on the treatment of osteoporosis in ovariectomized rats. Healthy 3-mo-old female Sprague-Dawley rats were randomly divided into nine groups (n = 12 per group): sham-ovariectomy (OVX) control group, OVX control group and OVX groups treated with LIPUS at seven different intensities (I_SATA: 15, 30, 50, 75, 100, 125 and 150 mW/cm², respectively). LIPUS was applied to bilateral femurs 12 wk post-OVX for 20 min/d for 6 wk. Micro-computed tomography, biomechanical tests, serum biochemical analysis and grip strength tests were performed to evaluate the therapeutic effects of LIPUS at different intensities. Results revealed that LIPUS intensity yielded strong correlations with bone mineral density and bone microstructure (R² = 0.57-0.83) and bone mechanical strength (R² = 0.80-0.97), and that the intensity of 150 mW/cm², instead of the 30 mW/cm² widely used in bone fracture healing, was most effective in maintaining bone mass among all the LIPUS signals between 15 and 150 mW/cm². This suggests that higher ultrasound intensity (i.e., 150 mW/cm²) may be more effective than lower intensity in mitigation of osteopenia and osteoporosis.

A Primary Care Provider's Guide to Bone Health in Spinal Cord-Related Paralysis

Individuals with spinal cord injury/disorder (SCI/D) are at high risk for developing secondary osteoporosis. Bone loss after neurologic injury is multifactorial and is dependent on the time from and extent of neurologic injury. Most bone loss occurs in the first year after complete motor paralysis, and fractures occur most commonly in the distal femur and proximal tibia (paraplegic fracture). The 2019 International Society for Clinical Densitometry Position Statement in SCI establishes that dual-energy X-ray absorptiometry (DXA) can be used to both diagnose osteoporosis and predict lower extremity fracture risk in individuals with SCI/D. Pharmacologic treatments used in primary osteoporosis have mixed results when used for SCI/D-related osteoporosis. Ambulation, standing, and electrical stimulation may be helpful at increasing bone mineral density (BMD) in individuals with SCI/D but do not necessarily correlate with fracture risk reduction. Clinicians caring for individuals with spinal cord-related paralysis must maintain a high index of suspicion for fragility fractures and consider referral for surgical evaluation and management.

Comparison of skeletal changes related to patients with chronic kidney disease and healthy individuals in digital panoramic radiography

Background

Chronic kidney disease (CKD) is a prevalent condition affecting bone metabolism. Bone changes in CKD patients also known as renal osteodystrophy happen due to disorders in the regulation of water and electrolytes caused by the disease. The aim of this study is to investigate the bone changes of CKD stages 3-5 patients without dialysis using digital panoramic radiography.

Materials and Methods

In this cross-sectional study, panoramic radiographs were obtained from 30 patients with CKD stages 3-5 and 30 age and gender matched healthy individuals. The mean values of quantitative parameters such as mental index (MI), panoramic mandibular index (PMI), and antegonial index (AI) were measured and qualitative parameters such as mandibular cortical index (MCI) and trabecular bone pattern (TP) were recorded based on Kelemetti and Lindh calcifications, respectively. Statistical analysis was performed using t-test, Chi-square, and Mann-Whitney test (α = 0.05).

Results

The mean values of MI, PMI, and AI in the two groups were not statistically significant (P > 0.05). MCI and TP were significantly different between the two groups. MCI showed more defects in mandibular cortex of CKD patients (6.7% of patients vs. 0% of control group were C₃, P = 0.038), and TP showed more porosity in mandibular bone of CKD patients (10% of patients vs. 0% of control group were sparse, P = 0.001).

Conclusion

The amount of MI, PMI, and AI were not related to CKD. While MCI and TP were significant parameters that showed mandibular cortical situation and trabecular bone pattern, they assess osteoporosis level in a more reliable manner in CKD stages 3-5 patients without dialysis.

The Effectiveness and Safety of Acupoint Catgut Embedding for the Treatment of Postmenopausal Osteoporosis: A Systematic Review and Meta-Analysis

Purpose

To evaluate the effectiveness and safety of acupoint catgut embedding therapy (ACET) in postmenopausal osteoporosis (PMOP).

Methods

Review of some databases from their inception to June 2018 and randomized controlled trials (RCTs) in which ACET with PMOP were included. Two researchers extracted and evaluated the information independently. Cochrane Collaboration's tool and Jadad scale were used to evaluate the quality of the studies. RevMan V.5.3.3 software was used to carry out the meta-analysis while trial sequential analysis (TSA) performed with TSA 0.9 software.

Results

12 RCTs with 876 participants were included in this review. Meta-analysis showed that ACET alone was not superior to medication in effectiveness rate (RR= 1.11; 95% CI (0.89, 1.40); P=0.35) and E2 (SMD= 0.20; 95% CI (-0.17, 0.57); P=0.28; I ² =20%) while ACET combining medication was more effective on the effectiveness rate (RR= 1.32; 95% CI (1.20, 1.46); P<0.000 01) and E2 (SMD= 1.24; 95% CI (0.63, 1.84); P<0.0001). Additionally, ACET combining calcium could increase the bone mineral density (BMD) of the L2~4 vertebrae and femur-neck [WMD_L2~4 = 0.03; 95% CI (0.01, 0.05); P=0.003; and WMD_Femur-neck = 0.07; 95% CI (0.03, 0.10); P = 0.0006], reduce TCM syndrome score [WMD = -1.85; 95% CI (-2.13, -1.57); P<0.000 01], improve patient's quality of life [WMD_{three  months} = 6.90; 95% CI (3.90, 9.89); P<0.000 01; and WMD_{six  months} = 12.34; 95% CI (5.09, 19.60); P=0.0009], and relieve pain [WMD_VAS = -1.26; 95% CI (-1.66, -0.85); P<0.000 01; and WMD_{Pain  score} = -2.59; 95% CI (-4.76, -0.43); P= 0.02]. The TSA showed that the effectiveness of ACET for PMOP was demonstrated accurately.

Conclusions

ACET combining medication but not ACET alone is more effective than medication as comparison in the treatment of PMOP. As a novel treatment, ACET shows the potential of effectiveness and deserves further high quality of well-designed study.

Chrysosplenetin promotes osteoblastogenesis of bone marrow stromal cells via Wnt/β-catenin pathway and enhances osteogenesis in estrogen deficiency-induced bone loss

BACKGROUND

Chrysosplenetin is an O-methylated flavonol compound isolated from the plant Chamomilla recutita and Laggera pterodonta. The aim of our research is to evaluate the function of Chrysosplenetin on osteogenesis of human-derived bone marrow stromal cells (hBMSCs) and inhibition of estrogen deficiency-induced osteoporosis via the Wnt/β-catenin signaling pathway.

METHOD

hBMSCs are cultured and treated by Chrysosplenetin in the absence or presence of Wnt inhibitor dickkopf-related protein 1 (DKK1) or bone morphogenetic protein 2 (BMP2) antagonist Noggin. RT-qPCR is taken to identify the genetic expression of target genes of Wnt/β-catenin pathway and osteoblast-specific markers. The situation of β-catenin is measured by western blot and immunofluorescence staining. An ovariectomized (OVX) mouse model is set up to detect the bone loss suppression by injecting Chrysosplenetin. Micro-CT and histological assay are performed to evaluate the protection of bone matrix and osteoblast number. Serum markers related with osteogenesis are detected by ELISA.

RESULTS

In the present study, it is found that Chrysosplenetin time-dependently promoted proliferation and osteoblastogenesis of hBMSCs reaching its maximal effects at a concentration of 10 μM. The expressions of target genes of Wnt/β-catenin pathway and osteoblast-specific marker genes are enhanced by Chrysosplenetin treatment. Furthermore, the phosphorylation of β-catenin is decreased, and nuclear translocation of β-catenin is promoted by Chrysosplenetin. Osteogenesis effects mentioned above are founded to be blocked by DKK1 or BMP2 antagonist Noggin. In vivo study reveals that Chrysosplenetin prevents estrogen deficiency-induced bone loss in OVX mice detected by Micro-CT, histological analysis, and ELISA.

CONCLUSIONS

Our study demonstrates that Chrysosplenetin improves osteoblastogenesis of hBMSCs and osteogenesis in estrogen deficiency-induced bone loss by regulating Wnt/β-catenin pathway.

Bench-to-bedside strategies for osteoporotic fracture: From osteoimmunology to mechanosensation

Osteoporosis is characterized by a decrease in bone mass and strength, rendering people prone to osteoporotic fractures caused by low-energy forces. The primary treatment strategy for osteoporotic fractures is surgery; however, the compromised and comminuted bones in osteoporotic fracture sites are not conducive to optimum reduction and rigid fixation. In addition, these patients always exhibit accompanying aging-related disorders, including high inflammatory status, decreased mechanical loading and abnormal skeletal metabolism, which are disadvantages for fracture healing around sites that have undergone orthopedic procedures. Since the incidence of osteoporosis is expected to increase worldwide, orthopedic surgeons should pay more attention to comprehensive strategies for improving the poor prognosis of osteoporotic fractures. Herein, we highlight the molecular basis of osteoimmunology and bone mechanosensation in different healing phases of elderly osteoporotic fractures, guiding perioperative management to alleviate the unfavorable effects of insufficient mechanical loading, high inflammatory levels and pathogen infection. The well-informed pharmacologic and surgical intervention, including treatment with anti-inflammatory drugs and sufficient application of antibiotics, as well as bench-to-bedside strategies for bone augmentation and hardware selection, should be made according to a comprehensive understanding of bone biomechanical properties in addition to the remodeling status of osteoporotic bones, which is necessary for creating proper biological and mechanical environments for bone union and remodeling. Multidisciplinary collaboration will facilitate the improvement of overall osteoporotic care and reduction of secondary fracture incidence.

MiR-320a was highly expressed in postmenopausal osteoporosis and acts as a negative regulator in MC3T3E1 cells by reducing MAP9 and inhibiting PI3K/AKT signaling pathway

BACKGROUND

Postmenopausal osteoporosis (PMO), as a frequent disease in postmenopausal women, is mainly caused by the lack of estrogen. MiR-320a has been found to abate osteoblast function and induce oxidative stress before osteoporosis. However, studies on the downstream target gene and related signaling pathway of miR-320a in PMO are still obscure. This study aims to deal with these problems.

METHODS

The expression levels of miR-320a and microtubule-associated protein 9 (MAP9) in patients with osteoporosis were analyzed on the basis of the GEO database. The cells viability was determined by methylthiazolyl tetrazolium bromide (MTT). Flow cytometry and western blot were used to detect the cells apoptosis and the expression of apoptosis-related proteins, respectively. The cells differentiation-related proteins were detected by qRT-PCR and western blot. The interaction between miR-320a and MAP9 was predicted by biological software and verified by dual luciferase reporter assay and rescue assay. The expression levels of PI3K, p-PI3K, AKT and p-AKT in MC3T3-E1 cells were assessed by western blot.

RESULTS

We observed that miR-320a was over-expressed in PMO patients and exhibited inhibitory effects on MC3T3-E1 cells activity and differentiation, as well as promoting effects on MC3T3-E1 cells apoptosis. MAP9 was verified as a target gene of miR-320a and was negatively regulated by miR-320a. Based on the GEO database, MAP9 was found to be lower expressed in PMO patients. Rescue assay demonstrated that down-regulation of MAP9 could alleviate the promoting effects of miR-320a inhibitor on MC3T3-E1 cells activity and differentiation and the inhibitory effects of miR-320a inhibitor on MC3T3-E1 cells apoptosis. Mechanically, miR-320a/MAP9 possibly took part in MC3T3-E1 cells viability, differentiation and apoptosis via mediating PI3K/AKT signaling pathway.

CONCLUSIONS

Our outcomes demonstrated that miR-320a promoted MC3T3-E1 cells apoptosis, suppressed MC3T3-E1 cells viability and differentiation through targeting MAP9 and modulating PI3K/AKT signaling pathway, which provided theoretical support for miR-320a/MAP9 as promising targets for the treatment and prevention of PMO.

The Neuropeptide Vasoactive Intestinal Peptide Levels in Serum are Inversely Related to Disease Severity of Postmenopausal Osteoporosis: A Cross-Sectional Study

Background: The neuropeptide vasoactive intestinal peptide (VIP) has been identified as inhibiting osteoclastogenesis and suppressing inflammation. Objective: This study was conducted to examine serum VIP levels in postmenopausal osteoporosis (PMOP) patients and explore the correlation of serum VIP levels with disease severity of PMOP. Methods: A total of 106 postmenopausal women diagnosed as osteoporotic were enrolled in the study and 102 postmenopausal women with normal bone mineral density (BMD) were enrolled as controls. BMD at the femoral neck (FN), lumbar spine 1-4, and total hip were examined using dual-energy X-ray absorptiometry. Genant semiquantitative grading was used for vertebral morphometry and fracture. Serum VIP levels were tested using enzyme-linked immunosorbent assay. Serum inflammatory factor interleukin-1β (IL-1β), osteoclastic activity marker tartrate-resistant acid phosphatase 5b (TRACP-5b), and estrogen-2 (E2) were also examined. Receiver operating characteristic (ROC) analyses was performed to determine the diagnostic values of serum VIP, IL-1β, TRCAP-5, and E2 with regard to Genant grade. Results: Our findings demonstrated a reduction in the serum level of VIP expressed in PMOP patients compared with controls. In the PMOP group, patients with lumbar fracture had significantly lower serum VIP concentrations in comparison with healthy controls. Serum VIP concentrations were positively associated with BMD at the FN, lumbar spine 1-4, and total hip. We also observed that serum VIP levels were positively correlated with E2 levels but negatively correlated with IL-1β and TRCAP-5 levels. In addition, ROC analysis found that reduction of serum VIP in combination with elevation of TRACP-5b may serve as an indicator of a severe Genant grade. Conclusions: Attenuated serum VIP levels were linked to disease severity of PMOP and may act as a protective marker for PMOP.

Comprehensive circular RNA profiling reveals circ_0002060 as a potential diagnostic biomarkers for osteoporosis

Osteoporosis (OP) is a multifactorial and common bone disease worldwide. The clinical diagnosis and treatment of osteoporosis has limitations since changes in bone density occur slightly. Thus, it is critically needed to look for new biomarkers to identify and cure osteoporosis. CircRNAs are important molecular regulators that participate in various biological processes and present tremendous therapeutic potential. The role of circRNAs in osteoporosis remains largely unknown. Here, we explore the expression of circRNAs in osteoporosis using microarray analysis, and identify potential circRNAs associated with osteoporosis by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) validation and statistical analysis in clinical samples. As a result, circ_0006873 and circ_0002060 were found to be significantly upregulated between nonosteoporotic controls and osteoporosis patients (n = 40, respectively). Pearson correlation analysis showed that the level of circ_0006873 and circ_0002060 were associated with the low-bone mineral density in patients with osteoporosis. Furthermore, ROC analysis indicated that circ_0002060 showed potential diagnostic value for osteoporosis. Taken together results using bioinformatics, experimental analysis, and disease models, we revealed that circ_0002060 could be used as potential diagnostic biomarker and therapeutic target in osteoporosis.

ClC-3 chloride channels are involved in estradiol regulation of bone formation by MC3T3-E1 osteoblasts

Evidence has been reported by us and others supporting the important roles of chloride channels in a number of osteoblast cell functions. The ClC-3 chloride channel is activated by estradiol binding to estrogen receptor alpha on the cell membranes of osteoblasts. However, the functions of these chloride channels in estrogen regulation of osteoblast metabolism remain unclear. In the present study, the roles of chloride channels in estrogen regulation of osteoblasts were investigated in the osteoblastic cell line MC3T3-E1. Estrogen 17β-estradiol enhanced collagen I protein expression, alkaline phosphatase activity, and mineralization were inhibited, by chloride channel blockers. Estradiol promoted ClC-3 chloride channel protein expression. Silencing of ClC-3 chloride channel expression prevented the elevation of osteodifferentiation in osteoblasts, which were regulated by estrogen. These data suggest that estrogen can regulate bone formation by activating ClC-3 chloride channels and the activation of ClC-3 chloride channels can enhance the osteodifferentiation in osteoblasts.

Magnetic resonance imaging T1 and T2 mapping provide complementary information on the bone mineral density regarding cancellous bone strength in the femoral head of postmenopausal women with osteoarthritis

BACKGROUND

Since bone mass is not the only determinant of bone strength, there has been increasing interest in incorporating the bone quality into fracture risk assessments. We aimed to examine whether the magnetic resonance imaging (MRI) T1 or T2 mapping value could provide information that is complementary to bone mineral density for more accurate prediction of cancellous bone strength.

METHODS

Four postmenopausal women with hip osteoarthritis underwent 3.0-T MRI to acquire the T1 and T2 values of the cancellous bone of the femoral head before total hip arthroplasty. After the surgery, the excised femoral head was portioned into multiple cubic cancellous bone specimens with side of 5 mm, and the specimens were then subjected to microcomputed tomography followed by biomechanical testing.

FINDINGS

The T1 value positively correlated with the yield stress (σ_y) and collapsed stress (σ_c). The T2 value did not correlate with the yield stress, but it correlated with the collapsed stress and strength reduction ratio (σ_c/σ_y), which reflects the progressive re-fracture risk. Partial correlation coefficient analyses, after adjusting for the bone mineral density, showed a statistically significant correlation between T1 value and yield stress. The use of multiple coefficients of determination by least squares analysis emphasizes the superiority of combining the bone mineral density and the MRI mapping values in predicting the cancellous bone strength compared with the bone mineral density-based prediction alone.

INTERPRETATION

The MRI T1 and T2 values predict cancellous bone strength including the change in bone quality.

Vitamin K2 stimulates MC3T3‑E1 osteoblast differentiation and mineralization through autophagy induction

Vitamin K2 likely exerts its protective effects during osteoporosis by promoting osteoblast differentiation and mineralization. However, the precise mechanism remains to be fully elucidated. Autophagy maintains cell homeostasis by breaking down and eliminating damaged proteins and organelles. Increasing evidence in recent years has implicated autophagy in the development of osteoporosis. The aim of the present study was to verify whether vitamin K2 (VK2) can induce autophagy during the differentiation and mineralization of osteoblasts. In the present study, MC3T3-E1 osteoblasts were treated with various doses of VK2 (10⁻⁸−10⁻³ M) for 1–5 days. The results revealed no cytotoxicity at concentrations below 10⁻⁵ M, but cell viability was reduced in a dose-dependent manner at concentrations above 10⁻⁵ M. Furthermore, MC3T3-E1 osteoblasts were seeded in 6-well plates in complete medium supplemented with dexamethasone, β-glycerophosphate and vitamin C (VC) for osteogenic differentiation. MC3T3-E1 osteoblasts treated with different concentrations (10⁻⁵, 10⁻⁶ and 10⁻⁷ M) of VK2 for 24 h on days 1, 3, 5 and 7 of the differentiation protocol. It was confirmed that VK2 promoted osteoblast differentiation and mineralization by using alkaline phosphatase (ALP) and alizarin red staining. Using western blotting, immunofluorescence, monodansylcadaverine staining and reverse transcription-quantitative polymerase chain reaction, it was observed that VK2 induced autophagy in osteoblasts. The results revealed that VK2 (1 µM) significantly increased ALP activity and the conversion of microtubule associated protein 1 light chain 3-α (LC3)II to LC3I in MC3T3-E1 osteoblasts (P<0.05) at every time point. The number of fluorescent bodies and the intensity increased with VK2, and decreased following treatment with 3-MA+VK2. There was an increase in the mRNA expression levels of ALP, osteocalcin (OCN) and Runt-related transcription factor 2 in VK2-treated cells (P<0.01). The present study further confirmed the association between autophagy and osteoblast differentiation and mineralization through treatment with an autophagy inhibitor [3-methyladenine (3-MA)]. Osteoblasts treated with 3-MA exhibited significant inhibition of ALP activity and osteogenic differentiation (both P<0.05). In addition, ALP activity and osteogenesis in the VK2+3-MA group was lower compared with VK2-treated cells (P<0.05 for both). The present study confirmed that VK2 stimulated autophagy in MC3T3 cells to promote differentiation and mineralization, which may be a potential therapeutic target for osteoporosis.

Advance on Resveratrol Application in Bone Regeneration: Progress and Perspectives for Use in Oral and Maxillofacial Surgery

The natural polyphenol Resveratrol (RSV) claims numerous positive effects on health due to the well documented biological effects demonstrating its potential as a disease-preventing agent and as adjuvant for treatment of a wide variety of chronic diseases. Since several studies, both in vitro and in vivo, have highlighted the protective bone aptitude of RSV both as promoter of osteoblasts' proliferation and antagonist of osteoclasts' differentiation, they could be interesting in view of applications in the field of dentistry and maxillofacial surgery. This review has brought together experimental findings on the use of RSV in the regeneration of bone tissue comprising also its application associated with scaffolds and non-transfusional hemocomponents.

Influence of Thyroid-stimulating Hormone Suppression Therapy on Bone Mineral Density in Patients with Differentiated Thyroid Cancer: A Meta-analysis

Background

The effects of subclinical hyperthyroidism on bone mineral density (BMD) induced by thyroid-stimulating hormone (TSH) suppression therapy in patients with differentiated thyroid cancer (DTC) remains unclear. We conducted a meta-analysis to determine the influence of TSH suppression therapy on BMD.

Methods

We performed a systematic search to identify studies which included BMD measurement of femoral neck, total hip or lumbar spine in patients on TSH suppression therapy for DTC. Main outcome measures were difference of BMD of femoral neck, total hip or lumbar spine measured by dual energy X-ray absorptiometry between patients and controls.

Results

A systematic search yielded a total of 11 published controlled cross-sectional studies (including about 571 patients and 836 controls). TSH suppression therapy was associated with the lower BMD of total hip (weighted mean difference [WMD], -0.023; 95% confidence interval [CI], -0.047 to 0.000; P=0.050) and spine (WMD, -0.041; 95% CI, -0.057 to -0.026; P<0.001) in postmenopausal women with DTC, while it was not associated with that in premenopausal women and men with DTC.

Conclusions

Although the included studies were limited by small numbers, results suggested possible association between chronic TSH suppression therapy and the lower BMD of spine and total hip in postmenopausal women (but not in premenopausal women and men) with DTC. A large, well-designed study with long-term follow-up would provide further insight into the influence of TSH suppression therapy and loss of BMD.

Combined Extracts of Herba Epimedii and Fructus Ligustri Lucidi Rebalance Bone Remodeling in Ovariectomized Rats

This study aimed to investigate the osteoprotective effect and the possible molecular mechanisms of the combined extracts of Herba Epimedii and Fructus Ligustri Lucidi on postmenopausal osteoporosis (PMOP). Forty-eight female SD rats were sham-operated (Sham, n = 8) or ovariectomized (OVX, n = 40). Then after a week, OVX rats were divided randomly into five groups (n = 8 in each group): OVX, extracts of Herba Epimedii (HE, 0.35 g/kg), extracts of Fructus Ligustri Lucidi (FLL, 0.35 g/kg), combined extracts of HE and FLL (HE & FLL, 0.20 g/kg HE plus 0.15 g/kg FLL), and Raloxifene hydrochloride (RH, 6.25 mg/kg) groups. All groups were administered once daily for 12 weeks. Indicators related to bone remodeling were detected, including estradiol (E₂), bone mineral density (BMD), maximal load, ultimate deflection, micro-CT properties, tartrate-resistant acid phosphatase (TRACP) and alkaline phosphatase (ALP) levels in serum and bone, and the protein and mRNA expression of bone turnover markers (RANKL, M-CSF, Wnt5a, Atp6v0d2, OPG, IGF-1, TGF-β1, and Bmp-2). Results showed that the combined extracts could increase serum E₂ levels and BMD, enhance bone strength, reserve bone microstructure degeneration, promote bone formation, and inhibit bone resorption through upregulating the mRNA and protein expression of OPG, IGF-1, TGF-β1, and Bmp-2, while downregulating RANKL, M-CSF, Wnt5a, and Atp6v0d2. These findings demonstrated that the combined extracts of Herba Epimedii and Fructus Ligustri Lucidi with bone protective effects on OVX rats might be an alternative medicine for the treatment of PMOP.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS AND AMERICAN COLLEGE OF ENDOCRINOLOGY CLINICAL PRACTICE GUIDELINES FOR THE DIAGNOSIS AND TREATMENT OF POSTMENOPAUSAL OSTEOPOROSIS - 2016

ABBREVIATIONS

AACE = American Association of Clinical Endocrinologists AFF = atypical femur fracture ASBMR = American Society for Bone and Mineral Research BEL = best evidence level BMD = bone mineral density BTM = bone turnover marker CBC = complete blood count CI = confidence interval DXA = dual-energy X-ray absorptiometry EL = evidence level FDA = U.S. Food and Drug Administration FLEX = Fracture Intervention Trial (FIT) Long-term Extension FRAX_® = Fracture Risk Assessment Tool GFR = glomerular filtration rate GI = gastrointestinal HORIZON = Health Outcomes and Reduced Incidence with Zoledronic Acid Once Yearly IOF = International Osteoporosis Foundation ISCD = International Society for Clinical Densitometry IU = international units IV = intravenous LSC = least significant change NBHA = National Bone Health Alliance NOF = National Osteoporosis Foundation 25(OH)D = 25-hydroxy vitamin D ONJ = osteonecrosis of the jaw PINP = serum carboxy-terminal propeptide of type I collagen PTH = parathyroid hormone R = recommendation RANK = receptor activator of nuclear factor kappa-B RANKL = receptor activator of nuclear factor kappa-B ligand RCT = randomized controlled trial RR = relative risk S-CTX = serum C-terminal telopeptide SQ = subcutaneous VFA = vertebral fracture assessment WHO = World Health Organization.

Elevated serum CCL4/MIP-1β levels in postmenopausal osteoporosis patients are linked with disease severity

AIM

To investigate if the serum CC motif ligand 4 (CCL4) levels are linked to disease severity in patients with postmenopausal osteoporosis (PMOP).

PATIENTS & METHODS

We enrolled 66 PMOP females, 68 postmenopausal nonosteoporotic women and 67 healthy women of childbearing age. Bone mineral densities were assessed with dual x-ray absorptiometry scans. The Oswestry disability index and the visual analog scale were employed to quantify functional ability and severity of symptoms. Serum CCL4 levels were examined with a quantitative sandwich enzyme-linked immunosorbent assay.

RESULTS

We observed a significant negative correlation of CCL4 serum levels with bone mineral density. Furthermore, serum CCL4 concentrations were significantly related to the visual analog scale and Oswestry Disability Index scores.

CONCLUSION

Serum CCL4 is a potential biomarker to evaluate disease severity in PMOP females.

Effect of Childbirth Age on Bone Mineral Density in Postmenopausal Women

BACKGROUND

In postmenopausal women, there is rapid bone loss due to estrogen depletion. In women, reproductive factors such as age at menarche, breastfeeding, and parity are considered risk factors of osteoporosis. Many reports suggest that obesity is associated with a reduced risk of osteoporosis. This nationwide, population-based study aims to identify the association between maternal age and osteoporosis risk in postmenopausal women of different obesity classifications.

METHODS

We assessed data from the Korean National Health and Nutrition Examination Survey 2010-2012. The study included 1,328 postmenopausal women, after excluding women with missing data for reproductive history among 4,546 postmenopausal women in the survey. Multivariate regression was used to identify the association between childbirth age and postmenopausal bone mineral density after adjustments for confounding factors.

RESULTS

The prevalence of postmenopausal osteoporosis was 35.24% (n = 468). After dividing the subjects into obese and non-obese groups based on body mass index (BMI) and waist circumference, there were significant differences between non-osteoporosis and osteoporosis groups with regard to age at first childbirth, age at last childbirth, and parity in the BMI-based general obesity group. The prevalence of osteoporosis was highest in women older than 35 years old at last childbirth. The prevalence of osteoporosis was also greater in women with parity ≥ 4 compared to those with lower parity levels.

CONCLUSION

Postmenopausal women of older age at last childbirth and higher parity were at increased risk of osteoporosis in the BMI-based non-general obesity group.

Icariin protects against iron overload-induced bone loss via suppressing oxidative stress

Iron overload is common in patients with diseases such as hemoglobinopathies, hereditary hemochromatosis or elderly men and postmenopausal women. This disorder is frequently associated with bone loss and recently has been considered as an independent risk factor for osteoporosis. By excess reactive oxygen species (ROS) production through Fenton reaction, iron could induce osteoblast apoptosis, inhibit osteoblast osteogenic differentiation. Moreover, Iron could also promote osteoclasts differentiation and bone absorption. The goal of the study is to investigate whether icariin could reverse iron overload-induced bone loss in vitro and in vivo. Icariin is the major active ingredient of Herba Epimedii and has antioxidant, antiosteoporosis functions. In the current study, we demonstrated that oral administration of icariin significantly prevented bone loss in iron overloaded mice. Icariin could protect against iron overload-induced mitochondrial membrane potential dysfunction and ROS production, promote osteoblast survival and reverse the reduction of Runx2, alkaline phosphatase, and osteopontin expression induced by iron overload. Icariin also inhibited osteoclasts differentiation and function. Moreover, we also found that icariin remarkably reduced iron accumulation in bone marrow, suggesting that icariin has the ability to regulate systemic iron metabolism in vivo. These results indicated that icariin could be a potential natural resource for developing medicines to prevent or treat iron overload-induced osteoporosis.

Decreasing trend of bone mineral density in US multiethnic population: analysis of continuous NHANES 2005-2014

Studies examining recent bone mineral density (BMD) trends in the US population are limited. In our study, we found that age-adjusted mean BMD among US men and women was stable from 2005 to 2010, but then declined in 2013-2014. We also explored factors associated with decreasing BMD in recent years.

INTRODUCTION

Osteoporosis prevalence in the USA declined between 1988 and 2006, while the declining trend in hip fracture may have plateaued in 2013-2014. We aimed to examine whether there has been a corresponding change in BMD trajectory for the US population.

METHODS

Continuous National Health and Nutrition Examination Survey (NHANES) data from 2005-2006 to 2013-2014 were analyzed to examine BMD trends among US men and women aged 30 years and older and among different race/ethnicity subgroups. ANOVA and Bonferroni adjustments were used to examine the differences in mean BMD, and multiple linear regressions adjusting for potential confounding effects were employed to examine BMD trends.

RESULTS

After age standardization, the mean BMD of the femur neck for the first three NHANES cycles was stable (all p > 0.1) in both men and women, but significantly decreased in 2013-2014, from 0.864 g/cm2 to 0.846 g/cm2 (p = 0.0025) in men and from 0.789 to 0.771 g/cm2 (p = 0.03) in women. The overall mean femur neck BMD in 2013-2014 was significantly lower than that in earlier survey cycles in both men and women, even after adjusting for multiple covariates, including age, race, physical activity, previous fracture, BMI, and other variables. Similar results were observed in subgroup analyses of race and sensitivity analyses.

CONCLUSIONS

Age-adjusted mean BMD decreased in 2013-2014 in both men and women, and this significant decrease was also observed in sensitivity and subgroup analyses. The decreased BMD in 2013-2014 still remained significant even after being adjusted for multiple potentially confounding effects.

DGCR5 induces osteogenic differentiation by up-regulating Runx2 through miR-30d-5p

BACKGROUND

Postmenopausal osteoporosis (PMOP) is a metabolic bone disease caused by unbalance between osteoblast bone formation and osteoclast bone resorption. In this study, the moderating effect of DGCR5 on osteogenic differentiation and its role in PMOP was assessed.

METHODS

The expression levels of DGCR5, miR-30d-5p, and Runt-related transcription factor 2 (Runx2) mRNA and protein were determined by qRT-PCR and western blot, separately. The bone marrow human mesenchymal stem cells (hMSCs) were isolated from bone marrow of patients with PMOP or the healthy control. ALP activity and bone mineral density (BMD) were detected to reflect the osteogenic differentiation status. RIP and RNA pull-down assay were performed to explore the combination and interaction between DGCR5 and miR-30d-5p.

RESULTS

Compared with the healthy control group (n = 20), DGCR5 was down-regulated in hMSCs from patients with PMOP (n = 20). Overexpression of DGCR5 induced osteogenic differentiation of hMSCs. DGCR5 up-regulated the expression of Runx2 through miR-30d-5p. DGCR5 up-regulated the expression of Runx2 through miR-30d-5p to induce osteogenic differentiation of hMSCs.

CONCLUSION

DGCR5 negatively regulates miR-30d-5p, and it up-regulates Runx2 through miR-30d-5p, thereby inducing osteogenic differentiation of hMSCs, which may help to delay PMOP development.

miRNA-133a-5p Inhibits the Expression of Osteoblast Differentiation-Associated Markers by Targeting the 3' UTR of RUNX2

Recent studies have recognized the involvement of microRNAs (miRNAs) in the development of osteoporosis, which regulate the balance between osteogenesis and osteoclasis. In this study, we investigated the regulation by miRNA-133a-5p on the osteoblast differentiation-associated markers in the mouse osteoblast-like MC3T3-E1 cells by RUNX2. First, we manipulated the miRNA-133a level in the MC3T3-E1 cells with 20 or 40 nM miR-133a-5p mimics, miR-133a-5p inhibitor, or scramble miRNA. Then, we quantified with real-time polymerase chain reaction (qRT-PCR) the expression of Collagen I, osteocalcin (OCN), and osteopontin (OPN) in the miR-133a-5p-manipulated MC3T3-E1 cells. And the confocal microscopy was also utilized to confirm the regulation by miR-133a-5p on the expression of the three molecules. We also investigated the extracellular matrix (ECM) mineralization and the alkaline phosphatase (ALP) activity in the miR-133a-5p-manipulated MC3T3-E1 cells. In addition, we explored the possible targeting by miR-133a-5p on RUNX2, which was a well-recognized promoter to osteoblast differentiation, with luciferase reporter, qRT-PCR, and Western blotting assay. Results demonstrated that the miRNA-133a-5p mimics markedly reduced, whereas the miRNA-133a-5p inhibitor significantly promoted the expression of Collagen I, OCN, and OPN, the ECM mineralization, and the ALP activity in MC3T3-E1 cells. The alignment analysis demonstrated a high homology between miRNA-133a-5p and the 3' UTR of RUNX2. Moreover, the luciferase reporter assay demonstrated that miRNA-133a-5p targeted the 3' UTR of RUNX2, and inhibited the expression of RUNX2 in both mRNA and protein levels. In conclusion, we identified the inhibition by miRNA-133a-5p to the expression of osteoblast differentiation markers, to the ECM mineralization, and to the ALP activity in MC3T3-E1 cells, by targeting the 3' UTR of RUNX2. Our study suggests that miRNA-133a-5p might be an important target to inhibit osteoblast differentiation in osteoporosis.