Utility of DXA screening for diagnosis of osteoporosis in US veterans aged 70 years and older

Long Noncoding RNA P53 Upregulated Regulator of P53 Levels Promotes Osteogenic Differentiation in Osteoporosis Progression Through Sponging miR-135a-5p

This study aimed to explore the expression of long noncoding RNA p53 upregulated regulator of P53 levels (lncRNA PURPL) and microRNA (miR)-135a-5p in osteoporosis and their role in osteogenic differentiation. The relationship between lncRNA PURPL and miR-135a-5p was confirmed by Star-Base and luciferase reporter assay. Quantitative reverse transcription polymerase chain reaction (RT-qPCR) assay was used to detect lncRNA PURPL and miR-135a-5p expression. RT-qPCR and western blot analysis were used to measure osteogenic markers expression. Alkaline phosphatase (ALP) activity was also determined. Results indicated that lncRNA PURPL binds to miR-135a-5p. lncRNA PURPL expression was decreased and miR-135a-5p expression was increased in patients with osteoporosis. In the process of osteogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs), the expression levels of osteoblast markers including RUNX family transcription factor 2 (Runx2), ALP and Osterix, and ALP activity were significantly increased. Besides, lncRNA PURPL was improved, while miR-135a-5p was down-regulated during the osteogenic differentiation of hBMSCs. Moreover, lncRNA PURPL-siRNA significantly decreased the expression of ALP, Runx2 and Osterix, and reduced ALP activity in hBMSCs subjected to osteogenic induction, while all of these effects were reversed by miR-135a-5p inhibitor. In conclusion, lncRNA PURPL/miR-135a-5p may be a new axis for osteoporosis treatment.

Meta-Analysis of Effects of Nutritional Intervention Combined with Calcium Carbonate D3 Tablets on Bone Mineral Density, Bone Metabolism, and Curative Effect in Patients with Osteoporosis

To investigate the changes in bone mineral density, bone metabolism, and efficacy of nutritional intervention combined with calcium carbonate D3 tablets in patients with osteoporosis, a RevMan 5.2 software meta-analysis was conducted in this study. According to the therapeutic direction of nutritional intervention combined with calcium carbonate D3 tablets for osteoporosis patients, relevant literature were searched in Wanfang Medical, CNKI, VIP, and PubMed literature databases at home and abroad. Keywords included bone mineral density, bone metabolism, blood calcium (Ca), blood phosphorus (P), osteocalcin (OC), bone mineral density (BMD), serum alkaline phosphatase (ALP), efficacy, osteoporosis, and nutritional intervention. Literature that met the criteria were deleted, and meta-analysis was performed using RevMan 5.2 software. The results indicate that a total of 10 Chinese literature were included. Compared with the monotherapy group, the clinical efficacy, osteocalcin, BMD, alkaline phosphatase, calcium, and phosphorus were significantly higher in the combination group (P < 0.05). Based on calcium carbonate D3, treatment combined with nutritional intervention can enhance the clinical efficacy, bone metabolism, and bone mineral density of patients with osteoporosis, and nutritional intervention combined with calcium carbonate D3 tablets is a feasible program to promote the recovery of patients with osteoporosis.

Association of bone-related biomarkers with femoral neck bone strength

BACKGROUND

Femoral neck fractures are the worst consequence of osteoporosis (OP), and its early prevention and treatment have become a public health problem. This study aims to investigate the relationship of bone-related biomarkers, femoral neck bone mineral density (BMD) and maximum load (L_max), selecting the indicator which can reflect femoral neck bone loss and reduced bone strength.

METHODS

A total of 108 patients were recruited from January 2017 to December 2019. Venous blood samples were collected from patients before total hip replacement, and femoral neck samples were collected during the surgery. Femoral neck BMD, femoral neck L_max, bone-related markers (serum levels of bone turnover markers, protein expression of type I collagen (COL-I) and osteopontin (OPN) in femoral neck) were all measured and analyzed.

RESULTS

The expression of COL-I in femoral neck were significantly decreased, whereas other markers were all significantly increased with the decreasing of femoral neck BMD and L_max (P < 0.05). Among them, serum C-terminal telopeptide of type I collagen (CTX) levels and OPN expression of femoral neck were increased in osteopenia. In multiple linear regression analysis, CTX and OPN were both negatively correlated with femoral neck BMD and L_max, and they were independent factors of femoral neck BMD and L_max, whereas COL-I was independent factor affecting L_max (P < 0.05). Besides, CTX was negatively correlated with COL-I (β = -0.275, P = 0.012) and positively correlated with OPN (β = 0.295, P = 0.003).

CONCLUSIONS

Compared with other indicators, serum CTX was more sensitive to differences in bone mass and bone strength of femoral neck, and could be considered as surrogate marker for OPN and COL-I.Early measurement of CTX could facilitate the diagnosis of osteopenia and provide a theoretical basis for delaying the occurrence of femoral neck OP and fragility fractures.

Emerging roles of circular RNAs in osteoporosis

Osteoporosis is one bone disease characterized with skeletal impairment, bone strength reduced and fracture risk enhanced. The regulation processes of bone metabolism are associated with several factors such as mechanical stimulation, epigenetic regulation and hormones. However, the mechanism of osteoporosis remains unsatisfactory. Increasing high‐throughput RNA sequencing and circular RNAs (circRNAs) microarray studies indicated that circRNAs are differentially expressed in osteoporosis. Growing functional studies further pinpointed specific deregulated expressed circRNAs (e.g., circ_28313, circ_0016624, circ_0006393, circ_0076906 and circ_0048211) for their functions involved in bone metabolism, including bone marrow stromal cells (BMSCs) differentiation, proliferation and apoptosis. Moreover, CircRNAs (circ_0002060, Circ_0001275 and Circ_0001445) may be acted as diagnostic biomarkers for osteoporosis. This review discussed recent progresses in the circRNAs expression profiling analyses and their potential functions in regulating BMSCs differentiation, proliferation and apoptosis.

Circular RNA_0062582 promotes osteogenic differentiation of human bone marrow mesenchymal stem cells via regulation of microRNA-145/CBFB axis

Osteoporosis poses a threat to human health worldwide. To date, there have been few studies regarding targeted treatment of osteoporosis. We aimed to identify the possible molecular mechanism of circular RNA (circ)_0062582 in osteogenic differentiation, and the interactions among circ_0062582, microRNA-145 (miR-145) and core-binding factor subunit β (CBFB). The proliferation of human bone marrow mesenchymal stem cells (hBMSCs) was tested with a cell counting kit-8 assay. Circ_0062582, miR-145 and CBFB were overexpressed by transient transfection. Dual-luciferase reporter assay system was used to analyze the combination among circ_0062582, miR-145 and CBFB. Additionally, the levels of circ_0062582, miR-145, CBFB, osterix (OSX), osteocalcin (OCN) and collagen type 1 (COL1) were detected by means of RT-qPCR or western blot analysis. Alkaline phosphatase and Alizarin red stainings were performed to analyze the degree of osteogenic differentiation under the control of circ_0062582, miR-145 and CBFB. The results demonstrated that circ_0062582 level was notably elvated during osteogenic differentiation of hBMSCs. Circ_0062582 overexpression significantly promoted osteogenic differentiation and upregulated the levels of osteogenic differentiation-related proteins, including OSX, OCN and COL1. In addition, miR-145, which was identified as the target gene of circ_0062582, could specifically target CBFB 3′-UTR regions. Next, these changes caused by the overexpression of circ_0062582 were reversed following the addition of miR-145 mimic. Following overexpression of CBFB, osteogenic differentiation was increased. In summary, these results demonstrated that the role of circ_0062582 in osteoporosis is mediated through regulating the expression level of CBFB via miR-145.

Assessment of bone quality at the lumbar and sacral spine using CT scans: a retrospective feasibility study in 50 comparing CT and DXA data

PURPOSE

Computed tomography (CT) is a standard diagnostic tool for preoperative screening for many indications in spinal and pelvic surgery. The gold standard for diagnosing osteoporosis is standard dual-energy X-ray absorptiometry (DXA). The aim of the present study was to compare the accuracy of Hounsfield unit (HU) measurements not only at the lower lumbar, but also at the sacral spine using standard CT scans.

PATIENTS AND METHODS

Main inclusion criterion for this retrospective analysis in 50 patients was the availability of both a CT scan of the lumbar and sacral spines and a DXA scan. HUs were measured in intact vertebral bodies L4, L5 and S1. Results of the HU in CT scan were compared to the T-score and bone mineral density in DXA. A group with normal bone density (T-score higher - 1, n = 26) was compared with a group with impaired bone density (T-score lower - 1, n = 24).

RESULTS

A multivariant binary logistic regression analysis showed significant results for HU measurement in L4 (p = 0.009), L5 (p = 0.005) and S1 (p = 0.046) with respect to differentiation between normal and impaired bone quality. Cutoffs between normal and impaired bone density values for trabecular region of interest attenuation for L4, L5 and S1 are presented. In L4 100% sensitivity to detect normal bone was reached when HU was higher than 161, HU higher than 157 in L5 and HU higher than 207 in S1.

CONCLUSIONS

HU measurements in CT scans have proven to be a feasible tool to additionally assess bone quality at the lumbar and sacral spine with good sensitivity, when compared with the gold standard DXA.

LEVEL OF EVIDENCE

III. These slides can be retrieved under Electronic Supplementary Material.

Sesamin Promotes Osteoblastic Differentiation and Protects Rats from Osteoporosis

Background

Osteoporosis is a common osteopathy, resulting in fractures, especially in elder people. Sesamin has many pharmacological effects, including supplying calcium. However, how sesamin might prevent osteoporosis is still under study.

Material/Methods

Bone marrow stromal cells (BMSCs) extracted from rat femur were induced for osteoblastic differentiation. Cell proliferation, alkaline phosphatase (ALP), osterix (OSX), SRY-box 9 (SOX9), runt-related transcription factor 2 (RUNX2), osteocalcin (OCN), β-catenin, low density lipoprotein receptor-related protein 5 (LRP5), and glycogen synthase kinase-3β (GSK-3β) levels in BMSCs were detected in the presence or absence of sesamin (1 μM or 10 μM). In addition, FH535 (1 μM) was used to silence Wnt/β-catenin in vitro. Ovariectomized (OVX) rats were established and intragastrically administrated sesamin (80 mg/kg), and then the rat bones were analyzed by micro-computed tomography. Osteocalcin and collagen type I were measured in the rat femurs.

Results

Sesamin had no influence on BMSC proliferation. Higher sesamin concentration promoted Wnt/β-catenin activity and enhanced more expressions of ALP, OSX, SOX9, RUNX2, and OCN, gradually and significantly (P<0.05). Silencing Wnt/β-catenin weakened the enhancement on RUNX2 and OCN expression. Sesamin (80 mg/kg) promoted bone structure in ovariectomized rats, and significantly enhanced osteocalcin and collage type I expression (P<0.05).

Conclusions

Sesamin promoted osteoblastic differentiation of rat BMSCs by regulating the Wnt/β-catenin pathway, and improved rat bone structure. Sesamin could have therapeutic and preventive effects on osteoporosis.