Analysis of altered microRNA expression profile in the reparative interface of the femoral head with osteonecrosis.

The reparative reaction is considered to be important during the occurrence of collapse in the femoral head with osteonecrosis (ONFH), but little is known about the long-term reparative process. The aim of this study was to determine and analyze the altered microRNA expression profile in the reparative interface of ONFH, and further validate the expression of the involved genes in the predicted pathways. Microarray analysis was performed comparing the reparative interface of patients with ONFH and normal tissue of patients with fresh femoral neck fracture (FNF) and partly validated by real-time PCR. Potential target genes of differentially expressed miRNAs were predicted by TargetScan and miRanda, and the target genes were used for further bioinformatics analysis such as Gene Ontology and Pathway assay. The filtered miRNAs and genes in the predict pathways were further examined by real-time PCR in another 6 independent ONFH patients. Among the 2578 miRNAs identified, 17 were consistently differentially expressed, 12 of which are up-regulated and 5 down-regulated. GO classification showed that the predicted target genes of these miRNAs are involved in signal transduction, cell differentiation, methylation, cell growth and apoptosis. The Kyoto Encyclopedia of Genes and Genomes (KEGG) classification indicated that these genes play a role in angiogenesis and Wnt signaling pathways. The expression of miR-34a and miR-146a and genes in the predict pathways were significantly up-regulated. This study presented a global view of miRNA expression in the reparative interface of osteonecrosis. In addition, our data provided novel and robust information for further researches in the pathogenesis and molecular events of ONFH.

Predictive value of single photon emission computerized tomography and computerized tomography in osteonecrosis after femoral neck fracture: a prospective study.

PURPOSE: Osteonecrosis of the femoral head (ONFH) is a very common complication after femoral neck fracture. The purpose of this study was to assess the femoral head vascularity after femoral neck fracture using single photon emission computerized tomography and computerized tomography (SPECT/CT), and to evaluate its value in predicting ONFH. METHODS: Between January 2008 and March 2011, 120 patients diagnosed with femoral neck fracture underwent SPECT-CT before the internal fixation. The fracture was classified according to the Garden classification. The ratios of the radionuclide uptake of the fractured femoral head to that of the contralateral femoral head (F/N) were calculated to assess the femoral head vascularity. After a minimum of two years' follow-up, magnetic resonance imaging (MRI) was used as the "gold standard" for the diagnosis of possible ONFH. RESULTS: A total of 114 patients completed the study. The SPECT/CT examination showed that the F/N ratios of Garden I, II, III and IV were 2.6, 1.8, 0.8, and 0.6, respectively. At the time of the most recent follow-up, osteonecrosis developed in two of the 27 patients who had a Garden Stage-II fracture, in eight of the 34 patients who had a Garden Stage-III fracture, and nine of the 27 patients who had a Garden Stage-VI fracture. With a cutoff of 0.55 from the receiver operating characteristic (ROC) curve, F/N ratio showed a sensitivity of 97%, a specificity of 79%, a positive predictive value of 95%, and a negative predictive value of 19%. CONCLUSION: SPECT-CT proved to be reliable and valid for predicting ONFH after femoral neck fracture.

Serum Biomarkers Related to Glucocorticoid-Induced Osteonecrosis of the Femoral Head: A Prospective Nested Case-Control Study.

Early diagnosis and prevention of glucocorticoid (GC)-induced osteonecrosis of the femoral head (ONFH) continues to be a challenging problem for clinicians and researchers. However, the role of circulating biomarkers for GC-induced ONFH, which may reveal individual susceptibility and facilitate earlier diagnosis, remains to be determined. The aim of this study was to identify potential biomarkers that may predict early GC-induced ONFH. A total of 123 patients scheduled for initial systemic GC therapy were enrolled in this prospective nested case-control study. The serum concentrations of 13 potential biomarkers were measured in seven patients with GC-induced ONFH, diagnosed instantly after short-term use of GCs and in 20 controls who did not develop osteonecrosis despite similar GC therapy. Biomarkers were measured both before and after taking GCs to identify any differences in marker levels and the changes during GC therapy between two groups. Type I collagen cross-linked C-telopeptide (ß-CTX; p = 0.000) was significantly lower, high-density lipoprotein cholesterol (p = 0.092) and apolipoprotein (apo)-B/apo-A1 (p = 0.085) tended to be lower and higher, respectively, before GC treatment in osteonecrosis group. After GC therapy, ß-CTX (p = 0.014) was significantly lower and amino terminal telopeptide of procollagen type I (PINP; p = 0.068) tended to be lower in the osteonecrosis group. As secondary outcomes, we observed remarkable changes in nine potential biomarkers following short-term GC therapy in both groups. In conclusion, we found that ß-CTX, could potentially be used to predict GC-induced ONFH before GC therapy. Lower ß-CTX and PINP are promising biomarkers for the early diagnosis of GC-induced ONFH. These findings need to be confirmed in large-scale prospective studies. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:2348-2357, 2019.

Clinical outcomes of osteonecrosis of the femoral head after autologous bone marrow stem cell implantation: a meta-analysis of seven case-control studies.

The purpose of this study was to evaluate the clinical outcomes of osteonecrosis of the femoral head after autologous bone marrow stem cell implantation. We searched the PubMed, Embase and Web of Science databases and included all case-control trials that reported on the clinical outcomes of osteonecrosis progression, incidence of total hip arthroplasty and improvement in Harris hip scores. Overall, seven case-control trials were included. Compared with the controls, patients treated with the bone marrow stem cells implantation treatment showed improved clinical outcomes with delayed osteonecrosis progression (odds ratio = 0.17, 95% CI: 0.09 - 0.32; p <0.001), a lower total hip arthroplasty incidence (odds ratio = 0.30, 95% CI: 0.12 - 0.72; p <0.01) and increased Harris hip scores (mean difference = 4.76, 95% CI: 1.24 - 8.28; p<0.01). The heterogeneity, publication bias, and sensitivity analyses showed no statistical difference significant differences between studies. Thus, our study suggests that autologous bone marrow stem cells implantation has a good therapeutic effect on osteonecrosis of the femoral, resulting in beneficial clinical outcomes. However, trials with larger sample sizes are needed to confirm these findings.

Involvement of MicroRNA-210 Demethylation in Steroid-associated Osteonecrosis of the Femoral Head.

Angiogenesis is an important event in steroid-associated osteonecrosis of the femoral head (SONFH). Here we performed miRNA microarray with SONFH tissues (ONs) and the adjacent normal tissues (NLs) to select the angiogenic miRNA. The results showed that miR-210 was differentially expressed in SONFH versus normal tissues. Unexpectedly, its specific transcription factor, hypoxia-inducible factor-1α, was shown of no significant changes in ONs compared with NLs. Further Bisulfite sequencing revealed that miR-210 is embedded in a CpG island and miR-210 gene has 2 CpG sites with lower methylation percentage in ONs compared with NLs. Additionally, ONs with lower miR-210 gene methylation exhibited higher miR-210 expression. Next, we found that the endothelial cells treated with demethylating agents could significantly increase the expression of miR-210, along with promoted cell viability and differentiation. Some angiogenic genes (VEGF, bFGF, TNF-α and PCNA) were up-regulated as well. In addition, the supernatant of the cells after demethylation treatment displayed an enhanced ability of recruiting new microvessels in vivo. Taken together, our study not only provides novel insights into the regulation of angiogenesis in this disease, but also reveals a therapeutic opportunity for treatment of SONFH patients with demethylating agents.

Protective effects of total saponins of panax notoginseng on steroid-induced avascular necrosis of the femoral head in vivo and in vitro.

This research was designed to investigate the protective effects of TSPN on steroid-induced avascular necrosis of the femoral head (ANFH) and the likely mechanisms of those effects. As an in vivo study, TSPN was shown to be protective against steroid-induced ANFH due to the upregulation of VEGF-A. Furthermore, TSPN attenuated the apoptosis of osteocytes and reduced the expression of Caspase-3 relative to the model group. As an in vitro study, TSPN exerted a concentration-dependent protective effect against apoptosis in MC3T3-E1 cells. Moreover, TSPN (at a dose of 100 µg/mL) significantly reversed the dexamethasone-induced augmentation of Caspase-3 expression and activity. Therefore, our study demonstrated that TSPN had a protective effect against steroid-induced ANFH that was related to the upregulation of VEGF-A and the inhibition of apoptosis and Caspase-3 activation.

Fabrication of modified dextran-gelatin in situ forming hydrogel and application in cartilage tissue engineering.

Hydrogels play a very important role in cartilage tissue engineering. Here, we oxidized dextran (Odex) and modified gelatin (Mgel) to fabricate a fast forming hydrogel without the addition of a chemical crosslinking agent. The dynamic gelling process was measured through rheological measurements. The microstructure was examined by lyophilizing to get porous scaffolds. Biological assessment was performed through CCK-8 assays by using synovium-derived mesenchymal cells (SMSCs) at 1, 3, 7 and 14 days. In vivo evaluation for application in cartilage tissue engineering was performed 8 weeks after subcutaneous injection of SMSC-loaded Odex/Mgel hydrogels combined with TGF-ß3 in the dorsa of nude mice. According to the results, a fast forming hydrogel was obtained by simply modifying dextran and gelatin. Moreover, the Odex/Mgel hydrogel exhibited good biocompatibility in cultures of SMSCs and a homogeneous distribution of live cells was achieved inside the hydrogels. After 8 weeks, newly formed cartilage was achieved in the dorsa of nude mice; no inflammatory reaction was observed and high production of GAGs was shown. The method provides a strategy for the design and fabrication of fast in situ forming hydrogels. The Odex/Mgel hydrogel could be used for the regeneration of cartilage in tissue engineering.

Clinical outcomes of osteonecrosis of the femoral head after autologous bone marrow stem cell implantation: a meta-analysis of seven case-control studies

The purpose of this study was to evaluate the clinical outcomes of osteonecrosis of the femoral head after autologous bone marrow stem cell implantation. We searched the PubMed, Embase and Web of Science databases and included all case-control trials that reported on the clinical outcomes of osteonecrosis progression, incidence of total hip arthroplasty and improvement in Harris hip scores. Overall, seven case-control trials were included. Compared with the controls, patients treated with the bone marrow stem cells implantation treatment showed improved clinical outcomes with delayed osteonecrosis progression (odds ratio = 0.17, 95% CI: 0.09 - 0.32; p <0.001), a lower total hip arthroplasty incidence (odds ratio = 0.30, 95% CI: 0.12 - 0.72; p <0.01) and increased Harris hip scores (mean difference = 4.76, 95% CI: 1.24 - 8.28; p<0.01). The heterogeneity, publication bias, and sensitivity analyses showed no statistical difference significant differences between studies. Thus, our study suggests that autologous bone marrow stem cells implantation has a good therapeutic effect on osteonecrosis of the femoral, resulting in beneficial clinical outcomes. However, trials with larger sample sizes are needed to confirm these findings.