Aucubin suppresses TLR4/NF-κB signalling to shift macrophages toward M2 phenotype in glucocorticoid-associated osteonecrosis of the femoral head.

In this study, we investigated whether the ability of aucubin to mitigate the pathology of GONFH involves suppression of TLR4/NF-κB signalling and promotion of macrophage polarization to an M2 phenotype. In necrotic bone tissues from GONFH patients, we compared levels of pro-inflammatory M1 macrophages and anti-inflammatory M2 macrophages as well as levels of TLR4/NF-κB signalling. In a rat model of GONFH, we examined the effects of aucubin on these parameters. We further explored its mechanism of action in a cell culture model of M1 macrophages. Necrotic bone tissues from GONFH patients contained a significantly increased macrophage M1/M2 ratio, and higher levels of TLR4, MYD88 and NF-κB p65 than bone tissues from patients with hip osteoarthritis. Treating GONFH rats with aucubin mitigated bone necrosis and demineralization as well as destruction of trabecular bone and marrow in a dose-dependent manner, based on micro-computed tomography. These therapeutic effects were associated with a decrease in the overall number of macrophages, decrease in the proportion of M1 macrophages, increase in the proportion of M2 macrophages, and downregulation of TLR4, MYD88 and NF-κB p65. These effects in vivo were confirmed by treating cultures of M1 macrophage-like cells with aucubin. Aucubin mitigates bone pathology in GONFH by suppressing TLR4/NF-κB signalling to shift macrophages from a pro- to anti-inflammatory phenotype.

Crebanine mitigates glucocorticoid-induced osteonecrosis of the femoral head by restoring bone remodelling homeostasis via attenuating oxidative stress.

The onset of osteonecrosis of the femoral head (ONFH) is intimately associated with the extensive administration of glucocorticoids (GCs). Long-term stimulation of GCs can induce oxidative stress in both osteoclasts (OCs) and osteoblasts (OBs), resulting in the disturbance of bone remodelling. An alkaloid named crebanine (CN) demonstrates pharmacological properties including anti-inflammation and reactive oxygen species (ROS) modulation. Our objective is to assess the therapeutic potential of CN in treating ONFH and elucidate the associated underlying mechanisms. The network pharmacology analysis uncovered that CN played a role in regulating ROS metabolism. In vitro, CN demonstrated its ability to reduce the dexamethasone (DEX)-stimulated generation of OCs and suppress their resorptive function by downregulating the level of osteoclast marker genes. Concurrently, CN also mitigated DEX-induced damage to OBs, facilitating the restoration of osteoblast marker gene expression, cellular differentiation and function. These effects were achieved by CN augmenting the antioxidant system to reduce intracellular ROS levels. Furthermore, in vitro results were corroborated by micro-CT and histological data, which also showed that CN attenuated MPS-induced ONFH in mice. This study highlights the therapeutic potential of CN in counteracting GCs-induced ONFH.

Lithium prevents glucocorticoid-induced osteonecrosis of the femoral head by regulating autophagy.

Autophagy may play an important role in the occurrence and development of glucocorticoid-induced osteonecrosis of the femoral head (GC-ONFH). Lithium is a classical autophagy regulator, and lithium can also activate osteogenic pathways, making it a highly promising therapeutic agent for GC-ONFH. We aimed to evaluate the potential therapeutic effect of lithium on GC-ONFH. For in vitro experiments, primary osteoblasts of rats were used for investigating the underlying mechanism of lithium's protective effect on GC-induced autophagy levels and osteogenic activity dysfunction. For in vivo experiments, a rat model of GC-ONFH was used for evaluating the therapeutic effect of oral lithium on GC-ONFH and underlying mechanism. Findings demonstrated that GC over-activated the autophagy of osteoblasts and reduced their osteogenic activity. Lithium reduced the over-activated autophagy of GC-treated osteoblasts through PI3K/AKT/mTOR signalling pathway and increased their osteogenic activity. Oral lithium reduced the osteonecrosis rates in a rat model of GC-ONFH, and restrained the increased expression of autophagy related proteins in bone tissues through PI3K/AKT/mTOR signalling pathway. In conclusion, lithium can restrain over-activated autophagy by activating PI3K/AKT/mTOR signalling pathway and up-regulate the expression of genes for bone formation both in GC induced osteoblasts and in a rat model of GC-ONFH. Lithium may be a promising therapeutic agent for GC-ONFH. However, the role of autophagy in the pathogenesis of GC-ONFH remains controversial. Studies are still needed to further explore the role of autophagy in the pathogenesis of GC-ONFH, and the efficacy of lithium in the treatment of GC-ONFH and its underlying mechanisms.

Omaveloxolone ameliorates glucocorticoid-induced osteonecrosis of the femoral head by promoting osteogenesis and angiogenesis.

Steroid (glucocorticoid)-induced necrosis of the femoral head (SONFH) represents a prevalent, progressive, and challenging bone and joint disease characterized by diminished osteogenesis and angiogenesis. Omaveloxolone (OMA), a semi-synthetic oleanocarpane triterpenoid with antioxidant, anti-inflammatory, and osteogenic properties, emerges as a potential therapeutic agent for SONFH. This study investigates the therapeutic impact of OMA on SONFH and elucidates its underlying mechanism. The in vitro environment of SONFH cells was simulated by inducing human bone marrow mesenchymal stem cells (hBMSCs) and human umbilical vein endothelial cells (HUVECs) using dexamethasone (DEX).Various assays, including CCK-8, alizarin red staining, Western blot, qPCR, immunofluorescence, flow cytometry, and TUNNEL, were employed to assess cell viability, STING/NF-κB signaling pathway-related proteins, hBMSCs osteogenesis, HUVECs migration, angiogenesis, and apoptosis. The results demonstrate that OMA promotes DEX-induced osteogenesis, HUVECs migration, angiogenesis, and anti-apoptosis in hBMSCs by inhibiting the STING/NF-κB signaling pathway. This experimental evidence underscores the potential of OMA in regulating DEX-induced osteogenesis, HUVECs migration, angiogenesis, and anti-apoptosis in hBMSCs through the STING/NF-κB pathway, thereby offering a promising avenue for improving the progression of SONFH.

[Research progress on mechanism of traditional Chinese medicine intervention in angiogenesis in prevention and treatment of nontraumatic avascular necrosis of femoral head].

Nontraumatic avascular necrosis of the femoral head(NANFH) is a common and refractory femoral head disease that causes bone death due to interruption of blood supply. Early clinical symptoms are atypical, such as hip pain and limited joint function. In the late stage, severe pain, shortening of the affected limb, claudication, and other serious symptoms are common, which se-riously affects the quality of life of patients. Therefore, it is of great significance to actively improve the clinical symptoms of NANFH to enhance the quality of life of patients. The pathogenesis of NANFH is complex, such as traumatic vascular circulatory disorders, the use of hormones or other drugs, alcoholism, and diabetes mellitus. These factors directly or indirectly lead to femoral head vascular damage, thrombosis, and coagulation system disorders, which reduce the blood supply to the acetabulum and femoral head, thus causing ischaemic death of the femoral head or even femoral head collapse. NANFH is mainly categorized as "bone impotence" and "bone paralysis" in traditional Chinese medicine(TCM). The treatment of NANFH with TCM has the characteristics and advantages of a long history, stable and reliable therapeutic effect, fewer adverse reactions, good patient tolerance, and high acceptance. Previous studies have shown that the promotion of angiogenesis is a key initiative in the prevention and treatment of NANFH, and TCM can promote fe-moral head angiogenesis by interfering with the expression of angiogenesis-related factors, which in turn can help to restore the blood supply of the femoral head and thus improve clinical symptoms of NANFH and prevent and treat NANFH. This article described the roles of blood supply interruption and angiogenesis in NANFH and the accumulated knowledge and experience of TCM in NANFH and summarized the role of angiogenesis-related factors in NANFH and the research progress on TCM intervention, so as to provide an idea for the subsequent research and a new basis for the clinical application of TCM in the treatment of NANFH.

Effects of Puerarin-Loaded Tetrahedral Framework Nucleic Acids on Osteonecrosis of the Femoral Head.

Osteonecrosis of the femoral head (ONFH) is recognized as a common refractory orthopedic disease that causes severe pain and poor quality of life in patients. Puerarin (Pue), a natural isoflavone glycoside, can promote osteogenesis and inhibit apoptosis of bone mesenchymal stem cells (BMSCs), demonstrating its great potential in the treatment of osteonecrosis. However, its low aqueous solubility, fast degradation in vivo, and inadequate bioavailability, limit its clinical application and therapeutic efficacy. Tetrahedral framework nucleic acids (tFNAs) are promising novel DNA nanomaterials in drug delivery. In this study, tFNAs as Pue carriers is used and synthesized a tFNA/Pue complex (TPC) that exhibited better stability, biocompatibility, and tissue utilization than free Pue. A dexamethasone (DEX)-treated BMSC model in vitro and a methylprednisolone (MPS)-induced ONFH model in vivo is also established, to explore the regulatory effects of TPC on osteogenesis and apoptosis of BMSCs. This findings showed that TPC can restore osteogenesis dysfunction and attenuated BMSC apoptosis induced by high-dose glucocorticoids (GCs) through the hedgehog and Akt/Bcl-2 pathways, contributing to the prevention of GC-induced ONFH in rats. Thus, TPC is a promising drug for the treatment of ONFH and other osteogenesis-related diseases.

Ursolic acid alleviates steroid-induced avascular necrosis of the femoral head in mouse by inhibiting apoptosis and rescuing osteogenic differentiation.

Steroid-induced avascular necrosis of femoral head (SANFH) is a common disorder worldwide with high disability. Overdose of glucocorticoid (GC) is the most common non-traumatic cause of SANFH. Up until now, there are limited therapeutic strategies for curing SANFH, and the mechanisms underlying SANFH progression remain unclear. Nevertheless, Osteogenic dysfunction is considered to be one of the crucial pathobiological mechanisms in the development of SANFH, which involves mouse bone marrow mesenchymal stem cells (BMSCs) apoptosis and osteogenic differentiation disorder. Ursolic acid (UA), an important component of the Chinese medicine formula Yougui Yin, has a wide range of pharmacological properties such as anti-tumor, anti-inflammatory and bone remodeling. Due to the positive effect of Yougui Yin on bone remodeling, the purpose of this study was to investigate the effects of UA on dexamethasone (DEX)-induced SANFH in vitro and vivo. In vitro, we demonstrated that UA can promote mouse BMSCs proliferation and resist DEX-induced apoptosis by CCK8, Western blotting, TUNEL and so on. In addition, vitro experiments such as ALP and Alizarin red staining assay showed that UA had a beneficial effect on the osteogenic differentiation of mouse BMSCs. In vivo, the results of H&E staining, immunohistochemistry staining, Elisa and micro-CT analysis showed that UA had a bone repair-promoting effect in SANFH model. Moreover, the results of Western blot and TUNEL experiments showed that UA could delay the disease progression of SANFH in mice by inhibiting apoptosis. Overall, our study suggests that UA is a potential compound for the treatment of SANFH.

Erythropoietin suppresses osteoblast apoptosis and ameliorates steroid-induced necrosis of the femoral head in rats by inhibition of STAT1-caspase 3 signaling pathway.

BACKGROUND: Steroid-induced avascular necrosis of the femoral head (SANFH) is characterized by osteoblast apoptosis, leading to a loss of bone structure and impaired hip joint function. It has been demonstrated that erythropoietin (EPO) performs a number of biological roles. OBJECTIVE: We examined the effects of EPO on SANFH and its regulation of the STAT1-caspase 3 signaling pathway. METHOD: In vitro, osteoblasts were treated with dexamethasone (Dex) or EPO. We identified the cytotoxicity of EPO by CCK-8, the protein expression of P-STAT1, cleaved-caspase9, cleaved-caspase3, Bcl-2, BAX, and cytochrome c by Western blotting, and evaluated the apoptosis of osteoblasts by flow cytometry. In vivo, we analyzed the protective effect of EPO against SANFH by hematoxylin and eosin (H&E), Immunohistochemical staining, and Micro-computed tomography (CT). RESULTS: In vitro, EPO had no apparent toxic effect on osteoblasts. In Dex-stimulated cells, EPO therapy lowered the protein expression of BAX, cytochrome c, p-STAT1, cleaved-caspase9, and cleaved-caspase3 while increasing the expression of Bcl-2. EPO can alleviate the apoptosis induced by Dex. In vivo, EPO can lower the percentage of empty bone lacunae in SANFH rats. CONCLUSION: The present study shows that EPO conferred beneficial effects in rats with SANFH by inhibiting STAT1-caspase 3 signaling, suggesting that EPO may be developed as a treatment for SANFH.

An injectable hydroxypropyl-ß-cyclodextrin cross-linked gelatin-based hydrogel loaded bone mesenchymal stem cell for osteogenic and in vivo bone regeneration of femoral head necrosis.

An injectable hydroxypropyl-ß-cyclodextrin (HPßCD) cross-linking of gelatin (Gel) based hydrogel was embedded with BMSC in vivo bone regeneration of femoral head necrosis. This HPßCD-Gel hydrogel possesses quick gelation within 6 min; a high-water uptake resulted in faster biodegradation, high swelling, and a 3D porous network that strengthened its mechanical, surface, and morphological properties. The results indicated that BMSC showed high cell viability (>90%) during measurement; HPßCD-Gel hydrogels induced BMSC differentiation into osteocytes within 14 days more efficiently than the osteogenic medium. The HPßCD-Gel/BMSC hydrogels that were injected into the necrosis site of the femoral head in the vessels were measured for 2 weeks. In addition, the vessel density and mean vessel diameters increased in the next 2-8 weeks followed by increased new bone formation, according to the in vivo analysis. Overall, our findings show that this method is a promising strategy for improving femoral head necrosis bone regeneration.

Identification of key non-coding RNAs and transcription factors regulators and their potential drugs for steroid-induced femoral head necrosis.

Steroid-induced necrosis of femoral head (SINFH) is a femoral head necrotic disease caused by prolonged use of hormones. The detailed pathogenesis has not been fully demonstrated. In this study, we employed the bioinformatics approach to probe the roles of SINFH inhibitors. Core dysfunction modules related to SINFH was obtained. Meanwhile, GO and KEGG analysis of genes in dysfunction modules are carried out. Furthermore, the pivot prediction analysis of dysfunction modules related to ncRNA and transcription factor (TF) has been performed. The functions of the enriched modules were focused on multiple perspectives, including circulation, gland development, bone development and reconstruction, calcium production, and fatty acid metabolism regulation. The ncRNAs and TFs analysis showed that miR-322-5p, miR-124-3p, miR-125a-3p, and Ctnnb1 were important members of SINFH dysfunction. Drug targets suggested that Zinc and adenosine monophosphate may have an impact on SINFH dysfunction. SINFH was closely related to bone development and reconstruction.

Glucocorticoids decreased Cx43 expression in osteonecrosis of femoral head: The effect on proliferation and osteogenic differentiation of rat BMSCs.

Glucocorticoid (GC)-induced osteonecrosis of the femoral head (GC-ONFH) is considered as one of the most serious side effects of long-term or over-dose steroid therapy. However, the underlying cause mechanisms are still not fully investigated. We firstly established a rat model of GC-ONFH and injected lipopolysaccharide (LPS) and methylprednisolone (MPS). We found that the expressions of Cx43, Runx2, ALP and COLⅠ were more decreased than the normal group. Secondly, the isolated rat bone marrow stem cells (BMSCs) were treated with dexamethasone (Dex) in vitro, and the expressions of Cx43, Runx2, ALP and COLⅠ were decreased significantly. Moreover, the results of immunofluorescence staining, alizarin red staining, EdU assay and CCK8 showed that the osteogenic differentiation and the proliferation capacity of BMSCs were decreased after induced by Dex. A plasmid of lentivirus-mediated Cx43 (Lv-Cx43) gene overexpression was established to investigate the function of Cx43 in BMSCs under the Dex treatment. Findings demonstrated that the proliferation and osteogenic differentiation abilities were enhanced after Lv-Cx43 transfected to BMSCs, and these beneficial effects of Lv-Cx43 were significantly blocked when PD988059 (an inhibitor of ERK1/2) was used. In conclusion, the overexpression of Cx43 could promote the proliferation and osteogenic differentiation of BMSCs via activating the ERK1/2 signalling pathway, which provide a basic evidence for further study on the detailed function of Cx43 in GC-ONFH.

Protective effect of Agrimonia pilosa polysaccharides on dexamethasone-treated MC3T3-E1 cells via Wnt/ß-Catenin pathway.

A water-soluble polysaccharide (APP-AW) was isolated from Agrimonia pilosa and prepared to three sulphated derivatives (S1, S2 and S3). The results showed that pre-treatment with APP-AW, S1, S2 and S3 each at the concentration of 50 µg/mL for 48 hours was able to prevent cytotoxicity induced by 1 µmol/L dexamethasone (Dex) in MC3T3-E1 cells via inhibition of apoptosis, which is in line with the findings in flow cytometry analysis. Meanwhile, the decreased ALP activity, collagen content, mineralization, BMP2, Runx2, OSX and OCN protein expression in DEX-treated MC3T3-E1 cells were reversed by the addition of APP-AW, S1, S2 and S3. Moreover, APP-AW, S1, S2 and S3 rescued DEX-induced increase of Bax, cytochrome c and caspase-3 and decrease of Bcl-2, Wnt3, ß-catenin and c-Myc protein expression in MC3T3-E1 cells. Our findings suggest that pre-treatment with APP-AW, S1, S2 and S3 could significantly protect MC3T3-E1 cells against Dex-induced cell injury via inhibiting apoptosis and activating Wnt/ß-Catenin signalling pathway, thus application of these polysaccharides may be a promising alternative strategy for steroid-induced avascular necrosis of the femoral head (SANFH) therapy.

Osthole stimulates bone formation, drives vascularization and retards adipogenesis to alleviate alcohol-induced osteonecrosis of the femoral head.

Characteristic pathological changes in osteonecrosis of the femoral head (ONFH) include reduced osteogenic differentiation of bone mesenchymal stem cells (BMSCs), impaired osseous circulation and increased intramedullary adipocytes deposition. Osthole is a bioactive derivative from coumarin with a wide range of pharmacotherapeutic effects. The aim of this study was to unveil the potential protective role of osthole in alcohol-induced ONFH. In vitro, ethanol (50 mmol/L) remarkably decreased the proliferation and osteogenic differentiation of BMSCs and impaired the proliferation and tube formation capacity of human umbilical vein endothelial cell (HUVECs), whereas it substantially promoted the adipogenic differentiation of BMSCs. However, osthole could reverse the effects of ethanol on osteogenesis via modulating Wnt/ß-catenin pathway, stimulate vasculogenesis and counteract adipogenesis. In vivo, the protective role of osthole was confirmed in the well-constructed rat model of ethanol-induced ONFH, demonstrated by a cascade of radiographical and pathological investigations including micro-CT scanning, haematoxylin-eosin staining, TdT-mediated dUTP nick end labelling, immunohistochemical staining and fluorochrome labelling. Taken together, for the first time, osthole was demonstrated to rescue the ethanol-induced ONFH via promoting bone formation, driving vascularization and retarding adipogenesis.

Self-healing and injectable hybrid hydrogel for bone regeneration of femoral head necrosis and defect.

BACKGROUND: HA modified by bisphosphonate (BP) (HA-BP) was synthesized by chemical reaction and possessed promising properties such as self-healing, injection ability, and strong adhesion. The main aim of this study was to confirm its role in promoting osteogenic differentiation in vitro and bone regeneration in vivo. METHODS: The cell biocompatibility of this material was determined using the CCK-8 assay. Alkaline phosphatase (ALP), osteocalcin (OT), vascular endothelial growth factor (VEGF), and collagen I were assessed by quantitative real-time polymerase chain reaction (Q-PCR) in the treated group. The number and density of calcium nodules and ALP were evaluated by Alizarin Red staining and ALP staining. We have successfully developed an animal model simulating osteonecrosis of the femoral head (ONFH). Utilizing this animal model, the impact of HA-BP/CaP on bone formation was assessed. The amount of bone regeneration at 1 and 2 months after HA-BP/CaP injection was estimated by micro-computed tomography (micro-CT) analysis and H&E, collagen I, and periostin staining. RESULTS: The number of cells gradually increased in the experimental group over time and was close to that of the blank control group. ALP, collagen I, and VEGF expression was significantly higher in the experimental group than in the blank group (VEGF, ALP, both **p < 0.01; collagen I, ***p<0.001). In addition, the number and density of calcium nodules and ALP was clearly greater in the material group than in the control group. The quantification analysis showed that the mineral contents of regenerated bone at 1 and 2 months after HA-BP/CaP injection were significantly greater than those in the control group, according to micro-CT evaluation (**p<0.01). The amount of organic components in the HA-BP/CaP group was greater than that in the control group after decalcification and H&E staining. In addition, collagen I and periostin staining further confirmed the results of H&E staining. CONCLUSION: This material can boost proliferation and osteogenic differentiation of MC3T3-E1 cells in vitro. It can intensely accelerate bone regeneration in vivo, which is a promising strategy for tissue engineering.

Downregulating STAT1/caspase-3 signaling with fludarabine to alleviate progression in a rat model of steroid-induced avascular necrosis of the femoral head.

Steroid-induced avascular necrosis of the femoral head (SANFH) is mainly induced by glucocorticoids. Fludarabine (Flu) is a specific signal transducer and activator of transcription 1 (STAT1) inhibitor. In this study, we investigated the effect of Flu on SANFH and the role played by the STAT1/caspase-3 signaling pathway. Sprague-Dawley rats were divided into control, SANFH, and Flu-treated SANFH groups. Femoral head tissues were collected for hematoxylin-eosin (H&E) staining and Western blot analysis. The latter was used to measure the levels of stat1, phospho-stat1, caspase-3, cleaved caspase-3, caspase-9, cleaved caspase-9, Bax, cytochrome C, Bak, B-cell lymphoma-extra large, and B-cell lymphoma-2 protein expression. The results showed that Flu regulates protein expression in dexamethasone (Dex)-induced SANFH. H&E staining showed a decrease in the ratio of empty lacunae induced by Dex. Taken together, our study demonstrated the involvement of the STAT1/caspase-3 signaling pathway in SANFH and the potential of Flu as a therapeutic agent for patients with SANFH.

Long Non-Coding RNA MALAT1 Protects Human Osteoblasts from Dexamethasone-Induced Injury via Activation of PPM1E-AMPK Signaling.

BACKGROUND/AIMS: Dexamethasone (Dex) induces injuries to human osteoblasts. In this study, we tested the potential role of the long non-coding RNA metastasis-associated lung adenocarcinoma transcript 1 (Lnc-MALAT1) in this process. MATERIALS: Two established human osteoblastic cell lines (OB-6 and hFOB1.19) and primary human osteoblasts were treated with Dex. Lnc-MALAT1 expression was analyzed by quantitative real-time polymerase chain reaction assay. Cell viability, apoptosis, and death were tested by the MTT assay, histone-DNA assay, and trypan blue staining assay, respectively. AMP-activated protein kinase (AMPK) signaling was evaluated by western blotting and AMPK activity assay. RESULTS: Lnc-MALAT1 expression was downregulated by Dex treatment in the established osteoblastic cell lines (OB-6 and hFOB1.19) and primary human osteoblasts. The level of Lnc-MALAT1 was decreased in the necrotic femoral head tissues of Dex-administered patients. In osteoblastic cells and primary human osteoblasts, forced overexpression of Lnc-MALAT1 using a lentiviral vector (LV-MALAT1) inhibited Dex-induced cell viability reduction, cell death, and apoptosis. Conversely, transfection with Lnc-MALAT1 small interfering RNA aggravated Dex-induced cytotoxicity. Transfection with LV-MALAT1 downregulated Ppm1e (protein phosphatase, Mg2+/ Mn2+-dependent 1e) expression to activate AMPK signaling. Treatment of osteoblasts with AMPKα1 short hairpin RNA or dominant negative mutation (T172A) abolished LV-MALAT1-induced protection against Dex-induced cytotoxicity. Furthermore, LV-MALAT1 induced an increase in nicotinamide adenine dinucleotide phosphate activity and activation of Nrf2 signaling. Dex-induced reactive oxygen species production was significantly attenuated by LV-MALAT1 transfection in osteoblastic cells and primary osteoblasts. CONCLUSION: Lnc-MALAT1 protects human osteoblasts from Dex-induced injuries, possibly via activation of Ppm1e-AMPK signaling.

Combined pharmacotherapy for osteonecrosis of the femoral head after severe acute respiratory syndrome and interstitial pneumonia: two and a half to fourteen year follow-up.

PURPOSE: The purpose of this study was to retrospectively analyze the clinical, functional, and radiological outcomes of combined pharmacotherapy to ONFH after high-dose corticosteroid therapy. METHOD: From August 2003 to June 2015, five patients (ten hips) of ONFH in ARCO stage I, after SARS and Interstitial pneumonia, were treated by combined pharmacotherapy. Lipo-prostaglandin E1 10 µg iv Bid × 28 days, enoxaparin 6000 iu H QD × 12 weeks, alendronate sodium tablet 10 mg QD × 1 year. The patients were fully weight-bearing following completion of the follow-up. RESULT: For these five patients (ten hips), Harris score was 100 from the diagnosis to final follow-up time. Radiologic findings show no signs of collapse, necrotic focus was repaired, and ARCO stages were changed from IC into IIB. CONCLUSION: This combined pharmacotherapy has promising treatment results for delaying or preventing collapse of ONFH in ARCO stage I.

Fludarabine inhibits STAT1-mediated up-regulation of caspase-3 expression in dexamethasone-induced osteoblasts apoptosis and slows the progression of steroid-induced avascular necrosis of the femoral head in rats.

Steroid-induced avascular necrosis of the femoral head (SANFH) is a major limitation of long-term or excessive clinical administration of glucocorticoids. Fludarabine, which is a compound used to treat various hematological malignancies, such as chronic lymphocytic leukemia, acts by down-regulating signal transducer and activator of transcription 1 (STAT1) by inhibiting STAT1 phosphorylation in both normal and cancer cells. This study assessed the effects of fludarabine in vitro (primary murine osteoblasts) and in vivo (rat SANFH model). In vitro, pretreatment with fludarabine significantly inhibited Dexamethasone (Dex)-induced apoptosis in osteoblasts, which was examined by TUNEL staining. Treatment with Dex caused a remarkable decrease in the expression of Bcl-2; an increase in cytochrome c release; activation of BAX, caspase-9, and caspase-3; and an obvious enhancement in STAT1 phosphorylation. However, treatment resulted in the up-regulation of caspase-3 expression. Enhanced P-STAT1 activity and up-regulation of caspase-3 expression were also observed in osteoblasts. In vivo, the subchondral trabeculae in fludarabine-treated rats exhibited less bone loss and a lower ratio of empty lacunae. Taken together, our results suggest that STAT1-mediated up-regulation of caspase-3 is involved in osteoblast apoptosis induced by Dex and indicates that fludarabine may serve as a potential agent for the treatment of SANFH.

Rational derivation, extension, and cyclization of self-inhibitory peptides to target TGF-ß/BMP signaling in ONFH.

The human transforming growth factor ß (TGF-ß)/bone morphogenic protein (BMP) signaling has been recognized as an attractive target to suppress fibroblast activation in osteonecrosis of the femoral head (ONFH). Here, we reported successful derivation of a self-inhibitory peptide from the crystal complex interface of TGF-ß with its cognate receptor TßRI using rational molecular design and in vitro binding assay. Computational modeling suggested that the peptide possesses a large flexibility and would incur considerable entropy penalty. To minimize the entropy effect, the peptide was extended and cyclized to obtain a modified version of cyclic peptide. Molecular dynamics (MD) simulations revealed that the cyclic peptide exhibits larger rigidity and lower thermal motion in unbound state as compared to its linear counterpart, thus causing less entropy penalty upon binding to TGF-ß. The computational findings were then substantiated by fluorescence polarization (FP) assays, that is, no binding affinity was detected for linear peptide (K d = n.d.), while cyclic version was determined to have a moderate affinity (K d = 76 ± 18 µM). Structural and energetic analysis identified two anchor residues Phe60 and Ser65 in cyclic peptide that can form a π-π stacking and a hydrogen bonding with the residues Trp30 and His68 of TGF-ß, respectively, conferring high stability and specificity to the complex system.

Efficacy of teriparatide in the treatment of nontraumatic osteonecrosis of the femoral head: a retrospective comparative study with alendronate.

BACKGROUND: Collapse of the femoral head associated with nontraumatic osteonecrosis (NOFH) is one of the most common causes of disability in young adult patients. Excessive bone resorption by osteoclast coincident with the suppression of osteogenesis are believed to be responsible for collapse progression. Alendronate that inhibits bone resorption by inducing osteoclast apoptosis has been traditionally used for treating NOFH; however, several reports documented serious complications by the use of this drug. On the other hand, teriparatide activates osteoblasts leading to an overall increase in bone volume, and is expected to reduce the progression of femoral head collapse in NOFH. Therefore, the present study was undertaken to examine pharmacological effects of teriparatide on collapse progression of NOFH and to compare these effects with alendronate. METHODS: We conducted a retrospective study in our facility for comparing the pharmacological effects of teriparatide and alendronate on 32 NOFH patients diagnosed with osteoporosis. Between 2007 and 2013, patients were treated with daily administration of 20 µg teriparatide (15 patients: 18 hips), or with 35 mg of alendronate once a week (17 patients: 22 hips). The mean period of follow-up was 18.7 months. The progression of collapse was evaluated prior to the administration and later every three months by anteroposterior radiographs. Collapse progression with > 1 mm was defined as advanced collapse, while with < 1 mm was defined as stable radiologic disease. Student's t-test and the chi-square test was used to do compare the pharmacological effects of the two groups. RESULTS: Treatment with terparatide had a tendency to reduce the rate of advanced collapse as compared to that with alendronate (p = 0.105). Kaplan-Meier curves related to stable radiologic disease showed that teriparatide-treated patients had better stable states than these treated with alendronate (p = 0.08, log-rank test). Moreover, treatment with teriparatide resulted in a significant reduction in collapse progression as compared to that with alendronate, noted at the end of follow-up period (p = 0.049). CONCLUSION: The present study suggests that teriparatide has greater pharmacological effects than alendronate for treating NOFH and preventing the collapse of femoral head. TRIAL REGISTRATION: The registration number in UMIN Clinical Trial Registry is UMIN000017582 . The date of registration is May 5, 2015.