A polysaccharide from the dried rhizome of Drynaria fortunei (Kunze) J. Sm. prevents ovariectomized (OVX)-induced osteoporosis in rats.

In the present study, a homogenous polysaccharide (DFPW) was isolated and purified from the dried rhizome of Drynaria fortunei, and its protective effect against osteoporosis was investigated in ovariectomized (OVX) rats. Histological analysis indicated that oral administration of DFPW (100 and 400 mg/kg) for 12 weeks significantly improved trabecular bone mass, as demonstrated by the increase in trabecular area, trabecular thickness and its number in OVX rats. Furthermore, the decline of bone mineral density and bone mineral content including Ca, P and Mg induced by OVX was reversed by the DFPW administration. This function was achieved by the decreased levels of the bone turnover markers, such as serum ALP, urinary deoxypyridinoline (DPD), Ca and P excretions. Besides, DFPW improved biomechanical parameters (maximum load, energy, Young's, modulus and maximum stress) to strengthen the hardness and strength femoral diaphysis in OVX rats. These results strongly suggested that DFPW might be a hopeful alternative therapeutics to treat postmenopausal osteoporosis.

Suppressive oligodeoxynucleotide-induced dendritic cells rein the aggravation of osteoarthritis in mice.

OBJECTIVE: To explore the effect of suppressive oligodeoxynucleotide-induced dendritic cells (S-DCs) in the osteoarthritis (OA) therapy. METHODS: S-DCs were prepared from splenic CD11c + cells by in vitro culture with suppressive oligodeoxynucleotide. The function and phenotypes of S-DCs were measured by ELISA and flow cytometry. The innate immune signaling pathways were detected by western blotting in the non-treated DCs and S-DCs upon stimulation. In vivo, we employed an iodoacetate-induced OA mice model. S-DCs were transferred by intravenous route. The weight bearing of mice was evaluated and pro-inflammatory factors in OA joint were measured by real-time PCR. Treg cell ratio and CD4 + IL10+ cells in spleen were detected by flow cytometry at day 5 post OA induction. RESULTS: The S-DCs showed less inflammatory phenotypes upon stimulation. The expression of pro-inflammatory cytokines and mature makers in the S-DCs were blunt, due to the impaired innate immune signal transduction. In an iodoacetate-induced OA model, transfer of S-DCs significantly controlled the process of OA. Restricted inflammatory responses were observed in the joint of S-DC recipients. Moreover, after S-DC transfer, Tregs and CD4 + IL10+ cells were mounted in the spleen. CONCLUSION: Transfer of suppressive oligodeoxynucleotides-induced autologous DCs may represent a potential agent to control the aggravation of OA in patients.

Indole-3-carbinol as inhibitors of glucocorticoid-induced apoptosis in osteoblastic cells through blocking ROS-mediated Nrf2 pathway.

Apoptosis of osteoblasts induced by glucocorticoid (GC) has been identified as a main cause of osteoporosis, bone loss and fractures, and the oxidative stress was found as an important contributor. Therefore, natural or synthetic agents with antioxidant activities can antagonize GCs-induced apoptosis in osteoblasts, and thus demonstrate the potential application to reverse osteoporosis. In this study, we showed that, indole-3-carbinol (I3C), a natural product found in broadly consumed plants of the Brassica genus, could block the cytotoxic effects of dexamethasone (Dex), and elucidated the underlying molecular mechanisms. Firstly, we showed that, I3C could effectively suppress Dex-induced cytotoxicity and apoptotic cell death in osteoblastic cells, as evidenced by the decrease in Sub-G1 cell population. Treatment of the cells with Dex resulted in activation of caspase-3/-8/-9 and subsequent cleavage of PARP, which was also effectively blocked by co-incubation of I3C. Moreover, exposure to Dex triggered a rapid onset and time-dependent superoxide overproduction in osteoblastic cells, which was effectively suppressed by addition of I3C. Excess intracellular ROS induced by Dex significantly suppressed the expression levels of Nrf2 and the downstream effectors, HO1 and NQO1, but these changes could be reversed by I3C. Knockdown of Nrf2 using siRNA silencing technique significantly reversed the protective effects of I3C against Dex-induced apoptosis and ROS generation. Taken together, I3C can reverse cytotoxicity of Dex through blocking ROS overproduction and enhancement of Nrf2 expression. This study may provide a safe and good strategy for molecular intervention of GCs-induced osteoporosis by using natural products.

Platelet rich plasma enhanced neuro-regeneration of human dental pulp stem cells in vitro and in rat spinal cord.

Background: Human dental pulp stem cells (hDPSCs) exhibit excellent differentiation potential and are capable of differentiating into several different cellular phenotypes, including neurons. Platelet-rich plasma (PRP) contains numerous growth factors that can stimulate stem cell differentiation. In this study, we investigated the potential stimulatory effects of PRP on neurogenic differentiation and anti-apoptosis of hDPSCs in injured spinal cords. Methods: The unipotential differentiation capacity of hDPSCs was analyzed by cell surface antigen identification and cell cycle analysis. A spinal cord injury rat model composed of 40 Sprague-Dawley (SD) rats was used to facilitate an in vivo study. Rats were divided into four groups: a double-treatment group (receiving both neurogenic-induced hDPSCs and PRP), two single-treatment groups (receiving neurogenic-induced hDPSCs or PRP) and a sham group (receiving normal saline). The Basso, Beattie, Bresnahan Locomotor Rating Scale was subsequently used to evaluate the motor function of the spinal cord. Cell viability and differentiation of hDPSCs in the damaged spinal cords were analyzed and apoptosis of neural cells was evaluated using the terminal uridine nucleotide end labeling (TUNEL) assay. Results: Growth pattern, cell surface marker and cell cycle analyses revealed that hDPSCs have a high degree of multi-directional differentiation potential and can be induced into neurons in vitro. In the rat spinal cord injury model, double-treatment with hDPSC/PRP or single treatment with hDPSCs or PRP significantly improved motor function compared with the sham group (P<0.05). Apoptosis of neural cells was observed to be significantly higher in the sham group compared to any of the treatment groups. Double-treatment with hDPSCs and PRP resulted in the lowest apoptotic rate among the groups analyzed. Conclusions: hDPSCs exhibit differentiation potential and are capable of transforming into neural cells both in vitro and in vivo. Significantly increased inhibition of neuronal apoptosis and improved motor function recovery of the spinal cord were observed following double-treatment with hDPSCs and PRP compared with the single-treatment groups.

Protective effects of Dipsacus asper polysaccharide on osteoporosis in vivo by regulating RANKL/RANK/OPG/VEGF and PI3K/Akt/eNOS pathway.

A homogenous polysaccharide (DAP), with a molecular weight of 2.61 × 104 Da, was isolated from the roots of Dipsacus asper Wall. Gas chromatography (GC) indicated that DAP was composed of galactose and mannose with a molar ratio of 1:1. The purpose of this study was to evaluate the effect of DAP on the progress of bone loss in the ovariectomized (OVX) rat model of osteoporosis. Administration of DAP (50 and 200 mg/kg/body wt. day) for 12 weeks significantly prevented OVX-induced bone loss, biomechanical reduction, the body weight gain, the loss of the uterus weight, as well as increased U-Ca/Cr, U-P/Cr, ALP, TRAP, OC and DPD/Cr levels in rats, which was further supported by the histopathological examinations. Furthermore, we found that the mechanism by which DAP elicited anti-osteoporotic effects was mediated by up-regulation of VEGF and OPG, but down-regulation of RANK and RANKL in both protein and mRNA expression in OVX rats, as well as the activation of PI3K/Akt/eNOS signaling pathway, indicating that DAP can be clinically used as a potential alternative medicine for the prevention and treatment of postmenopausal osteoporosis.

Knockdown of lncRNA XIST suppresses osteosarcoma progression by inactivating AKT/mTOR signaling pathway by sponging miR-375-3p.

BACKGROUND: Osteosarcoma (OS) is one of the most common bone tumors in adolescents and young adults. Emerging evidence suggested ncRNA (lncRNA and miRNA) are closely associated with cell progression, apoptosis and autophagy. However, the role of regulatory network between ncRNA and mRNA in OS has not been fully verified. METHODS: lncRNA XIST, miRNA expression were detected by qRT-PCR. The protein expression of LC3, p62, AKT, p-AKT, mTOR and p-mTOR was measured by western blot. MTT assay and flow cytometry were applied to measure cell proliferation and apoptosis. Luciferase assay was used to ensure the relationship between lncRNA, miRNA and mRNA. GFP-LC3 cells were observed using fluorescence microscope. RESULTS: XIST expression was up-regulated but miR-375-3p was down-regulated in OS tissues and cells. Luciferase assay results demonstrated that miR-375-3p was a target of XIST and mTOR was a target mRNA of miR-375-3p. In addition, knockdown of XIST and mTOR inhibited OS cell proliferation and autophagy, but induced apoptosis. Knockdown of XIST could reverse the effect of miR-375-3p inhibitor on OS cells. The effects of si-mTOR of OS cells could be reversed by silencing miR-375-3p. Moreover, knockdown of XIST inhibited AKT/mTOR signaling pathway via sponging miR-375-3p. CONCLUSION: Knockdown of XIST inhibited cell growth and autophagy but induced cell apoptosis by suppressing the AKT/mTOR signaling pathway by sponging miR-375-3p.

Changes in bone mineral density and bone metabolic indexes in ankylosing spondylitis mouse model complicated with osteoporosis.

Changes in bone mineral density and bone metabolic indexes in a model of ankylosing spondylitis (AS) mice complicated with osteoporosis (OP) were investigated. BLAB/c mice were used as the subjects. AS was induced using proteoglycan, and OP was induced using tail suspension method. The mice were randomly divided into four groups: AS group, OP group, AS + OP group and negative control group. Changes in bone mineral density, bone strength, serum calcium (Ca), phosphorus, alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRACP), in mice of each group were detected and compared. There were statistically significant differences in bone mineral density and bone strength among groups. Compared with the negative control group, bone mineral density and bone strength in the AS, the OP and the AS + OP groups were significantly decreased, and the lowest bone mineral density and bone strength were found in the AS + OP group (P<0.05). There were no significant differences in bone mineral density and bone strength between the AS group and the OP group. Significant differences in serum Ca, ALP and TRACP but not in serum phosphorus were found among groups. Compared with the control group, serum levels of Ca and TRACP in the AS, the OP and the AS + OP groups were significantly increased, while levels of ALP were obviously decreased (P<0.05). Bone destruction in AS mice complicated with osteoarthritis was more serious than that in mice with simple AS.

Clindamycin Administration Increases the Incidence of Collagen-Induced Arthritis in Mice Through the Prolonged Impact of Gut Immunity.

The profound influence of gut flora on host immune system and its link with autoimmune disorders have been established. However, the role of certain antibiotic in progression of autoimmune disorder is still confusing. Here, we employed a collagen-induced arthritis (CIA) model to explore the role of clindamycin administration in different scenarios. In the first scenario, mice treated with antibiotics for 4 weeks were performed with the induction of CIA immediately. The results showed that clindamycin administration promoted the incidence and severity of CIA, while the recipients of vancomycin showed completed tolerance. We also found that increased gut-associated Th1 and Th17 cells might be related to the subsequent expansion of collagen-specific immune response. In the second scenario, mice treated with antibiotics for 4 weeks were performed with CIA induction 4 weeks later. Notably, clindamycin administration showed a prolonged impact on the incidence and severity of CIA, as well as the gut immunity as compared to vancomycin administration. In addition, antibody depletion of integrin α4ß7 systemically resulted in an impaired CIA response, underlining the influence of gut immunity. In the mice that received clindamycin, the abundance of anaerobic bacteria was significantly decreased and showed little recovery at 4 weeks later. Our observations highlighted the different characteristics of antibiotic administration on the development of autoimmune disorders and indicated its link with gut immunity.

[COMPARISON OF EFFECTIVENESS AND CHANGE OF SAGITTAL SPINO-PELVIC PARAMETERS BETWEEN MINIMALLY INVASIVE TRANSFORAMINAL AND CONVENTIONAL OPEN POSTERIOR LUMBAR INTERBODY FUSIONS IN TREATMENT OF LOW-DEGREE ISTHMIC LUMBAR SPONDYLOLISTHESIS].

OBJECTIVE: To compare the effectiveness and changes of sagittal spino-pelvic parameters between minimally invasive transforaminal lumbar interbody fusion and conventional open posterior lumbar interbody fusion in treatment of the low-degree isthmic lumbar spondylolisthesis. METHODS: Between May 2012 and May 2013, 86 patients with single segmental isthmic lumbar spondylolisthesis (Meyerding degree I or II) were treated by minimally invasive transforaminal lumbar interbody fusion (minimally invasive group) in 39 cases, and by open posterior lumbar interbody fusion in 47 cases (open group). There was no significant difference in gender, age, disease duration, degree of lumbar spondylolisthesis, preoperative visual analogue scale (VAS) score, and Oswestry disability index (ODI) between 2 groups (P>0.05). The following sagittal spino-pelvic parameters were compared between 2 groups before and after operation: the percentage of slipping (PS), intervertebral height, angle of slip (AS), thoracolumbar junction (TLJ), thoracic kyphosis (TK), lumbar lordosis (LL), sagittal vertical axis (SVA), spino-sacral angle (SSA), sacral slope (SS), pelvic tilt (PT), and pelvic incidence (PI). Pearson correlation analysis of the changes between pre- and post-operation was done. RESULTS: Primary healing of incision was obtained in all patients of 2 groups. The postoperative hospital stay of minimally invasive group [(5.1 ± 1.6) days] was significantly shorter than that of open group [(7.2 ± 2.1) days] (t = 2.593, P = 0.017). The patients were followed up 11-20 months (mean, 15 months). The reduction rate was 68.53% ± 20.52% in minimally invasive group, and was 64.21% ± 30.21% in open group, showing no significant difference (t = 0.725, P = 0.093). The back and leg pain VAS scores, and ODI at 3 months after operation were significantly reduced when compared with preoperative ones (P < 0.05), but no significant difference was found between 2 groups (P > 0.05). The postoperative other sagittal spino-pelvic parameters were significantly improved (P < 0.05) except PI (P > 0.05), but there was no significant difference between 2 groups (P > 0.05). The correlation analysis showed that ODI value was related to the SVA, SSA, PT, and LL (P < 0.05). CONCLUSION: Both minimally invasive transforaminal lumbar interbody fusion and conventional open posterior lumbar interbody fusion can significantly improve the sagittal spino-pelvic parameters in the treatment of low-degree isthmic lumbar spondylolisthesis. The reconstruction of SVA, SSA, PT, and LL are related to the quality of life.

Sulforaphane reverses glucocorticoid-induced apoptosis in osteoblastic cells through regulation of the Nrf2 pathway.

Apoptosis of osteoblasts triggered by high-dose glucocorticoids (GCs) has been identified as a major cause of osteoporosis. However, the underlying molecular mechanisms accounting for this action remain elusive, which has impeded the prevention and cure of this side effect. Sulforaphane (SFP) is a naturally occurring isothiocyanate that has huge health benefits for humans. In this study, by using osteoblastic MC3T3-E1 cells as a model, we demonstrate the protective effects of SFP against dexamethasone (Dex)-induced apoptosis and elucidate the underlying molecular mechanisms. The results show that SFP could effectively inhibit the Dex-induced growth inhibition and release of lactate dehydrogenase in MC3T3-E1 cells. Treatment with Dex induced caspase-dependent apoptosis in MC3T3-E1 cells, as evidenced by an increase in the Sub-G1 phase, chromatin condensation, and deoxyribonucleic acid fragmentation, which were significantly suppressed by coincubation with SFP. Mitochondria-mediated apoptosis pathway contributed importantly to Dex-induced apoptosis, as revealed by the activation of caspase-3/-9 and subsequent cleavage of poly adenosine diphosphate ribose polymerase, which was also effectively blocked by SFP. Moreover, treatments of Dex strongly induced overproduction of reactive oxygen species and inhibited the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and the downstream effectors HO1 and NQO1. However, cotreatment with SFP effectively reversed this action of Dex. Furthermore, silencing of Nrf2 by small interfering ribonucleic acid significantly blocked the cytoprotective effects of SFP against Dex-induced apoptosis, which suggest the important role of Nrf2 signaling pathway and cell apoptosis induced by Dex. Taken together, this study provides a novel strategy for molecular intervention against Dex-induced osteoporosis using phytochemicals.