The inflammatory cytokine TNF-α regulates the biological behavior of rat nucleus pulposus mesenchymal stem cells through the NF-κB signaling pathway in vitro.

Nucleus pulposus (NP) mesenchymal stem cells (NPMSCs) are a potential cell source for intervertebral disc (IVD) regeneration; however, little is known about their response to tumor necrosis factor-α (TNF-α), a critical inflammation factor contributing to accelerating IVD degeneration. Accordingly, the aim of this study was to investigate the regulatory effects of TNF-α at high and low concentrations on the biological behaviors of healthy rat NPMSCs, including proliferation, migration, and NP differentiation. In this study, NPMSCs were treated with different concentration of TNF-α (0-200 ng/mL). Then we used annexin V/propidium iodide flow cytometry analysis to detect the apoptosis rate of NPMSCs. Cell Counting Kit-8, Edu assay, and cell cycle test were used to examine the proliferation of NPMSCs. Migration ability of NPMSCs was detected by wound healing assay and transwell migration assay. Pellets method was used to induce NP differentiation of NPMSCs, and immunohistochemical staining, real-time polymerase chain reaction, and Western blot analysis were used to examine the NPC phenotypic genes and proteins. The cells were further treated with the nuclear factor-κB (NF-κB) pathway inhibitor Bay 11-7082 to determine the role of the NF-κB pathway in the mechanism underlying the differentiation process. Results showed that treatment with a high concentration of TNF-α (50-200 ng/mL) could induce apoptosis of NPMSCs, whereas a relatively low TNF-α concentration (0.1-10 ng/mL) promoted the proliferation and migration of NPMSCs, but inhibited their differentiation toward NP cells. Moreover, we identified that the NF-κB signaling pathway is activated during the TNF-α-inhibited differentiation of NPMSCs, and the NF-κB signal inhibitor Bay 11-7082 could partially eliminate the adverse effect of TNF-α on the differentiation of NPMSCs. Therefore, our findings provide important insight into the dynamic biological behavior reactivity of NPMSCs to TNF-α during IVD degeneration process, thus may help us understanding the underlying mechanism of IVD degeneration.

Baicalin Induces Apoptotic Death of Human Chondrosarcoma Cells through Mitochondrial Dysfunction and Downregulation of the PI3K/Akt/mTOR Pathway.

The aim of the present study was to investigate the cytotoxic and antitumour effects of baicalin in human chondrosarcoma both in vivo and in vitro. We examined the effects of baicalin on the growth and apoptosis of human chondrosarcoma cells. Baicalin inhibited the growth of SW1353 and CH2879 cells in a dose- and time-dependent manner, but did not inhibit the growth of normal chondrocytes. Baicalin reduced tumour growth and induced apoptotic death in SW1353-transplanted nude mice without reducing their body weight. Further studies showed that baicalin reduced the mitochondrial membrane potential, upregulated the expression of Bax and cytoplasmic cytochrome c, downregulated the expression of Bcl-2 and mitochondrial cytochromes, and activated caspase-3 and caspase-9. Baicalin inhibited the phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin pathway by decreasing the expression of phosphorylated phosphoinositide 3-kinase, phosphorylated protein kinase B, and phosphorylated mammalian target of rapamycin both in vivo and in vitro. Moreover, the mice that received SC79 and baicalin exhibited a greater tumour size compared with the mice that received baicalin. The mice that received LY294002 and baicalin showed a smaller tumour size compared with the mice that received baicalin. In the in vitro study, SC79 and LY294002 affected the baicalin-induced cytotoxic effects on chondrosarcoma cells in the same manner. Our data suggest baicalin has therapeutic efficacy in human chondrosarcoma through the induction of apoptosis and inhibition of the phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin pathway. Baicalin can be considered a potential therapeutic agent for treating chondrosarcomas.

Radiographic analysis of the correlation between ossification of the nuchal ligament and sagittal alignment and segmental stability of the cervical spine in patients with cervical spondylotic myelopathy.

BACKGROUND: Ossification of the nuchal ligament (ONL) caused by chronic injury to the nuchal ligament (NL) is very common in instability-related cervical disorders. PURPOSE: To determine possible correlations between ONL, sagittal alignment, and segmental stability of the cervical spine. MATERIAL AND METHODS: Seventy-three patients with cervical spondylotic myelopathy (CSM) and ONL (ONL group) and 118 patients with CSM only (control group) were recruited. Radiographic data included the characteristics of ONL, sagittal alignment and segmental stability, and ossification of the posterior longitudinal ligament (OPLL). We performed comparisons in terms of radiographic parameters between the ONL and control groups. The correlations between ONL size, cervical sagittal alignment, and segmental stability were analyzed. Multivariate logistic regression was used to identify the independent risk factors of the development of ONL. RESULTS: C2-C7 sagittal vertical axis (SVA), T1 slope (T1S), T1S minus cervical lordosis (T1S-CL) on the lateral plain, angular displacement (AD), and horizontal displacement (HD) on the dynamic radiograph increased significantly in the ONL group compared with the control group. The size of ONL significantly correlated with C2-C7 SVA, T1S, AD, and HD. The incidence of ONL was higher in patients with OPLL and segmental instability. Cervical instability, sagittal malalignment, and OPLL were independent predictors of the development of ONL through multivariate analysis. CONCLUSION: Patients with ONL are more likely to have abnormal sagittal alignment and instability of the cervical spine. Thus, increased awareness and appreciation of this often-overlooked radiographic finding is warranted during diagnosis and treatment of instability-related cervical pathologies and injuries.

The Contribution of Diffusion Tensor Imaging to Quantitative Assessment on Multilevel Cervical Spondylotic Myelopathy.

BACKGROUND/AIMS: This study aimed at assessing the feasibility of diffusion tensor imaging (DTI) in multilevel cervical spondylotic myelopathy (MCSM) and quantifying the association between DTI parameters and neuronal status as a whole. METHODS: Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were obtained from 32 patients with MCSM and 21 healthy volunteers at each level. The extent of cervical cord compression was evaluated by maximum spinal cord compression (MSCC). The DTI parameters were correlated with myelopathy severity based on modified Japanese Orthopedic Association (mJOA) score in comparison with anatomic morphological and signal changes on MRI. RESULTS: There were significant differences in the DTI values between the patients and those in the control group (p < 0.001). The general mean FA values correlated with mJOA scores strongly (r = 0.507, p = 0.003), even more than MSCC (r = -0.361, p = 0.042); however, such an association was not detected between ADC values and clinical findings (p > 0.05). CONCLUSION: DTI shows a higher potential to quantitatively evaluate the whole neurological deficits of patients with MCSM. It helps us better understand the minor pathological changes within the spinal cord at an earlier stage than abnormal signal changes on MRI.

Development and validation of a nomogram to predict the risk of surgical site infection within 1 month after transforaminal lumbar interbody fusion.

OBJECTIVE: Surgical site infection (SSI), a common serious complication within 1 month after transforaminal lumbar interbody fusion (TLIF), usually leads to poor prognosis and even death. The objective of this study is to investigate the factors related to SSI within 1 month after TLIF. We have developed a dynamic nomogram to change treatment or prevent infection based on accurate predictions. MATERIALS AND METHODS: We retrospectively analyzed 383 patients who received TLIF at our institution from January 1, 2019, to June 30, 2022. The outcome variable in the current study was the occurrence of SSI within 1 month after surgery. Univariate logistic regression analysis was first performed to assess risk factors for SSI within 1 month after surgery, followed by inclusion of significant variables at P < 0.05 in multivariate logistic regression analysis. The independent risk variables were subsequently utilized to build a nomogram model. The consistency index (C-index), calibration curve and receiver operating characteristic curve were used to evaluate the performance of the model. And the decision curve analysis (DCA) was used to analyze the clinical value of the nomogram. RESULTS: The multivariate logistic regression models further screened for three independent influences on the occurrence of SSI after TLIF, including lumbar paraspinal (multifidus and erector spinae) muscles (LPM) fat infiltration, diabetes and surgery duration. Based on the three independent factors, a nomogram prediction model was built. The area under the curve for the nomogram including these predictors was 0.929 in both the training and validation samples. Both the training and validation samples had high levels of agreement on the calibration curves, and the nomograms C-index was 0.929 and 0.955, respectively. DCA showed that if the threshold probability was less than 0.74, it was beneficial to use this nomograph to predict the risk of SSI after TLIF. In addition, the nomogram was converted to a web-based calculator that provides a graphical representation of the probability of SSI occurring within 1 month after TLIF. CONCLUSION: A nomogram including LPM fat infiltration, surgery duration and diabetes is a promising model for predicting the risk of SSI within 1 month after TLIF. This nomogram assists clinicians in stratifying patients, hence boosting decision-making based on evidence and personalizing the best appropriate treatment.

MCP­1/CCR2 axis inhibits the chondrogenic differentiation of human nucleus pulposus mesenchymal stem cells.

Intervertebral disc degeneration (IDD) creates a hostile environment with high osmotic pressure, high mechanical stress, hypoxia and a low pH, where cytokines such as TNF­α and IL­1ß are highly expressed. The degenerating intervertebral disc has high local expression of monocyte chemoattractant protein­1 (MCP­1), which is associated with the degree of degeneration. However, there are a few reports on the influence of MCP­1 on nucleus pulposus­derived stem cells (NPSCs). In the present study, a significant upregulation of MCP­1 was observed in NPSCs cultured in vitro with pro­inflammatory cytokines. MCP­1 significantly inhibited the migration and proliferation of NPSCs in a dose­dependent manner as detected via Cell Counting Kit­8, wound healing and Transwell assays. Western blotting and histological analysis demonstrated that MCP­1 significantly reduced chondrogenic NPSC differentiation. Reverse transcription­quantitative PCR and western blotting revealed that C­C chemokine receptor type 2 (CCR2) mRNA and protein expression levels were significantly enhanced by MCP­1. Furthermore, MCP­1 significantly inhibited the migration, differentiation and proliferation of NPSCs, which was effectively reversed by blocking CCR2 with the inhibitor RS504393. Overall, these results demonstrated that MCP­1 may contribute to the inhibition of chondrogenic NPSC differentiation via MCP­1/CCR2 chemotaxis signals, providing a potential therapeutic target for IDD.

The Role of Unfolded Protein Response in Human Intervertebral Disc Degeneration: Perk and IRE1-α as Two Potential Therapeutic Targets.

Inflammation plays a key role in intervertebral disc degeneration (IDD). The association between inflammation and endoplasmic reticulum (ER) stress has been observed in many diseases. However, whether ER stress plays an important role in IDD remains unclear. Therefore, this study is aimed at investigating the expression of ER stress in IDD and at exploring the underlying mechanisms of IDD, ER stress, and inflammation. The expression of ER stress was activated in nucleus pulposus cells from patients who had IDD (D-NPCs) compared with patients without IDD (N-NPCs); and both the proliferation and synthesis capacity were decreased by inducer tunicamycin (Tm) and proinflammatory cytokines. Pretreatment of NPCs with 4-phenyl butyric acid (4-PBA) prevented the inflammatory cytokine-induced upregulation of unfolded protein response- (UPR-) related proteins and recovered cell synthetic ability. Furthermore, proinflammatory cytokine treatment significantly upregulated the expression of inositol-requiring protein 1 (IRE1-α) and protein kinase RNA-like ER kinase (PERK), but not activating transcription factor 6 (ATF6). Finally, knockdown of IRE1-α and PERK also restored the biological activity of NPCs. Our findings identified that IRE1-α and PERK might be the potential targets for IDD treatment, which may help illustrate the underlying mechanism of ER stress in IDD.

Development and validation of a nomogram predicting the risk of recurrent lumbar disk herniation within 6 months after percutaneous endoscopic lumbar discectomy.

OBJECTIVE: To develop and validate a nomogram useful in predicting recurrent lumbar disk herniation (rLDH) within 6 months after percutaneous endoscopic lumbar discectomy (PELD). METHODS: Information on patients' lumbar disk herniation (LDH) between January 2018 and May 2019 in addition to 26 other features was collected from the authors' hospital. The least absolute shrinkage and selection operator (LASSO) method was used to select the most important risk factors. Moreover, a nomogram was used to build a prediction model using the risk factors selected from LASSO regression. The concordance index (C-index), the receiver operating characteristic (ROC) curve, and calibration curve were used to assess the performance of the model. Finally, clinical usefulness of the nomogram was analyzed using the decision curve and bootstrapping used for internal validation. RESULTS: Totally, 352 LDH patients were included into this study. Thirty-two patients had recurrence within 6 months while 320 showed no recurrence. Four potential factors, the course of disease, Pfirrmann grade, Modic change, and migration grade, were selected according to the LASSO regression model. Additionally, the C-index of the prediction nomogram was 0.813 (95% CI, 0.726-0.900) and the area under receiver operating characteristic curve (AUC) value was 0.798 while the interval bootstrapping validation C-index was 0.743. Hence, the nomogram might be a good predictive model. CONCLUSION: Each variable, the course of disease, Pfirrmann grade, Modic change, and migration grade in the nomogram had a quantitatively corresponding risk score, which can be used in predicting the overall recurrence rate of rLDH within 6 months.

Early Clinical Outcomes of Percutaneous Endoscopic Lumbar Discectomy for L4-5 Highly Down-Migrated Disc Herniation: Interlaminar Approach Versus Transforaminal Approach.

OBJECTIVE: This study is a retrospective evaluation of patients with L4-5 highly down-migrated lumbar disc herniation (LDH) operated with interlaminar endoscopic lumbar discectomy (IELD) versus transforaminal endoscopic lumbar discectomy (TELD). METHODS: From January 2015 to December 2018, 77 patients with L4-5 highly down-migrated LDH were divided into 2 groups according to different surgical approaches. There were 40 patients who underwent IELD, and 37 patients who underwent TELD. The operation time, hospital stay, Oswestry Disability Index, clinical outcome according with modified MacNab criteria, Visual Analog Scale (VAS) scores, and complications were compared between the IELD and TELD groups. RESULTS: Seventy-seven patients were included, 40 and 37 patients underwent IELD and TELD, respectively. The IELD and TELD groups both achieved a significant improvement in Oswestry Disability Index, back and leg VAS scores, and clinical outcome postoperation. Mean operating and x-ray times during operation were significantly shorter in the IELD group than in the TELD group (41.8 vs. 50.3, 1.8 vs. 13.7). There were 3 patients who experienced recurrence in the IELD group and 2 in the TELD group. In the TELD group, there were 3 patients who required revision surgery due to incompletely removed disc fragment. All patients in the IELD group were treated successfully. There was no other complication in these cases. CONCLUSIONS: Both IELD and TELD could be a good alternative option for highly down-migrated LDH in L4-L5. IELD may have advantages in operation time and x-ray times during operation compared with TELD.

Activation of SIRT1 promotes cartilage differentiation and reduces apoptosis of nucleus pulposus mesenchymal stem cells via the MCP1/CCR2 axis in subjects with intervertebral disc degeneration.

Intervertebral disc degeneration (IDD) is a condition involving disruption of the bone tissue distribution. Nucleus pulposus mesenchymal stem cells (NPMSCs) and Sirtuin 1 (SIRT1) play important roles in bone diseases, therefore the aim of the present study was to evaluate the roles of SIRT1 and NPMSCs in IDD. First, NPMSCs were harvested from patients with IDD. Then, the NPMSCs were treated with a SIRT activator, and monocyte chemoattractant protein 1 (MCP1) and chemokine receptor 2 (CCR2) inhibitors. Indices related to NPMSC growth, proliferation, differentiation and apoptosis were measured. Subsequently, IDD rat models were established and were transfected with NPMSCs overexpressing SIRT1. NPMSC apoptosis and cartilage differentiation were detected in the rat IDD model. SIRT1 expression was found to be decreased, and the expression of MCP1 and CCR2 increased in NPMSCs of patients with IDD. The upregulation of SIRT1 and the downregulation of the MCP1/CCR2 axis promoted cartilage differentiation and reduced the number of apoptotic NPMSCs. Furthermore, MCP1 reversed the progression of the cartilage differentiation of NPMSCs and the inhibition of NPMSC apoptosis induced by SIRT1 overexpression. Moreover, the transplantation of rat NPMSCs overexpressing SIRT1 relieved IDD in rats. Therefore, SIRT1 overexpression improved cartilage differentiation and reduced the apoptosis of NPMSCs by inactivating the MCP1/CCR2 axis, thus attenuating IDD in rats.

RhTSG-6 inhibits IL-1ß-induced extracellular matrix degradation and apoptosis by suppressing the p38, and JNK pathways in nucleus pulposus cells.

INTRODUCTION: Intervertebral disc degeneration (IDD) is one of the major causes of low back pain (LBP) which seriously affects health and normal physical activity. Recombinant human tumor necrosis factor-a (TNF-a) induced protein 6 (rhTSG-6) has been reported to have therapeutic effects on a variety of inflammatory diseases, but the effect and mechanism of rhTSG-6 action in IDD are not fully understood. The present study was aimed to explore the functional role of rhTSG-6 in interleukin (IL)-1b-induced nucleus pulposus (NP) cell model. MATERIALS AND METHODS: Experimental human NP cells were isolated from the patients with idiopathic scoliosis and treated with culture medium containing IL-1b (10 ng/mL) for 24 hours to induce extracellular matrix degradation and apoptosis, simulating an IDD model in vitro. The viability of NP cells was analyzed by the CCK-8 assay. The relevant mRNA and protein levels were measured by RT-qPCR and western blot. The apoptosis of NP cells was determined by flow cytometry analysis and western blot. RESULTS: Compared with the NP cells without IL-1b treatment, IL-1b caused approximately 70% reduction in the viability of NP cells, while RhTSG-6 partly increased the decrease of IL-1b on cell viabilities. Moreover, treatment with rhTSG-6 considerably attenuated the upregulation of extracellular matrix (ECM)-catabolic factors (MMP-3, MMP-13, ADAMTS-4, and ADAMTS-5), and increased the downregulation of ECM-anabolic factor (collagen II) in NP cells induced by IL-1b, indicating that ECM degradation was suppressed. Furthermore, rhTSG-6 also protected NP cells from IL-1b-induced apoptosis. Mechanically, rhTSG-6 inhibited the activation of members of mitogen-activated protein kinase (MAPK) pathway by blocking the phosphorylation of p38, c-Jun N-terminal kinase (JNK) and ERK in IL-1b-induced NP cells. CONCLUSIONS: RhTSG-6 can attenuate ECM degradation and apoptosis in IL-1b-induced NP cells by inhibiting the p38, JNK and ERK pathways, which may contribute to its potential application in the therapy of IDD.

Nomogram for predicting kyphotic deformity after laminoplasty in cervical spondylotic myelopathy patients without preoperative kyphotic alignment.

BACKGROUND: Kyphotic deformity occurrence after cervical laminoplasty is not rare. Several studies have emphasized the development of postoperative kyphotic deformity (PKD) will impair the functional outcome of cervical laminoplasty. We established and validated a nomogram prediction model for kyphotic deformity after laminoplasty in cervical spondylotic myelopathy patients (CSM) without preoperative kyphotic alignment. METHODS: Preoperative and 1-year postoperative data of 369 patients who underwent single-door cervical laminoplasty (SDCL) at the author's hospital between July 2010 and February 2018 were collected. Using the least absolute shrinkage and selection operator (LASSO) method, significant parameters were selected to develop a nomogram prediction model. The prognostic performance of the model was evaluated using concordance index (C-index) and calibration curve. The discriminatory ability of the prediction model was evaluated by the area under (receiver operating characteristic) curve (AUC). RESULTS: Of the 369 patients, 31 developed PKD in 1 year after the surgery. Using the LASSO regression, six significant variables composed the final model: age, C2-7 sagittal vertical axis, C7 slope, C2-7 angle, flexion range of motion and operation level were selected. The AUC of the nomogram was 0.771. The C-index for the prediction nomogram was 0.771 (95 % CI: 0.672-0.870). The calibration curve also indicated good consistency. CONCLUSION: A nomogram for predicting PKD after SDCL was established and validated. For patients evaluated by this model with predictive high risk of developing postoperative kyphosis, an alternative approach to the subaxial cervical spine such as anterior surgery should be considered.

Successful Bony Healing For An Adult Patient With Isthmic Spondylolysis At Terminal Stage After Conservative Treatment: A Case Report.

PURPOSE: Spondylolysis, a defect or fracture of the pars interarticularis due to mechanical stress, is a common cause of lower back pain (LBP) in children and adolescents. Although conservative treatment has been shown to be most effective for young patients at early or progressive stage, few studies have reported the outcomes of conservative treatment for adult spondylolysis at terminal stage. We present the possibility of bony healing in the isthmic defect at terminal stage after conservative treatment. PATIENTS AND METHODS: A 50-year-old male patient complaining of moderate LBP was diagnosed as having L5 bilateral pars defect accompanied with related grade I spondylolisthesis though radiological evaluation. Magnetic resonance imaging revealed the sclerotic change in the defect of the isthmus, indicating spondylolysis at the terminal stage. This patient was treated with conservative management including lower back muscle functional exercises and medication when necessary. RESULTS: After five years of follow-up, the patient had a good recovery without reoccurrence. The repeated radiography and computed tomography demonstrated the pars defect had disappeared and been replaced by trabeculation, with no evidence of progressive segmental instability or vertebrae slip. CONCLUSION: Symptomatic adult patients with isthmus spondylolysis at terminal stage might still have an opportunity to be effectively managed with rigorous conservative treatment for obtaining bony healing. However, the progression of listhesis or persistent debilitating pain should warrant consideration for surgical treatment.

Effects of Stromal Cell-Derived Factor-1α Secreted in Degenerative Intervertebral Disc on Activation and Recruitment of Nucleus Pulposus-Derived Stem Cells.

Stromal cell-derived factor-1α (SDF-1α) plays a significant role in mobilizing and recruiting mesenchymal stem cells (MSCs) to the sites of injury. This study investigated the potential of SDF-1α released in the degenerative intervertebral disc (IVD) to activate and recruit endogenous nucleus pulposus-derived stem cells (NPSCs) for regeneration in situ. We found SDF-1α was highly expressed and secreted by the native disc cells when cultured in the proinflammatory mediators in vitro mimicking the degenerative settings. Immunohistochemical staining also showed that the expression level of SDF-1α was significantly higher in the degenerative group compared to that in the normal group. In addition to enhancement of viability, SDF-1α significantly increased the number of NPSCs migrating into the center of the nucleotomized bovine IVD ex vivo. After the systemic delivery of exogenous PKH26-labelled NPSCs into the rats in vivo, there was a significant difference in the distribution of the migrated cells between the normal and the degenerative IVDs, which might be caused by the different expression levels of SDF-1α. However, blocking CXC chemokine receptor 4 (CXCR4) with AMD3100 effectively abrogated SDF-1α-stimulated proliferation and migration. Taken together, SDF-1α may be a key chemoattractant that is highly produced in response to the degenerative changes, which can be used to enhance the proliferation and recruitment of endogenous stem cells into the IVDs. These findings may be of importance for understanding IVD regenerative mechanisms and development of regenerative strategies in situ for IVD degeneration.

Stromal cell-derived factor-1α promotes recruitment and differentiation of nucleus pulposus-derived stem cells.

BACKGROUND: Intervertebral disc (IVD) degeneration is a condition characterized by a reduction in the water and extracellular matrix content of the nucleus pulposus (NP) and is considered as one of the dominating contributing factors to low back pain. Recent evidence suggests that stromal cell-derived factor 1α (SDF-1α) and its receptor C-X-C chemokine receptor type 4 (CXCR4) direct the migration of stem cells associated with injury repair in different musculoskeletal tissues. AIM: To investigate the effects of SDF-1α on recruitment and chondrogenic differentiation of nucleus pulposus-derived stem cells (NPSCs). METHODS: We performed real-time RT-PCR and enzyme-linked immunosorbent assay to examine the expression of SDF-1α in nucleus pulposus cells after treatment with pro-inflammatory cytokines in vitro. An animal model of IVD degeneration was established using annular fibrosus puncture in rat coccygeal discs. Tissue samples were collected from normal control and degeneration groups. Differences in the expression of SDF-1α between the normal and degenerative IVDs were analyzed by immunohistochemistry. The migration capacity of NPSCs induced by SDF-1α was evaluated using wound healing and transwell migration assays. To determine the effect of SDF-1α on chondrogenic differentiation of NPSCs, we conducted cell micromass culture and examined the expression levels of Sox-9, aggrecan, and collagen II. Moreover, the roles of SDF-1/CXCR4 axis in the migration and chondrogenesis differentiation of NPSCs were analyzed by immunofluorescence, immunoblotting, and real-time RT-PCR. RESULTS: SDF-1α was significantly upregulated in the native IVD cells cultured in vitro with pro-inflammatory cytokines, such as interleukin-1ß and tumor necrosis factor-α, mimicking the degenerative settings. Immunohistochemical staining showed that the level of SDF-1α was also significantly higher in the degenerative group than in the normal group. SDF-1α enhanced the migration capacity of NPSCs in a dose-dependent manner. In addition, SDF-1α induced chondrogenic differentiation of NPSCs, as evidenced by the increased expression of chondrogenic markers using histological and immunoblotting analyses. Real-time RT-PCR, immunoblotting, and immunofluorescence showed that SDF-1α not only increased CXCR4 expression but also stimulated translocation of CXCR4 from the cytoplasm to membrane, accompanied by cytoskeletal rearrangement. Furthermore, blocking CXCR4 with AMD3100 effectively suppressed the SDF-1α-induced migration and differentiation capacities of NPSCs. CONCLUSION: These findings demonstrate that SDF-1α has the potential to enhance recruitment and chondrogenic differentiation of NPSCs via SDF-1/CXCR4 chemotaxis signals that contribute to IVD regeneration.

Evaluation of intervertebral disc regeneration with injection of mesenchymal stem cells encapsulated in PEGDA-microcryogel delivery system using quantitative T2 mapping: a study in canines.

Intervertebral disc degeneration (IDD), the primary cause of low back pain, is still a great challenge to spinal surgeons and clinicians. T2 mapping, a biochemical magnetic resonance imaging (MRI) technique to calculate relaxation time, has the potential to offer a quantitative assessment of IDD. The aim of the study was to evaluate the regenerative effects of adipose-derived mesenchymal stem cells (MSCs) encapsulated in PEGDA-microcryogels (PMs) reinforced alginate hydrogel (AH) on the degenerative intervertebral disc (IVD) in a canine model using T2 mapping. Four degeneration-induced IVDs (L3-L4 to L6-L7) of 12 adult beagle dogs were injected with phosphate-buffered saline (PBS), MSCs, AH-PMs, and MSCs-laden AH-PMs, respectively. The intact IVD L7-S1 served as the normal control. IVD height change on plain radiograph, Pfirrmann grade and T2 relaxation time on MRI, histological change, and extracellular matrix (ECM)-associated proteins were evaluated during the 24-week follow-up period. Injection of MSCs-laden AH-PMs had the most satisfactory effects, having less decrease of IVD height, lower Pfirrmann grade, milder histological change, and longer T2 relaxation time (P < 0.05). T2 relaxation time was positively correlated with ECM content (proteoglycan: r = 0.85, P < 0.001; collagen II: r = 0.79, P < 0.001) and IVD height (r = 0.81, P < 0.001), but negatively correlated with Pfirrmann grade and histological grade (rho = -0.86, P < 0.001; rho = -0.95, P < 0.001). These results suggest that T2 mapping has the potential to quantitatively evaluate the repairing effects of cell-based engineering treatments on IDD for a long-term follow-up.

Successful Conservative Management of Delayed Cervical Spondylodiscitis with Epidural Abscess Caused by Esophageal Diverticulitis: A Case Report and Review of Literature.

BACKGROUND: Cervical spondylodiscitis with spinal epidural abscess (SEA) is not a rare medical condition and usually requires urgent decompression of neural structures and stabilization of the spine followed by antibiotic therapy for the prevention of severe neurologic deficits. CASE DESCRIPTION: In this report, we present a 43-year-old male patient with the chief complaint of neck pain and intermittent fever accompanying by slight dysphagia. After 2 weeks, he felt mild and transient numbness on the left upper limb. He had a history of esophageal intervention under endoscopy. Magnetic resonance imaging disclosed diffuse hyperintensity in the left paraesophageal and prevertebral tissues and a space-occupying lesion within the spinal canal. The esophagography revealed a saclike barium collection parallel to the upper esophagus herniating out from the posterior wall without evident leakage. Neither surgical decompression nor drainage was chosen by this patient; conservative treatment with antibiotic administration was managed to achieve a good neurologic recovery and remarkable resolution of the epidural abscess. During antibiotic therapy and dietary restriction, the symptoms of diverticulitis was also managed expectantly. CONCLUSIONS: Physicians need to be aware of this rare case of SEA secondary to esophageal diverticulitis. An early diagnosis and prompt administration of antibiotics is a key factor to avoid neurologic deterioration for the treatment of SEA caused by diverticulitis. Endoscopic or surgical repair of diverticulum may be warranted to avoid the recurrence of such infection.

ß-Escin inhibits the proliferation of osteosarcoma cells via blocking the PI3K/Akt pathway.

ß-Escin exhibits anticancer effects on a panel of established cancer cells. However, the effects of ß-escin on human osteosarcoma (OS) are still unknown. The aim of the present study was to investigate whether ß-escin was effective against OS both in vivo and in vitro. Our results showed that ß-escin induced dose- and time-dependent effects against MG-63, OS732, U-2OS, HOS and SAOS-2 cell proliferation. ß-Escin also exhibited excellent anti-proliferative and pro-apoptotic effects in an established OS xenograft model. ß-Escin and cytotoxic drugs, including cisplatin, methotrexate (MTX), doxorubicin (Dox) and ifosfamide (Ifos), synergistically inhibited proliferation of MG-63 and OS732 cells in vitro. Moreover, ß-escin induced apoptotic death, activated caspase-3, caspase-8 and caspase-9, and regulated expression of Bax and Bcl-2 in MG-63 cells. In addition, our results showed that ß-escin treatment reduced expression of p-PI3K, p-Akt and p-mTOR both in MG-63 cells and in an MG-63 xenograft OS model. Interestingly, SC79, which is an Akt activator, inhibited the anti-proliferative effects of ß-escin on MG-63 cells. Taken together, our data support the conclusion that ß-escin effectively inhibits OS proliferation both in vivo and in vitro. The inhibitory effect of ß-escin, at least in part, is due to the inactivation of the PI3K/Akt signalling pathway.

Roles of Cell Cyle Regulators Cyclin D1, CDK4, and p53 in Knee Osteoarthritis.

OBJECTIVE: The aim of this study was to investigate the roles of cyclin D1, CDK4, and p53 in knee osteoarthritis (KOA). METHODS: A total of 76 healthy controls and 154 KOA cases (grades ranging from II to IV) were recruited. Protein expression of cyclin D1, CDK4, and p53 were detected by immunohistochemistry, and mRNA expression levels of the cyclin D1, the CDK4, and the p53 genes were measured by reverse transcription-polymerase chain reaction. RESULTS: Both protein and mRNA expression levels of cyclin D1 and CDK4 were significantly lower in KOA cases than those in healthy controls, while protein and mRNA expression of p53 was significantly higher in KOA cases than that in healthy controls (all p < 0.05). As the grades of KOA increased, Cyclin D1 and CDK4 mRNA expressions decreased, whereas p53 mRNA expression increased (all p < 0.05). In KOA cases, mRNA expression of Cyclin D1 was positively correlated to CDK4 mRNA levels (r = 0.386, p < 0.001), while negatively correlated with p53 mRNA levels (r = -0.227, p = 0.005). CONCLUSIONS: Expression of the Cyclin D1, CDK4, and p53 genes are correlated with the disease grades of KOA.