[Small tidal volume hyperventilation relieves intraocular and intracranial pressure elevation in prone spinal surgery: a randomized controlled trial]

OBJECTIVE

To investigate the effects of different ventilation strategies on intraocular pressure (IOP) and intracranial pressure in patients undergoing spinal surgery in the prone position under general anesthesia.

METHODS

Seventy-two patients undergoing prone spinal surgery under general anesthesia between November, 2022 and June, 2023 were equally randomized into two groups to receive routine ventilation (with Vt of 8mL/kg, Fr of 12-15/min, and etCO2 maintained at 35-40 mmHg) or small tidal volume hyperventilation (Vt of 6 mL/kg, Fr of18-20/min, and etCO2 maintained at 30-35 mmHg) during the surgery. IOP of both eyes (measured with a handheld tonometer), optic nerve sheath diameter (ONSD; measured at 3 mm behind the eyeball with bedside real-time ultrasound), circulatory and respiratory parameters of the patients were recorded before anesthesia (T0), immediately after anesthesia induction (T1), immediately after prone positioning (T2), at 2 h during operation (T3), immediately after supine positioning after surgery (T4) and 30 min after the operation (T5).

RESULTS

Compared with those at T1, IOP and ONSD in both groups increased significantly at T3 and T4(P < 0.05). IOP was significantly lower in hyperventilation group than in routine ventilation group at T3 and T4(P < 0.05), and ONSD was significantly lower in hyperventilation group at T4(P < 0.05). IOP was positively correlated with the length of operative time (r=0.779, P < 0.001) and inversely with intraoperative etCO2 at T3(r=-0.248, P < 0.001) and T4(r=-0.251, P < 0.001).ONSD was correlated only with operation time (r=0.561, P < 0.05) and not with IOP (r=0.178, P>0.05 at T3; r=0.165, P>0.05 at T4).

CONCLUSION

Small tidal volume hyperventilation can relieve the increase of IOP and ONSD during prone spinal surgery under general anesthesia.

Maslinic acid alleviates intervertebral disc degeneration by inhibiting the PI3K/AKT and NF-κB signaling pathways

Intervertebral disc degeneration (IDD) is the cause of low back pain (LBP), and recent research has suggested that inflammatory cytokines play a significant role in this process. Maslinic acid (MA), a natural compound found in olive plants ( Olea europaea), has anti-inflammatory properties, but its potential for treating IDD is unclear. The current study aims to investigate the effects of MA on TNFα-induced IDD in vitro and in other in vivo models. Our findings suggest that MA ameliorates the imbalance of the extracellular matrix (ECM) and mitigates senescence by upregulating aggrecan and collagen II levels as well as downregulating MMP and ADAMTS levels in nucleus pulposus cells (NPCs). It can also impede the progression of IDD in rats. We further find that MA significantly affects the PI3K/AKT and NF-κB pathways in TNFα-induced NPCs determined by RNA-seq and experimental verification, while the AKT agonist Sc-79 eliminates these signaling cascades. Furthermore, molecular docking simulation shows that MA directly binds to PI3K. Dysfunction of the PI3K/AKT pathway and ECM metabolism has also been confirmed in clinical specimens of degenerated nucleus pulposus. This study demonstrates that MA may hold promise as a therapeutic agent for alleviating ECM metabolism disorders and senescence to treat IDD.

Comparing perioperative outcomes between regional anesthesia and general anesthesia in patients undergoing hip fracture surgery: a systematic review and meta-analysis

PURPOSE

Nearly all patients with hip fractures undergo surgical treatment. The use of different anesthesia techniques during surgery may influence the clinical outcomes. The optimal anesthetic technique for patients undergoing hip fracture surgery is still controversial. We performed this updated systematic review and meta-analysis to compare clinical outcomes of patients undergoing hip fracture surgery with different anesthesia techniques.

SOURCE

Articles published from 2000 to May 2023 were included from MEDLINE, Embase, Web of Science, and the Cochrane Library. We included randomized controlled trials and observational studies comparing general anesthesia (GA) with regional anesthesia (RA) for the outcomes of 30-day mortality, 90-day mortality, in-hospital mortality, perioperative complications, length of hospital stay, and length of surgery in patients undergoing hip fracture surgery. Subgroup analyses were performed for the outcomes based on study design (randomized controlled trials or observational studies). We used a random-effects model for all analyses.

PRINCIPAL FINDINGS

In this meta-analysis, we included 12 randomized controlled trials. There was no difference in postoperative 30-day mortality between the two groups (odds ratio [OR], 0.88; 95% confidence interval [CI], 0.44 to 1.74; I2 = 0%). The incidence of intraoperative hypotension was lower in patients who received RA vs GA (OR, 0.52; 95% CI, 0.38 to 0.72; I2 = 0%). No significant differences were observed in 90-day mortality, in-hospital mortality, postoperative delirium, pneumonia, myocardial infarction, venous thromboembolism, length of surgery, and length of hospital stay.

CONCLUSION

In this updated systematic review and meta-analysis, RA did not reduce postoperative 30-day mortality in hip fracture surgery patients compared to GA. Fewer patients receiving RA had intraoperative hypotension than those receiving GA did. Apart from intraoperative hypotension, the data showed no differences in complications between the two anesthetic techniques.

STUDY REGISTRATION

PROSPERO (CRD42023411854); registered 7 April 2023.

Behavioral, metabolic, and lipidomic characterization of the 5xFADxTg30 mouse model of Alzheimer's disease

Alzheimer's disease (AD) is associated with both extracellular amyloid-β (Aβ) plaques and intracellular tau-containing neurofibrillary tangles (NFT). We characterized the behavioral, metabolic and lipidomic phenotype of the 5xFADxTg30 mouse model which contains overexpression of both Aβ and tau. Our results independently reproduce several phenotypic traits described previously for this model, while providing additional characterization. This model develops many aspects associated with AD including frailty, decreased survival, initiation of aspects of cognitive decline and alterations to specific lipid classes and molecular lipid species in the plasma and brain. Notably, some sex-specific differences exist in this model and motor impairment with aging in this model does compromise the utility of the model for some movement-based behavioral assessments of cognitive function. These findings provide a reference for individuals interested in using this model to understand the pathology associated with elevated Aβ and tau or for testing potential therapeutics for the treatment of AD.

Facet joint tropism, pelvic incidence and intervertebral height index: associations with facet joint osteoarthritis in lumbar spinal stenosis

BACKGROUND CONTEXT

Facet joint osteoarthritis (FJOA) is associated with lumbar disc degeneration and has a significant role in the development of lumbar spinal stenosis (LSS). The relationship between various radiographic parameters and the grade of FJOA is not well understood.

PURPOSE

To explore radiographical parameters associated with FJOA in LSS without lumbar dynamic instability.

STUDY DESIGN

Retrospective study analysis.

PATIENT SAMPLE

A total of 122 patients diagnosed with LSS who visited our hospital between January 2015 and July 2022.

OUTCOME MEASURES

We evaluated radiographic parameters of patients at L4-5 including lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), grades of FJOA, facet joint orientation (FO), facet joint tropism (FT), intervertebral height index (IHI) and the relative cross-sectional area (RCSA) of paraspinal muscles.

METHODS

Patients diagnosed with LSS between January 2015 and July 2022 were enrolled. Demographic characteristics and radiographic parameters were collected. Spinopelvic parameters were measured through the preoperative lateral image of the whole spine, including LL, PI, pelvic tilt, and sacral slope. Lumbar computed tomography scan and magnetic resonance imaging were collected to measure the FO, FT, IHI, and the RCSA of paraspinal muscles respectively. Patients were divided into three groups according to the severity of FJOA graded by the Weishaupt classification: grade 0 and grade 1 were group A, grade 2 were group B, and grade 3 were group C. All variables were compared among the three groups, while the relationship between parameters and grades of FJOA were also analyzed.

RESULTS

A total of 122 patients were included. PI was significantly greater in group C compared to group A (p = 0.025) and group B (p=0.022). FT was significantly greater in group C compared to group A (p<.001) and group B (p<.001). The RCSA of multifidus in group A were significantly greater than that in group B (p=0.02) and C (p=0.002). Additionally, FO in group C were significantly lower than group A (p<.001) and group B (p=0.028). The IHI in group C was significantly lower than group A (p=0.017). The correlation analysis indicated that grades of FJOA was positively related to Age, BMI (body mass index), PI, LL and FT, while negatively related to IHI, FO, RCSA of multifidus and RCSA of psoas major. Furthermore, the logistics regression showed that FT, PI, and IHI were important influence factors for FJOA.

CONCLUSIONS

The current study confirmed that FT, PI and IHI were significantly associated with grades of FJOA at L4-5. Additionally, longitudinal studies are needed to understand the causal relationship between these parameters and FJOA.

Correlation analysis of surgical outcomes and spino-pelvic parameters in patients with degenerative lumbar scoliosis

Objectives

The study aims to analyze factors that affect the postoperative health-related quality of life (HRQOL) of degenerative lumbar scoliosis (DLS) patients and explore the appropriate pelvic incidence minus lumbar lordosis (PI-LL) value for Chinese DLS patients.

Methods

DLS patients who met the inclusion and exclusion criteria were included in this study. General information, spino-pelvic parameters, and HRQOL were collected. Correlation analysis was used to explore the spino-pelvic parameters that affect the postoperative HRQOL. Thresholds of each parameter were obtained using the receiver operating characteristic (ROC) curve. Regardless of the effect of age, DLS patients were classified into three groups according to the SRS-Schwab classification: group 0 means PI-LL < 10°, group+means PI-LL = 10-20°, and group ++ means PI-LL > 20°. Postoperative HRQOL was analyzed using variance methods. The ROC curve was used to measure the appropriate PI-LL threshold. When considering the effect of age, the patients with Oswestry Disability Index (ODI) < 75% percentile were considered to have a satisfactory clinical outcome, which was drawn to an equation between PI-LL, age, and PI by multiple linear regression equation.

Results

A total of 71 patients were included. Compared with the control group, there were significant differences in both postoperative ODI and Scoliosis Research Society 22 (SRS-22) scores when the postoperative Cobb angle ≤11°, postoperative lumbar lordosis index (LLI) > 0.8, postoperative sagittal vertical axis (SVA) ≤ 5 cm, postoperative T1 pelvic angle (TPA) ≤ 16° and postoperative global tilt (GT) ≤ 22°, respectively. Regardless of the effect of age, there was a statistical difference in postoperative HRQOL between group 0 and group ++. The PI-LL threshold derived from the ROC curve was 14.4°. Compared with the PI-LL > 14° group, the PI-LL ≤ 14° group achieved a lower postoperative ODI score and a higher postoperative SRS-22 score. Considering the influence of age, the equation for ideal PI-LL was PI-LL = 0.52age + 0.38PI-39.4 (R = 0.509, p = 0.001).

Conclusions

PI-LL was an important parameter that affects the postoperative HRQOL of DLS patients. Sufficient LL should be restored during the operation (LL ≥ PI-14°). The appropriate PI-LL value was affected by age. Smaller LL needed to be restored as the age increased.

YTHDF1 Enhances Chondrogenic Differentiation by Activating the Wnt/β-Catenin Signaling Pathway

Cartilage is derived from the chondrogenic differentiation of stem cells, for which the regulatory mechanism has not been fully elucidated. N6-methyladenosine (m6A) messenger RNA (mRNA) methylation is the most common posttranscriptional modification in eukaryotic mRNAs and is mediated by m6A regulators. However, whether m6A regulators play roles in chondrogenic differentiation is unknown. Herein, we aim to determine the role of a main m6A reader protein, YTH N6-methyladenosine RNA binding protein 1 (YTHDF1), in chondrogenic differentiation regulation. Western blotting (WB) assays found that the expression of YTHDF1 increased during chondrogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs). The results of quantitative polymerase chain reaction, WB, immunohistochemistry, and Alcian blue staining revealed that overexpression of YTHDF1 increased cartilage matrix synthesis and the expression of chondrogenic markers when hBMSCs, ATDC5 cells, or C3H10T1/2 cells were induced to undergo chondrogenesis. Conversely, chondrogenesis was clearly inhibited when YTHDF1 was knocked down in hBMSCs, ATDC5 cells, or C3H10T1/2 cells. Further RNA sequencing and molecular biology experiments found that YTHDF1 activated the Wnt/β-catenin signaling pathway during chondrogenic differentiation. Finally, the effects of overexpression and knockdown of YTHDF1 on chondrogenic differentiation were reversed by inhibiting or activating β-catenin activity. Therefore, we demonstrated that YTDHF1 promoted chondrogenic differentiation through activation of the Wnt/β-catenin signaling pathway.

Current research progress of local drug delivery systems based on biodegradable polymers in treating chronic osteomyelitis

Chronic osteomyelitis is one of the most challenging diseases in orthopedic treatment. It is usually treated with intravenous antibiotics and debridement in clinical practice, which also brings systemic drug side effects and bone defects. The local drug delivery system of antibiotics has the characteristics of targeted slow release to the lesion site, replacing systemic antibiotics and reducing the toxic and side effects of drugs. It can also increase the local drug concentration, achieve sound bacteriostatic effects, and promote bone healing and formation. Currently, PMMA beads are used in treating chronic osteomyelitis at home and abroad, but the chain beads need to be removed after a second operation, inconveniences patients. Biodegradable materials have been extensively studied as optimal options for antibiotic encapsulation and delivery, bringing new hope for treating chronic osteomyelitis. This article reviews the research progress of local drug delivery systems based on biodegradable polymers, including natural and synthetic ones, in treating chronic osteomyelitis.

Identifying the key genes regulating mesenchymal stem cells chondrogenic differentiation: an in vitro study

Background

Mesenchymal stem cells (MSCs) possess the potential to differentiate into chondrocytes, which makes them an ideal source for healing cartilage defects. Here, we seek to identify the essential genes participating in MSCs chondrogenesis.

Methods

Human MSCs were induced for chondrogenesis for 7, 14, and 21 days using a high-density micromass culture system, and RNA was extracted for RNA-seq.

Results

A total of 6247 differentially expressed genes (DEGs) were identified on day 7, and 85 DEGs were identified on day 14. However, no significant DEGs was identified on day 21. The top 30 DEGs at day 7, including COL9A3, COL10A1, and CILP2, are closely related to extracellular matrix organization. While the top 30 DEGs at day 14 revealed that inflammation-related genes were enriched, including CXCL8, TLR2, and CCL20. We also conducted protein–protein interaction (PPI) networks analysis using the search tool for the retrieval of interacting genes (STRING) database and identified key hub genes, including CXCL8, TLR2, CCL20, and MMP3. The transcriptional factors were also analyzed, identifying the top 5 TFs: LEF1, FOXO1, RORA, BHLHE41, and SOX5. We demonstrated one particular TF, RORA, in promoting early MSCs chondrogenesis.

Conclusions

Taken together, our results suggested that these DEGs may have a complex effect on MSCs chondrogenesis both synergistically and solitarily.

Evaluating bone quality and asymmetrical aplasia of the thoracic vertebral body in Lenke 1A adolescent idiopathic scoliosis using hounsfield units

Study Design

Retrospective analysis.

Objective

To evaluate bone quality and investigate asymmetrical development of the thoracic vertebral body in adolescent idiopathic scoliosis (AIS) based on Hounsfield unit (HU) measurements obtained from computed-tomography (CT) scans.

Summary of Background Data

HU value demonstrated higher reliability and accuracy than the traditional method, indicating that they could be used to individually evaluate and effectively assess the bone quality of every vertebra in the CT films.

Methods

Total 30 AIS patients classified as Lenke Type 1A and 30 paired controls were included in this study. Regions of interest for HU value were measured on three horizontal images of the thoracic vertebrae. HU measurements of the whole vertebral body in each vertebra were obtained. Using HU value, we separately measured the concave and convex sides of each vertebral body in patients' group, as well as within the left and right sides in controls.

Results

In controls, the mean HU value of T1–T12 thoracic vertebral bodies was 240.03 ± 39.77, with no statistical differences among different levels. As for AIS patients, in the structural curve, the apical region had a significantly lower HU compared with the other regions, and asymmetrical change was found between the concave and convex sides, most significantly in the apical region. In the non-structural curve, the average HU value was 254.99 ± 44.48, and no significant difference was found either among the different levels of vertebrae or between the concave and convex sides.

Conclusions

Abnormal and asymmetrical changes in bone quality of the thoracic vertebral body in patients with Lenke 1A AIS were indicated. Low bone quality in the convex side of the structural curve indicated stronger internal fixation in surgery to correct the deformity.

Irisin enhances chondrogenic differentiation of human mesenchymal stem cells via Rap1/PI3K/AKT axis

Background

Human mesenchymal stem cells (hMSCs) have been proven to have inherent chondrogenic differentiation potential, which appears to be used in cartilage regeneration. Increasing evidence suggests that irisin enhances osteoblast differentiation of MSCs, but little is known about its potential on chondrogenic differentiation.

Methods

In the study, we investigated the effects of irisin on chondrogenic differentiation of hMSCs using a high-density pellet culture system. The cartilage pellets were evaluated by morphology, and the metabolism of cartilage matrix was detected by qPCR, western blot and immunohistochemistry. Next, RNA-seq was performed to explore the underlying mechanism. Furthermore, using the transduction of plasmid, miRNAs mimics and inhibitor, the activation of Rap1/PI3K/AKT axis, the expression level of SIPA1L2, and the functional verification of miR-125b-5p were detected on day 7 of chondrogenic differentiation of hMSCs.

Results

Compared with the controls, we found that irisin treatment could significantly enhance the chondrogenic differentiation of hMSCs, enlarge the induced-cartilage tissue and up-regulate the expression levels of cartilage markers. RNA-seq indicated that irisin activated the Rap1 and PI3K/AKT signaling pathway, and the lower expression level of SIPA1L2 and the higher expression level of miR-125b-5p were found in irisin-treated group. Further, we found that irisin treatment could up-regulate the expression level of miR-125b-5p, targeting SIPA1L2 and consequently activating the Rap1/PI3K/AKT axis on the process of chondrogenic differentiation of hMSCs.

Conclusions

Collectively, our study reveals that irisin can enhance chondrogenic differentiation of hMSCs via the Rap1/PI3K/AKT pathway, suggesting that irisin possesses prospects in cartilage regeneration.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-03092-8.

Comparison of anterior or posterior approach in surgical treatment of thoracic and lumbar tuberculosis: a retrospective case-control study

BACKGROUND

With the widespread use of the posterior surgery, more and more surgeons chose posterior surgery to treat thoracic and lumbar tuberculosis. But others still believed that the anterior surgery is more conducive to eradicating the lesions, and easier to place larger bone pieces for bone graft fusion. We compared the clinical and radiological outcomes of anterior and posterior surgical approaches and presented our views.

METHODS

This study included 52 thoracic and lumbar tuberculosis patients at Sun Yat-sen Memorial Hospital from January 2010 to June 2018. All cases underwent radical debridement, nerve decompression, intervertebral bone graft fusion and internal fixation. Cases were divided into anterior group (24 cases) and posterior group (28 cases). Statistical analysis was used to compare the clinical effectiveness, radiological outcomes, complications and other related information.

RESULTS

Patients in the anterior group and the posterior group were followed up for an average of 27.4 and 22.3 months, respectively. There were no statistically significant differences between groups in the preoperative, postoperative and last follow-up VAS score, ASIA grade and Cobb angle of local kyphosis. Moreover, there were no statistically significant differences in the improvement of neurological function, loss of kyphotic correction, total incidence of complications, operative time, intraoperative blood loss and hospital stay between the two groups (P > 0.05). But there was greater correction of kyphosis, earlier bone fusion, lower incidence of poor wound healing, less interference with the normal spine and less internal fixation consumables and medical cost in the anterior group (P < 0.05).

CONCLUSIONS

Both anterior and posterior approaches are feasible for thoracic and lumbar tuberculosis. While for thoracic and lumbar tuberculosis patients with a single lesion limited in the anterior and middle columns of the spine without severe kyphosis, the anterior approach surgery may have greater advantages in kyphosis correction, bone fusion, wound healing, protection of the normal spine, and medical consumables and cost.

Efficacy Evaluation of Ciprofloxacin-Loaded Poly (Trimethylene Carbonate) Implants in the Treatment of Chronic Osteomyelitis

In this study, poly (trimethylene carbonate) (PTMC) with excellent biocompatibility was synthesized via ring-opening of TMC to prepare the Ciprofloxacin-loaded PTMC implants, and antibacterial effects in vitro or in vivo of the resulting implants were investigated to evaluate the potential for treating chronic osteomyelitis. The in vitro results showed the Ciprofloxacin-loaded PTMC implants could sustain release ciprofloxacin at a release amount of about 90 μg/d for 28 days and possessed excellent antibacterial effect, as evidenced by the smaller size of the antibacterial ring of 32.6 ± 0.64 mm and the biofilm inhibition of 60% after 28 days of release. The in vivo results showed that after 28 days of treatment, the body weight and the white blood cell counts of chronic-osteomyelitis-model rats in the treatment group reached 381.6 ± 16.8 g and (7.86 ± 0.91) ×10⁹/L, respectively, returning to normal rapidly compared with the control and blank group, indicating the remarkable antibacterial effect of the Ciprofloxacin-loaded PTMC implants. X-ray images and HE staining results also confirmed that most of the proximal and middle parts of the tibia returned to typical structures and new and trabecular bone had been formed for the rats in the treatment group, and no inflammatory cells were found as compared to the control and blank groups, after 28 days of treatment. The significant lower number of colonies of (9.92 ± 1.56) × 10 CFU/g in the treatment group also suggests that the Ciprofloxacin-loaded PTMC implants achieve a practical antibacterial effect through a local application.

Monoclinic-triclinic phase transition induced by pressure in fergusonite-type YbNbO4

We have carried out a high-pressure study on monoclinic fergusonite-type YbNbO₄. Synchrotron powder x-ray diffraction experiments and density-functional theory simulations have been performed. We found a gradual increase of symmetry under compression, with calculations predicting a second-order monoclinic-tetragonal transition at 15 GPa. However, experiments provided evidence of a transition at 11.6 GPa to a triclinic structure, described by space groupP1¯. The appearance of the triclinic phase, which according to calculations is dynamically unstable under hydrostatic conditions, seems to be related to the presence of non-hydrostatic stresses. The triclinic high-pressure phase remains stable up to 31.9 GPa and the phase transition is not reversible. We have determined the pressure dependence of unit-cell parameters of both phases and calculated their room-temperature equation of state. For the fergusonite-phase we have also obtained the isothermal compressibility tensor. In addition to the high-pressure studies, we report ambient-pressure Raman and infrared spectroscopy measurements which have been compared with density-functional theory calculations.

Melatonin reverses tumor necrosis factor-alpha-induced metabolic disturbance of human nucleus pulposus cells via MTNR1B/Gαi2/YAP signaling

Background: Intervertebral disc degeneration (IDD), the main cause of low back pain, is closely related to the inflammatory microenvironment in the nucleus pulposus (NP). Tumor necrosis factor-α (TNF-α) plays an important role in inflammation-related metabolic disturbance of NP cells. Melatonin has been proven to regulate the metabolism of NP cells, but whether it can protect NP cells from TNF-α-induced damage is still unclear. Therefore, this study aims to investigate the role and specific mechanism of melatonin on regulating the metabolism of NP cells in the inflammatory microenvironment.

Methods: Western blotting, RT-qPCR and immunohistochemistry were used to detect the expression of melatonin membrane receptors (MTNR1A/B) and TNF-α in human NP tissues. In vitro, human primary NP cells were treated with or without vehicle, TNF-α and melatonin. And the metabolic markers were also detected by western blotting and RT-qPCR. The activity of NF-κB signaling and Hippo/YAP signaling were assessed by western blotting and immunofluorescence. Membrane receptors inhibitors, pathway inhibitors, lentiviral infection, plasmids transfection and immunoprecipitation were used to explore the specific mechanism of melatonin. In vivo, the rat IDD model was constructed and melatonin was injected intraperitoneally to evaluate its therapeutical effect on IDD.

Results: The upregulation of TNF-α and downregulation of melatonin membrane receptors (MTNR1A/B) were observed in degenerative NP tissues. Then we demonstrated that melatonin could alleviate the development of IDD in a rat model and reverse TNF-α-impaired metabolism of NP cells in vitro. Further investigation revealed that the protective effects of melatonin on NP cells mainly rely on MTNR1B, which subsequently activates Gαi2 protein. The activation of Gαi2 could upregulate the yes-associated protein (YAP) level, resulting in anabolic enhancement of NP cells. In addition, melatonin-mediated YAP upregulation increased the expression of IκBα and suppressed the TNF-α-induced activation of the NF-κB pathway, thereby inhibiting the catabolism of NP cells.

Conclusions: Our results revealed that melatonin can reverse TNF-α-impaired metabolism of NP cells via the MTNR1B/Gαi2/YAP axis and suggested that melatonin can be used as a potential therapeutic drug in the treatment of IDD.

Inhibition of nuclear receptor RORα attenuates cartilage damage in osteoarthritis by modulating IL-6/STAT3 pathway

Osteoarthritis (OA) is characterized by cartilage destruction, chronic inflammation, and local pain. Evidence showed that retinoic acid receptor-related orphan receptor-α (RORα) is crucial in cartilage development and OA pathogenesis. Here, we investigated the role and molecular mechanism of RORα, an important member of the nuclear receptor family, in regulating the development of OA pathologic features. Investigation into clinical cartilage specimens showed that RORα expression level is positively correlated with the severity of OA and cartilage damage. In an in vivo OA model induced by anterior crucial ligament transaction, intra-articular injection of si-Rora adenovirus reversed the cartilage damage. The expression of cartilage matrix components type II collagen and aggrecan were elevated upon RORα blockade. RNA-seq data suggested that the IL-6/STAT3 pathway is significantly downregulated, manifesting the reduced expression level of both IL-6 and phosphorylated STAT3. RORα exerted its effect on IL-6/STAT3 signaling in two different ways, including interaction with STAT3 and IL-6 promoter. Taken together, our findings indicated the pivotal role of the RORα/IL-6/STAT3 axis in OA progression and confirmed that RORα blockade improved the matrix catabolism in OA chondrocytes. These results may provide a potential treatment target in OA therapy.

Identification of key potential targets for TNF-α/TNFR1-related intervertebral disc degeneration by bioinformatics analysis

BACKGROUND

Bioinformatics analysis was performed on gene expression profile microarray data to identify the key genes activated through the TNF-α/TNFR1 signaling pathway in intervertebral disc degeneration (IDD). The common differentially expressed genes (co-DEGs) were calculated in nucleus pulposus (NP) cells and annulus fibrosus (AF) cells under TNF-α treatment or TNFR1 knockdown, which reveals the potential mechanism of TNF-α involvement in IDD and may provide new therapeutic targets for IDD.

METHODS

Differentially expressed genes (DEGs) in TNF-α-treated or TNFR1-knockdown NP cells and AF cells were identified. Further analysis of the gene ontology (GO), signaling pathways and interaction networks of the DEGs or co-DEGs were conducted using the Database for Annotation, Visualization and Integrated Discovery, STRING Database, and Cytoscape software. The relationship between genes and musculoskeletal diseases, including IDD, was assessed with the Comparative Toxicogenomics Database. The predicted microRNAs corresponding to the co-DEGs were also identified by microRNA Data Integration Portal.

RESULTS

In NP cells, the DEGs (|log₂FoldChange|>2, adj.P < 0.01) were identified including 48 DEGs by TNF-α treatment and 74 DEGs by TNFR1 knockdown; in AF cells, correspondingly, 105 DEGs were identified. The co-DEGs between NP cells and AF cells were calculated including CXCL8, ICAM1, BIRC3, RELB, NFKBIA, and TNFAIP3. They may be the hub genes that were significantly associated with both NP cells and AF cells through the TNF-α/TNFR1 signaling pathway. The co-DEGs and corresponding predicted miRNAs may be potential therapeutic targets for IDD.

CONCLUSIONS

CXCL8, ICAM1, BIRC3, RELB, NFKBIA, and TNFAIP3 may have a synergistic effect on TNF-α-induced IDD development.Abbreviations: IDD: Intervertebral disc degeneration; NP: Nucleus pulposus; AF: Annulus fibrosus; co-DEG: Common differentially expressed gene; GO: Gene Ontology; KEGG: Kyoto Encyclopedia of Genes and Genomes; PPI: Protein-protein interaction.

Melatonin promotes bone marrow mesenchymal stem cell osteogenic differentiation and prevents osteoporosis development through modulating circ_0003865 that sponges miR-3653-3p

Background

Little is known about the implications of circRNAs in the effects of melatonin (MEL) on bone marrow mesenchymal stem cell (BMSC) osteogenic differentiation and osteoporosis (OP) progression. The aim of our study was to investigate circRNAs in MEL-regulated BMSC differentiation and OP progression.

Methods

BMSC osteogenic differentiation was measured by qRT-PCR, western blot (WB), Alizarin Red, and alkaline phosphatase (ALP) staining. Differential circRNA and mRNA profiles of BMSCs treated by MEL were characterized by deep sequencing, followed by validation using RT-PCR, Sanger sequencing, and qRT-PCR. Silencing and overexpression of circ_0003865 were conducted for functional investigations. The sponged microRNAs and targeted mRNAs were predicted by bioinformatics and validated by qRT-PCR, RNA pull-down, and dual-luciferase reporter assay. The function of miR-3653-3p and circ_0003865/miR-3653-3p/growth arrest-specific gene 1 (GAS1) cascade was validated for the osteogenic differentiation of BMSCs by CCK-8, qRT-PCR, WB, Alizarin Red, and ALP staining. The effects of circ_0003865 on OP development were tested in murine OP model.

Results

MEL promoted osteogenic differentiation of BMSCs. RNA sequencing revealed significant alterations in circRNA and mRNA profiles associated with multiple biological processes and signaling pathways. Circ_0003865 expression in BMSCs was significantly decreased by MEL treatment. Silencing of circ_0003865 had no effect on proliferation while promoted osteogenic differentiation of BMSCs. Overexpression of circ_0003865 abrogated the promotion of BMSC osteogenic differentiation induced by MEL, but proliferation of BMSCs induced by MEL had no change whether circ_0003865 was overexpression or not. Furthermore, circ_0003865 sponged miR-3653-3p to promote GAS1 expression in BMSCs. BMSC osteogenic differentiation was enhanced by miR-3653-3p overexpression while BMSC proliferation was not affected. By contrast, miR-3653-3p silencing mitigated the promoted BMSC osteogenic differentiation caused by circ_0003865 silencing, but had no effect on proliferation. Finally, circ_0003865 silencing repressed OP development in mouse model.

Conclusion

MEL promotes BMSC osteogenic differentiation and inhibits OP pathogenesis by suppressing the expression of circ_0003865, which regulates GAS1 gene expression via sponging miR-3653-3p.

Bromodomain-containing protein 4 inhibition alleviates matrix degradation by enhancing autophagy and suppressing NLRP3 inflammasome activity in NP cells

An imbalance between matrix synthesis and degradation is the hallmark of intervertebral disc degeneration while inflammatory cytokines contribute to the imbalance. Bromodomain and extra-terminal domain (BET) family is associated with the pathogenesis of inflammation, and inhibition of BRD4, a vital member of BET family, plays an anti-inflammatory role in many diseases. However, it remains elusive whether BRD4 plays a similar role in nucleus pulposus (NP) cells and participates in the pathogenesis of intervertebral disc degeneration. The present study aims to observe whether BRD4 inhibition regulates matrix metabolism by controlling autophagy and NLRP3 inflammasome activity. Besides, the relationship was investigated among nuclear factor κB (NF-κB) signaling, autophagy and NLRP3 inflammasome in NP cells. Here, real-time polymerase chain reaction, western blot analysis and adenoviral GFP-LC3 vector transduction in vitro were used, and it was revealed that BRD4 inhibition alleviated the matrix degradation and increased autophagy in the presence or absence of tumor necrosis factor α. Moreover, p65 knockdown or treatment with JQ1 and Bay11-7082 demonstrated that BRD4 inhibition attenuated NLRP3 inflammasome activity through NF-κB signaling, while autophagy inhibition by bafilomycin A1 promoted matrix degradation and NLRP3 inflammasome activity in NP cells. In addition, analysis of BRD4 messenger RNA expression in human NP tissues further verified the destructive function of BRD4. Simply, BRD4 inhibition alleviates matrix degradation by enhancing autophagy and suppressing NLRP3 inflammasome activity through NF-κB signaling in NP cells.

Erdheim-Chester disease mimicking lumbar nerve schwannoma: case report and literature review

Introduction

Erdheim-Chester disease (ECD) is a rare, non-Langerhans cell histiocytosis. The clinical spectrum of ECD is diverse, varying from asymptomatic focal lesion to life-threatening multisystem infiltration. Neurological manifestations of ECD are common, mostly due to the involvement of the central nerve system. However, spinal nerve or peripheral nerve involvement has rarely been mentioned.

Case presentation

Herein, we present a case of a 32-year-old female patient complaining about radiating pain on the front and lateral side of her left thigh for 2 months. Spinal MRI with contrast enhancement showed a space-occupying lesion on the left L3/L4 intervertebral foramen, indicating an initial diagnosis of lumbar nerve schwannoma. The patient underwent surgery to remove the mass and decompress the lumbar nerve. Postoperative histological examination revealed the diffuse infiltration of foamy histiocytes that were CD68+, CD163+, and CD1a- on immunostaining, which confirmed the diagnosis of Erdheim-Chester disease. The radiating pain was gradually alleviated and PET-CT was performed but showed no further involvement of ECD.

Discussion

To the best of our knowledge, this is the first case of ECD demonstrated as an infiltrative mass on the spinal nerve, with imaging manifestations and compression symptoms similar to those of peripheral nerve schwannoma.

Association between the ABO blood group and primary knee osteoarthritis: A case-control study

Background

Recent studies have suggested association between the ABO blood group and inflammation, which was a crucial pathological process of primary knee osteoarthritis. The aim of this study was to investigate the association between the ABO blood group and primary knee osteoarthritis ​and the severity of primary knee osteoarthritis evaluated by the Kellgren/Lawrence score, as well as the histopathologic association in a subgroup of patients.

Methods

We performed a retrospective review of patients with primary knee osteoarthritis that served as the case group ​and a random sampling of healthy blood donors that served as the control group. The severity of knee osteoarthritis at the first outpatient visit was evaluated by the Kellgren/Lawrence scoring system. Further study was performed to investigate the expression of blood group antigens in synovial tissue of the knee in both cases and controls.

Results

A total of 1126 cases and 30299 controls were involved. The proportion of AB blood group was higher in the case group than in the control group (9.7% vs. 7.8%), and logistic regression revealed that the AB blood group was a risk factor of primary knee osteoarthritis (P ​= ​0.025 and 0.048 for univariate and multivariate analysis, respectively), independent of age (P ​= ​0.973) and sex (P ​= ​0.520). Patients of the blood group AB had a higher Kellgren/Lawrence score (P ​= ​0.017). The immunohistochemical study indicated association between Le^Y antigen and primary knee osteoarthritis (P ​= ​0.029).

Conclusions

This study suggested that the blood group AB was associated with primary knee osteoarthritis, as well as its radiological severity. Further study indicated that Le^Y antigen, which was related to the blood group, was associated with primary knee osteoarthritis.

Translational potential of this article

This study revealed that blood group AB and Le^Y antigen was associated with primary knee osteoarthritis, which shed new light on the nature of osteoarthritis, and the development of novel therapy for osteoarthritis.

Melatonin prevents bone destruction in mice with retinoic acid-induced osteoporosis

BACKGROUND

The protective effect of melatonin against bone metabolism imbalance in osteoporosis (OP) induced by drugs such as retinoic acid (RA) is unclear. The aim of this study was to explore the role of melatonin in bone destruction based on a mouse model.

METHODS

RA-induced OP model mice were established. To assess the effect of melatonin on these mice, micro-CT was used to characterize the trabecular structure of normal mice and those treated with RA (model), RA + low-dose melatonin (Mlt-L), RA + high-dose melatonin (Mlt-H), and RA + alendronate sodium (positive control). The shape of the trabecular bone, the length and diameter of the femoral head and the height and diameter of vertebra(L1) of each group were also measured and the number of osteoclasts was determined by Tartrate-resistant acid phosphatase (TRACP) staining. Meanwhile, the expression of alkaline phosphatase (ALP) was evaluated by immunohistochemistry assays. The differences between groups in terms of liver and kidney oxidation-related indexes and serum and urinary indicators related to bone metabolism were also analyzed. Furthermore, qRT-PCR and western blotting were used to evaluate the effect of melatonin on osteogenic and osteoclastic differentiation in MC3T3-E1 and RAW264.7 cells, respectively.

RESULTS

RA induction led to a decrease in the amount and density of trabecular bone, a decrease in the length and diameter of the femur and height, diameter of the vertebra (L1), a decrease in bone mass and density and the expression of ALP, and an increase in the number of osteoclasts. Melatonin treatment alleviated these effects induced by RA, increasing the amount of trabecular bone in OP mice, improving the microstructure of the femur and vertebra(L1) and increasing bone mass bone density and the expression of ALP, as well as decreasing the number of osteoclasts. Additionally, blood and urinary bone metabolism-related indicators showed that melatonin promoted bone formation and inhibited bone resorption. Determination of oxidant and antioxidant biomarkers in the livers and kidneys of the mice revealed that melatonin promoted the antioxidant level and suppressed the level of oxidant molecules in these organs. In vitro, RA promoted osteoclasts and inhibit osteogenesis by increasing oxidative stress levels in the RAW264.7 and MC3T3-E1 cells, but melatonin reversed this effect. Melatonin may, therefore, play a role in the ERK/SMAD and NF-κB pathways.

CONCLUSIONS

Melatonin can alleviate bone loss in RA-induced OP model mice, repair the trabecular microstructure, and promote bone formation. These effects may be related to reducing oxidation levels in vivo and vitro through the ERK/SMAD and NF-κB pathways.

Collagen type II suppresses articular chondrocyte hypertrophy and osteoarthritis progression by promoting integrin β1-SMAD1 interaction

Hypertrophic differentiation is not only the terminal process of endochondral ossification in the growth plate but is also an important pathological change in osteoarthritic cartilage. Collagen type II (COL2A1) was previously considered to be only a structural component of the cartilage matrix, but recently, it has been revealed to be an extracellular signaling molecule that can significantly suppress chondrocyte hypertrophy. However, the mechanisms by which COL2A1 regulates hypertrophic differentiation remain unclear. In our study, a Col2a1 p.Gly1170Ser mutant mouse model was constructed, and Col2a1 loss was demonstrated in homozygotes. Loss of Col2a1 was found to accelerate chondrocyte hypertrophy through the bone morphogenetic protein (BMP)-SMAD1 pathway. Upon interacting with COL2A1, integrin β1 (ITGB1), the major receptor for COL2A1, competed with BMP receptors for binding to SMAD1 and then inhibited SMAD1 activation and nuclear import. COL2A1 could also activate ITGB1-induced ERK1/2 phosphorylation and, through ERK1/2-SMAD1 interaction, it further repressed SMAD1 activation, thus inhibiting BMP-SMAD1-mediated chondrocyte hypertrophy. Moreover, COL2A1 expression was downregulated, while chondrocyte hypertrophic markers and BMP-SMAD1 signaling activity were upregulated in degenerative human articular cartilage. Our study reveals novel mechanisms for the inhibition of chondrocyte hypertrophy by COL2A1 and suggests that the degradation and decrease in COL2A1 might initiate and promote osteoarthritis progression.

A signaling feedback loop that contributes to cartilage degeneration may offer a fruitful target for the treatment of osteoarthritis. During the early stages of this disorder, cartilage-forming chondrocytes undergo a process of expansion known as hypertrophy, after which they die and are replaced by calcium. Researchers led by Peiqiang Su and Dongsheng Huang of Sun Yat-sen University have demonstrated that COL2A1, an important structural protein, represents an important safeguard against hypertrophy. COL2A1 helps maintain chondrocytes in their normal, healthy state, but Su and Huang showed that signaling factors produced during cartilage repair can reduce COL2A1 levels. This in turn accelerates hypertrophy, promoting further depletion of COL2A1 and ultimately leading to full-blown osteoarthritis. Drugs that break this cycle and preserve COL2A1 could thus help protect endangered joints before the damage becomes severe.

MicroRNA-155 suppresses the catabolic effect induced by TNF-α and IL-1β by targeting C/EBPβ in rat nucleus pulposus cells

AIM

miR-155 is a pro-inflammatory or anti-inflammatory factor depending on the cell type in which it is expressed. miR-155 controls apoptosis and matrix degradation in nucleus pulposus (NP) cells in vitro. The aim of this study is to explore the effect of miR-155 in vivo and further investigate the mechanism of miR-155 in vitro.

METHODS

MRI, hematoxylin-eosin staining, or Collagen-II immunochemistry were performed to observe intervertebral disk degeneration in conditional miR-155 overexpression mice and miR-155 knockout mice. In vitro, a dual luciferase reporter assay, real-time PCR and western blot experiments were performed to demonstrate the effect of miR-155 on the expression of catabolic genes induced by inflammatory cytokines and determine the role of β-catenin and C/EBPβ in the miR-155-mediated modulation of the expression of catabolic genes.

RESULTS

Degeneration was observed in the lumbar disks of 1-year-old miR-155 knockout mice but not in the conditional miR-155 overexpression mice. miR-155 overexpression repressed the catabolic effect induced by TNF-α or IL-1β in vitro. Furthermore, specifically in NP cells, miR-155 overexpression suppressed the expression of C/EBPβ but not of β-catenin. Additionally, in the loss-of-function experiments using C/EBPβ siRNA, C/EBPβ knockdown repressed the expression of catabolic genes induced by TNF-α and IL-1β, which is consistent with the miR-155 results.

CONCLUSION

miR-155 is a sustainable factor for intervertebral disk and suppresses the expression of catabolic genes induced by TNF-α and IL-1β by targeting C/EBPβ in rat NP cells.

Melatonin-mediated miR-526b-3p and miR-590-5p upregulation promotes chondrogenic differentiation of human mesenchymal stem cells

Bone marrow-derived mesenchymal stem cells (BMSCs), with inherent chondrogenic differentiation potential appear to be ideally suited for therapeutic use in cartilage regeneration. Accumulating evidence has demonstrated that melatonin can promote chondrogenic differentiation in human BMSCs. However, little is known about the mechanism. MicroRNAs (miRNAs) have been shown to regulate the differentiation of BMSCs, but their roles in melatonin-promoted chondrogenic differentiation have not been characterized. Here, we demonstrate that melatonin promoted chondrogenic differentiation of human BMSCs via upregulation of miR-526b-3p and miR-590-5p. Mechanistically, the elevated miR-526b-3p and miR-590-5p enhanced SMAD1 phosphorylation by targeting SMAD7. Additionally, administration of miR-526b-3p mimics or miR-590-5p mimics successfully promoted the chondrogenic differentiation of human BMSCs. Collectively, our study suggests that modification of BMSCs using melatonin or miRNA transduction could be an effective therapy for cartilage damage and degeneration.

Melatonin rescued interleukin 1β-impaired chondrogenesis of human mesenchymal stem cells

BACKGROUND

Osteoarthritis (OA) is a widespread arthritic disease and a primary cause of disability. Increasing evidence suggests that inflammation has a pivotal part in its pathogenesis. Interleukin-1β (IL-1β) is a primary mediator of local inflammatory processes in OA. Current therapies for OA mainly focus on the symptoms of the advanced stage of the disease. The possible utilization of bone marrow mesenchymal stem cells (BMSCs) to regenerate cartilage is an appealing method, but in the case of OA requires chondrogenesis to take place within an inflamed environment. Our previous study showed that melatonin (MLT) can promote chondrogenic differentiation of MSCs, but whether MLT can rescue IL-1β-impaired chondrogenesis in human BMSCs has not yet been established. MLT, which can have anti-inflammatory and prochondrogenic effects, has demonstrated potential in defeating IL-1β-induced inhibition of chondrogenesis and further study should be conducted.

METHODS

Human bone marrow-derived MSCs were separated and cultured based on our system that was already documented. A high-density micromass culture system was used for the chondrogenic differentiation of human BMSCs, which was also described previously. Human BMSCs were induced for chondrogenesis for 7, 14, and 21 days with the treatment of IL-1β and MLT. The cultured cartilage pellets were then evaluated by morphology, extracellular matrix accumulation, and chondrogenic, metabolic, and apoptotic marker expression. Furthermore, cell apoptosis was assessed by TUNEL assay. The phosphorylation level P65 and IκBα of the NF-κB pathway activity was explored on day 21 of chondrogenic differentiation of BMSCs.

RESULTS

The current evaluation showed that MLT can save IL-1β-impaired chondrogenesis of human BMSCs in different aspects. Firstly, MLT can restore the chondrogenic pellet size, and rescue matrix synthesis and accumulation. Secondly, MLT can upregulate chondrogenic marker COL2A1 expression at both mRNA and protein levels, and also regulate the expression levels of other chondrogenic markers like ACAN, SOX9, and COL10A1 in the presence of IL-1β. Thirdly, MLT can maintain the metabolic balance of the chondrogenic process by suppressing expression of catabolic genes, such as MMP, MMP13, and ADAMTS4. Furthermore, MLT can subdue IL-1β-induced cell apoptosis of BMSCs throughout chondrogenesis. Meanwhile, MLT suppressed the phosphorylation level of P65 and IκBα, which were elevated by IL-1β treatment, indicating that MLT can attenuate the IL-1β-induced activation of NF-κB signaling.

CONCLUSION

The current evaluation showed that MLT can save IL-1β-impaired chondrogenesis of human BMSCs by restoring the pellet size and matrix accumulation, and maintaining the metabolic balance, reducing cell apoptosis. Our study also showed that MLT can attenuate the IL-1β-induced activation of the NF-κB signaling pathway, which is the most important pathway downstream of IL-1β, and plays a crucial role in inflammation, apoptosis, and metabolism. Thus, MLT has prospects for treating OA due to its multifaceted functions, such as mitigating inflammation, maintaining metabolic balance, and mitigating apoptosis.

Collagen type II is downregulated in the degenerative nucleus pulposus and contributes to the degeneration and apoptosis of human nucleus pulposus cells

Degenerative disc disease (DDD) is a common degenerative condition initiated mainly within the nucleus pulposus (NP). To date, the etiopathogenesis of DDD remains unclear, and because no effective therapeutic strategies are available to target its pathological processes, DDD is still treated with symptomatic interventions that are far from adequate. Collagen type II is one of the major matrix components of the NP, and is considered to be essential to NP homeostasis. However, the specific mechanisms by which collagen type II influences NP cells remain unknown. In the present study, collagen type II expression was detected using immunohistochemistry analysis and quantitative polymerase chain reaction, and it was demonstrated to be significantly downregulated in NP tissues from patients with DDD compared with nondegenerative controls. To further explore the mechanism in vitro, interleukin (IL)-1β stimulation was used to induce degeneration of a human NP cell line. IL-1β stimulation upregulated both the mRNA and protein levels of the catabolic markers matrix metalloproteinase 13 (MMP13) and a disintegrin and metalloproteinase with thrombospondin motifs 4 (ADAMTS4), while it downregulated the anabolic makers aggrecan and collagen type II. However, addition of purified collagen type II prevented this IL-1β-induced metabolic disturbance of the NP cells. Furthermore, IL-1β stimulation significantly promoted apoptosis in NP cells, while collagen type II treatment decreased the apoptotic rate and the protein levels of cleaved caspase-3. In conclusion, collagen type II exhibited protective effects in suppressing NP cell degeneration through its anticatabolic, proanabolic and antiapoptotic effects, suggesting that it may be a promising therapeutic agent for the prevention and treatment of DDD.

Abstract P5-02-03: Evaluating the feasibility of a web-based preference-tolerant randomized trial of risk-based vs. annual breast cancer screening: WISDOM study pilot

Background: The WISDOM Study (Women Informed to Screen Depending on Measures of risk) aims to examine the effectiveness of personalized breast cancer screening and to bring objective recommendations to the current mammography screening debate. The WISDOM Study is a 100,000 woman randomized trial with a preference-tolerant design that will determine if risk-based screening (RBS) vs. annual screening, is as safe, less morbid, enables prevention and is preferred by women. A pilot was conducted to test the logistics of online participation and examine the acceptance of the study design and approach.

Methods: Women were recruited from the UCSF site of the Athena Breast Health Network, a clinical care-research cohort of 110,000 women from the 5 University of California Medical Centers and Sanford Health. The pilot recruited women via email who were 40 -74 years of age with no history of breast cancer and a normal mammogram in the past year. Those interested visited the WISDOM Study website (wisdomstudy.org), signed up, elected randomization or self-selection, provided electronic consent using DocuSign (eConsent), and completed genetic testing (RBS arm). The Breast Cancer Surveillance Consortium (BCSC) model (standard risk factors, ethnicity, and breast density) in addition to genetic testing (9 genes and 75 SNPs) was used to calculate breast cancer risks that informed the start and frequency of screening for women in the RBS arm. BCSC was also used in the annual screening arm but did not inform mammography screening recommendations. The pilot used a mixed method approach (using enrollment data, Exit Survey data, individual interviews and focus groups) to assess enrollment preferences, randomization acceptance and overall study workflow.

Results: The online electronic enrollment process and patient engagement portal was successfully implemented. In total, 639 women were invited, 235 registered (34%), and 171 (27%) consented to the pilot. Of these, 74% (127) elected to be randomized, and 26% chose to self-assign (66% chose annual screening (29)). Mean age was 56 years and the ethnic breakdown of the cohort was: 79% White, 10% Asian, 7% Latino, 3% Black, 1% other. 92% of those in the risk-based arm of the study completed genetic testing and were given results; only one genetic mutation was identified and occurred in CHEK2. Within the RBS arm (78), mammography recommendations were: 61% no further mammography until the age of 50, 22% biennial, 11% annual, and 6% every 6 month alternating MRI and mammogram. Exit Survey data illuminated confusion in study arm names (risk-based vs. annual), randomization acceptance (74%), annual arm preference in the self-selection group (66%), eConsent satisfaction (90%), enrollment process ease of use (88%), and website content, navigation and appearance satisfaction (66%). The pilot concluded in May 2016 to allow for refinements prior to the full trial.

Conclusion: Our pilot demonstrates that the majority of women are willing to be randomized and participate in an online screening study to answer the important question on optimal breast cancer screening. The pilot study results will inform implementation of the 100,000 women WISDOM Study which launches in fall of 2016.

Citation Format: Stover Fiscalini A, Theiner S, Kaplan C, Sarrafan S, Sawyer S, Liang A, Rosenberg-Wohl S, Gordon D, Frick M, Borowsky A, Anton-Culver H, Naeim A, LaCroix A, Cink T, Collaboration Athena Breast Health Network and Advocate Partners, Esserman L, van 't Veer L. Evaluating the feasibility of a web-based preference-tolerant randomized trial of risk-based vs. annual breast cancer screening: WISDOM study pilot [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-02-03.

Melatonin reversed tumor necrosis factor-alpha-inhibited osteogenesis of human mesenchymal stem cells by stabilizing SMAD1 protein

Tumor necrosis factor-alpha (TNFα) plays a pivotal role in inflammation-related osteoporosis through the promotion of bone resorption and suppression of bone formation. Numerous drugs have been produced to treat osteoporosis by inhibiting bone resorption, but they offer few benefits to bone formation, which is what is needed by patients with severe bone loss. Melatonin, which can exert both anti-inflammatory and pro-osteogenic effects, shows promise in overcoming TNFα-inhibited osteogenesis and deserves further research. This study demonstrated that melatonin rescued TNFα-inhibited osteogenesis of human mesenchymal stem cells and that the interactions between SMURF1 and SMAD1 mediated the crosstalk between melatonin signaling and TNFα signaling. Additionally, melatonin treatment was found to downregulate TNFα-induced SMURF1 expression and then decrease SMURF1-mediated ubiquitination and degradation of SMAD1 protein, leading to steady bone morphogenetic protein-SMAD1 signaling activity and restoration of TNFα-impaired osteogenesis. Thus, melatonin has prospects for treating osteoporosis caused by inflammatory factors due to its multifaceted functions on regulation of bone formation, bone resorption, and inflammation. Further studies will focus on unveiling the specific mechanisms by which melatonin downregulates SMURF1 expression and confirming the clinical therapeutic value of melatonin in the prevention and therapy of bone loss associated with inflammation.

Sp1 downregulates proinflammatory cytokine‑induced catabolic gene expression in nucleus pulposus cells

During the pathogenesis of intervertebral disc degeneration, pro‑inflammatory cytokines, including tumor necrosis factor‑α (TNF‑α), stimulate the degradation of the extracellular matrix (ECM) of intervertebral discs via the activity of catabolic enzymes including matrix metalloproteinases (MMPs), disintegrins and metalloproteinases with thrombospondin motifs (ADAMTSs), and cyclooxygenase 2 (Cox2). The transcriptional promoters of the human catabolic enzymes MMPs, ADAMTS, Cox2 and Syndecan 4 contain at least one specificity protein‑1 (Sp1) transcription factor‑binding site. The present study investigated the role of Sp1 in the regulation of the mRNA and protein expression of the aforementioned catabolic enzyme genes in nucleus pulposus cells, using reverse transcription‑quantitative polymerase chain reaction, western blot, transfection and RNA interference. The data demonstrated that Sp1 transcription factor protein expression is induced by TNF‑α and interleukin‑1β. Specific inhibitors of Sp1 DNA binding to its GC‑rich consensus site, WP631 and mithramycin A, partially suppressed TNF‑α‑induced catabolic enzyme expression and activity. Genetic inhibition of Sp1 by small interfering RNA‑mediated Sp1 knockdown partially inhibited catabolic enzyme induction by TNF‑α. In addition, Sp1 transcription factor inhibitors decreased the activity of MMP3, ADAMTS4 and ADAMTS5 promoters. Furthermore, chromatin immunoprecipitation revealed functional Sp1 binding sites at ‑577/‑567 bp within the ADAMTS4 promoter and ‑718/‑708 bp within the ADAMTS5 promoter. These results provide pharmacological and genetic evidence of the importance of Sp1 in catabolic enzyme gene regulation during TNF‑α stimulation. Thus, Sp1 may represent an effective target in reducing intervertebral disc‑associated ECM loss.

Autophagy attenuates the catabolic effect during inflammatory conditions in nucleus pulposus cells, as sustained by NF-κB and JNK inhibition

Proteoglycan degradation contributing to the pathogenesis of intervertebral disc (IVD) degeneration is induced by inflammatory cytokines, such as tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β). Cell autophagy exists in degenerative diseases, including osteoarthritis and inter-vertebral disc degeneration. However, the autophagy induced by TNF-α and IL-1β and the corresponding molecular mechanism appear to be cell-type dependent. The effect and mechanism of autophagy regulated by TNF-α and IL-1β in IVDs remains unclear. Additionally, the impact of autophagy on the catabolic effect in inflammatory conditions also remains elusive. In the present study, autophagy activator and inhibitor were used to demonstrate the impact of autophagy on the catabolic effect induced by TNF-α. A critical role of autophagy was identified in rat nucleus pulposus (NP) cells: Inhibition of autophagy suppresses, while activation of autophagy enhances, the catabolic effect of cytokines. Subsequently, the autophagy-related gene expression in rat NP cells following TNF-α and IL-1β treatment was observed using immunofluorescence, quantitative polymerase chain reaction and western blot analysis; however, no association was present. In addition, nuclear factor κB (NF-κB), c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinases and p38 mitogen-activated protein kinase inhibitors and TNF-α were used to determine the molecular mechanism of autophagy during the inflammatory conditions, and only the NF-κB and JNK inhibitor were found to enhance the autophagy of rat NP cells. Finally, IKKβ knockdown was used to further confirm the effect of the NF-κB signal on human NP cells autophagy, and the data showed that IKKβ knockdown upregulated the autophagy of NP cells during inflammatory conditions.

MicroRNA-21 promotes osteogenic differentiation by targeting small mothers against decapentaplegic 7

Previous studies have suggested that microRNAs (miRNAs/miRs) may positively or negatively control osteogenic differentiation and mineralization by targeting negative regulators of osteogenesis or important osteogenic factors. miR-21 is important in osteoblast differentiation and Smad7 is a critical regulator of osteogenic differentiation, which inhibits proliferation, differentiation and mineralization in mouse osteoblast cells. However, the association between Smad7 and miR-21 remain to be elucidated. In the present study, miR-21 was found to promote the level of osteogenic differentiation and increase matrix mineralization in MC3T3-E1 cells. Furthermore, Smad7 was identified as a direct target of miR-21 in the MC3T3-E1 cells. The overexpression of miR-21 affected the protein levels of SMAD7, but not the mRNA levels, which suggested that miR-21 regulates the levels of SMAD7 by inhibiting translation, rather than by promoting mRNA decay. Forced expression of miR-21 promoted osteogenic differentiation and mineralization, while inhibition of miR-21 suppressed these processes. The present study also identified for the first time, to the best of our knowledge, the promotion of osteogenic differentiation and mineralization by miR-21, by repressing the expression of Smad7.

Endoplasmic reticulum stress-unfolding protein response-apoptosis cascade causes chondrodysplasia in a col2a1 p.Gly1170Ser mutated mouse model

The collagen type II alpha 1 (COL2A1) mutation causes severe skeletal malformations, but the pathogenic mechanisms of how this occurs are unclear. To understand how this may happen, a col2a1 p.Gly1170Ser mutated mouse model was constructed and in homozygotes, the chondrodysplasia phenotype was observed. Misfolded procollagen was largely synthesized and retained in dilated endoplasmic reticulum and the endoplasmic reticulum stress (ERS)-unfolded protein response (UPR)-apoptosis cascade was activated. Apoptosis occurred prior to hypertrophy, prevented the formation of a hypertrophic zone, disrupted normal chondrogenic signaling pathways, and eventually caused chondrodysplasia. Heterozygotes had normal phenotypes and endoplasmic reticulum stress intensity was limited with no abnormal apoptosis detected. Our results suggest that earlier chondrocyte death was related to the ERS-UPR-apoptosis cascade and that this was the chief cause of chondrodysplaia. The col2a1 p.Gly1170Ser mutated mouse model offered a novel connection between misfolded collagen and skeletal malformation. Further investigation of this mouse mutant model can help us understand mechanisms of type II collagenopathies.

Melatonin enhances chondrogenic differentiation of human mesenchymal stem cells

Intramembranous ossification and endochondral ossification are two ways through which bone formation and fracture healing occur. Accumulating amounts of evidence suggests that melatonin affects osteoblast differentiation, but little is known about the effects of melatonin on the process of chondrogenic differentiation. In this study, the effects of melatonin on human mesenchymal stem cells (MSCs) undergoing chondrogenic differentiation were investigated. Cells were induced along chondrogenic differentiation via high-density micromass culture in chondrogenic medium containing vehicle or 50 nm melatonin. Histological study and quantitative analysis of glycosaminoglycan (GAG) showed induced cartilage tissues to be larger and richer in GAG, collagen type II and collagen type X in the melatonin group than in the untreated controls. Real-time RT-PCR analysis demonstrated that melatonin treatment significantly up-regulated the expression of the genes involved in chondrogenic differentiation, including aggrecan (ACAN), collagen type II (COL2A1), collagen type X (COL10A1), SRY (sex-determining region Y)-box 9 (SOX9), runt-related transcription factor 2 (RUNX2) and the potent inducer of chondrogenic differentiation, bone morphogenetic protein 2 (BMP2). And the expression of melatonin membrane receptors (MT) MT1 and MT2 were detected in the chondrogenic-induced-MSCs by immunofluorescence staining. Luzindole, a melatonin receptor antagonist, was found to partially block the ability of melatonin to increase the size and GAG synthesis of the induced cartilage tissues, as well as to completely reverse the effect of melatonin on the gene expression of ACAN, COL2A1, COL10A1, SOX9 and BMP2 after 7 days of differentiation. These findings demonstrate that melatonin enhances chondrogenic differentiation of human MSCs at least partially through melatonin receptors.

UNC5H4-induced apoptosis in non-small cell lung cancer is not dependent on p53 status only

The aim of the present study was to investigate the expression profile and prognostic significance of uncoordinated 5 homolog 4 (UNC5H4) in patients with lung cancer and to evaluate whether UNC5H4 expression may serve as an index for radiosensitivity. UNC5H4 and p53 expression levels were detected by immunohistochemistry, apoptosis was determined by a terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay and caspase 3 activation was determined by western blotting. The results showed that UNC5H4 expression was largely located in the membrane of the normal bronchial epithelium, but absent in the membranous regions or ectopic cytoplasm of 80/130 (61.5%) non-small cell lung cancer (NSCLC) tissue samples. Abnormal UNC5H4 expression was demonstrated to correlate with the degree of differentiation (P=0.015), TNM staging (P=0.037). Cytoplasmic UNC5H4 expression was shown to correlate negatively with p53 mutant type (mt) expression (r=−0.270; P=0.002) and positively with the apoptotic index (r=0.254; P=0.004). The statistical analyses indicated that the prognosis of patients with normal UNC5H4 expression was improved compared with that of patients with abnormal UNC5H4 expression, however, no significant difference was identified (P=0.125). Exposure of NSCLC tissue samples to X-radiation increased UNC5H4 expression and caspase 3 activity significantly, irrespective of p53 mutation status. In conclusion, these results indicate that X-rays induce apoptosis via the p53 pathway, and when this pathway is compromised, an additional pathway is utilized.

Pharmaceutical nanocarrier association with chondrocytes and cartilage explants: influence of surface modification and extracellular matrix depletion

OBJECTIVE

To evaluate cartilage diffusion and isolated chondrocyte association of micelles and liposomes and to determine the effect of cell-penetrating peptide (CPP) surface functionalization and extracellular matrix depletion on chondrocyte association and cartilage diffusion, respectively.

METHODS

Rhodamine-labeled micelles and liposomes were incubated with bovine chondrocytes and cell-associated fluorescence was quantified using flow cytometry. Rhodamine-labeled CPP-modified micelles and liposomes were incubated with chondrocytes and cell-associated fluorescence was compared to unmodified nanocarriers. Rhodamine-labeled micelles and liposomes were incubated with bovine cartilage explants for 1, 2 and 4 h and cartilage-associated fluorescence was compared across groups. Cartilage explants were treated with interleukin-1 alpha (IL-1α) or with 0.25% trypsin. Rhodamine-labeled micelles and liposomes were incubated with control, IL-1 and trypsin-treated explants and cartilage-associated fluorescence was compared across groups.

RESULTS

Chondrocyte-associated fluorescence following treatment with micelles was significantly higher (P < 0.001) than fluorescence in the cells treated with liposomes while there was no difference between cell-associated fluorescence in the liposomes-treated and untreated controls. CPP-modified nanocarriers exhibited a significant increase in chondrocyte association compared to unmodified nanocarriers (P < 0.001). Micelles exhibited a time and concentration-dependent diffusion in cartilage explants while liposomes showed no diffusion. Following IL-1 and trypsin treatments, micelle diffusion in articular cartilage was significantly higher (P < 0.001) than their diffusion in untreated explants.

CONCLUSION

Micelles exhibit superior association with isolated chondrocytes compared to liposomes. Surface modification with a CPP enhances chondrocyte association of both nanocarriers. 15 nm diameter micelles are better than 138 nm diameter liposomes in penetrating articular cartilage and extracellular matrix depletion enhances micelle penetration.

Association between common variants near LBX1 and adolescent idiopathic scoliosis replicated in the Chinese Han population

Background

Adolescent idiopathic scoliosis (AIS) is one of the most common spinal deformities found in adolescent populations. Recently, a genome-wide association study (GWAS) in a Japanese population indicated that three single nucleotide polymorphisms (SNPs), rs11190870, rs625039 and rs11598564, all located near the LBX1 gene, may be associated with AIS susceptibility [1]. This study suggests a novel AIS predisposition candidate gene and supports the hypothesis that somatosensory functional disorders could contribute to the pathogenesis of AIS. These findings warrant replication in other populations.

Methodology/Principal Findings

First, we conducted a case-control study consisting of 953 Chinese Han individuals from southern China (513 patients and 440 healthy controls), and the three SNPs were all found to be associated with AIS predisposition. The ORs were observed as 1.49 (95% CI 1.23–1.80, P = 5.09E-5), 1.70 (95% CI 1.42–2.04, P = 1.17E-8) and 1.52 (95% CI 1.27–1.83, P = 5.54E-6) for rs625039, rs11190870 and rs11598564, respectively. Second, a case-only study including a subgroup of AIS patients (N = 234) was performed to determine the effects of these variants on the severity of the condition. However, we did not find any association between these variants and the severity of curvature.

Conclusion

This study shows that the genetic variants near the LBX1 gene are associated with AIS susceptibility in Chinese Han population. It successfully replicates the results of the GWAS, which was performed in a Japanese population.

Sustained release of melatonin from poly (lactic-co-glycolic acid) (PLGA) microspheres to induce osteogenesis of human mesenchymal stem cells in vitro

Melatonin promotes bone formation and prevents bone degradation via receptor-dependent or receptor-independent actions. The aim of this study is to encapsulate melatonin into poly (lactic-co-glycolic acid) (PLGA) microspheres (PLGA-MEL-MS) and create a melatonin sustained release system, then to evaluate its effect on the osteogenesis of human mesenchymal stem cells (hMSCs) in vitro. PLGA-MEL-MS were prepared by single emulsion solvent evaporation technique. Scanning electron microscopy demonstrated the incorporation of melatonin did not disturb the conventional generation of PLGA microspheres in size and morphology. In vitro drug release assay showed that PLGA-MEL-MS exhibited a biphasic drug release pattern: a low initial burst release effect with approximately 40% drug release at the first 3 days and a relatively retarded and continuous release with about 85% drug release over the 25 days. Cell proliferation assay demonstrated that PLGA-MEL-MS had no apparent effect on proliferation of human MSCs. In an osteogenesis assay, PLGA-MEL-MS obviously enhanced alkaline phosphatase (ALP) mRNA expression and increased ALP activity compared to that in the control group. Meanwhile, several markers of osteoblast differentiation were also significantly upregulated, including runx2, osteopontin, and osteocalcin. Furthermore, quantificational alizarin red-based assay demonstrated that PLGA-MEL-MS significantly enhanced calcium deposit of hMSCs compared to the controls. Therefore, this simple melatonin sustained release system can control released melatonin to generate a microenvironment with a relatively stable concentration of melatonin for a period of time to support osteogenic differentiation of hMSCs in vitro. This suggests that this system may be used as bone growth stimulator in bone healing in vivo.

Increased macroautophagy in the pathological process of intervertebral disc degeneration in rats

OBJECTIVE

Macroautophagy increases with age in rat intervertebral discs; however, the effect of macroautophagy on the process of intervertebral disc degeneration (IVDD) is still unclear. The aim of this study was to examine the presence of autophagosome, as well as the levels of Beclin-1 and LC3 proteins, in vivo. Additionally, in vitro evidence of macroautophagy and GRP78 and GADD153 protein levels were investigated to explore the mechanism of macroautophagy in the process of IVDD.

METHODS

Male Sprague-Dawley rats, aged 2 months, were randomly divided into six groups (three control and three model groups, n = 8 per group). At the 6-, 12-, and 18-week time points, autophagosomes in nucleus pulposus cells were detected with transmission electron microscope (TEM). Expression of Beclin-1 and LC3 protein levels within intervertebral disc was detected using Western blotting analysis. Then, the rat annulus fibrosus cells were isolated and cultured with Earle's balanced salt solution. At 1, 2, and 3 hr of culture, autophagosomes were detected using monodansylcadaverine assay, and LC3, Beclin-1, GRP78, and GADD153 protein levels were detected using Western blotting analysis.

RESULTS

Transmission electron microscopy revealed autophagosomes within nucleus pulposus cells in both the control and model groups. At 6-, 12-, and 18-week posttreatments, the levels of Beclin-1 and the LC3-II/LC3-I protein ratio in the model groups were higher than those in the control groups (p < 0.05). Compared with the control rats, amino acid starvation increased the number of monodansylcadaverine-positive cells and the LC3-II/LC3-I protein ratio in the model rats. Moreover, the in vitro levels of Beclin-1, GRP78, and GADD153 proteins were increased with the prolongation of amino acid starvation (p < 0.05).

CONCLUSIONS

Macroautophagy was present and was associated with increased pathological process of IVDD in rats. Macroautophagy of intervertebral disc cells is possibly secondary to endoplasmic reticulum stress.