Identification and validation of hub genes and pathways associated with mitochondrial dysfunction in hypertrophy of ligamentum flavum.

Background: Lumbar spinal stenosis which can lead to irreversible neurologic damage and functional disability, is characterized by hypertrophy of ligamentum flavum (HLF). Recent studies have indicated that mitochondrial dysfunction may contribute to the development of HLF. However, the underlying mechanism is still unclear. Methods: The dataset GSE113212 was obtained from the Gene Expression Omnibus database, and the differentially expressed genes were identified. The intersection of DEGs and mitochondrial dysfunction-related genes were identified as mitochondrial dysfunction-related DEGs. Gene Ontology analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, and Gene Set Enrichment Analysis were performed. Protein-protein interaction network was constructed, and miRNAs and transcriptional factors of the hub genes were predicted via the miRNet database. Small molecule drugs targeted to these hub genes were predicted via PubChem. Immune infiltration analysis was performed to evaluate the infiltration level of immune cells and their correlation with the hub genes. In final, we measured the mitochondrial function and oxidative stress in vitro and verified the expression of hub genes by qPCR experiments. Results: In total, 43 genes were identified as MDRDEGs. These genes were mainly involved in cellular oxidation, catabolic processes, and the integrity of mitochondrial structure and function. The top hub genes were screened, including LONP1, TK2, SCO2, DBT, TFAM, MFN2. The most significant enriched pathways include cytokine-cytokine receptor interaction, focal adhesion, etc. Besides, SP1, PPARGC1A, YY1, MYC, PPARG, and STAT1 were predicted transcriptional factors of these hub genes. Additionally, increased immune infiltration was demonstrated in HLF, with a close correlation between hub genes and immune cells found. The mitochondrial dysfunction and the expression of hub genes were validated by evaluation of mitochondrial DNA, oxidative stress markers and quantitative real-time PCR. Conclusion: This study applied the integrative bioinformatics analysis and revealed the mitochondrial dysfunction-related key genes, regulatory pathways, TFs, miRNAs, and small molecules underlying the development of HLF, which improved the understanding of molecular mechanisms and the development of novel therapeutic targets for HLF.

Causality of genetically determined metabolites and metabolic pathways on osteoarthritis: a two-sample mendelian randomization study.

BACKGROUND: Osteoarthritis (OA) is one of the most prevalent musculoskeletal diseases and is the leading cause of pain and disability in the aged population. However, the underlying biological mechanism has not been fully understood. This study aims to reveal the causal effect of circulation metabolites on OA susceptibility. METHODS: A two-sample Mendelian Randomization (MR) analysis was performed to estimate the causality of GDMs on OA. A genome-wide association study (GWAS) of 486 metabolites was used as the exposure, whereas 8 different OA phenotypes, including any-site OA (All OA), knee and/or hip OA (knee/hip OA), knee OA, hip OA, spine OA, finger and/or thumb OA (hand OA), finger OA, thumb OA, were set the outcomes. Inverse-variance weighted (IVW) was used for calculating causal estimates. Methods including weight mode, weight median, MR-egger, and MR-PRESSO were used for the sensitive analysis. Furthermore, metabolic pathway analysis was performed via the web-based Metaconflict 4.0. All statistical analyses were performed in R software. RESULTS: In this MR analysis, a total of 235 causative associations between metabolites and different OA phenotypes were observed. After false discovery rate (FDR) correction and sensitive analysis, 9 robust causative associations between 7 metabolites (e.g., arginine, kynurenine, and isovalerylcarnitine) and 5 OA phenotypes were finally identified. Additionally, eleven significant metabolic pathways in 4 OA phenotypes were identified by metabolic pathway analysis. CONCLUSION: The finding of our study suggested that identified metabolites and metabolic pathways can be considered useful circulating metabolic biomarkers for OA screening and prevention in clinical practice, and can also serve as candidate molecules for future mechanism exploration and drug target selection.

Smurf1 Facilitates Oxidative Stress and Fibrosis of Ligamentum Flavum by Promoting Nrf2 Ubiquitination and Degradation.

Lumbar spinal stenosis (LSS), which can lead to irreversible neurologic damage and functional disability, is characterized by hypertrophy and fibrosis in the ligamentum flavum (LF). However, the underlying mechanism is still unclear. In the current study, the effect of Smurf1, a kind of E3 ubiquitin ligase, in promoting the fibrosis and oxidative stress of LF was investigated, and its underlying mechanism was explored. The expression of oxidative stress and fibrosis-related markers was assessed in the tissue of lumbar spinal stenosis (LSS) and lumbar disc herniation (LDH). Next, the expression of the top 10 E3 ubiquitin ligases, obtained from Gene Expression Omnibus (GEO) dataset GSE113212, was assessed in LDH and LSS, and confirmed that Smurf1 expression was markedly upregulated in the LSS group. Furthermore, Smurf1 overexpression promotes the fibrosis and oxidative stress of LF cells. Subsequently, NRF2, an important transcription factor for oxidative stress and fibrosis, was predicted to be a target of Smurf1. Mechanistically, Smurf1 directly interacts with Nrf2 and accelerates Nrf2 ubiquitination and degradation. In conclusion, the current study suggests that Smurf1 facilitated the fibrosis and oxidative stress of LF and induced the development of LSS by promoting Nrf2 ubiquitination and degradation.

Application of next-generation metagenomic sequencing in the diagnosis and treatment of acute spinal infections.

Objectives: The purpose of this study was to verify the value of metagenomic next-generation sequencing (mNGS) in detecting the pathogens causing acute spinal infection by reviewing the results of mNGS in 114 patients. Methods: A total of 114 patients were included from our hospital. Samples (tissue/blood) were sent for mNGS detection, and the remaining samples were sent to the microbiology laboratory for pathogen culture, smear, histopathological analysis, and other tests. Patients' medical records were reviewed to determine their rates of detection, time needed, guidance for antibiotic treatment and clinical outcomes. Results: mNGS showed a satisfying diagnostic positive percent agreement of 84.91% (95% confidence interval (CI): 6.34%-96.7%), compared to 30.19% (95% CI: 21.85%-39.99%) for culture and 43.40% (95% CI: 31.39%-49.97%) for conventional methods (p < 0.0125), and mNGS was found positive in 46 culture and smear negative samples. The time required for pathogen identification using mNGS ranged from 29 h to 53 h, which showed an advantage over culture (90.88 ± 8.33 h; P < 0.05). mNGS also played an important role in optimizing antibiotic regimens in patients with negative results obtained using conventional methods. The treatment success rate (TSR) of patients using mNGS-guided antibiotic regimens (20/24, 83.33%) was significantly higher than that of patients using empirical antibiotics (13/23, 56.52%) (P < 0.0001). Conclusions: mNGS shows promising potential in the pathogenic diagnosis of acute spinal infections and may enable clinicians to make more timely and effective adjustments to antibiotic regimens.

Association Between the Cervical Extensor Musculature and the Demographic Features, Symptoms, and Sagittal Balance in Patients with Multilevel Cervical Spondylotic Myelopathy.

OBJECTIVE: To obtain the quantitative measurements of the muscle morphology of cervical extensors in patients with multilevel cervical spondylotic myelopathy, and determine whether the morphological parameter of each muscle correlates with the patients' demographic features, symptoms, and cervical sagittal balance. METHODS: We retrospectively evaluated 100 hospitalized patients scheduled to undergo surgery for multilevel cervical spondylotic myelopathy. Demographic data, including age, sex, and body mass index, were recorded, and symptoms were evaluated using the visual analog scale (VAS), neck disability index (NDI), and modified Japanese Orthopedic Association scale scores. The cross-sectional area (CSA) of the multifidus, semispinalis capitis, semispinalis cervicis, splenius capitis and splenius cervicis were measured on magnetic resonance imaging. The CSA of the total extensor muscles, deep extensor muscles (DEM, consisting of multifidus and semispinalis capitis), and superficial extensor muscles (consisting of semispinalis cervicis, splenius capitis and splenius cervicis) were calculated. The adjusted CSA (aCSA) was calculated as the CSA of the muscle/CSA of the corresponding vertebral body. The fat infiltration ratio (FIR) of the posterior extensor muscles was assessed using a pseudocoloring technique. Sagittal parameters, including cervical lordosis (CL), C2-7 cervical sagittal vertical axis (SVA), T1-slope, mismatch between T1-slope and CL (T1S-CL), and range of motion, were measured. The measured parameters were compared between the males and the females, between the patients with higher muscle aCSA and the patients with lower muscle aCSA, and between the patients with and without sagittal balance. A Pearson correlation analysis was conducted to determine the correlations between the paraspinal muscle measurements, and the clinical and radiographic parameters. RESULTS: There were 67 males and 33 females in this study, and the mean age was 59.22 ± 9.54 years. Compared with females, male patients showed higher CSA and aCSA of extensor muscles. Patients with lower muscle aCSA were significantly older and had worse NDI scores, with significantly greater C2-7 SVA and T1S-CL. Patients with sagittal imbalance showed significantly lower aCSA of total extensor muscles and DEM, as well as a significantly higher FIR. Age was significantly correlated with the aCSA of each measured muscle and the FIR. The aCSA of the DEM was correlated with the NDI score, the visual analog scale score, the SVA, the T1-slope, and the T1S-CL. CONCLUSIONS: In patients with multilevel CSM, age and sex were demographic factors that were highly correlated with muscle morphology changes. Extensor muscles, especially DEM, play important roles in maintaining cervical sagittal balance and are associated with the severity of neck symptoms.

Improved biopharmaceutical performance of antipsychotic drug using lipid nanoparticles via intraperitoneal route.

This study aims to develop, characterize, and examine olanzapine-loaded solid lipid nanocarriers (OLAN-SLNs) for effective brain delivery. OLAN has poor water solubility and low penetration through blood-brain barrier (BBB). Herein, OLAN-SLNs were fabricated using high-pressure homogenization (HPH) method followed by their investigation for particle properties. Moreover, in vitro release and in vivo pharmacokinetics profiles of OLAN-SLNs were compared with pure drug. Anti-psychotic activity was performed in LPS-induced psychosis mice model. Furthermore, expressions of the COX-2 and NF-κB were measured trailed by histopathological examination. The optimized formulation demonstrated nanoparticle size (149.1 nm) with rounded morphology, negative zeta potential (-28.9 mV), lower PDI (0.334), and excellent entrapment efficiency (95%). OLAN-SLNs significantly retarded the drug release and showed sustained release pattern as compared to OLAN suspension. Significantly enhanced bioavailability (ninefold) was demonstrated in OLAN-SLNs when compared with OLAN suspension. Behavioral tests showed significantly less immobility and more struggling time in OLAN-SLNs treated mice group. Additionally, reduced expression of COX-2 and -NF κB in brain was found. Altogether, it can be concluded that SLNs have the potential to deliver active pharmaceutical ingredients to brain, most importantly to enhance their bioavailability and antipsychotic effect, as indicated for OLAN in this study.

Research on Online Rapid Sorting Method of Waste Textiles Based on Near-Infrared Spectroscopy and Generative Adversity Network.

In this paper, aiming at the application of online rapid sorting of waste textiles, a large number of effective high-content blending data are generated by using generative adversity network to deeply mine the combination relationship of blending spectra, and A BEGAN-RBF-SVM classification model is constructed by compensating the imbalance of negative samples in the data set. Various experiments show that the model can effectively extract the spectrum of pure textile samples. The classification model has high robustness and high speed, reaches the performance of similar products in the world, and has a broad application market.

A decrease in IL-33 regulates matrix degradation and apoptosis in intervertebral disc degeneration via HIF-1alpha.

Low back pain (LBP) is a common aging-associated disease that can cause disability in old people. Previous research revealed that an imbalance in the extracellular matrix (ECM) via abnormal hypoxia-inducible factor-1alpha (HIF-1α) expression in nucleus pulposus (NP) cells was one of the key factors in the pathogenesis of intervertebral disc degeneration (IDD). However, the mechanism by which the ECM is reduced in patients with IDD is not fully understood. Here, we reported that a new member of the interleukin (IL)-1 family, IL-33, was positively correlated with HIF-1α and was decreased in the NP cells of individuals with IDD. IL-33 overexpression in degenerative NP cells decreased the levels of matrix metalloproteinase-3/13 (MMP-3/13), a disintegrin and metallo-proteinase with thrombospondin motifs-4/5 (ADAMTS-4/5), and promoted ECM expression in vitro. Furthermore, we preliminarily explored the antiapoptotic effects of IL-33, which could reduce the expression of Caspase-3 and promote the level of Bcl-2 in degenerative NP cells. Furthermore, when HIF-1α expression was silenced, IL-33-mediated upregulation of ECM expression was weakened. Thus, IL-33-induced HIF-1α upregulation may represent a novel therapeutic strategy to ameliorate IDD in patients with LBP.

Oncostatin M promotes infarct repair and improves cardiac function after myocardial infarction.

Myocardial infarction (MI) is one of the leading causes of morbidity and mortality worldwide. The immune response plays a central role in post-MI cardiac repair. A growing body of evidence suggests that oncostatin M (OSM), a pleiomorphic cytokine of the interleukin (IL)-6 family, participates in the cardiac healing and remodeling process. However, previous studies have shown inconsistent results, and the exact mechanisms underlying this process have not yet been fully elucidated. We verified whether OSM is involved in the healing process and cardiac remodeling after MI and sought to explore its potential mechanisms. Our data implied OSM's role in facilitating the post-MI healing process in mice, manifested by improved cardiac functional performance and a reduction in fibrotic changes. Furthermore, our flow cytometry analysis revealed that OSM influences the dynamics of cardiac monocytes and macrophages. In mice with a blunted C-X-C motif receptor (CCR)2 signaling pathway, OSM reserved its protective roles and polarized cardiac macrophages toward a reparative phenotype. Moreover, OSM reduced the number of matrix metalloproteinase (MMP)-9+ immune cells and increased the number of tissue inhibitor of metalloproteinase (TIMP)-1+ immune cells in the infarct area, mitigating the maladaptive remodeling following MI. These findings demonstrate that OSM favorably modulates cardiac remodeling, partially by accelerating the shift in the cardiac macrophage phenotype from M1 to M2 and by correcting the MMP-9 and TIMP-1 balance.

Dexmedetomidine improves cardiac function and protects against maladaptive remodeling following myocardial infarction.

Dexmedetomidine (DEX), a highly specific and selective α2 adrenergic receptor agonist, has been demonstrated to possess potential cardioprotective effects. However, the mechanisms underlying this process remain to be fully illuminated. In the present study, a myocardial infarction (MI) animal model was generated by permanently ligating the left anterior descending coronary artery in mice. Cardiac function and collagen content were evaluated by transthoracic echocardiography and picrosirius red staining, respectively. Apoptosis was determined by the relative expression levels of Bax and Bcl­2 and the myocardial caspase­3 activity. Additionally, nicotinamide adenine dinucleotide phosphate oxidase (NOX)­derived oxidative stress was evaluated by the relative expression of Nox2 and Nox4, along with the myocardial contents of malondialdehyde (MDA) and superoxide dismutase (SOD) activity. It was demonstrated that intraperitoneal DEX treatment (20 µg/kg/day) improved the systolic function of the left ventricle, and decreased the fibrotic changes in post­myocardial infarction mice, which was paralleled by a decrease in the levels of apoptosis. Subsequent experiments indicated that the restoration of redox signaling was achieved by DEX administration, and the over­activation of NOXs, including Nox2 and Nox4, was markedly inhibited. In conclusion, this present study suggested that DEX was cardioprotective and limited the excess production of NOX­derived ROS in ischemic heart disease, implying that DEX is a promising novel drug, especially for patients who have suffered MI.

Resveratrol improves neuron protection and functional recovery through enhancement of autophagy after spinal cord injury in mice.

Resveratrol (Res), a natural phenolic compound, has been proven to have a wide variety of beneficial health effects. For example, resveratrol has neuroprotective effects in different central nervous system diseases. However, the mechanisms underlying resveratrol neuroprotection in spinal cord injury (SCI) remain unclear. In this study, we showed that resveratrol treatment improved the restoration of locomotor function, and decreased the degeneration of neurons in SCI mice, which was paralleled by a reduction of apoptosis. We further examined autophagy markers via western blot and immunofluorescence. Results showed that the beneficial effects of resveratrol were related to the promotion LC3II and beclin-1 expression. In addition, autophagy suppression with chloroquine (CQ) partially abolished apoptosis inhibition and locomotor functional improvement of Res on SCI, which indicated that the beneficial effect of resveratrol on SCI was through autophagy enhancement. In conclusion, these results illustrated that the neuroprotective effects of resveratrol in SCI are partially through autophagy stimulation, and implied that Res is a promising drug for SCI therapy.

BMSC paracrine activity attenuates interleukin-1ß-induced inflammation and apoptosis in rat AF cells via inhibiting relative NF-κB signaling and the mitochondrial pathway.

We previously showed that bone mesenchymal stem cells (BMSCs) inhibit interleukin-1 beta (IL-1ß) induced degenerative effects in NP cells by their paracrine activity, but the anti-inflammatory and anti-apoptotic effect of BMSC paracrine activity and the relative signaling pathway were not further investigated in annulus fibrosus (AF) cells. In this study, AF cells were exposed to IL-1ß, which was applied to mimic intervertebral disc degeneration (IDD) in vitro. Indirect co-culture with BMSCs in a transwell co-culture system reduced the activity of nuclear factor-κB-p65 (NF-κB-p65) through the restoration of its inhibitor IκBa. Real time polymerase chain reaction (PT-PCR) and Western blotting revealed that the up-regulation of MMP-3 and MMP-13 induced by IL-1ß were impeded by BMSC co-culture, and the decrease in aggrecan, collagen I and TIMP-1 were reversed. An ELISA showed that the increased inflammatory factors, such as nitrite, prostaglandin E-2 (PGE-2), IL-6 and cyclooxygenase-2 (COX-2), were decreased by the BMSC co-culture. Furthermore, the apoptosis rate of AF cells were detected by flow cytometry, and the apoptosis-related proteins, such as Bax, Bcl-2 and caspase-3, were analyzed by Western blotting and ELISA. The changes in mitochondrial membrane potentials were also detected by confocal microscopy. The results showed that IL-1ß induced apoptosis of AF cells was attenuated by co-culturing, which suppressed the functions of the mitochondria function. We suggest that BMSC paracrine activity has an anti-inflammation effect and anti-apoptotic effect on IDD, and it is mediated, at least in part, via the relative NF-κF and mitochondrial apoptotic pathways in AF cells.

Bone marrow-derived mesenchymal stem cells rescue injured H9c2 cells via transferring intact mitochondria through tunneling nanotubes in an in vitro simulated ischemia/reperfusion model.

The transplantation of mesenchymal stem cells (MSCs) is considered to be a promising treatment for ischemic heart disease; however, the therapeutic effects and underlying mechanisms of action require further evaluation. Mitochondrial dysfunction is a key event in simulated ischemia/reperfusion (SI/R) injury. The purpose of the present study was to investigate the mechanism of mitochondrial transfer, which may be involved the antiapoptotic action of co-culture with MSCs. An in vitro model of simulated ischemia/reperfusion (SI/R) was used in the present study. The apoptotic indexes were significantly increased when H9c2 cardiomyocytes were induced in the SI/R group. Following co-culture with bone marrow-derived (BM)-MSCs, H9c2 cells exhibited marked resistance against the SI/R-induced apoptotic process. Besides, mitochondrial transfer via a tunneling nanotube (TNT) like structure was detected by confocal fluorescent microscopy. In addition, following pretreated with latrunculin-A (LatA), an inhibitor of TNT formation, the BM-MSCs were not able to rescue injured H9c2 cells from apoptosis, as previously observed. In conclusion, the anti-apoptotic ability of BM-MSCs may be partially attributed to the recovery of mitochondrial dysfunction in SI/R, and the formation of TNTs appears to be involved in this action of mitochondrial transfer between adjacent cells.

Strontium Ranelate Reduces the Fracture Incidence in a Growing Mouse Model of Osteogenesis Imperfecta.

Osteogenesis imperfecta (OI) is a genetic bone dysplasia characterized by brittle bones with increased fracture risk. Although current treatment options to improve bone strength in OI focus on antiresorptive bisphosphonates, controlled clinical trials suggest they have an equivocal effect on reducing fracture risk. Strontium ranelate (SrR) is a promising therapy with a dual mode of action that is capable of simultaneously maintaining bone formation and reducing bone resorption, and may be beneficial for the treatment of OI. In this study, SrR therapy was investigated to assess its effects on fracture frequency and bone mass and strength in an animal model of OI, the oim/oim mouse. Three-week-old oim/oim and wt/wt mice were treated with either SrR or vehicle (Veh) for 11 weeks. After treatment, the average number of fractures sustained by SrR-treated oim/oim mice was significantly reduced compared to Veh-treated oim/oim mice. Micro-computed tomographic (µCT) analyses of femurs showed that both trabecular and cortical bone mass were significantly improved with SrR treatment in both genotypes. SrR significantly inhibited bone resorption, whereas bone formation indices were maintained. Biomechanical testing revealed improved bone structural properties in both oim/oim and wild-type (wt/wt) mice under the treatment, whereas no significant effects on bone brittleness and material quality were observed. In conclusion, SrR was able to effectively reduce fractures in oim/oim mice by improving bone mass and strength and thus represents a potential therapy for the treatment of pediatric OI. © 2015 American Society for Bone and Mineral Research.

An in vitro investigation into the role of bone marrow­derived mesenchymal stem cells in the control of disc degeneration.

Excessive apoptosis and high expression levels of interleukin­1ß (IL­1ß) in disc cells have been reported to serve important roles in intervertebral disc degeneration (IVDD). Previous studies investigating mesenchymal stem cells (MSCs) have indicated potential for their use in the treatment of IVDD. However, the therapeutic potential and anti­apoptotic ability of MSCs remains to be fully elucidated. The present study aimed to establish an in vitro model for bone marrow­derived MSC (BMSC) therapy by investigating the anti­apoptotic effects, in addition to the migration of BMSCs to nucleus pulposus (NP) cells stimulated by IL­1ß. A co-culture system of BMSCs and NP cells was founded. Following inflammatory stimulation, the NP cells exhibited increased indexes for inflammation­induced degeneration. The degenerative and apoptotic indexes were significantly reduced when NP cells were co­cultured with BMSCs. Compared with the indirect co-culture group, the direct co-culture group exhibited an improved capacity for anti-apoptosis. In addition, IL­1ß­stimulated NP cells attracted and mediated the migration of BMSCs. Mitochondrial transfer from BMSCs to NP cells by tunneling nanotubes was also observed. In conclusion, the anti­apoptosis and the migration, in addition to mitochondrial transfer associated with BMSC treatments in IVDD, were investigated in vitro in the present study. The interaction between stimulated NP cells and BMSCs is likely involved in to simulating the in vivo process of stem cell­mediated repair.

[A historic cohort study on the survival rate and the correlated risk factors regarding 174 patients with subarachnoid hemorrhage].

OBJECTIVE: To describe the survival state and to investigate the risk factors of death on patients with subarachnoid hemorrhage (SAH). METHODS: Age, past history, number of encephalic region suffering SAH, laboratory examination indexes, therapeutic measures, complications and prognosis of 174 patients with SAH were followed-up and investigated. The survival states and risk factors of death of the patients with SAH were identified by both Kaplan-Meier survival analysis and Cox proportional risk model. RESULTS: There were 10 patients (5.75%) losing follow-up investigation and 164 patients with SAH completed the follow-up investigation. 66 patients died and the longest follow-up investigation time was 5.64 years. The survival rates of 28 days, 1 year and 3-5 years were 70.60%, 63.40% and 57.20% respectively. The treatment of nimotop, aneurysm occlusion treatment and aneurysm embolotherapy could decrease the death of SAH. At the same time, advanced age, the long time smoking, hyponatremia, the rising of leucocyte in acute stage, repeated hemorrhage and cerebral angio spasm were the independent risk factors to the death of patients. CONCLUSION: Prognosis of patients with advanced age, the rising of leucocyte in acute stage, gastrointestinal blooding, hyponatremia, repeated hemorrhage and cerebral angio spasm were unfavorable. When giving patients with aneurysm, the aneurysm occlusion and embolotherapy and nimotop treatment, the death risk could be reduced.