Capsule closure has better hip function than non-closure in hip arthroscopy for femoracetabular impingement: A systematic review and meta-analysis.

Background: The impact of capsular closure vs non-closure in hip arthroscopy for femoracetabular impingement (FAI) was assessed by a meta-analysis. Methods: With the most recent search update occurring in August 2022, relevant studies were found by searching the Pubmed and EMBASE databases. A collection of studies was made that conducted hip arthroscopy for FAI. Review Manager 5.3 was used to carry out the meta-analysis. The dichotomous and continuous factors were compared using the odds ratios (OR) and mean differences (MD). A fixed-effect or random-effect model was chosen, depending on the degree of heterogeneity (I2). Forest plots were used to assess the results. A significance level of P < 0.05 was applied to the statistical analysis. Results: Ultimately, 15 studies were incorporated into the meta-analysis. The surgery time was longer for the capsular closure group (CC group) compared to the non-closure (NC group) group. (P < 0.001, SMD = 8.59, 95%CI [7.40, 9.77], I2 = 32 %). Following hip arthroscopy, the CC group's mHHS was superior to that of the NC group (P = 0.001, MD = 2.05, 95%CI [0.83, 3.27], I2 = 42 %), HOS-ADL (P < 0.001, MD = 4.29, 95%CI [3.08, 5.50], I2 = 0 %). The capsular closure group had a reduced rate of postoperative complications (P = 0.001, OR = 0.21, 95%CI [0.08, 0.54], I2 = 0 %) and conversion to THA (P = 0.01, OR = 0.42, 95%CI [0.21, 0.83], I2 = 0 %) following hip arthroscopy than the non-closure group. The revision rate, VAS, and postoperative HOS-SSS did not significantly differ between these two groups (P＞0.05). Conclusion: The current meta-analysis found that the closed group had a lower complication rate and considerably greater mHHS and HOS-ADL following surgery compared to the non-closed capsule group. Whether this is related to the continuous progress of biomechanical and clinical research techniques deserves our attention. Level of evidence: Level IV, systematic review of Level I through Level III studies.

Chronic ACLD Knees with Early Developmental Cartilage Lesions Exhibited Increased Posterior Tibial Translation during Level Walking.

OBJECTIVE: Early articular cartilage lesion (CL) is a vital sign in the onset of posttraumatic knee osteoarthritis (PTOA) in patients with anterior cruciate ligament deficiency (ACLD). Researchers have suggested that altered kinematics could accelerate CLs and, therefore, lead to the onset of PTOA. However, little is known about whether specific knee kinematics exist that lead to early CL in chronic ACLD knees. Level walking is the most frequent and relevant in vivo activity, which greatly impacts knee health. We hypothesized that the knee kinematics during level walking in chronic ACLD knees with early tibiofemoral CL would significantly differ from those of chronic ACLD knees without early tibiofemoral CL. METHODS: Thirty patients with a chronic ACLD history, including 18 subjects with CLs and 12 subjects without CLs, and 35 healthy control subjects were recruited for the study from July 2020 to August 2022. The knee kinematic data during level walking were collected using a three-dimensional motion analysis system. The kinematic differences between groups were compared using statistical parametric mapping with one dimension for One-Way ANOVA. The cartilage statuses of the ACLD knees were assessed via MRI examination. The CLs distribution of subjects was evaluated using a modified Noyes scale and analyzed by chi-square tests. RESULTS: ACLD knees with CLs had significantly greater posterior tibial translation (7.7-8.0mm, 12%-18% gait cycle GC, p = 0.014) compared to ACLD knees without CLs during level walking. ACLD knees with CLs had greater posterior tibial translation (4.6-5.5mm, 0%-23% GC, p < 0.001; 5.8-8.0mm, 86%-100% GC, p < 0.001) than healthy controls during level walking. In the group of ACLD knees with CLs, CL is mainly located in the back of the tibia plateau and front of load bearing area of the medial femoral condyle (p < 0.05). CONCLUSION: Chronic anterior cruciate ligament deficient knees with cartilage lesions have increased posterior tibial translation compared to anterior cruciate ligament deficient knees without cartilage lesions and healthy subjects. The posterior tibial translation may play an important role in knee cartilage degeneration in ACLD knees. The increased posterior tibial translation and cartilage lesion characteristics may improve our understanding of the role of knee kinematics in cartilage degeneration and could be a helpful potential reference for anterior cruciate ligament deficient therapy, such as physical training to improve abnormal kinematic behavior.

Transplantation of Wnt5a-modified Bone Marrow Mesenchymal Stem Cells Promotes Recovery After Spinal Cord Injury via the PI3K/AKT Pathway.

Spinal cord injury (SCI) is a severe neurological condition that can lead to paralysis or even death. This study explored the potential benefits of bone marrow mesenchymal stem cell (BMSC) transplantation for repairing SCI. BMSCs also differentiate into astrocytes within damaged spinal cord tissues hindering the cell transplantation efficacy, therefore it is crucial to enhance their neuronal differentiation rate to facilitate spinal cord repair. Wnt5a, an upstream protein in the non-classical Wnt signaling pathway, has been implicated in stem cell migration, differentiation, and neurite formation but its role in the neuronal differentiation of BMSCs remains unclear. Thus, this study investigated the role and underlying mechanisms of Wnt5a in promoting neuronal differentiation of BMSCs both in vivo and in vitro. Wnt5a enhanced neuronal differentiation of BMSCs in vitro while reducing astrocyte differentiation. Additionally, high-throughput RNA sequencing revealed a correlation between Wnt5a and phosphoinositide 3-kinase (PI3K)/protein kinase B(AKT) signaling, which was confirmed by the use of the PI3K inhibitor LY294002 to reverse the effects of Wnt5a on BMSC neuronal differentiation. Furthermore, transplantation of Wnt5a-modified BMSCs into SCI rats effectively improved the histomorphology (Hematoxylin and eosin [H&E], Nissl and Luxol Fast Blue [LFB] staining), motor function scores (Footprint test and Basso-Beattie-Bresnahan [BBB]scores)and promoted neuron production, axonal formation, and remodeling of myelin sheaths (microtubule associated protein-2 [MAP-2], growth-associated protein 43 [GAP43], myelin basic protein [MBP]), while reducing astrocyte production (glial fibrillary acidic protein [GFAP]). Therefore, targeting the Wnt5a/PI3K/AKT pathway could enhance BMSC transplantation for SCI treatment.

Dual Cannula Combined With Modified Shoelace Continuous Capsular Closure Technique in Hip Arthroscopic Surgery.

The Technical Note aims to present an arthroscopic capsular closure technique at the end of the hip arthroscopy. The technology employs a dual-channel approach and modified shoelace suture technique to continuously suture the hip capsule. Recent studies have indicated that routine intraoperative repair of the articular capsule at the end of the hip arthroscopy is advocated. However, the majority of the hip capsular closure techniques are relatively complex, time-consuming, and bring many complications, which has hindered their widespread use in clinical practice. Herein, we provide an arthroscopic capsular closure technique using the modified shoelace continuous suture in combination with a dual cannula for correcting hip instability during hip arthroscopic surgery of femoroacetabular impingement.

Transplantation of MiR-28-5p-Modified BMSCs Promotes Functional Recovery After Spinal Cord Injury.

Traumatic spinal cord injury (TSCI) is a prevalent central nervous system condition that imposes a significant burden on both families and society, affecting more than 2 million people worldwide. Recently, there has been increasing interest in bone marrow mesenchymal stem cell (BMSC) transplantation as a promising treatment for spinal cord injury (SCI) due to their accessibility and low immunogenicity. However, the mere transplantation of BMSCs has limited capacity to directly participate in the repair of host spinal cord nerve function. MiR-28-5p, identified as a key differentially expressed miRNA in spinal cord ischemia-reperfusion injury, exhibits differential expression and regulation in various neurological diseases. Nevertheless, its involvement in this process and its specific regulatory mechanisms in SCI remain unclear. Therefore, this study aimed to investigate the potential mechanisms through which miR-28-5p promotes the neuronal differentiation of BMSCs both in vivo and in vitro. Our results indicate that miR-28-5p may directly target Notch1, thereby facilitating the neuronal differentiation of BMSCs in vitro. Furthermore, the transplantation of lentivirus-mediated miR-28-5p-overexpressed BMSCs into SCI rats effectively improved footprint tests and Basso, Beattie, and Bresnahan (BBB) scores, ameliorated histological morphology (hematoxylin-eosin [HE] and Nissl staining), promoted axonal regeneration (MAP2 and growth-associated protein 43 [GAP43]), and facilitated axonal remyelination (myelin basic protein [MBP]). These findings may suggest that miR-28-5p-modified BMSCs could serve as a therapeutic target to enhance the behavioral and neurological recovery of SCI rats.

Obacunone targets macrophage migration inhibitory factor (MIF) to impede osteoclastogenesis and alleviate ovariectomy-induced bone loss.

INTRODUCTION: Osteoporosis is the most common bone disorder where the hyperactive osteoclasts represent the leading role during the pathogenesis. Targeting hyperactive osteoclasts is currently the primary therapeutic strategy. However, concerns about the long-term efficacy and side effects of current frontline treatments persist. Alternative therapeutic agents are still needed. OBJECTIVES: Obacunone (OB) is a small molecule with a broad spectrum of biological activities, particularly antioxidant and anti-inflammatory effects. This study aims to examine OB's therapeutic potential on osteoporosis and explore the rudimentary mechanisms. METHODS: Osteoclast formation and osteoclastic resorption assays were carried out to examine OB's inhibitory effects in vitro, followed by the in-vivo studies of OB's therapeutic effects on ovariectomy-induced osteoporotic preclinical model. To further study the underlying mechanisms, mRNA sequencing and analysis were used to investigate the changes of downstream pathways. The molecular targets of OB were predicted, and in-silico docking analysis was performed. Ligand-target binding was verified by surface plasmon resonance (SPR) assay and Western Blotting assay. RESULTS: The results indicated that OB suppressed the formation of osteoclast and its resorptive function in vitro. Mechanistically, OB interacts with macrophage migration inhibitory factor (MIF) which attenuates receptor activator of nuclear factor kappa B (NF-κB) ligand (RANKL)-induced signaling pathways, including reactive oxygen species (ROS), NF-κB pathway, and mitogen-activated protein kinases (MAPKs). These effects eventually caused the diminished expression level of the master transcriptional factor of osteoclastogenesis, nuclear factor of activated T cells 1 (NFATc1), and its downstream osteoclast-specific proteins. Furthermore, our data revealed that OB alleviated estrogen deficiency-induced osteoporosis by targeting MIF and thus inhibiting hyperactive osteoclasts in vivo. CONCLUSION: These results together implicated that OB may represent as a therapeutic candidate for bone disorders caused by osteoclasts, such as osteoporosis.

Polydatin administration attenuates the severe sublesional bone loss in mice with chronic spinal cord injury.

BACKGROUND: Spinal cord injury (SCI) is often accompanied by rapid and extensive bone mineral loss below the lesion level, and there is currently no gold standard for treatment. Evidence suggests that polydatin (PLD) may help promote osteogenic differentiation and exhibit anti-osteoporotic activity. However, whether PLD could reverse substantial bone loss in SCI patients, especially those with protracted injury, and the underlying regulatory mechanism have not been investigated. STUDY DESIGN: Male C57BL/6J mice were subjected to either contusion SCI or laminectomy at the T8-9 level. Eight weeks after SCI, PLD (40 mg/kg/day) or vehicle was administrated to the mice via the intragastric route for consecutive eight weeks. Blood was collected after the treatment regimen, and the tibiae and femora were removed. Bone marrow stromal cells were isolated from the long bones for ex vivo osteoblastogenesis and osteoclastogenesis assays. RESULTS: Chronic SCI led to a rapid and significant decrease in bone mineral density (BMD) of the distal femur and proximal tibia, resulting in structural deterioration of the bone tissues. Treatment with PLD largely restored BMD and bone structure. In addition, static histo-morphometric analysis revealed that PLD enhanced bone formation and inhibited bone resorption in vivo. PLD also promoted osteoblastogenesis and inhibited osteoclastogenesis ex vivo, which was accompanied by increased OPG/RANKL ratio, and reduced expression levels of CTR, TRAP, NFATc1 and c-Fos. However, PLD had no marked effect on serum 25(OH)D levels and VDR protein expression, although it did significantly lower serum and femoral malondialdehyde levels, inhibited expression level of matrix metallopeptidase 9 (MMP9), upregulated skeletal Wnt3a, Lrp5 and ctnnb1 mRNAs, and increased ß-catenin protein expression. CONCLUSIONS: PLD protected mice with chronic SCI against sublesional bone loss by modulating genes involved the differentiation and activity of osteoclasts and osteoblasts, abating oxidative stress and MMP activity, and restoring the Wnt/ß-catenin signaling pathway.

Accuracy and Safety of Robot-Assisted versus Fluoroscopy-Guided Posterior C1 Lateral Mass and C2 Pedicle Screw Internal Fixation for Atlantoaxial Dislocation: A Preliminary Study.

Objective: To compare the accuracy, efficiency, and safety of robotic assistance (RA) and conventional fluoroscopy guidance for the placement of C1 lateral mass and C2 pedicle screws in posterior atlantoaxial fusion. Methods: The data of patients who underwent posterior C1-C2 screw fixation (Goel-Harm's technique) in our hospital from August 2014 to March 2021 were retrospectively evaluated, including 14 cases under fluoroscopic guidance and 11 cases under RA. The hospital records, radiographic results, surgical data, and follow-up records were reviewed. Accuracy of screw placement was assessed using the Gertzbein and Robbins scale, and clinical outcomes were evaluated by Japanese Orthopedic Association (JOA) score, visual analogue scale (VAS), modified MacNab criteria, and postoperative complications. Results: Baseline characteristics of both groups were similar. The mean estimated blood loss in the fluoroscopic guidance and RA groups was 205.7 ± 80.3 mL and 120.9 ± 31.9 mL, respectively (p = 0.03). The mean surgical duration was 34 min longer with RA compared to that performed with free-hand (FH) method (p = 0.15). In addition, lower intraoperative radiation exposure was detected in the RA group (12.4 ± 1.4 mGy/screw) versus the FH (19.9 ± 2.1 mGy/screw) group (p = 0.01). The proportion of "clinically acceptable" screws (graded 0 and I) was higher in the RA group (93.2%) than that in the FH group (87.5%, p = 0.04). There was no significant difference in the increase of JOA score and decrease of VAS score between the two surgical procedures. Furthermore, there were no significant differences in overall clinical outcome between the two groups and no neurovascular complications associated with screw insertion. Conclusions: RA is a safe and potentially more accurate alternative to the conventional fluoroscopic-guided FH technique for posterior atlantoaxial internal fixation.

Pain Management of Hallux Valgus Surgery Is Achieved by Cocktail Therapy.

Background: Hallux valgus is a relatively common forefoot disease in clinical practice. The aim of our study was to assess the role of local cocktail drugs and postoperative pain after hallux valgus surgery. Methods: A retrospective case-control study was conducted to analyze 75 moderate to severe hallux valgus patients from June 1, 2018 to December 1, 2019. All patients were divided into cocktail and control groups according to whether the cocktail therapy was used or not after the operation. The anesthesiologist did not provide analgesic treatment other than nerve block anesthesia and intravenous anesthesia, such as analgesic pumps. The operative region of the cocktail group received a mixture of 10 ml of 0.75% ropivacaine, 10 ml of flurbiprofen axetil injection, and 1 ml of compound betamethasone injection, whereas the control group received nothing in the surgical spot. We recorded patients' VAS scores preoperatively and at 6, 24 hours postoperatively; the length of hospital stay and the number of hospitalization expenses; the scores of Kolcaba comfort level; and the scores of Pittsburgh sleep quality. Result: There was no significant difference in age or sex between the two groups. The VAS scores at 6 and 24 hours postoperatively were significantly lower in the cocktail group. The average length of hospital stay was 8.24 days in the control group and 3.73 days in the cocktail group. The average total hospitalization cost of the control group was ¥28285.16, and that of the cocktail group was ¥22366.31. In expenses of total hospitalization costs, the cocktail group was lower than the control group. Kolcaba's comfort various scores and the total score of the cocktail group were higher than the control group. The total score of PSQI and all dimensions in the experimental group were lower than those in the control group. Conclusion: We found a significant difference in the results of postoperative pain management except for age, sex, and hospitalization expenses. After hallux valgus surgery, inject cocktail drugs around the first metatarsophalangeal joint did reduce postoperative pain level. Level of Evidence. Level III, case-control study.

Would high-dose corticosteroid addition to multimodal cocktail periarticular injection contribute to prolonged pain control and better recovery following total knee arthroplasty?: study protocol for a randomized controlled trial.

BACKGROUND: Enhanced recovery following total knee arthroplasty (TKA) has been advocated to enhance postoperative recovery. Multimodal cocktail periarticular injection (MCPI) use for pain control in TKA has gained wide acceptance. MCPI-containing corticosteroids are believed to be an effective solution owing to their local anti-inflammatory effects and ability to reduce the local stress response postoperatively. However, there is conflicting evidence regarding its benefits. This trial aims to compare MCPI with a high dose of corticosteroid, normal dose of corticosteroid, and non-corticosteroid during TKA, to assess the effectiveness of MCPI containing corticosteroids in postoperative pain relief, functional improvement, rescue analgesia, and side effects and provide evidence that high-dose corticosteroids result in prolonged pain control and better recovery following TKA. METHODS: This is a double-blinded, randomized, placebo-controlled study. A total of 234 patients scheduled for TKA will be recruited. During surgery, before wound closure, 80 ml of the cocktail analgesic will be injected into the muscle and joint capsule for local infiltration analgesia; the participants will be randomly assigned to three groups to receive a high dose of betamethasone MCPI (group H), normal dose of betamethasone MCPI (group N), and non-betamethasone MCPI (group C). The following indices will be recorded and analyzed: the strongest knee pain experienced during 90° flexion at 6 h, 24 h, 48 h, 72 h, 5 days, 14 days, and 30 days after surgery; 1 min walking ability; and circumference around the patella at 2, 5, 14, and 30 days after surgery; Knee Society knee score at 14 days and 30 days after surgery; C-reactive protein and blood sedimentation; blood sugar 2, 5, 14, and 30 days following surgery; rescue analgesic consumption; and adverse events. If any participant withdraws from the trial, an intention-to-treat analysis will be performed. DISCUSSION: The results of this study will provide clinical evidence on the effectiveness of MCPI-containing corticosteroids in postoperative pain relief, functional improvement, rescue analgesia, and adverse events, as well as provide evidence on the efficacy of high-dose corticosteroids in prolonged pain control and better recovery following TKA. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR2000038671 . Registered on September 27, 2020.

Biomechanical testing of three coracoclavicular ligament reconstruction techniques with a 3D printing navigation template for clavicle-coracoid drilling.

BACKGROUND: The identification and precise clavicle-coracoid drilling during coracoclavicular (CC) ligament reconstruction for acromioclavicular (AC) joint dislocation require a high level of experience and surgical skills. Furthermore, the improvement of flexible fixation, such as Endobutton techniques for CC ligament reconstructions is ongoing. We have developed a 3D printing technique navigation template for clavicle-coracoid drilling and a novel implant for the reconstruction. This study aimed to determine the efficiency of the navigation template for clavicle-coracoid drilling and to evaluate the biomechanical performance of the novel CC ligament reconstruction technique. METHODS: A total of 24 fresh-frozen human cadaveric shoulders were randomly assigned to 1 of 3 reconstruction groups or a control group: TightRope, Triple Endobutton, and the Adjustable Closed-Loop Double Endobutton technique. Computed tomography scans, navigation template designs, and 3D printing were performed for the shoulders. Then, AC joint dislocation was simulated in the reconstruction groups, and 3 CC ligament reconstruction techniques were operated via the 3D printing template separately. Furthermore, biomechanical protocols including the translation test (load from 5 to 70 N) and the load-to-failure test were performed to characterize the behaviors and strengths. One-way ANOVA test analyzed differences in displacement under the translation load and the load at failure. RESULTS: CC ligament reconstructions were performed successfully along with the 3D printing navigation template in the 3 reconstruction groups. During the translation test, no significant difference was found in displacements among the 4 groups. Meanwhile, the mean load of all reconstruction groups at failure (Adjustable Closed-Loop Double Endobutton, 722.1620 N; TightRope, 680.4020 N; Triple Endobutton, 868.5762 N) was significantly larger than the control group (564.6264 N, P<0.05). The Triple Endobutton group had the maximum load at failure (P<0.05), however, no significant difference was noticed between the other 2 reconstruction groups (P>0.05). CONCLUSIONS: The 3D printing navigation template may become helpful and reliable for AC joint dislocation surgery. Among the 3 CC ligament reconstruction techniques, the Triple Endobutton technique has the best strength in terms of biomechanics, while the biomechanical strength of the Adjustable Closed-Loop Double Endobutton technique is reliable in comparison with the TightRope technique.

Polydatin Attenuates OGD/R-Induced Neuronal Injury and Spinal Cord Ischemia/Reperfusion Injury by Protecting Mitochondrial Function via Nrf2/ARE Signaling Pathway.

Spinal cord ischemia/reperfusion injury (SCII) is a devastating complication of spinal or thoracic surgical procedures and can lead to paraplegia or quadriplegia. Neuronal cell damage involving mitochondrial dysfunction plays an important role in the pathogenesis of SCII. Despite the availability of various treatment options, there are currently no mitochondria-targeting drugs that have proven effective against SCII. Polydatin (PD), a glucoside of resveratrol, is known to preserve mitochondrial function in central nervous system (CNS) diseases. The aim of the present study was to explore the neuro- and mito-protective functions of PD and its underlying mechanisms. An in vitro model of SCII was established by exposing spinal cord motor neurons (SMNs) to oxygen-glucose-deprivation/reperfusion (OGD/R), and the cells were treated with different dosages of PD for varying durations. PD improved neuronal viability and protected against OGD/R-induced apoptosis and mitochondrial injury in a dose-dependent manner. In addition, PD restored the activity of neuronal mitochondria in terms of mitochondrial membrane potential (MMP), intracellular calcium levels, mitochondrial permeability transition pore (mPTP) opening, generation of reactive oxygen species (ROS), and adenosine triphosphate (ATP) levels. Mechanistically, PD downregulated Keap1 and upregulated Nrf2, NQO-1, and HO-1 in the OGD/R-treated SMNs. Likewise, PD treatment also reversed the neuronal and mitochondrial damage induced by SCII in a mouse model. Furthermore, the protective effects of PD were partially blocked by the Nrf2 inhibitor. Taken together, PD relieves mitochondrial dysfunction-induced neuronal cell damage by activating the Nrf2/ARE pathway and is a suitable therapeutic option for SCII.

Sodium Tanshinone IIA Silate Exerts Microcirculation Protective Effects against Spinal Cord Injury In Vitro and In Vivo.

Spinal cord microcirculation involves functioning endothelial cells at the blood spinal cord barrier (BSCB) and maintains normal functioning of spinal cord neurons, axons, and glial cells. Protection of both the function and integrity of endothelial cells as well as the prevention of BSCB disruption may be a strong strategy for the treatment of spinal cord injury (SCI) cases. Sodium Tanshinone IIA silate (STS) is used for the treatment of coronary heart disease and improves microcirculation. Whether STS exhibits protective effects for SCI microcirculation is not yet clear. The purpose of this study is to investigate the protective effects of STS on oxygen-glucose deprivation- (OGD-) induced injury of spinal cord endothelial cells (SCMECs) in vitro and to explore effects on BSCB and neurovascular protection in vivo. SCMECs were treated with various concentrations of STS (1 µM, 3 µM, and 10 µM) for 24 h with or without OGD-induction. Cell viability, tube formation, migration, and expression of Notch signaling pathway components were evaluated. Histopathological evaluation (H&E), Nissl staining, BSCB permeability, and the expression levels of von Willebrand Factor (vWF), CD31, NeuN, and Notch signaling pathway components were analyzed. STS was found to improve SCMEC functions and reduce inflammatory mediators after OGD. STS also relieved histopathological damage, increased zonula occludens-1 (ZO-1), inhibited BSCB permeability, rescued microvessels, protected motor neuromas, and improved functional recovery in a SCI model. Moreover, we uncovered that the Notch signaling pathway plays an important role during these processes. These results indicated that STS protects microcirculation in SCI, which may be used as a therapeutic strategy for SCI in the future.

Polydatin promotes the neuronal differentiation of bone marrow mesenchymal stem cells in vitro and in vivo: Involvement of Nrf2 signalling pathway.

Bone marrow mesenchymal stem cell (BMSC) transplantation represents a promising repair strategy following spinal cord injury (SCI), although the therapeutic effects are minimal due to their limited neural differentiation potential. Polydatin (PD), a key component of the Chinese herb Polygonum cuspidatum, exerts significant neuroprotective effects in various central nervous system disorders and protects BMSCs against oxidative injury. However, the effect of PD on the neuronal differentiation of BMSCs, and the underlying mechanisms remain inadequately understood. In this study, we induced neuronal differentiation of BMSCs in the presence of PD, and analysed the Nrf2 signalling and neuronal differentiation markers using routine molecular assays. We also established an in vivo model of SCI and assessed the locomotor function of the mice through hindlimb movements and electrophysiological measurements. Finally, tissue regeneration was evaluated by H&E staining, Nissl staining and transmission electron microscopy. PD (30 µmol/L) markedly facilitated BMSC differentiation into neuron-like cells by activating the Nrf2 pathway and increased the expression of neuronal markers in the transplanted BMSCs at the injured spinal cord sites. Furthermore, compared with either monotherapy, the combination of PD and BMSC transplantation promoted axonal rehabilitation, attenuated glial scar formation and promoted axonal generation across the glial scar, thereby enhancing recovery of hindlimb locomotor function. Taken together, PD augments the neuronal differentiation of BMSCs via Nrf2 activation and improves functional recovery, indicating a promising new therapeutic approach against SCI.

Time-Course Changes and Role of Autophagy in Primary Spinal Motor Neurons Subjected to Oxygen-Glucose Deprivation: Insights Into Autophagy Changes in a Cellular Model of Spinal Cord Ischemia.

Spinal cord ischemia is a severe clinical complication induced by thoracoabdominal aortic surgery, severe trauma, or compression to the spinal column. As one of the most important functional cells in the spinal cord, spinal motor neurons (SMNs) suffer most during the process since they are vulnerable to ischemic injury due to high demands of energy. Previous researches have tried various animal models or organotypic tissue experiments to mimic the process and get to know the pathogenesis and mechanism. However, little work has been performed on the cellular model of spinal cord ischemia, which has been hampered by the inability to obtain a sufficient number of pure primary SMNs for in vitro study. By optimizing the isolation and culture of SMNs, our laboratory has developed an improved culture system of primary SMNs, which allows cellular models and thus mechanism studies. In the present study, by establishing an in vitro model of spinal cord ischemia, we intended to observe the dynamic time-course changes of SMNs and investigate the role of autophagy in SMNs during the process. It was found that oxygen-glucose deprivation (OGD) resulted in destruction of neural networks and decreased cell viability of primary SMNs, and the severity increased with the prolonging of the OGD time. The OGD treatment enhanced autophagy, which reached a peak at 5 h. Further investigation demonstrated that inhibition of autophagy exacerbated the injury, evidencing that autophagy plays a protective role during the process.

Mechanics and Biology Interact in Intervertebral Disc Degeneration: A Novel Composite Mouse Model.

The aim of this study was to distinguish the characteristics of intervertebral disc degeneration (IVDD) originating from mechanics imbalance, biology disruption, and their communion, and to develop a composite IVDD model by ovariectomy combined with lumbar facetectomy for mimicking elderly IVDD with osteoporosis and lumbar spinal instability. Mice were randomly divided into four groups and subjected to sham surgery (CON), ovariectomy (OVX), facetectomy (mechanical instability, INS) or their combination (COM), respectively. Radiographical (n = 4) and histological changes (n = 8) of L4/5 spinal segments were analyzed. Tartrate-resistant acid phosphatase (TRAP) staining was conducted to detect osteoclasts, and expression of osterix (OSX), type I collagen (Col I), type II collagen (Col II) and vascular endothelial growth factor (VEGF) were evaluated by immunochemistry. OVX affected the body's metabolism but INS did not, as the body weight increased and uterus weight decreased in OVX and COM mice compared to CON and INS mice. OVX, INS, and COM caused IVDD in various degrees at 12 weeks after surgery. However, the major pathogeneses of OVX- and INS-induced IVDD were different, which focused on endplate (EP) remodeling and annulus fibrosus (AF) collapse, respectively. OVX induced osteopenia of vertebra. In contrast, INS promoted the stress-adaptive increase of subchondral bone trabeculae. The COM produced a reproducible severe IVDD model with characteristics of sparse vertebral trabeculae, cartilaginous EP ossification, subchondral bone sclerosis, fibrous matrix disorder, angiogenesis, disc stiffness, as well as space fusion. Additionally, all groups had elevated bone and cartilage turnover compared with CON group, as the quantity of trap + osteoclasts and the osteogenic OSX expression increased in these groups. Likewise, the VEGF expression levels were similar, accompanied by the altered matrix expression of disc, including the changed distribution and contents of Col II and Col I. The findings suggested that the composite mouse model to some extent could effectively mimic the interactions of biology and mechanics engaged in the onset and natural course of IVDD, which would be more compatible with the IVDD of elderly with vertebral osteoporosis and spinal instability and benefit to further clarify the complicated mechanobiological environment of elderly IVDD progression.

Fasudil enhanced differentiation of BMSCs in vivo and vitro, involvement of P38 signaling pathway.

Bone mesenchymal stem cells (BMSCs) are a well-known donor graft source due to their potential for self-renewal and differentiation into multi-lineage cell types, including osteoblasts that are critical for fracture healing. Fasudil (FAS), a Rho kinase inhibitor, has been proven to induce the differentiation of bone marrow stem cells (BMSCs) into neuron-like cells. However, its role in the osteogenesis of BMSCs remain uncertain. Herein, we for the first time studied the effects of FAS on osteogenic differentiation in a mouse fracture model and further explored the involved mechanisms in mouse BMSCs. The results showed that FAS stimulated bone formation in the fracture mouse model. Additionally, at 30 µM, FAS significantly promotes alkaline phosphatase activity, mineralization, and the expression of osteogenic markers COL-1, RUNX2 and OCN in murine BMSCs. Blocking of P38 by SB202190 significantly reversed the effects of FAS, in vitro, suggesting that P38, but not ERK or JNK activation is required for FAS-induced osteogenesis. Collectively, our results indicate that FAS may be a promising agent for promoting fracture healing.

Tangeretin Inhibits Oxidative Stress and Inflammation via Upregulating Nrf-2 Signaling Pathway in Collagen-Induced Arthritic Rats.

BACKGROUND/AIMS: Tangeretin (TAN), a major phytochemical in tangerine peels and an important Chinese herb, has multiple biological properties, especially antioxidative and anti-inflammatory effects. However, the mechanisms remain unclear. Based on these findings, the aim of the present study was to assess the antioxidant and anti-inflammatory properties of TAN in bovine type II collagen-induced arthritis rats. METHODS: TAN (50 mg/kg) was given orally once daily for 14 days. The effects of treatment were evaluated by biochemical assay (articular elastase, myeloperoxidase, end products of lipid peroxidation [MDA], antioxidant enzyme, such as superoxide dismutase, catalase, glutathione), nitric oxide, and inflammatory cytokines (interleukin-1ß [IL-1ß], -IL-10, tumor necrosis factor-alpha [TNF-α], interferon-γ [IFN-γ], and prostaglandin E2 [PGE2]). The protective effects of TAN against rheumatoid arthritis (RA) were evident from the decrease in arthritis scoring. Furthermore, the Nrf-2 signaling pathway was assessed to illustrate the molecular mechanism. RESULTS: TAN had therapeutic effects on RA by decreasing the oxidative stress damage and regulating inflammatory cytokine expression, including suppression of the accumulation of MDA products, decreasing the IL-1ß, TNF-α, IFN-γ, and PGE2 levels, enhancing the IL-10 and the activity of antioxidant enzymes, which was through upregulating Nrf-2 signaling pathway. CONCLUSION: TAN might have potential as a therapeutic agent for the treatment of RA.

Huo Xue Tong Luo capsule ameliorates osteonecrosis of femoral head through inhibiting lncRNA-Miat.

ETHNOPHARMACOLOGICAL RELEVANCE: Traditional Chinese medicine has a long history of treating various bone diseases including osteoporosis and osteonecrosis etc. In clinical treatment, Huo Xue Tong Luo capsule (HXTL capsule) containing Peach kernel, Safflower carthamus, Angelica sinensis, Ligusticum wallichii etc, is one of the mostly used prescriptions for treating osteonecrosis of the femoral head (ONFH) with promising effects. OBJECTIVES: This study aims to identify the underlying molecular mechanism of how HXTL capsule exerts its function to ameliorate ONFH. MATERIALS AND METHODS: All femoral bone tissues were collected during surgeries. Rat bone marrow mesenchymal stem cells (rMSCs) were used. Quantitative real time PCR was used to check the relative expression levels of genes. ChIP assay was performed to evaluate the binding of H3K4me3 and H3K27me3 in Miat promoter. RESULTS: We showed that HXTL capsule promoted osteogenesis in rat MSCs as demonstrated by quantitative real time PCR and Alizarin Red S staining. Then we found silencing the endogenous lncRNA-Miat could promote osteogenesis of rMSCs. In addition, the ChIP assay showed that HXTL capsule significantly increased occupancy of H3K27me3 and decreased H3K4me3 in promoter regions of Miat, meaning HXTL capsule inhibited Miat expression through histone modifications. At last, by examining the femoral heads samples obtained from patients with ONFH during total hip arthroplasty surgery, we found the RNA level of hMiat in necrotic tissue was much higher than that of normal tissue. CONCLUSIONS: Taken together, our study shows that lncRNA-Miat might play an important role in pathogenesis of ONFH, and HXTL capsule can promote osteogenesis to ameliorate ONFH through inhibiting the transcriptional expression of Miat, at least partially.