A novel spherical GelMA-HAMA hydrogel encapsulating APET×2 polypeptide and CFIm25-targeting sgRNA for immune microenvironment modulation and nucleus pulposus regeneration in intervertebral discs.

METHODS: Single-cell transcriptomics and high-throughput transcriptomics were used to screen factors significantly correlated with intervertebral disc degeneration (IDD). Expression changes of CFIm25 were determined via RT-qPCR and Western blot. NP cells were isolated from mouse intervertebral discs and induced to degrade with TNF-α and IL-1ß. CFIm25 was knocked out using CRISPR-Cas9, and CFIm25 knockout and overexpressing nucleus pulposus (NP) cell lines were generated through lentiviral transfection. Proteoglycan expression, protein expression, inflammatory factor expression, cell viability, proliferation, migration, gene expression, and protein expression were analyzed using various assays (alcian blue staining, immunofluorescence, ELISA, CCK-8, EDU labeling, transwell migration, scratch assay, RT-qPCR, Western blot). The GelMA-HAMA hydrogel loaded with APET×2 polypeptide and sgRNA was designed, and its effects on NP regeneration were assessed through in vitro and mouse model experiments. The progression of IDD in mice was evaluated using X-ray, H&E staining, and Safranin O-Fast Green staining. Immunohistochemistry was performed to determine protein expression in NP tissue. Proteomic analysis combined with in vitro and in vivo experiments was conducted to elucidate the mechanisms of hydrogel action. RESULTS: CFIm25 was upregulated in IDD NP tissue and significantly correlated with disease progression. Inhibition of CFIm25 improved NP cell degeneration, enhanced cell proliferation, and migration. The hydrogel effectively knocked down CFIm25 expression, improved NP cell degeneration, promoted cell proliferation and migration, and mitigated IDD progression in a mouse model. The hydrogel inhibited inflammatory factor expression (IL-6, iNOS, IL-1ß, TNF-α) by targeting the p38/NF-κB signaling pathway, increased collagen COLII and proteoglycan Aggrecan expression, and suppressed NP degeneration-related factors (COX-2, MMP-3). CONCLUSION: The study highlighted the crucial role of CFIm25 in IDD and introduced a promising therapeutic strategy using a porous spherical GelMA-HAMA hydrogel loaded with APET×2 polypeptide and sgRNA. This innovative approach offers new possibilities for treating degenerated intervertebral discs.

Mulberroside A mitigates intervertebral disc degeneration by inhibiting MAPK and modulating Ppar-γ/NF-κB pathways.

BACKGROUND: Intervertebral disc degeneration (IVDD) is a common spine disease with inflammation as its main pathogenesis. Mulberroside A (MA), isolated from herbal medicine, possesses anti-inflammatory characteristics in many diseases. Whereas, there is little exploration of the therapeutic potential of MA on IVDD. This study aimed at the therapeutic potential of MA on IVDD in vivo and in vitro and the mechanism involved. METHODS: In vitro, western blotting, RT-qPCR, and immunofluorescence analysis were implemented to explore the bioactivity of MA on interleukin-1 beta (IL-1ß)-induced inflammation nucleus pulposus cells (NPCs) isolated from Sprague-Dawley male rats. In vivo, X-ray and MRI were applied to measure the morphological changes, and histological staining and immunohistochemistry were employed to investigate the histological changes of intervertebral disc sections on puncture-induced IVDD rat models. RESULTS: In vitro, MA up-regulated the expression level of anabolic-related proteins (Aggrecan and Collagen II) and decreased catabolic-related proteins (Mmp2, Mmp3, Mmp9, and Mmp13) in IL-1ß-induced NPCs. Furthermore, MA inhibits the production of pro-inflammatory factors (Inos, Cox-2, and Il-6) stimulated by IL-1ß. Mechanistically, MA inhibited the signal transduction of mitogen-activated protein kinase (MAPK) and nuclear factor kappa-B (NF-κB) pathways in IL-1ß-induced NPCs. Moreover, MA might bind to Ppar-γ and then suppress the NF-kB pathway. In vivo experiment illustrated that MA mitigates the IVDD progression in puncture-induced IVDD model. X-ray and MRI images showed MA restore the disc height and T2-weighted signal intensity after puncturing. H&E and Safranin O/Fast Green also showed MA also alleviated morphological changes caused by acupuncture. In addition, MA reversed the expression level of Mmp13, Aggrecan, Collagen II, and Ppar-γ induced in IVDD models. CONCLUSIONS: MA inhibited degenerative phenotypes in NPCs and alleviated IVDD progression via inhibiting the MAPK and NF-κB pathways; besides, MA suppressed the NF-κB pathway was attributed to activating Ppar-γ, those supported that MA or Ppar-γ might be a potential drug or target for IVDD.

Unveiling the Therapeutic Potential of hUCMSC-Derived EVs in Intervertebral Disc Degeneration through MALAT1/miR-138-5p/SLC7A11 Coexpression Regulation.

Intervertebral disc degeneration (IVDD) is a prevalent chronic condition causing spinal pain and functional impairment. This study investigates the role of extracellular vesicles (EVs) derived from human umbilical cord mesenchymal stem cells (hUCMSCs) in regulating IVDD. Using RNA-seq, we analyzed differential expressions of lncRNA and miRNA in nucleus pulposus tissues from various mouse groups. We identified key regulatory molecules, MALAT1 and miRNA-138-5p, which contribute to IVDD. Further experiments demonstrated that MALAT1 can up-regulate SLC7A11 expression by competitively binding to miR-138-5p, forming a MALAT1/miR-138-5p/SLC7A11 coexpression regulatory network. This study elucidates the molecular mechanism by which hUCMSC-derived EVs regulate IVDD and could help develop novel therapeutic strategies for treating this condition. Our findings demonstrate that hUCMSCs-EVs inhibit ferroptosis in nucleus pulposus cells, thereby improving IVDD. These results highlight the therapeutic potential of hUCMSCs-EVs in ameliorating the development of IVDD, offering significant scientific and clinical implications for new treatments.

A Novel Leverage Technique Using Monoaxial Pedicle Screw for Reduction of Thoracolumbar Compression Fractures: Surgical Technique and Analysis of Radiological Parameters.

OBJECTIVE: Thoracolumbar compression fractures resulting from high-energy injuries are a common type of spinal fracture. Satisfying reduction of compressive vertebra body is essential for the clinical outcome. However, traditional distraction technique may lead to complications including pedicle screw loosening, pedicle screw breakage, and postoperative back pain because of excessive distraction. In this study, we reported a novel technique for reduction. Additionally, the effect and postoperative radiological parameters of this technique were compared with those of traditional distraction technique. METHODS: The clinical data of 80 patients who had been treated with posterior pedicle screw fixation from January 2019 to December 2020 was retrospectively analyzed. Thirty-six patients were performed with the leverage technique, while 22 patients were treated with the traditional distraction technique. When pedicle screw fixation was performed with either the leverage technique or the traditional distraction technique, fracture reduction was completed with monoaxial pedicle screws using either the leverage maneuver or distraction of adjacent vertebrae. Clinical evaluation, including operation time, hospital stay, blood loss volume, and postoperative complications were collected. The American Spinal Injury Association (ASIA) score for neurological condition and the visual analog scale (VAS) score for pain were used to evaluate the patients' functional outcome. The radiographic analysis included local kyphotic angle (LKA), regional kyphotic angle (RKA), anterior vertebral height (AVH), posterior vertebral height (PVH), and sagittal compression (SC). The student t-test and the χ2-test (or the Fisher exact test) were used to compare the outcome measures between the two groups. RESULTS: The leverage group comprised 36 patients, while 44 patients were included in the distraction group. No statistically significant differences were found in the demographic data. The VAS score in the leverage group (3.0 ± 0.8) was significantly lower than that in the distraction group (4.2 ± 0.6) on postoperative day 1. Total correction of the LKA in the leverage group (11.5 ± 2.5°) was significantly higher than that in the distraction group (7.1 ± 1.3°) (p = 0.0004). Total correction of the RKA was higher in the leverage group (12.1 ± 4.3°) than in the distraction group (6.1 ± 0.9°) (p = 0.005). The ratio of rear pillar /front pillar correction was 0.35 ± 0.13 and 0.89 ± 0.18 in the leverage and distraction groups, respectively (p = 0.014). Total correction of the upper and lower foraminal height in the leverage group was significantly less than that in the distraction group. The leverage group had significantly higher correction of the upper and lower intervertebral space height than the distraction group. CONCLUSIONS: Our novel leverage technique provided better kyphotic reduction and restoration than compared to conventional distraction technique in the surgical treatment of thoracolumbar compression fractures.

Fractured vertebra antedisplacement reconstruction technique: a feasible treatment choice for posttraumatic thoracolumbar kyphosis.

OBJECTIVE: The goal of this study was to evaluate the feasibility of the fractured vertebra antedisplacement reconstruction technique for the treatment of posttraumatic thoracolumbar kyphosis (PTK). METHODS: A total of 22 patients with PTK who were treated with the fractured vertebra antedisplacement reconstruction technique were retrospectively analyzed. The radiological evaluation included global kyphosis, thoracolumbar angle, and sagittal vertical axis. The clinical evaluation included visual analog scale pain score, Oswestry Disability Index score, SF-12 Health Survey score, and American Spinal Injury Association grade. The complications were recorded. RESULTS: The mean global kyphosis was 55.0° ± 12.6° preoperatively, 8.5° ± 5.0° postoperatively, and 10.3° ± 4.8° at the latest follow-up (p < 0.001). The average total kyphosis correction achieved was 44.7° ± 14.2°, with a range of 23.4°-79.4°, indicating a mean final correction of 80.1%. The mean thoracolumbar angle was 46.2° ± 13.2° preoperatively, 6.6° ± 4.5° postoperatively, and 7.6° ± 4.2° at the latest follow-up (p < 0.001). The mean sagittal vertical axis was improved significantly, from 51.1 ± 24.2 mm preoperatively to 28.5 ± 17.4 mm at the latest follow-up (p = 0.001). One patient (4.5%) experienced single intervertebral fusion nonunion, and 1 patient (4.5%) experienced distal screw loosening. No patients experienced any neurological deterioration. The visual analog scale pain score, Oswestry Disability Index score, SF-12 Health Survey score, and American Spinal Injury Association grade achieved significant improvement at the latest follow-up. CONCLUSIONS: Fractured vertebra antedisplacement reconstruction technique can effectively correct kyphosis, reconstruct spinal stability, and improve the patient's symptoms and neurological function. This technique is safer, minimally traumatic, and less technically demanding to avoid osteotomy-related complications. It is a feasible treatment choice for PTK.

Clinical observation of ultraviolet therapy combined with autologous platelet-rich plasma in the treatment of chronic refractory wounds.

Refractory wounds present complex and serious clinical dilemmas in plastic and reconstructive surgeries. Currently, there are no standard guidelines for the treatment of refractory wounds. To observe the clinical effects of ultraviolet (UV) therapy combined with autologous platelet-rich plasma (PRP) on chronic refractory wounds. Between January 2021 and December 2022, 60 inpatients with chronic refractory wounds were enrolled. Twenty patients were assigned to each of control groups 1 and 2 and treatment group according to whether they received PRP or UV treatment. All the patients underwent thorough debridement. Control group 2 received UV radiation. The treatment group underwent UV radiation combined with PRP gel covering the wound. Control group 1 underwent routine dressing changes after surgery, followed by skin grafting or skin key transfer if needed. One month later, we observed the wound healing in the two groups. After 2-4 PRP gel treatments, the wounds of patients in the treatment group healed. The healing time was 25.25 ± 4.93 days, and the dressings were changed 4.15 ± 3.30 times, both of which were better outcomes than in both control groups. In the treatment group, epidermal growth factor (EGF), insulin-like growth factor (IGF), platelet-derived growth factor (PGF), and transforming growth factor ß (TGF-ß) were slightly higher, and the concentration of vascular endothelial growth factor (VEGF) was significantly higher than in the control group (p < 0.05). PRP combined with UV therapy significantly increased the concentration of wound growth factors, accelerated wound healing, shortened treatment time, reduced treatment costs, and alleviated pain in patients.

From drugs to biomaterials: a review of emerging therapeutic strategies for intervertebral disc inflammation.

Chronic low back pain (LBP) is an increasingly prevalent issue, especially among aging populations. A major underlying cause of LBP is intervertebral disc degeneration (IDD), often triggered by intervertebral disc (IVD) inflammation. Inflammation of the IVD is divided into Septic and Aseptic inflammation. Conservative therapy and surgical treatment often fail to address the root cause of IDD. Recent advances in the treatment of IVD infection and inflammation range from antibiotics and small-molecule drugs to cellular therapies, biological agents, and innovative biomaterials. This review sheds light on the complex mechanisms of IVD inflammation and physiological and biochemical processes of IDD. Furthermore, it provides an overview of recent research developments in this area, intending to identify novel therapeutic targets and guide future clinical strategies for effectively treating IVD-related conditions.

Comparative effectiveness and functional outcome of C3 & C7 dome-hybrid open-door laminoplasty with traditional unilateral open-door laminoplasty for cervical spondylotic myelopathy.

OBJECTIVE: The C3 & C7 dome-hybrid open-door laminoplasty was proven to be an effective treatment for multi-levels cervical spondylotic myelopathy (CSM). However, its superiority over traditional unilateral open-door laminoplasty (UOLP) remains questionable, and no studies have compared the efficacy of this technique with traditional UOLP. This study aimed to compare the effectiveness of C3 & C7 dome-hybrid open-door laminoplasty with traditional UOLP in treating multi-levels CSM. METHODS: A retrospective study of multi-levels CSM with laminoplasty was performed, including 35 cases of traditional UOLP and 27 cases of C3 & C7 dome-hybrid open-door laminoplasty. Radiographic evaluation parameters and clinical outcomes were recorded to evaluate the surgical effectiveness. RESULTS: There was no significant difference in demographic baseline parameters. At the final follow-up, the C2-C7 Cobb angle of the modified group was significantly greater than that of the traditional group (p = 0.026). Meanwhile, the C2-C7 SVA of the modified group was significantly smaller than that of the traditional group (p = 0.009). Clinical outcomes such as VAS, NDI, and SF-12 scores, improved significantly in the modified group compared to the traditional group, while the JOA scores had no significant difference in both groups. There was no significant difference in the overall rate of complications between the two groups. CONCLUSION: Both techniques have satisfactory outcomes in treating multi-levels CSM. Comparing with traditional UOLP, C3 & C7 dome-hybrid open-door laminoplasty has a greater superiority in reducing postoperative neck pain and maintaining the cervical sagittal alignment. It is proven to be a feasible management for patients with multi-levels CSM.

Dihydrocaffeic acid improves IL-1ß-induced inflammation and cartilage degradation via inhibiting NF-κB and MAPK signalling pathways.

Aims: Osteoarthritis (OA) is a prevalent joint disorder with inflammatory response and cartilage deterioration as its main features. Dihydrocaffeic acid (DHCA), a bioactive component extracted from natural plant (gynura bicolor), has demonstrated anti-inflammatory properties in various diseases. We aimed to explore the chondroprotective effect of DHCA on OA and its potential mechanism. Methods: In vitro, interleukin-1 beta (IL-1ß) was used to establish the mice OA chondrocytes. Cell counting kit-8 evaluated chondrocyte viability. Western blotting analyzed the expression levels of collagen II, aggrecan, SOX9, inducible nitric oxide synthase (iNOS), IL-6, matrix metalloproteinases (MMPs: MMP1, MMP3, and MMP13), and signalling molecules associated with nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) pathways. Immunofluorescence analysis assessed the expression of aggrecan, collagen II, MMP13, and p-P65. In vivo, a destabilized medial meniscus (DMM) surgery was used to induce mice OA knee joints. After injection of DHCA or a vehicle into the injured joints, histological staining gauged the severity of cartilage damage. Results: DHCA prevented iNOS and IL-6 from being upregulated by IL-1ß. Moreover, the IL-1ß-induced upregulation of MMPs could be inhibited by DHCA. Additionally, the administration of DHCA counteracted IL-1ß-induced downregulation of aggrecan, collagen II, and SOX9. DHCA protected articular cartilage by blocking the NF-κB and MAPK pathways. Furthermore, DHCA mitigated the destruction of articular cartilage in vivo. Conclusion: We present evidence that DHCA alleviates inflammation and cartilage degradation in OA chondrocytes via suppressing the NF-κB and MAPK pathways, indicating that DHCA may be a potential agent for OA treatment.

Decorin: a potential therapeutic candidate for ligamentum flavum hypertrophy by antagonizing TGF-ß1.

Ligamentum flavum hypertrophy (LFH) is the main physiological and pathological mechanism of lumbar spinal canal stenosis (LSCS). The specific mechanism for LFH has not been completely clarified. In this study, bioinformatic analysis, human ligamentum flavum (LF) tissues collection and analysis, and in vitro and in vivo experiments were conducted to explore the effect of decorin (DCN) on LFH pathogenesis. Here, we found that TGF-ß1, collagen I, collagen III, α-SMA and fibronectin were significantly upregulated in hypertrophic LF samples. The DCN protein expression in hypertrophic LF samples was higher than that in non-LFH samples, but the difference was not significant. DCN inhibited the expression of TGF-ß1-induced fibrosis-associated proteins in human LF cells, including collagen I, collagen III, α-SMA, and fibronectin. ELISAs showed that TGF-ß1 can upregulate PINP and PIIINP in the cell supernatant, and this effect was inhibited after DCN administration. Mechanistic studies revealed that DCN suppressed TGF-ß1-induced fibrosis by blocking the TGF-ß1/SMAD3 signaling pathway. In addition, DCN ameliorated mechanical stress-induced LFH in vivo. In summary, our findings indicated that DCN ameliorated mechanical stress-induced LFH by antagonizing the TGF-ß1/SMAD3 signaling pathway in vitro and in vivo. These findings imply that DCN is a potential therapeutic candidate for ligamentum flavum hypertrophy.

Pipkin type III femoral head fracture: which treatment strategy can be recommended?

BACKGROUND: Pipkin type III femoral head fractures are relatively rare injuries. Few studies have explored and described the treatment and outcomes of Pipkin type III femoral head fractures. The purpose of this study was to evaluate the efficacy of open reduction and internal fixation (ORIF) in treating Pipkin type III femoral head fractures. METHODS: We retrospectively reviewed 12 patients with Pipkin type III femoral head fractures who underwent ORIF from July 2010 and January 2018. The complications and reoperations were recorded. The visual analog scale (VAS) pain score, Harris hip score (HHS), Thompson-Epstein criteria, and SF-12 score [including the physical component summary (PCS) and the mental component summary (MCS)] were used for functional assessment. RESULTS: Among the 12 patients, ten were males and two were females, with a mean age of 34.2 ± 11.9 years. The median follow-up time was 6 years (range 4-8 years). Five patients (42%) developed osteonecrosis of the femoral head, and one patient (8%) developed nonunion. These six patients (50%) underwent total hip arthroplasty (THA). One patient (8%) developed heterotopic ossification and underwent ectopic bone excision; this patient also presented with post-traumatic arthritis. The mean final VAS pain score and HHS were 4.1 ± 3.1 points and 62.8 ± 24.4 points, respectively. According to the Thompson-Epstein criteria, there was one patient (8%) with excellent, four patients (33%) with good, one patient (8%) with fair, and six patients (50%) with poor outcomes. The PCS score and MCS score were 41.7 ± 34.7 points and 63.2 ± 14.5 points, respectively. CONCLUSION: Limited by the high incidence of osteonecrosis of the femoral head, it is difficult to achieve satisfactory functional outcomes when treating Pipkin type III femoral head fractures using ORIF, and a primary THA may be considered. However, for younger patients, considering the survivorship of prosthesis, ORIF may be recommended with the proviso that the patient is fully informed of the high complication rate associated with this procedure. LEVEL OF EVIDENCE: IV.

A comprehensive analysis of single-cell RNA transcriptome reveals unique SPP1+ chondrocytes in human osteoarthritis.

Osteoarthritis (OA) has become the most common degenerative disease in the world, which brings a serious economic burden to society and the country. Although epidemiological studies have shown that the occurrence of osteoarthritis is associated with obesity, sex, and trauma, the biomolecular mechanisms for the development and progression of osteoarthritis remain ambiguous. Several studies have drawn a connection between SPP1 and osteoarthritis. SPP1 was first found to be highly expressed in osteoarthritic cartilage, and later more studies have shown that SPP1 is also highly expressed in subchondral bone and synovial in OA patients. However, the biological function of SPP1 remains unclear. Single-cell RNA sequencing (scRNA-seq) is a novel technique that reflects gene expression at the cellular level, making it better depict the state of different cells than ordinary transcriptome data. However, most of the existing chondrocyte scRNA-seq studies focus on the occurrence and development of OA chondrocytes and lack analysis of normal chondrocyte development. Therefore, to better understand the mechanism of OA, scRNA-seq analysis of a larger cell volume containing normal and osteoarthritic cartilage is of great importance. Our study identifies a unique cluster of chondrocytes characterized by high SPP1 expression. The metabolic and biological characteristics of these clusters were further investigated. Besides, in animal models, we found that the expression of SPP1 is spatially heterogeneous in cartilage. Overall, our work provides novel insight into the potential role of SPP1 in OA, which sheds light on understanding the role of SPP1 in OA, promoting the progress of the treatment and prevention in the field of OA.

Dioscin alleviates the progression of osteoarthritis: an in vitro and in vivo study.

Osteoarthritis (OA) is a common joint disease and is the main cause of physical disability in the elderly. Currently, there is no adequate therapeutic strategy to reverse the progression of OA. Many natural plant extracts have received attention in the treatment of OA due to their potential anti-inflammatory properties, and reduced incidence of adverse events. Dioscin (Dio), a natural steroid saponin, has been demonstrated to inhibit the release of inflammatory cytokines in mouse and rat models of various diseases, and has a protective effect in chronic inflammatory diseases. However, whether Dio alleviates OA progression remains to be explored. In this research, our purposes were to investigate the therapeutic potential of Dio in OA. The results demonstrated that Dio exerted anti-inflammatory effects by repressing NO, PGE2, iNOS and COX-2. Moreover, the application of Dio could repress IL-1ß-induced overexpression of matrix metalloproteinases (MMPs, including MMP1, MMP3, and MMP13) and ADAMTS-5, and improve the synthesis of collagen II and aggrecan, which contribute to the maintenance of chondrocyte matrix homeostasis. The underlying mechanism involved the inhibition of the MAPK and NF-κB signaling pathways by Dio. Furthermore, the treatment of Dio significantly improved the pain behaviors of rat OA models. The in vivo study revealed that Dio could ameliorate cartilage erosion and degradation. These results collectively indicate that Dio can be used as a promising and effective agent for the therapy of OA.

Is 3D-printed Titanium cage a reliable option for 3-level anterior cervical discectomy and fusion in treating degenerative cervical spondylosis?

Background: To assess the clinical and radiographical outcomes of 3-level anterior cervical discectomy and fusion (ACDF) with a 3D-printed titanium cage in treating degenerative cervical spondylosis. Methods: In this study, 25 patients with degenerative cervical spondylosis who underwent 3-level ACDF using a 3D-printed titanium cage from March 2019 to June 2021 were retrospectively enrolled. The patient-reported outcome measures (PROMs) were evaluated by visual analog scale (VAS) for the neck (VAS-neck) and arm pain (VAS-arm), Neck Disability Index (NDI) score, Japanese Orthopedic Association (JOA) score, SF-12 concise health survey, and the Odom criteria. The radiographical parameters, including C2-C7 lordosis, segmental angle, segmental height, and subsidence, were assessed. The mean duration of follow-up was 25.6 months. Results: Bony fusion was achieved in all patients (100%). In three patients (12%) mild dysphagia was observed during the follow-up. The VAS-neck, VAS-arm, NDI score, JOA score, SF-12 score, C2-C7 lordosis, and segmental angle improved noticeably at the latest follow-up. Based on the Odom criteria, 22 patients (88%) reported satisfactory (excellent or good). The mean loss of C2-C7 lordosis and segmental angle between the immediate postoperative and the latest follow-up values were 1.6° ± 0.5° and 1.1° ± 0.5°, respectively. The mean subsidence was 0.9 ± 0.6 mm. Conclusion: In patients with multi-level degenerative cervical spondylosis, 3-level ACDF using the 3D-printed titanium cage can effectively relieve the symptoms, stabilize the spine, and restore segmental height and cervical curvature. It is proven to be a reliable option for patients with 3-level degenerative cervical spondylosis. However, a future comparative study involving a larger population and longer follow-up time may be required to further evaluate the safety, efficacy and outcomes of our preliminary results.

BMP7 ameliorates intervertebral disc degeneration in type 1 diabetic rats by inhibiting pyroptosis of nucleus pulposus cells and NLRP3 inflammasome activity.

BACKGROUND: Accumulating evidence indicates that intervertebral disc degeneration (IDD) is associated with diabetes mellitus (DM), while the underlying mechanisms still remain elusive. Herein, the current study sought to explore the potential molecular mechanism of IDD in diabetic rats based on transcriptome sequencing data. METHODS: Streptozotocin (STZ)-induced diabetes mellitus type 1 (T1DM) rats were used to obtain the nucleus pulposus tissues for transcriptome sequencing. Next, differentially expressed genes (DEGs) in transcriptome sequencing data and GSE34000 microarray dataset were obtained and intersected to acquire the candidate genes. Moreover, GO and KEGG enrichment analyses were performed to analyze the cellular functions and molecular signaling pathways primarily regulated by candidate DEGs. RESULTS: A total of 35 key genes involved in IDD of T1DM rats were mainly enriched in the extracellular matrix (ECM) and cytokine adhesion binding-related pathways. NLRP3 inflammasome activation promoted the pyroptosis of nucleus pulposus cells (NPCs). Besides, BMP7 could affect the IDD of T1DM rats by regulating the inflammatory responses. Additionally, NPCs were isolated from STZ-induced T1DM rats to illustrate the effects of BMP7 on IDD of T1DM rats using the ectopic expression method. Both in vitro and in vivo experiments validated that BMP7 alleviated IDD of T1DM rats by inhibiting NLRP3 inflammasome activation and pyroptosis of NPCs. CONCLUSION: Collectively, our findings provided novel mechanistic insights for understanding of the role of BMP7 in IDD of T1DM, and further highlighted BMP7 as a potential therapeutic target for preventing IDD in T1DM.

Ferrostatin-1 Inhibits Toll-Like Receptor 4/NF-κB Signaling to Alleviate Intervertebral Disc Degeneration in Rats.

Ferrostatin-1 (Fer-1), an inhibitor of ferroptosis, is implicated in intervertebral disc degeneration (IDD). The current study explored the role of Fer-1 in IDD via the toll-like receptor 4 (TLR4)/NF-κB signaling pathway. IDD-related gene expression microarray GSE124272 and high-throughput sequencing data set GSE175710 were obtained through the Gene Expression Omnibus database. Differentially expressed genes in IDD were identified, followed by implementation of protein-protein interaction network analysis and receiver operating characteristic curve analysis. The main pathways in IDD were obtained through Gene Ontology and Kyoto Encyclopedia of Genes and Genomes functional analyses, and target genes of Fer-1 were obtained through PubChem and PharmMapper websites. Finally, GPX4, FTH, and TLR4 expression was determined in a IDD rat model. Three key co-expression modules involved in IDD were obtained through Weighted Gene Co-Expression Network Analysis. Thirteen differentially expressed genes were found to be associated with IDD, and eight key genes (TLR4, BCL2A1, CXCL1, IL1R1, NAMPT, SOCS3, XCL1, and IRAK3) were found to affect IDD. These eight key genes had the diagnostic potential for IDD. The NF-κB signaling pathway was shown to play a predominant role in IDD development. Network pharmacologic analysis indicated a role of Fer-1 in suppressing ferroptosis and ameliorating IDD via the TLR4/NF-κB signaling pathway, which was verified by an in vivo animal experiment. The study showed that Fer-1 down-regulates TLR4 to inactivate NF-κB signaling pathway, suppressing ferroptosis and ultimately alleviating IDD in rats.

Is Ankle Arthrodesis With an Ilizarov External Fixator an Effective Treatment for Septic Ankle Arthritis? A Study With a Minimum of 6 Years of Follow-up.

BACKGROUND: Septic ankle arthritis is a devastating clinical problem with a high potential for permanent disability and amputation. Successful treatment of septic ankle arthritis remains a challenge for the surgeon and patient. Ankle arthrodesis combined with radical debridement may be an effective option to eradicate infection and salvage the limb. Although numerous fusion methods have been proposed, there is controversy about the most effective technique. QUESTIONS/PURPOSES: At a minimum follow-up of 6 years after ankle arthrodesis performed using an Ilizarov external fixator, we asked, (1) In what proportion of patients was bony fusion achieved? (2) What complications were observed, and what reoperations were performed in these patients? (3) How much did patient-reported outcomes improve from before surgery to the most recent follow-up in this group? METHODS: Between April 2010 to March 2015, we treated 59 patients for septic ankle arthritis. Of those, we considered patients who were at least 18 years of age with irreversible destruction of the joint as potentially eligible. During that time period, all patients met the prespecified criteria and were treated with ankle arthrodesis using an Ilizarov external fixator. Two percent (one of 59) of patients were excluded because they died in the second year after surgery for reasons unrelated to the procedure, and another 7% (four of 59) of patients were excluded because they were lost before the minimum study follow-up interval of 6 years. Finally, 92% (54 of 59) of patients were analyzed at a mean follow-up time of 9 ± 1 years. A total of 61% (33 of 54) were men, and they had a mean age of 48 ± 12 years. Forty-six percent (25 of 54) of patients were smokers, and 13% (seven of 54) of patients had Type 2 diabetes mellitus. All patients received radical debridement and primary arthrodesis with an Ilizarov external fixator, followed by antibiotic therapy. Postoperatively, patients were instructed to perform lower extremity functional exercises and external fixator care; weightbearing ambulation as tolerated was encouraged as early as possible. Fusion was assessed with a radiographic review that was performed by an individual who was not involved in the surgical care of these patients. We defined bony fusion as continuous trabeculae and complete cortical bridging in the fusion interface achieved before 9 months; delayed union was defined as fusion achieved by 9 to 12 months; and nonunion was defined as patients in whom fusion was not achieved by 12 months. Complications and reoperations were tallied through a record review that was performed by an individual who was not involved in the surgical care of these patients. We defined complications as any deviation from the expected postoperative course. We used the American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, the VAS active pain score, and the SF-12 questionnaire (including the physical component summary [PCS] score and mental component summary [MCS] score) to assess patient-reported outcomes. The minimum clinically important difference (MCID) for the AOFAS score was 30 points of 100, the MCID for the VAS active pain score was 2 points of 10, and the MCID of PCS and MCS scores was 7 points and 9 points, respectively. RESULTS: Primary bony fusion was achieved in 94% (51 of 54) of patients. Delayed union was found in 2% (one of 54) of patients. Nonunion was found in 6% (three of 54); one of these patients underwent autologous bone grafting during revision, and bony fusion was ultimately achieved. Final bony fusion was achieved in 96% (52 of 54) of patients. Recurrent infection was found in 2% (one of 54). The median (range) AOFAS score improved from 28 points (8 to 59) before surgery to 80 points (52 to 86) at the most recent follow-up (median difference 52; p < 0.001). The median (range) VAS active pain score decreased from 8 points (6 to 9) before surgery to 2 points (0 to 5) at the most recent follow-up (median difference -6; p < 0.001). For the Short Form 12-item score, the median (range) PCS score improved from 0 points (0 to 30) before surgery to 70 points (40 to 95) at the most recent follow-up (median difference 70; p < 0.001), and the median (range) MCS score improved from 46 points (21 to 75) before surgery to 75 points (50 to 92) at the most recent follow-up (median difference 29; p < 0.001). CONCLUSION: Ankle arthrodesis with Ilizarov external fixation might eradicate an infection and restore foot function in patients with septic ankle arthritis. However, patients should be fully informed of the complications related to the external fixator, such as pin-tract infections, recurrent infection, and nonunion. Standardized and professional pin care is important. Additionally, because Ilizarov external fixators can be inconvenient to the patients' daily lives, future studies should explore how psychologic support affects patients who undergo ankle arthrodesis with these devices. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Flavokawain A alleviates the progression of mouse osteoarthritis: An in vitro and in vivo study.

Osteoarthritis (OA) is one of the most prevalent chronic degenerative joint diseases affecting adults in their middle or later years. It is characterized by symptoms such as joint pain, difficulty in movement, disability, and even loss of motion. Moreover, the onset and progression of inflammation are directly associated with OA. In this research, we evaluated the impact of Flavokawain A (FKA) on osteoarthritis. In-vitro effects of FKA on murine chondrocytes have been examined using cell counting kit-8 (CCK-8), safranin o staining, western blot, immunofluorescence staining, senescence ß-galactosidase staining, flow cytometry analysis, and mRFP-GFP-LC3 adenovirus infection. An in-vivo model of destabilization of the medial meniscus (DMM) was employed to investigate FKA's effect on OA mouse. An analysis of bioinformatics was performed on FKA and its potential role in OA. It was observed that FKA blocked interleukin (IL)-1ß-induced expression of inflammatory factors, i.e., cyclooxygenase-2 (COX2) and inducible nitric oxide synthase (iNOS) in chondrocytes. In addition, FKA also downregulated the catabolic enzyme expression, i.e., aggrecanase-2 (ADAMTS5) and matrix metalloproteinases (MMPs), and helped in the upregulation of the anabolic protein expression, i.e., type II collagen (Col2), Aggrecan, and sry-box transcription factor 9 (SOX9). Moreover, FKA ameliorated IL-1ß-triggered autophagy in chondrocytes, and it was observed that the FKA causes anti-inflammatory effects by the mitogen-activated protein kinase (MAPK) and phosphoinositide-3-kinase/Akt/mammalian target of rapamycin (PI3K/AKT/mTOR) signaling pathways inhibition. The results of immunohistochemical analysis and microcomputed tomography from the in vivo OA mouse model confirmed the therapeutic effect of FKA. Finally, we assessed the anti-arthritic impacts of FKA by conducting in vivo and in vitro analyses. We concluded that FKA can be employed as a useful therapeutic agent for OA therapy, but the findings require needs further clinical investigation.

Mesenchymal stem cells shuttling miR-503 via extracellular vesicles enhance glioma immune escape.

Glioma is emerging as an aggressive type of glioma characterized by invasive growth pattern and dismal oncologic outcomes. microRNAs (miRNAs) have been attracting research attention in tumorigenesis. Herein, the aim of the current investigation was to explore the functional role of mesenchymal stem cells (MSCs)-derived extracellular vesicles (EVs) containing miR-503 in glioma. The glioma tissues and corresponding normal brain tissues were collected from patients with glioma, followed by quantification of miR-503, kinesin family member 5A (KIF5A) and interleukin-7 (IL-7). EVs were isolated from bone marrow MSCs and identified by transmission electron microscope and nanoparticle tracking analysis. EVs from miR-503 mimic-transfected MSCs, miR-503 agomir,, oe-KIF5A, or sh-IL-7 was delivered into glioma cells to determine their effects on biological behaviors of glioma and T cells as well as the release of immunosuppressive factors. Lastly, a mouse model of glioma was developed to validate the function in vivo. miR-503 was expressed at a high level in glioma tissues while KIF5A was poorly expressed and targeted by miR-503. Furthermore, miR-503 loaded in MSC-EVs or upregulated miR-503 was demonstrated to facilitate glioma cell proliferation, migration and invasion accompanied by promoted release of immunosuppressive factors. Effects of overexpressed KIF5A on T cell behavior modulation were dependent on the IL-7 signaling pathway. Such results were reproduced in mice with glioma. Collectively, the discovery of miR-503 incorporated in MSC-EVs being a regulator that controls immune escape in glioma provides a novel molecular insight that holds promises to develop therapeutic strategies against glioma.

miR-31 from Mesenchymal Stem Cell-Derived Extracellular Vesicles Alleviates Intervertebral Disc Degeneration by Inhibiting NFAT5 and Upregulating the Wnt/ß-Catenin Pathway.

In this study, we explored the regulatory mechanism of intervertebral disc degeneration (IDD) that involves miR-31 shuttled by bone marrow mesenchymal stem cell-derived extracellular vesicles (BMSC-EVs) and its downstream signaling molecules. Nucleus pulposus cells (NPCs) were isolated and treated with TNF-α to simulate IDD in vitro. The TNF-α-exposed NPCs were then cocultured with hBMSCs or hBMSC-EVs in vitro to detect the effects of hBMSC-EVs on NPC viability, apoptosis, and ECM degradation. Binding between miR-31 and NFAT5 was determined. A mouse model of IDD was prepared by vertebral disc puncture and injected with EVs from hBMSCs with miR-31 knockdown to discern the function of miR-31 in vivo. The results demonstrated that hBMSC-EVs delivered miR-31 into NPCs. hBMSC-EVs enhanced NPC proliferation and suppressed cell apoptosis and ECM degradation, which was associated with the transfer of miR-31 into NPCs. In NPCs, miR-31 bound to the 3'UTR of NFAT5 and inhibited NFAT5 expression, leading to activation of the Wnt/ß-catenin pathway and thus promoting NPC proliferation and reducing cell apoptosis and ECM degradation. In addition, miR-31 in hBMSC-EVs alleviated the IDD in mouse models. Taken together, miR-31 in hBMSC-EVs can alleviate IDD by targeting NFAT5 and activating the Wnt/ß-catenin pathway.