Landscape of the Lumbar Cartilaginous End Plate Microbiota and Metabolites in Patients with Modic Changes.

BACKGROUND: Modic changes (MCs), vertebral end plate and bone marrow damage observed by magnetic resonance imaging, are an independent risk factor for low back pain. The compositions of and interaction between microbiota and metabolites in the lumbar cartilaginous end plates (LCEPs) of patients with MCs have not been identified. METHODS: Patients with lumbar disc degeneration who were undergoing lumbar spinal fusion surgery were recruited between April 2020 and April 2021. LCEPs were collected for 16S rRNA sequencing and liquid chromatography-mass spectrometry (LC/MS)-based targeted metabolomic profiling. Of the 54 patients recruited, 24 had no MCs and 30 had changes classified as Modic type 2 or 3. The primary goal was to identify specific genera of microbiota associated with MCs, and secondary goals included investigating differences in metabolites between patients with and without MCs and exploring the correlation between these metabolites and microorganisms. RESULTS: Investigation of the microbiota community structure revealed that both alpha diversity and beta diversity were significantly different between patients with and without MCs, and the abundances of 26 genera were significantly different between these 2 groups. Metabolomic analysis revealed that 26 metabolites were significantly different between the 2 groups. The unsaturated fatty acid pathway was found to be the main pathway related to MCs. Multiomic correlation analysis suggested that Caulobacteraceae (unclassified) and Mycobacterium, Clostridium, Blautia, and Bifidobacterium at the genus level were linked to dysregulation of fatty acid metabolism, contributing to the pathogenesis of MCs. CONCLUSIONS: Our study represents a foundational effort to examine the landscape of the microbiota and metabolites in patients with MCs, informing future studies on the pathogenesis of and targeted therapy for MCs. LEVEL OF EVIDENCE: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Low-dose Lipopolysaccharide Alleviates Spinal Cord Injury-induced Neuronal Inflammation by Inhibiting microRNA-429-mediated Suppression of PI3K/AKT/Nrf2 Signaling.

This study investigated the impact of low-dose lipopolysaccharide (LPS) on spinal cord injury (SCI) and the potential molecular mechanism. Rats were randomly assigned to four groups: Sham, SCI, SCI + LPS, and SCI + LPS + agomir. Allen's weight-drop method was used to establish an in vivo SCI model. The Basso Bcattie Bresnahan rating scale was employed to monitor locomotor function. An in vitro SCI model was constructed by subjecting PC12 cells to oxygen and glucose deprivation/ reoxygenation (OGD/R). Enzyme-linked immunosorbent assay (ELISA) was applied for the determination interleukin (IL)-1ß and IL-6. The dual luciferase reporter assay was used to validate the targeting of microRNA (miR)-429 with PI3K. Immunohistochemical staining was used to assess the expression of PI3K, phosphorylated AKT and Nrf2 proteins. The Nrf2-downstream anti-oxidative stress proteins, OH-1 and NQO1, were detected by western blot assay. MiR-429 expression was detected by fluorescence in situ hybridization and real-time quantitative reverse transcription PCR. In vitro, low-dose LPS decreased miR-429 expression, activated PI3K/AKT/Nrf2, inhibited oxidative stress and inflammation, and attenuated SCI. MiR-429 was found to target and negatively regulate PI3K. Inhibition of miR-429 suppressed low-dose LPS-mediated oxidative stress and inflammation via activation of the PI3K/AKT/Nrf2 pathway. In vivo, miR-429 was detectable in neurons. Inhibition of miR-429 blocked low-dose LPS-mediated oxidative stress and inflammation via activation of the PI3K/AKT/Nrf2 pathway. Overall, low-dose LPS was found to alleviate SCI-induced neuronal oxidative stress and inflammatory response by down-regulating miR-429 to activate the PI3K/AKT/Nrf2 pathway.

A Pain That is Easily Overlooked: Referred Pain Caused by OVCF.

Purpose: The objective of this study was to analyze the clinical characteristics and the therapeutic effects of treatment at our spinal center in OVCF patients associated with referred pain. The underlying goals were to deepen the understanding of referred pain caused by OVCFs, improve the currently low early diagnosis rate of OVCFs, and improve the effectiveness of treatment. Methods: The patients who had referred pain from OVCFs and met the inclusion criteria were retrospectively analyzed. All patients were treated with percutaneous kyphoplasty (PKP). Visual analog scale (VAS) scores and Oswestry Disability Index (ODI) were used to evaluate the therapeutic effect at different time points. Results: There were 11 males (19.6%) and 45 females (80.4%). Their corresponding mean bone mineral density (BMD) value was -3.3 ± 0.4. The regression coefficient of BMD in the linear regression equation was -4.51 (P<0.001). According to the classification system for referred pain in OVCFs, there were 27 cases of type A (48.2%), 12 cases of type B (21.2%), 8 cases of type C (14.3%), 3 cases of type D (5.4%), and 6 cases of type E (10.7%). All patients were followed up for at least 6 months, and both VAS scores and ODI were found to be significantly better postoperatively than preoperatively (P<0.001). There was no significant difference in VAS scores and ODI between different types preoperatively or 6 months postoperatively (P > 0.05). Within each type, there were significant differences in VAS scores and ODI between the pre- and postoperative timepoints (P < 0.05). Conclusion: Attention should be paid to referred pain in OVCF patients, which is not uncommon in clinical practice. Our summary of the characteristics of referred pain caused by OVCFs can improve the early diagnosis rate of OVCFs patients and provide a reference for their prognosis after PKP.

C3AR1 mRNA as a Potential Therapeutic Target Associates With Clinical Outcomes and Tumor Microenvironment in Osteosarcoma.

Objective: Targeting cancer-specific messenger RNAs (mRNAs) may offer novel insights into therapeutic strategies in osteosarcoma. This study aimed to discover possible osteosarcoma-specific mRNA and probe its biological functions. Methods: Based on mRNA-seq data from the TARGET database, stromal and immune scores were estimated for each osteosarcoma sample via the ESTIMATE algorithm. Stromal and immune mRNAs were obtained via integration of differentially expressed mRNAs between high and low stromal / immune score groups. Among hub and prognostic mRNAs, C3AR1 mRNA was focused and its prognostic value was assessed. The associations between C3AR1 mRNA and immune cells were analyzed via the CIBERSORT algorithm. Its expression was verified in osteosarcoma tissues and cells by RT-qPCR and western blot. The functions of C3AR1 were investigated by a series of experiments. Results: Low stromal and immune scores were both indicative of unfavorable outcomes for osteosarcoma patients. Eighty-eight up-regulated and seven down-regulated stromal and immune mRNAs were identified. Among 30 hub mRNAs, low expression of C3AR1 mRNA indicated worse outcomes than its high expression. There was a lower mRNA expression of C3AR1 in metastatic than non-metastatic osteosarcoma. C3AR1 mRNA was closely correlated to various immune cells such as macrophages. C3AR1 was verified to be down-regulated in osteosarcoma tissues and cells. Its overexpression suppressed proliferation, migration and invasion and induced apoptosis in osteosarcoma cells. Conclusion: C3AR1 mRNA could be a promising therapeutic target for osteosarcoma, linked with prognosis and tumor microenvironment.

MiR-374a Activates Wnt/ß-Catenin Signaling to Promote Osteosarcoma Cell Migration by Targeting WIF-1.

MiR-374a was proved to take part in the initiation and development of several cancers. However, the molecular mechanism of miR-374a in osteosarcoma (OS) cells remains unclear. The aim of our research was to investigate the role of miR-374a in OS cells migration and clarify the potential mechanisms. Quantitative real-time PCR (qRT-PCR) and western blot analysis were applied to evaluate the expression of miR-374a and Wnt inhibitory factor-1 (WIF-1). Bioinformatical methods and luciferase reporter assay were carried out to predict and confirm the combination of miR-374a and WIF-1. Transwell and wound healing assays were performed to detect the migration capacity of OS cells. Lithium chloride (LiCl) was used to investigate the role of LiCl-activated Wnt/ß-catenin signaling pathway in regulating cell migration. Our studies revealed that miR-374a was up-regulated whereas WIF-1 was down-regulated in OS cells. Besides, WIF-1 was the target of miR-374a by performing luciferase reporter assay. By transfection of miR-374a inhibitor and/or WIF-1 siRNA to OS cells, we found that miR-374a promoted the migration of OS cells. In addition, the inhibition of WIF-1 abolished the miR-374a inhibitor-induced migration suppression of OS cells. LiCl experiment revealed that miR-374a promoted OS cells migration by regulating Wnt/ß-catenin signaling. In conclusion, miR-374a promotes OS cells migration by activating Wnt/ß-catenin signaling pathway via targeting WIF-1.

Remove orthopedic fracture implant with minimal invasive surgery is good for the patient's early rehabilitation.

To explore the fact that minimal invasive osteosynthesis surgery could promote patient rehabilitate quickly. Patients needed to remove fracture fixation plates and screws in clavicle/femur/tibia and fibular bones were totally divided into two groups (conventional surgery group and minimal invasive surgery group). The operation time, intra-operative blood loose, post-operation 48 hours analgesic need, VAS score of 24-hours and 72-hours post-operation, post operation incision healing conditions, incision infection, patients' satisfaction about incision scar, and resting days were measured. Patients in the minimal invasive surgery group were satisfied with their scar condition than the conventional surgery group. There were no much difference between conventional surgery group and minimal invasive surgery group in operation time (46.3±10.2 minutes Vs 48.0±11.8 minutes) (P>0.05) and the blood lose in these two groups were 4 ml Vs 47.4±20.1 ml (P>0.05), respectively. There were no screws broken in both groups and all the implants were removed out successfully. Remove four limb fracture fixation implant with minimal invasive surgery is good for patients' early rehabilitation.