Intervertebral disc degeneration (IDD) development is regulated by miRNA, including inflammatory reactions, cell apoptosis, and degradation of extracellular matrix. Nucleus pulposus cells apoptosis has a absolute influence in the development of IDD. This experiment explores the mechanism of miR-328-5p regulating IDD. Through the analysis of miRNA and mRNA microarray database, we screened the target genes miR-328-5p and WWP2. We verified the expression of miR-328-5p, WWP2, and related apoptotic genes in normal and degenerative nucleus pulposus tissues by qRT-PCR. The expressions of WWP2, Bcl-2, and Bax were detected by qRT-PCR and western blot after transfection to nucleus pulposus cell. The nucleus pulposus cell proliferation and apoptosis after transfection were confirmed by CCK8 and flow cytometry. Luciferase reporter assay and bioinformatics analyzed the targeting relationship between miR-328-5p and WWP2. Firstly, the qRT-PCR experiments confirmed the significant increase of miR-328-5p expression, while significant reduction of WWP2 in a degenerative tissues compared to the normal tissues. Surprisingly, miR-328-5p expression was positively, while that of WWP2 negatively correlated with the degeneration grade of IDD. And we also identified the high expression of Bax and Caspase3, while low expression of Bcl-2 in a degenerative tissues. After miR-328-5p mimic transfected into nucleus pulposus cell, qRT-PCR and western blot confirmed that WWP2 and Bcl-2 expressions were downregulated, while Bax and Caspase3 expressions were upregulated, and the same results were obtained by knocking down WWP2. CCK8 and flow cytometry confirmed that miR-328-5p inhibited the proliferation and induced apoptosis of nucleus pulposus cells. WWP2 is a target gene of miR-328-5p by bioinformatics and luciferase reporter assay. In summary, miR-328-5p targets WWP2 to regulate nucleus pulposus cells apoptosis and then participates in the development of IDD. Furthermore, this study may provide new references and ideas for IDD treatment.

The pathogenesis of intervertebral disc degeneration (IDD) is still unclear. It has been shown that the pathological process of IDD is most closely related to inflammation of nucleus pulposus cells (NPCs), in which inflammatory factors play an important role. Exosomes are the main paracrine mediators and are microvesicles with biological functions similar to those of the cells from which they are derived. Studies have shown that bone mesenchymal stem cells (BMSCs) can inhibit apoptosis of NPCs by sending exosomes as anti-inflammatory and antioxidant, which has been proved to be effective on IDD. However, the specific mechanism of inhibiting apoptosis of NPCs is still unclear. In our study, BMSC-derived exosomes (BMSC-Exo) were isolated from the BMSC culture medium, and their antiapoptotic effects were evaluated in cells and rat models to explore the possible mechanisms. We observed that BMSC-Exo promotes autophagy in NPCs and inhibits the release of inflammatory factors such as IL-1β and TNF-α in LPS-treated NPCs and inhibits apoptosis in NPCs. Further studies showed that BMSC-Exo inhibited the Akt-mTOR pathway. Intramuscular injection of BMSC-Exo alleviates disc degeneration in rat IDD models. In conclusion, our results suggest that BMSC-Exo can reduce NPC apoptosis and alleviate IDD by promoting autophagy by inhibiting the Akt-mTOR pathway. Our study confers a promising therapeutic strategy for IDD.

This study aims to analysis the efficacy of the 3D printing percutaneous guide template in combination with the pointed lotus-style regulator in percutaneous pedicle screw fixation. 60 thoracolumbar fractures patients receiving percutaneous pedicle screw fixation (PPSF) were enrolled and randomly divided into 3 groups. Patients in Group A received traditional PPSF, while patients in Group B received PPSF with flat end lotus-style regulator and patients in Group C received PPSF with pointed lotus-style regulator. The experimental results showed that the highest number of pedicle screw successfully inserted by the first time was in group C, while lowest in group A (P < 0.05). The total time of fluoroscopy and operation were lower in group C, and higher in group A (P < 0.05). VAS and ODI scores were all lower after surgery than before surgery in 3groups. VAS and ODI scores were lower in group B and C, compared with group A at day 1, 7 after surgery (P < 0.05). KA decreased significantly in 3 groups after surgery and no difference in KA change between 3 groups (P > 0.05). Taken together, Application of the 3D printing guide template in combination with pointed lotus-style regulator improved the accuracy of pedicle insertion.Trial registration: ClinicalTrials.gov Identifier: NCT04980131. Registered 18/07/2021.

This study aims to analysis the efficacy of the 3D printing percutaneous guide template in combination with the pointed lotus-style regulator in percutaneous pedicle screw fixation.60thoracolumbar fractures patients receiving percutaneous pedicle screw fixation (PPSF) were enrolled and randomly divided into 3 groups. Patients in Group A received traditional PPSF, while patients in Group B received PPSF with flat end lotus-style regulator and patients in Group C received PPSF with pointed lotus-style regulator. The experimental results showed that the highest number of pedicle screw successfully inserted by the first time was in group C, while lowest in group A (P<0.05). The total time of fluoroscopy and operation were lower in group C, and higher in group A (P<0.05). VAS and ODI scores were all lower after surgery than before surgery in 3groups. VAS and ODI scores were lower in group B and C, compared with group A at day 1 ,7 after surgery (P<0.05). KA decreased significantly in 3 groups after surgery and no difference in KA change between 3 groups (P>0.05). Taken together, Application of the 3D printing guide template in combination with pointed lotus-style regulator improved the accuracy of pedicle insertion.Trial registration: ClinicalTrials.gov Identifier: NCT04980131. Registered 18/07/2021.