TSG-6 inhibits IL-1β-induced inflammatory responses and extracellular matrix degradation in nucleus pulposus cells by activating the PI3K/Akt signaling pathway

Fucoidan improves intestinal peristaltic function in rats with postoperative ileus

The effect of fucoidan on postoperative ileus (POI) has not been studied. In this study, how fucoidan ameliorates POI in a rat POI model was investigated. The results showed that in the model animals, when the first defecation time was prolonged, the amount of food consumed decreased, the small intestinal propulsion rate dramatically slowed, and the motility index (MI%) of the small intestine decreased. In vitro experiments revealed that the contractile response of small intestinal smooth muscle strips to carbachol (CCh) was reduced. Immunohistochemistry revealed evident macrophage infiltration in the intestinal muscularis. However, after oral pretreatment with fucoidan, the time to first defecation decreased, and food intake, the small intestinal propulsion rate, and MI% of the small intestine increased. Additionally, the contractile response of the intestinal strips to CCh became stronger, and macrophage infiltration decreased. Mechanistically, fucoidan alleviated POI by exerting anti-inflammatory and antioxidant effects as well as likely through the TrkB/ERK1/2/Akt signalling pathways. When POI occurred, the expression levels of inflammatory factors in the intestines significantly increased while the phosphorylation of TrkB, ERK1/2, and Akt significantly decreased; malondialdehyde (MDA) levels in the intestines increased but the levels of superoxide dismutase (SOD) and glutathione (GSH) decreased. In contrast, after pretreatment with fucoidan, the expression levels of inflammatory factors decreased; the phosphorylation levels of TrkB, ERK1/2, and Akt increased; the MDA level decreased; and SOD and GSH levels increased. Thus, fucoidan alleviated POI-induced impairment of rat intestinal motility through anti-inflammatory and antioxidant effects possibly associated with the TrkB/ERK1/2 and Akt signalling pathways.

Biomolecular therapies for chronic discogenic low back pain: A narrative review

Chronic low back pain caused by intervertebral disc (IVD) degeneration, also termed chronic discogenic low back pain (CD-LBP), is one of the most prevalent musculoskeletal diseases. Degenerative processes in the IVD, such as inflammation and extra-cellular matrix breakdown, result in neurotrophin release. Local elevated neurotrophin levels will stimulate sprouting and innervation of sensory neurons. Furthermore, sprouted sensory nerves that are directly connected to adjacent dorsal root ganglia have shown to increase microglia activation, contributing to the maintenance and chronification of pain. Current pain treatments have shown to be insufficient or inadequate for long-term usage. Furthermore, most therapeutic approaches aimed to target the underlying pathogenesis of disc degeneration focus on repair and regeneration and neglect chronic pain. How biomolecular therapies influence the degenerative IVD environment, pain signaling cascades, and innervation and excitability of the sensory neurons often remains unclear. This review addresses the relatively underexplored area of chronic pain treatment for CD-LBP and summarizes effects of therapies aimed for CD-LBP with special emphasis on chronic pain. Approaches based on blocking pro-inflammatory mediators or neurotrophin activity have been shown to hamper neuronal ingrowth into the disc. Furthermore, the tissue regenerative and neuro inhibitory properties of extracellular matrix components or transplanted mesenchymal stem cells are potentially interesting biomolecular approaches to not only block IVD degeneration but also impede pain sensitization. At present, most biomolecular therapies are based on acute IVD degeneration models and thus do not reflect the real clinical chronic pain situation in CD-LBP patients. Future studies should aim at investigating the effects of therapeutic interventions applied in chronic degenerated discs containing established sensory nerve ingrowth. The in-depth understanding of the ramifications from biomolecular therapies on pain (chronification) pathways and pain relief in CD-LBP could help narrow the gap between the pre-clinical bench and clinical bedside for novel CD-LBP therapeutics and optimize pain treatment.

Hyaluronic Acid Interacting Molecules Mediated Crosstalk between Cancer Cells and Microenvironment from Primary Tumour to Distant Metastasis

Hyaluronic acid (HA) is a prominent component of the extracellular matrix, and its interactions with HA-interacting molecules (HAIMs) play a critical role in cancer development and disease progression. This review explores the multifaceted role of HAIMs in the context of cancer, focusing on their influence on disease progression by dissecting relevant cellular and molecular mechanisms in tumour cells and the tumour microenvironment. Cancer progression can be profoundly affected by the interactions between HA and HAIMs. They modulate critical processes such as cell adhesion, migration, invasion, and proliferation. The TME serves as a dynamic platform in which HAIMs contribute to the formation of a unique niche. The resulting changes in HA composition profoundly influence the biophysical properties of the TME. These modifications in the TME, in conjunction with HAIMs, impact angiogenesis, immune cell recruitment, and immune evasion. Therefore, understanding the intricate interplay between HAIMs and HA within the cancer context is essential for developing novel therapeutic strategies. Targeting these interactions offers promising avenues for cancer treatment, as they hold the potential to disrupt critical aspects of disease progression and the TME. Further research in this field is imperative for advancing our knowledge and the treatment of cancer.

Silencing DDX3 Attenuates Interleukin-1β-Induced Intervertebral Disc Degeneration Through Inhibiting Pyroptosis

Intervertebral disc degeneration (IVDD) is a common disorder associated with chronic inflammation and cell death. In this study, an IVDD rat model was created through Interleukin-1β (IL-1β) injection. The degeneration of intervertebral disc tissues was assessed using magnetic resonance imaging (MRI), followed by hematoxylin and eosin (H&E) and terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL) staining. RNA sequencing was performed to identify differentially expressed genes (DEGs) between the IVDD model and control rats. The expression levels of DEGs (DEAD-box polypeptide 3 (DDX3), lysine-specific demethylase 5D (KDM5D), interferon-induced gene-1 (IFIT1), ribosomal protein S10 (RPS10), tenomodulin (TNMD), and pentraxin 3 (PTX3)) were measured by real-time quantitative polymerase chain reaction (RT-qPCR). The regulatory effect of DDX3 on pyroptosis in IL-1β-treated nucleus pulpous (NP) cells was assessed after transfection with siRNA of DDX3. A total of 601 DEGs were identified from the IVDD model rat, and were abundant in extracellular matrix (ECM) organization, ECM-receptor interaction, and inflammatory pathways, including the PI3K-Akt, TNF, and AMPK signaling pathways. DDX3, KDM5D, and IFIT1 levels were notably elevated, whereas RPS10, TNMD, and PTX3 levels were decreased in the IL-1β-induced IVDD rat model. Moreover, silencing DDX3 promoted cell proliferation and abolished IL-1β-induced cell apoptosis and pyroptosis. This study revealed the role of DDX3 in IVDD pyroptosis, providing potential target for IVDD management.

Visualizing the bibliometrics of the inflammatory mechanisms in intervertebral disc degeneration

OBJECTIVE

Intervertebral disc degeneration (IVDD) constitutes a crucial pathological foundation for spinal degenerative diseases (SDD) and stands as a primary contributor to both low back pain (LBP) and disability. The progression of IVDD is linked to structural and functional alterations in tissues, where an imbalance in the inflammatory microenvironment can induce extracellular matrix (ECM) degradation, senescence, and apoptosis. This imbalance is a key pathomechanism in the disease's development, gaining considerable attention in recent years. This study aims to conduct a bibliometric analysis of publications pertaining to the inflammatory mechanisms of IVDD to quantitatively assess current research hotspots and directions.

METHODS

In this study, we queried the Web of Science Core Collection (WOSCC) database covering the period from January 1, 2001, to November 7, 2023. Content in this area was analyzed and visualized using software such as Citespace, Vosviewer, and the bibliometrix package.

RESULTS

Findings indicate a consistent annual increase in the number of publications, highlighting the widespread attention garnered by research on the inflammatory mechanisms of IVDD. In terms of journal research, Spine emerged with the highest number of publications, along with significantly elevated total citations and average citations compared to other journals. Regarding country analysis, China led in the number of publications, while the USA claimed the highest number of citations and total link strength. Institutional analysis revealed Sun Yat-sen University as having the highest number of publications and total link strength, with Thomas Jefferson University securing the highest total citations. Author analysis identified Ohtori, S. with the highest number of publications, Risbud, M.V. with the highest number of citations, and Inoue, G. with the highest total link strength, all of whom have made significant contributions to the field's development. Citation and co-citation analyses indicated that highly cited documents primarily focused on classical studies exploring inflammatory mechanisms in IVDD pathogenesis. Keyword analysis showcased the ongoing research hotspot as the further investigation of mechanisms and treatment studies. Recent years have seen a shift towards exploring pyroptosis, necrotic apoptosis, autophagy, ferroptosis, oxidative stress, and bacterial infection, among other mechanisms. In terms of treatment, alongside traditional monomer, drug, and compound therapies for IVDD, research is increasingly concentrating on stem cell therapy, exosomes, hydrogels, and scaffolds.

CONCLUSION

This bibliometric analysis of research on inflammatory mechanisms in IVDD provides insights into the current status, hotspots, and potential future trends. These findings can serve as a valuable reference and guide for researchers in the field.

Astragaloside IV relieves IL-1β-induced human nucleus pulposus cells degeneration through modulating PI3K/Akt signaling pathway

BACKGROUND

Intervertebral disc degeneration (IDD) is a multifactorial disease that is associated with nucleus pulposus (NP) apoptosis and extracellular matrix (ECM) degeneration and inflammation. Astragaloside IV (AS IV) has antioxidant, free radical scavenging, anti-inflammatory and anti-apoptosis effects. This study was to investigate whether AS IV could inhibit IL-1β-mediated apoptosis of HNP cells and its possible signal transduction pathway.

METHODS

Human nucleus pulposus cells (HNPCs) were stimulated with AS IV or LY294002 (PI3K inhibitor), followed by exposure to IL-1β for 24 hours. CCK8, TUNEL analysis and flow cytometry, ELISA and Western blotting were used to analyze the effects of AS IV on cell proliferation, apoptosis, inflammation, ECM and PI3K/Akt pathway signaling path-related proteins in IL-1β-induced HNPCs.

RESULTS

Compared with IL-1β-induced HNPCs, AS IV could improve the proliferation activity and the expressions of Collagen II, Aggrecan and Bcl-2 proteins, inhibit the apoptosis rate, inflammation and Bax and cleaved caspase-3 protein expression, and increase the activity of PI3K/Akt pathway. LY294002 attenuated the protective effect of AS IV against IL-1β-induced HNPCs degeneration.

CONCLUSION

AS IV can inhibit IL-1β-induced HNPCs apoptosis inflammation and ECM degeneration by activating PI3K/Akt signaling pathway, which can be an effective drug to reduce disc degeneration.

Embelin protects against apoptosis and inflammation by regulating PI3K/Akt signaling in IL-1β-stimulated human nucleus pulposus cells

Embelin is a natural benzoquinone compound that displays a beneficial effect in various inflammatory-related diseases. However, the effect of embelin on degeneration of intervertebral disc (IDD), a chronic inflammatory disorder, has not been reported. This study was attempted to explore the therapeutic action of embelin on IDD in vitro. Network pharmacology analysis was performed for evaluating the link between embelin and IDD. The human nucleus pulposus cells (NPCs) were stimulated with IL-1β to induce inflammation. Cell viability of NPCs was assessed by CCK-8 assay. Western blotting was conducted to detect the expression levels of PI3K, p-PI3K, Akt, p-Akt, cleaved caspase-3, caspase-3, Bax, Bcl-2, p65 and p-p65. Apoptotic deaths of NPCs were examined by TUNEL assay. The production of COX-2, IL-6, IL-8, and TNF-α was examined by ELISA. It can be seen that 16 overlapping genes were selected from 109 possible targets of embelin and 342 possible targets of IDD. KEGG pathway enrichment analysis showed that the PI3K/Akt signaling pathway was a close link between embelin and IDD. We found that embelin dose-dependently improved the cell viability in IL-1β-stimulated NPCs. Embelin elevated the relative levels of p-PI3K/PI3K and p-Akt/Akt in IL-1β-stimulated NPCs. IL-1β induced a significant increase in apoptotic deaths of NPCs, which was attenuated by embelin treatment. IL-1β-induced alternations in expression levels of apoptotic-related proteins including cleaved caspase-3, Bax and Bcl-2 were prevented by embelin treatment. Pretreatment with LY294002 (an inhibitor of PI3K) reversed the inhibitory effect of embelin on IL-1β-induced apoptosis in NPCs. Embelin treatment caused inhibitory effects on the IL-1β-stimulated production of COX-2, IL-6, IL-8, and TNF-α, which were abolished by LY294002 treatment. Furthermore, embelin treatment prevented IL-1β-induced phosphorylation of p65 in NPCs, while LY294002 elevated the embelin-caused decrease in p-p65/p65 level. Overall, embelin protected human NPCs against IL-1β-stimulated apoptosis and inflammation by regulating the PI3K/Akt signaling pathway. These findings provided new ideas for the clinical usage of embelin in the prevention and treatment of IDD.