The IRF1/GBP5 axis promotes osteoarthritis progression by activating chondrocyte pyroptosis

Effects of infliximab infusion on clinical symptom scores and serum cytokines in patients with inflammatory bowel disease

BACKGROUND

Inflammatory bowel disease (IBD) is a chronic relapsing gastrointestinal disorder. Infliximab (INF) has shown good efficacy in IBD treatment, but its specific impact requires further exploration. This study aimed to assess the effects of intravenous INF on clinical symptom scores and serum cytokine levels in IBD patients.

METHODS

A retrospective review of 126 IBD patients treated with INF was conducted. Baseline data, Mayo scores, Crohn's Disease Activity Index (CDAI) scores at 6 and 12 months, and serum levels of TNF-α, IL-6, IL-10, and CRP were recorded. Correlations between disease activity scores and inflammatory markers were analyzed, and the relationship between baseline indicators and treatment efficacy was examined.

RESULTS

At 12 months, Mayo and CDAI scores, TNF-α, IL-6, and CRP levels were significantly reduced, while IL-10 levels increased. Disease activity scores positively correlated with TNF-α, IL-6, and IL-1β, and negatively with IL-10. Factors such as Crohn's disease subtype, age, high baseline CDAI or Mayo scores, elevated TNF-α, IL-6, CRP, and longer disease duration were associated with poorer outcomes (p < 0.05). Multivariate analysis identified disease type, high baseline disease activity, long disease duration, and elevated inflammatory markers as independent risk factors. Adverse reactions were infrequent, with no serious adverse events reported.

CONCLUSION

Intravenous INF effectively improves clinical symptoms and modulates inflammatory cytokines in IBD patients, with favorable safety and increasing efficacy over time. However, the limited sample size and lack of long-term data warrant further validation in larger, prospective multicenter studies.

Regulation of Exosomal miR-320d/FAM49B Axis by Guanylate Binding Protein 5 Promotes Cell Growth and Tumor Progression in Oral Squamous Cell Carcinoma

BACKGROUND

Guanylate binding protein 5 (GBP5) and exosomal miRNAs are involved in tumor progression. While several studies reveal the connection between GBP5 and exosomes for immune response and infection, this relationship in cancer, particularly in oral squamous cell carcinoma (OSCC), remains unexplored.

METHODS

The exosomal miRNA extracted from the cells was analyzed using next-generation sequencing. Bioinformatic tools were used to predict exosomal miRNA target genes. OSCC cell growth was verified by colony formation, cell viability, and cell cycle analysis. The Cancer Genome Atlas database was used to inspect the prognosis of OSCC patients.

RESULTS

Our results showed that OSCC cells treated with exosomes from GBP5-silenced OSCC cells reduced colony formation. Also, 56 differentially expressed exosomal miRNAs were found in GBP5-silenced OSCC cells compared to scrambled OSCC cells. Among them, exosomal miR-320d exhibited the highest negative correlation with GBP5 in OSCC patients. High GBP5/low miR-320d co-expression was linked to reduced disease-free survival (DFS) in patients with OSCC. Interestingly, the inhibitory effect of GBP5-silenced exosomes on OSCC cell growth was reversed by miR-320d inhibitors. Moreover, five miR-320d target genes were predicted, and only Family with Sequence Similarity 49, Member B (FAM49B) showed a negative correlation with miR-320d. A decreased level of FAM49B was found in OSCC cells treated with exosomes derived from GBP5-silenced OSCC cells, while the decreased level of FAM49B was reversed by miR-320d inhibitors. Silencing FAM49B and GBP5-silenced exosomes enhanced the cytotoxicity of paclitaxel. FAM49B was abundantly expressed in tumor tissues, and high FAM49B/low miR-320d and high GBP5/high FAM49B co-expression were linked to reduced DFS of OSCC patients.

CONCLUSION

Our study suggests that GBP5 downregulated exosomal miR-320d may trigger FAM49B expression and facilitate OSCC tumor growth and progression.

Pyroptosis for osteoarthritis treatment: insights into cellular and molecular interactions inflammatory

Osteoarthritis (OA) is a widely prevalent chronic degenerative disease often associated with significant pain and disability. It is characterized by the deterioration of cartilage and the extracellular matrix (ECM), synovial inflammation, and subchondral bone remodeling. Recent studies have highlighted pyroptosis-a form of programmed cell death triggered by the inflammasome-as a key factor in sustaining chronic inflammation. Central to this process are the inflammatory cytokines interleukin-1β (IL-1β) and interleukin-18 (IL-18), which play crucial roles mediating intra-articular pyroptosis through the NOD-like receptor protein 3 (NLRP3) inflammasome. This paper investigates the role of the pyroptosis pathway in perpetuating chronic inflammatory diseases and its linkage with OA. Furthermore, it explores the mechanisms of pyroptosis, mediated by nuclear factor κB (NF-κB), the purinergic receptor P2X ligand-gated ion channel 7 (P2X7R), adenosine monophosphate (AMP)-activated protein kinase (AMPK), and hypoxia-inducible factor-1α (HIF-1α). Additionally, it examines the interactions among various cellular components in the context of OA. These insights indicate that targeting the regulation of pyroptosis presents a promising therapeutic approach for the prevention and treatment of OA, offering valuable theoretical perspectives for its effective management.

MiR-103-3p regulates chondrocyte autophagy, apoptosis, and ECM degradation through the PI3K/Akt/mTOR pathway by targeting CPEB3

BACKGROUND

Chondrocyte apoptosis is associated with the severity of cartilage destruction and matrix degeneration in the progression of osteoarthritis. Increasing evidence indicates that autophagy has a significant cytoprotective effect against chondrocyte apoptosis. Here, we investigated the role of microRNA-103-3p (miR-103-3p) in regulating chondrocyte function and elucidated the underlying mechanism.

METHODS

MiR-103-3p expression in interleukin-1β (IL-1β)-stimulated chondrocytes was evaluated using RT-qPCR. The targets of miR-103-3p predicted by online databases were verified using biotin-based pulldown assay and luciferase reporter assay. IL-1β stimulated-chondrocytes were transfected with miR-103-3p inhibitor along with siRNA targeting cytoplasmic polyadenylation element-binding protein3 (siCPEB3), the autophagy inhibitor 3-MA, or the PI3K agonist 740 Y-P. Chondrocyte proliferation was evaluated using cell counting kit-8. Apoptosis was detected by flow cytometry. The levels of apoptosis-, extracellular matrix (ECM)-, autophagy-, and the PI3K/Akt/mTOR pathway-related proteins in chondrocytes were detected using immunoblotting or immunofluorescence.

RESULTS

We found that IL-1β stimulation upregulated miR-103-3p and downregulated CPEB3 in mouse chondrocytes. Inhibiting miR-103-3p reduced IL-1β-induced apoptosis and ECM macromolecule degradation while enhancing autophagy in chondrocytes. MiR-103-3p targeted CPEB3, and its downregulation rescued the expression of level in IL-1β stimulated-chondrocytes. MiR-103-3p downregulation inhibited the PI3K/Akt/mTOR pathway in IL-1β stimulated-chondrocytes by upregulating CPEB3. 3-MA, 740 Y-P, or CPEB3 knockdown counteracted the effect of miR-103-3p downregulation on chondrocyte apoptosis, ECM macromolecule degradation, and autophagy.

CONCLUSION

Overall, inhibition of miR-103-3p reduces IL-1β-induced apoptosis and ECM macromolecule degradation in chondrocytes by enhancing autophagy through the CPEB3/PI3K/Akt/mTOR pathway.

Extracellular vesicles of ADSCs inhibit ischemic stroke-induced pyroptosis through Gbp3 regulation: A role for the NLRP3/GSDMD signaling pathway

BACKGROUND

Mounting data indicates that extracellular vesicles (EVs) have the potential to improve the injury after a stroke. Pyroptosis is a recently identified kind of programmed cell death that initiates an inflammatory reaction. We aimed to ascertain the therapeutic implications and possible molecular processes of EVs obtained from adipose-derived stem cells (ADSCs) in inhibiting pyroptosis in ischemic stroke.

METHODS

The investigation employed transient middle cerebral artery occlusion (tMCAO) rat model and a BV2 of oxygen-glucose deprivation/reoxygenation (OGD/R) to ascertain ADSCs-EVs implications on inflammation and pyroptosis as assessed by neurological deficit scores, TTC staining, IHC, HE, CCK8, WB, ELISA, and immunofluorescence. RNA-Seq was performed on BV2 cells in the control, OGD/R, and OGD/R + ADSCs-EVs groups. Using sequencing data analysis, in the OGD/R group, we screened the upregulated genes regulated by EVs, overlapped with 74 pyroptosis-related genes, and identified Guanylate-binding protein 2 (Gbp2) and Guanylate-binding protein 3 (Gbp3) as key genes. Following the validation of the sequencing results in vivo and in vitro, Gbp3 was selected for further study. To test its regulatory effects on inflammation and pyroptosis, Gbp3 was knocked down and overexpressed in vitro.

RESULTS

The administration of ADSCs-EVs resulted in a significant reduction in neurological involvement scores and reduced infarct volume in rats with tMCAO. They were also protective against BV-2 cells after OGD/R. In vivo and in vitro, ADSCs-EVs inhibited inflammatory response and pyroptosis after stroke. The outcomes of the RNA-Seq data analysis manifested that the protective implications of EVs after stroke are mediated by the modulation of inflammation-related mechanisms. Moreover, treatment with EVs led to a significant reduction in Gbp3 expression in post-ischemic brain tissue and cells. When Gbp3 was knocked down, the expression of inflammatory molecules and proteins linked to pyroptosis had a significant decline. When Gbp3 was overexpressed, the opposite results were obtained.

CONCLUSIONS

ADSCs-EVs modulate the NLRP3/GSDMD signaling pathway via Gbp3 to attenuate the inflammatory response and reduce pyroptosis that occurs after stroke.

WTAP mediates IL-1β-induced chondrocyte injury by enhancing CA12 mRNA stability depending on m6A modification

BACKGROUND

Osteoarthritis (OA) poses a significant risk to the mobility of patients. Carbonic anhydrase 12 (CA12) can boost apoptosis and inflammation in several cancers, but its role in OA is unknown.

METHODS

Differentially expressed genes in OA were analyzed using the GEO database (GSE169077). RT-qPCR and western blot estimated relative mRNA and protein levels of CA12. Cell viability and apoptosis were estimated by cell counting and flow cytometry assays. Oxidative stress (OxS) was determined by detecting with ROS and MDA levels, as well as CAT and SOD activities. Cytokine levels of IL-6 and TNF-α were detected by ELISA. Parameters associated with apoptosis and extracellular matrix (ECM) were detected by western blot. The m6A modification profile was determined by methylated RNA immunoprecipitation assays.

RESULTS

Relative CA12 and wilms' tumor 1-associating protein (WTAP) mRNA and protein levels were overexpressed in OA articular cartilages and IL-1β-challenged chondrocytes CHON-001. CA12 silencing impaired IL-1β-induced cell apoptosis, inflammation, OxS, and ECM degradation in chondrocytes. Yet, CA12 overexpression exerted an opposing function. WTAP reinforced the stability of CA12 mRNA depending on the m6A modification. Furthermore, WTAP knockdown weakened cell apoptosis, inflammation, OxS, and ECM degradation in chondrocytes induced by IL-1β, but these changes were impaired after CA12 overexpression. In addition, WTAP knockdown mitigates cartilage degeneration in DMM-induced mouse models.

CONCLUSION

IL-1β-induced WTAP enhances CA12 mRNA stability depending on m6A modification, thus promoting chondrocyte apoptosis, inflammatory response, OxS, and ECM degradation, providing evidence to support the possibility of WTAP and CA12 as potential targets for OA treatment.

Vinpocetine protects against osteoarthritis by inhibiting ferroptosis and extracellular matrix degradation via activation of the Nrf2/GPX4 pathway

BACKGROUND

Osteoarthritis (OA) is a progressive joint condition marked by the slow degradation of articular cartilage. Vinpocetine (Vin), a synthetic derivative of vincamine derived from the vinca plant, exhibits anti-inflammatory and antioxidant properties. Nevertheless, the specific role and mechanism of Vin in the treatment of OA remain largely unexplored.

OBJECTIVES

The study is designed to uncover the impacts of Vin on tert‑butyl hydroperoxide (TBHP)-induced ferroptosis and to explore its potential role and underlying mechanisms in the treatment of OA. Concurrently, we established an OA mouse model through medial meniscal instability surgery to assess the therapeutic effects of Vin in vivo.

METHODS

Through network pharmacology analysis, we have identified the key targets and potential pathways of Vin. To simulate an oxidative stress-induced OA environment in vitro, we induced chondrocyte injury using TBHP. We tested how Vin affects chondrocytes under TBHP induction by DHE and DCFH-DA probes, BODIPY-C11 and FerroOrange staining, mitochondrial function assessment, Western blotting, co-immunoprecipitation, and immunofluorescence techniques. Simultaneously, we established an OA mouse model through medial meniscal instability surgery to assess the in vivo therapeutic effects of Vin. In this model, we used X-ray and micro-CT imaging, SO staining, TB staining, H&E staining, and immunohistochemistry to analyze the role of Vin in detail.

RESULTS

This study demonstrated that Vin effectively suppressed TBHP-induced ferroptosis and extracellular matrix (ECM) degradation and significantly lessened mitochondrial damage associated with ferroptosis. In the OA mouse model, Vin improved cartilage degeneration, subchondral remodeling, synovitis, and ECM degradation. Vin worked by activating the Nrf2/GPX4 pathway and inhibiting the Keap1-Nrf2 interaction. This study focused on the function of ferroptosis in OA and its influence on chondrocyte damage and disease progression, offering novel perspectives on potential treatments.

CONCLUSION

Vin activated the Nrf2/GPX4 pathway, thereby slowing OA progression, inhibiting ferroptosis, and preventing ECM degradation.

Therapeutic framework nucleic acid complexes targeting oxidative stress and pyroptosis for the treatment of osteoarthritis

Osteoarthritis (OA) is one of the most prevalent joint diseases and severely affects the quality of life in the elderly population. However, there are currently no effective prevention or treatment options for OA. Oxidative stress and pyroptosis play significant roles in the development and progression of OA. To address this issue, we have developed a novel therapeutic approach for OA that targets oxidative stress and pyroptosis. We synthesized tetrahedral framework nucleic acid (tFNAs) to form framework nucleic acid complexes (TNCs), which facilitate the delivery of the naturally occurring polymethoxyflavonoid nobiletin (Nob) to chondrocytes. TNC has demonstrated favorable bioavailability, stability, and biosafety for delivering Nob. Both in vitro and in vivo experiments have shown that TNC can alleviate OA and protect articular cartilage from damage by eliminating oxidative stress, inhibiting pyroptosis, and restoring the extracellular matrix anabolic metabolism of chondrocytes. These findings suggest that TNC has significant potential in the treatment of OA and cartilage injury.

Role of deubiquitinase USP47 in cardiac function alleviation and anti-inflammatory immunity after myocardial infarction by regulating NLRP3 inflammasome-mediated pyroptotic signal pathways

Myocardial infarction (MI) is an event of heart attack due to the formation of plaques in the interior walls of the arteries. This study is conducted to explore the role of ubiquitin-specific peptidase 47 (USP47) in cardiac function and inflammatory immunity. MI mouse models were established, followed by an appraisal of cardiac functions, infarct size, pathological changes, and USP47 and NLRP3 levels. MI cell models were established in HL-1 cells using anoxia. Levels of cardiac function-associated proteins, USP7, interferon regulatory factor 1 (IRF1), platelet factor-4 (CXCL4), pyroptotic factors, and neutrophil extracellular traps (NETs) were determined. The bindings of IRF1 to USP47 and the CXCL4 promoter and the ubiquitination of IRF1 were analyzed. USP47 was upregulated in myocardial tissues of MI mice. USP47 inhibition alleviated cardiac functions, and decreased infarct size, pro-inflammatory cytokines, NETs, NLRP3, and pyroptosis. The ubiquitination and expression levels of IRF1 were increased by silencing USP47, and IRF1 bound to the CXCL4 promoter to promote CXCL4. Overexpression of IRF1 or CXCL4 in vitro and injection of Nigericin in vivo reversed the effect of silencing USP47 on alleviating pyroptosis and cardiac functions. Collectively, USP47 stabilized IRF1 and promoted CXCL4, further promoting pyroptosis, impairing cardiac functions, and aggravating immune inflammation through NLRP3 pathways.

Pyroptosis-related crosstalk in osteoarthritis: Macrophages, fibroblast-like synoviocytes and chondrocytes

The pathogenesis of osteoarthritis (OA) involves a multifaceted interplay of inflammatory processes. The initiation of pyroptosis involves the secretion of pro-inflammatory cytokines and has been identified as a critical factor in regulating the development of OA. Upon initiation of pyroptosis, a multitude of inflammatory mediators are released and can be disseminated throughout the synovial fluid within the joint cavity, thereby facilitating intercellular communication across the entire joint. The main cellular components of joints include chondrocytes (CC), fibroblast-like synoviocytes (FLS) and macrophages (MC). Investigating their interplay can enhance our understanding of OA pathogenesis. Therefore, we comprehensively examine the mechanisms underlying pyroptosis and specifically investigate the intercellular interactions associated with pyroptosis among these three cell types, thereby elucidating their collective contribution to the progression of OA. We propose the concept of ' CC-FLS-MC pyroptosis-related crosstalk', describe the various pathways of pyroptotic interactions among these three cell types, and focus on recent advances in intervening pyroptosis in these three cell types for treating OA. We hope this will provide a possible direction for diversification of treatment for OA. The Translational potential of this article. The present study introduces the concept of 'MC-FLS-CC pyroptosis-related crosstalk' and provides an overview of the mechanisms underlying pyroptosis, as well as the pathways through which it affects MC, FLS, and CC. In addition, the role of regulation of these three types of cellular pyroptosis in OA has also been concerned. This review offers novel insights into the interplay between these cell types, with the aim of providing a promising avenue for diversified management of OA.

Characteristics of immune cells and causal relationship with chondromalacia: A two-sample, bidirectional mendelian randomization study

Chondromalacia, characterized by the softening of cartilage, is a prevalent condition affecting joint health with complex etiology. The immune system's role in its pathogenesis has been implicated but remains to be fully elucidated. To address a critical knowledge gap, we conducted a two-sample Mendelian randomization analysis of 731 immune cell phenotypes, assessing parameters like fluorescence, cell count, and morphology. After sensitivity and pleiotropy checks, and applying a false discovery rate correction, our study linked 17 phenotypes to chondromalacia (p < .05). Among them, seven immune cell phenotypes were found to have a protective effect against chondromalacia (IVW: p < .05, OR <1), while 10 were considered risk factors (IVW:p < .05, OR >1). Despite the constraints of sample size and possible genetic differences among populations, our research has identified a notable genetic correlation between specific immune cell indicators and chondromalacia. This breakthrough sheds light on the pathophysiological mechanisms of the condition. The identification of protective and risk-associated immune cell phenotypes provides a foundation for further exploration of immunological mechanisms in chondromalacia and may pave the way for targeted interventions. Future research is warranted to validate these findings and explore their clinical implications.