Laquinimod Mitigated IL-1β-Induced Impairment of the Cartilage Extracellular Matrix in Human ATDC5 Chondrocytes

A mini-invasive injectable hydrogel for temporomandibular joint osteoarthritis: Its pleiotropic effects and multiple pathways in cartilage regeneration

There are two bottlenecks in the treatment of TMJOA (temporomandibular joint osteoarthritis): ① lacking of easy-to-use repairing materials for damaged condylar cartilage; ② local inflammation interfering with in situ regeneration. In response to them, we constructed a biomimetic tilapia type I gelatin/hyaluronic acid (TGI/HA) hydrogel in this paper. It was endowed with the capability to immunoregulate mircoenvironment and concurrently induce regeneration in multiple ways. It not only reduced excretion of ECM-degrading enzymes and inflammatory factors, therefore reversing local inflammation, but also created microenvironment conducive to reparation by acting upon macrophages and T cells. In in vivo experiments, the TGI/HA hydrogel effectively restored the damaged cartilage on rat condyle, suggesting it had potential in clinical application.

Spermidine protects cartilage from IL-1β-mediated ferroptosis

Rheumatoid arthritis is characterized by a burst of inflammation, the destruction of cartilage and the abundant release of inflammatory factors such as IL-1β. Thus, the effect of IL-1β on cartilage was examined in this study. IL-1β could cause lipid peroxidation and disturbances in iron metabolism by increasing the expression of NCOA4 and decreasing the expression of FTH, which also induced ferritinophagy. In addition, the expression of the key antioxidant proteins SLC7A11 and GPX4 was inhibited by IL-1β, resulting in ferroptosis in chondrocytes. Spermidine (SPD), a low-molecular-weight aliphatic nitrogen-containing compound that widely exists in animals, has been reported to be an antioxidant. In our study, we found that SPD could inhibit ferritinophagy and reverse the decrease in the expression of SLC7A11 and GPX4. Therefore, we uncovered one of the molecular mechanisms of cartilage destruction and inflammation and provide a potential polyamine for the treatment of RA.

The role and intervention of mitochondrial metabolism in osteoarthritis

Osteoarthritis (OA), a prevalent degenerative joint disease, affects a substantial global population. Despite the elusive etiology of OA, recent investigations have implicated mitochondrial dysfunction as a significant factor in disease pathogenesis. Mitochondria, pivotal cellular organelles accountable for energy production, exert essential roles in cellular metabolism. Hence, mitochondrial dysfunction can exert broad-ranging effects on various cellular processes implicated in OA development. This comprehensive review aims to provide an overview of the metabolic alterations occurring in OA and elucidate the diverse mechanisms through which mitochondrial dysfunction can contribute to OA pathogenesis. These mechanisms encompass heightened oxidative stress and inflammation, perturbed chondrocyte metabolism, and compromised autophagy. Furthermore, this review will explore potential interventions targeting mitochondrial metabolism as means to impede or decelerate the progression of OA. In summary, this review offers a comprehensive understanding of the involvement of mitochondrial metabolism in OA and underscores prospective intervention strategies.

Laquinimod attenuates oxidative stress-induced mitochondrial injury and alleviates intervertebral disc degeneration by inhibiting the NF-κB signaling pathway

BACKGROUND

Low back pain (LBP) caused by intervertebral disc degeneration (IVDD) is a significant global health concern. It is necessary to investigate the underlying pathological mechanisms leading to IVDD and develop precise treatment strategies for this condition. Considering the well-established anti-inflammatory properties and ability to reduce oxidative stress in various diseases, for the first time we aim to explore the potential of Laquinimod in alleviating IVDD.

METHODS

We used hydrogen peroxide (H2O2) to simulate the oxidative stress microenvironment in IVDD, and Laquinimod for intervention purposes. Western blot analysis, quantitative real-time polymerase chain reaction (qRT-PCR), enzyme-linked immunosorbent assay (ELISA), and immunofluorescence assay were used to measure the expression levels of inflammatory cytokines, catabolic enzymes, and markers of extracellular matrix (ECM) synthesis in nucleus pulposus (NP) cells. In addition, dichlorofluorescin-diacetate (DCFH-DA) and JC-1 fluorescent probes, flow cytometry analysis, and qRT-PCR were used to measure mitochondrial function and apoptosis in NP cells under conditions of oxidative stress. An acupuncture-induced rat model of IVDD was established to further evaluate the efficacy of Laquinimod in alleviating IVDD in vivo.

RESULTS

Our findings showed that Laquinimod significantly reduced the oxidative stress-induced inflammatory response in NP cells, downregulated the expression of catabolic enzymes, and markedly enhanced ECM degradation by inhibiting the NF-κB signaling pathway. The administration of Laquinimod concurrently improved the mitochondrial functional state and reduced apoptosis in NP cells. Additionally, in vivo experiments in rats showed that Laquinimod significantly alleviated acupuncture-induced IVDD.

CONCLUSIONS

Collectively, the findings of this study provide new insights into the therapeutic potential of Laquinimod as a treatment for oxidative stress-induced IVDD.

Genkwanin suppresses mitochondrial dysfunction to alleviate IL-1β-elicited inflammation, apoptosis, and degradation of extracellular matrix in chondrocytes through upregulating DUSP1

Osteoarthritis (OA) is a form of chronic degenerative disease contributing to elevated disability rate among the elderly. Genkwanin is an active component extracted from Daphne genkwa possessing pharmacologic effects. Here, this study is designed to expound the specific role of genkwanin in OA and elaborate the probable downstream mechanism. First, the viability of chondrocytes in the presence or absence of interleukin-1 beta (IL-1β) treatment was detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay was used to assess cell apoptosis. Inflammatory response was estimated through enzyme-linked immunosorbent assay and Western blot. In addition, immunofluorescence staining and Western blot were utilized to measure the expression of extracellular matrix (ECM)-associated proteins. Dual-specificity protein phosphatase-1 (DUSP1) expression was tested by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and Western blot. Following DUSP1 elevation in genkwanin-treated chondrocytes exposed to IL-1β, inflammatory response and ECM-associated factors were evaluated as forementioned. In addition, 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolocarbocyanine iodide staining was to assess the mitochondrial membrane potential. Adenosine triphosphate (ATP) level was examined with ATP assay kit, and RT-qPCR was used to test mitochondrial DNA expression. Results indicated that genkwanin administration enhanced the viability while ameliorated the apoptosis, inflammatory response, and ECM degradation in IL-1β-induced chondrocytes. Besides, genkwanin treatment fortified DUSP1 expression in IL-1β-exposed chondrocytes. DUSP1 interference further offsets the impacts of genkwanin on the inflammation, ECM degradation, and mitochondrial dysfunction in IL-1β-challenged chondrocytes. In short, genkwanin enhanced DUSP1 expression to mitigate mitochondrial dysfunction, thus ameliorating IL-1β-elicited inflammation, apoptosis, and degradation of ECM in chondrocytes.

CKLF1 interference alleviates IL‑1β‑induced inflammation, apoptosis and degradation of the extracellular matrix in chondrocytes via CCR5

Osteoarthritis (OA) is a type of joint disease with a rising prevalence and incidence among the elderly across the global population. Chemokine-like factor 1 (CKLF1) is a human cytokine, which has been demonstrated to be involved in the progression of multiple human diseases. However, little attention has been paid to the impact of CKLF1 on OA. The present study was designed to identify the role of CKLF1 in OA and to clarify the regulatory mechanism. The expression levels of CKLF1 and its receptor CC chemokine receptor 5 (CCR5) were examined by reverse transcription-quantitative PCR (RT-qPCR) and western blotting. A Cell Counting Kit-8 assay was used to estimate cell viability. The levels and expression of inflammatory factors were determined by ELISA and RT-qPCR, respectively. Apoptosis was investigated by TUNEL assays and the protein levels of apoptosis-related factors were analyzed by western blotting. RT-qPCR and western blotting were used to examine the expression of extracellular matrix (ECM) degradation-associated proteins and ECM components. Dimethylmethylene blue analysis was used to analyze the production of soluble glycosamine sulfate additive. A co-immunoprecipitation assay was used to confirm the protein interaction between CKLF1 and CCR5. The results revealed that CKLF1 expression was increased in IL-1β-exposed murine chondrogenic ATDC5 cells. Furthermore, CKLF1 silencing enhanced the viability of IL-1β-induced ATDC5 cells, while inflammation, apoptosis and degradation of the ECM were reduced. Additionally, CKLF1 knockdown led to decreased CCR5 expression in IL-1β-challenged ATDC5 cells, and CKLF1 bound with CCR5. The enhanced viability, as well as the suppressed inflammation, apoptosis and degradation of the ECM, following CKLF1 knockdown in the IL-1β-induced ATDC5 cells were all restored after CCR5 was overexpressed. In conclusion, CKLF1 might serve a detrimental role in the development of OA by targeting its receptor CCR5.

Knockdown of lncRNA XIST Ameliorates IL-1β-Induced Apoptosis of HUVECs and Change of Tissue Factor Level via miR-103a-3p/HMGB1 Axis in Deep Venous Thrombosis by Regulating the ROS/NF-κB Signaling Pathway

Background

The effect of lncRNA X inactive-specific transcript (XIST) inducing cardiovascular diseases on deep vein thrombosis (DVT) and its mechanism has not been reported. In this study, we uncovered the mystery that lncRNA XIST causes DVT with HUVEC dysfunction.

Method

The expression levels of lncRNA XIST and miR-103a-3p were detected by qRT-PCR, and HMGB1 expression was determined by qRT-PCR and western blot. The correlations among the expression levels of lncRNA XIST, miR-103a-3p, and HMGB1 were determined by Spearman's rank-order correlation test. XIST siRNA (si-XIST) was transfected into HUVECs to knock down the intrinsic expression of lncRNA XIST. The influences of si-XIST on interleukin-1 beta- (IL-1β-) treated HUVEC viability and apoptosis and the level of tissue factor (TF) were detected by MTT, flow cytometry, and ELISA kit, respectively. The relationships between lncRNA XIST, miR-103a-3p, and HMGB1 were predicted by the Encyclopedia of RNA Interactomes (ENCORI) database and verified by dual luciferase reporter assay. The effects of lncRNA XIST and miR-103a-3p on HMGB1 expression were detected by qRT-PCR, western blot, and immunofluorescence analysis. The levels of ROS/NF-κB pathway-related proteins were detected to study the regulatory mechanism of lncRNA XIST/miR-103a-3p/HMGB1 on IL-1β-treated HUVECs apoptosis and change of TF level.

Results

The upregulated expression levels of lncRNA XIST and HMGB1 and downregulated level of miR-103a-3p were found in the plasma of DVT patients and IL-1β-treated HUVECs. Si-XIST promoted cell viability and inhibited HUVEC apoptosis and ameliorated the change of TF level triggered by IL-1β. lncRNA XIST sponged miR-103a-3p and miR-103a-3p targeted HMGB1. Si-XIST inhibited the ROS/NF-κB pathway to suppress HUVEC apoptosis and ameliorate the change of TF level induced by IL-1β via the miR-103a-3p/HMGB1 axis.

Conclusion

lncRNA XIST sponged miR-103a-3p improving HMGB1 expression to exacerbate DVT by activating the ROS/NF-κB signaling pathway. Our findings indicated that lncRNA XIST can be used as a potential therapeutic target in DVT.

The protective effects of Olmesartan against interleukin-29 (IL-29)-induced type 2 collagen degradation in human chondrocytes

Osteoarthritis (OA) is a cartilage degenerative disease commonly observed in the elderly population and is pathologically characterized by the degradation of the cartilage extracellular matrix (ECM). Matrix metalloproteinases (MMPs) and a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTSs) are critical enzymes involved in the degradation of ECM. Olmesartan is an inhibitor of the angiotensin II receptor developed for the treatment of hypertension, and recent studies show that it exerts anti-inflammatory effects in arthritis. The present study aimed to investigate the mechanism of the protective effect of Olmesartan on cartilage ECM degradation. Interleukin-29 (IL-29) is a novel inflammatory mediator involved in the inflammation and degradation of cartilage in OA, and human T/C-28a2 cells treated with it were the inflammatory model in vitro. We found that the degradation of type 2 collagens and aggrecans was induced by IL-29, accompanied by the upregulation of MMPs and ADAMTSs, but the presence of Olmesartan significantly ameliorated these increases. In addition, Olmesartan abolished IL-29- induced oxidative stress and elevated the expression level of TNF receptor-associated factor 6 (TRAF-6). Mechanistically, we showed that Olmesartan suppressed IL-29- caused inhibitor kappa B α (IκBα) expression and nuclear translocation of nuclear factor kappa-B (NF-κB) p65, indicating it suppressed the activation of the NF-κB pathway. Collectively, our data reveal that Olmesartan exerted a protective function on IL-29- induced type 2 collagen degradation in human chondrocytes.

Montelukast attenuates interleukin IL-1β-induced oxidative stress and apoptosis in chondrocytes by inhibiting CYSLTR1 (Cysteinyl Leukotriene Receptor 1) and activating KLF2 (Kruppel Like Factor 2)

Montelukast is a cysteinyl leukotriene receptor 1 (CysLTR1) antagonist widely used to suppress the inflammatory response in asthma and allergic rhinitis. This study aimed to investigate the potential impacts of montelukast on osteoarthritis (OA) progression. To determine the role of montelukast in OA, the expression of CysLTR1 was first examined by quantitative reverse transcription PCR (RT-qPCR) and western blot in IL-1β-induced ATDC5 cells treated with or without montelukast. Subsequently, the impacts of montelukast on cell viability and oxidative stress were measured by Cell-Counting-Kit-8 (CCK-8), commercial kits and western blot. Oxidative stress-related protein expressions were determined by western blot analysis in Il-1β-induced ATDC5 cells. Cell apoptosis and cartilage degradation were examined by TdT-mediated dUTP Nick-End Labeling (TUNEL) assay, western blot and RT-qPCR. KLF2 expression was measured in IL-1β-induced ATDC5 cells treated with montelukast. After interference with small interfering RNA (siRNA)-KLF2 in ATDC5 cells, the loss-of-function assays were also performed in same ways. CysLTR1 expression was elevated in IL-1β-induced ATDC5 cells but inhibited significantly by montelukast. Montelukast attenuated the oxidative stress and apoptosis, improved cell viability. Moreover, montelukast enhanced KLF2 expression. After transfected with siRNA-KLF2, montelukast attenuated cell injury, oxidative stress, apoptosis and cartilage degradation in IL-1β-induced ATDC5 cells by activating KLF2.In summary, this work elaborates the evidence that montelukast could attenuate oxidative stress and apoptosis in IL-1β-induced chondrocytes by inhibiting CysLTR1 and activating KLF2, which can guide the therapeutic strategies of montelukast for OA development in the future.

Laquinimod dampens IL-1β signaling and Th17-polarizing capacity of monocytes in patients with MS

OBJECTIVE

To assess the impact of laquinimod treatment on monocytes and to investigate the underlying immunomodulatory mechanisms in MS.

METHODS

In this cross-sectional study, we performed in vivo and in vitro analyses of cluster of differentiation (CD14⁺) monocytes isolated from healthy donors (n = 15), untreated (n = 13), and laquinimod-treated patients with MS (n = 14). Their frequency and the expression of surface activation markers were assessed by flow cytometry and the viability by calcein staining. Cytokine concentrations in the supernatants of lipopolysaccharide (LPS)-stimulated monocytes were determined by flow cytometry. The messenger ribonucleic acid (mRNA) expression level of genes involved in cytokine expression was measured by quantitative PCR. The LPS-mediated nuclear factor kappa-light-chain-enhancer of activated B-cell (NF-κB) activation was determined by the quantification of the phosphorylation level of the p65 subunit. Laquinimod-treated monocytes were cocultured with CD4⁺ T cells, and the resulting cytokine production was analyzed by flow cytometry after intracellular cytokine staining. The interleukin (IL)-17A concentration of the supernatant was assessed by ELISA.

RESULTS

Laquinimod did not alter the frequency or viability of circulating monocytes, but led to an upregulation of CD86 expression. LPS-stimulated monocytes of laquinimod-treated patients with MS secreted less IL-1β following a downregulation of IL-1β gene expression. Phosphorylation levels of the NF-κB p65 subunit were reduced after laquinimod treatment, indicating a laquinimod-associated inhibition of the NF-κB pathway. T cells primed with laquinimod-treated monocytes differentiated significantly less into IL-17A-producing T helper (Th)-17 cells.

CONCLUSIONS

Our findings suggest that inhibited NF-κB signaling and downregulation of IL-1β expression in monocytes contributes to the immunomodulatory effects of laquinimod and that the impairment of Th17 polarization might mediate its disease-modifying activity in MS.