TL1A/TNFR2-mediated mitochondrial dysfunction of fibroblast-like synoviocytes increases inflammatory response in patients with rheumatoid arthritis via reactive oxygen species generation

Exploring the impact of 2-hydroxyestradiol on heme oxygenase-1 to combat oxidative stress in rheumatoid arthritis

Rheumatoid arthritis (RA) is an autoimmune disease characterized by joint inflammation driven by complex signaling pathways. Recent therapeutic approaches focus on small molecules targeting intracellular signaling to address specific physiological aspects of the disease. Previously we identified a small molecule, 2-hydroxyestradiol (2-OHE2), an inhibitor of TNF-α by an in-silico study. In the present study, our aim was to explore the efficacy of 2-OHE2 by studying the proteome profile of rheumatoid arthritis fibroblast-like synoviocytes (RA-FLS) using SWATH-MS and validate its therapeutic potential in RA by in-vitro studies. Oxidative stress was assessed using various biochemical assays, and cellular bioenergetics were analyzed with the Seahorse XFe96 Analyzer. We identified 396 differential proteins by SWATH-MS, and 82 showed significant changes. PharmMapper analysis revealed the association of 2-OHE2 with HMOX1 (HO-1), confirmed by SWATH-MS data. Also, we revealed that 2-OHE2 enhanced the expression of HO-1 and lowered oxidative stress via activating the Nrf2/KEAP1/HO-1 pathway. Further, 2-OHE2 has been found to boost cellular respiration and ATP production. Our findings thus suggest that 2-OHE2 possesses therapeutic potential as an antioxidant for RA treatment, effective at low dosages.

Towards understanding the role of nanomedicine in targeting TNFR2 in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by inflammation of the synovium and progressive joint destruction which significantly affects both quality of life and socioeconomic status. Admittedly, various treatments are available, but they are usually accompanied by various side effects, from mild to severe, and potentially with adverse events. Tumour necrosis factor-alpha (TNF-α) plays a crucial role in the pathophysiology of RA. It promotes inflammatory, apoptosis and necroptosis via TNF receptor-1 (TNFR1) but elicit anti-inflammatory effects via TNFR2. Herein, targeting TNFR2 has gained attention in RA studies. Understanding the role of nanomedicine in modulating TNFR2 signalling may be the instrument in development of RA therapies. Nanotechnology has made a significant progress in treating various conditions of diseases since its inception. Due to this, nanomedicine has emerged as a promising therapeutics approach for RA. Recent studies have demonstrated the potential of nanomedicine in RA theranostics, combining therapy and diagnostics for improved treatment outcomes. Owing to the challenges and advancements in the field of nanotechnology, nanoparticles are seen as an applicable candidate in the treatment of RA. In this review, we provide an overview of the role of nanomedicine in targeting TNFR2 for the treatment of RA and highlight the limitations of current therapies as well as the potential of nanocarriers with controlled drug release and active targeting abilities.

Exploring the Mechanism of Acupuncture's Influence on the Protease Activity and Free Radical Damage in Synovial Fluid of Rheumatoid Arthritis Rats Induced by Type II Collagen from the Release of Active Oxygen

Acupuncture was studied to investigate the mechanism of its effect on protease vitality and free radical damage in Type I CIA rats induced by type II collagen. The study divided rats into a control group (injected with physiological saline, n = 10), a model group (injected with type II collagen, n = 10), and an intervention group (injected with type II collagen + acupuncture ST36 and GB39, 3 times a week, for a total of 4 weeks, n = 10) based on the different injected drugs. Then, various indicators of the mice were experimentally tested using joint index scoring, H&E histological staining, protein blotting, and immunohistochemistry staining methods. Acupuncture ST36 and GB39 can reduce arthritis scores, histological staining scores, and increase MVD in CIA rats. And reduce protease levels, alleviate inflammation, synovial hyperplasia, and angiogenesis. In addition, the intervention group TNF-α, IL-1β and IL-6 mRNA were reduced, and the clearance rates of hydrogen peroxide free radicals and nitric oxide free radicals were increased. The expression levels of ROS and MDA decrease, while the expression levels of SOD increase It has been proved that acupuncture at ST36 and GB39 can inhibit the release of ROS, reduce protease activity, inflammation, synovial hyperplasia, angiogenesis and free radical damage, thus reducing the severity of CIA (Collagen-Induced Arthritis) in rats.

Definition of Synovial Mesenchymal Stem Cells for Meniscus Regeneration by the Mechanism of Action and General Amp1200 Gene Expression

The quality control (QC) of pharmaceutical-grade cell-therapy products, such as mesenchymal stem cells (MSCs), is challenging. Attempts to develop such products have been hampered by difficulties defining cell-type-specific characteristics and therapeutic mechanisms of action (MoAs). Although we have developed a cell therapy product, FF-31501, consisting of human synovial MSCs (SyMSCs), it was difficult to find specific markers for SyMSCs and to define the cells separately from other MSCs. The purpose of this study was to create a method for identifying and defining SyMSCs from other tissue-derived MSCs and to delve deeper into the mechanism of action of SyMSC-induced meniscus regeneration. Specifically, as a cell-type-dependent approach, we constructed a set of 1143 genes (Amp1200) reported to be associated with MSCs and established a method to evaluate them by correlating gene expression patterns. As a result, it was possible to define SyMSCs separately from other tissue-derived MSCs and non-MSCs. In addition, the gene expression analysis also highlighted TNSF-15. The in vivo rat model of meniscus injury found TNSF-15 to be an essential molecule for meniscus regeneration via SyMSC administration. This molecule and previously reported MoA molecules allowed an MoA-dependent approach to define the mechanism of action for SyMSCs. Therefore, SyMSCs for meniscus regeneration were defined by means of two approaches: the method to separate them from other MSCs and the identification of the MoA molecules. These approaches would be useful for the QC of cell therapy products.

Tumor Necrosis Factor Receptor-2 Signals Clear-Cell Renal Carcinoma Proliferation via Phosphorylated 4E Binding Protein-1 and Mitochondrial Gene Translation

Clear-cell renal cell carcinoma (ccRCC), a tubular epithelial malignancy, secretes tumor necrosis factor (TNF), which signals ccRCC cells in an autocrine manner via two cell surface receptors, TNFR1 and TNFR2, to activate shared and distinct signaling pathways. Selective ligation of TNFR2 drives cell cycle entry of malignant cells via a signaling pathway involving epithelial tyrosine kinase, vascular endothelial cell growth factor receptor type 2, phosphatidylinositol-3-kinase, Akt, pSer727-Stat3, and mammalian target of rapamycin. In this study, phosphorylated 4E binding protein-1 (4EBP1) serine 65 (pSer65-4EBP1) was identified as a downstream target of this TNFR2 signaling pathway. pSer65-4EBP1 expression was significantly elevated relative to total 4EBP1 in ccRCC tissue compared with that in normal kidneys, with signal intensity increasing with malignant grade. Selective ligation of TNFR2 with the TNFR2-specific mutein increased pSer65-4EBP1 expression in organ cultures that co-localized with internalized TNFR2 in mitochondria and increased expression of mitochondrially encoded COX (cytochrome c oxidase subunit) Cox1, as well as nuclear-encoded Cox4/5b subunits. Pharmacologic inhibition of mammalian target of rapamycin reduced both TNFR2-specific mutein-mediated phosphorylation of 4EBP1 and cell cycle activation in tumor cells while increasing cell death. These results signify the importance of pSer65-4EBP1 in mediating TNFR2-driven cell-cycle entry in tumor cells in ccRCC and implicate a novel relationship between the TNFR2/pSer65-4EBP1/COX axis and mitochondrial function.

Mitochondrial functioning in Rheumatoid arthritis modulated by estrogen: Evidence-based insight into the sex-based influence on mitochondria and disease

Alteration of immune response and synovium microvasculature in Rheumatoid arthritis (RA) progression has been suggested to be associated with mitochondrial functioning. Mitochondria, with maternally inherited DNA, exhibit differential response to the female hormone estrogen. Various epidemiological evidence has also shown the prominence of RA in the female population, depicting the role of estrogen in modulating the pathogenesis of RA. As estrogen regulates the expression of differential proteins and associated signaling pathways of RA, its influence on mitochondrial functioning seems evident. Thus, in this review, the studies related to mitochondria and their relation with estrogen and Rheumatoid arthritis were retrieved. We analyzed the different mitochondrial activities that are altered in RA and the possibility of their estrogenic control. The study expands to in silico analysis, revealing the differential mitochondrial proteins expressed in RA and examining these proteins as potential estrogenic targets. It was found that ALDH2, CASP3, and SOD2 are the major mitochondrial proteins involved in RA progression and are also potent estradiol targets. The analysis establishes the role of mitochondrial proteins in RA progression, which were found to be direct or indirect targets of estrogen, depicting its potential for regulating mitochondrial functions in RA.

Unveiling the Nexus: Cellular Metabolomics Unravels the Impact of Estrogen on Nicotinamide Metabolism in Mitigating Rheumatoid Arthritis Pathogenesis

Rheumatoid arthritis (RA) is a metabolic joint disorder influenced by hormonal regulation, notably estrogen, which plays a cytoprotective role against inflammation. While estrogen's impact on RA pathogenesis has been studied, the altered metabolite expression under estrogen's influence remains unexplored. This study investigated the changes in the metabolome of synovial fibroblasts isolated from RA patients under 17β-estradiol (E2) using the liquid chromatography with tandem mass spectrometry (LC-MS/MS) approach followed by multivariate and biological pathway analysis along with in vitro validation. Results identified 3624 m/z, among which eight metabolites were significant (p < 0.05). Nicotinate and nicotinamide metabolism was found to be highly correlated with the treatment of E2, with metabolites NAD+ and 1-methynicotinamide (1-MNA) upregulated by E2 induction in RA-FLS. PharmMapper analysis identified potential gene targets of 1-MNA, which were further matched with RA gene targets, and thus, STAT1, MAPK14, MMP3, and MMP9 were concluded to be the common targets. E2 treatment affected the expression of these gene targets and ameliorated the development of oxidative stress associated with RA inflammation, which can be attributed to increased concentration of 1-MNA. Thus, an LC-MS/MS-based metabolomics study revealed the prominent role of estrogen in preventing inflammatory progression in RA by altering metabolite concentration, which can support its therapeutic capacity in remitting RA.

Irisin mitigates rheumatoid arthritis by suppressing mitochondrial fission via inhibiting YAP-Drp1 signaling pathway

BACKGROUND

Irisin is a hormone-like factor secreted by muscle cells and produced by cleavage of the membrane protein fibronectin type III domain protein 5 (FNDC5), which exerts anti-inflammatory and anti-proliferative effects. However, the effects and the underlying mechanisms of irisin in rheumatoid arthritis (RA) are still unclear.

METHOD

Collagen-induced arthritis (CIA) model was induced in DBA/1 mice and then treated with irisin. Arthritis index, paw thickness, weight, number of affected paws, serum inflammatory factors and related pathological tests were measured. RA fibroblast-like synoviocytes (RA-FLSs) were pretreated with IL-1β and irisin, and the migration, proliferation, invasion, oxidative stress and mitochondrial related function of RA-FLSs were detected.

RESULTS

Irisin significantly improved arthritis symptoms in CIA mice, as indicated by reduced arthritis index, alleviated paw thickness, decreased the number of affected paws and inhibited release of inflammatory factors. Irisin alleviated joint destruction, FLSs proliferation and the expression of YES-associated protein (YAP) and mitochondrial dynamic related protein 1 (Drp1) in the FLSs of CIA mice. In vitro experiment, irisin inhibited the proliferation, migration and invasion of RA-FLSs and improved oxidative stress induced by IL-1β, thereby restraining the pathogenic transformation of RA-FLSs. Mechanically, irisin suppressed the nuclear translocation of YAP, in turn, could reduce the synthesis of Drp1 protein and inhibit the mitochondrial fission of RA-FLSs, which was reversed by YAP agonists. Therefore, irisin has a protective effect on RA.

CONCLUSION

Irisin inhibits the proliferation, migration, invasion and inflammatory response of RA-FLSs by inhibiting the YAP-Drp1 signaling pathway, which implies a potential therapeutic effect on RA.

Role of mitochondrial dysfunction in the pathogenesis of rheumatoid arthritis: Looking closely at fibroblast- like synoviocytes

Rheumatoid arthritis (RA) is a chronic, autoimmune, and inflammatory disease that primarily targets the joints, leading to cartilage and bone destruction.Fibroblast-like synoviocytes (FLS) are specialized cells of the synovial lining in the joint that plays a fundamental role in the development of RA. Particularly, FLS of RA patients (RA-FLS) in the joint exhibit specific characteristics like higher invading and immunogenic properties, hyperproliferation, and reduced apoptotic capacity, suggesting a dysfunctional mitochondrial pool in these cells. Mitochondria are emerging as a potential organelle that can decide cellular immunometabolism, invasion properties, and cell death. Accordingly, multiplestudies established that mitochondria are crucial in establishing RA. However, the underlying mechanism of impaired mitochondrial function in RA remains poorly understood. This review will provide an overview of the mitochondrial role in the progression of RA, specifically in the context of FLS biology. We will also outline how mitochondria-centric therapeutics can be achieved that would yield novel avenues of research in pathological mediation and prevention.

Mitochondrial Dysfunction in the Pathogenesis and Treatment of Oral Inflammatory Diseases

Oral inflammatory diseases (OIDs) include many common diseases such as periodontitis and pulpitis. The causes of OIDs consist microorganism, trauma, occlusal factors, autoimmune dis-eases and radiation therapy. When treated unproperly, such diseases not only affect oral health but also pose threat to people's overall health condition. Therefore, identifying OIDs at an early stage and exploring new therapeutic strategies are important tasks for oral-related research. Mitochondria are crucial organelles for many cellular activities and disruptions of mitochondrial function not only affect cellular metabolism but also indirectly influence people's health and life span. Mitochondrial dysfunction has been implicated in many common polygenic diseases, including cardiovascular and neurodegenerative diseases. Recently, increasing evidence suggests that mitochondrial dysfunction plays a critical role in the development and progression of OIDs and its associated systemic diseases. In this review, we elucidated the critical insights into mitochondrial dysfunction and its involvement in the inflammatory responses in OIDs. We also summarized recent research progresses on the treatment of OIDs targeting mitochondrial dysfunction and discussed the underlying mechanisms.

SMSCs-derived sEV overexpressing miR-433-3p inhibits angiogenesis induced by sEV released from synoviocytes under triggering of ferroptosis

BACKGROUND

Ferroptosis is characterized by accumulation of lipid peroxides that leads to oxidative stress. In progressive rheumatoid arthritis (RA), fibroblast-like synoviocytes (FLS) suffered from oxidative stress induced by generation of excess reactive oxygen species (ROS) and survived from elevated lipid oxidation. However the phenomenon of abnormal synovial fibroblasts proliferation under ferroptotic stress remain to be explained and the effects of this event on disease progression of RA need to be investigated.

METHODS

FLS from RA patients (RA-FLS) were stimulated with LPS as an inflammatory model in vitro, and simultaneously treated with ferroptosis inducer Erastin/RSL3 or inhibitor ferrostatin-1. Besides, small extracellular vesicles (sEV) from the supernatant of RA-FLS culture under Erastin/RSL3 management were isolated. The degree of ferroptosis in cells were evaluated by Lipid-ROS detection via flowcytometry and ferroptosis marker protein expression determined by western bloting. The expression of core component of ESCRT-III CHMP4A and CHMP5 was determined by western bloting, and knockdown of CHMP4A was further performed to detect the influence of ESCRT-III complex on ferroptosis as well as LPS/Erastin induced sEV (LPS/Erastin-sEV) releasing. Moreover, miR-433-3p level in the isolated sEV was evaluated by RT-qPCR and interaction of miR-433-3p with FOXO1/VEGF axis were evaluated. MiR-433-3p was overexpressed in synovial mesenchymal stem cells (SMSCs) via miR-433-3p mimics transfection. RA-FLS was co-cultured with human dermal microvascular endothelial cells (HDMECs). LPS/Erastin-sEV or sEV derived from miR-433-3p-overexpressing SMSCs (miR-433-3p-SMSCs-sEV) were added to the co-culture system, and supernatants from co-culture without sEV were given to HDMECs. Angiogenic activity of HDMECs were identified by transwell test and endothelial tube formation analysis. Erastin-sEV and miR-433-3p-SMSCs-sEV were also administrated in collagen-induced arthritis (CIA) mouse model respectively, and progression of arthritis were evaluated.

RESULTS

Ferroptosis of RA-FLS was triggered by LPS/Erastin and accompanied with increased expression of ESCRT-III core components as well as elevated release of sEV from RA-FLS. HDMECs' migration and tube formation in vitro was significantly induced/suppressed by supernatants from co-culture under management of Erastin-sEV/miR-433-3p-SMSCs-sEV due to varied VEGF expression regulated by miR-433-3p targeting FOXO1. MiR-433-3p-SMSCs-sEV could inhibit the Erastin-sEV promoted VEGF expression and mitigated arthritis severity.

CONCLUSION

Erastin-sEV could aggravate synovial angiogenesis and promote arthritis progression. Administration of miR-433-3p-SMSCs-sEV may be a potential novel therapeutic method as significant antagonism to Erastin-sEV for RA treatment.

Aging of mesenchymal stem cell: machinery, markers, and strategies of fighting

Human mesenchymal stem cells (MSCs) are primary multipotent cells capable of differentiating into osteocytes, chondrocytes, and adipocytes when stimulated under appropriate conditions. The role of MSCs in tissue homeostasis, aging-related diseases, and cellular therapy is clinically suggested. As aging is a universal problem that has large socioeconomic effects, an improved understanding of the concepts of aging can direct public policies that reduce its adverse impacts on the healthcare system and humanity. Several studies of aging have been carried out over several years to understand the phenomenon and different factors affecting human aging. A reduced ability of adult stem cell populations to reproduce and regenerate is one of the main  contributors to the human aging process. In this context, MSCs senescence is a major challenge in front of cellular therapy advancement. Many factors, ranging from genetic and metabolic pathways to extrinsic factors through various cellular signaling pathways, are involved in regulating the mechanism of MSC senescence. To better understand and reverse cellular senescence, this review highlights the underlying mechanisms and signs of MSC cellular senescence, and discusses the strategies to combat aging and cellular senescence.

Mitochondria transfer restores fibroblasts-like synoviocytes (FLS) plasticity in LPS-induced, in vitro synovitis model

Background

Synovitis (SI) is one of the most common and serious orthopedic diseases in horses of different age, breed and sex, which contributes to the development of osteoarthritis. The burden of SI includes economic loss and represents a real challenge for current veterinary health care. At the molecular level, fibroblasts-like synoviocytes (FLS) are recognized as major cell populations involved in SI pathogenesis. In the course of SI, FLSs are losing their protective and pro-regenerative cytological features, become highly proliferative and initiate various stress signaling pathways.

Methods

Fibroblast-like synoviocytes were treated with LPS in order to generate SI in vitro model. Mitochondria were isolated from peripheral blood derived mononuclear cells and co-cultured with FLS. After 24 h of culture, cells were subjected to RT-qPCR, western blot, cytometric and confocal microscopy analysis.

Results

Mitochondrial transfer (MT) was observed in vitro studies using confocal microscopy. Further studies revealed, that MT to LPS-treated FLS reduced cell proliferation, modulated apoptosis and decreased inflammatory response. Overall, MT Resulted in the considerable recovery of recipient cells cytophysiological properties.

Conclusions

Presented data provides evidence that mitochondria transfersignificantly modulate FLS proliferative and metabolic activity through improved mitochondrial biogenesis and dynamics in activated FLS. Obtained results for the first time demonstrate that horizontal MT might be considered as a therapeutic tool for synovitis treatment; however, further clinical studies are strongly required.

Mitochondrial Dysfunction in Rheumatoid Arthritis

Rheumatoid arthritis, a chronic autoimmune disease with complex etiology, is characterized by excessive proliferation of synovial cells, massive production of inflammatory cells and cartilage destruction. Studies have shown that mitochondrial dysfunction plays an important role in promoting the occurrence of RA. Mitochondria with normal structure and function are essential for the normal survival of chondrocytes and synovial cells. Once mitochondrial function is destroyed, it will affect the survival, activation and differentiation of immune cells and non-immune cells involved in the pathogenesis of RA, thus leading to the occurrence of RA. However, the mechanism of mitochondrial dysfunction in RA remains unclear. This article reviews the method of mitochondrial dysfunction leading to RA, the effects of mitochondrial dysfunction on immune cells, the etiology of mitochondrial dysfunction in RA, and the pathology of mitochondrial dysfunction in RA. We also outline some drugs that can exert therapeutic effects on RA which are associated with modulating mitochondrial activity. The understanding and summary of mitochondrial dysfunction in RA may provide new research directions for pathological intervention and prevention of RA.

Role of TL1A in Inflammatory Autoimmune Diseases: A Comprehensive Review

TL1A, also called TNFSF15, is a member of tumor necrosis factor family. It is expressed in different immune cell, such as monocyte, macrophage, dendritic cell, T cell and non-immune cell, for example, synovial fibroblast, endothelial cell. TL1A competitively binds to death receptor 3 or decoy receptor 3, providing stimulatory signal for downstream signaling pathways, and then regulates proliferation, activation, apoptosis of and cytokine, chemokine production in effector cells. Recent findings showed that TL1A was abnormally expressed in autoimmune diseases, including rheumatoid arthritis, inflammatory bowel disease, psoriasis, primary biliary cirrhosis, systemic lupus erythematosus and ankylosing spondylitis. In vivo and in vitro studies further demonstrated that TL1A was involved in development and pathogenesis of these diseases. In this study, we comprehensively discussed the complex immunological function of TL1A and focused on recent findings of the pleiotropic activity conducted by TL1A in inflammatory autoimmune disease. Finish of the study will provide new ideas for developing therapeutic strategies for these diseases by targeting TL1A.

The enhanced mitochondrial dysfunction by cantleyoside confines inflammatory response and promotes apoptosis of human HFLS-RA cell line via AMPK/Sirt 1/NF-κB pathway activation

OBJECTIVE

Cantleyoside (CA) is a kind of iridoid glycosides in Pterocephalus hookeri (C. B. Clarke) Höeck. The purpose of this study was to investigate the effects of CA on human rheumatoid arthritis fibroblast synovial cells (HFLS-RA).

METHODS

Cell proliferation of HFLS-RA was assessed by CCK-8. ELISA was used to detect cytokines NO, TNF-α, IL-1β/6, MCP-1, MMP-1/3/9 and metabolism-related ATPase activities and ATP levels. JC-1, DCFH-DA, Fluo-3 AM and Calcein AM probes were used to detect mitochondrial membrane potential (MMP), reactive oxygen species (ROS), Ca²⁺ and mitochondrial permeability conversion pore (MPTP), respectively. Isolated mitochondria assay was used to detect mitochondrial swelling. Oxygen consumption rate (OCR), extracellular acidification rate (ECAR) and real-time ATP production were measured using a Seahorse analyzer. Apoptosis was detected by TUNEL and Hoechst staining. Western blot was used to detect the expressions of AMPK/p-AMPK, Sirt 1, IκBα, NF-κB p65/p-NF-κB p65, Bcl-2 and Bax. Cytoplasmic nuclear isolation was also performed to detect the translocation of NF-κB.

RESULTS

CA significantly suppressed cell proliferation and the levels of NO, TNF-α, IL-1β/6, MCP-1 and MMP-1/3/9 in HFLS-RA. In addition, CA promoted the apoptosis of HFLS-RA by increasing TUNEL and Hoechst positive cells and the ratio of Bax/Bcl-2. Inhibition of energy metabolism in HFLS-RA by CA reduced OCR, ECAR and real-time ATP generation rate. Importantly, CA promoted p-AMPK and Sirt 1 expression, inhibited IκBα degradation to reduce p-NF-κB and translocation.

CONCLUSION

The results suggest that CA activates the AMPK/Sirt 1/NF-κB pathway by promoting mitochondrial dysfunction, thereby exerting anti-inflammatory and pro-apoptotic effects.

Quercetin-mediated SIRT1 activation attenuates collagen-induced mice arthritis

ETHNOPHARMACOLOGICAL RELEVANCE

Herba taxilli (HT, Sangjisheng in Chinese), which is composed of the dried stems and leaves of Taxillus chinensis (DC.) Danser, has been commonly used to treat inflammation and arthritis in traditional Chinese medicine (TCM). Quercetin (Que) is a major active flavonoid component isolated from HT and is one of the quality control indexes of HT. In the clinical practice of TCM, formulas containing HT are commonly used to treat rheumatoid arthritis (RA). Recent studies have shown that Que exerts antiarthritic effects. However, the mechanism by which Que treatment affects RA is not fully understood.

AIM OF THE STUDY

This study aimed to explore the antiarthritic activity of Que in a collagen-induced arthritis (CIA) mouse model and investigate the underlying mechanisms.

MATERIALS AND METHODS

The antiarthritic activity of Que was evaluated in a CIA mouse model by determining the paw clinical arthritis scores and left ankle thicknesses and by conducting micro-PET imaging and histopathological analysis of ankle joint tissues. The proinflammatory cytokine (IL-6, TNF-α, IL-1β, IL-8, IL-13, IL-17) levels in the serum and ankle joint tissues were measured by ELISA. Mitochondrial oxidative stress was assessed by biochemical methods. Mitochondrial biogenesis was analysed by RT-qPCR. The protein levels of silent information regulator 1 (SIRT1), peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α), nuclear respiratory factor 1 (NRF1), mitochondrial transcription factor A (TFAM), high-mobility group box 1 (HMGB1), Toll-like receptor 4 (TLR4), p38, phospho-p38, extracellular signal-regulated kinases (ERK)-1/2, phospho-ERK1/2, p65, and phospho-p65 in ankle joint tissues were detected by Western blot analysis. A total of 30 RA patients were recruited to investigate the relationship between the disease activity score (DAS28) and the SIRT1, PGC-1α, NRF1, and HMGB1 plasma levels.

RESULTS

Que treatment decreased the clinical score and left ankle thickness of CIA mice, attenuated the synovial inflammation and hyperplasia and bone/cartilage destruction in ankle joints, and decreased the secretion of IL-6, TNF-α, IL-1β, IL-8, IL-13, and IL-17. Mechanistically, Que treatment improved impaired mitochondrial biogenesis and mitochondrial function by regulating the SIRT1/PGC-1α/NRF1/TFAM pathway and inhibited inflammation via the HMGB1/TLR4/p38/ERK1/2/NF-κB p65 pathway. Notably, epidemiological data revealed correlations between abnormal circulating levels of SIRT1, PGC-1α, NRF1, HMGB1 and RA disease activity in patients.

CONCLUSIONS

Our data suggested a potential role of Que as a dietary therapeutic drug for RA treatment that may act through SIRT1 to target mitochondrial biogenesis. Additionally, the role of impaired mitochondrial biogenesis in RA was evaluated.

Therapeutic effect of neohesperidin on TNF-α-stimulated human rheumatoid arthritis fibroblast-like synoviocytes

During the pathogensis of rheumatoid arthritis (RA), activated RA fibroblast-like synoviocytes (RA-FLSs) combines similar proliferative features as tumor and inflammatory features as osteoarthritis, which eventually leads to joint erosion. Therefore, it is imperative to research and develop new compounds, which can effectively inhibit abnormal activation of RA-FLSs and retard RA progression. Neohesperidin (Neo) is a major active component of flavonoid compounds with anti-inflammation and anti-oxidant properties. In this study, the anti-inflammation, anti-migration, anti-invasion, anti-oxidant and apoptosis-induced effects of Neo on RA-FLSs were explored to investigate the underlying mechanism. The results suggested that Neo decreased the levels of interleukin IL-1β, IL-6, IL-8, TNF-α, MMP-3, MMP-9 and MMP-13 in FLSs. Moreover, Neo blocked the activation of the MAPK signaling pathway. Furthermore, treatment with Neo induced the apoptosis of FLSs, and inhibited the migration of FLSs. It was also found that Neo reduced the accumulation of reactive oxygen species (ROS) induced by TNF-α. Taken together, our results highlighted that Neo may act as a potential and promising therapeutic drug for the management of RA.

TLRs Play Crucial Roles in Regulating RA Synoviocyte

Rheumatoid arthritis (RA) is an autoimmune inflammatory disease comparing the inflammation of synovium. Macrophage-like synoviocytes and fibroblast-like synoviocytes (synoviocytes) are crucial ingredients of synovium. Therein, a lot of research has focused on synoviocytes. Researches demonstrated that TLR1, TLR2, TLR3, TLR4, TLR5, TLR6 TLR7 and TLR9 are expressed in synoviocyte. Additionally, the expression of TLR2, TLR3, TLR4 and TLR5 is increased in RA synoviocyte. In this paper, we review the exact role of TLR2, TLR3, TLR4 and TLR5 participate in regulating the production of inflammatory factors in RA synoviocyte. Furthermore, we discuss the role of vasoactive intestinal peptide (VIP), MicroRNA, Monome of Chinese herb and other cells (Monocyte and T cell) influence the function of synoviocyte by regulating TLRs. The activation of toll-like receptors (TLRs) in synoviocyte leads to the aggravation of arthritis, comparing with angiogenesis and bone destruction. Above all, TLRs are promising targets for managing RA.

The relationship between TNF-like protein 1A and coronary artery aneurysms in children with Kawasaki disease

Kawasaki disease (KD) is an acute, systemic vasculitis of unknown etiology that occurs predominantly in infants and children, and the most crucial complication of KD is coronary artery aneurysm (CAA). Tumor necrosis factor (TNF)-like protein 1A (TL1A) is a member of the TNF superfamily, which possesses the ability of maintaining vascular homeostasis and regulating immune responses. This study aimed to examine serum TL1A levels in KD patients, and to investigate the relationship between TL1A and CAAs in children with KD. Blood samples were recruited from 119 KD patients, 35 febrile controls (FCs), and 37 healthy controls (HCs). The KD group was further divided into KD with CAAs (KD-CAAs) and KD non-CAAs (KD-NCAAs) groups. Serum TL1A levels were measured using enzyme-linked immunosorbent assays, and clinical parameters were collected from KD patients. Serum TL1A levels of KD patients in the acute phase of KD were significantly higher than in the FC and HC groups. In particular, serum TL1A levels were substantially increased in the KD-CAA group compared with the KD-NCAA group. Furthermore, TL1A levels in the KD group were positively correlated with the duration of fever and the time point of IVIG and WBC levels, but negatively correlated with levels of RBC, Hb and albumin. TL1A might be involved in KD-associated vasculitis and in the development of CAAs.

Downregulated MicroRNA-327 Attenuates Oxidative Stress-Mediated Myocardial Ischemia Reperfusion Injury Through Regulating the FGF10/Akt/Nrf2 Signaling Pathway

Although miR-327 had a protective effect on cardiomyocytes as described previously, the potential mechanism still needs further exploration. The aim of this study was to investigate the role and mechanism of miR-327 on oxidative stress in myocardial ischemia/reperfusion injury (MI/RI) process. Oxidative stress and cardiomyocytes injury were detected in rat model of MI/RI, hypoxia/reoxygenation (H/R), and tert-butyl hydroperoxide (TBHP) model of H9c2 cells. In vitro, downregulation of miR-327 inhibited both H/R- and TBHP-induced oxidative stress, and suppressed apoptosis. Meanwhile, fibroblast growth factor 10(FGF10) was enhanced by miR-327 knocked down, followed by the activation of p-PI3K and p-Akt, and the translocation of Nrf2. However, miR-327 overexpression performed with opposite effects. Consistent with the results in vitro, downregulation of miR-327 attenuated reactive oxygen species (ROS) generation as well as intrinsic apoptosis, and alleviated I/R injury. In conclusion, inhibition of miR-327 improved antioxidative ability and myocardial cell survival via regulating the FGF10/Akt/Nrf2 pathway.

Decoy Technology as a Promising Therapeutic Tool for Atherosclerosis

Cardiovascular diseases (CVDs) have been classified into several types of disease, of which atherosclerosis is the most prevalent. Atherosclerosis is characterized as an inflammatory chronic disease which is caused by the formation of lesions in the arterial wall. Subsequently, lesion progression and disruption ultimately lead to heart disease and stroke. The development of atherosclerosis is the underlying cause of approximately 50% of all deaths in westernized societies. Countless studies have aimed to improve therapeutic approaches for atherosclerosis treatment; however, it remains high on the global list of challenges toward healthy and long lives. Some patients with familial hypercholesterolemia could not get intended LDL-C goals even with high doses of traditional therapies such as statins, with many of them being unable to tolerate statins because of the harsh side effects. Furthermore, even in patients achieving target LDL-C levels, the residual risk of traditional therapies is still significant thus highlighting the necessity of ongoing research for more effective therapeutic approaches with minimal side effects. Decoy-based drug candidates represent an opportunity to inhibit regulatory pathways that promote atherosclerosis. In this review, the potential roles of decoys in the treatment of atherosclerosis were described based on the in vitro and in vivo findings.

TL1A/TNFR2 Axis Enhances Immunoregulatory Effects of Bone Marrow Derived Mesenchymal Stem Cell by Indian Hedgehog Signaling Pathway

Background and Objectives

The immunomodulatory potential of mesenchymal stem cells (MSCs) can be regulated by a variety of molecules, especially cytokines. The inflammatory cytokine, TNF-like ligand 1A (TL1A), has been reported as an inflammation stimulator in-multiple autoimmune diseases. Here, we studied the effects of TL1A/TNF-receptor 2 (TNFR2) pathway on the therapeutic potency of bone marrow-derived MSCs (BMSCs).

Methods and Results

BMSCs, fibroblast-like synoviocytes (FLSs), and H9 and jurkat human T lymphocytes were used in this study. BMSCs paracrine activities, differentiation, proliferation, and migration were investigated after stimulation with TL1A, and intervened with anti-TNFR2. Additionally, the effects of TL1A on BMSCs therapeutic potency were evaluated by treating RA-FLSs, and H9 and jurkat T cells with TL1A-stimulated BMSCs conditioned medium (CM). Indian hedgehog (IHH) involvement was determined by gene silencing and treatment by recombinant IHH (rIHH). TL1A induced BMSCs stemness-related genes, COX-2, IL-6, IDO, TGF-β and HGF through TNFR2. Also, TL1A corrected biased differentiation and increased proliferation, and migration through TNFR2. Meanwhile, CM of TL1A-stimulated BMSCs decreased the inflammatory markers of RA-FLSs and T cells. Moreover, TL1A-stimulated BMSCs experienced IHH up-regulation coupled with NF-κB and STAT3 signaling up-regulation, while p53 and oxidative stress were down-regulated. Furthermore, treatment of BMSCs by rIHH increased their anti-inflammatory effects. More importantly, knockdown of IHH decreased the ability of TL1A-stimulated BMSCs to alleviating the inflammation in RA-FLSs and T cells.

Conclusions

This study reports the effects of TL1A/TNFR2 pathway on the biological behaviors and therapeutic potency of BMSCs through IHH. These findings could introduce novel procedures to increase the stemness of MSCs in cellular therapy.

Antioxidant Carbon Nanoparticles Inhibit Fibroblast-Like Synoviocyte Invasiveness and Reduce Disease Severity in a Rat Model of Rheumatoid Arthritis

Reactive oxygen species have been involved in the pathogenesis of rheumatoid arthritis (RA). Our goal was to determine the effects of selectively scavenging superoxide (O2•-) and hydroxyl radicals with antioxidant nanoparticles, called poly(ethylene glycol)-functionalized hydrophilic carbon clusters (PEG-HCCs), on the pathogenic functions of fibroblast-like synoviocytes (FLS) from patients with rheumatoid arthritis (RA) and on the progression of an animal model of RA. We used human FLS from patients with RA to determine PEG-HCC internalization and effects on FLS cytotoxicity, invasiveness, proliferation, and production of proteases. We used the pristane-induced arthritis (PIA) rat model of RA to assess the benefits of PEG-HCCs on reducing disease severity. PEG-HCCs were internalized by RA-FLS, reduced their intracellular O2•-, and reduced multiple measures of their pathogenicity in vitro, including proliferation and invasion. In PIA, PEG-HCCs caused a 65% reduction in disease severity, as measured by a standardized scoring system of paw inflammation and caused a significant reduction in bone and tissue damage, and circulating rheumatoid factor. PEG-HCCs did not induce lymphopenia during PIA. Our study demonstrated a role for O2•- and hydroxyl radicals in the pathogenesis of a rat model of RA and showed efficacy of PEG-HCCs in treating a rat model of RA.

Potential role of mitochondria in synoviocytes

Synoviocytes are located in the synovium lining layer, which is composed of macrophage-like synoviocytes (MLS) and fibroblast-like synoviocytes (FLS) with different characteristics. Mitochondria, which exist in most cells, are two membrane-covered organelles. In addition to providing the necessary ATP for synoviocytes, mitochondria are involved in the regulation of redox homeostasis and the integration of synoviocytes death signals. In recent years, mitochondrial dysfunction has been found in rheumatoid arthritis (RA) and osteoarthritis (OA). Interestingly, recent studies have started uncovering that mitochondria that were previously reported to play a role in chondrocytes or immune cells, but not known to have pronounced roles in synoviocytes, can actually play crucial roles in the regulation of the pathological properties of the synoviocytes. The purpose of this review is to summarize our current understanding of the key role of mitochondria in synoviocytes, including mitochondrial dysfunction in synoviocytes can induce and aggravate inflammatory responses and changes in mitochondrial structure and function with the involvement of multiple cytokines, signal pathway, and hypoxic state of synovial tissue alter the response of synoviocytes to apoptotic stimulation. Also, mitochondrial abnormalities in synoviocytes promote the synoviocytes invasion and proliferation.

Indian Hedgehog regulates senescence in bone marrow-derived mesenchymal stem cell through modulation of ROS/mTOR/4EBP1, p70S6K1/2 pathway

Premature senescence of bone marrow-derived mesenchymal stem cells (BMSC) remains a major concern for their application clinically. Hedgehog signaling has been reported to regulate aging-associated markers and MSC skewed differentiation. Indian Hedgehog (IHH) is a ligand of Hedgehog intracellular pathway considered as an inducer in chondrogenesis of human BMSC. However, the role of IHH in the aging of BMSC is still unclear. This study explored the role IHH in the senescence of BMSC obtained from human samples and senescent mice. Isolated BMSC were transfected with IHH siRNA or incubated with exogenous IHH protein and the mechanisms of aging and differentiation investigated. Moreover, the interactions between IHH, and mammalian target of rapamycin (mTOR) and reactive oxygen species (ROS) were evaluated using the corresponding inhibitors and antioxidants. BMSC transfected with IHH siRNA showed characteristics of senescence-associated features including increased senescence-associated β-galactosidase activity (SA-β-gal), induction of cell cycle inhibitors (p53/p16), development of senescence-associated secretory phenotype (SASP), activation of ROS and mTOR pathways as well as the promotion of skewed differentiation. Interestingly, BMSC treatment with IHH protein reversed the senescence markers and corrected biased differentiation. Moreover, IHH shortage-induced senescence signs were compromised after mTOR and ROS inhibition. Our findings presented anti-aging activity for IHH in BMSC through down-regulation of ROS/mTOR pathways. This discovery might contribute to increasing the therapeutic, immunomodulatory and regenerative potency of BMSC and introduce a novel remedy in the management of aging-related diseases.