scholarly journals Smac BV6 Has Proapoptotic and Anti-Inflammatory Effects on Rheumatoid Arthritis Fibroblast-Like Synoviocytes Activated by TLR9 Ligand

Author(s):  
donatella lattuada ◽  
Claudia Casnici ◽  
Katia Crotta ◽  
Ornella marelli

Abstract Rheumatoid arthritis synovial fibroblasts (RASF) are one of the most important cells contributing reumathoid artritis (RA) pathogenesis. The critical role of the Toll-like receptor in inflammation and on autoimmune disease is not fully known. Data rising predominantly from human patients and animal models of autoimmune disease indicate that inappropriate triggering of TLR pathways by exogenous or endogenous ligands may cause the initiation and/or perpetuation of autoimmune reactions and tissue damage. Particularly, the role of TLR9 in RA is still a subject of debate and among TLRs, TLR9 is the only receptor which detects unmethylated CpG motifs in DNA (ODN), and is located intracellularly in endosomes and endoplasmic reticulum. RASFs stimulated by ODN are apoptosis-resistant and contribute to the pathogenesis of RA by producing cytokines and proteolytic enzymes, which degrade the extracellular matrix. Then, we evaluated the proapoptotic and anti-inflammatory activity of the smac BV6 on RASF cultured in synovial fluid (SF), to reproduce the physiopathological environmental characteristics of RA joints. Furthermore, BV6 induces a significant inhibition of the secretion of IL15, TNF alpha, IL6, stimulation of pannus formation, and damage of bone and cartilage in RA. Moreover the secretion of the anti-inflammatory cytokine IL10 and the cleavage of capase 3 and 8 are dramatically increased in the presence of BV6. Furthermore, TLR9 elicited a robust IFN induction and we reported that in RASF treated with ODN and BV6 the expression of IRF7 is enhanced. Our observations demonstrate that BV6 has beneficial regulatory effects on the inflammatory state induced by TLR9 activation.

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
D. Lattuada ◽  
R. Gualtierotti ◽  
K. Crotta ◽  
P. Seneci ◽  
F. Ingegnoli ◽  
...  

Rheumatoid arthritis (RA) is characterized by synovial inflammation and hyperplasia. Fibroblast-like synoviocytes (FLSs) are apoptosis-resistant and contribute to the pathogenesis of RA by producing cytokines and proteolytic enzymes, which degrade the extracellular matrix. We evaluated the proapoptotic and anti-inflammatory activity of the small molecule Smac127 on RA-FLSs cultured in synovial fluid (SF), in order to reproduce the physiopathological environmental characteristic of RA joints. In this context, Smac127 induces apoptosis by inhibiting apoptosis proteins (IAPs). This inhibition activates caspase 3 and restores the apoptotic pathway. In addition, Smac127 induces a significant inhibition of the secretion of IL-15 and IL-6, stimulation of pannus formation, and damage of bone and cartilage in RA. Also the secretion of the anti-inflammatory cytokine IL-10 is dramatically increased in the presence of Smac127. The cartilage destruction in RA patients is partly mediated by metalloproteinases; here we show that the MMP-1 production by fibroblasts cultured in SF is significantly antagonized by Smac127. Conversely, this molecule has no significant effects on RANKL and OPG production. Our observations demonstrate that Smac127 has beneficial regulatory effects on inflammatory state of RA-FLSs and suggest a potential use of Smac127 for the control of inflammation and disease progression in RA.


2019 ◽  
Vol 26 (5) ◽  
pp. 837-854 ◽  
Author(s):  
Effimia Zacharia ◽  
Nikolaos Papageorgiou ◽  
Adam Ioannou ◽  
Gerasimos Siasos ◽  
Spyridon Papaioannou ◽  
...  

During the last few years, a significant number of studies have attempted to clarify the underlying mechanisms that lead to the presentation of atrial fibrillation (AF). Inflammation is a key component of the pathophysiological processes that lead to the development of AF; the amplification of inflammatory pathways triggers AF, and, in tandem, AF increases the inflammatory state. Indeed, the plasma levels of several inflammatory biomarkers are elevated in patients with AF. In addition, the levels of specific inflammatory biomarkers may provide information regarding to the AF duration. Several small studies have assessed the role of anti-inflammatory treatment in atrial fibrillation but the results have been contradictory. Large-scale studies are needed to evaluate the role of inflammation in AF and whether anti-inflammatory medications should be routinely administered to patients with AF.


2005 ◽  
Vol 11 (5) ◽  
pp. 563-568 ◽  
Author(s):  
Ingmar Meinecke ◽  
Edita Rutkauskaite ◽  
Steffen Gay ◽  
Thomas Pap

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Gerry K. Schwalfenberg

This paper looks at the environmental role of vitamin D and solar radiation as risk reduction factors in autoimmune disease. Five diseases are considered: multiple sclerosis, type 1 diabetes, rheumatoid arthritis, autoimmune disease of the thyroid, and inflammatory bowel disease. Clinical relevant studies and factors that may indicate evidence that autoimmune disease is a vitamin D-sensitive disease are presented. Studies that have resulted in prevention or amelioration of some autoimmune disease are discussed. An example of the utility of supplementing vitamin D in an unusual autoimmune disease, idiopathic thrombocytic purpura, is presented.


2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 1484.1-1484
Author(s):  
S. Ahmed ◽  
E. Nikiphorou ◽  
J. Bayliss

Background:The role of dietary salt consumption in the etiopathogenesis of Rheumatoid Arthritis (RA), and autoimmune disease in general, has received renewed interest. This has been fueled by the increased prevalence of autoimmune disease worldwide correlating with western diets and heightened consumption of salt rich foods and also studies at the cellular level demonstrating induction of IL 17 producing T helper cells (Th17) by dietary salt.Objectives:To conduct a narrative review of observational studies and clinical trials on the role of dietary salt as an environmental risk factor for the onset and development of RA.Methods:A comprehensive search was done of the literature from 2010 to 2021, using the search terms dietary salt and RA; the native interfaces EBSCO and Ovid were used. Databases searched included Pubmed, Embase, EMCare, Medline and CINAHL using a Population, Exposure and Outcome framework; the MESH terms RA, risk factors, nutrition and salt were used. Data was extracted by an independent reviewer.Results:Out of the 72 studies initially identified, 50 were included in this review. Studies in murine models have demonstrated that high concentrations of sodium chloride promote the differentiation of T helper lymphocytes, via the serum- and glucocorticoid- inducible kinase 1 (SGK1) mediator towards the proinflammatory Th17 driven immune response. Six studies were carried out in human subjects. Study design ranged from cross sectional observational to nested case control studies. Sodium intake amongst participants characterized as having high intake, or being placed in the higher quartiles, ranged from 4.5-5grams per day. 5 out of 6 studies demonstrated that increased dietary salt consumption is associated with earlier onset RA. One study suggested an association between high salt intake and erosive disease at diagnosis and the development of anti-citrullinated protein antibodies (ACPA), although evidence was weak and from a single study only. Another study found that increased consumption of salt was only associated with risk of RA in smokers, highlighting the need to explore confounding variables further.Conclusion:This narrative review of the literature provides some evidence that supports a role of excess dietary salt consumption as a risk factor for the onset and severity of RA.Disclosure of Interests:None declared


2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 1054.1-1054
Author(s):  
M. Schmeller ◽  
M. Diller ◽  
R. Hasseli ◽  
A. Knothe ◽  
S. Rehart ◽  
...  

Background:One of the key mechanisms in the pathogenesis of rheumatoid arthritis (RA) is the interaction of macrophages and synovial fibroblasts during joint inflammation. Increased synergistic proinflammatory activity of both cell types leads to the release of high levels of proinflammatory cytokines, especially of interleukin-6 (IL-6), and of matrix degrading enzymes. If this mechanism is uncontrolled, progressive destruction of articular cartilage and bone will take place.In active disease, immediate anti-inflammatory treatment with glucocorticoids is usually replaced by disease-modifying anti-rheumatic drugs (DMARDS), especially by methotrexate (MTX) and biologics such as TNF-α- or IL-6-inhibitors. This led to great improvements in prognosis and outcome for RA patients. However, about 40% of patients experience no remission or suffer from side effects of medication. To optimize established substances and to develop new treatment strategies, it is necessary to understand the mechanisms underlying the limited therapeutic effects.Objectives:Evaluation of the effect of prednisolone, MTX, adalimumab, tocilizumab on IL-6 secretion by RA synovial fibroblasts (RASF) and macrophages.Methods:RA synovium was used for RASF isolation. Peripheral blood mononuclear cells (PBMCs) were isolated from blood of healthy donors and RA patients by using Ficoll© medium followed by density gradient centrifugation. Mononuclear cells were seeded on six well plates (6x10^6/well) and incubated for one week. Then they were stimulated with Interferon-у (20 ng/ml) and LPS (50 ng/ml) for 48h to initiate differentiation into proinflammatory M1 macrophages. The M1 macrophages were co-cultured with RASF (100.000/well) and different treatments added (prednisolone: 10, 25, 50, 75, 100 nM, 1 µM; adalimumab: 100, 500 µg/ml; tocilizumab: 1, 5 µg/ml; MTX: 0,5, 1, 5, 10, 100 nM, 1µM). After 24h culture supernatants were collected and IL-6- and TNFα-ELISAs were performed.Results:IL-6 concentrations of untreated controls were comparable, regardless whether M1 macrophages from healthy donors or RA-patients were used for co-culture. Prednisolone reduced co-culture-induced IL-6 up to 56% (p<0.001) in co-culture of RASF and M1 macrophages of healthy donors and up to 60% (p<0.001) in co-culture of RASF and RA M1 macrophages. Adalimumab reduced IL-6 up to 28% (p<0.05) in M1 of healthy donors and up to 45% (p<0.01) in RA M1 macrophage co-cultures. A minor reduction by 10-20% of IL-6 was observed with tocilizumab and no significant effect could be achieved after treatment with MTX.Conclusion:Prednisolone and adalimumab clearly decrease but do not eliminate proinflammatory synergistic activity of RASF and M1 macrophages. These results confirm the clinical observation, that there is a large number of RA-patients that independent of anti-inflammatory treatment still suffer from low-level joint inflammation.The synergistic proinflammatory activity of M1 macrophages and RASF seems to be a complex and multifactorial mechanism that is difficult to eliminate by a single treatment substance. Since it is one of the key mechanisms in RA pathogenesis, there is a critical need to investigate how therapy effects could be optimized. This study confirmed RASFs as one of the leading effector cells of increased synergistic proinflammatory activity, thus underlining their promising role as a treatment target in rheumatoid arthritis.Disclosure of Interests:None declared


2006 ◽  
Vol 203 (2) ◽  
pp. 325-335 ◽  
Author(s):  
Tetsuya Honda ◽  
Eri Segi-Nishida ◽  
Yoshiki Miyachi ◽  
Shuh Narumiya

Prostaglandin (PG)I2 (prostacyclin [PGI]) and PGE2 are abundantly present in the synovial fluid of rheumatoid arthritis (RA) patients. Although the role of PGE2 in RA has been well studied, how much PGI2 contributes to RA is little known. To examine this issue, we backcrossed mice lacking the PGI receptor (IP) to the DBA/1J strain and subjected them to collagen-induced arthritis (CIA). IP-deficient (IP−/−) mice exhibited significant reduction in arthritic scores compared with wild-type (WT) mice, despite anti-collagen antibody production and complement activation similar to WT mice. IP−/− mice also showed significant reduction in contents of proinflammatory cytokines, such as interleukin (IL)-6 in arthritic paws. Consistently, the addition of an IP agonist to cultured synovial fibroblasts significantly enhanced IL-6 production and induced expression of other arthritis-related genes. On the other hand, loss or inhibition of each PGE receptor subtype alone did not affect elicitation of inflammation in CIA. However, a partial but significant suppression of CIA was achieved by the combined inhibition of EP2 and EP4. Our results show significant roles of both PGI2-IP and PGE2-EP2/EP4 signaling in the development of CIA, and suggest that inhibition of PGE2 synthesis alone may not be sufficient for suppression of RA symptoms.


2019 ◽  
Author(s):  
Suchita Singh ◽  
Rakesh Arya ◽  
Rhishikesh R Bargaje ◽  
Mrinal Kumar Das ◽  
Subia Akram ◽  
...  

AbstractA diet derived agent Curcumin (Diferuloylmethane), demonstrated its clinical application in inflammation, infection and cancer conditions. Nevertheless, its impact on the proteome of epithelial cells of non-small cell lung carcinoma (NSCLC) is yet to be explored. We employed a stable isotope labeling method for cell culture (SILAC) based relative quantitative proteomics and informatics analysis to comprehend global proteome change in A549 cells treated with curcumin and/or Lipopolysaccharide (LPS). Pretreated A549 cells were infected with Mycobacterium tuberculosis H37Rv strain to monitor bacterial load. With exposure to curcumin and LPS, out of the 1492 identified proteins, 305 and 346 proteins showed deregulation respectively. The expression of BID and AIFM1 mitochondrial proteins which play critical role in apoptotic pathway were deregulated in curcumin treated cells. Higher mitochondria intensity was observed in curcumin treated A549 cells than LPS treatment. Simultaneous treatment of curcumin and LPS neutralized the effect of LPS. Curcumin and/or LPS pretreated A549 cells infected with H37Rv, showed successful bacterial internalization. LPS treated A549 cells after infection showed increased bacterial load than curcumin compared to non-treated infected cells. However, simultaneous treatment of curcumin and LPS neutralized the effect of LPS. This study generated molecular evidence to deepen our understanding of the anti-inflammatory role of curcumin and may be useful to identify molecular targets for drug discovery.


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