scholarly journals The Role of Flavonoids in Inhibiting Th17 Responses in Inflammatory Arthritis

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Dimitra Kelepouri ◽  
Athanasios Mavropoulos ◽  
Dimitrios P. Bogdanos ◽  
Lazaros I. Sakkas

Flavonoids have been considered powerful anti-inflammatory agents, and their exact immunomodulatory action as therapeutic agents in autoimmune diseases has started to emerge. Their role in the manipulation of immunoregulation is less understood. Several studies attempted to investigate the role of various flavonoids mainly in experimental models of autoimmune diseases, especially in the context of their potential effect on the increase of regulatory T cells (Tregs) and their ability to stimulate an overexpression of anti-inflammatory cytokines, in particular that of IL-10. The emergence of IL-17, a cytokine largely produced by Th17 cells, as a powerful proinflammatory stimulus which attenuates the induction of Tregs has prompted a series of studies investigating the role of flavonoids on Th17 cells in experimental models as well as human autoimmune diseases. This review thoroughly discusses accumulated data on the role of flavonoids on Th17 in rheumatoid arthritis and experimental autoimmune arthritis.

2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
Ning Qu ◽  
Mingli Xu ◽  
Izuru Mizoguchi ◽  
Jun-ichi Furusawa ◽  
Kotaro Kaneko ◽  
...  

T-helper 17 (Th17) cells are characterized by producing interleukin-17 (IL-17, also called IL-17A), IL-17F, IL-21, and IL-22 and potentially TNF-α and IL-6 upon certain stimulation. IL-23, which promotes Th17 cell development, as well as IL-17 and IL-22 produced by the Th17 cells plays essential roles in various inflammatory diseases, such as experimental autoimmune encephalomyelitis, rheumatoid arthritis, colitis, and Concanavalin A-induced hepatitis. In this review, we summarize the characteristics of the functional role of Th17 cells, with particular focus on the Th17 cell-related cytokines such as IL-17, IL-22, and IL-23, in mouse models and human inflammatory diseases.


2021 ◽  
Vol 12 ◽  
Author(s):  
Gary P. Brennan ◽  
Megan M. Garcia-Curran ◽  
Katelin P. Patterson ◽  
Renhao Luo ◽  
Tallie Z. Baram

Background and Rationale: Bi-directional neuronal-glial communication is a critical mediator of normal brain function and is disrupted in the epileptic brain. The potential role of aberrant microglia and astrocyte function during epileptogenesis is important because the mediators involved provide tangible targets for intervention and prevention of epilepsy. Glial activation is intrinsically involved in the generation of childhood febrile seizures (FS), and prolonged FS (febrile status epilepticus, FSE) antecede a proportion of adult temporal lobe epilepsy (TLE). Because TLE is often refractory to treatment and accompanied by significant memory and emotional difficulties, we probed the role of disruptions of glial-neuronal networks in the epileptogenesis that follows experimental FSE (eFSE).Methods: We performed a multi-pronged examination of neuronal-glia communication and the resulting activation of molecular signaling cascades in these cell types following eFSE in immature mice and rats. Specifically, we examined pathways involving cytokines, microRNAs, high mobility group B-1 (HMGB1) and the prostaglandin E2 signaling. We aimed to block epileptogenesis using network-specific interventions as well as via a global anti-inflammatory approach using dexamethasone.Results: (A) eFSE elicited a strong inflammatory response with rapid and sustained upregulation of pro-inflammatory cytokines. (B) Within minutes of the end of the eFSE, HMGB1 translocated from neuronal nuclei to dendrites, en route to the extracellular space and glial Toll-like receptors. Administration of an HMGB1 blocker to eFSE rat pups did not decrease expression of downstream inflammatory cascades and led to unacceptable side effects. (C) Prolonged seizure-like activity caused overall microRNA-124 (miR-124) levels to plunge in hippocampus and release of this microRNA from neurons via extra-cellular vesicles. (D) Within hours of eFSE, structural astrocyte and microglia activation was associated not only with cytokine production, but also with activation of the PGE2 cascade. However, administration of TG6-10-1, a blocker of the PGE2 receptor EP2 had little effect on spike-series provoked by eFSE. (E) In contrast to the failure of selective interventions, a 3-day treatment of eFSE–experiencing rat pups with the broad anti-inflammatory drug dexamethasone attenuated eFSE-provoked pro-epileptogenic EEG changes.Conclusions: eFSE, a provoker of TLE-like epilepsy in rodents leads to multiple and rapid disruptions of interconnected glial-neuronal networks, with a likely important role in epileptogenesis. The intricate, cell-specific and homeostatic interplays among these networks constitute a serious challenge to effective selective interventions that aim to prevent epilepsy. In contrast, a broad suppression of glial-neuronal dysfunction holds promise for mitigating FSE-induced hyperexcitability and epileptogenesis in experimental models and in humans.


Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Dan Ye ◽  
Yun Xu

Both resident microglia and infiltrated peripheral T cells have been proved to play important roles in the pathology of stroke. It is well accepted that activated microglia exert dual roles, including pro-inflammatory (M1) and anti-inflammatory (M2) functions. However, the mechanism regulating microglial polarization remains elusive. T cells are recruited into the ischemic area within 24 h after stroke, which also exhibit pro-inflammatory (Th1, Th17) and anti-inflammatory (Th2, Treg) functions. The interaction between microglia and T cells after stroke is barely understood, which may be served as modifiers of pathobiology in stroke. Here we described the role of T cells in the microglial polarization in mouse experimental stroke. We isolated T cells from spleens of MCAO mice at 24 h and 72 h, respectively, and then added to cultured microglia for 24 h. Our results indicated that splenic T cells obtained at 24 h after MCAO selectively promoted microglia polarize to a pro-inflammatory (M1) state, while T cells obtained at 72 h, favored microglia polarize to an anti-inflammatory (M2) state. The results of flow cytometry showed that Th1 and Th17 cells increased at 24 h after MCAO while Th2 and Treg cells increased at 72 h after MCAO. This study implicates that distinct subtypes of T cells contribute differentially to microglial polarization after stroke onset. Therefore, treatments aiming at modulating the ratios of T cells to anti-inflammatory cells have the potential to induce microglial polarize to M2 phenotype and improve the outcome of ischemic stroke.


2019 ◽  
Vol 16 (1) ◽  
Author(s):  
Tian Niu ◽  
Lu Cheng ◽  
Hanying Wang ◽  
Shaopin Zhu ◽  
Xiaolu Yang ◽  
...  

Abstract Background Uveitis is a potentially sight-threatening form of ocular inflammation that affects the uvea in the wall of the eye. Currently available treatments for uveitis have exhibited profound adverse side effects. However, KS23 is a novel 23-amino-acid anti-inflammatory peptide derived from adiponectin that may have the capability to function as a safe alternative to these existing treatment options. We, therefore, evaluated the preventive effect of KS23 in experimental autoimmune uveitis (EAU). Methods EAU was induced in mice via immunization with the peptide interphotoreceptor retinoid binding protein 161–180 (IRBP161–180). KS23 was then administered every 2 days via intraperitoneal injection to induce protection against EAU. Clinical and histopathological scores were employed to evaluate the disease progression. Inflammatory cytokines were also quantified using ELISA, and the expression levels of specific chemokines and chemokine receptors were assessed via qRT-PCR. In addition, the proportions of Th1 and Th17 cells were detected via flow cytometry, and the expression levels of specific proteins were quantified from the retina of mice using western blot analysis, to elucidate the specific mechanism of action employed by KS23 to suppress the inflammation associated with EAU. Results KS23 was found to significantly improve EAU-associated histopathological scores, while decreasing the expression of pro-inflammatory cytokines (IFN-γ, TNF-α, IL-6, and IL-17A), chemokines (LARC, RANTES, MIG, IP-10), and chemokine receptors (CCR6 and CXCR3). The proportions of Th1 and Th17 cells were also suppressed following intraperitoneal injection with KS23. The anti-inflammatory mechanism employed by KS23 was determined to be associated with the activation of AMPK and subsequent inhibition of NF-κB. Conclusions KS23 decreased the proportions of Th1 and Th17 cells to effectively ameliorate the progression of EAU. It may, therefore, serve as a promising potential therapeutic agent for uveitis.


2009 ◽  
Vol 182 (5) ◽  
pp. 3183-3190 ◽  
Author(s):  
Yan Ke ◽  
Ke Liu ◽  
Guo-Qiang Huang ◽  
Yan Cui ◽  
Henry J. Kaplan ◽  
...  

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 2968-2968
Author(s):  
Florent Malard ◽  
Céline Bossard ◽  
Jessy Arbez ◽  
Patrice Chevallier ◽  
Thierry Guillaume ◽  
...  

Abstract Abstract 2968 Background. Acute GVHD after allogeneic stem cell transplantation (allo-SCT) is an exaggerated immune response against alloantigens involving dysregulation of inflammatory cytokine cascades. Previous studies established an important role of Th1 cells in acute GVHD pathophysiology. However, the identification of proinflammatory Th17 cells which contribute to autoimmune diseases pathophysiology, raised the issue of the role of Th17 cells in human acute GVHD. Indeed, the contribution of Th17 cells in acute GVHD was assessed in GVHD mouse models with conflicting results. In addition, the role of the PDC subset (the professional type I IFN-secreting cells), which play an important role in triggering Th17-related cytokines and autoimmune diseases, is not yet established in the acute GVHD setting. This report investigated the role of Th17 cells and their interaction with PDC in gastrointestinal (GI) biopsies taken from patients with or without acute GVHD. Patients and Methods. Studies described in this report were performed in a single centre series of 21 patients who underwent allo-SCT for different hematological malignancies (n=19) and severe aplastic anemia (n=2). The median age of patients was 53 years (range, 16–69). The stem cell source was PBSCs in 19 cases (85%), CB in 2 cases and BM in one case. Ten patients received transplant from a matched-related donor, and 11 patients from a matched-unrelated donor. A reduced-intensity conditioning regimen was used in the majority of cases (n=19; 90%) Immunohistochemistry was performed on deparaffinized tissues sections using an indirect immunoperoxydase method. A quantitative evaluation of antigens expression was performed by counting the number of positive cells in the whole biopsy at 200 magnifications for each sample. Results. In this cohort, based on standard pathology criteria, 16 patients had a histologically proven gastrointestinal acute GVHD. In all cases, biopsies were taken before initiation of systemic corticosteroid therapy. The remaining 5 patients did not have histological signs of acute GVHD (and did not develop clinical signs of acute GVHD) and thus, were used as controls. In order to identify the Th17 cell population, biopsies were tested for expression of the CD161 and CCR6 markers, and ROR-gamma-t, the key transcription factor that orchestrates the differentiation of Th17 cells. Significantly higher numbers of ROR-gamma-t+ and CD161+ cells were counted in the intestinal mucosa of patients with acute GVHD compared with intestinal mucosa of patients without acute GVHD, mainly found in the lamina propria but also in the epithelium of altered glands (p=0.016 and p=0.009 for ROR-gamma-t and CD161 expression respectively). Given the role of PDCs in triggering Th17-related cytokines, we sought next to determine the proportion of PDCs in intestinal biopsies from these same patients. This analysis showed a significant increase of CD123+ PDCs in the intestinal mucosa of patients with acute GVHD compared with mucosa of patients without acute GVHD (p=0.017). Moreover, we observed a significant correlation between the number of CD123+ PDCs and ROR-gamma-t or CD161 expressing cells in the intestinal mucosa of acute GVHD patients, highlighting the link between PDC and Th17 cells. Conclusion. The current study shed some light on the role of Th17 cells in the context of gastro-intestinal acute GVHD. Using well-established specific markers, we show that Th17 cells infiltrate intestinal biopsies from patients with acute GVHD. In addition, Th17 infiltration was paralleled by the infiltration of PDCs, suggesting a potential new pathophysiological link between PDCs and Th17 response in the context of gastro-intestinal acute GVHD. This is consistent with studies showing that PDCs can drive the differentiation of Th17 cells. Functional analyses are currently ongoing. Although the exact mechanism that links type I IFN production to PDC-mediated Th17 responses is still unclear in acute GVHD, these data raise the prospect of future innovative approaches to optimize immunosuppression regimens for the treatment or prophylaxis of acute GVHD by targeting PDCs and the Th17 response. Disclosures: No relevant conflicts of interest to declare.


2014 ◽  
Vol 124 (1) ◽  
pp. 55-58
Author(s):  
Katarzyna Pogoda ◽  
Maria Pyszniak ◽  
Magdalena Bańka ◽  
Beata Rybojad ◽  
Jacek Tabarkiewicz

Abstract Th17 cells are newly described population of lymphoctyes, that recruits neutrophils to the site of inflammation and activate inflammatory phenotype of various tissues. They also play a pivotal role in autoimmune diseases and cancers. These cells secrete mainly different isoforms of IL-17, but also IL-21 and IL-22. Rheumatoid arthritis and juvenile idiopathic arthritis are the most common autoimmune joints’ inflammatory disease, affecting respectively adults and children. For a long time the immunopathogenesis of autoimmune diseases has been associated with Th1 lymphocytes. This hypothesis has changed after the discovery of Th17 cells, which are thought to be key mediators of autoimmune arthritides


Nutrients ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 1013 ◽  
Author(s):  
Rossana Scrivo ◽  
Carlo Perricone ◽  
Alessio Altobelli ◽  
Chiara Castellani ◽  
Lorenzo Tinti ◽  
...  

The incidence and prevalence of autoimmune diseases have increased in Western countries over the last years. The pathogenesis of these disorders is multifactorial, with a combination of genetic and environmental factors involved. Since the epidemiological changes cannot be related to genetic background, which did not change significantly in that time, the role of environmental factors has been reconsidered. Among these, dietary habits, and especially an excessive salt, typical of processed foods, has been implicated in the development of autoimmune diseases. In this review, we summarize current evidence, deriving both from experimental models and clinical studies, on the capability of excessive salt intake to exacerbate proinflammatory responses affecting the pathogenesis of immune-mediated diseases. Data on several diseases are presented, including rheumatoid arthritis, systemic lupus erythematosus, multiple sclerosis, and Crohn’s disease, with many of them supporting a proinflammatory effect of salt. Likewise, a hypertonic microenvironment showed similar effects in experimental models both in vivo and in vitro. However, murine models of spontaneous autoimmune polyneuropathy exposed to high salt diet suggest opposite outcomes. These results dictate the need to further analyse the role of cooking salt in the treatment and prevention of autoimmune diseases, trying to shape a fine tuning between the possible advantages of a restricted salt intake and the changes in circulating metabolites, mediators, and hormones which come along salt consumption and could in turn influence autoimmunity.


2007 ◽  
Vol 353 (4) ◽  
pp. 857-862 ◽  
Author(s):  
Yinan Wang ◽  
Hirayasu Kai ◽  
Fei Chang ◽  
Kai Shibata ◽  
Satoko Tahara-Hanaoka ◽  
...  

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 4103-4103
Author(s):  
Florent Malard ◽  
Céline Bossard ◽  
Patrice Chevallier ◽  
Thierry Guillaume ◽  
Jacques Delaunay ◽  
...  

Abstract Abstract 4103 Background. Acute GVHD after allogeneic stem cell transplantation (allo-SCT) is an exaggerated immune response against alloantigens involving dysregulation of inflammatory cytokine cascades. Previous studies established an important role of Th1 cells in acute GVHD pathophysiology. However, the identification of proinflammatory Th17 cells which contribute to autoimmune diseases pathophysiology, raised the issue of the role of Th17 cells in human acute GVHD. Indeed, the contribution of Th17 cells in acute GVHD was assessed in GVHD mouse models with conflicting results. In addition, the role of the PDC subset (the professional type I IFN-secreting cells), which play an important role in triggering Th17-related cytokines and autoimmune diseases, is not yet established in the acute GVHD setting. This report investigated the role of Th17 cells and their interaction with PDC in cutaneous biopsies taken from patients with or without acute GVHD. Patients and Methods. Studies described in this report were performed in a single centre series of 38 patients who underwent allo-SCT for different hematological malignancies (n=37) and severe aplastic anemia (n=1). The median age of patients was 52 years (range, 17–70). The stem cell source was PBSCs in 27 cases (71%), CB in 6 cases and BM in 5 cases. 11 patients received transplant from a matched-related donor, and 27 patients from an unrelated donor. A reduced-intensity conditioning regimen was used in the majority of cases (n=29; 76%) Immunohistochemistry was performed on deparaffinized tissues sections using an indirect immunoperoxydase method. A quantitative evaluation of antigens expression was performed by counting the number of positive cells in the whole biopsy at 200 magnifications for each sample. Results. In this cohort, based on standard pathology criteria, 29 patients had a histologically proven skin acute GVHD. In all cases, biopsies were taken before initiation of systemic corticosteroid therapy. The remaining 9 patients did not have histological signs of acute GVHD (and did not develop clinical signs of acute GVHD) and thus, were used as controls. In order to identify the Th17 cell population, biopsies were tested for expression of the CD161 and CCR6 markers, and ROR-gamma-t, the key transcription factor that orchestrates the differentiation of Th17 cells. Significantly higher numbers of ROR-gamma-t+, CD161+ and CCR6+ cells were counted in the skin of patients with acute GVHD compared with intestinal mucosa of patients without acute GVHD, mainly found in the lamina propria but also in the epithelium of altered glands (p=0.001, p<0.0001 and p=0.01 for ROR-gamma-t, CD161 and CCR6 expression respectively).Given the role of PDCs in triggering Th17-related cytokines, we sought next to determine the proportion of PDCs in cutaneous biopsies from these same patients. This analysis showed a significant increase of BDCA2+ PDCs in the skin of patients with acute GVHD compared with skin of patients without acute GVHD (p=0.03). Moreover, we observed a strong expression of the type I IFN-inducible protein Mx1 in the skin of patients with acute GVHD compared with skin of patients without acute GVHD, reflecting the high production of type I IFN by the BDCA2+ PDCs. Conclusion. The current study shed some light on the role of Th17 cells in the context of cutaneous acute GVHD. Using well-established specific markers, we show that Th17 cells infiltrate skin biopsies from patients with acute GVHD. In addition, Th17 infiltration was paralleled by the infiltration of PDCs, suggesting a potential new pathophysiological link between PDCs and Th17 response in the context of cutaneous acute GVHD. This is consistent with studies showing that PDCs can drive the differentiation of Th17 cells. Functional analyses are currently ongoing. These data raise the prospect of future innovative approaches to optimize immunosuppression regimens for the treatment or prophylaxis of acute GVHD by targeting PDCs and the Th17 response. Disclosures: No relevant conflicts of interest to declare.


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