Immune deficiency or hyperactivity-Nf-κb illuminates autoimmunity

Discovery of Ibrutinib-based BTK PROTACs with in vivo anti-inflammatory efficacy by inhibiting NF-κB activation

As a critical upstream regulator of nuclear factor-κB (NF-κB) activation, Bruton's tyrosine kinase (BTK) has been identified to be an effective therapeutic target for the treatment of acute or chronic inflammatory diseases. Herein, we describe the design, synthesis and structure-activity-relationship analysis of a novel series of Ibrutinib-based BTK PROTACs by recruiting Cereblon (CRBN) ligase. Among them, compound 15 was identified as the most potent degrader with a DC50 of 3.18 nM, significantly better than the positive control MT802 (DC50 of 63.31 nM). Compound 15 could also degrade BTK protein in Lipopolysaccharide (LPS)-stimulated RAW264.7 cells, and suppress the mRNA expression and secretion of proinflammatory cytokines such as IL-1β and IL-6 by inhibiting NF-κB activation. Furthermore, compound 15 reduced inflammatory responses in a mouse zymosan-induced peritonitis (ZIP) model. Our findings demonstrated for the first time that targeting BTK degradation by PROTACs might be an alternative option for the treatment of inflammatory disorders, and compound 15 represents one of the most efficient BTK PROTACs (DC50 = 3.18 nM; Dmax = 99.90%; near 100% degradation at 8 h) reported so far and could serve as a lead compound for further investigation as an anti-inflammatory agent.

Proposed mechanisms of action of herbal drugs and their biologically active constituents in the treatment of coughs: an overview

Various medicinal plants find their use in cough treatment, based on traditions and long-term experience. Pharmacological principles of their action, however, are much less known. Herbal drugs usually contain a mixture of potentially active compounds, which can manifest diverse effects. Expectorant or antitussive effects, which can be accompanied by others, such as anti-inflammatory or antibacterial, are probably the most important in the treatment of coughs. The aim of this review is to summarize the current state of knowledge of the effects of medicinal plants or their constituents on cough, based on reliable pharmacological studies. First, a comprehensive description of each effect is provided in order to explain the possible mechanism of action in detail. Next, the results related to individual plants and substances are summarized and critically discussed based on pharmacological in vivo and in vitro investigation.

Mechanism of the antidiabetic action of Nigella sativa and Thymoquinone: a review

Introduction

Long used in traditional medicine, Nigella sativa (NS; Ranunculaceae) has shown significant efficacy as an adjuvant therapy for diabetes mellitus (DM) management by improving glucose tolerance, decreasing hepatic gluconeogenesis, normalizing blood sugar and lipid imbalance, and stimulating insulin secretion from pancreatic cells. In this review, the pharmacological and pharmacokinetic properties of NS as a herbal diabetes medication are examined in depth, demonstrating how it counteracts oxidative stress and the onset and progression of DM.

Methods

This literature review drew on databases such as Google Scholar and PubMed and various gray literature sources using search terms like the etiology of diabetes, conventional versus herbal therapy, subclinical pharmacology, pharmacokinetics, physiology, behavior, and clinical outcomes.

Results

The efficiency and safety of NS in diabetes, notably its thymoquinone (TQ) rich volatile oil, have drawn great attention from researchers in recent years; the specific therapeutic dose has eluded determination so far. TQ has anti-diabetic, anti-inflammatory, antioxidant, and immunomodulatory properties but has not proved druggable. DM's intimate link with oxidative stress, makes NS therapy relevant since it is a potent antioxidant that energizes the cell's endogenous arsenal of antioxidant enzymes. NS attenuates insulin resistance, enhances insulin signaling, suppresses cyclooxygenase-2, upregulates insulin-like growth factor-1, and prevents endothelial dysfunction in DM.

Conclusion

The interaction of NS with mainstream drugs, gut microbiota, and probiotics opens new possibilities for innovative therapies. Despite its strong potential to treat DM, NS and TQ must be examined in more inclusive clinical studies targeting underrepresented patient populations.

Sex-Dependent Transcriptional Changes in Response to Stress in Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: A Pilot Project

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a complex, multi-symptom illness characterized by debilitating fatigue and post-exertional malaise (PEM). Numerous studies have reported sex differences at the epidemiological, cellular, and molecular levels between male and female ME/CFS patients. To gain further insight into these sex-dependent changes, we evaluated differential gene expression by RNA-sequencing (RNA-Seq) in 33 ME/CFS patients (20 female, 13 male) and 34 matched healthy controls (20 female and 14 male) before, during, and after an exercise challenge intended to provoke PEM. Our findings revealed that pathways related to immune-cell signaling (including IL-12) and natural killer cell cytotoxicity were activated as a result of exertion in the male ME/CFS cohort, while female ME/CFS patients did not show significant enough changes in gene expression to meet the criteria for the differential expression. Functional analysis during recovery from an exercise challenge showed that male ME/CFS patients had distinct changes in the regulation of specific cytokine signals (including IL-1β). Meanwhile, female ME/CFS patients had significant alterations in gene networks related to cell stress, response to herpes viruses, and NF-κβ signaling. The functional pathways and differentially expressed genes highlighted in this pilot project provide insight into the sex-specific pathophysiology of ME/CFS.

New insights into the Lck-NF-κB signaling pathway

Lck is essential for the development, activity, and proliferation of T cells, which may contribute to pathological progression and development of human diseases, such as autoimmune disorders and cancers when functioning aberrantly. Nuclear factor-κB (NF-κB) was initially discovered as a factor bound to the κ light-chain immunoglobulin enhancer in the nuclei of activated B lymphocytes. Activation of the nuclear factor-κB pathway controls expression of several genes that are related to cell survival, apoptosis, and inflammation. Abnormal expression of Lck and nuclear factor-κB has been found in autoimmune diseases and malignancies, including rheumatoid arthritis, systemic lupus erythematosus, acute T cell lymphocytic leukemia, and human chronic lymphocytic leukemia, etc. Nuclear factor-κB inhibition is effective against autoimmune diseases and malignancies through blocking inflammatory responses, although it may lead to serious adverse reactions that are unexpected and unwanted. Further investigation of the biochemical and functional interactions between nuclear factor-κB and other signaling pathways may be helpful to prevent side-effects. This review aims to clarify the Lck-nuclear factor-κB signaling pathway, and provide a basis for identification of new targets and therapeutic approaches against autoimmune diseases and malignancies.

Age-related mechanisms in the context of rheumatic disease

Ageing is characterized by a progressive loss of cellular function that leads to a decline in tissue homeostasis, increased vulnerability and adverse health outcomes. Important advances in ageing research have now identified a set of nine candidate hallmarks that are generally considered to contribute to the ageing process and that together determine the ageing phenotype, which is the clinical manifestation of age-related dysfunction in chronic diseases. Although most rheumatic diseases are not yet considered to be age related, available evidence increasingly emphasizes the prevalence of ageing hallmarks in these chronic diseases. On the basis of the current evidence relating to the molecular and cellular ageing pathways involved in rheumatic diseases, we propose that these diseases share a number of features that are observed in ageing, and that they can therefore be considered to be diseases of premature or accelerated ageing. Although more data are needed to clarify whether accelerated ageing drives the development of rheumatic diseases or whether it results from the chronic inflammatory environment, central components of age-related pathways are currently being targeted in clinical trials and may provide a new avenue of therapeutic intervention for patients with rheumatic diseases.

Probiotics as Potential Biological Immunomodulators in the Management of Oral Lichen Planus: What's New?

Oral lichen planus (OLP) is a T cell-mediated chronic inflammatory disorder with multifactorial aetiology and malignant transformation potential. Despite the treatments so far identified, new tailored and safe specific measures are needed. Recently, human microbiota imbalance has been linked to several immune-mediated diseases, opening new therapeutic perspectives for probiotics; besides their ability to directly interact with the host microbiota, they also display a strain-specific immune-modulatory effect. Thus, this non-systematic review aims to elucidate the molecular pathways underlying probiotic activity, mainly those of Lactobacilli and Bifidobacteria and their metabolites in OLP pathogenesis and malignant transformation, focusing on the most recent in vitro and in vivo research evidence. Findings related to their activity in other immune-mediated diseases are here included, suggesting a probiotic translational use in OLP. Probiotics show immune-modulatory and microbiota-balancing activities; they protect the host from pathogens, hamper an excessive effector T cell response, reduce nuclear factor-kappa B (NF-kB) signalling and basal keratinocytes abnormal apoptosis, shifting the mucosal response towards the production of anti-inflammatory cytokines, thus preventing uncontrolled damage. Therefore, probiotics could be a highly encouraging prevention and immunotherapeutic approach for a safer and more sustainable OLP management.

Hexarelin attenuates abdominal aortic aneurysm formation by inhibiting SMC phenotype switch and inflammasome activation

Hexarelin, a synthetic growth hormone-releasing peptide, is shown to be protective in cardiovascular diseases such as myocardial infraction and atherosclerosis. However, the functional role of hexarelin in abdominal aortic aneurysm (AAA) remains undefined. The present study determined the effect of hexarelin administration (200 μg/kg twice per day) in a mouse model of elastase-induced abdominal aortic aneurysm. Echocardiography and in situ pictures showed hexarelin decreased infrarenal aorta diameter. Histology staining showed elastin degradation was improved in hexarelin-treated group. Hexarelin rescued smooth muscle cell contractile phenotype with increased α-SMA and decreased MMP2. Furthermore, hexarelin inhibited inflammatory cell infiltration, NLRP3 inflammasome activation and IL-18 production. Particularly, hexarelin suppressed NF-κB signaling pathway which is a key initiator of inflammatory response. These results demonstrated that hexarelin attenuated AAA development by inhibiting SMC phenotype switch and NF-κB signaling mediated inflammatory response.

Lipid metabolism in autoimmune rheumatic disease: implications for modern and conventional therapies

Suppressing inflammation has been the primary focus of therapies in autoimmune rheumatic diseases (AIRDs), including rheumatoid arthritis and systemic lupus erythematosus. However, conventional therapies with low target specificity can have effects on cell metabolism that are less predictable. A key example is lipid metabolism; current therapies can improve or exacerbate dyslipidemia. Many conventional drugs also require in vivo metabolism for their conversion into therapeutically beneficial products; however, drug metabolism often involves the additional formation of toxic by-products, and rates of drug metabolism can be heterogeneous between patients. New therapeutic technologies and research have highlighted alternative metabolic pathways that can be more specifically targeted to reduce inflammation but also to prevent undesirable off-target metabolic consequences of conventional antiinflammatory therapies. This Review highlights the role of lipid metabolism in inflammation and in the mechanisms of action of AIRD therapeutics. Opportunities for cotherapies targeting lipid metabolism that could reduce immunometabolic complications and potential increased cardiovascular disease risk in patients with AIRDs are discussed.

Cyclopentenone Prostaglandins: Biologically Active Lipid Mediators Targeting Inflammation

Cyclopentenone prostaglandins (cyPGs) are biologically active lipid mediators, including PGA2, PGA1, PGJ2, and its metabolites. cyPGs are essential regulators of inflammation, cell proliferation, apoptosis, angiogenesis, cell migration, and stem cell activity. cyPGs biologically act on multiple cellular targets, including transcription factors and signal transduction pathways. cyPGs regulate the inflammatory response by interfering with NF-κB, AP-1, MAPK, and JAK/STAT signaling pathways via both a group of nuclear receptor peroxisome proliferator-activated receptor-gamma (PPAR-γ) dependent and PPAR-γ independent mechanisms. cyPGs promote the resolution of chronic inflammation associated with cancers and pathogen (bacterial, viral, and parasitic) infection. cyPGs exhibit potent effects on viral infections by repressing viral protein synthesis, altering viral protein glycosylation, inhibiting virus transmission, and reducing virus-induced inflammation. We summarize their anti-proliferative, pro-apoptotic, cytoprotective, antioxidant, anti-angiogenic, anti-inflammatory, pro-resolution, and anti-metastatic potential. These properties render them unique therapeutic value, especially in resolving inflammation and could be used in adjunct with other existing therapies. We also discuss other α, β -unsaturated carbonyl lipids and cyPGs like isoprostanes (IsoPs) compounds.

Structural and Biochemical Basis for Higher-Order Assembly between A20-Binding Inhibitor of NF-κB 1 (ABIN1) and M1-Linked Ubiquitins

Polyubiquitination is important in controlling NF-κB signaling. Excessive NF-κB activity has been linked to inflammatory disorders and autoimmune diseases, while ABIN1 could attenuate NF-κB activation to maintain immune homeostasis by utilizing UBAN to recognize linear (M1)-linked polyubiquitinated NF-κB activation mediators, including NEMO, IRAK1 and RIP1. PolyUb-mediated UBAN recruitment remains undetermined, since the recognition studies focused mostly on di-ubiquitin (diUb). Here we report three crystal structures of human ABIN1 UBAN (hABIN1^UBAN) in complex with M1-linked diUb, triUb, and tetraUb, respectively. Notably, the hABIN1^UBAN:diUb structure reveals that a diUb randomly binds one of the Ub-binding sites of the hABIN1^UBAN dimer and leaves the other site vacant. Together with the ITC and gel-filtration analyses, we found that M1-triUb and M1-tetraUb adopt two unique conformations, instead of an elongated one, and they preferentially use the N-terminal two-Ub unit to bind the primary Ub-binding site of a hABIN1^UBAN dimer and the C-terminal two-Ub unit to bind the secondary Ub-binding site of another hABIN1^UBAN dimer. Especially, our results suggest that two ABIN1^UBAN dimers cooperatively bind two UBAN-binding units of a tetraUb or vice versa. Since the UBAN family members share a conserved diUb-binding mode, our results suggest that M1-polyUb modification allows multiple copies of the two-tandem Ub unit to simultaneously coordinate multiple and/or different binding partners to increase their local concentrations and to facilitate the formation of a large signaling complex. Our study provides a structural-functional glimpse of M1-polyUb as a multiple-molecule binding platform to exert its intrinsic structural plasticity in mediating cellular signaling.

S100A7 promotes the development of human endometriosis by activating NF-κB signaling pathway in endometrial stromal cells

Endometriosis (EM) is a chronic inflammatory disease affecting women aged between 23 and 42 years with a prevalence of 6%-10%. S100A7, a member of the S100 protein family, has been implicated in promoting inflammation. However, the role of S100A7 in EM and its underlying mechanism remain to be elucidated. S100A7 was silenced or overexpressed in primary endometrial stromal cells (ESCs). Cell proliferation was determined using a Cell Counting Kit-8. Cell cycle/apoptosis was monitored using a flow cytometer. Cell invasion was studied by a Transwell assay. Quantitative RT-PCR and Western blot analyses were used to evaluate gene expression. S100A7 and NF-κB expression is increased in both endometriotic tissue and ESCs from women with EM. The expression of S100A7 is correlated with the expression of NF-κB. S100A7 knockdown inhibits ESCs proliferation, cell cycle progression, cell invasion, and inflammation, but promotes cell apoptosis in an NF-κB dependent manner. In contrast, S100A7 overexpression demonstrated an inverse effect. S100A7 is increased in both endometriotic tissue and ESCs from women with EM. S100A7 overexpression contributes to EM through increasing ESCs proliferation, cell cycle progression, cell invasion, and inflammation, and inhibiting cell apoptosis in the NF-κB dependent manner. These findings highlight the importance of S100A7/NF-κB signaling in EM and provide new insights into therapeutic strategies for EM.

Is nuclear sirtuin SIRT6 a master regulator of immune function?

The ability to ward off pathogens with minimal damage to the host determines the immune system's robustness. Multiple factors, including pathogen processing, identification, secretion of mediator and effector molecules, and immune cell proliferation and differentiation into various subsets, constitute the success of mounting an effective immune response. Cellular metabolism controls all of these intricate processes. Cells utilize diverse fuel sources and switch back and forth between different metabolic pathways depending on their energy needs. The three most critical metabolic pathways on which immune cells depend to meet their energy needs are oxidative metabolism, glycolysis, and glutaminolysis. Dynamic switching between these metabolic pathways is needed for optimal function of the immune cells. Moreover, switching between these metabolic pathways needs to be tightly regulated to achieve the best results. Immune cells depend on the Warburg effect for their growth, proliferation, secretory, and effector functions. Here, we hypothesize that the sirtuin, SIRT6, could be a negative regulator of the Warburg effect. We also postulate that SIRT6 could act as a master regulator of immune cell metabolism and function by regulating critical signaling pathways.

Substrate-specific recognition of IKKs mediated by USP16 facilitates autoimmune inflammation

The classic NF-κB pathway plays crucial roles in various immune responses and inflammatory diseases. Its key kinase, IKKβ, participates in a variety of pathological and physiological processes by selectively recognizing its downstream substrates, including p105, p65, and IκBα, but the specific mechanisms of these substrates are unclear. Hyperactivation of one of the substrates, p105, is closely related to the onset of inflammatory bowel disease (IBD) in Nfkb1-deficient mice. In this study, we found that IKKβ ubiquitination on lysine-238 was substantially increased during inflammation. Using mass spectrometry, we identified USP16 as an essential regulator of the IKKβ ubiquitination level that selectively affected p105 phosphorylation without directly affecting p65 or IκBα phosphorylation. Furthermore, USP16 was highly expressed in colon macrophages in patients with IBD, and myeloid-conditional USP16-knockout mice exhibited reduced IBD severity. Our study provides a new theoretical basis for IBD pathogenesis and targeted precision intervention therapy.

Artesunate inhibits Sjögren's syndrome-like autoimmune responses and BAFF-induced B cell hyperactivation via TRAF6-mediated NF-κB signaling

BACKGROUND

Hyperactivation of B cells by activators has been demonstrated to play a central role in the pathogenesis of Sjögren's syndrome (SS). In this study, we found that artesunate (ART) can attenuate BAFF-induced B cell hyperactivation and SS-like symptoms in NOD/Ltj mice.

PURPOSE

To determine the efficacy of ART in attenuating SS-like symptoms in vivo and explore the underlying mechanism in vitro.

STUDY DESIGN

ART was intragastrically injected into SS-like NOD/Ltj mice. The cytokine hsBAFF was used to activate Raji and Daudi B cells to mimic B cell hyperactivation in vitro.

METHODS

The efficacy of ART in inhibiting SS progression was studied in NOD/Ltj mice. Salivary flow rate, the number of lymphocytic infiltration foci, the level of autoantibodies and the extent of B cell infiltration were measured in the indicated groups. CCK-8 assays, flow cytometry-based EdU staining and Annexin V/PI staining were also used to detect the effect of ART on the survival and proliferation mechanism in BAFF-induced Raji and Daudi cells. Further studies determined that TRAF6 degradation is a potential mechanism by which ART determines B cell fate.

RESULTS

Treatment with ART inhibited lymphocytic foci formation, B cell infiltration and autoantibody secretion in SS-like NOD/Ltj mice. In vitro assay results indicated that ART effectively inhibited BAFF-induced viability, survival and proliferation of neoplastic B cells. Mechanistically, ART targeted BAFF-activated NFκB by regulating the proteasome-mediated degradation of TRAF6 in Raji and Daudi cells.

CONCLUSION

ART ameliorated murine SS-like symptoms and regulated TRAF6-NFκB signaling, thus determining survival and proliferation of B cells.

Thymoquinone in autoimmune diseases: Therapeutic potential and molecular mechanisms

Autoimmune diseases (AUDs) are a multifactorial disease, among which rheumatoid arthritis, systemic lupus erythematosus and multiple sclerosis are more prevalent. Several anti-inflammatory, biologics, and AUD-modifying drugs are found effective against them, but their repeated use are associated with various adverse effects. In this review article, we have focused on the regulation of inflammatory molecules, molecular signaling pathways, immune cells, and epigenetics by natural product thymoquinone on AUDs. Studies indicate that thymoquinone can regulate inflammatory molecules including interferons, interleukins, tumor necrosis factor-α (TNF-α), oxidative stress, regulatory T cells, and various signaling pathways such as nuclear factor kappa beta (NF-κβ), janus kinase/signal transduction and activator of transcription (JAK-STAT), mitogen-activated protein kinase (MAPK) at the molecular level and epigenetic alteration. As these molecules and signaling pathways with defective immune function play an important role in AUD development, controlling these molecules and deregulated molecular mechanism is a significant feature of AUD therapeutics. Interestingly thymoquinone is reported to possess all these potential. This article reviewed the deregulated mechanism of AUDs, and the action of thymoquinone on inflammatory molecules, immune cells, signaling pathways, and epigenetic machinery. Thymoquinone can be regarded as a potential drug candidate for AUD treatment.

Frailty in Rheumatic Diseases

Frailty is a syndrome characterized by the decline in the physiologic reserve and function of several systems, leading to increased vulnerability and adverse health outcomes. While common in the elderly, recent studies have underlined the higher prevalence of frailty in chronic diseases, independent of age. The pathophysiological mechanisms that contribute to frailty have not been completely understood, although significant progresses have recently been made. In this context, chronic inflammation is likely to play a pivotal role, both directly and indirectly through other systems, such as the musculoskeletal, endocrine, and neurological systems. Rheumatic diseases are characterized by chronic inflammation and accumulation of deficits during time. Therefore, studies have recently started to explore the link between frailty and rheumatic diseases, and in this review, we report what has been described so far. Frailty is dynamic and potentially reversible with 8.3%-17.9% of older adults spontaneously improving their frailty status over time. Muscle strength is likely the most significant influencing factor which could be improved with training thus pointing at the need to maintain physical activity. Not surprisingly, frailty is more prevalent in patients affected by rheumatic diseases than in healthy controls, regardless of age and is associated with high disease activity to affect the clinical outcomes, largely due to chronic inflammation. More importantly, the treatment of the underlying condition may prevent frailty. Scales to assess frailty in patients affected by rheumatic diseases have been proposed, but larger casuistries are needed to validate disease-specific indexes, which could allow more accurate prognostic estimates than demographic and disease-related variables alone. Frail patients can be more vulnerable and more difficult to treat, due to the risk of side effects, therefore frailty should be taken into account in clinical decisions. Clinical trials addressing frailty could identify patients who are less likely to tolerate potentially toxic medications and might benefit from more conservative regimens. In conclusion, the implementation of the concept of frailty in rheumatology will allow a better understanding of the patient global health, a finest risk stratification and a more individualized management strategy.

Cynanchum paniculatum and Its Major Active Constituents for Inflammatory-Related Diseases: A Review of Traditional Use, Multiple Pathway Modulations, and Clinical Applications

Cynanchum paniculatum Radix, known as Xuchangqing in Chinese, is commonly prescribed in Chinese Medicine (CM) for the treatment of various inflammatory diseases. The anti-inflammatory property of Cynanchum paniculatum can be traced from its wind-damp removing, collaterals' obstruction relieving, and toxins counteracting effects as folk medicine in CM. This paper systematically reviewed the research advancement of the pharmacological effects of Cynanchum paniculatum among a variety of human diseases, including diseases of the respiratory, circulatory, digestive, urogenital, hematopoietic, endocrine and metabolomic, neurological, skeletal, and rheumatological systems and malignant diseases. This review aims to link the long history of clinical applications of Cynanchum paniculatum in CM with recent biomedical investigations. The major bioactive chemical compositions of Cynanchum paniculatum and their associated action mechanism unveiled by biomedical investigations as well as the present clinical applications and future perspectives are discussed. The major focuses of this review are on the diverse mechanisms of Cynanchum paniculatum and the role of its active components in inflammatory diseases.

The protective effect of the TSPO ligands 2,4-Di-Cl-MGV-1, CB86, and CB204 against LPS-induced M1 pro-inflammatory activation of microglia

We have shown previously, that the 18 ​kDa translocator protein (TSPO) synthetic ligands quinazoline derivatives (2-Cl-MGV-1 and MGV-1) can inhibit activation of in BV-2 microglial cells. In the present study we assessed the impact of novel TSPO ligands on lipopolysaccharide (LPS)-induced microglial activation as expressed by release of pro-inflammatory molecules, including cytokines [interleukin-6 (IL-6), IL-1β, interferon- γ (IFN-γ)] nitric oxide (NO), CD8, and cyclo-oxygenase-2 (COX-2). The TSPO ligands 2,4-Di-Cl-MGV-1, CB86, and CB204 counteracted with the LPS-induced microglial activation. Exposure to LPS along with the TSPO ligand 2,4-Di-Cl-MGV-1 (25 ​μM) reduced significantly the release of NO by 24-, IL-6 by 14-, IL-β by 14-, IFN- γ by 6-, and TNF-α by 29-folds, respectively. In contrast to the anti-neuroinflammatory effect of the TSPO ligands, the effect of diclofenac sodium (DS; 25 ​μM) did not reach statistical significance. No alterations in IL-10 and IL-13 were detected (M2 anti-inflammatory pathway) during the inhibition of M1 pro-inflammatory pathway.

New cassane-type diterpenoids from kernels of Caesalpinia bonduc (Linn.) Roxb. and their inhibitory activities on phosphodiesterase (PDE) and nuclear factor-kappa B (NF-κB) expression

In this paper, chemical investigation on the chloroform soluble fraction of seed kernels of Caesalpinia bonduc resulted in the isolation of five new cassane diterpenoids: norcaesalpinin O (1), norcaesalpinin P (2), caesalpinin MQ (3), caesall O/P (4/5) and seven known compounds (6-12). Compounds structures were elucidated by ¹H NMR, ¹³C NMR, 2D NMR, HR-MS and ECD (electronic circular dichroism) spectral analysis. The characters for new compounds with the presence of an aromatized C ring or demethyl group at C-17 position in the structures were found. By means of bioactive screenings, the inhibitory effect on type-4 phosphodiesterase (PDE4, the target protein of asthma disease) and nuclear factor-kappa B (NF-κB) expression were valued. Compound 1 was found to exhibit moderate inhibitory activity on PDE4 and much better binding affinity than other structures by docking studies for interaction analyzing. Compounds 6, 10 and 11 displayed considerable inhibitory strength against NF-κB expression with inhibitory ratio 48.6%, 42.9% and 37.1% at 10 µM, respectively. The isolation of cassane-type diterpenoids with anti-inflammation activity from C. bonduc implied that this plant might be a good source for anti-inflammation agents finding.

Altered inflammasome machinery as a key player in the perpetuation of Rett syndrome oxinflammation

Rett syndrome (RTT) is a progressive neurodevelopmental disorder mainly caused by mutations in the X-linked MECP2 gene. RTT patients show multisystem disturbances associated with an oxinflammatory status. Inflammasomes are multi-protein complexes, responsible for host immune responses against pathogen infections and redox-related cellular stress. Assembly of NLRP3/ASC inflammasome triggers pro-caspase-1 activation, thus, resulting in IL-1β and IL-18 maturation. However, an aberrant activation of inflammasome system has been implicated in several human diseases. Our aim was to investigate the possible role of inflammasome in the chronic subclinical inflammatory condition typical of RTT, by analyzing this complex in basal and lipopolysaccharide (LPS)+ATP-stimulated primary fibroblasts, as well as in serum from RTT patients and healthy volunteers. RTT cells showed increased levels of nuclear p65 and ASC proteins, pro-IL-1β mRNA, and NLRP3/ASC interaction in basal condition, without any further response upon the LPS + ATP stimuli. Moreover, augmented levels of circulating ASC and IL-18 proteins were found in serum of RTT patients, which are likely able to amplify the inflammatory response. Taken together, our findings suggest that RTT patients exhibited a challenged inflammasome machinery at cellular and systemic level, which may contribute to the subclinical inflammatory state feedback observed in this pathology.

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RTT cell shows a constitutive NFκB activation.

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Aberrant activation of inflammasome system is evident in RTT.

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This new evidence can explain the demonstrated subclinical inflammation in RTT.

Baicalin attenuates lipopolysaccharide-induced neuroinflammation in cerebral cortex of mice via inhibiting nuclear factor kappa B (NF-κB) activation

Baicalin is a plant-derived flavonoid that has anti-inflammatory and anti-oxidative effects. We investigated an anti-inflammatory effect of baicalin against lipopolysaccharide (LPS)-induced damage in cerebral cortex. Adult mice were divided into control, LPS-treated, and LPS and baicalin co-treated animals. LPS (250 µg/kg/day) and baicalin (10 mg/kg/day) were intraperitoneally injected for 7 days. LPS treatment induced histopathological changes in cerebral cortex, whereas baicalin protected neuronal cells against LPS toxicity. Moreover, baicalin treatment attenuated LPS-induced increases of reactive oxygen species and oxidative stress in cerebral cortices. Ionized calcium binding adaptor molecule-1 (Iba-1) and glial fibrillary acidic protein (GFAP) are known as markers of activated microglia and astrocyte, respectively. Results of Western blot and immunofluorescence staining showed that LPS exposure induces increases of Iba-1 and GFAP expressions, whereas baicalin alleviates LPS-induced increases of these proteins. Baicalin also prevented LPS-induced increase of nuclear factor kappa B (NF-κB). LPS treatment led to increases of pro-inflammatory factors including interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α). Increases of these pro-inflammatory mediators were attenuated in baicalin co-treated animals. These results demonstrated that baicalin regulates neuroglia activation and modulates inflammatory factors in LPS-induced neuronal injury. Thus, our findings suggest that baicalin exerts a neuroinflammatory effect against LPS-induced toxicity through decreasing oxidative stress and inhibiting NF-κB mediated inflammatory factors, such as IL-1β and TNF-α.

Alkamides from Tropaeolum tuberosum inhibit inflammatory response induced by TNF-α and NF-κB

ETHNO-PHARMACOLOGICAL RELEVANCE

Tropaeolum tuberosum, commonly known as "Mashua", is one of the plants most frequently used by Andean (Peruvian-Bolivian) people as food and medicine. It is used as a remedy against a wide range of diseases, especially those related with inflammation.

OBJECTIVES

This study aims to identify compounds active against inflammatory related conditions.

MATERIALS AND METHODS

A bioassay-guided isolation of anti-inflammatory compounds from black and purple tubers of T. tuberosum was performed measuring TNF-α and NF-κB production in THP-1 monocytic cells.

RESULTS

The bioassay-guided isolation led to one active compound from purple T. tuberosum, N-oleoyldopamine (1), and another active compound from black T. tuberosum, N-(2-Hydroxyethyl)-7Z,10Z,13Z,16Z-docosatetraenamide (2). Both compounds displayed anti-TNF-α activity with IC₅₀ values of 3.12 ± 0.19 μM and 1.56 ± 0.15 μM, respectively. Also, both compounds suppressed NF-κB with IC₅₀ of 3.54 ± 0.02 μM and 1.77 ± 0.07 μM, respectively.

CONCLUSIONS

We identified bioactive compounds from purple and black Tropaeolum tuberosum responsible for their anti-inflammatory activity: N-oleoyldopamine (1) and N-(2-Hydroxyethyl)-7Z,10Z,13Z,16Z-docosatetraenamide (2). This is the first report which isolates these compounds from T. tuberosum and describes their anti-inflammatory activities.

Papaver nudicaule (Iceland poppy) alleviates lipopolysaccharide-induced inflammation through inactivating NF-κB and STAT3

BACKGROUND

Papaver nudicaule belongs to the Papaveraceae family, which is planted as an annual herbaceous species generally for ornamental purpose. Papaver rhoeas in the same family has been reported to have various pharmacological activities such as antioxidant and analgesic effects. In contrast, little is known about the pharmacological activity of Papaver nudicaule. In this study, the anti-inflammatory activity of Papaver nudicaule extracts and the action mechanisms were investigated in RAW264.7 macrophage cells.

METHODS

To investigate the anti-inflammatory activity of five cultivars of Papaver nudicaule with different flower color, samples were collected from their aerial parts at two growth stages (60 and 90 days) and their ethanol extracts were evaluated in the lipopolysaccharide (LPS)-treated RAW264.7 cells by measuring nitric oxide (NO) and prostaglandin E2 (PGE2) levels. Interleukin 1-beta (IL-1β), Interleukin-6 (IL-6) and Tumor necrosis factor alpha (TNF-α) production were also analyzed by RT-PCR and multiplex assays. Nuclear Factor-kappa-light-chain-enhancer of activated B cells (NF-κB) and Signal transducer and activator of transcription 3 (STAT3) signaling pathways were examined using western blotting and luciferase reporter assays to reveal the action mechanism of Papaver nudicaule extracts in their anti-inflammatory activity.

RESULTS

All of the Papaver nudicaule extracts were effective in reducing the LPS-induced NO, which is an important inflammatory mediator, and the extract of Papaver nudicaule with white flower collected at 90 days (NW90) was selected for further experiments because of the best effect on reducing the LPS-induced NO as well as no toxicity. NW90 lowered the LPS-induced PGE2 level and decreased the LPS-induced Nitric oxide synthase 2 (NOS2) and Cyclooxygenase 2 (COX2). In addition, NW90 reduced the LPS-induced inflammatory cytokines, IL-1β and IL-6. Furthermore, NW90 inhibited the LPS-induced activation of NF-κB and STAT3.

CONCLUSIONS

These results indicate that NW90 may restrain inflammation by inhibiting NF-κB and STAT3, suggesting the potential therapeutic properties of Papaver nudicaule against inflammatory disease.

Effects of 17β-Estradiol on Colonic Permeability and Inflammation in an Azoxymethane/Dextran Sulfate Sodium-Induced Colitis Mouse Model

Background/Aims

Intestinal barrier dysfunction is a hallmark of inflammatory bowel diseases (IBDs) such as ulcerative colitis. This dysfunction is caused by increased permeability and the loss of tight junctions in intestinal epithelial cells. The aim of this study was to investigate whether estradiol treatment reduces colonic permeability, tight junction disruption, and inflammation in an azoxymethane (AOM)/dextran sodium sulfate (DSS) colon cancer mouse model.

Methods

The effects of 17β-estradiol (E2) were evaluated in ICR male mice 4 weeks after AOM/DSS treatment. Histological damage was scored by hematoxylin and eosin staining and the levels of the colonic mucosal cytokine myeloperoxidase (MPO) were assessed by enzyme-linked immunosorbent assay (ELISA). To evaluate the effects of E2 on intestinal permeability, tight junctions, and inflammation, we performed quantitative real-time polymerase chain reaction and Western blot analysis. Furthermore, the expression levels of mucin 2 (MUC2) and mucin 4 (MUC4) were measured as target genes for intestinal permeability, whereas zonula occludens 1 (ZO-1), occludin (OCLN), and claudin 4 (CLDN4) served as target genes for the tight junctions.

Results

The colitis-mediated induced damage score and MPO activity were reduced by E2 treatment (p<0.05). In addition, the mRNA expression levels of intestinal barrier-related molecules (i.e., MUC2, ZO-1, OCLN, and CLDN4) were decreased by AOM/DSS-treatment; furthermore, this inhibition was rescued by E2 supplementation. The mRNA and protein expression of inflammation-related genes (i.e., KLF4, NF-κB, iNOS, and COX-2) was increased by AOM/DSS-treatment and ameliorated by E2.

Conclusions

E2 acts through the estrogen receptor β signaling pathway to elicit anti-inflammatory effects on intestinal barrier by inducing the expression of MUC2 and tight junction molecules and inhibiting pro-inflammatory cytokines.

Pharmacological inhibition of TLR4/NF-κB with TLR4-IN-C34 attenuated microcystin-leucine arginine toxicity in bovine Sertoli cells

This study investigated the pharmacological inhibition of the toll-like receptor 4 (TLR4) genes as a measure to attenuate microcystin-LR (MC-LR) reproductive toxicity. Bovine Sertoli cells were pretreated with TLR4-IN-C34 (C34) for 1 hour. Thereafter the pretreated and non-pretreated Sertoli cells were cultured in medium containing 10% heat-activated fetal bovine serum + 80 μg/L MC-LR for 24 hours to assess the ability of TLR4-IN-C34 to attenuate the toxic effects of MC-LR. The results showed that TLR4-IN-C34 inhibited MC-LR-induced mitochondria membrane damage, mitophagy and downregulation of blood-testis barrier constituent proteins via TLR4/nuclear factor-kappaB and mitochondria-mediated apoptosis signaling pathway blockage. The downregulation of the mitochondria electron transport chain, energy production and DNA replication related genes (mt-ND2, COX-1, COX-2, ACAT, mtTFA) and upregulation of inflammatory cytokines (interleukin [IL]-6, tumor necrosis factor-α, IL-1β, interferon-γ, IL-4, IL-10, IL-13 and transforming growth factor β1) were modulated by TLR4-IN-C34. Taken together, we conclude that TLR4-IN-C34 inhibits MC-LR-related disruption of mitochondria membrane, mitophagy and downregulation of blood-testis barrier proteins of the bovine Sertoli cell via cytochrome c release and TLR4 signaling blockage.

Effectiveness of denosumab on back pain-related disability and quality-of-life in patients with vertebral fragility fractures

Background: Denosumab is a fully human IgG2 monoclonal antibody that, neutralizing the receptor activator of nuclear factor kappa-Β ligand (RANKL), inhibits the osteoclast-mediated bone resorption. It is yet to be defined if denosumab can reduce osteoporosis-related disability and improve health-related quality-of-life (HRQoL) in patients with fragility fractures.Objective: To assess the effectiveness of denosumab in reducing back pain related disability and improving HRQoL in osteoporotic post-menopausal women with vertebral fractures.Research design and methods: A real practice prospective study was carried out, enrolling women over 50 years with a post-menopausal osteoporosis that experienced at least one vertebral fracture receiving subcutaneous denosumab (60 mg, every 6 months), calcium carbonate (500-1000 mg/day) and cholecalciferol (800 IU/day) for 1 year. Back pain related disability was assessed as the primary outcome using the Spine Pain Index (SPI); secondary outcomes were: SF-12 (Physical Health Composite Score, PCS, and Mental Health Composite Score, MCS), and EuroQol-5D (EuroQol-5D-3L index and EuroQol-Visual Analog Scale, EQ-VAS). All outcome measures were assessed at baseline (T0), after 6 months (T1), and after 12 months (T2) of treatment. Trabecular Bone Score (TBS), lumbar spine (LS) and femoral neck (FN) BMD at T0 and T2 were also evaluated.Results: This study included 140 post-menopausal women, mean age = 70.60 (SD = 8.81) years. There were statistically significant differences after 12 months (T2-T0) in all outcomes assessed: SPI (p < 0.001), SF-12 PCS (p < 0.001), SF-12 MCS (p < 0.001), EQ-5D-3L index (p = 0.039), and EQ-VAS (p = 0.003). Moreover, there was a significant improvement of both LS BMD (p < 0.001) and FN BMD (p < 0.001). No local or systemic adverse events, including new vertebral fractures, osteonecrosis of the jaw and atypical femur fractures, were reported.Conclusions: The data demonstrated that denosumab was effective in reducing back pain related disability and in improving HRQoL in post-menopausal women with vertebral fractures.

NFKB1 and MANBA Confer Disease Susceptibility to Primary Biliary Cholangitis via Independent Putative Primary Functional Variants

BACKGROUND & AIMS

Primary biliary cholangitis (PBC) is a chronic and cholestatic liver disease that eventually leads to cirrhosis and hepatic failure. We recently identified several susceptibility genes included NFKB1 and MANBA for PBC in the Japanese population by genome-wide association study. However, the primary functional variants in the NFKB1/MANBA region and the molecular mechanism for conferring disease susceptibility to PBC have not yet been clarified.

METHODS

We performed high-density association mapping based on a single-nucleotide polymorphism (SNP) imputation analysis, using data from a whole-genome sequence reference panel of 1070 Japanese individuals and the previous genome-wide association study (1389 PBC patients, 1508 healthy controls). Among SNPs (P < 5.0 × 10^-7) in the NFKB1/MANBA region, putative primary functional variants and the molecular mechanism for conferring disease susceptibility to PBC were identified by in silico/in vitro functional analysis.

RESULTS

Among the SNPs in the NFKB1/MANBA region, rs17032850 and rs227361, which changed the binding of transcription factors lymphoid enhancer-binding factor 1 (LEF-1) and retinoid X receptor α (RXRα), respectively, were identified as putative primary functional variants that regulate gene expression. In addition, expression-quantitative trait locus data and gene editing using a clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9 system supported the potential role of rs17032850 and rs227361 in regulating NFKB1 and MANBA expression, respectively.

CONCLUSIONS

We identified independent putative primary functional variants in NFKB1/MANBA and showed the distinct molecular mechanism by which each putative primary functional variant conferred susceptibility to PBC. Our approach was useful to dissect the pathogenesis not only of PBC, but also other digestive diseases in which NFKB1/MANBA has been reported as a susceptibility locus.

Th1-skewed profile and excessive production of proinflammatory cytokines in a NFKB1-deficient patient with CVID and severe gastrointestinal manifestations

Monoallelic loss-of-function mutations in NFKB1 were recently recognized as the most common monogenic cause of common variable immunodeficiency (CVID). The prototypic clinical phenotype of NFKB1-deficient patients includes common CVID features, such as hypogammaglobulinaemia and sinopulmonary infections, plus other highly variable individual manifestations. Here, we describe a patient with a profound CVID phenotype and severe gastrointestinal manifestations, including chronic and recurrent diarrhoea. Using an NGS customized panel of 323 genes related to primary immunodeficiencies, we identified a novel monoallelic loss-of-function mutation in NFKB1 leading to a truncated protein (c.1149delT/p.Gly384Glu ∗ 48). Interestingly, we also found a rare variant in NOD2 previously associated with Crohn's disease (p.His352Arg). Our patient had hypogammaglobulinaemia with a small number of B cells, most of which were naïve. The most noteworthy findings included marked skewing towards a Th1 phenotype in peripheral blood T cells and excessive production of proinflammatory cytokines (IL-1β, TNFα). The patient's 6-year-old daughter, a carrier of the NFKB1 mutation, is clinically asymptomatic, but has started to show cellular and molecular changes. This case of NFKB1 deficiency appears to be a combination of immunodeficiency and a hyperinflammatory state. The current situation of the patient's daughter provides a glimpse of the preclinical phase of the condition.

Association of TNFAIP3 and TNIP1 polymorphisms with systemic lupus erythematosus risk: A meta-analysis

OBJECT

With the development of GWAS, both TNFAIP3 and TNIP1 were revealed to be susceptibility genes of SLE. However, some other studies revealed no association between TNFAIP3, TNIP1 and SLE susceptibility. In order to estimate such association more precisely and systemically, a meta-analysis was conducted.

METHOD

Studies on the association between TNFAIP3 rs2230926, TNIP1 rs7708392 and SLE risk were carefully selected via searching 3 databases (Pubmed, Embase, and Web of Science). A fixed- or random-effect model was used according to the heterogeneity, and a subgroup analysis by ethnicity was also performed.

RESULTS

26 studies from 18 articles involving a total of 21,372 patients and 30,165 controls were analyzed for TNFAIP3 rs2230926. A significant association between the minor G allele of TNFAIP3 rs2230926 and SLE risk was found via a random-effect model (OR = 1.643, 95% CI = (1.462, 1.847), p < 0.01). In the subgroup analysis by ethnicity, significant correlations were also found in all Caucasians, Asians, and Africans (OR = 1.675, 95% CI = (1.353, 2.074), p < 0.01; OR = 1.738, 95% CI = (1.557, 1.940), p < 0.01; OR = 1.324, 95% CI = (1.029, 1.704), p < 0.05). As for TNIP1 rs7708392, 21 studies from 12 articles involving 24,716 cases and 32,200 controls were analyzed. A significant association of the minor C allele of TNIP1 rs7708392 and SLE risk was found via a random-effect model (OR = 1.247, 95% CI = (1.175, 1.323), p < 0.01). In the subgroup analysis by ethnicity, significant correlations were found in Caucasians, and Africans (OR = 1.317, 95% CI = (1.239, 1.401), p < 0.01; OR = 1.210, 95% CI = (1.108, 1.322), p < 0.01). However, there was no significant association in Asians (OR = 1.122, 95% CI = (0.953, 1.321), p > 0.05).

CONCLUSION

The minor G allele of TNFAIP3 rs2230926 was associated with increased risk of SLE in all Caucasians, Asians, and Africans. The minor C allele of TNIP1 rs7708392 was associated with the increased risk of SLE in Caucasians and Africans, while it was not associated with SLE susceptibility in Asians.

Rutin and rutin-conjugated gold nanoparticles ameliorate collagen-induced arthritis in rats through inhibition of NF-κB and iNOS activation

Numerous studies have suggested that nuclear factor-κB (NF-κB) and inducible nitric oxide synthase (iNOS) are important mediators of inflammatory response in human and animal models of arthritis. Besides, oxidative stress markers, nitric oxide (NO) and peroxide (PO) are also major contributors in the pathogenesis of rheumatoid arthritis (RA). Over expression of these inflammatory mediators leads to the extracellular matrix degradation, and excessive cartilage and bone resorption, ultimately leading to the irreversible damage to joints. The aim of the present study was to investigate the anti-arthritic mechanism of bioflavonoids, rutin and rutin-conjugated gold nanoparticles (R-AuNPs) by determining their role in the modulation of NF-κB and iNOS expression in collagen-induced arthritis (CIA) model of rats. Arthritis was induced by the subcutaneous administration of bovine type II collagen. Treatment was started with rutin, indomethacin + rutin (I + R) and R-AuNPs on the day of CIA induction. The severity of arthritis was determined by measuring the arthritic score on alternate days until mean arthritic score of 4 was observed. The NO and PO levels were also analyzed in serum samples. NF-κB and iNOS expression levels were determined in spleen tissue samples by real time RT-PCR and immunohistochemistry. Marked reduction in the arthritic score as well as in the NO and PO levels was observed in the treated groups. A significant downregulation in the NF-κB and iNOS expression levels was also observed in the treatment groups compared to the arthritic control group. Collectively, the findings suggest potential clinical role of rutin and R-AuNPs in the treatment of rheumatoid arthritis.

NF-κB signaling in inflammation

The transcription factor NF-κB regulates multiple aspects of innate and adaptive immune functions and serves as a pivotal mediator of inflammatory responses. NF-κB induces the expression of various pro-inflammatory genes, including those encoding cytokines and chemokines, and also participates in inflammasome regulation. In addition, NF-κB plays a critical role in regulating the survival, activation and differentiation of innate immune cells and inflammatory T cells. Consequently, deregulated NF-κB activation contributes to the pathogenic processes of various inflammatory diseases. In this review, we will discuss the activation and function of NF-κB in association with inflammatory diseases and highlight the development of therapeutic strategies based on NF-κB inhibition.

Impact of loss of NF-κB1, NF-κB2 or c-REL on SLE-like autoimmune disease and lymphadenopathy in Fas(lpr/lpr) mutant mice

Defects in apoptosis can cause autoimmune disease. Loss-of-function mutations in the 'death receptor' FAS impair the deletion of autoreactive lymphocytes in the periphery, leading to progressive lymphadenopathy and systemic lupus erythematosus-like autoimmune disease in mice (Fas(lpr/lpr) (mice homozygous for the lymphoproliferation inducing spontaneous mutation)) and humans. The REL/nuclear factor-κB (NF-κB) transcription factors regulate a broad range of immune effector functions and are also implicated in various autoimmune diseases. We generated compound mutant mice to investigate the individual functions of the NF-κB family members NF-κB1, NF-κB2 and c-REL in the various autoimmune pathologies of Fas(lpr/lpr) mutant mice. We show that loss of each of these transcription factors resulted in amelioration of many classical features of autoimmune disease, including hypergammaglobulinaemia, anti-nuclear autoantibodies and autoantibodies against tissue-specific antigens. Remarkably, only c-REL deficiency substantially reduced immune complex-mediated glomerulonephritis and extended the lifespan of Fas(lpr/lpr) mice. Interestingly, compared with the Fas(lpr/lpr) animals, Fas(lpr/lpr)nfkb2(-/-) mice presented with a dramatic acceleration and augmentation of lymphadenopathy that was accompanied by severe lung pathology due to extensive lymphocytic infiltration. The Fas(lpr/lpr)nfkb1(-/-) mice exhibited the combined pathologies caused by defects in FAS-mediated apoptosis and premature ageing due to loss of NF-κB1. These findings demonstrate that different NF-κB family members exert distinct roles in the development of the diverse autoimmune and lymphoproliferative pathologies that arise in Fas(lpr/lpr) mice, and suggest that pharmacological targeting of c-REL should be considered as a strategy for therapeutic intervention in autoimmune diseases.

Caffeic acid phenethyl ester lessens disease symptoms in an experimental autoimmune uveoretinitis mouse model

Experimental autoimmune uveoretinitis (EAU) is an autoimmune disease that models human uveitis. Caffeic acid phenethyl ester (CAPE), a phenolic compound isolated from propolis, possesses anti-inflammatory and immunomodulatory properties. CAPE demonstrates therapeutic potential in several animal disease models through its ability to inhibit NF-κB activity. To evaluate these therapeutic effects in EAU, we administered CAPE in a model of EAU that develops after immunization with interphotoreceptor retinal-binding protein (IRBP) in B10.RIII and C57BL/6 mice. Importantly, we found that CAPE lessened the severity of EAU symptoms in both mouse strains. Notably, treated mice exhibited a decrease in the ocular infiltration of immune cell populations into the retina; reduced TNF-α, IL-6, and IFN-γ serum levels: and inhibited TNF-α mRNA expression in retinal tissues. Although CAPE failed to inhibit IRBP-specific T cell proliferation, it was sufficient to suppress cytokine, chemokine, and IRBP-specific antibody production. In addition, retinal tissues isolated from CAPE-treated EAU mice revealed a decrease in NF-κB p65 and phospho-IκBα. The data identify CAPE as a potential therapeutic agent for autoimmune uveitis that acts by inhibiting cellular infiltration into the retina, reducing the levels of pro-inflammatory cytokines, chemokine, and IRBP-specific antibody and blocking NF-κB pathway activation.

CXCR4 expression on pathogenic T cells facilitates their bone marrow infiltration in a mouse model of aplastic anemia

Aplastic anemia (AA) is a disease characterized by T-cell-mediated destruction of bone marrow (BM) hematopoietic stem and progenitor cells. Physiologically, T cells migrate to the BM in response to chemokines, such as SDF-1α, the ligand for CXCR4. However, how T cells traffic to the BM in AA is poorly understood. CXCR4 is aberrantly expressed in immune-mediated diseases and its regulation by nuclear factor-κB (NF-κB) in cancer models is well documented. In this study, we show that CXCR4 is highly expressed on BM-infiltrating CD4(+) and CD8(+) T cells in a mouse model of AA. Inhibiting CXCR4 in AA mice, using CXCR4(-/-) splenocytes or AMD3100, significantly reduced BM infiltration of T cells. We also report that NF-κB occupancy at the CXCR4 promoter is enhanced in BM-infiltrating CD8(+) T cells of AA mice. Moreover, inhibiting NF-κB signaling in AA mice using Bay11 or dehydroxymethylepoxyquinomicin, or transferring p50(-/-) splenocytes, decreased CXCR4 expression on CD8(+) T cells, significantly reduced BM infiltration of T cells, and strongly attenuated disease symptoms. Remarkably, therapeutic administration of Bay11 significantly extended survival of AA mice. Overall, we demonstrate that CXCR4 mediates migration of pathogenic T cells to the BM in AA mice, and inhibiting NF-κB signaling may represent a novel therapeutic approach to treating AA.

Loss of c-REL but not NF-κB2 prevents autoimmune disease driven by FasL mutation

FASL/FAS signaling imposes a critical barrier against autoimmune disease and lymphadenopathy. Mutant mice unable to produce membrane-bound FASL (FasL(Δm/Δm)), a prerequisite for FAS-induced apoptosis, develop lymphadenopathy and systemic autoimmune disease with immune complex-mediated glomerulonephritis. Prior to disease onset, FasL(Δm/Δm) mice contain abnormally high numbers of leukocytes displaying activated and elevated NF-κB-regulated cytokine levels, indicating that NF-κB-dependent inflammation may be a key pathological driver in this multifaceted autoimmune disease. We tested this hypothesis by genetically impairing canonical or non-canonical NF-κB signaling in FasL(Δm/Δm) mice by deleting the c-Rel or NF-κB2 genes, respectively. Although the loss of NF-κB2 reduced the levels of inflammatory cytokines and autoantibodies, the impact on animal survival was minor due to substantially accelerated and exacerbated lymphoproliferative disease. In contrast, a marked increase in lifespan resulting from the loss of c-REL coincided with a striking reduction in classical parameters of autoimmune pathology, including the levels of cytokines and antinuclear autoantibodies. Notably, the decrease in regulatory T-cell numbers associated with loss of c-REL did not exacerbate autoimmunity in FasL(Δm/Δm)c-rel(-/-) mice. These findings indicate that selective inhibition of c-REL may be an attractive strategy for the treatment of autoimmune pathologies driven by defects in FASL/FAS signaling that would be expected to circumvent many of the complications caused by pan-NF-κB inhibition.

Sesquiterpene lactones and their derivatives inhibit high glucose-induced NF-κB activation and MCP-1 and TGF-β1 expression in rat mesangial cells

Diabetic nephropathy (DN) is one of the most common and serious chronic complications of diabetes mellitus, however, no efficient clinical drugs exist for the treatment of DN. We selected and synthesized several sesquiterpene lactones (SLs), and then used the MTT assay to detect rat mesangial cells (MCs) proliferation, ELISA to measure the expression level of monocyte chemoattractant protein-1 (MCP-1), transforming growth factor beta (TGF-β1) and fibronectin(FN), real-time fluorescent quantitative PCR analysis to measure the MCP-1 and TGF-β1 gene expression, western blot to detect the level of IκBα protein and EMSA to measure the activation of nuclear factor kappa B (NF-κB). We discovered that SLs, including parthenolide (PTL), micheliolide (MCL), arglabin, and isoalantolactone (IAL), as well as several synthetic analogs of these molecules, could effectively attenuate the high glucose-stimulated activation of NF-κB, the degradation of IκBα, and the expression of MCP-1, TGF-β1 and FN in rat mesangial cells (MCs). These findings suggest that SLs and their derivatives have potential as candidate drugs for the treatment of DN.

Regulation of nuclear factor-κB in autoimmunity

Nuclear factor (NF)-κB transcription factors are pivotal regulators of innate and adaptive immune responses, and perturbations of NF-κB signaling contribute to the pathogenesis of immunological disorders. NF-κB is a well-known proinflammatory mediator, and its deregulated activation is associated with the chronic inflammation of autoimmune diseases. Paradoxically, NF-κB plays a crucial role in the establishment of immune tolerance, including both central tolerance and the peripheral function of regulatory T (Treg) cells. Thus, defective or deregulated activation of NF-κB may contribute to autoimmunity and inflammation, highlighting the importance of tightly controlled NF-κB signaling. This review focuses on recent progress regarding NF-κB regulation and its association with autoimmunity.

Cyclosporine in anti-Jo1-positive patients with corticosteroid-refractory interstitial lung disease

OBJECTIVE

To describe the longterm effectiveness and safety of cyclosporine (CYC) in patients with anti-Jo1-positive antisynthetase syndrome with corticosteroid-refractory interstitial lung disease (ILD).

METHODS

All patients with anti-Jo1 antisynthetase syndrome referred to our division between June 1991 and February 2010 were retrospectively evaluated for ILD. ILD was assessed using pulmonary function tests (PFT) and/or high-resolution computed tomography (HRCT). Kazerooni score was used to evaluate the HRCT extent of ILD. Prednisone was the first-line treatment in all cases (1 mg/kg/day orally, then tapering). Patients with corticosteroid-refractory or relapsing ILD were then included in this retrospective study. All patients started CYC (3 mg/kg/day) without increasing prednisone dosage. Both PFT and chest HRCT were regularly reassessed during followup.

RESULTS

Over the period of study we evaluated 18 patients with antisynthetase syndrome; 17 had ILD (13 women; median age at ILD onset 57 yrs); all patients failed prednisone within 12 months of ILD onset and subsequently started CYC. The median followup on CYC was 96 months [interquartile range (IQR) 57-120 mo]. Upon starting CYC, median forced vital capacity (FVC) was 60% (IQR 56%-70%), median DLCO 60% (IQR 50%-62.75%), and median Kazerooni score 16 (IQR 7-18). After 1 year of CYC, FVC (p = 0.0006), DLCO (p = 0.0010), and total Kazerooni score (p = 0.0002) improved and prednisone was tapered (median reduced from 25 mg/day to 2.5 mg/day; p < 0.0001). The results were substantially maintained including at last available followup. CYC side effects were hypertension (5 patients) and creatinine increase (6 patients). CYC was reduced in 3 cases and withdrawn in 4. Three out of 4 patients who interrupted CYC experienced ILD relapse; 2 patients recommenced low-dose CYC with subsequent ILD control. One patient refused re-treatment and subsequently died.

CONCLUSION

CYC is effective and substantially safe in patients with anti-Jo1 antisynthetase syndrome with corticosteroid-refractory ILD. CYC withdrawal may be associated with ILD relapse, and low-dose CYC was effective in ILD control.

Reproductive immunology: current status and future directions (part I)

Extensive research work over the past couple of decades has indicated a series of intricate relations between immune and reproductive systems. A range of reproductive immunology topics including the roles of adoptive and innate immunity in infertility and pregnancy, the immune system's role in induction of labor and preterm delivery, and immuno-modulatory effects of the female sex hormones will be discussed in this and the next issue of the Journal. The implications of this research on the development of novel therapeutic approaches are also addressed.