Helminth products as a potential therapeutic strategy for inflammatory diseases

Helminths secrete several molecules that can modulate the immune responses, favoring their evasion and perpetuate their survival in the host. These molecules interfere with antigen presentation, cell proliferation and activation, antibody production, cause cell death, and stimulate regulatory responses. Here, we focus on some helminth products and address their immunomodulatory effects in the host immune system and, also, we describe some anti-inflammatory properties of an Ascaris suum-derived immunomodulatory molecule, named PAS-1. This protein is a 200-kDa molecule isolated by affinity chromatography using MAIP-1 (monoclonal antibody which recognizes PAS-1), coupled to Sepharose 4B. It suppresses the inflammatory responses in murine models of delayed-type hypersensitivity, lung allergic inflammation and LPS-induced inflammation into air pouches. PAS-1 also stimulates the secretion of regulatory cytokines such as IL-10 and TGF-beta and primes IFN-gamma-secreting CD8+ and IL-10/ TGF-beta-secreting CD4+CD25+ cell clones that avoid the lung inflammation. Thus, this protein is a potent immunomodulatory component that may be used for therapeutic interventions in inflammatory diseases.     

IL-6 and arthritis: a detrimental or beneficial mediator?

Acute inflammation is accompanied by changes in the concentrations of several plasma proteins. Cytokines play a crucial role in the regulation of inflammatory events. Inflammatory disorders such as rheumatoid arthritis are characterized by an overproduction of several cytokines including interleukin-6 (IL-6). Recent data suggest that IL-6 and other members of the IL-6-cytokine family have anti-inflammatory and immunosuppressive properties, and therefore may negatively regulate inflammatory processes.     

Effects of physical exercise on inflammatory markers of atherosclerosis

It is well established that physically fit individuals have a reduced risk of developing CVD (cardiovascular disease) and other age-related chronic disorders. Regular exercise is an established therapeutic intervention with an enormous range of benefits. Chronic low-grade systemic inflammation may be involved in atherosclerosis, diabetes and in pathogenesis of several chronic pathological conditions; recent findings confirm that physical activity induces an increase in the systemic levels of a number of cytokines and chemokines with anti-inflammatory properties. The possibility that regular physical exercise exerts anti-inflammation activity, being the interaction between contracting muscle and the other tissues and the circulating cells mediated through signals transmitted by "myokines" produced with muscle contractions. To date the list of myokines includes IL-6, IL-8, and IL-15. During muscle contractions are also released IL- 1receptor antagonis and sTNF-R, molecules that contribute to provide anti-inflammatory actions. Nevertheless discrepancies, analysis of available researches seem to confirm the efficacy of regular physical training as a nonpharmacological therapy having target chronic low-grade inflammation. Given this, physical exercise could be considerate a useful weapon against local vascular and systemic inflammation in atherosclerosis. Several mechanisms explain the positive effect of chronic exercise, nevertheless, these mechanisms do not fully enlighten all pathways by which exercise can decrease inflammation and endothelial dysfunction, and hence modulate the progression of the underlying disease progress.     

Lung fibrosis induced by crystalline silica particles is uncoupled from lung inflammation in NMRI mice

Previous studies in rats have suggested a causal relationship between progressive pulmonary inflammation and lung fibrosis induced by crystalline silica particles. We report here that, in NMRI mice, the lung response to silica particles is accompanied by a mild and non progressive pulmonary inflammation which is dispensable for the development of lung fibrosis. We found that glucocorticoid (dexamethasone) dramatically reduced lung injury, cellular inflammation and pro-inflammatory cytokine expression (TNF-α, IL-1β and KC) but had no significant effect on silica-induced lung fibrosis and expression of the fibrogenic and suppressive cytokines TGF-β and IL-10 in mice. Other anti-inflammatory molecules such as the COX inhibitor piroxicam or the phosphodiesterase 5 inhibitor sildenafil also reduced lung inflammation without modifying collagen, TGF-β or IL-10 lung content. Our findings indicate that the development of lung fibrosis in silica-treated NMRI mice is not driven by inflammatory lung responses and suggest that suppressive cytokines may represent critical fibrotic factors and potential therapeutic targets in silicosis.     

Preliminary exploration on anti-inflammatory mechanism of Corilagin (beta-1-O-galloyl-3,6-(R)-hexahydroxydiphenoyl-D-glucose) in vitro

Corilagin (beta-1-O-galloyl-3,6-(R)-hexahydroxydiphenoyl-D-glucose) is a novel member of the tannin family which has been discovered from many medicinal plants and has been confirmed in many pharmacological activities. However, the purified Corilagin that was used in experiment is rare, and the anti-inflammatory mechanism of Corilagin has not been investigated clearly. This study is to explore the inner anti-inflammatory mechanism of Corilagin. Inflammatory cellular model was established by lipopolysaccharide (LPS) interfering on RAW264.7 cell line. Levels of TNF-alpha, IL-1beta, IL-6, NO and IL-10 in supernatant, mRNA expression of TNF-alpha, COX-2, iNOS and HO-1, protein expression of COX-2 and HO-1, translocation of NF-kappaB were assayed by ELISA or Griess method, real-time quantitative PCR, western blot and immunocytochemistry method, respectively. As a result, Corilagin could significantly reduce production of pro-inflammatory cytokines and mediators TNF-alpha, IL-1beta, IL-6, NO (iNOS) and COX-2 on both protein and gene level by blocking NF-kappaB nuclear translocation. Meanwhile Corilagin could notably promote release of anti-inflammatory factor HO-1 on both protein and gene level, but suppress the release of IL-10. In conclusion, the anti-inflammatory effects of Corilagin are attributed to the suppression of pro-inflammatory cytokines and mediators by blocking NF-kappaB activation. Corilagin also can promote HO-1 production to induce regression of inflammation but can inhibit IL-10 production like Dexamethasone. Corilagin possesses a potential anti-inflammatory effect by not only abating inflammatory impairment but also promoting regression of inflammation and has a good prospect to be used in many inflammation-related diseases.     

Inflammation is regulated by the adenosine derivative molecule,IFC-305, during reversion of cirrhosis in a CCl4 rat model

Cirrhosis is a liver pathology originated by hepatocytes, Kupffer and hepatic stellate cells interactions and transformations. This pathology is associated with inflammation and fibrosis, originated by molecular signals secreted by immunological and parenchymal cells, such as cytokines and chemokines, like IL-1β, IL-6, TNF-α or MCP-1, driven by Kupffer cells signals. As part of inflammation resolution, the same activated Kupffer cells contribute to anti-inflammatory effects with IL-10 and MMP-9 secretion. In a Wistar rat model, cirrhosis induced with CCl₄ is characterized by increased inflammatory cytokines, IL-6, IL-1β, MCP-1, and TNF-α, in plasma and liver tissue. The IFC-305 compound, an adenosine derivative salt, reverses the cirrhosis in this model, suggesting that immune mechanisms related to inflammation should be explored. The IFC-305 reduced inflammatory cytokines, supporting the anti-inflammatory effects induced by the elevation of IL-10, as well as the reduction of M1 inflammatory macrophages (CD11b/c⁺/CD163⁺) and the increase of M2 anti-inflammatory macrophages (HIS36⁺/CD11b⁺), measured by flow cytometry. Furthermore, the IFC-305 enhances the metabolic activity of arginase and moderates the inducible nitric oxide synthetase, evaluated through biochemical and immunohistochemical methods. These results contribute to understand the function of the IFC-305, which modulates the immune response in the Wistar rat model of CCl₄-induced cirrhosis and support the hepatic protective action through an anti-inflammatory effect, mainly mediated by Kupffer cells.     

Harnessing CD36 to rein in inflammation

Maintaining health requires a dynamic balance between the influence of pro-inflammatory and anti-inflammatory mediators. While inflammation serves an important protective role against infection, unrestrained inflammation is acutely lethal and unresolved inflammation contributes to a broad range of chronic disorders. Immunotherapy with cytokines themselves or cytokine antagonists faces strict limitations due to efficacy, safety and cost. More successful treatment of the pro-inflammatory component of chronic disorders may emerge from strategies designed to reset the balance between pro and anti-inflammatory cytokines through physiological regulatory pathways. One emerging avenue for this approach is exploitation of the link between the cell surface protein CD36 and the anti-inflammatory cytokine interleukin-10 (IL-10). Agents that increase CD36 expression and agents that directly bind to CD36 have anti-inflammatory properties that may directly relate to induction of IL-10. The immunosuppressive effects of apoptotic cells were first reported more than a decade ago and have since been tested in animal models and several clinical trials. A recent publication demonstrates that induction of IL-10 by apoptotic cells is largely dependent upon the interaction between apoptotic cells and CD36, the receptor on monocytes and macrophages for apoptotic cells. This provides a direct mechanistic link between CD36 engagement and IL-10 induction, opening up new possibilities for using CD36 ligands, agents that increase CD36 expression or a combination of both to modulate inflammation and treat, or even prevent, an important set of chronic disorders.     

白细胞介素-37的抑炎机制及其在疾病中的作用

IL-37属于细胞因子IL-1家族，有IL-37a－IL-37e共5种不同的亚型。近年来研究发现，IL-37是一种抑制炎症的双功能细胞因子，既可以直接在细胞内进入细胞核发挥作用，也可以分泌至细胞外，作用于自身或周围细胞的膜受体。此文就IL-37的主要生物学活性及其抑制炎症的相应机制，以及IL-37在临床上的应用研究进行综述，以期为临床抑炎治疗提供新思路和新靶点。     

Cholesterol, cytokines and diseases

A high level of cholesterol is associated with obesity, cardiovascular diseases and atherosclerosis. Immune response in atherosclerosis is mediated by chemokines which attract monocytes, leading to the innate immune response characterised by the production of cytokines. The immunoregulatory cytokines are an important bridge between innate and adductive immunity. TH1 cytokines are involved as effector T cells in inflammatory response, while TH2 cytokines can be anti-inflammatory such as IL-10 and IL-4. It is well known that statins enhance the production of TH2 cytokines whereas the secretion of TH1 cytokines is suppressed. For this purpose, we studied the significance of anti-inflammatory effect and suppression of inflammation by statins. In this paper we revisited the role of cholesterol and cytokines IL-18, IL-10, IL-12, TNF-α, interferon-γ, and chemokines in inflammatory diseases.     

Acanthoic acid inhibits LPS-induced inflammatory response by activating LXRα in human umbilical vein endothelial cells

Acanthoic acid, a pimaradiene diterpene isolated from Acanthopanax koreanum, has been reported to have anti-inflammatory activities. However, the effect of acanthoic acid on vascular inflammation has not been investigated. The aim of this study was to investigate the anti-inflammatory effects of acanthoic acid on lipopolysaccharide (LPS)-induced inflammatory response in human umbilical vein endothelial cells (HUVECs). The production of cytokines TNF-α and IL-8 was detected by ELISA. The expression of VCAM-1, ICAM-1, E-selectin, NF-κB and LXRα were detected by Western blotting. Adhesion of monocytes to HUVECs was detected by monocytic cell adhesion assay. The results showed that acanthoic acid dose-dependently inhibited LPS-induced TNF-α and IL-8 production. Acanthoic acid also inhibited TNF-α-induced IL-8 and IL-6 production. LPS-induced endothelial cell adhesion molecules, VCAM-1 and ICAM-1 were also inhibited by acanthoic acid. Acanthoic acid inhibited LPS-induced NF-κB activation. Furthermore, acanthoic acid dose-dependently up-regulated the expression of LXRα. In addition, our results showed that the anti-inflammatory effect of acanthoic acid was attenuated by transfection with LXRα siRNA. In conclusion, the anti-inflammatory effect of acanthoic acid is due to its ability to activate LXRα. Acanthoic acid may be a therapeutic agent for inflammatory cardiovascular disease.     

Anti-inflammatory properties of pro-inflammatory interferon-gamma

Production of interferon-gamma (IFNgamma) in response to infection is a hallmark of innate and adaptive immunity. In addition to the pivotal role of IFNgamma in host defense, its excessive release has been associated with the pathogenesis of chronic inflammatory and autoimmune diseases. In fact, knockout models reveal that IFNgamma plays a key role in mediating a number of pathological processes related to chronic immune activation. On the other hand, evidence has been accumulated in recent years that supports the concept of a dual role of IFNgamma in inflammation. Here, we review anti-inflammatory aspects of IFNgamma in the regulatory network of cytokine biology. These include induction of anti-inflammatory molecules such as interleukin (IL)-1 receptor antagonist (IL-1Ra) and IL-18 binding protein (IL-18BP), modulation of pro-inflammatory cytokine production, activation of apoptosis, and interference with the signal transduction machinery by induction of suppressors of cytokine signaling (SOCS).     

Intravenous administration of recombinant human IL-10 suppresses the development of anti-thy 1-induced glomerulosclerosis in rats

Aim: Interleukin-10 (IL-10) is a cytokine with potent antifibrotic and anti-inflammatory properties. However, IL-10 has a very short plasma half-life in vivo. This prompted the question whether a short intravenous treatment might have prolonged effects on more chronic processes like sclerosis. Methods: Glomerulosclerosis was induced by anti-Thymocyte 1 (Anti-Thy 1) antibody. Four days after induction, an intravenous injection of recombinant human IL-10 (rhIL-10) was given for 3 consecutive days. Untreated rats received vehicle only (phosphate-buffered saline). Parameters of inflammation and fibrosis were assessed at protein and mRNA levels. Untreated rats showed renal histopathological changes as compared to normal rats. Results: Glomerular matrix expansion and inflammatory cell influx was observed and an increase in glomerular-inducible nitric oxide synthetase and α-smooth muscle actin (α-SMA) were found on the protein level, factors that were clearly attenuated by IL-10 treatment. In particular, the decrease of matrix metalloproteinase-13 levels between days 4 and 7 was completely prevented by IL-10. In contrast, IL-10 did not significantly reduce mRNA levels for procollagen α1(1), α-SMA, and transforming growth factor 1. Conclusion: A short-term treatment with rhIL-10 after induction of Anti-Thy 1 antibody nephritic rats attenuated intraglomerular inflammation, and at the protein level also influenced the parameters reflecting matrix deposition and degradation. Despite in fact that IL-10 was shown to be effective in the inhibition of matrix deposition, it had no beneficial effect on proteinuria. LAY ABSTRACT: Interleukin-10 is a cytokine with potent antifibrotic and anti-inflammatory properties. Its short plasma half-life raises the question whether a short intravenous treatment might have prolonged effects on chronic disease like sclerosis. To confirm this, recombinant human interleukin-10 was used to treat glomerulosclerosis in rats. The disease was induced by Anti-Thy 1 antibody. Four days after induction, an intravenous injection of IL-10 was given for 3 consecutive days. Untreated rats received vehicle only (phosphate-buffered saline). Parameters of inflammation and fibrosis were assessed at protein and mRNA levels. In this study, untreated rats showed renal histopathological changes as compared to normal rats. Glomerular matrix expansion and inflammatory cell influx was observed, and increases in glomerular nitric oxide synthetase and α-smooth muscle actin α-SMA were found on the protein level. In contrast, treated rats clearly showed reduction of all these parameters. In particular, the decrease of anti-matrix metalloproteinase-13 (MMP-13) levels between days 4 and 7 was completely prevented by IL-10. However, IL-10 did not significantly reduce mRNA levels for procollagen α1(1), α-SMA, and TGFβ-1. Based on these results, it can be concluded that a short-term treatment with rhIL-10 after induction of Anti-Thy 1 antibody in nephritic rats attenuated intraglomerular inflammation, and at the protein level also influenced the parameters reflecting matrix deposition and degradation. Despite in fact that IL-10 was shown to be effective in the inhibition of matrix deposition, it had no beneficial effect on proteinuria.     

Reduced production of anti-inflammatory soluble HLA-G molecules in styrene exposed workers

HLA-G antigens are non-classical HLA-class I anti-inflammatory molecules. Since styrene exposure has been suggested to induce immune alteration, we analyzed plasma levels and "in vitro" peripheral blood mononuclear cell (PBMC) production of soluble HLA-G (sHLA-G) and interleukin-10 (IL-10) molecules after lipopolysaccharide (LPS) stimulation, in styrene exposed workers and healthy subjects. Exposed workers showed reduced plasma levels of sHLA-G and IL-10 in comparison to healthy controls. Similarly, lower levels of sHLA-G and IL-10 molecules were observed in PBMC culture supernatants after LPS activation. These data propose styrene exposure as a mediator of impaired sHLA-G production.     

Lebrikizumab for the treatment of asthma

Introduction: In asthma, most commonly, ‘conventional’ anti-inflammatory medications represented by inhaled corticosteroids and leukotriene inhibitors are effective. In some patients however additional inhibition of the airways inflammation is necessary. Such compounds might be molecules inhibiting specifically certain inflammation pathways and lebrikizumab an anti IL-13 molecule might represent a relevant example as a potential asthma therapy.

Areas covered: Discussion of the rationale for the use of lebrikizumab in asthma. Analysis of the related preclinical and clinical data on lebrikizumab in asthma.

Expert opinion: Lebrikizumab demonstrated efficacy in an asthma subset characterized by high serum periostin levels and by heavy eosinophilic inflammation. Phase III data are necessary in order to better position this therapy in asthma including as a potential personalized approach.     

Wound healing activity of carbon monoxide liberated from CO-releasing molecule (CO-RM)

Wound microenvironment presents widespread oxidant stress, inflammation, and onslaught of apoptosis. Carbon monoxide (CO) exerts pleiotropic cellular effects by modulating intracellular signaling pathways which translate into cellular protection against oxidative stress, inflammation, and apoptosis. CO-releasing molecules (CO-RMs) deliver CO in a controlled manner without altering carboxyhemoglobin levels. This study observed a potential therapeutic value of CO in the wound healing by using tricarbonyldichlororuthenium (II) dimer (CO-releasing molecule (CO-RM)-2), as one of the novel CO-releasing agent. The effect of CO-RM-2 treatment was studied on wound contraction, glucosamine, hydroxyproline levels, and mRNA of cytokines/adhesion molecule in rats using a full-thickness cutaneous wound model and angiogenesis in chick chorioallantoic membrane (CAM) model. CO-RM-2 treatment increased cellular proliferation and collagen synthesis as evidenced by the increase in wound contraction and hydroxyproline and glucosamine contents. The mRNA expression of cytokines endorsed fast healing, as was indicated by the inhibition of pro-inflammatory adhesion molecules such as ICAM-1 and cytokine TNF-α and upregulation of anti-inflammatory cytokine IL-10. An ELISA assay of IL-10 and TNF-α cytokines revealed pro-healing modulation in excision wound by CO-RM-2 treatment. CO-RM significantly promoted the angiogenesis as compared to the iCO-RM group in vitro in CAM model demonstrating pro-angiogenic effects of CO-RM-2 in wound healing process. These results indicate that CO-RM-2 may have a potential application in the management of recalcitrant/obstinate wounds wherein, active wound healing is desired. This study also opens up a new area of research for the synthesis of novel CO-releasing molecules to be used for such purposes.     

Anti-inflammatory and antinociceptive activities of indole-imidazolidine derivatives

Non-steroidal anti-inflammatory drugs (NSAIDs) represent a group of approximately 50 different medicines that are widely prescribed for the management of inflammation and that exhibit variable anti-inflammatory, anti-pyretic and analgesic activities. Most NSAIDs also exhibit a shared set of adverse effects, particularly related to gastrointestinal complications; thus, the development of new drugs for the treatment of chronic inflammation and pain continues to be an issue of high interest. Hydantoin and indole derivatives are reported to possess various pharmacological effects, including anti-inflammatory and analgesic activities. Therefore, the aim of this study was to evaluate the potential anti-inflammatory and antinociceptive activities of hybrid molecules containing imidazole and indole nuclei. The anti-inflammatory activities of 5-(1H-Indol-3-yl-methylene)-2-thioxo-imidazolidin-4-one (LPSF/NN-56) and 3-(4-Bromo-benzyl)-5-(1H-indol-3-yl-methylene)-2thioxo-imidazolidin-4-one (LPSF/NN-52) were evaluated using air pouch and carrageenan-induced peritonitis models as well as an acetic acid-induced vascular permeability model followed by IL-1β and TNF-α quantification. To evaluate the antinociceptive activities of the compounds, acetic acid-induced nociception, formalin and hot plate tests were also performed. The anti-inflammatory activities of the compounds were evidenced by a reduction in both leukocyte migration and the release of TNF-α and IL-1β in air pouch and peritonitis models. Upon acetic acid-induced nociception, a decrease in the level of abdominal writhing in the groups treated with LPSF/NN-52 (52.1%) or LPSF/NN-56 (63.1%) was observed. However, in the hot plate test, none of the derivatives tested exhibited an inhibition of nociception. These results indicate that the compounds tested exhibited promising anti-inflammatory and antinociceptive activities that likely involved the modulation of the immune system.     

Inflammatory mediators as potential therapeutic targets in the spine

Inflammation plays a variable part in the pathogenesis of several spinal disorders. Ankylosing spondylitis is a chronic inflammatory arthropathy of the spine and rheumatoid arthritis, whilst affecting predominantly limb joints, also affects the cervical spine in a significant proportion of people. Inflammation is also involved in disorders such as disc herniation and sciatica, which have previously been thought of as being primarily mechanical or degenerative. Anti-inflammatory agents which have been shown to be effective elsewhere in the body are discussed in this review as possible therapeutic agents in the spine. As the inflammatory cascade and immunopathology of these conditions continue to be elucidated, it has become apparent that individual molecules may be potential targets for inactivation or down-regulation. Candidates include pro-inflammatory cytokines, such as TNF-alpha, cytokines, e.g. IL-1 and IL-15, or enzymes enhancing the inflammation pathway such as the cyclooxygenases. Hence treatments based on inactivation of these molecules by various mechanisms, including antibodies, receptor antagonists, enzyme inhibitors or gene therapy, are being introduced. However, the mode of action of a particular molecule can be complex and sometimes apparently contradictory. For example, TNF-alpha is known to play an important role in promoting inflammation by upregulating expression of cell adhesion molecules on endothelial cells and stimulating the production of reactive oxygen intermediates, nitric oxide and prostaglandins. However, it can also have an immunosuppressive and anti-inflammatory role after prolonged release. Therefore, although inhibitors of many of these molecules are now in clinical application and trials (many with promising results in rheumatoid arthritis), it is important to remain vigilant and monitor long-term outcomes particularly when these treatments are used in clinical syndromes with relatively poorly defined immunopathology such as spinal disorders.     

The role of inflammation in CNS injury and disease

For many years, the central nervous system (CNS) was considered to be 'immune privileged', neither susceptible to nor contributing to inflammation. It is now appreciated that the CNS does exhibit features of inflammation, and in response to injury, infection or disease, resident CNS cells generate inflammatory mediators, including proinflammatory cytokines, prostaglandins, free radicals and complement, which in turn induce chemokines and adhesion molecules, recruit immune cells, and activate glial cells. Much of the key evidence demonstrating that inflammation and inflammatory mediators contribute to acute, chronic and psychiatric CNS disorders is summarised in this review. However, inflammatory mediators may have dual roles, with detrimental acute effects but beneficial effects in long-term repair and recovery, leading to complications in their application as novel therapies. These may be avoided in acute diseases in which treatment administration might be relatively short-term. Targeting interleukin (IL)-1 is a promising novel therapy for stroke and traumatic brain injury, the naturally occurring antagonist (IL-1ra) being well tolerated by rheumatoid arthritis patients. Chronic disorders represent a greater therapeutic challenge, a problem highlighted in Alzheimer's disease (AD); significant data suggested that anti-inflammatory agents might reduce the probability of developing AD, or slow its progression, but prospective clinical trials of nonsteroidal anti-inflammatory drugs or cyclooxygenase inhibitors have been disappointing. The complex interplay between inflammatory mediators, ageing, genetic background, and environmental factors may ultimately regulate the outcome of acute CNS injury and progression of chronic neurodegeneration, and be critical for development of effective therapies for CNS diseases.