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Traditionally, arterial hypertension and subsequent end-organ damage have been attributed to haemodynamic factors, but increasing evidence indicates that inflammation also contributes to the deleterious consequences of this disease. The immune system has evolved to prevent invasion of foreign microorganisms and to promote tissue healing after injury. However, this beneficial activity comes at a cost of collateral damage when the immune system overreacts to internal injury, such as prehypertension. Over the past few years, important findings have revolutionized hypertension research. Firstly, in 2007, a seminal paper showed that adaptive immunity is involved in the pathogenesis of hypertension. Secondly, salt storage in the skin and its consequences for cardiovascular physiology were discovered. Thirdly, after the discovery that salt promotes the differentiation of CD4+ T cells into TH 17 cells, it was demonstrated that salt directly changes several cells of the innate and adaptive immune system and aggravates autoimmune disease but may improve antimicrobial defence. Herein, we will review pathways of activation of immune cells by salt in hypertension as the framework for understanding the multiple roles of salt and immunity in arterial hypertension and autoimmune disease. LINKED ARTICLES: This article is part of a themed section on Immune Targets in Hypertension. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.12/issuetoc. [ABSTRACT FROM AUTHOR]

Background and Purpose: Andrographolide is a diterpenoid lactone isolated from a traditional medicinal herb, Andrographis paniculata. It possesses potent anti-inflammatory activity. The present study examined potential therapeutic effects of andrographolide on cerebral ischaemia using a rat model with permanent middle cerebral artery occlusion (pMCAO).Experimental Approach: The MCA in rats was permanently occluded (by cautery), and 24 h later neurological effects were assessed with behavioural scores. Infarct volume and microglial activation were determined histologically. The p65 form of the transcription factor, nuclear factor-κB (NF-κB), was measured by Western blot, and cytokines by immunoassay of brain extracts.Key Results: Andrographolide, given i.p. 1 h after pMCAO, reduced infarct volume with a maximum reduction of approximately 50% obtained at 0.1 mg·kg(-1). Neurological deficits were also reduced by andrographolide, reflecting a correlation between infarct volume and neurological deficits. pMCAO was found to induce activation of microglia and elevate tumour necrosis factor (TNF)-α, interleukin (IL)-1β and prostaglandin (PG)E(2) in the ischaemic brain areas. Andrographolide (0.1 mg·kg(-1)) significantly attenuated or abolished these effects. In addition, andrographolide suppressed the translocation of p65 from cytosol to nucleus, indicating reduced NF-κB activation.Conclusions and Implications: Andrographolide exhibited neuroprotective effects, with accompanying suppression of NF-κB and microglial activation, and reduction in the production of cytokines including TNF-α and IL-1β, and pro-inflammatory factors such as PGE(2). Our findings suggest that andrographolide may have therapeutic value in the treatment of stroke. [ABSTRACT FROM AUTHOR]

Background and Purpose: Constitutive activation of the signal transducer and activator of transcription 3 (STAT3) pathway is frequently encountered in several human cancers including multiple myeloma (MM). Thus, agents that suppress STAT3 phosphorylation have a potential for treatment of MM. In the present report, we investigated whether thymoquinone (TQ), the main component isolated from the medicinal plant Nigella sativa, modulated the STAT3 signalling pathway in MM cells.Experimental Approach: The effect of TQ on both constitutive and IL-6-induced STAT3 activation, associated protein kinases, STAT3-regulated gene products involved in proliferation, survival and angiogenesis, cellular proliferation and apoptosis in MM cells, was investigated.Key Results: We found that TQ inhibited both constitutive and IL-6-inducible STAT3 phosphorylation which correlated with the inhibition of c-Src and JAK2 activation. Vanadate reversed the TQ-induced down-regulation of STAT3 activation, suggesting the involvement of a protein tyrosine phosphatase. Indeed, we found that TQ can induce the expression of Src homology-2 phosphatase 2 that correlated with suppression of STAT3 activation. TQ also down-regulated the expression of STAT3-regulated gene products, such as cyclin D1, Bcl-2, Bcl-xL, survivin, Mcl-1 and vascular endothelial growth factor. Finally, TQ induced the accumulation of cells in sub-G1 phase, inhibited proliferation and induced apoptosis, as indicated by poly ADP ribose polymerase cleavage. TQ also significantly potentiated the apoptotic effects of thalidomide and bortezomib in MM cells.Conclusions and Implications: Our study has identified STAT3 signalling as a target of TQ and has thus raised its potential application in the prevention and treatment of MM and other cancers. [ABSTRACT FROM AUTHOR]

Background and Purpose: The mechanisms of anti-inflammatory actions of statins, 3-hydroxy-3-methylglutaryl CoA (HMG-CoA) reductase inhibitors, remain unclear. We investigated the effects of statins on interleukin (IL)-6-induced monocyte chemo-attractant protein (MCP)-1 expression and monocyte chemotaxis.Experimental Approach: Cultures of human aortic endothelial cells (HAECs) were stimulated with IL-6 in the absence and presence of statins. Gene expression and protein secretion of MCP-1, phosphorylation of Janus kinase (JAK) and the signal transducers and activators of transcription (STAT) pathway, and human monocyte migration were examined.Key Results: IL-6 plus its soluble receptor sIL-6R (IL-6/sIL-6R) promoted THP-1 monocyte migration, and increased gene expression and protein secretion of MCP-1, more than IL-6 alone or sIL-6R alone. Various statins inhibited IL-6/sIL-6R-promoted monocyte migration and MCP-1 expression in HAECs. Co-incubation of mevalonate and geranylgeranyl pyrophosphate, but not farnesyl pyrophosphate, reversed the inhibitory effects of statins on MCP-1 expression. Geranylgeranyl transferase inhibitor, but not farnesyl transferase inhibitor, suppressed IL-6/sIL-6R-stimulated MCP-1 expression. IL-6/sIL-6R rapidly phosphorylated JAK1, JAK2, TYK2, STAT1 and STAT3, which were inhibited by statins. Transfection of STAT3 small interfering RNA (siRNA), but not STAT1 siRNA, attenuated the ability of IL-6/sIL-6R to enhance THP-1 monocyte migration. In addition, statins blocked IL-6/sIL-6R-induced translocation of STAT3 to the nucleus.Conclusions and Implications: Statins suppressed IL-6/sIL-6R-induced monocyte chemotaxis and MCP-1 expression in HAECs by inhibiting JAK/STAT signalling cascades, explaining why statins have anti-inflammatory properties beyond cholesterol reduction. [ABSTRACT FROM AUTHOR]

Background and Purpose: Th9 cells represent a recently defined subset of CD4+ T-helper cells, characterized by a high production of IL-9. They are found at increased frequency in lesions of atopic dermatitis, where IL-9 is also elevated. As histamine is up-regulated in lesions of inflammatory skin diseases, we investigated the expression profile of histamine receptors and their functional role on Th9 cells.Experimental Approach: Naïve CD4+ T-cells were purified from human peripheral blood mononuclear cells, using magnetic beads and further differentiated into Th9 cells. During differentiation, cells were additionally stimulated with histamine receptor agonists or left untreated. Histamine receptor expression as well as IL-9 production was measured.Key Results: As proof of a successful differentiation, IL-9 production was measured at mRNA and protein level. Expression of mRNA for histamine H1 , H2 and H4 receptors were up-regulated in differentiated Th9 cells compared to Th0 cells, while no mRNA for the H3 receptor was detectable. Stimulation of Th9 cells with histamine significantly up-regulated expression of mRNA and protein for IL-9 . Experiments with specific histamine receptor agonists and antagonists revealed that this up-regulation was mediated by H4 receptors.Conclusions and Implications: In summary, our study demonstrates a functional role for histamine H4 receptors on Th9 cells, which might amplify the pro-inflammatory potency of these cells. Together with earlier studies on Th2 and Th17 cells, this study underlines the promising approach for the use of H4 receptor antagonists in inflammatory and allergic diseases such as atopic dermatitis.Linked Articles: This article is part of a themed section on New Uses for 21st Century. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v177.3/issuetoc. [ABSTRACT FROM AUTHOR]

Background and Purpose: The adaptive immune response and IL-17A contribute to renal damage in several experimental models of renal injury.Experimental Approach: To evaluate the role of the adaptive immune response, 5/6 nephrectomy was performed in wildtype DBA/1J mice and in recombination-activating gene-1 (RAG-1) deficient mice that lack B and T-cells. To assess the role of IL-17A, we carried out 5/6 nephrectomy in IL-17A deficient mice. Flow cytometric analysis, immunohistochemistry and RT-PCR were used.Key Results: Infiltration of CD3+ T-cells in the remnant kidney was increased after 5/6 nephrectomy in wildtype mice, along with a robust induction of IL-17A production in CD4+ T and γδ T-cells. After 5/6 nephrectomy, wildtype mice developed albuminuria in the nephrotic range over 10 weeks. This was accompanied by severe glomerular sclerosis and tubulointerstitial injury, and as well as renal mRNA expression of markers of inflammation and fibrosis (the chemokine CCL2, plasminogen activator inhibitor-1; PAI-1 and neutrophil gelatinase-associated lipocalin; NGAL). Unexpectedly, RAG-1 deficient mice and IL-17A deficient mice developed renal injury, similar to that in wildtype mice. No differences were found for albuminuria, glomerular sclerosis, tubulointerstitial injury and mRNA expression of CCL2, PAI-1 and NGAL. Mortality did not differ between the three groups.Conclusions and Implications: Numbers of CD3+ T-cells and IL-17A+ lymphocytes infiltrating the kidney were increased after 5/6 nephrectomy. In contrast to other experimental models of renal injury, genetic deficiency of the adaptive immune system or of IL-17A did not attenuate induction or progression of chronic kidney disease after 5/6 nephrectomy.Linked Articles: This article is part of a themed section on Immune Targets in Hypertension. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.12/issuetoc. [ABSTRACT FROM AUTHOR]

Background and Purpose: Myocardial infarction (MI) is one of the leading causes of death in China and often results in the development of heart failure. In this work, we tested the therapeutic role of Interleukin-19 (IL-19) in mice with MI and investigated the underlying molecular mechanism.Experimental Approach: Mice were subjected to MI by ligation of left anterior descending coronary artery (LAD) and treated with IL-19 (10ng g-1 ; i.p.).Key Results: Protein expression of IL-19 and its receptor in myocardium were upregulated 24 hrs post-MI in male mice. IL-19 treatment decreased infarct and apoptosis in myocardium, accompanied by enhanced haem oxygenase-1 (HO-1) activities and reduced malondialdehyde (MDA) formation. Pretreatment with IL-19 upregulated HO-1 expression in cultured neonatal mouse ventricular myocytes and attenuated oxygen-glucose deprivation (OGD)-induced injuries in vitro. Furthermore, IL-19 preserved cardiac function and improved survival of mice with MI. IL-19 reduced inflammatory infiltrates and suppressed formation of TNF-α, IL-1β, and IL-6. More importantly, IL-19 inhibited polarization toward proinflammatory M1 macrophages and stimulated M2 macrophage polarization in myocardium of mice with MI. IL-19 enhanced protein levels of vascular endothelial growth factor (VEGF) and promoted angiogenesis in myocardium of mice with MI. In addition, IL-19 treatment increased DNA-binding of the transcription factor STAT3 in myocardium of mice with MI.Conclusions and Implications: Treatment with exogenous IL-19 attenuated acute ischemic injury and improved survival of mice with MI. The mechanisms underlying these effects involved induction of HO-1, M2 macrophage polarization, angiogenesis, and STAT3 activation. [ABSTRACT FROM AUTHOR]

Background and Purpose: Non-alcoholic steatohepatitis (NASH) is the most severe form of non-alcoholic fatty liver disease and is a serious public health problem around the world. There are currently no approved treatments for NASH. FGF21 has recently emerged as a promising drug candidate for metabolic diseases. However, the disadvantages of FGF21 as a clinically useful medicine include its short plasma half-life and poor drug-like properties. Here, we have explored the effects of PsTag600-FGF21, an engineered long-acting FGF21 fusion protein, in mice with NASH and describe some of the underlying mechanisms.Experimental Approach: A long-acting FGF21 was prepared by genetic fusion with a 600 residues polypeptide (PsTag600). We used a choline-deficient high-fat diet-induced model of NASH in mice. The effects on body weight, insulin sensitivity, inflammation and levels of hormones and metabolites were studied first. We further investigated whether PsTag600-FGF21 attenuated inflammation through the Th17-IL17A axis and the associated mechanisms.Key Results: PsTag600-FGF21 dose-dependently reduced body weight, blood glucose, and insulin and lipid levels and reversed hepatic steatosis. PsTag600-FGF21 enhanced fatty acid activation and mitochondrial β-oxidation in the liver. The profound reduction in hepatic inflammation in NASH mice following PsTag600-FGF21 was associated with inhibition of IL17A expression in Th17 cells. Furthermore, PsTag600-FGF21 depended on adiponectin to exert its suppression of Th17 cell differentiation and IL17A expression.Conclusions and Implications: Our data have uncovered some of the mechanisms by which PsTag600-FGF21 suppresses hepatic inflammation and further suggest that PsTag600-FGF21 could be an effective approach in NASH treatment. [ABSTRACT FROM AUTHOR]

Background and Purpose: Numerous in vitro studies have suggested that digoxin suppresses inflammation and alters lipid metabolism. However, the effect of dioxin on atherosclerosis is poorly understood. The present study was conducted to determine whether digoxin affects the development of atherosclerosis in a murine model of atherosclerotic disease.Experimental Approach: Apolipoprotein E-deficient mice maintained on a Western-type diet were administered PBS (control), low-dose digoxin (1 mg · kg(-1) · day(-1)) or high-dose digoxin (2 mg · kg(-1) · day(-1)) via i.p. injection for 12 weeks.Key Results: Digoxin dose-dependently reduced atherosclerotic lesion formation and plasma lipid levels (reductions of 41% in total cholesterol, 54% in triglycerides and 20% in low-density lipoprotein cholesterol in the high-dose digoxin-treated group). Moreover, treatment with digoxin markedly attenuated IL-17A expression and IL-17A-related inflammatory responses and increased the abundance of regulatory T cells (Tregs).Conclusions and Implications: Our data demonstrate that digoxin acts as a specific antagonist of retinoid-related orphan receptor-γ to decrease atherosclerosis by suppressing lipid levels and IL-17A-related inflammatory responses. [ABSTRACT FROM AUTHOR]

Background and Purpose: Sepsis is a life-threatening clinical condition characterized by uncontrolled inflammatory responses and is a major cause of death in intensive care units. Histone deacetylase (HDAC) inhibitors have recently exhibited anti-inflammatory properties. MAPK phosphatase (MKP) suppresses MAPK signalling, which plays an important role in inflammatory responses. The purpose of this study was to investigate the protective mechanisms of Compound 9a, a newly synthetized HDAC inhibitor, against septic injury.Experimental Approach: The anti-inflammatory properties of Compound 9a were assayed in LPS-stimulated RAW264.7 cells. In vivo, polymicrobial sepsis was induced in C57BL/6 mice by caecal ligation and puncture (CLP). The mice were treated with Compound 9a (i.p., 10 mg∙kg(-1) ) 2 h before and immediately after CLP.Key Results: Compound 9a inhibited the increased production of TNF-α, IL-6 and NO in LPS-stimulated RAW264.7 cells. In mice with CLP, Compound 9a improved survival rate, attenuated organ injuries and decreased serum TNF-α and IL-6 levels. CLP increased expression of toll-like receptor 4, phosphorylated (p)-p38, p-JNK and p-ERK proteins, which was attenuated by Compound 9a. Compound 9a decreased MKP-1 association with HDAC1 and enhanced MKP-1 acetylation and enhanced MKP-1 association with p-p38 and p-ERK. Moreover, the inhibitory effects of Compound 9a on serum cytokine levels and phosphorylation of MAPK were abolished by MKP-1 siRNA.Conclusions and Implications: Our findings suggest that Compound 9a protected against septic injury by suppressing MAPK-mediated inflammatory signalling. [ABSTRACT FROM AUTHOR]

Microglia are critical nervous system-specific immune cells serving as tissue-resident macrophages influencing brain development, maintenance of the neural environment, response to injury and repair. As influenced by their environment, microglia assume a diversity of phenotypes and retain the capability to shift functions to maintain tissue homeostasis. In comparison with peripheral macrophages, microglia demonstrate similar and unique features with regards to phenotype polarization, allowing for innate immunological functions. Microglia can be stimulated by LPS or IFN-γ to an M1 phenotype for expression of pro-inflammatory cytokines or by IL-4/IL-13 to an M2 phenotype for resolution of inflammation and tissue repair. Increasing evidence suggests a role of metabolic reprogramming in the regulation of the innate inflammatory response. Studies using peripheral immune cells demonstrate that polarization to an M1 phenotype is often accompanied by a shift in cells from oxidative phosphorylation to aerobic glycolysis for energy production. More recently, the link between polarization and mitochondrial energy metabolism has been considered in microglia. Under these conditions, energy demands would be associated with functional activities and cell survival and thus, may serve to influence the contribution of microglia activation to various neurodegenerative conditions. This review examines the polarization states of microglia and their relationship to mitochondrial metabolism. Additional supporting experimental data are provided to demonstrate mitochondrial metabolic shifts in primary microglia and the BV-2 microglia cell line induced under LPS (M1) and IL-4/IL-13 (M2) polarization. [ABSTRACT FROM AUTHOR]

Background and Purpose Leptin, an adipokine synthesized by the placenta during pregnancy, has been proposed for the management of preterm labour ( PTL), as it is able to prevent in vitro uterine contractility and remodelling associated with labour onset. Another common feature of labour onset is the phenotypic switch of myometrial smooth muscle cells from a proliferative to a hypertrophic state. As proliferative effects have been demonstrated for leptin in other tissues, we aimed to investigate its ability to induce myometrial proliferation and thus to maintain uterine quiescence. Experimental Approach We stimulated human primary myometrial smooth muscle cells with leptin in the presence or absence of receptor antagonists or signalling pathway inhibitors. Key Results Leptin induced myometrial cell proliferation in a biphasic manner. At 6.25 ng·mL−1, leptin-induced proliferation was mediated by the leptin receptor and required the early activation of ERK1/2. At a concentration above 25 ng·mL−1, leptin induced direct non-specific stimulation of the IL-6 receptor, leading to NF-κB activation, and exerted anti-proliferative effects. However, at 50 ng·mL−1, leptin re-induces proliferation via IL-6 receptor stimulation that requires STAT3 and delayed ERK1/2 activation. Conclusions and Implications These data bring new insights into leptin signalling-induced myometrial proliferation and its interrelationship with the IL-6/ IL-6 receptor axis. In the light of our previous work, the present study emphasizes the potential value of leptin in the pharmacological management of PTL and it also strengthens the hypothesis that leptin might be a contributory factor in the parturition-related disorders observed in obese women. [ABSTRACT FROM AUTHOR]

Background and Purpose Bone resorption induced by interleukin-1β ( IL-1β) and tumour necrosis factor ( TNF-α) is synergistically potentiated by kinins, partially due to enhanced kinin receptor expression. Inflammation-induced bone resorption can be impaired by IL-4 and IL-13. The aim was to investigate if expression of B1 and B2 kinin receptors can be affected by IL-4 and IL-13. Experimental Approach We examined effects in a human osteoblastic cell line ( MG-63), primary human gingival fibroblasts and mouse bones by IL-4 and IL-13 on mRNA and protein expression of the B1 and B2 kinin receptors. We also examined the role of STAT6 by RNA interference and using Stat6-/- mice. Key Results IL-4 and IL-13 decreased the mRNA expression of B1 and B2 kinin receptors induced by either IL-1β or TNF-α in MG-63 cells, intact mouse calvarial bones or primary human gingival fibroblasts. The burst of intracellular calcium induced by either bradykinin ( B2 agonist) or des- Arg10-Lys-bradykinin ( B1 agonist) in gingival fibroblasts pretreated with IL-1β was impaired by IL-4. Similarly, the increased binding of B1 and B2 ligands induced by IL-1β was decreased by IL-4. In calvarial bones from Stat6-deficient mice, and in fibroblasts in which STAT6 was knocked down by siRNA, the effect of IL-4 was decreased. Conclusions and Implications These data show, for the first time, that IL-4 and IL-13 decrease kinin receptors in a STAT6-dependent mechanism, which can be one important mechanism by which these cytokines exert their anti-inflammatory effects and impair bone resorption. [ABSTRACT FROM AUTHOR]

Background and Purpose: Inflammatory pain is triggered by activation of pathways leading to the release of mediators such as bradykinin, prostaglandins, interleukins, ATP, growth factors and protons that sensitize peripheral nociceptors. The activation of acid-sensitive ion channels (ASICs) may have particular relevance in the development and maintenance of inflammatory pain. ASIC3 is of particular interest due to its restricted tissue distribution in the nociceptive primary afferent fibres and its high sensitivity to protons.Experimental Approach: To examine the contribution of ASIC3 to the development and maintenance of muscle pain and inflammatory pain, we studied the in vivo efficacy of a selective ASIC3 inhibitor, APETx2, in rats.Key Results: Administration of APETx2 into the gastrocnemius muscle prior to the administration of low pH saline prevented the development of mechanical hypersensitivity, whereas APETx2 administration following low-pH saline was ineffective in reversing hypersensitivity. The prevention of mechanical hypersensitivity produced by acid administration was observed whether APETx2 was applied via i.m. or i.t. routes. In the complete Freund's adjuvant (CFA) inflammatory pain model, local administration of APETx2 resulted in a potent and complete reversal of established mechanical hypersensitivity, whereas i.t. application of APETx2 was ineffective.Conclusions and Implications: ASIC3 contributed to the development of mechanical hypersensitivity in the acid-induced muscle pain model, whereas ASIC3 contributed to the maintenance of mechanical hypersensitivity in the CFA inflammatory pain model. The contribution of ASIC3 to established hypersensitivity associated with inflammation suggests that this channel may be an effective analgesic target for inflammatory pain states. [ABSTRACT FROM AUTHOR]

Background and Purpose: Cucurbitacin R, a natural anti-inflammatory product, has been shown to exhibit activity against both adjuvant-induced arthritis and delayed-type hypersensitivity reactions induced by various agents. Previous studies have demonstrated that the effects of cucurbitacin R stem from its inhibition of both cytokine production and lymphocyte proliferation.Experimental Approaches: Effects of cucurbitacin R were investigated on lipopolysaccharide-stimulated RAW 264.7 cells. Cell cycle evolution was analysed by flow cytometry, detection of apoptosis by DNA ladder, Bcl-2, p21, p53, Bax, cleaved caspase-1 (p10), caspase-9, and caspase-3, cleaved caspase (p17) and interleukin-1beta detection was followed by Western blot analysis and mRNA expression with quantitative real time reverse transcription-polymerase chain reaction (qRT-PCR).Key Results: Cucurbitacin R was found to induce apoptosis in lipopolysaccharide-stimulated RAW 264.7 macrophages through the inhibition of Bcl-2 expression, which regulates pro-inflammatory caspase-1 activation and interleukin-1beta release. Also, cucurbitacin R arrested the cell cycle in the G(2)/M phase and increased the subG(0) population in lipopolysaccharide-stimulated RAW 264.7 macrophages. Moreover, it increased the expression of proteins p53 and p21, down-regulated the expression of Bcl-2, activated the activity of caspase-1 and augmented the production of interleukin-1beta. Finally, the transfection of RAW 264.7 macrophages with a Bcl-2 expression plasmid produced the inhibition of apoptosis and caspase-1 activation/interleukin-1beta release induced by cucurbitacin R in RAW 264.7 cells.Conclusions and Implications: Taken together, these results point to a new apoptotic process in which interleukin-1beta release is directly regulated by Bcl-2 status; this contributes to the evidence that apoptotic processes do not induce inflammation. [ABSTRACT FROM AUTHOR]

Background and Purpose: Interleukin (IL)-1beta-induced matrix metalloproteinase (MMP-9) expression is regulated by mitogen activated protein kinases (MAPKs) and NF-kappaB. IL-1beta also stimulates transactivation of growth factor receptors and phosphatidylinositol 3-kinase (PI3K)/Akt., leading to the expression of inflammatory proteins. Here, we investigated whether these transactivation mechanisms participated in IL-1beta-induced MMP-9 expression in A549 cells.Experimental Approach: A549 cells were treated with/without pharmacological inhibitors and neutralizing antibody or transfected with dominant negative mutants and siRNA of particular protein kinases before stimulation with IL-1beta. Cell migration was measured by in vitro scratch assay. Expression and enzymatic activity of MMP-9 were analysed by Western blot and gelatin zymography. Transcriptional activity of MMP-9 was analysed by RT-PCR, chromatin immunoprecipitation and promoter assays.Key Results: Inhibition of MMP-9 expression by inhibitors of Src (PP1), platelet-derived growth factor (PDGF) receptor and epithelial growth factor (EGF) receptor or transfection with siRNA for Src and Akt prevented IL-1beta-induced migration of A549 cells. These tyrosine kinases were involved through phosphorylation of Src, PDGF, or EGF receptors (EGFRs) via the formation of Src/PDGFR or Src/EGFR complexes, attenuated by PP1. IL-1beta-induced MMP-9 expression through EGFR transactivation was diminished by inhibitors of MMPs and heparin-binding EGF-like factor (HB-EGF), or a neutralizing HB-EGF antibody. IL-1beta-stimulated activation and translocation of Akt and NF-kappaB (p65); the recruitment of activated NF-kappaB (p65) to the MMP-9 promoter region was attenuated by LY294002.Conclusions and Implications: IL-1beta-induced MMP-9 expression and cell migration was mediated through c-Src-dependent transactivation of EGFR/PDGFR/PI3K/Akt linking to the NF-kappaB pathway in A549 cells. [ABSTRACT FROM AUTHOR]

Background and Purpose: Inflammatory response and cytokine activation are markedly stimulated after myocardial infarction, and contribute to cardiac remodelling. Interleukin-6 (IL-6), a pro-inflammatory cytokine, has pleiotropic effects on cardiac remodelling. Adenosine, released by all cell types, binds to a class of G protein-coupled receptors to induce various cardiovascular effects. The aim of this work was to investigate whether activation of adenosine receptors, particularly A(2B) adenosine receptors, could stimulate IL-6 secretion in cardiac fibroblasts (CFs).Experimental Approach: elisa was used to assess IL-6 concentration in supernatant, and immunostaining was used to analyse IL-6 protein level in CFs. The levels of phosphorylated and total p38, extracellular signal-regulated kinase, c-Jun N-terminal kinase and protein kinase C-delta (PKC-delta) were determined by Western blot analysis.Key Results: Adenosine-5'-N-ethyluronamide (NECA), a stable adenosine analogue, dose- and time-dependently stimulated IL-6 secretion in CFs. The effect of NECA was dose-dependently inhibited by an A(2B) antagonist, and silencing of the A(2B) receptor also inhibited IL-6 secretion. By using PKC isoform-selective inhibitors and translocation peptide inhibitors, the PKC-delta isoform was found to be involved in the up-regulation of IL-6 production. Inhibition of p38 by SB203580, and adenoviral transfer of dominant-negative p38 inhibited NECA-induced IL-6 production. Furthermore, PKC-delta functioned as an upstream regulator of p38 MAPK in this process.Conclusions and Implications: We demonstrated a novel relationship between adenosine and IL-6 secretion, in that IL-6 secretion induced by NECA was mediated by adenosine A(2B) receptor activation in CFs and was dependent on a PKCdelta-P38 pathway. [ABSTRACT FROM AUTHOR]

Background and Purpose: Atherosclerotic plaque rupture and thrombosis are the main cause of acute coronary syndrome. The study was aimed to test the hypothesis that oral administration of rapamycin may attenuate inflammation, inhibit progression and enhance stability of atherosclerotic plaques.Experimental Approach: Thirty New Zealand rabbits were subjected to balloon-induced endothelial injury of the abdominal aorta and were fed a diet of 1% cholesterol for 20 weeks. From week 9 to week 20, the animals were treated with oral rapamycin (0.5 mg x kg(-1) x day(-1); group A), oral simvastatin (5 mg x kg(-1) x day(-1); group B) and no drugs (group C). At the end of week 20, all rabbits were challenged with injection of Chinese Russell's viper venom and histamine. Serological, ultrasonographic, pathological, immunohistochemical and gene expression studies were performed.Key Results: Rapamycin significantly increased the thickness of the fibrous caps and decreased plaque vulnerability index in group A rabbits. Serum lipid levels were higher whereas plaque burden was lower in group A than in group B (P < 0.05). The incidence of plaque rupture in group A (0%) and group B (0%) was significantly lower than that in group C (56.0%, P < 0.05).Conclusions and Implications: Oral administration of rapamycin effectively attenuated inflammation, inhibited progression and enhanced stability of atherosclerotic plaques in rabbits, without altering serum lipid levels. Our findings suggest a novel approach to the treatment of atherosclerosis. [ABSTRACT FROM AUTHOR]

Background and Purpose: The adenosine 2B (A2B) receptor is the predominant adenosine receptor expressed in the colon. Acting through the A2B receptor, adenosine mediates chloride secretion, as well as fibronectin and interleukin (IL)-6 synthesis and secretion in intestinal epithelial cells. A2B receptor mRNA and protein expression are increased during human and murine colitis. However, the effect of the A2B receptor in the activation of the intestinal inflammatory response is not known. In this study, we examined the effect of A2B receptor antagonism on murine colitis.Experimental Approach: Dextran sodium sulphate (DSS)-treated mice and piroxicam-treated IL-10-/- mice were used as animal models of colitis. The A2B receptor-selective antagonist, ATL-801, was given in the diet.Key Results: Mice fed ATL-801 along with DSS showed a significantly lower extent and severity of colitis than mice treated with DSS alone, as shown by reduced clinical symptoms, histological scores, IL-6 levels and proliferation indices. The administration of ATL-801 prevented weight loss, suppressed the inflammatory infiltrate into colonic mucosa and decreased epithelial hyperplasia in piroxicam-treated IL-10-/- mice. IL-6 and keratinocyte-derived chemokine (KC) concentrations in the supernatants of colonic organ cultures from colitic mice were significantly reduced by ATL-801 administration.Conclusions and Implications: Taken together, these data demonstrate that the intestinal epithelial A2B receptor is an important mediator of pro-inflammatory responses in the intestine and that A2B receptor blockade may be an effective therapeutic strategy to treat inflammatory bowel disease. [ABSTRACT FROM AUTHOR]

Background: Macrophage elastase (MMP-12) is involved in the inflammatory process of chronic obstructive pulmonary disease (COPD). The aim of this study was to investigate in mice the effect of MMP-12 inhibition on the inflammatory process induced by cigarette smoke (CS) or by lipopolysaccharide (LPS) exposure of the airways.Experimental Approach: C57BL/6 mice were given, orally, either the selective MMP-12 inhibitor AS111793 (3, 10, 30 and 100 mg kg(-1)), the PDE-4 inhibitor roflumilast (3 mg kg(-1)) or vehicle, then exposed to CS (for 3 days) or to LPS (100 microg mL(-1), 30 min). Subsequent to the last smoke or LPS exposure, bronchoalveolar lavages (BAL) were performed and lungs were removed and homogenized to analyze various markers of inflammation at appropriate times.Key Results: Inhibition of MMP-12 by AS111793 (10 and 30 mg kg(-1)) was associated with a reduction of the increase in neutrophil number in BAL fluids after 4 days and of macrophages after 11 days. On day 4, AS111793 also significantly reduced all the inflammation markers that had increased after CS exposure, including soluble TNF receptors I and II, MIP-1gamma, IL-6 and pro-MMP-9 activity in BAL fluids, and KC/CXCL1, fractalkine/CX3CL1, TIMP-1 and I-TAC/CXCL11 in lung parenchyma. In contrast, inhibition of MMP-12 did not reduce neutrophil influx, pro-MMP-9 activity or KC/CXCL1 release in BAL fluids of mice exposed to LPS.Conclusion: Inhibition of MMP-12 with AS111793, reduced the inflammatory process associated with exposure of mice to CS, strongly suggesting a specific involvement of MMP-12 in lung inflammation following CS exposure. [ABSTRACT FROM AUTHOR]

Background and purpose:The glycosaminoglycan heparin has anti-inflammatory activity and is exclusively found in mast cells, which are localized within airway smooth muscle (ASM) bundles of asthmatic airways. Interleukin (IL)-13 induces the production of multiple inflammatory mediators from ASM including the eosinophil chemoattractant chemokine, eotaxin-1. Heparin and related glycosaminoglycan polymers having structurally heterogeneous polysaccharide side chains that varied in molecular weight, sulphation and anionic charge were used to identify features of the heparin molecule linked to anti-inflammatory activity.Experimental approach:Cultured human ASM cells were stimulated with interleukin (IL)-13 in the absence or presence of heparin and related polymers. Eotaxin-1 was quantified using chemokine antibody arrays and ELISA.Key results:Unfractionated heparin attenuated IL-13-dependent eotaxin-1 production and this effect was reproduced with low molecular weight heparins (3 and 6 kDa), demonstrating a minimum activity fragment of at least 3 kDa. N-desulphated, 20% re-N-acetylated heparin (anticoagulant) was ineffective against IL-13-dependent eotaxin-1 production compared with 90% re-N-acetylated (anticoagulant) or O-desulphated (non-anticoagulant) heparin, suggesting a requirement for N-sulphation independent of anticoagulant activity. Other sulphated molecules with variable anionic charge and molecular weight exceeding 3 kDa (dextran sulphate, fucoidan, chondroitin sulphate B) inhibited IL-13-stimulated eotaxin-1 release to varying degrees. However, non-sulphated dextran had no effect.Conclusions:Inhibition of IL-13-dependent eotaxin-1 release by heparin involved but did not depend upon sulphation, though loss of N-sulphation reduced the attenuating activity, which could be restored by N-acetylation. This anti-inflammatory effect was also partially dependent on anionic charge, but independent of molecular size above 3 kDa and the anticoagulant action of heparin.British Journal of Pharmacology (2008) 154, 833–842; doi:10.1038/bjp.2008.109; published online 21 April 2008 [ABSTRACT FROM AUTHOR]

Background and Purpose: Among the agents employed to manage osteoarthritis, chondroitin sulphate (CS) is a natural glycosaminoglycan with an anti-inflammatory effect on joint cells. CS might also influence the inflammatory component of atherosclerosis. Our aim was to examine the effect of CS administration on vascular injury and on markers of systemic inflammation in a rabbit model of atherosclerosis aggravated by systemic inflammation provoked by chronic antigen-induced arthritis.Experimental Approach: Atherosclerosis was induced in rabbits by maintaining them on a hyperlipidaemic diet after producing an endothelial lesion in the femoral arteries. Simultaneously, chronic arthritis was induced in these animals by repeated intraarticular injections of ovalbumin in previously immunized rabbits. A group of these rabbits were treated prophylactically with CS (100 mg kg(-1)day(-1)) and when the animals were killed, serum and peripheral blood mononuclear cells (PBMC) were isolated. Furthermore, femoral arteries and thoracic aorta were used for gene expression studies and histological examination.Key Results: CS administration reduced the concentration of the proinflammatory molecules C-reactive protein and IL-6 in serum. Likewise, CS inhibited the expression of CCL2/monocyte chemoattractant protein (MCP)-1 and cyclooxygenase (COX)-2 in PBMC, and reduced the nuclear translocation of nuclear factor-kappaB. In the femoral lesion, CS also diminished the expression of CCL2 and COX-2, as well as the ratio of the intima/media thickness. Moreover, CS decreased the percentage of rabbits with atherosclerosis and chronic arthritis that developed vascular lesions in the aorta.Conclusions and Implications: These findings suggest that CS treatment may to some extent impede the progression of atherosclerosis. [ABSTRACT FROM AUTHOR]

Background and Purpose: Bovine glycomacropeptide (BGMP) is an inexpensive, non-toxic milk peptide with anti-inflammatory effects in rat experimental colitis but its mechanism of action is unclear. It is also unknown whether BGMP can ameliorate inflammation in proximal regions of the intestine. Our aim was therefore two-fold: first, to determine the anti-inflammatory activity of BGMP in the ileum; second, to characterise its mechanism of action.Experimental Approach: We used a model of ileitis induced by trinitrobenzenesulphonic acid in rats. Rats were treated orally with BGMP and its efficacy compared with that of oral 5-aminosalicylic acid or vehicle, starting 2 days before ileitis induction.Key Results: BGMP pretreatment (500 mg kg(-1) day(-1)) resulted in marked reduction of inflammatory injury, as assessed by lower extension of necrosis and damage score, myeloperoxidase, alkaline phosphatase, inducible nitric oxide synthase, interleukin 1beta, tumour necrosis factor and interleukin 17. These effects were generally comparable to those of 5-aminosalicylic acid (200 mg kg(-1) day(-1)). Neither compound affected the production of interferon gamma, tumour necrosis factor and interleukin 2 by mesenteric lymph node cells isolated from animals with ileitis. The expression of Foxp3 was increased in ileitis and not reduced significantly by BGMP or aminosalicylate treatment.Conclusions and Implications: These results demonstrate that BGMP has anti-inflammatory activity in the ileum with similar efficacy to 5-aminosalicylic acid. The mechanism of action may involve Th17 and regulatory T cells and perhaps macrophages but probably not Th1 lymphocytes. Patients with Crohn's ileitis may benefit from treatment with BGMP. [ABSTRACT FROM AUTHOR]

Background and Purpose: Lung epithelial cells express pattern recognition receptors, which react to bacteria. We have evaluated the effect of Gram-positive and Gram-negative bacteria on interleukin-8 (CXCL8) release from epithelial cells and the integrity of the epithelial barrier.Experimental Approach: Primary cultures of human airway epithelial cells and the epithelial cell line A549 were used, and CXCL8 release was measured after exposure to Gram-negative or Gram-positive bacteria. Epithelial barrier function was assessed in monolayer cultures of A549 cells.Results: Gram-positive bacteria Staphylococcus aureus or Streptococcus pneumoniae, induced release of CXCL8 from human airway epithelial cells. These bacteria also disrupted barrier function in A549 cells, an effect mimicked by CXCL8 and blocked by specific binding antibodies to CXCL8. Gram-negative bacteria Escherichia coli or Pseudomonas aeruginosa induced greater release of CXCL8 than Gram-positive bacteria. However, Gram-negative bacteria did not affect epithelial barrier function directly, but prevented disruption induced by Gram-positive bacteria. These effects of Gram-negative bacteria on barrier function were mimicked by FK565, an agonist of the nucleotide-binding oligomerization domain 1 (NOD1) receptor, but not by the Toll-like receptor (TLR) 4 agonist bacterial lipopolysaccharide. Neither the Gram-negative bacteria nor FK565 blocked CXCL8 release.Conclusions: These data show differential functional responses induced by Gram-negative and Gram-positive bacteria in human lung epithelial cells. The NOD1 receptors may have a role in preventing disruption of the epithelial barrier in lung, during inflammatory states. [ABSTRACT FROM AUTHOR]

Background and Purpose: Glycyrrhizae radix has been widely used as a cytoprotective, plant-derived medicine. We have identified a flavanoid, liquiritigenin, as an active component in extracts of Glycyrrhizae radix. This research investigated the effects of liquiritigenin on the induction of inducible NOS (iNOS) and proinflammatory cytokines by lipopolysaccharide (LPS) in Raw264.7 cells, and on paw oedema in rats.Experimental Approach: iNOS expression was determined by western blotting, real-time reverse transcription-PCR and reporter gene analyses. Tumour necrosis factor-alpha (TNF-alpha), interleukin (IL)-1beta and IL-6 were assayed by ELISA. Gel shift assay and immunoblotting were used to assess NF-kappaB activation. The effect of liquiritigenin on acute inflammation in vivo was evaluated using carrageenan-induced paw oedema.Key Results: Treatment of Raw264.7 cells with liquiritigenin caused inhibition of LPS-induced NF-kappaB DNA binding activity, due to repression of I-kappaBalpha phosphorylation and degradation. Liquiritigenin treatment prevented LPS from increasing the levels of iNOS protein and mRNA in a concentration-dependent manner. Liquiritigenin also suppressed the production of TNF-alpha, IL-1beta and IL-6 from Raw264.7 cells after LPS. In rats, liquiritigenin treatment inhibited formation of paw oedema induced by carrageenan.Conclusion and Implications: These results demonstrate that liquiritigenin exerts anti-inflammatory effects, which results from the inhibition of NF-kappaB activation in macrophages, thereby decreasing production of iNOS and proinflammatory cytokines. Our findings showing inhibition by liquiritigenin of paw oedema as well as inflammatory gene induction will help to understand the pharmacology and mode of action of liquiritigenin, and of the anti-inflammatory use of Glycyrrhizae radix. [ABSTRACT FROM AUTHOR]

Background and Purpose: Our previous study showed that SM905, a novel artemisinin derivative, exhibited potent immunosuppressive activity. In this study, we evaluate preventive and therapeutic effect of SM905 on collagen-induced arthritis (CIA) in DBA/1 mice, and investigate its mechanisms both in inflammatory and autoimmune aspects of the disease.Experimental Approach: CIA was induced by type II bovine collagen (CII) in DBA/1 mice. SM905 was given orally either before (continuously 1 day before booster immunization) or after disease onset (continuously 14 days after booster immunization). Disease incidence and severity were monitored, mRNA expression of proinflammatory mediators was determined by real-time PCR, purified T cell proliferation was assessed using [(3)H]-thymidine incorporated assay, and T helper (Th) 17/Th1/Th2 type cytokine production was examined by ELISA.Key Results: Oral treatment with SM905 delayed disease onset, reduced arthritis incidence and severity, and suppressed the enhanced expression of pro-inflammatory cytokines, chemokines and chemokine receptors in draining lymph nodes. The CII-induced T cell proliferation and production of interleukin (IL)-17A by T cells were strikingly inhibited. Correspondingly, the mRNA expression of IL-17A and RORgamma t (a specific transcription factor for Th17) was also reduced. This effect was coupled with a striking reduction of IL-6 production, which has a critical role in Th17 development. In established arthritis, SM905 profoundly inhibited disease progression, reduced IL-17A and RORgamma t mRNA expression, and suppressed pro-inflammatory mediator expression in arthritic joints.Conclusions and Implications: SM905 had beneficial effects on CIA by suppressing inflammatory and pathogenic Th17 responses. [ABSTRACT FROM AUTHOR]

Background and Purpose: Leukotriene B(4) (LTB(4)), formed by the sequential actions of the 5-lipoxygenase (5-LO) and leukotriene A(4) hydrolase (LTA(4)H), is a pro-inflammatory mediator implicated in the pathogenesis of inflammatory bowel disease. However, inhibitors of 5-LO have not proved to be consistent in their therapeutic efficacy in colitis. Another approach to inhibiting LTB(4) synthesis is through the use of inhibitors of LTA(4)H, such as the novel, potent and selective compound, JNJ 26993135.Experimental Approach: The effect of oral administration of JNJ 26993135 has been evaluated in a rat model of colitis provoked by colonic instillation of trinitrobenzenesulphonic acid (TNBS). The extent and severity of the macroscopic inflammatory response, the colonic levels of myeloperoxidase (MPO) and LTB(4) and of the pro-inflammatory cytokines, tumour necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) were measured.Key Results: Oral administration of JNJ 26993135 (5, 15 and 30 mg kg(-1), twice a day) dose-dependently reduced both the extent and intensity of the colonic inflammatory damage observed 3 days after TNBS challenge. JNJ 26993135 also dose-dependently reduced the elevated colonic levels of LTB(4), as well as the inflammatory biomarkers, MPO, IL-6 and TNF-alpha. This dosing regimen was supported by the pharmacokinetic profile of JNJ 26993135, along with the demonstration of the inhibition of ex vivo production of LTB(4) in whole blood following oral administration.Conclusions and Implications: These results with JNJ 26993135 in the rat TNBS model support the role of LTB(4) in colitis and the potential value of targeting LTA(4)H for the treatment of inflammatory bowel diseases. [ABSTRACT FROM AUTHOR]

Background and Purpose: Interleukin (IL)-1 is a key mediator of inflammatory and host defence responses and its effects in the brain are mediated primarily via effects on glia. IL-1 induces release of inflammatory mediators such as IL-6 from glia via the type-1 receptor (IL-1R1) and established signalling mechanisms including mitogen-activated protein kinases and nuclear factor kappa-B. IL-1 also modifies physiological functions via actions on neurones, through activation of the neutral sphingomyelinase (nSMase)/Src kinase signalling pathway, although the mechanism of IL-1-induced IL-6 synthesis in neurones remains unknown.Experimental Approach: Primary mouse neuronal cell cultures, ELISA, Western blot and immunocytochemistry techniques were used.Key Results: We show here that IL-1beta induces the synthesis of IL-6 in primary mouse neuronal cultures, and this is dependent on the activation of IL-1R1, nSMase and Src kinase. We demonstrate that IL-1beta-induced Src kinase activation triggers the phosphorylation of the NMDA receptor NR2B subunit, leading to activation of Ca(2+)/calmodulin-dependent protein kinase II (CamKII) and the nuclear transcription factor CREB. We also show that NR2B, CamKII and CREB are essential signalling elements involved in IL-1beta-induced IL-6 synthesis in neurones.Conclusions and Implications: These results demonstrate that IL-1 interacts with the same receptors on neurones and glia to elicit IL-6 release, but does so via distinct signalling pathways. The mechanism by which IL-1beta induces IL-6 synthesis in neurones could be critical in both physiological and pathophysiological actions of IL-1beta, and may provide a new therapeutic target for the treatment of acute CNS injury. [ABSTRACT FROM AUTHOR]

Background and Purpose: Our aim was to examine the effect of demethylnobiletin on various experimental models of delayed-type hypersensitivity (DTH) reactions and to determine its influence on the mediators and enzymes involved in these reactions.Experimental Approach: DTH was induced in mice by oxazolone, dinitrofluorobenzene (DNFB) and sheep red blood cells (SRBC). The effect of demethylnobiletin on the ensuing DTH was studied, especially in relation to oedema formation, cell infiltration and tissue damage. Its activity on different mediators implicated in DTH reactions was also determined and its effect on nitric oxide synthase (NOS)-2 analysed. Finally, its influence on T lymphocyte proliferation, apoptosis and caspase 3 activity was tested.Key Results: DTH reactions were all reduced by demethylnobiletin. The experimental results suggest that the compound may act by reducing cell infiltration and by suppressing mediators such as interleukin-2 (IC50=1.63 microM), interleukin-4 (IC50=2.76 microM), tumour necrosis factor-alpha (IC50=0.66 microM), interferon-gamma (IC50=1.35 microM), and interleukin-1 beta (46% at 2.5 microM) and by concomitantly increasing the production of the anti-inflammatory cytokine, interleukin-10. In addition, while demethylnobiletin affected nitric oxide production, it did not modify NOS-2 expression. Finally, demethylnobiletin inhibited proliferation of T cells and induced their apoptosis.Conclusions and Implications: Demethylnobiletin decreased DTH reactions induced by various agents. This finding, along with the fact that the compound has a low toxicity and exhibits several other interesting properties, could pave the way for other structurally related citroflavonoids to be used as pharmacological agents in complementary therapies. [ABSTRACT FROM AUTHOR]

Background and purpose:The mortality associated with acute pancreatitis (AP) is largely attributable to abnormalities that occur in distant organs and supportive care remains the only treatment for patients with these complications. Recently, prophylactic pharmacological blockade of poly(ADP-ribose) polymerase (PARP) enzymes has been shown to attenuate the severity of the disease. However, the clinical relevance of PARP inhibitors administered after the onset of AP remains uncertain. The aim of the present study was to investigate the therapeutic effects of PARP inhibitors in established AP.Experimental approach:Mice were fed a choline/methionine-deficient/ethionine-supplemented (CMDE) diet to induce AP. PARP inhibitors were given at 36 h after the onset of CMDE diet. Severity of pancreatitis was assessed by measurements of serum amylase, lipase, IL-1β and IL-6, and histological grading. Serum hepatic enzymes, myeloperoxidase (MPO) activity and morphological changes were measured as indicators of hepatic insult. Lung injury was evaluated by MPO activity and morphological changes. Survival rates of mice were monitored for 7 days.Key results:CMDE diet administration resulted in a significant increase in serum amylase, lipase, IL-1β, IL-6, alanine aminotransferase and aspartate aminotranferase levels, indicating AP and associated liver injury. Analysis of the histopathological changes in pancreas, liver and lung revealed extensive tissue damage. Treatment of mice with PARP-inhibitors after the onset of AP was associated with a reduction in the severity of AP and, accordingly, with a reduced mortality rate.Conclusions and Implications:Our results support the therapeutic application of PARP inhibitors in the treatment of established AP.British Journal of Pharmacology (2007) 151, 998–1005; doi:10.1038/sj.bjp.0707310; published online 29 May 2007 [ABSTRACT FROM AUTHOR]

Background and purpose:We investigated expression of cannabinoid receptors and the effects of the endogenous cannabinoid virodhamine and the synthetic agonist CP55,940 on cAMP accumulation and interleukin-8 (IL-8) release in human bronchial epithelial cells.Experimental approach:Human bronchial epithelial (16HBE14o-) cells were used. Total mRNA was isolated and cannabinoid receptor mRNAs were detected by RT-PCR. Expression of CB1 and CB2 receptor proteins was detected with Western blotting using receptor-specific antibodies. cAMP accumulation was measured by competitive radioligand binding assay. IL-8 release was measured by ELISA.Key results:CB1 and CB2 receptor mRNAs and proteins were found. Both agonists concentration-dependently decreased forskolin-induced cAMP accumulation. This effect was inhibited by the CB2 receptor antagonist SR144528, and was sensitive to Pertussis toxin (PTX), suggesting the involvement of CB2 receptors and Gi/o-proteins. Cell pretreatment with PTX unmasked a stimulatory component, which was blocked by the CB1 receptor antagonist SR141716A. CB2 receptor-mediated inhibition of cAMP production by virodhamine and CP55,940 was paralleled by inhibition of tumor necrosis factor-α (TNF-α) induced IL-8 release. This inhibition was insensitive to SR141716A. In the absence of agonist, SR144528 by itself reduced TNF-α induced IL-8 release.Conclusions and implications:Our results show for the first time that 16HBE14o− cells respond to virodhamine and CP55,940. CB1 and CB2 receptor subtypes mediated activation and inhibition of adenylyl cyclase, respectively. Stimulation of the dominant CB2 receptor signalling pathway diminished cAMP accumulation and TNF-α-induced IL-8 release. These observations may imply that cannabinoids exert anti-inflammatory properties in airways by modulating cytokine release.British Journal of Pharmacology (2007) 151, 1041–1048; doi:10.1038/sj.bjp.0707320; published online 11 June 2007 [ABSTRACT FROM AUTHOR]

Background and purpose:Kinins have an important role in inflammatory cystitis and in animal pathophysiological models, by acting on epithelium, fibroblasts, sensory innervation and smooth muscle. The aim of this study was to characterize the receptors responsible for direct motor responses induced by kinins on human detrusor.Experimental approach:Human detrusor cells from biopsies were isolated and mantained in culture. B1 and B2 kinin receptors were characterized by means of radioligand and functional experiments (PI accumulation and PGE2 release).Key results:[3H]-[desArg9]-Lys-BK and [3H]-BK saturation studies indicated receptor density (Bmax) and K d values of 19 or 113 fmol mg−1, and 0.16 or 0.11 nM for the B1 or B2 receptors, respectively. Inhibition binding studies indicated the selectivity of the B1 receptor antagonist [desArg9Leu8]-Lys-BK and of the B2 receptor antagonists Icatibant and MEN16132. [DesArg9]-Lys-BK and BK induced PI accumulation with an EC50 of 1.6 and 1.4 nM and different maximal responses (Emax of [desArg9]-Lys-BK was 10% of BK). BK also induced prostaglandin E2 release (EC50 2.3 nM), whereas no response was detected with the B1 receptor agonist. The incubation of detrusor smooth muscle cells with interleukin 1β (IL-1β) or tumour necrosis factor-α (TNF-α) (10 ng ml−1) induced a time-dependent increase in radioligand-specific binding, which was greater for the B1 than for the B2 receptor.Conclusions and Implications:Human detrusor smooth muscle cells in culture retain kinin receptors, and represent a suitable model to investigate the mechanisms and changes that occur under chronic inflammatory conditions.British Journal of Pharmacology (2007) 150, 192–199. doi:10.1038/sj.bjp.0706976; published online 18 December 2006 [ABSTRACT FROM AUTHOR]

Background and Purpose: Macrophages release cytokines that may contribute to pulmonary inflammation in conditions such as chronic obstructive pulmonary disease. Thus, inhibition of macrophage cytokine production may have therapeutic benefit. p38 MAPK may regulate cytokine production, therefore, the effect of two p38 MAPK inhibitors, SB239063 and SD-282, on the release of TNF-alpha, GM-CSF and IL-8 from human macrophages was investigated.Experimental Approach: Cytokine release was measured by ELISA. Immunoblots and mRNA expression studies were performed to confirm p38 MAPK isoform expression and activity. Macrophages were isolated from lung tissue of current smokers, ex-smokers and emphysema patients and exposed to lipopolysaccharide. These cells then released cytokines in a concentration-dependent manner.Key Results: SB239063 only inhibited TNF-alpha release (EC50 0.3 +/- 0.1 microM). Disease status had no effect on the efficacy of SB239063. SD-282 inhibited both TNF-alpha and GM-CSF release from macrophages (EC50 6.1 +/- 1.4 nM and 1.8 +/- 0.6 microM respectively) but had no effect on IL-8 release. In contrast, both inhibitors suppressed cytokine production in monocytes.Conclusions and Implications: The differential effects of p38 MAPK inhibitors between macrophages and monocytes could not be explained by differences in p38 MAPK isoform expression or activity. However, the stability of TNF-alpha mRNA was significantly increased in macrophages compared to monocytes. These data suggest a differential involvement for p38 MAPK in macrophage cytokine production compared with monocytes. These effects are not due to lack of p38 activation or p38alpha expression in macrophages but may reflect differential effects on the stability of cytokine mRNA. [ABSTRACT FROM AUTHOR]

The role of the anti-inflammatory protein annexin-A1 (Anx-A1) in the phagocytic process has been investigated using a murine bone marrow culture-derived macrophage model from Anx-A1(+/+) and Anx-A1(-/-) mice. Macrophages prepared from Anx-A1(-/-) mice exhibited a reduced ingestion of zymosan, Neisseria meningitidis or sheep red blood cells, when compared to Anx-A1(+/+) cells and in the case of zymosan this effect was also mirrored by a reduced clearance in vivo when particles were injected into the peritoneal cavity of Anx-A1(-/-) mice. The ablation of the Anx-A1 gene did not cause any apparent cytoskeletal defects associated with particle ingestion but the cell surface expression of the key adhesion molecule CD11b was depressed in the Anx-A1(-/-) cells providing a possible explanation for the attenuated phagocytic potential of these cells. The production of the cytokines TNFalpha and IL-6 was increased in Anx-A1(-/-) macrophages following phagocytosis of all types of particle. [ABSTRACT FROM AUTHOR]