Physiological basis for novel drug therapies used to treat the inflammatory bowel diseases. I. Immunology and therapeutic potential of antiadhesion molecule therapy in inflammatory bowel disease

The Fully human anti-CD47 antibody SRF231 exerts dual-mechanism antitumor activity via engagement of the activating receptor CD32a

Background

CD47 is a broadly expressed cell surface glycoprotein associated with immune evasion. Interaction with the inhibitory receptor signal regulatory protein alpha (SIRPα), primarily expressed on myeloid cells, normally serves to restrict effector function (eg, phagocytosis and immune cell homeostasis). CD47/SIRPα antagonists, commonly referred to as ‘macrophage checkpoint’ inhibitors, are being developed as cancer interventions. SRF231 is an investigational fully human IgG₄ anti-CD47 antibody that is currently under evaluation in a phase 1 clinical trial. The development and preclinical characterization of SRF231 are reported here.

Methods

SRF231 was characterized in assays designed to probe CD47/SIRPα blocking potential and effects on red blood cell (RBC) phagocytosis and agglutination. Additionally, SRF231-mediated phagocytosis and cell death were assessed in macrophage:tumor cell in vitro coculture systems. Further mechanistic studies were conducted within these coculture systems to ascertain the dependency of SRF231-mediated antitumor activity on Fc receptor engagement vs CD47/SIRPα blockade. In vivo, SRF231 was evaluated in a variety of hematologic xenograft models, and the mechanism of antitumor activity was assessed using cytokine and macrophage infiltration analyses following SRF231 treatment.

Results

SRF231 binds CD47 and disrupts the CD47/SIRPα interaction without causing hemagglutination or RBC phagocytosis. SRF231 exerts antitumor activity in vitro through both phagocytosis and cell death in a manner dependent on the activating Fc-gamma receptor (FcγR), CD32a. Through its Fc domain, SRF231 engagement with macrophage-derived CD32a serves dual purposes by eliciting FcγR-mediated phagocytosis of cancer cells and acting as a scaffold to drive CD47-mediated death signaling into tumor cells. Robust antitumor activity occurs across multiple hematologic xenograft models either as a single agent or in combination with rituximab. In tumor-bearing mice, SRF231 increases tumor macrophage infiltration and induction of the macrophage cytokines, mouse chemoattractant protein 1 and macrophage inflammatory protein 1 alpha. Macrophage depletion results in diminished SRF231 antitumor activity, underscoring a mechanistic role for macrophage engagement by SRF231.

Conclusion

SRF231 elicits antitumor activity via apoptosis and phagocytosis involving macrophage engagement in a manner dependent on the FcγR, CD32a.

Immunomodulatory Effect of Urine-derived Stem Cells on Inflammatory Bowel Diseases via Downregulating Th1/Th17 Immune Responses in a PGE2-dependent Manner

BACKGROUND AND AIMS

Despite the therapeutic promise of stem cell therapy in the treatment of inflammatory bowel diseases [IBD], most donor cell populations have to be obtained via invasive approaches and often remain insufficiently validated. Urine-derived stem cells [USC] were recently shown to have regenerative properties and can be harvested in a safe, low-cost, and noninvasive way. This study aims to evaluate the immunomodulatory effect of USC and their efficacy in the management of IBD.

METHODS

Human USC were isolated and expanded from the urine of healthy male adult volunteers [n = 3, age range 24-30 years]. USC were characterised by cell surface marker expression profile and multipotent differentiation. The in vitro immunomodulatory effect of USC was evaluated by co-culturing with human CD4+ T cells upon stimulation with phytohaemagglutinin [PHA]. The proliferation of CD4+ T was measured by fluorescence-activated cell sorting [FACS]. Cytokine array and quantitative real-time polymerase chain reaction [RT-PCR] were applied to examine cytokine levels. In vivo therapeutic value of USC was assessed using a murine colitis model induced by dextran sulphate sodium [DSS] or 2, 4, 6-trinitrobenzene sulphonic acid [TNBS]. The immunomodulatory effect of USC and bone marrow-derived mesenchymal stem cells [BMSC] was compared when co-cultured with CD4+ T cells. The therapeutic efficacy of USC and BMSC on IBD was compared when administered in an acute DSS model in vivo.

RESULTS

USC were positive for mesenchymal stem cell markers but were negative for haematopoietic stem cell markers. These cells differentiated into osteo-, adipo-, and chondrogenic cell lineages. Similar to BMSC, the proliferation of CD4+ T cells was significantly inhibited when co-cultured with USC, as a consequence of Th1/Th17 immune response inhibition. Systemic administration of USC significantly ameliorated the clinical and histopathological severity of colitis and increased the survival rate in both acute and chronic murine colitis models. Moreover, implantation of USC led to downregulation of the Th1/Th17 immune responses in a PGE2-dependent manner.

CONCLUSIONS

This study demonstrated that implantation of USC reduces inflammation in an IBD rodent model via downregulation of Th1/Th17 immune responses, indicating that USC therapy serves as a potential cell-based therapeutic candidate treatment for IBD.

Ro60 Inhibits Colonic Inflammation and Fibrosis in a Mouse Model of Dextran Sulfate Sodium-Induced Colitis

Inflammatory bowel disease (IBD) is caused by chronic inflammation of the gastrointestinal tract. The pathogenesis of IBD remains unclear. The inflammation is associated with activation of T helper (Th) lymphocytes and chronic production of inflammatory cytokines. Ro60 suppresses the expression of tumor necrosis factor α, interleukin (IL)-6, and interferon α by inhibiting Alu transcription; control of Ro60 mRNA expression may thus be therapeutically useful. However, few studies have evaluated the anti-inflammatory activity of Ro60. The Ro60 level is decreased in IBD patients; we thus hypothesized that Ro60 was involved in the development of this autoimmune disease. We subjected mice with dextran sodium sulfate (DSS)-induced colitis to gene therapy using a vector that overexpressed Ro60 threefold. We scored IBD progression by repeatedly weighing the mice. Ro60 ameliorated colitis severity and reduced the levels of tumor necrosis factor α, IL-6, IL-17, IL-8, and vascular endothelial growth factor. Ro60 overexpression decreased the levels of α-smooth muscle actin (a marker of activated myofibroblasts) and type I collagen. The anti-inflammatory and anti-fibrotic activities of Ro60 ameliorated the severity of DSS-induced colitis in mice by repressing inflammation, fibrosis, angiogenesis, and the production of reactive oxygen species.

Profoundly Expanded T-cell Clones in the Inflamed and Uninflamed Intestine of Patients With Crohn's Disease

BACKGROUND AND AIM

T cells are key players in the chronic intestinal inflammation that characterises Crohn's disease. Here we aim to map the intestinal T-cell receptor [TCR] repertoire in patients with Crohn's disease, using next-generation sequencing technology to examine the clonality of the T-cell compartment in relation to mucosal inflammation and response to therapy.

METHODS

Biopsies were taken from endoscopically inflamed and uninflamed ileum and colon of 19 patients with Crohn's disease. From this cohort, additional biopsies were taken after 8 weeks of remission induction therapy from eight responders and eight non-responders. Control biopsies from 11 patients without inflammatory bowel disease [IBD] were included. The TCRβ repertoire was analysed by next-generation sequencing of biopsy RNA.

RESULTS

Both in Crohn's disease patients and in non-IBD controls, a broad intestinal T-cell repertoire was found, with a considerable part consisting of expanded clones. Clones in Crohn's disease were more expanded [p = 0.008], with the largest clones representing up to as much as 58% of the total repertoire. There was a substantial overlap of the repertoire between inflamed and uninflamed tissue and between ileum and colon. Following therapy, responders showed larger changes in the T-cell repertoire than non-responders, although a considerable part of the repertoire remained unchanged in both groups.

CONCLUSIONS

The intestinal T-cell repertoire distribution in Crohn's disease is different from that in the normal gut, containing profoundly expanded T-cell clones that take up a large part of the repertoire. The T-cell repertoire is fairly stable regardless of endoscopic mucosal inflammation or response to therapy.

The Role of the Mesentery in Crohn's Disease: The Contributions of Nerves, Vessels, Lymphatics, and Fat to the Pathogenesis and Disease Course

Crohn's disease (CD) is a complex gastrointestinal disorder involving multiple levels of cross talk between the immunological, neural, vascular, and endocrine systems. The current dominant theory in CD is based on the unidirectional axis of dysbiosis-innate immunity-adaptive immunity-mesentery-body system. Emerging clinical evidence strongly suggests that the axis be bidirectional. The morphologic and/or functional abnormalities in the mesenteric structures likely contribute to the disease progression of CD, to a less extent the disease initiation. In addition to adipocytes, mesentery contains nerves, blood vessels, lymphatics, stromal cells, and fibroblasts. By the secretion of adipokines that have endocrine functions, the mesenteric fat tissue exerts its activity in immunomodulation mainly through response to afferent signals, neuropeptides, and functional cytokines. Mesenteric nerves are involved in the pathogenesis and prognosis of CD mainly through neuropeptides. In addition to angiogenesis observed in CD, lymphatic obstruction, remodeling, and impaired contraction maybe a cause and consequence of CD. Lymphangiogenesis and angiogenesis play a concomitant role in the progress of chronic intestinal inflammation. Finally, the interaction between neuropeptides, adipokines, and vascular and lymphatic endothelia leads to adipose tissue remodeling, which makes the mesentery an active participator, not a bystander, in the disease initiation and precipitation CD. The identification of the role of mesentery, including the structure and function of mesenteric nerves, vessels, lymphatics, and fat, in the intestinal inflammation in CD has important implications in understanding its pathogenesis and clinical management.

beta-Naphthoflavone protects from peritonitis by reducing TNF-alpha-induced endothelial cell activation

β-Naphthoflavone (β-NF), a ligand of the aryl hydrocarbon receptor, has been shown to possess anti-oxidative properties. We investigated the anti-oxidative and anti-inflammatory potential of β-NF in human microvascular endothelial cells treated with tumor necrosis factor-alpha (TNF-α). Pretreatment with β-NF significantly inhibited TNF-α-induced intracellular reactive oxygen species, translocation of p67(phox), and TNF-α-induced monocyte binding and transmigration. In addition, β-NF significantly inhibited TNF-α-induced ICAM-1 and VCAM-1 expression. The mRNA expression levels of the inflammatory cytokines TNF-α and IL-6 were reduced by β-NF, as was the infiltration of white blood cells, in a peritonitis model. The inhibition of adhesion molecules was associated with suppressed nuclear translocation of NF-κB p65 and Akt, and suppressed phosphorylation of ERK1/2 and p38. The translocation of Egr-1, a downstream transcription factor involved in the MEK-ERK signaling pathway, was suppressed by β-NF treatment. Our findings show that β-NF inhibits TNF-α-induced NF-kB and ERK1/2 activation and ROS generation, thereby suppressing the expression of adhesion molecules. This results in reduced adhesion and transmigration of leukocytes in vitro and prevents the infiltration of leukocytes in a peritonitis model. Our findings also suggest that β-NF might prevent TNF-α-induced inflammation.

Integrin antagonists are effective and safe for Crohn’s disease: A meta-analysis

AIM: To evaluate the efficacy and safety of integrin antagonists, including natalizumab and vedolizumab, in Crohn’s disease (CD).

METHODS: We carried out a literature search in PubMed, MEDLINE, EMBASE and the Cochrane Library to screen for citations from January 1990 to August 2014. Data analysis was performed using Review Manager version 5.2.

RESULTS: A total of 1340 patients from five studies were involved in this meta-analysis. During 6-12 wk treatment, integrin antagonists increased the rate of clinical response and remission with OR = 1.69, 95%CI: 1.37-2.09 and 1.84, 95%CI: 1.44-2.34, respectively. No significant difference was found between integrin antagonists and placebo treatments regarding their adverse reactions (OR = 1.07, 95%CI: 0.83-1.38) and serious adverse reactions (OR = 0.81, 95%CI: 0.57-1.15).

CONCLUSION: The results prove the efficacy and safety of integrin antagonists for CD treatment, although the treatment strategies varied.

Biological therapy for ulcerative colitis

Ulcerative colitis (UC) is a major form of inflammatory bowel disease (IBD) worldwide. Better understanding of the pathogenesis of UC has led to the development of novel therapeutic agents that target specific mediators of the inflammatory cascade. A number of biological agents have been approved by the U.S. Food and Drug Administration (FDA) for the treatment of UC and several more are currently in various phases of drug development. The commonly used agents include TNFα antagonists (e.g. infliximab, adalimumab, and golimumab) and anti-integrin agents (vedolizumab). These biological agents have profoundly influenced the management of UC patients, especially those with refractory disease. This paper reviews the currently available knowledge and evidence for the use of various biological agents in the treatment of UC.

Role of vitamin D derivatives in intestinal tissue of patients with inflammatory bowel diseases

BACKGROUND AND AIM

The adhesion molecule expression and matrix metalloproteinases (MMPs) are proposed to be major factors for intestinal injury mediated by T cells in (IBD) and are up-regulated in intestinal mucosa of IBD patients. To investigate the effect of vitamin D derivatives on adhesion molecules and MMPs in colonic biopsies of IBD patients.

METHODS

Biopsies from inflamed and non-inflamed tract of terminal ileum and colon and PBMC from the same IBD patients were cultured with or without vitamin D derivatives. MMP activity and adhesion molecule levels were determined.

RESULTS

1,25(OH)2D3 and ZK 191784 significantly decrease ICAM-1 protein levels in the biopsies obtained only from the inflamed region of intestine of UC patients, while MAdCAM-1 levels decrease in the presence of 1,25(OH)2D3 in the non-inflamed region, and, in the presence of ZK, in the inflamed one. In CD patients 1,25(OH)2D3 and ZK decrease ICAM-1 and MAdCAM-1 in the biopsies obtained from the non-inflamed and inflamed regions, with the exception of ICAM-1 in the inflamed region in the presence of 1,25(OH)2D3. The expression of MMP-9, MMP-2, and MMP-3 decreases in the presence of vitamin D derivatives in UC and CD with the exception of 1,25(OH)2D3 that does not affect the levels of MMP-9 and MMP-2 in CD. Vitamin D derivatives always affect MMP-9, MMP-2 and ICAM-1 in PBMC of UC and CD patients.

CONCLUSIONS

Based on the increased expression of ICAM-1, MAdCAM-1 and MMP-2,-9,-3 in IBD, our study suggests that vitamin D derivatives may be effective in the management of these diseases.

Leukocyte traffic blockade as a therapeutic strategy in inflammatory bowel disease

Dysregulated recruitment of leukocytes into the intestine is a characteristic feature of IBD. Several families of molecules regulate the influx of these cells into sites of inflammation within the gastrointestinal tract. Pharmacological blockade of interactions between molecules that mediate the formation of stable bonds (integrins) and their endothelial ligands has already shown clinical efficacy. Antibodies that target participant molecules have been approved by the US Federal Drug Administration for use in Crohn's, multiple sclerosis (MS) (i.e. natalizumab) and psoriasis (i.e. efalizumab). A more recent additional family of drugs, which might also interfere with lymphocyte traffic (i.e. sphingosine-1- phosphate receptor agonists: fingolimod) is in clinical use for MS and just recently entered the clinical trial stage for ulcerative colitis. In the present review we discuss basic aspects of clinically relevant molecules and compile the clinical studies that support the targeting of specific steps of the leukocyte adhesion cascade for therapeutic purposes in IBD.

Is there a role for vedolizumab in the treatment of ulcerative colitis and Crohn's disease?

Inflammatory bowel disease (IBD) is an important cause of morbidity and mortality for millions of patients worldwide. Current treatment options include corticosteroids, 5-aminosalicylates, immunosuppressants, and TNFα antagonists. However, these are frequently ineffective in achieving sustained response and remission over time. At present, gastroenterologists lack safe and effective treatments if patients fail anti-TNF therapy. Vedolizumab is a promising new agent for IBD patients refractory to anti-TNF therapy. Vedolizumab is an integrin antagonist which is thought to act by reducing inflammation by selectively inhibiting leukocyte migration in the gut. Emerging evidence from clinical trials suggests a potential role for vedolizumab in both ulcerative colitis (UC) and Crohn's disease (CD), particularly in patients who have previously failed biological therapy. The safety profile of vedolizumab appears reasonable, possibly because it has a "gut-selective" mode of action, with no reported cases of progressive multifocal leukoencephalopathy, a condition which has been linked to another integrin antagonist, natalizumab. This review discusses the available evidence for integrin antagonists and their potential role in the management of IBD.

Review article: anti-adhesion therapies for inflammatory bowel disease

BACKGROUND

A high proportion of patients with inflammatory bowel disease (IBD) do not achieve clinical remission with the current therapies including mesalazine (mesalamine), immunossupresants (IMS) and antibodies against tumour necrosis factor (anti-TNF). Moreover, IMS and anti-TNF involve a nonnegligible risk for infections and/or malignancies. The anti-adhesion molecules are one of the most interesting new treatments because of their gut-selectivity.

AIM

To review the physiopathology of the adhesion molecules and the current drugs targeting this mechanism.

METHODS

We performed a literature review in PubMed and in clinicaltrials.gov using the terms 'anti-adhesion molecules', 'inflammatory bowel disease', 'natalizumab', 'vedolizumab', 'AMG181', 'Etrolizumab', 'PF-00547659', 'AJM300', 'Alicaforsen' and 'CCX282-B' up to November 2013.

RESULTS

A total of eight drugs were found including those targeting the α4β1, α4β7 or αEβ7 integrins as well as the ICAM-1 and MAdCAM-1 addressins and the chemokine receptor 9. The rationale for these drugs is the blockade of gut-homing T lymphocytes and the ones targeting the α4β7/MAdCAM-1 interaction presented the most promising results in luminal disease. Vedolizumab, an α4β7 antibody, has completed phase 3 trials with very positive results especially for ulcerative colitis. However, many questions remain unanswered such as the effect of these therapies in perianal disease and extraintestinal manifestations.

CONCLUSIONS

The blockade of the α4β7/MAdCAM-1 interaction and especially vedolizumab is an effective and safe gut-specific treatment for IBD. Further studies are needed to clarify the efficacy and safety of the other anti-adhesion drugs and to define the specific indications of these therapies in the different scenarios of IBD.

Investigation of intercellular adhesion molecules (ICAMs) gene expressions in patients with Barrett's esophagus

The adhesion molecules play a major role in inflammation as well as in neoplastic diseases. The aim of this study is to evaluate the expressions of the adhesion molecules, intercellular adhesion molecule 1 (ICAM-1), ICAM-2, and ICAM-3, in Barrett's esophagus, recognized as a premalign lesion for esophageal cancer and related to inflammation. Eighteen patients with Barrett's esophagus according to endoscopy and 25 volunteers without Barrett's esophagus disease were included in the study. Tissue samples were supplied by biopsy and used for both gene expression and immunohistochemical analysis. The significance of the differences between the two groups was assessed by Student's t test. The ICAM-1 expression level was fivefold higher in the patient group compared with that of the control. There was an increase in the serum level of ICAM-1 in patients compared to that of the controls, but this increase was not significant. ICAM-2 levels were also increased in the patient group, but it was not significant. There was no difference between controls and patients in ICAM-3 levels. Significantly higher levels of ICAM-1 gene expression make us think that ICAM-1 may play an important role in Barrett's esophagus. We think that more studies, with larger patient groups and preferably detailed histopathological and clinical evaluations, are needed to explain the severity of ICAM-1, ICAM-2, and ICAM-3 molecules in Barrett's esophagus.

Inhibition of selective adhesion molecules in treatment of inflammatory bowel disease

Lymphocyte infiltration into the intestinal tract in inflammatory bowel disease (IBD) is mediated by interaction between α4 integrin and its specific ligands. Development of monoclonal antibodies against α4 integrin allowed targeting of lymphocyte trafficking into the intestine as a novel therapeutic intervention. Natalizumab, vedolizumab, alicaforsen AJM300, rhuMAb β7, CCX282-B, and PF-00547,659 are few of monoclonal antibodies that have shown high promise in trials with the potential for more attractive benefit:risk ratio than currently available therapies. In this review, an attempt is made to underline the therapeutic potential and the safety of anti-adhesion molecule treatment in IBD.

Ultrasound-based molecular imaging and specific gene delivery to mesenteric vasculature by endothelial adhesion molecule targeted microbubbles in a mouse model of Crohn's disease

Crohn's disease (CD) is a chronic inflammatory disorder of the gastrointestinal tract (GI) for which treatments with immunosuppressive drugs have significant side-effects. Consequently, there is a clinical need for site-specific and non-toxic delivery of therapeutic genes or drugs for CD and related disorders such as inflammatory bowel disease. The aim of this study was to validate a gene delivery platform based on ultrasound-activated lipid-shelled microbubbles (MBs) targeted to inflamed mesenteric endothelium in the CD-like TNFΔARE mouse model. MBs bearing luciferase plasmid were functionalized with antibodies to MAdCAM-1 (MB-M) or VCAM-1 (MB-V), biomarkers of gut endothelial cell inflammation and evaluated in an in vitro flow chamber assay with appropriate ligands to confirm targeting specificity. Following MB retro-orbital injection in TNFΔARE mice, the mean contrast intensity in the ileocecal region from accumulated MB-M and MB-V was 8.5-fold and 3.6-fold greater, respectively, compared to MB-C. Delivery of luciferase plasmid to the GI tract in TNFΔARE mice was achieved by insonating the endothelial cell-bound agents using a commercial sonoporator. Luciferase expression in the midgut was detected 48 h later by bioluminescence imaging and further confirmed by immunohistochemical staining. The liver, spleen, heart, and kidney had no detectable bioluminescence following insonation. Transfection of the microcirculation guided by a targeted, acoustically-activated platform such as an ultrasound contrast agent microbubble has the potential to be a minimally-invasive treatment strategy to ameliorate CD and other inflammatory conditions.

Current advantages in the application of proteomics in inflammatory bowel disease

Since the formulation of the concept of proteomics, a plethora of proteomic technologies have been developed in order to study proteomes. In inflammatory bowel disease (IBD), several studies use proteomics to try to better understand the disease and discover molecules which can be used as biomarkers. Biomarkers should be able to be used for diagnosis, therapy and prognosis. Although several biomarkers have been discovered, few biomarkers have clinical value. In this review, we analyze and report the current use of proteomic techniques to highlight biomarkers characterizing IBD, and different stages of disease activity. We also report the biomarkers and their potential clinical value.

Nitric oxide modifies chromatin to suppress ICAM-1 expression during colonic inflammation

Nitric oxide (NO) is an established inflammatory mediator. However, it remains controversial whether NO enhances the inflammatory response in the colon or suppresses it. We investigated the epigenetic regulation of Icam-1 expression by NO following induction of colonic inflammation in rats by 2,4,6-trinitrobenzene sulfonic (TNBS) acid and obtaining colonic muscularis externae tissues 24 h later. TNBS inflammation induced intercellular adhesion molecule-1 (ICAM-1) expression by translocating NF-κB to the nucleus. The incubation of inflamed tissues with S-nitrosoglutathione (GSNO) did not affect the nuclear translocation of NF-κB; however, it suppressed the NF-κB binding to DNA. Chromatin immunoprecipitation analysis (ChIP)-qPCR assays showed that the increase in NF-κB/DNA interaction following inflammation is due to the transcriptional downregulation of global HDAC3 and a decrease in its interaction with the DNA on the Icam-1 promoter containing the binding motifs of NF-κB. The decrease in the association of histone deacetylase (HDAC) 3 with the Icam-1 promoter increased the acetylation of histone 4 lysine residue 12 (H4K12), which would favor chromatin relaxation and greater access of NF-κB to its DNA binding sites. HDAC3 dissociation from the DNA did not affect the acetylation levels of H4K8 and H4K16. The NO release by GSNO countered the upregulation of Icam-1 by increasing the transcription of global HDAC3 and its association with the Icam-1 promoter, and by suppressing H4K12 acetylation. We conclude that chromatin modification by transcriptional downregulation of HDAC3 plays a critical role in the induction of the inflammatory response. NO may serve as an anti-inflammatory mediator during the acute stage of inflammation by blunting the downregulation of global HDAC3, increasing HDAC3 interaction with the nucleosomes containing the binding moieties of NF-κB, reducing H4K12Ac to restrict the access of NF-κB to DNA, and suppressing ICAM-1 expression.

Red wine polyphenolics reduce the expression of inflammation markers in human colon-derived CCD-18Co myofibroblast cells: potential role of microRNA-126

Chronic intestinal inflammation is an established risk factor for colon cancer. Polyphenolic compounds from fruit and vegetables have been shown to have anti-inflammatory properties in several cell lines and tissues. However, their anti-inflammatory mechanisms, involving microRNAs in the regulation of inflammation, have not been extensively investigated. The goal of this research was to assess the chemopreventive potential of polyphenolics extracted from red wine made with Lenoir grapes (Vitis aestivalis hybrid) in human colon-derived CCD-18Co myofibroblasts cells, and to assess the potential involvement of microRNA-126 (miR-126) in the underlying mechanisms. The results show that the polyphenolic red wine extract (WE) decreased mRNA expression of lipopolysaccharide (LPS)-induced inflammatory mediators NF-kB, ICAM-1, VCAM-1, and PECAM-1 by 1.95-, 1.98-, 1.52-, and 1.84-fold respectively, in a dose dependent manner (0-100 μg of gallic acid equivalent (GAE) mL(-1)) down to 0.80-, 0.79-, 0.66-, and 0.68-fold in DMSO-treated control cells not challenged with LPS, respectively. Correspondingly, miR-126, which has a target region within the 3'-UTR of VCAM-1 mRNA, was increased 2.79-fold by the WE at 100 μg GAE mL(-1). The potential role of miR-126 was confirmed by transfecting cells with a specific miR-126-antagomir, as-miR-126. Transfection with as-miR-126 down-regulated miR-126 to 0.71-fold in the control cells and up-regulated mRNA levels of NF-kB, ICAM-1, VCAM-1, and PECAM-1 to 1.80-, 1.49-, 2.30-, and 1.95-fold of controls, respectively. WE at 100 μg GAE mL(-1) partially reversed the effects of the as-miR-126 to 1.02-, 1.01-, 1.04-, and 1.05-fold, for mRNA levels of NF-kB, ICAM-1, VCAM-1, and PECAM-1 respectively. This indicates the potential role of miR-126 in the anti-inflammatory properties of polyphenolics from red wine in CCD-18Co myofibroblasts cells.

Role of high endothelial postcapillary venules and selected adhesion molecules in periodontal diseases: a review

Periodontitis is accompanied by the proliferation of small blood vessels in the gingival lamina propria. Specialized postcapillary venules, termed periodontal high endothelial-like venules, are also present, and demonstrate morphological and functional traits similar to those of high endothelial venules (HEVs) in lymphatic organs. The suggested role of HEVs in the pathogenesis of chronic periodontitis involves participation in leukocyte transendothelial migration and therefore proinflammatory effects appear. Recent observations suggest that chronic periodontitis is an independent risk factor for systemic vascular disease and may result in stimulation of the synthesis of acute phase protein by cytokines released by periodontal high endothelial cells (HECs). However, tissue expression of HEV-linked adhesion molecules has not been evaluated in the gingiva of patients with chronic periodontitis. This is significant in relation to potential therapy targeting expression of the adhesion molecules. In this review, current knowledge of HEV structure and the related expression of four surface adhesion molecules of HECs [CD34, platelet endothelial cell adhesion molecule 1, endoglin and intercellular adhesion molecule 1 (ICAM-1)], involved in the key steps of the adhesion cascade in periodontal diseases, are discussed. Most studies on the expression of adhesion molecules in the development and progression of periodontal diseases pertain to ICAM-1 (CD54). Studies by the authors demonstrated quantitatively similar expression of three of four selected surface markers in gingival HEVs of patients with chronic periodontitis and in HEVs of reactive lymph nodes, confirming morphological and functional similarity of HEVs in pathologically altered tissues with those in lymphoid tissues.

Met-enkephalins in patients with inflammatory bowel diseases

PURPOSE

Opioid peptides provide a link between the neuroendocrine and immune systems. They modify the inflammatory process through their effect on the synthesis and secretion of cytokines and on the proliferation of leukocytes to the inflammatory lesion. The evaluation analyzed changes in free met-enkephalin concentration values in the serum and colon mucosal biopsy specimens of patients with inflammatory bowel disease (IBD).

MATERIAL AND METHODS

In serum and colon mucosal biopsy specimens, free met-enkephalin levels were determined in 43 patients with ulcerative colitis (UC) and 38 individuals with Crohn's disease (CD). The evaluation analyzed the effect of disease activity, inflammatory lesions of the colon and laboratory parameters, on the level of the investigated marker. The control group consisted of 45 healthy volunteers.

RESULTS

Serum free met-enkephalin levels were depressed in patients with CD (85.4pg/ml) and UC (101.5pg/ml) as compared to the controls (119.4pg/ml). Met-enkephalin levels in colonic biopsies collected from inflammatory lesions in IBD patients were significantly higher as compared to sections without inflammatory lesions (6.59pg/mg vs. 2.89pg/mg, p < 0.01 in the CD group and 6.12pg/mg vs. 3.47pg/mg, p < 0.05 in the UC group) and their level correlated with disease activity.

CONCLUSIONS

The present investigation is the first study that demonstrates changes in free met-enkephalin levels in IBD that may play a role in the pathogenesis and course of the disease. Further studies are necessary to assess the anti-inflammatory effect of opioid peptides.

Suppression of LPS-induced inflammatory and NF-κB responses by anomalin in RAW 264.7 macrophages

The treatment of inflammatory diseases today is largely based on interrupting the synthesis or action of the mediators that drive the host's response to injury. It is on the basis of this concept that most of the anti-inflammatory drugs have been developed. In our continuous search for novel anti-inflammatory agents from traditional medicinal plants, Saposhnikovia divaricata has been a focus of our investigations. Anomalin, a pyranocoumarin constituent of S. divaricata, exhibits potent anti-inflammatory activity. To clarify the cellular signaling mechanisms underlying the anti-inflammatory action of anomalin, we investigated the effect of anomalin on the production of inflammatory molecules in LPS-stimulated murine macrophages. The anomalin dose-dependently inhibited inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) mRNA and protein expression in LPS-stimulated RAW 264.7 macrophage. Molecular analysis using quantitative real time polymerase chain reaction (qRT-PCR) revealed that several pro-inflammatory cytokines, including tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), were reduced by anomalin, and this reduction correlated with the down-regulation of the NF-κB signaling pathway. In addition, anomalin suppressed the LPS-induced phosphorylation and degradation of IκBα. To further study the mechanisms underlying its anti-inflammatory activity, an electrophoretic mobility shift assay (EMSA) using a (32) P-labeled NF-κB probe was conducted. LPS-induced NF-κB DNA binding was drastically abolished by anomalin. The present data suggest that anomalin is a major anti-inflammatory agent and may be a potential therapeutic candidate for the treatment of inflammatory disorders.

Protective effect of total alkaloids of Sophora alopecuroides on dextran sulfate sodium-induced chronic colitis

OBJECTIVE

To investigate the effect of total alkaloids of Sophora alopecuroides (TASA) on dextran sulfate sodium (DSS)-induced colitis in mice.

METHODS

Chronic experimental colitis was induced by administration of 4 cycles of 4% DSS. Fifty mice were randomly distributed into 4 groups (normal, DSS, DSS/high-dose TASA, and DSS/low-dose TASA groups) by a random number table with body weight stratification. Mice in the normal group (n=11) and DSS-induced colitis control group (n=15) received control treatment of 20 mL/kg distilled water; DSS plus TASA high- and low-dose groups (n=12 each) were treated with TASA solution (20 mL/kg) at the doses of 60 mg/kg and 30 mg/kg, respectively. The severity of colitis was assessed on the basis of clinical signs, colon length, and histology scores. Moreover, secretory immunoglobulin A (sIgA) and haptoglobin (HP) were analyzed by enzyme linked immunosorbent assay; intercellular adhesion molecule 1 (ICAM-1) and macrophage-migration inhibitory factor (MIF) gene expressions were analyzed by quantitative reverse transcriptase realtime polymerase chain reaction (qRT-PCR) using SYBA green I; and nuclear factor κ B (NF-κ B) expression and activation and p65 interaction with the promoter of ICAM-1 gene were assessed by Western blotting and chromatin immunoprecipitation assay.

RESULTS

TASA administration significantly attenuated the damage and substantially reduced HP elevation and maintained the level of cecum sIgA. TASA inhibited the ICAM-1 gene expression and had no effect on MIF gene expression. Also, TASA was able to reduce phospho-I κ B α (p-I κ B α) protein expression; however, it had no effect on the activation of I κ B kinase α (IKK α) and inhibitor of NF-κ B α (I κ B α). Moreover, TASA inhibited the p65 recruitment to the ICAM-1 gene promoter.

CONCLUSIONS

TASA had a protective effect on DSS-induced colitis. Such effect may be associated with its inhibition of NF-κ B activation and blockade of NF-κ B-regulated transcription activation of proinflammatory mediator gene.

2-Polyunsaturated acyl lysophosphatidylethanolamine attenuates inflammatory response in zymosan A-induced peritonitis in mice

In the present study, the anti-inflammatory action of lysophosphatidylethanolamine (lysoPtdEtn), orally administered, in zymosan A-induced peritonitis was examined. Oral administration of 2-DHA-lysoPtdEtn (ED(50), ~111 μg/kg) or 2-ARA-lysoPtdEtn (ED(50), 221 μg/kg) was found to inhibit the plasma leakage in mice treated with zymosan A. In support of this, 2-polyunsaturated acyl-lysoPtdEtn diminished the formation of LTC(4), a lipid mediator responsible for vascular permeability. Next, 2-DHA-lysoPtdEtn (ED(50), 110 μg/kg) or 2-ARA-lysoPtdEtn (ED(50), 123 μg/kg) effectively inhibited the leukocyte extravasation into the peritoneum. Consistent with this, each polyunsaturated-lysoPtdEtn diminished the formation of LTB(4) and 12-HETE, potent chemotactic factors. Additionally, the level of pro-inflammatory mediator (IL-1 β, IL-6, TNF-α or NO) was lowered remarkably in contrast to the augmentation of anti-inflammatory interleukin IL-10. Furthermore, 2-(15-HETE)-lysoPtdEtn and 2-(17-HDHE)-lysoPtdEtn, 15-lipoxygenation product of 2-ARA-lysoPtdEtn and 2-DHA-lysoPtdEtn, respectively, were more potent than corresponding lysoPtdEtn, suggesting the action of 2-acyl-lysoPtdEtn might be expressed through 15-lipoxygenation. In support of this, the formation of 15-HETE and LXA(4) was upgraded in accordance with an increasing dose of 2-ARA-lysoPtdEtn. Separately, anti-inflammatory actions, 2-polyunsaturated acyl-lysoPtdEtns also drastically diminished leukocyte infiltration in a later phase of zymosan A-induced peritonitis, indicating that these lipids also possess pro-resolving activity. Taken together, it is suggested that polyunsaturated lysoPtdEtns and their lipoxygenation derivatives, could be classified as potent anti-inflammatory lipids.

New and emerging biologics in the treatment of inflammatory bowel disease: quo vadis?

Inflammatory bowel diseases (IBD) are pathological conditions characterized by chronic inflammation that is primarily the consequence of dysregulation of the immune response. Over the last decade, the advances in the pathophysiology of IBD have paved the way for the development of a number of biological agents that selectively target specific molecules and/or pathways involved in gut inflammation. Although numerous, so far, the only biological therapeutics that are approved for the treatment for IBD are monoclonal antibodies against tumor necrosis factor alpha. This paper systematically reviews the mechanismof-action, efficacy, short-term and, where available, long-term safety of biological agents that target molecules other than tumor necrosis factor alpha, in IBD.

Amelioration of dextran sulfate sodium-induced chronic colitis by sulfasalazine salicylazosulfapyridine via reducing NF-kappaB transcription factor p65 recruitment to ICAM-1 gene promoters

Sulfasalazine salicylazosulfapyridine (SASP), consisting of 5-aminosalicylic acid bound to sulfapyridine by a diazo bond, is an effective drug in the treatment of inflammatory bowel diseases (IBD). However, its mechanism of action remains a matter of debate. The objective of our work was to investigate SASP's effect on NF-kappaB signal transduction pathway in transcriptional regulation level. Repeated colitis was induced by administration of 4 cycles of 4% dextran sulfate sodium (DSS); The severity of colitis was assessed on the basis of clinical signs, colon length, and histology scores. Moreover, sIgA and haptoglobin (HP) were analyzed by enzyme linked immunosorbent assay, and ICAM-1 gene expression was analyzed by quantitative reverse transcriptase real-time polymerase chain reaction (qRT-PCR) using SYBA green I. NF-kappaB signal transduction proteins and transcriptional factor p65 interaction with promoter of ICAM-1 were assessed by western blotting and chromatin immunoprecipitation assay. SASP administration significantly attenuated the colitis signs and caused substantial reductions of HP expression, and maintained the level of cecum sIgA. SASP inhibited ICAM-1 gene expression and had no effect on MIF gene expression. Also, SASP was able to reduce p-IkBalpha protein expression; however, no change in the activation of IKKalpha, IKKbeta, p65, and IKBalpha was noted. SASP inhibited p65 recruitment to the gene ICAM-1 promoter. In conclusion, inhibition of NF-kappaB pathway signal proteins and blockade of p65 binding to gene ICAM-1 promoter might explain the effect and mechanisms of SASP at alleviating DSS-induced colitis in mice.

Effect of sophoridine on dextran sulfate sodium-induced colitis in C57BL/6 mice

Sophoridine (SRI), one of the quinolizidine alkaloids, is a new anticancer drug with noticeable antitumor action and lower toxicity. To our knowledge, there is no report about its effect on colitis. Repeated colitis was induced by administration of four cycles of 4% DSS. The severity of colitis was assessed on the basis of clinical signs, colon length and histology scores. Moreover, cecum secretory immunoglobulin A (sIgA) and plasma haptoglobin (HP) were analyzed by enzyme-linked immunosorbent assay and ICAM-1, and macrophage migration inhibitory factor (MIF) gene expression was analyzed by quantitative reverse transcriptase real-time polymerase chain reaction using SYBR Green I. SRI administration significantly attenuated the damage and caused substantial reduction of the rise in plasma HP, and maintained the level of cecum sIgA. SRI inhibited the ICAM-1 gene expression and had no effect on MIF gene expression. In conclusion, for the first time, the activity of SRI on DSS-induced colitis mice was investigated, which suggests that SRI could be an attractive therapeutic option in the treatment of inflammatory bowel disease.

Anti-adhesion molecule therapy for inflammatory bowel disease

Although biologic agents directed against tumor necrosis factor alpha (TNFα) continue to be an effective therapeutic strategy for patients with inflammatory bowel disease (IBD), approximately 30% of patients with Crohn's disease (CD) who are refractory to standard treatment do not respond to induction therapy with TNFα inhibitors and, of those who initially respond, 50% or more cease to respond within a year. Moreover, their use can be associated with significant safety issues. Clearly, there is a need to target alternative pathways involved in the inflammatory process. IBD is driven by the trafficking of lymphocytes from the circulation into the gut tissue that is mediated by adhesive interactions between the lymphocytes and endothelial cells. The adhesion molecules involved represent attractive targets for the development of new therapeutics which should aid in the resolution of existing inflammation, prevent recurrence of inflammation, and may potentially lead to long-term control of disease. In this article we review current opportunities and challenges facing anti-adhesion therapy in IBD, and discusses recent clinical development efforts that have focused on having an impact on two particular adhesive interactions: α(4)-integrin/MAdCAM-1 and β(2)-integrin/ICAM-1. Of particular interest is natalizumab, a humanized monoclonal antibody against human α(4) integrin that is approved for the treatment of patients with moderately-to-severely active CD and evidence of active inflammation. This agent represents an efficacious therapeutic option for patients who do not respond to, or have failed, a TNF-α inhibitor.

Down-regulation of adhesion molecules and matrix metalloproteinases by ZK 156979 in inflammatory bowel diseases

Intracellular adhesion molecules and matrix metalloproteinases (MMPs) are up-regulated in intestinal mucosa of patients with inflammatory bowel diseases (IBD), i.e. ulcerative colitis (UC) or Crohn's disease (CD). Our aim was to verify whether the vitamin D analogue ZK 156979 (ZK) down-regulates adhesion molecules, and decreases MMPs production by PBMC of IBD patients. ICAM-1 and LFA-1 levels increase, when PBMC were incubated with PHA or LPS or TNF-alpha, and decrease when these substances were used in combination with ZK. MMPs activity increases incubating the cells with PHA or LPS or TNF-alpha. MMP-9 decreases when ZK was used in association, while MMP-2 decreases only when ZK was used in combination with anti-TNF-alpha. Our results suggest that the down-regulation of ICAM-1 and LFA-1 on PBMC and the inhibition of MMP-9 activity by ZK could provide a potential role of this low calcemic vitamin D derivative in future strategies in IBD therapy.

T-cell-directed therapies in inflammatory bowel diseases

Gut inflammation occurring in patients with IBDs (inflammatory bowel diseases) is associated with exaggerated and poorly controlled T-cell-mediated immune responses, which are directed against normal components of the gut flora. T-cells accumulate in the inflamed gut of IBD patients as a result of multiple mechanisms, including enhanced recruitment of cells from the bloodstream, sustained cell cycling and diminished susceptibility of cells to undergo apoptosis. Activated T-cells produce huge amounts of cytokines, which contribute to amplify and sustain the ongoing mucosal inflammation. Strategies aimed at interfering with T-cell accumulation and/or function in the gut have been employed with clinical success in patients with IBDs. In the present article, we review the available results showing that T-cell-directed therapies are useful to dampen the tissue-damaging immune response in IBDs.

A systematic review and meta-analysis of anti-adhesion molecule therapy in patients with active Crohn's disease

OBJECTIVE

Due to the crucial role played by adhesion molecules in the pathogenesis of Crohn's disease (CD), targeting of these molecules has recently been proposed as a new direction for the development of anti-inflammatory strategies for CD. The aim of this study was to provide up-to-date evidence on the effectiveness and safety of anti-adhesion molecule therapy in treating active CD.

MATERIAL AND METHODS

We studied articles retrieved by PubMed, EMBASE, the Cochrane Library and the Science Citation Index for randomized controlled trials (RCTs) relevant to CD and anti-adhesion molecule therapy.

RESULTS

Seven RCTs comparing anti-adhesion molecule therapy with placebo were included in a meta-analysis to evaluate the efficacy and safety of anti-adhesion molecule strategies in active CD. On the basis of pooled results of the seven RCTs (n = 2228), we found a significant difference in clinical remission rates between groups [relative risk (RR) 1.31, 95% confidence interval (CI) 1.12-1.52, fixed-effect model]. Five RCTs (n = 2178) compared the response rates of anti-adhesion molecule therapy and placebo; in overall analysis, anti-adhesion molecule therapy was effective for active CD (RR 1.28, 95% CI 1.16-1.42, random-effect model). In five studies enrolling 1867 individuals, anti-adhesion molecule therapy did not increase adverse events (RR 1.03, 95% CI 0.98-1.08, fixed-effect model).

CONCLUSIONS

Anti-adhesion molecule therapy, which could prevent leukocyte recruitment, was effective and safe for treating active CD. Because of the small number of studies included in this meta-analysis, the results should be interpreted with caution.

alpha-Tocopheryl succinate as a scaffold to develop potent inhibitors of breast cancer cell adhesion

This study is aimed at the pharmacological exploitation of alpha-tocopheryl succinate (1) to develop potent antiadhesion agents. Considering the structural cooperativity between the phytyl chain and the carboxylic terminus in determining the antiadhesion activity, our structural optimization led to compound 5 ([2-(4,8-dimethyl-non-1-enyl)-2,5,7,8-tetramethyl-chroman-6-yloxy]-acetic acid), which exhibited an-order-of-magnitude higher potency than 1 in blocking the adhesion of 4T1 metastatic breast cancer cells to extracellular matrix proteins (IC(50), 0.6 microM versus 10 microM). Evidence indicates that the ability of compound 5 to block cell adhesion and migration was attributable to its effect on disrupting focal adhesion and actin cytoskeletal integrity by facilitating the degradation of focal adhesion kinase. Interactions between tumor cells and the ECM in the tumor microenvironment have been increasingly recognized as critical modulators of the metastatic potential of tumor cells. Consequently, the ability of compound 5 to block such interactions provides a unique pharmacological tool to shed light onto mechanisms that govern cell adhesion and tumor metastasis.

Role of sulfated O-glycans expressed by high endothelial venule-like vessels in pathogenesis of chronic inflammatory gastrointestinal diseases

Lymphocyte homing is mediated by a cascade of adhesive interactions between circulating lymphocytes and specialized endothelial cells comprising high endothelial venules (HEVs). Sulfated O-glycans expressed on HEVs, collectively called peripheral lymph node addressin (PNAd), interact with L-selectin expressed on lymphocytes, contributing to the initial step of the lymphocyte homing. In chronic inflammatory states, PNAd is induced on HEV-like vessels but absent in non-lymphoid tissues under normal conditions. Such HEV-like vessels have been observed in various chronic inflammatory diseases including rheumatoid arthritis, lymphocytic thyroiditis, Helicobacter pylori-associated chronic gastritis, and inflammatory bowel disease (IBD), and implicated in lymphocyte recruitment in those diseases. In H. pylori-associated chronic gastritis, PNAd-expressing HEV-like vessels are induced, and the progression of chronic inflammation is highly correlated with appearance of these vessels. Furthermore, eradication of H. pylori by antibiotics resulted in disappearance of PNAd. These results indicate that inhibition of PNAd formation could have therapeutic effect by attenuating lymphocyte recruitment. In ulcerative colitis (UC), PNAd-expressing HEV-like vessels are induced, preferentially in the active phase, and T cells, particularly CD4(+) T cells, are closely associated with these vessels, suggesting that T cell recruitment via PNAd-expressing HEV-like vessels plays at least a partial role in UC pathogenesis. Additionally, N-acetylglucosamine-6-O-sulfotransferase 1 (GlcNAc6ST-1) is suggested to be a candidate to regulate PNAd induction on HEV-like vessels in UC. These results provide a potential therapeutic strategy to treat UC by blocking T cell adhesion to PNAd-expressing HEV-like vessels. Inhibition or down-regulation of GlcNAc6ST-1 may be an alternative.

l-Tryptophan exhibits therapeutic function in a porcine model of dextran sodium sulfate (DSS)-induced colitis

Conventional therapies for the treatment of inflammatory bowel disease (IBD) have demonstrated limited efficacy and potential toxicity; therefore, there is a need for novel therapies that can safely and effectively treat IBD. Recent evidence has indicated that amino acids may play a role in maintaining gut health. L-tryptophan has been shown to reduce oxidative stress and improve neurological states. The objective of this study was to assess the therapeutic effects of L-tryptophan in a porcine model of dextran sodium sulfate (DSS)-induced colitis. DSS was administered to piglets via intragastric catheter for 5 days followed by tryptophan administration at 80% of the daily recommended intake. The severity of colitis was assessed macroscopically and histopathologically, and intestinal permeability was monitored in vivo by D-mannitol analysis. The effect of tryptophan on the local expression of key mediators of inflammation and IBD pathogenesis was examined at the protein and gene expression levels. Supplementation with tryptophan ameliorated clinical symptoms and improved weight gain to feed intake conversion ratios. Histological scores and measurements were also improved, and gut permeability was notably reduced in tryptophan-supplemented animals. Moreover, tryptophan reduced the expression of the pro-inflammatory cytokines tumor necrosis factor-alpha, interleukin (IL)-6, interferon (IFN)-gamma, IL-12p40, IL-1beta and IL-17, as well as IL-8 and intracellular adhesion molecule-1, and resulted in increased expression of apoptosis initiators caspase-8 and Bax. These results demonstrate that L-tryptophan supplementation can reduce inflammation and enhance the rate of recovery in DSS-induced colitis and may be an effective immunomodulating agent for the treatment of IBD.

Effect of Qingchang Supporsitory on expression of MAdCAM-1 in the colonic mucosa of rats with TNBS-induced colitis

AIM: To investigate the role of mucosal addressin cell adhesion molecule-1 (MAdCAM-1) in the pathogenesis of trinitrobenzene sulfonic acid (TNBS) induced rat colitis and to investigate the mechanisms underlying the anti-inflammatory action of Qingchang Supporistory (QCS).

METHODS: The TNBS induced rat colitis model was established. Rats were randomly divided into QCS high-dose group, QCS low-dose group, salicylazosulfapyridine (SASP) group, model Ⅰgroup, model Ⅱ group and normal group. Rats in model Ⅰ group were killed at day 3 while other rats were killed after 7 days' treatment. Histopathological assessment of the colonic mucosa was performed. LTB₄ and TNF-α in the colonic mucosa were determined using sandwich enzyme-linked immunosorbent assay (ELISA). Expression of MAdCAM-1 was determined using immunohistochemistry staining and Western blot.

RESULTS: Three days after TNBS administration, colonic mucosal injury occurred in model Ⅰ group while colonic mucosal injury was attenuated in QCS group after 7 days' treatment of QCS. Compared with normal group, the levels of LTB4 and TNF-α in colonic mucosal were raised in the model group (436.38 ± 66.56, 396.81 ± 69.43 vs 203.76 ± 42.84; 394.78 ± 61.53, 413.43 ± 47.39 vs 233.84 ± 55.24, P < 0.01). Compared with model II group, the colonic mucosa levels of LTB4 and TNF-α of all treatment groups were markedly decreased, especially in QCS high-dose group (275.74 ± 36.35, 282.72 ± 47.94, both P < 0.01). MAdCAM-1 was constitutively expressed on the lamina propria of normal colonic mucosa and the amount of positive staining cells dramatically were enhanced in model Ⅰ group. Compared with model Ⅱ group, the expression of MAdCAM-1 was significantly down-regulated in QCS high-dose group, QCS low-dose group and SASP group.

CONCLUSION: QCS performs significant anti-inflammatory action likely through inhibiting colonic mucosal LTB₄ and TNF-α production as well as down-regulating MAdCAM-1 expression.

Effect of Conventional and More Aggressive Rosuvastatin Treatment on Markers of Endothelial Activation

Treatment of hypercholesterolemia with HMG-CoA reductase inhibitors results in an earlier reduction of morbidity and mortality than expected from trials using conventional cholesterol-lowering therapies. Possible explanations for this effect include improvement of endothelial function, plaque stabilization, and inhibition of the inflammatory response associated with atherosclerosis. In this study we assessed the effects of low and moderate dose rosuvastatin treatment, on circulating markers of endothelial activation in patients admitted for acute coronary syndromes without ST segment elevation. Thirty patients with unstable angina and non ST segment elevation myocardial infarction were rando - mized into two groups, and received rosuvastatin 10 mg/day (n =16) or rosuvastatin 20 mg/day (n =14) for 12 weeks. Circulating levels of soluble vascular cell adhesion molecule (sVCAM-1) and intercellular adhesion molecule-1 (sICAM-1) were measured at admission, and at the end of the study. Lipid values were significantly reduced in both treatment groups, but with significantly greater reduction in the aggressively treated group. Serum levels of sICAM-1 and sVCAM-1 were significantly decreased in both rosuvastatin-treated groups during 12 weeks of follow-up with a more pronounced decrease in the more aggressively treated group. Therefore, rosuvastatin modulates endothelial activation in patients after acute coronary syndromes.

N-acetyl-L-cysteine combined with mesalamine in the treatment of ulcerative colitis: Randomized, placebo-controlled pilot study

AIM: To evaluate the effectiveness and safety of oral N-acetyl-L-cysteine (NAC) co-administration with mesalamine in ulcerative colitis (UC) patients.

METHODS: Thirty seven patients with mild to moderate UC were randomized to receive a four-wk course of oral mesalamine (2.4 g/d) plus N-acetyl-L-cysteine (0.8 g/d) (group A) or mesalamine plus placebo (group B). Patients were monitored using the Modified Truelove-Witts Severity Index (MTWSI). The primary endpoint was clinical remission (MTWSI ≤ 2) at 4 wk. Secondary endpoints were clinical response (defined as a reduction from baseline in the MTWSI of ≥ 2 points) and drug safety. The serum TNF-α, interleukin-6, interleukin-8 and MCP-1 were evaluated at baseline and at 4 wk of treatment.

RESULTS: Analysis per-protocol criteria showed clinical remission rates of 63% and 50% after 4 wk treatment with mesalamine plus N-acetyl-L-cysteine (group A) and mesalamine plus placebo (group B) respectively (OR = 1.71; 95% CI: 0.46 to 6.36; P = 0.19; NNT = 7.7). Analysis of variance (ANOVA) of data indicated a significant reduction of MTWSI in group A (P = 0.046) with respect to basal condition without significant changes in the group B (P = 0.735) during treatment. Clinical responses were 66% (group A) vs 44% (group B) after 4 wk of treatment (OR = 2.5; 95% CI: 0.64 to 9.65; P = 0.11; NNT = 4.5). Clinical improvement in group A correlated with a decrease of IL-8 and MCP-1. Rates of adverse events did not differ significantly between both groups.

CONCLUSION: In group A (oral NAC combined with mesalamine) contrarily to group B (mesalamine alone), the clinical improvement correlates with a decrease of chemokines such as MCP-1 and IL-8. NAC addition not produced any side effects.

Vitamin D derivatives induce apoptosis and downregulate ICAM-1 levels in peripheral blood mononuclear cells of inflammatory bowel disease patients

BACKGROUND

Lymphocytes are crucial in the pathogenesis of inflammatory bowel disease (IBD) and are an important target for drug development. Our aim was to verify whether 2 vitamin D derivatives, 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] and EB 1089, could induce cell apoptosis and affect cell-cell interaction by regulating adhesion molecule levels.

METHODS

Peripheral blood mononuclear cell (PBMC) proliferation was studied by [3H]thymidine incorporation and apoptosis was determined using an enzyme-linked immunosorbent assay (ELISA) kit. (Poly(ADP-ribose)polymerase (PARP) cleavage, caspase-3, and ICAM-1 protein levels were determined by Western blot analysis.

RESULTS

Our results indicate that 1,25(OH)2D3 or EB 1089 or anti-TNF-alpha (infliximab) induce apoptosis in PBMC obtained from healthy subjects. In IBD patients apoptosis is induced by vitamin D derivatives and by anti-TNF-alpha only in CD patients. Caspase-3 activation and PARP cleavage are registered when PBMC were treated with vitamin D derivatives. ICAM-1 levels remarkably increase when PBMC was incubated with lipopolysaccharide (LPS) or TNF-alpha. The treatment with the vitamin D derivatives, alone or in combination with LPS or TNF-alpha, significantly decreases ICAM-1 levels both in healthy subjects and IBD patients. In HUVEC cocultured with PBMC, previously incubated with LPS or TNF-alpha associated with 1,25(OH)2D3, ICAM-1 levels decrease both in healthy subjects and IBD patients.

CONCLUSIONS

1,25(OH)2D3 and EB 1089 inhibit PBMC proliferation, induce apoptosis in PBMC of healthy subjects and IBD patients, and affect ICAM-1 expression on PBMC and on HUVEC cocultured with PBMC, suggesting that the ICAM-1 downregulation could provide a new target for controlling the recruitment of leukocytes at the sites of inflammation in IBD.

Angiogenesis in inflammatory bowel disease

Both ulcerative colitis and Crohn's disease, the two major forms of inflammatory bowel diseases, are recognized, at the moment, as perplexing and challenging clinical entities, in which several molecules and cell types are implicated. Recent molecular evidence proposes the intestinal microvascular remodelling or angiogenesis, as a phenomenon implicated in the pathogenesis of these chronic inflammatory disorders, together with other proposed theories involved in the pathogenesis of inflammatory bowel diseases, such as genetic, microbacterial and immune factors. Intestinal damage is followed by a physiological angiogenesis, but the abnormal expression of pro- and anti-angiogenic molecules and the changes of vascular cell types could reflect a pathological vascular remodelling. Thus, the inflammation may be favoured and maintained by a pathological angiogenesis. A better understanding of the angiogenic process may facilitate the design of more effective therapies for chronic intestinal inflammation.

Natalizumab: pharmacology, clinical efficacy and safety in the treatment of patients with Crohn's disease

Natalizumab is a humanized monoclonal antibody against alpha4 integrin. In preclinical and clinical studies, natalizumab, which interferes with leukocyte trafficking in the intestinal tract, demonstrated effectiveness in inducing clinical response and maintaining remission in patients with moderate-to-severely active Crohn's disease. However, during clinical trials, three natalizumab-treated patients (one Crohn's disease patient and two multiple sclerosis patients) developed progressive multifocal leukoencephalopathy (PML). As a consequence of this unexpected serious adverse event, a retrospective safety evaluation was conducted; in that safety evaluation, no new cases of PML were identified. Natalizumab returned to the market in June 2006 for the treatment of relapsing multiple sclerosis. As of May 2007, an estimated 12,000 patients worldwide had received natalizumab, with no new confirmed cases of PML or opportunistic infections reported. Natalizumab is currently being investigated for use in treating patients with Crohn's disease. If it is approved for treatment of Crohn's patients, the clinical benefit of natalizumab should be weighed carefully against the potential risk of serious adverse events.

The correlation between proinflammatory cytokines, MAdCAM-1 and cellular infiltration in the inflamed colon from TNF-alpha gene knockout mice

Tumour necrosis factor (TNF) is important in the development of inflammatory bowel disease. TNF-alpha-deficient mice show more severe colonic inflammation than wild-type (Wt) mice, but the underlying mechanism remains unclear. Using immunohistochemistry, enzyme-linked-immunosorbent assay and histopathology, we found that there was a higher level of macrophage infiltration in TNF-alpha(-/-) compared to Wt mice. This is consistent with higher levels of monocyte chemotactic protein-1, interleukin (IL)-6 and granulocyte monocyte colony-stimulating factor (GM-CSF) in the inflamed colon from the TNF-alpha(-/-) mice, compared to the Wt mice, following dextran sulphate sodium (DSS) challenge. There was close correlation between clinical observations and histopathological findings in both Wt and TNF-alpha(-/-) mice. The expression of mucosal addressin cell adhesion molecule 1 (MAdCAM-1) was upregulated in the colon of Wt and TNF-alpha(-/-) mice following DSS challenge. Interestingly, the induction of MAdCAM-1 was relatively lower in the inflamed colon of TNF-alpha(-/-) mice, despite the higher inflammatory cell infiltrate, compared to their Wt counterparts. On the other hand, TNF-alpha(-/-) mice had significantly lower baseline levels of colonic IL-4, IL-6 and GM-CSF. Furthermore, there was a reduction of both immunoglobulin A (IgA) and IgG in the gut from TNF-alpha(-/-) mice following DSS challenge. These data indicate that TNF-alpha deficiency alters homoeostasis of the colonic chemokine/cytokine environment and humoral immune response, resulting in an exacerbation of acute DSS-induced colitis in TNF-alpha(-/-) mice. These findings support the idea that TNF-alpha plays a role in the acute stage of intestinal inflammation.

Preferential induction of peripheral lymph node addressin on high endothelial venule-like vessels in the active phase of ulcerative colitis

OBJECTIVES

In the colonic mucosa with ulcerative colitis (UC), it has been suggested that L-selectin-peripheral lymph node addressin (PNAd) interaction plays a role in lymphocyte recruitment, which requires PNAd induction on high endothelial venule (HEV)-like vessels. The present study was undertaken to elucidate how these HEV-like vessels participate in the pathogenesis of UC and also to determine whether the presence of such vessels is correlated with clinical outcomes.

METHODS

Biopsy specimens composed of active (N = 32) and remission (N = 12) phases of UC were subjected to immunohistochemistry for CD34, MECA-79, and HECA-452, and the immunostained sections were quantitatively analyzed. An in vitro binding assay with L-selectin*IgM chimeric protein was carried out to determine whether PNAd on HEV-like vessels formed in UC functions as an L-selectin ligand. RT-PCR was carried out to determine which enzyme is upregulated for PNAd biosynthesis on HEV-like vessels induced in the active phase of UC. Triple immunostaining for MECA-79 together with CD3 and CD20/CD79alpha, CD4 and CD8, or CXCR3 and ST2L was carried out to determine which lymphocyte population closely associates with these vessels.

RESULTS

PNAd-expressing HEV-like vessels were preferentially induced in the active phase of UC with increased transcription of the gene encoding N-acetylglucosamine-6-O-sulfotransferase (GlcNAc6ST)-1, which directs expression of the MECA-79 epitope. Moreover, T cells, particularly CD4(+) T cells, were more closely associated with these HEV-like vessels than B cells.

CONCLUSIONS

T-cell recruitment via PNAd-expressing HEV-like vessels induced by expression of GlcNAc6ST-1 may play a role in UC pathogenesis.

Adhesion molecules in chronic ulcerative colitis

BACKGROUND AND AIMS

The adhesion molecule expression in colonic mucosa is pivotal for transition from quiescent to active stage of ulcerative colitis (UC). The aim of the present study is to reveal the adhesion molecule profile of colonic mucosa in the active stage of UC and in remission.

MATERIALS AND METHODS

Biopsy specimens obtained from 14 patients with UC (seven with active disease and seven with UC in remission) and from seven controls were used. Immunohistochemistry was performed with antibodies against ICAM-1, VCAM-1, E-selectin, LFA-1, Mac-1, and VLA-4.

RESULTS

In controls, slight ICAM-1 positivity was observed on thety endothelium of blood vessels of the mucosal and submucosal layer and only single ICAM-1-, Mac-1-, and LFA-1-positive cells were found. In all patients with UC, the endothelium of venules in the edematous mucosal and submucosal layers was ICAM-1-, VCAM-1-, and E-selectin-positive. Numerous ICAM-1- and LFA-1-positive and less VCAM-1-, Mac-1-, and VLA-4-positive inflammatory cells were detected in mucous layers of acute UC. In specimens of UC in remission, the inflammatory cells positive for the studied adhesion molecules were significantly less in number in the mucosa and submucosa (p < 0.05).

CONCLUSIONS

Based on the increased expression of ICAM-1, VCAM-1, and their ligands LFA-1 and VLA-4 in patients with UC, we can conclude that these adhesion molecules play a key role in the adherence of lymphocytes and macrophages to endothelial cells maintaining the chronic inflammation. Presence of E-selectin on endothelial cells of venules could be a sign of relapse after remission in UC.

Relationship between mucosal addressin cell adhesion molecule-1 and ulcerative colitis

Mucosal addressin cell adhesion molecule-1 (MAdCAM-1) is an adhesion molecule that is preferentially expressed on the surface of vascular endothelial cells in intestinal tract and associated lymphoid tissues, and it is a major determinant of lymphocyte trafficking to the gut mucosa. The expression of MAdCAM-1 is dramatically increased in the inflammatory sites of ulcerative colitis (UC). This article reviews the molecular structure, distribution, biological function of MAdCAM-1 and its role in the pathogenesis of UC. It is also emphasized that MAdCAM-1 is a potential therapeutic target in UC.

Review article: biological activity markers in inflammatory bowel disease

BACKGROUND

Traditionally, inflammatory bowel disease activity is assessed by clinical activity indices that measure clinical symptoms and endoscopic indices that measure endoscopic inflammation. Biological markers are a non-invasive way of objectively measuring inflammation and can play an adjunctive or primary role in the assessment of disease activity.

AIM

To review the data on biological markers for assessment of disease activity and prediction of relapse in inflammatory bowel disease.

METHODS

To collect relevant articles, a PubMed search was performed from 1980 to 2006 using following search terms in combination: inflammatory bowel disease, biomarkers, inflammation, disease activity, relapse, acute phase reactants cytokines, interleukins, adhesion molecules, integrins, calprotectin and lactoferrin.

RESULTS

Biological activity markers can be classified into serological, faecal and miscellaneous categories. Acute phase reactants levels correlate with disease activity and some can be used to help predict relapse. Cytokines and adhesion molecules are elevated in active disease inconsistently. Faecal markers are useful in assessment of disease activity and relapse.

CONCLUSIONS

Acute phase reactants and faecal markers are useful to assess the disease activity in clinical practice. More data are required on cytokines and adhesion molecules. C-reactive protein, erythrocyte sedimentation rate, interleukins and faecal markers may be useful in predicting a relapse.

Substance P mediates antiapoptotic responses in human colonocytes by Akt activation

We examined the hypothesis that substance P (SP) and the neurokinin-1 receptor (NK-1R), both in vitro and in vivo, promote mucosal healing during recovery from colitis by stimulating antiapoptotic pathways in human colonic epithelial cells. For the in vitro experiments, human nontransformed NCM460 colonocytes stably transfected with NK-1R (NCM460-NK-1R cells) were exposed to SP, and cell viability assays, TUNEL assays, and Western blot analyses were used to detect apoptotic and antiapoptotic pathways. SP exposure of NCM460-NK-1R colonocytes stimulated phosphorylation of the antiapoptotic molecule Akt and inhibited tamoxifen-induced cell death and apoptosis evaluated by the cell viability assay and poly(ADP-ribose) polymerase cleavage, respectively. SP-induced phosphorylation of Akt and cleavage of poly(ADP-ribose) polymerase were inhibited by blockade of integrin alphaVbeta3, Jak2, and activation of phosphatidylinositol 3-kinase. For the in vivo experiments, C57BL/6 mice, administered 5% dextran sulfate (DSS) dissolved in tap water for 5 days followed by a 5-day recovery period, were treated with the NK-1R antagonist CJ-12,255 or vehicle. Vehicle-treated mice showed increased colonic Akt phosphorylation and apoptosis compared with mice that received no DSS. In contrast, daily i.p. administration of CJ-12,255 for 5 days post-DSS suppressed Akt activation, exacerbated colitis, and enhanced apoptosis, and pharmacologic inhibition of Akt, either alone or together with CJ-12,255, produced a similar effect. Thus, SP, through NK-1R, possesses antiapoptotic effects in the colonic mucosa by activating Akt, which prevents apoptosis and mediates tissue recovery during colitis.