Mechanisms of tissue damage in inflammatory bowel disease

Inflammatory Gene Panel Guiding the Study of Genetics in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a complex disease that develops through a sequence of molecular events that are still poorly defined. This process is driven by a multitude of context-dependent genes that play different roles based on their environment. The complexity and multi-faceted nature of these genes make it difficult to study the genetic basis of IBD. The goal of this article is to review the key genes in the pathophysiology of IBD and highlight new technology that can be used in further research. This paper examines Nanostring RNA probe technology, which uses tissue analyzed without the use of enzymes, transcription, or amplification. Nanostring offers several panels of genes to test, including an inflammation panel of 234 genes. This article analyzes this panel and reviews the literature for each gene's effect in IBD for use as a framework to review the pathophysiology of the disease. The panel was narrowed to 26 genes with significant evidence of mechanistic potential in IBD, which were then categorized into specific areas of pathogenesis. These include gut barrier breakdown, inappropriate recognition of commensal bacteria, immune cell activation, proinflammatory cytokine release, and subsequent impairment of the anti-inflammatory response. The eventual goal of this paper is the creation of a customized panel of IBD genes that can be used to better understand the genetic mechanism of IBD and aid in the development of future therapies in IBD.

Takayasu's arteritis associated with Crohn's disease treated with infliximab

A 23-year-old woman presented with fever, diarrhea, bloody stools, and arthralgia that did not improve despite previous treatments and was diagnosed with Crohn's disease. Remission was achieved after the introduction of infliximab, nutritional therapy, and 5-aminosalicylic acid treatment. However, the patient's blood sedimentation rate remained elevated without symptom recurrence, except for abdominal pain in the following year. Aortic wall thickening in the thoracic descending aorta was also observed on computed tomography. Accumulation in the thoracic descending aorta and abdominal aorta was confirmed using positron emission tomography-computed tomography. The patient was diagnosed with Takayasu's arteritis. The patient's abdominal symptoms resolved, and her blood sedimentation rate normalized after steroid administration.

Taraxacum coreanum Nakai extract attenuates lipopolysaccharide-induced inflammatory responses and intestinal barrier dysfunction in Caco-2 cells

ETHNOPHARMACOLOGICAL RELEVANCE

Taraxacum coreanum Nakai (TC) is a dandelion native to Korea that has long been used as a medicinal herb with antioxidant and anti-inflammatory properties. Intestinal inflammation is closely associated with intestinal epithelial barrier disruption, which leads to the progression of various intestinal diseases.

AIM OF THE STUDY

The aim of this study was to investigate the protective effects of TC extract on inflammatory responses and intestinal barrier dysfunction in lipopolysaccharide (LPS)-stimulated Caco-2 cells.

MATERIALS AND METHODS

The inhibitory effect of TC on nitric oxide (NO) and pro-inflammatory cytokines production were determined by Griess reagent and enzyme-linked immunosorbent assay, respectively. The epithelial permeability was evaluated by transepithelial electrical resistance (TEER) assay, and inflammation- and tight junction (TJ)-related protein expression were analyzed by Western blotting. In addition, the presence of ten active compounds was identified and quantified using UHPLC-ESI-MS and HPLC-DAD analyses.

RESULTS

Treatment with TC significantly reduced NO production and pro-inflammatory cytokines production [interleukin (IL)-6 and tumor necrosis factor (TNF)-α] compared to the group treated with LPS only, particularly at 100 μg/mL. TC significantly decreased monolayer permeability as detected by TEER. In addition, the transmission of fluorescein isothiocyanate-dextran 4 across the barrier was decreased after treatment with TC. Inflammation-related proteins (inducible NO synthase, cyclooxygenase-2, TNF-α, IL-6, and IL-1β) were down-regulated after treatment with TC. In contrast, TC significantly increased the protein levels of the TJ-related protein, claudin-5. Ten phytochemicals (protocatechuic acid, chlorogenic acid, caffeic acid, scopoletin, chicoric acid, hyperoside, nicotiflorin, luteoloside, sophoricoside, and luteolin) were identified by UHPLC-ESI-MS and HPLC-DAD analysis.

CONCLUSION

Our findings suggest that ethanolic extract of TC could attenuate the LPS-induced intestinal barrier dysfunction by increasing the TJ protein and suppressing inflammatory responses.

The Melanocortin System in Inflammatory Bowel Diseases: Insights into Its Mechanisms and Therapeutic Potentials

The melanocortin system is a complex set of molecular mediators and receptors involved in many physiological and homeostatic processes. These include the regulation of melanogenesis, steroidogenesis, neuromodulation and the modulation of inflammatory processes. In the latter context, the system has assumed importance in conditions of chronic digestive inflammation, such as inflammatory bowel diseases (IBD), in which numerous experiences have been accumulated in mouse models of colitis. Indeed, information on how such a system can counteract colitis inflammation and intervene in the complex cytokine imbalance in the intestinal microenvironment affected by chronic inflammatory damage has emerged. This review summarises the evidence acquired so far and highlights that molecules interfering with the melanocortin system could represent new drugs for treating IBD.

Smad7 as a positive regulator of intestinal inflammatory diseases

In physiological conditions, the human gut contains more immune cells than the rest of the body, but no overt tissue damage occurs, because several regulatory mechanisms control the activity of such cells thus preventing excessive and detrimental responses. One such mechanism relies on the action of transforming growth factor (TGF)-β1, a cytokine that targets both epithelial cells and many immune cell types. Loss of TGF-β1 function leads to intestinal pathology in both mice and humans. For instance, disruption of TGF-β1 signaling characterizes the destructive immune-inflammatory response in patients with Crohn's disease and patients with ulcerative colitis, the major human inflammatory bowel disease (IBD) entities. In these pathologies, the defective TGF-β1-mediated anti-inflammatory response is associated with elevated intestinal levels of Smad7, an antagonist of TGF-β1 signaling. Consistently, knockdown of Smad7 restores TGF-β1 function thereby attenuating intestinal inflammation in patients with IBD as well as in mice with IBD-like colitis. Up-regulation of Smad7 and reduced TGF-β1 signaling occurs also in necrotizing enterocolitis, environmental enteropathy, refractory celiac disease, and cytomegalovirus-induced colitis. In this article, we review the available data supporting the pathogenic role of Smad7 in the gastrointestinal tract and discuss whether and how targeting Smad7 can help attenuate detrimental immuno-inflammatory responses in the gut.

Low concentrations of Ambrosia maritima L. phenolic extract protect endothelial cells from oxidative cell death induced by H2O2 and sera from Crohn's disease patients

ETHNOPHARMACOLOGICAL RELEVANCE

A rising resort to herbal therapies in Crohn's disease (CD) alternative treatments has been recently observed due to their remarkable natural efficiency. In this context, the weed plant Ambrosia maritima L., traditionally known as Hachich el Aouinet in Algeria and as Damsissa in Egypt and Sudan, is widely used in North African folk medicine to treat infections, inflammatory diseases, gastrointestinal and urinary tract disturbances, rheumatic pain, respiratory problems, diabetes, hypertension and cancer.

AIM OF THE STUDY

To assess an Ambrosia maritima L. phenolic extract for its phenolic profile composition, its potential antioxidant activity in vitro, and its cytoprotective effect on cultured primary human endothelial cells (ECs) stressed with H₂O₂ and sera from CD patients.

MATERIALS AND METHODS

Phenolic compound extraction was performed with a low-temperature method. Extract chemical profile was attained by HPLC-DAD/ESI-MS. The extract in vitro antioxidant activity was assessed using several methods including cupric ion reducing power, DPPH radical scavenging assay, O-Phenanthroline free radical reducing activity, ABTS cation radical decolourisation assay, Galvinoxyl free radicals scavenging assay. Intracellular reactive oxygen species levels were evaluated in human endothelial cells by H₂DCFDA, while cell viability was assessed by MTT.

RESULTS

The phenolic compounds extraction showed a yield of 17.66% with three di-caffeoylquinic acid isomers detected for the first time in Ambrosia maritima L. Using different analytical methods, a significant in vitro antioxidant activity was reported for the Ambrosia maritima L. extract, with an IC₅₀ value of 14.33 ± 3.86 μg/mL for the Galvinoxyl antioxidant activity method. Challenged with ECs the Ambrosia maritima L. extract showed a biphasic dose-dependent effect on H₂O₂-treated cells, cytoprotective and antioxidant at low doses, and cytotoxic and prooxidant at high doses, respectively. Viability and ROS levels data also demonstrated a prooxidant and cytotoxic effect of CD sera on cultured ECs. Interestingly, 10 μg/mL of Ambrosia maritima L. extract was able to counteract both CD sera-induced oxidative stress and ECs death.

CONCLUSION

Our data indicated Ambrosia maritima L. as a source of bioactive phenolics potentially employable as a natural alternative for CD treatment.

Discovery of Novel Imidazo[4,5-c]quinoline Derivatives to Treat Inflammatory Bowel Disease (IBD) by Inhibiting Multiple Proinflammatory Signaling Pathways and Restoring Intestinal Homeostasis

As a complex pathogenesis driven by immune inflammatory factors and intestinal microbiota, the treatment of inflammatory bowel disease (IBD) may rely on the comprehensive regulation of these important pathogenic factors to reach a favorable therapeutic effect. In the current study, we discovered a series of imidazo[4,5-c]quinoline derivatives that potently and simultaneously inhibited two primary proinflammatory signaling pathways JAK/STAT and NF-κB. Especially, lead compound 8l showed potent inhibitory activities against interferon-stimulated genes (IC₅₀: 3.3 nM) and NF-κB pathways (IC₅₀: 150.7 nM) and decreased the release of various proinflammatory factors at the nanomolar level, including IL-6, IL-8, IL-1β, TNF-α, IL-12, and IFN-γ. In vivo, 8l produced a strong anti-inflammatory activity in both dextran sulfate sodium (DSS)- and 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced acute enteritis models and restored the structural composition of gut microbiota. Collectively, this study provided valuable lead compounds for the treatment of IBD and revealed the great anti-inflammatory potential of the simultaneous suppression of JAK/STAT and NF-κB signals.

PARK7/DJ-1 as a Therapeutic Target in Gut-Brain Axis Diseases

It is increasingly known that Parkinson's (PD) and Alzheimer's (AD) diseases occur more frequently in patients with inflammatory gastrointestinal diseases including inflammatory bowel (IBD) or celiac disease, indicating a pathological link between them. Although epidemiological observations suggest the existence of the gut-brain axis (GBA) involving systemic inflammatory and neural pathways, little is known about the exact molecular mechanisms. Parkinson's disease 7 (PARK7/DJ-1) is a multifunctional protein whose protective role has been widely demonstrated in neurodegenerative diseases, including PD, AD, or ischemic stroke. Recent studies also revealed the importance of PARK7/DJ-1 in the maintenance of the gut microbiome and also in the regulation of intestinal inflammation. All these findings suggest that PARK7/DJ-1 may be a link and also a potential therapeutic target in gut and brain diseases. In this review, therefore, we discuss our current knowledge about PARK7/DJ-1 in the context of GBA diseases.

In Vitro Protective Effects of a Standardized Extract From Cynara Cardunculus L. Leaves Against TNF-α-Induced Intestinal Inflammation

Inflammatory bowel disease (IBD) represents a group of progressive disorders characterized by recurrent chronic inflammation of the gut. New unconventional therapies based on plant derived compounds capable of preventing and/or reducing acute or chronic inflammation could represent a valid alternative for the treatment or prevention of IBDs. Cynara cardunculus L. leaves, considered a food-waste suitable as a rich source of bioactive polyphenols including luteolin and chlorogenic acid, has been reported for its positive effects in digestive tract. The aim of the present work was to evaluate the in vitro molecular mechanisms of beneficial effects of a standardized polyphenol-rich extract obtained from the leaves of Cynara cardunculus L (CCLE) against acute intestinal inflammation induced by TNF-α on intestinal epithelial Caco-2 cells. CCLE prevented TNF-α-induced NF-κB inflammatory pathway and the overexpression of IL-8 and COX-2. In addition, CCLE was able to improve basal intracellular antioxidant power in both TNF-α-unexposed or -exposed Caco-2 cells and this effect was associated to the activation of Nrf2 pathway, a master regulator of redox homeostasis affecting antioxidant and phase II detoxifying genes, stimulating an adaptive cellular response. In conclusion, our data clearly evidenced that, although considered a waste, Cynara cardunculus leaves may be used to obtain extracts rich in bioactive polyphenols potentially useful for prevention and treatment of inflammatory intestinal diseases.

Takayasu's Arteritis Diagnosed in an Adolescent Patient with Crohn's Disease: Management of Biologicals

We report a 14-year-old man with Crohn’s disease (CD) who developed right upper arm pain while being treated with the anti-tumor necrosis factor (TNF)-alpha monoclonal antibody, infliximab. There were no symptoms suggestive of active CD, but the inflammatory response was high, and a contrast-enhanced CT showed the occlusion of the right brachial artery. We diagnosed the patient as having Takayasu’s arteritis (TA) and started treatment with corticosteroids, then tapered off the steroids as the symptoms of TA resolved. Later, TA flared up, and his treatment was changed from infliximab to an anti-IL-6 receptor antibody, tocilizumab. The change to TCZ stabilized TA, but exacerbated CD. It is difficult to control both diseases at the same time, and the choice of biologics for treatment must be carefully considered.

Takayasu arteritis in an adolescent with Crohn's disease

Crohn’s disease (CD) and Takayasu arteritis (TA) are two distinct clinical entities. Τhe likelihood of both diseases coexisting is low, and although CD co-occurs with all types of vasculitis, TA is the most common subtype. Herein, the case of a 15-year-old female, diagnosed with TA following an initial diagnosis of CD, is reported. A review of the literature, including a systemic review of the case reports and case series of children and adolescents up to the age of 21, with both CD and TA, follows the case description. In total, 28 cases of TA and CD were retrieved. The median age of patients was 14.8 years, they were mostly females (72%) and the median time between the two diagnoses was 3.7 years. In the majority of cases, CD was diagnosed first and TA followed. Computed tomography angiography and magnetic resonance angiography were the preferred imaging modalities to assist diagnosis.

AphaMax®, an Aphanizomenon Flos-Aquae Aqueous Extract, Exerts Intestinal Protective Effects in Experimental Colitis in Rats

BACKGROUND

Aphanizomenon flos-aquae (AFA) is a unicellular cyanobacterium considered to be a "superfood" for its complete nutritional profile and beneficial properties. We investigated possible beneficial effects of an AFA extract, commercialized as AphaMax^®, containing concentrated amount of phycocyanins and phytochrome, in 2,4 dinitrobenzensulfonic acid(DNBS)-induced colitis in rats.

METHODS

Effects of preventive oral treatment of AphaMax^® (20, 50 or 100 mg/kg/day) in colitic rats were assessed and then macroscopic and microscopic analyses were performed to evaluate the inflammation degree. Myeloperoxidase (MPO) activity and NF-κB, pro-inflammatory citockines, cycloxygenase-2 (COX-2), and inducible NOS (iNOS) levels of expression were determined, as Reactive Oxygen Species (ROS) and nitrite levels.

RESULTS

AphaMax^® treatment attenuated the severity of colitis ameliorating clinical signs. AphaMax^® reduced the histological colonic damage and decreased MPO activity, NF-κB activation, as well as iNOS and COX-2 expression. AphaMax^® treatment improved the altered immune response associated with colonic inflammation reducing IL-1β, IL-6 expression. Lastly, AphaMax^® reduced oxidative stress, decreasing ROS and nitrite levels.

CONCLUSIONS

Preventive treatment with AphaMax^® attenuates the severity of the inflammation in DNBS colitis rats involving decrease of the NF-kB activation, reduction of iNOS and COX-2 expression, and inhibition of oxidative stress. Due its anti-inflammatory and antioxidant proprieties AphaMax^® could be a good candidate as a complementary drug in inflammatory bowel disease (IBD) treatment.

The pivotal relation between glucagon-like peptides, NFκB and inflammatory bowel disease

Glucagon-like peptides (GLPs), GLP-1 and GLP-2, are released from intestinal enteroendocrine cells (L cells) in response to ingested nutrients. GLP-1 plays a crucial role in lowering blood glucose and controlling body weight, through stimulating the islet ß cells of pancreas to secrete insulin, inhibiting gastric emptying, and reducing food ingestion. Therefore, GLP-1 receptor agonists are now used in the treatment of obese patients with type 2 diabetes mellitus (T2DM). GLP-2, on the other hand, is used as a novel therapy for short bowel syndrome (SBS) through its ability to restore intestinal homeostasis and induce epithelial proliferation. GLPs and the inhibitors of their degradation enzymes, dipeptidyl peptidase-IV (DPP-IV) inhibitors, have many anti-inflammatory actions. Many animal-based clinical trials have proved that GLP-based therapy has a pivotal role in the management of inflammatory bowel disease (IBD), possibly through regulating the transcription factor nuclear factor kappa-ligand B (NFκB). NFκB controls the production and secretion of many cytokines and chemokines encountered in the pathophysiology of IBD such as interleukin (IL-1β-IL-12, IL-13, IL-21, IL-22, IL-6) and tumour necrosis factor-alpha (TNF-α) and hence, may provide a promising therapeutic option.

lncRNA TUG1 regulates ulcerative colitis through miR-142-5p/SOCS1 axis

Ulcerative colitis (UC) is a long-lasting inflammation disease which finally results in ulcer of the colon and rectum. The long non-coding RNA (lncRNA) TUG1 has been described to target miR-142 and regulate its expression. In current study, we evaluated the effects of long non-coding RNA TUG1 on cell injury and inflammatory cytokine production using a TNFα-treated HT-29 cells model. We monitored the level of TUG1 in colonic mucosa tissue of UC patients and in TNF-α-treated HT-29 cells. We investigated the effects of TUG1 on miR-142-5p and SOCS1expression, cell viability, lactate dehydrogenase (LDH) release, production of nitrite and PGE2 after TNF-α treatment in HT-29 cells. We also investigated the effects of TUG1 on TNF-α-induced IL-6, IL-8 and IL-1β expression in HT-29 cells. We detected down-regulated TUG1 level in colonic mucosa tissue of UC patients and in TNF-α-treated HT-29 cells. Overexpression of TUG1 enhanced cell viability, decreased LDH release, decreased nitrite and PGE2 production after TNF-α treatment in HT-29 cells. TUG1 prevented IL-1β, IL-6 and IL-8 production in TNF-α-treated cells. TUG1 targeted miR-142-5p and inhibited its expression while enhanced SOCS1 expression. Overexpression of miR-142-5p abolished TUG1-mediated inhibition of TNF-induced inflammatory cytokines production. TUG1 negatively regulated inflammation in ulcerative colitis through miR-142-5p/SOCS1 axis.

Stevioside, a diterpenoid glycoside, shows anti-inflammatory property against Dextran Sulphate Sodium-induced ulcerative colitis in mice

Inflammatory bowel disease is an umbrella-term used to describe a set of chronic inflammatory conditions that affect the gastro-intestinal tract. Since most of the inflammatory medications in current use have several undesirable side-effects, stevioside, a naturally occurring, high-intensity sweetener was assessed in our study for its anti-inflammatory properties by in-vitro and in-vivo experiments. Stevioside was observed to significantly inhibit the levels of LPS induced elevation of cytokines, TNF-α (P < 0.05) and IL-6 (P < 0.001) as well as the production of reactive oxygen species (P < 0.01) and nitrites (P < 0.001) in RAW264.7 cells. Stevioside has also been evaluated for its anti-inflammatory effect by using dextran sulfate sodium (DSS)-induced ulcerative colitis model in mice. Stevioside significantly reduced the disease activity index (DAI) score, ameliorated the inflammatory symptoms induced by DSS in mice and exhibited intact colon histo-architecture. Stevioside treatment significantly inhibited the levels of pro-inflammatory cytokines, TNF-α and IL-6, and the protein expressions of pro-inflammatory mediators, COX-2 (P < 0.01) and iNOS (P < 0.01) and restored the levels of endogenous anti-oxidants such as superoxide dismutase (P < 0.01), catalase (P < 0.001), glutathione s-transferase (P < 0.001) and reduced glutathione (P < 0.001) level in colon tissues. It was also observed that stevioside significantly suppressed NF-κB (p65) activation by abrogating IκB phosphorylation and attenuated the phosphorylation of p38, ERK and JNK proteins in colon tissues. The findings of the present study suggest that stevioside exhibits anti-inflammatory property by inhibiting NF-κB (p65) and MAPK pathways and can be employed as an adjunct in nutraceuticals to treat IBD.

Curcumin and Intestinal Inflammatory Diseases: Molecular Mechanisms of Protection

Intestinal inflammatory diseases, such as Crohn’s disease, ulcerative colitis, and necrotizing enterocolitis, are becoming increasingly prevalent. While knowledge of the pathogenesis of these related diseases is currently incomplete, each of these conditions is thought to involve a dysfunctional, or overstated, host immunological response to both bacteria and dietary antigens, resulting in unchecked intestinal inflammation and, often, alterations in the intestinal microbiome. This inflammation can result in an impaired intestinal barrier allowing for bacterial translocation, potentially resulting in systemic inflammation and, in severe cases, sepsis. Chronic inflammation of this nature, in the case of inflammatory bowel disease, can even spur cancer growth in the longer-term. Recent research has indicated certain natural products with anti-inflammatory properties, such as curcumin, can help tame the inflammation involved in intestinal inflammatory diseases, thus improving intestinal barrier function, and potentially, clinical outcomes. In this review, we explore the potential therapeutic properties of curcumin on intestinal inflammatory diseases, including its antimicrobial and immunomodulatory properties, as well as its potential to alter the intestinal microbiome. Curcumin may play a significant role in intestinal inflammatory disease treatment in the future, particularly as an adjuvant therapy.

Regulation of Nuclear Factor Kappa-Light-Chain-Enhancer of Activated B Cells (NF-κβ) in Inflammatory Bowel Diseases

Inflammatory bowel diseases (IBD), encompassing both Crohn Disease (CD) and ulcerative colitis (UC) are globally prevalent diseases, impacting children of all ages. The hallmark of IBD is a perturbed immune system that leads to continuous inflammation in the gut and challenges optimal treatment. Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κβ), a nuclear transcription factor, plays a major role in gut homeostasis and contributes significantly toward a balanced, homeostatic immune system. Dysregulation in the NF-κβ pathway and factors that regulate it lead to a state of uncontrolled inflammation and altered immunity, as typically observed in IBD. Levels of proinflammatory cytokines that are regulated through NF-κβ are increased in both CD and UC. Genes known to activate NF-κβ, such as, Nucleotide-binding oligomerization domain-containing protein 2 (NOD2) and Interleukin 23 (IL-23), are associated with IBD. Factors involved in inhibition of NF-κβ, such as A20 and TOLLIP, are also affected in IBD, resulting in failed inflammation suppression/regulation. NOD-2 and A20 have specifically been found to be strongly associated with pediatric IBD. Gut commensals are known to exert anti-inflammatory activities toward NF-κβ and can have a potential role in attenuating inflammation that likely occurs due to microbial dysbiosis in IBD. Failure to terminate/downregulate NF-κβ signaling results in chronic inflammation in IBD. Well-regulated control of inflammation in children with IBD can help better control the disease and suppress immune responses. Better understanding of factors that control NF-κβ can potentially lead toward discovering targeted therapeutic interventions for IBD. Suppression of NF-κβ can be achieved through many modalities including anti-sense oligonucleotides (ASOs), siRNA (small interfering RNA), factors regulating NF-κβ, and microbes. This review focuses on the role of NF-κβ, especially in pediatric IBD, and potential therapeutic venues for attenuating NF-κβ-induced inflammation.

Anti-Inflammatory Properties of the Enaminone E121 in the Dextran Sulfate Sodium (DSS) Colitis Model

BACKGROUND

Enaminones are synthetic compounds with an established role in the prevention of various forms of seizures. Recent evidence suggests potent anti-tussive, bronchodilation and anti-inflammatory properties. Pre-treatment with particularly E121 compound resulted in a decrease in leukocyte recruitment in the ovalbumin induced-model of asthma, immune cell proliferation and cytokine release in vitro. We hypothesize that E121 might serve as a therapeutic potential in intestinal inflammation through modulating immune cell functions.

METHODS

Colitis was induced by daily dextran sulfate sodium (DSS) administration for 5 days, and its severity was determined by gross and histological assessments. The plasma level of various cytokines was measured using flow cytometry-based assay. The colonic expression/ phosphorylation level of various molecules was determined by immunofluorescence and western blotting. The effects of E121 treatment on in vitro neutrophil chemotaxis (under-agarose assay), superoxide release (luminol oxidation assay) and apoptosis (annexin V/7AAD) were also determined.

RESULTS

DSS-induced colitis in mice was significantly reduced by daily E121 treatment (30-100 mg/kg) at gross and histological levels. This effect was due to modulated plasma levels of interleukin (IL-2) and colonic expression levels of various signaling molecules and proteins involved in apoptosis. In vitro neutrophil survival, chemotaxis, and superoxide release were also reduced by E121 treatment.

CONCLUSION

Our results indicate important anti-inflammatory actions of E121 in the pathogenesis of IBD.

Application of Probiotics for the Production of Safe and High-quality Poultry Meat

Poultry industry has always been a dynamic and integral part of national economies in many countries. Economic losses incur especially in large-scale rearing facilities, often attributed to the deterioration of environmental conditions, poultry exposure to stressors and development of diseases. While antibiotics have been commonly used for prophylactic purposes and as growth stimulants, extensive documentation of antimicrobial resistance among pathogenic bacteria due to indiscriminate utilization of antibiotic in the industry has led to public and governmental outcries. Elimination of antibiotics from poultry production has thus encouraged intensive search for alternatives. In this review, we discuss the immense potential of probiotics to fill the gap as alternative growth promoters and evidences of beneficial effects of probiotic application in poultry production.

Inflammatory regulatory T cells in the microenvironments of ulcerative colitis and colon carcinoma

Foxp3(+)CD4(+) regulatory T (Treg) cells are thought to express negligible levels of effector cytokines, and inhibit immune responses and inflammation. Here, we have identified a population of IL-8(+)Foxp3(+)CD4(+) T cells in human peripheral blood, which is selectively increased in the microenvironments of ulcerative colitis and colon carcinoma. Phenotypically, this population is minimally overlapping with IL-17(+)Foxp3(+)CD4(+) T cells, and is different from IL-8(-)Foxp3(+)CD4(+) T cells in the same microenvironment. 40-60% of IL-8(+)Foxp3(+)CD4(+) T cells exhibit naive phenotype and express CD127, whereas IL-8(-)Foxp3(+)CD4(+) cells are basically memory T cells and express minimal CD127. The levels of CXCR5 expression are higher in IL-8(+)Foxp3(+) cells than in IL-8(-)Foxp3(+) cells. IL-2 and TGFβ induce IL-8(+)Foxp3(+) T cells. Exogenous Foxp3 expression promotes IL-8(+)Foxp3(+) T cells and inhibits effector cytokine IFNγ and IL-2 expression. Furthermore, Foxp3 binds to IL-8 proximal promoter and increases its activity. Functionally, IL-8(+)Foxp3(+) T cells inhibit T cell proliferation and effector cytokine production, but stimulate inflammatory cytokine production in the colon tissues, and promote neutrophil trafficking through IL-8. Thus, IL-8(+)Foxp3(+) cells may be an "inflammatory" Treg subset, and possess inflammatory and immunosuppressive dual biological activities. Given their dual roles and localization, these cells may be in a unique position to support tumor initiation and development in human chronic inflammatory environment.

Inflammatory bowel disease: mechanisms, redox considerations, and therapeutic targets

Oxidative stress is thought to play a key role in the development of intestinal damage in inflammatory bowel disease (IBD), because of its primary involvement in intestinal cells' aberrant immune and inflammatory responses to dietary antigens and to the commensal bacteria. During the active disease phase, activated leukocytes generate not only a wide spectrum of pro-inflammatory cytokines, but also excess oxidative reactions, which markedly alter the redox equilibrium within the gut mucosa, and maintain inflammation by inducing redox-sensitive signaling pathways and transcription factors. Moreover, several inflammatory molecules generate further oxidation products, leading to a self-sustaining and auto-amplifying vicious circle, which eventually impairs the gut barrier. The current treatment of IBD consists of long-term conventional anti-inflammatory therapy and often leads to drug refractoriness or intolerance, limiting patients' quality of life. Immune modulators or anti-tumor necrosis factor α antibodies have recently been used, but all carry the risk of significant side effects and a poor treatment response. Recent developments in molecular medicine point to the possibility of treating the oxidative stress associated with IBD, by designing a proper supplementation of specific lipids to induce local production of anti-inflammatory derivatives, as well as by developing biological therapies that target selective molecules (i.e., nuclear factor-κB, NADPH oxidase, prohibitins, or inflammasomes) involved in redox signaling. The clinical significance of oxidative stress in IBD is now becoming clear, and may soon lead to important new therapeutic options to lessen intestinal damage in this disease.

Integrating genetic and gene expression evidence into genome-wide association analysis of gene sets

Single variant or single gene analyses generally account for only a small proportion of the phenotypic variation in complex traits. Alternatively, gene set or pathway association analyses are playing an increasingly important role in uncovering genetic architectures of complex traits through the identification of systematic genetic interactions. Two dominant paradigms for gene set analyses are association analyses based on SNP genotypes and those based on gene expression profiles. However, gene-disease association can manifest in many ways, such as alterations of gene expression, genotype, and copy number; thus, an integrative approach combining multiple forms of evidence can more accurately and comprehensively capture pathway associations. We have developed a single statistical framework, Gene Set Association Analysis (GSAA), that simultaneously measures genome-wide patterns of genetic variation and gene expression variation to identify sets of genes enriched for differential expression and/or trait-associated genetic markers. Simulation studies illustrate that joint analyses of genomic data increase the power to detect real associations when compared with gene set methods that use only one genomic data type. The analysis of two human diseases, glioblastoma and Crohn's disease, detected abnormalities in previously identified disease-associated pathways, such as pathways related to PI3K signaling, DNA damage response, and the activation of NFKB. In addition, GSAA predicted novel pathway associations, for example, differential genetic and expression characteristics in genes from the ABC transporter family in glioblastoma and from the HLA system in Crohn's disease. These demonstrate that GSAA can help uncover biological pathways underlying human diseases and complex traits.

DNA promoter methylation status and protein expression of interleukin-8 in human colorectal adenocarcinomas

BACKGROUND

Interleukin-8 (IL-8) also referred to as CXCL8, a member of the CXC chemokine family that attracts neutrophils and other leukocytes, has been associated with cancer. Angiogenesis is a prime regulator of tumour expansion and data support that IL-8 is a potent angiogenic factor. Epigenomic instability has been postulated to play a role for the development of multiple neoplasias including colorectal cancer (CRC). DNA methylation of cytosine residues in CpG dinucleotides leads to transcriptional silencing of associated genes.

METHOD

In this study, we comparatively analysed the protein expression of IL-8 in plasma, tumour and paired normal tissue and methylation status of the IL-8 gene to evaluate its impact on CRC.

RESULTS

Collectively, by using Luminex technology, we noted a significantly higher IL-8 level in cancer tissue compared to paired normal tissue and that CRC patients exhibit significantly higher plasma levels than healthy controls. Analysed by methylation-specific polymerase chain reaction, we detected IL-8 hypomethylation in 64% of the cancerous tissue cases but no hypomethylation was found in paired normal tissue. We noted that the CRC patients with IL-8 hypomethylation revealed a significant higher level of IL-8 protein in cancerous tissue, which tended to be associated with distant metastasis. We also observed that patients with distant metastasis showed a significantly higher plasma level of IL-8 in relation to patients without distant metastasis.

CONCLUSION

Our results suggest that the predominance of high plasma levels of IL-8 in patients with distant metastasis in combination with the hypomethylation of the IL-8 promoter region might be a useful marker of the disease advancement.

Endogenous interleukin-10 constrains Th17 cells in patients with inflammatory bowel disease

Background

Th17 cells play a role in inflammation. Interleukin (IL)-10 is a potent anti-inflammatory cytokine. However, it is poorly understood whether and how endogenous IL-10 impacts the development of Th17 cells in human pathologies.

Materials and methods

We examined the relationship between IL-10 and Th17 cells in patients with Crohn's disease and in IL-10-deficient (IL-10^-/-) mice. Th17 cells and dendritic cells (DCs) were defined by flow cytometry and evaluated by functional studies.

Results

We detected elevated levels of IL-17 and Th17 cells in the intestinal mucosa of patients with Crohn's disease. Intestinal DCs from Crohn's patients produced more IL-1β than controls and were superior to blood DCs in Th17 induction through an IL-1-dependent mechanism. Furthermore, IL-17 levels were negatively associated with those of IL-10 and were positively associated those of IL-1β in intestinal mucosa. These data point toward an in vivo cellular and molecular link among endogenous IL-10, IL-1, and Th17 cells in patients with Crohn's disease. We further investigated this relationship in IL-10^-/- mice. We observed a systemic increase in Th17 cells in IL-10^-/- mice when compared to wild-type mice. Similar to the intestinal DCs in patients with Crohn's disease, murine IL-10^-/- DCs produced more IL-1β than their wild-type counterparts and promoted Th17 cell development in an IL-1-dependent manner. Finally, in vivo blockade of IL-1 receptor signaling reduced Th17 cell accumulation and inflammation in a mouse model of chemically-induced colitis.

Conclusions

Endogenous IL-10 constrains Th17 cell development through the control of IL-1 production by DCs, and reaffirms the crucial anti-inflammatory role of IL-10 in patients with chronic inflammation.

The association between inflammatory bowel disease and periodontitis among Jordanians: a case-control study

BACKGROUND AND OBJECTIVE

Inflammatory bowel disease (IBD) is hypothesized to involve immuno-inflammatory alterations, and the condition has been related to increased susceptibility to oral challenges. The objective of the study was to determine the association between the prevalence, severity and extent of periodontitis and both ulcerative colitis (UC) and Crohn's disease (CD).

MATERIAL AND METHODS

A case-control study was conducted among patients who attended outpatient clinics at King Hussein Medical City in Jordan during the study period. All participants completed the questionnaire and underwent thorough oral and periodontal examinations. Periodontitis was defined as presence of four or more teeth with one or more sites with probing pocket depth ≥ 4 mm and clinical attachment level ≥ 3 mm. The general linear model multivariate procedure and multivariate binary logistic regression were used to analyse the data.

RESULTS

This case-control study included 260 Jordanian adults (101 with UC, 59 with CD and 100 with no IBD) with a mean (SD) age of 39.4 (0.7) years. The prevalence of periodontitis was much higher among patients with CD and those with UC compared with subjects having no IBD in the age groups < 36 and 36-45 years old only. After adjusting for age and number of missing teeth, patients with CD (odds ratio 4.9, 95% confidence interval 1.8-13.2) and patients with UC (odds ratio 7.00, 95% confidence interval 2.8-17.5) had significantly higher odds of periodontitis than subjects with no IBD. In multivariate analysis, the severity of periodontitis was significantly higher among patients with CD and patients with UC when compared with subjects having no IBD. Ulcerative colitis patients but not CD patients had significantly higher prevalence of deep ulcers in oral soft tissues than the non-IBD group (p = 0.004).

CONCLUSION

Patients with IBD have higher prevalence, severity and extent of periodontitis compared with those having no IBD.

IL-17+ regulatory T cells in the microenvironments of chronic inflammation and cancer

Foxp3(+)CD4(+) regulatory T (Treg) cells inhibit immune responses and temper inflammation. IL-17(+)CD4(+) T (Th17) cells mediate inflammation of autoimmune diseases. A small population of IL-17(+)Foxp3(+)CD4(+) T cells has been observed in peripheral blood in healthy human beings. However, the biology of IL-17(+)Foxp3(+)CD4(+) T cells remains poorly understood in humans. We investigated their phenotype, cytokine profile, generation, and pathological relevance in patients with ulcerative colitis. We observed that high levels of IL-17(+)Foxp3(+)CD4(+) T cells were selectively accumulated in the colitic microenvironment and associated colon carcinoma. The phenotype and cytokine profile of IL-17(+)Foxp3(+)CD4(+) T cells was overlapping with Th17 and Treg cells. Myeloid APCs, IL-2, and TGF-β are essential for their induction from memory CCR6(+) T cells or Treg cells. IL-17(+)Foxp3(+)CD4(+) T cells functionally suppressed T cell activation and stimulated inflammatory cytokine production in the colitic tissues. Our data indicate that IL-17(+)Foxp3(+) cells may be "inflammatory" Treg cells in the pathological microenvironments. These cells may contribute to the pathogenesis of ulcerative colitis through inducing inflammatory cytokines and inhibiting local T cell immunity, and in turn may mechanistically link human chronic inflammation to tumor development. Our data therefore challenge commonly held beliefs of the anti-inflammatory role of Treg cells and suggest a more complex Treg cell biology, at least in the context of human chronic inflammation and associated carcinoma.

Inflammatory bowel disease

Inflammatory bowel diseases (IBDs) encompass ulcerative colitis, Crohn's disease, and indeterminate colitis, all of which are characterized by remission and exacerbation of gastrointestinal symptoms, and a variety of extraintestinal manifestations including those affecting the oral cavity. Although not particularly a cause for mortality, inflammatory bowel diseases are associated with significant morbidity and impact on the quality of life. This article reviews clinical presentation, diagnostic criteria, and therapeutic modalities for the 2 main types of inflammatory bowel disease and discusses manifestations of these conditions in the oral cavity. The role of the oral health care provider in timely recognition and referral for medical work-up as well as management of oral complaints is also emphasized.

Takayasu's arteritis in a patient with Crohn's disease: an unexpected association during infliximab therapy

We report a 20-year-old woman with Crohn's disease (CD) who developed anterior neck pain while being treated with the anti-tumor necrosis factor (TNF)-alpha monoclonal antibody, infliximab. She showed no symptoms suggestive of active CD except for tenderness along the left common carotid artery with marked increases in serum TNF-alpha and inflammatory reactions. Based on thickened walls of large vessels with enhancement effects on computed tomography, she was diagnosed as having associated Takayasu's arteritis (TA), which was successfully treated with corticosteroid. Even if CD is controlled by infliximab, other autoimmune disorders, such as TA, may develop as a complication.

Review article: anti-inflammatory mechanisms of action of Saccharomyces boulardii

BACKGROUND

Saccharomyces boulardii, a well-studied probiotic, can be effective in inflammatory gastrointestinal diseases with diverse pathophysiology, such as inflammatory bowel disease (IBD), and bacterially mediated or enterotoxin-mediated diarrhoea and inflammation.

AIM

To discuss the mechanisms of action involved in the intestinal anti-inflammatory action of S. boulardii.

METHODS

Review of the literature related to the anti-inflammatory effects of this probiotic.

RESULTS

Several mechanisms of action have been identified directed against the host and pathogenic microorganisms. S. boulardii and S. boulardii secreted-protein(s) inhibit production of proinflammatory cytokines by interfering with the global mediator of inflammation nuclear factor kappaB, and modulating the activity of the mitogen-activated protein kinases ERK1/2 and p38. S. boulardii activates expression of peroxisome proliferator-activated receptor-gamma (PPAR-gamma) that protects from gut inflammation and IBD. S. boulardii also suppresses 'bacteria overgrowth' and host cell adherence, releases a protease that cleaves C. difficile toxin A and its intestinal receptor and stimulates antibody production against toxin A. Recent results indicate that S. boulardii may interfere with IBD pathogenesis by trapping T cells in mesenteric lymph nodes.

CONCLUSIONS

The multiple anti-inflammatory mechanisms exerted by S. boulardii provide molecular explanations supporting its effectiveness in intestinal inflammatory states.

Genetic polymorphisms of interleukin 8 and risk of ulcerative colitis in the Chinese population

BACKGROUND

Interleukin-8 (IL-8), a CXC chemokine that recruits and activates inflammatory cells, plays a critical role in the pathogenesis of ulcerative colitis (UC). There are no studies on the association of single nucleotide polymorphisms (SNPs) of the IL-8 gene with the risk of UC.

METHODS

All 162 unrelated UC patients and 203 control subjects were analyzed for 5 IL-8 SNPs ((-845 (T/C), -738 (T/A), -353 (A/T), -251 (T/A) and +678 (T/C)) using polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) assay and PCR-sequence-specific primers (SSP) method. Serum IL-8 concentrations were measured in all subjects.

RESULTS

Individual SNPs were not associated with risk for UC. However, the frequency of -353A/-251A/+678T haplotype was significantly higher in UC patients than in healthy controls (OR=1.454, p=0.036). By subgroup analyses, this haplotype tended to be more common in severe UC patients than in those with mild-to-moderate disease (OR=2.281, p=0.027). Furthermore, patients with AAT diplotype showed significantly increased serum IL-8 concentrations than those with other diplotypes (p<0.001).

CONCLUSION

These results suggest that IL-8 is a novel susceptibility gene to UC in Chinese UC patients, and furthermore, that IL-8 polymorphisms may be related to severe clinical subtype of UC.

Chemotherapeutic Properties of n-3 Polyunsaturated Fatty Acids - Old Concepts and New Insights

Over the past several decades, data from both experimental animal studies and human clinical trials have shown that dietary n-3 polyunsaturated fatty acids (PUFA) exhibit anti-inflammatory bioactive properties, compared to n-6 PUFA. Collectively, these studies have identified multiple mechanisms by which n-3 PUFA affect immune cell responses. In this review, we discuss the putative targets of anti-inflammatory n-3 PUFA, specifically, cytokine production, antagonism of n-6 PUFA metabolism, binding to nuclear receptors as ligands, and the alteration of signaling protein acylation. In addition, we investigate the effect of n-3 PUFA on the coalescence of lipid rafts, specialized signaling platforms in the plasma membrane.

Inhibition of inflammation-induced alterations in rat small intestine by the herbal preparations STW 5 and STW 6

Inflammation is a common mechanism of many gastrointestinal diseases. Therefore, it is interesting to know, whether complex phytopharmaceuticals known to modulate gastrointestinal motor function reveal also anti-inflammatory properties. We tested the fixed herbal combination product STW 5 (Iberogast((R))) and its main component Iberis amara fresh plant extract (STW 6) to characterize their protective potential in an experimental inflammation model in vitro. The test system consisted of ileum/jejunum segments from male Wistar rats. Inflammation was evoked by intraluminal instillation of 2,4,6-trinitrobenzenesulfonic acid (TNBS) for 30min. Preincubation of TNBS together with STW 5 and STW 6 prevented the TNBS-induced inhibition of ACh-induced contractions. No differences were found between water-dissolved and ethanol-dissolved extracts. STW 5 and STW 6 reduced morphological changes induced by TNBS in mucosal and muscle layers. The IL-10 mRNA measured by qRT-PCR was not influenced by TNBS but increased by STW 5 and STW 6. The TNBS-induced increase in the TNFalpha-mRNA expression was suppressed by STW 5 but not by STW 6. Additionally, STW 5 decreased TNFalpha release in LPS-stimulated human monocytes. STW 6 influenced neither the TNFalpha-mRNA nor the TNFalpha release. These findings demonstrate that STW 5 reduced inflammation-induced alterations in ileum/jejunum segments. The effects were associated with a restoration of the disturbed ACh-induced contraction, pathohistological protection and inhibition of TNFalpha. STW 6 may contribute to the protective effect of STW 5 mainly by increasing IL-10 pathway but not by influencing TNFalpha.

Hypoxia. Regulation of NFkappaB signalling during inflammation: the role of hydroxylases

NFκB is a master regulator of innate immunity and inflammatory signalling. Microenvironmental hypoxia has long been identified as being coincident with chronic inflammation. The contribution of microenvironmental hypoxia to NFκB-induced inflammation has more recently been appreciated. Identification of the co-regulation of NFκB and hypoxia inducible factor (HIF) pathways by 2-oxo-glutarate-dependent hydroxylase family members has highlighted an intimate relationship between NFκB inflammatory signalling and HIF-mediated hypoxic signalling pathways. Adding another layer of complexity to our understanding of the role of NFκB inflammatory signalling by hypoxia is the recent recognition of the contribution of basal NFκB activity to HIF-1α transcription. This observation implicates an important and previously unappreciated role for NFκB in inflammatory disease where HIF-1α is activated. The present review will discuss recent literature pertaining to the regulation of NFκB inflammatory signalling by hypoxia and some of the inflammatory diseases where this may play an important role. Furthermore, we will discuss the potential for prolylhydroxylase inhibitors in inflammatory disease.

Inhibitory effects of short-chain fatty acids on matrix metalloproteinase secretion from human colonic subepithelial myofibroblasts

BACKGROUND AND AIMS

Short-chain fatty acids (SCFAs), such as acetate, propionate and butyrate, are the major by-product of bacterial fermentation of dietary fiber in the colon. In this report, we investigated how SCFAs modulate matrix metalloproteinase (MMP) secretion from human colonic subepithelial myofibroblasts (SEMFs).

MATERIALS AND METHODS

SEMFs were identified by expression of alpha-smooth muscle actin and vimentin. Cytokine-induced MMP-1 and MMP-3 levels were determined by enzyme-linked immunosorbent assay. Cytokine-induced MMP mRNA expression was analyzed by RT-PCR and real-time PCR methods.

RESULTS

Acetate had no effect on MMP secretion. Propionate and butyrate significantly attenuated IL-1 beta- and TNF-alpha-induced MMP-1 and MMP-3 secretion. Similar responses were also observed at the mRNA levels. Propionate and butyrate did not modulate IL-1 beta- and TNF-alpha-induced activation of mitogen-activated protein kinases (MAPKs), which play a crucial role in MMP induction. Trichostatin A, a histone-deacetylase inhibitor, reduced IL-1 beta-induced MMP-1 and MMP-3 mRNA expression, and suppressed TNF-alpha-induced MMP-3 mRNA expression.

CONCLUSION

SCFAs play an anti-inflammatory role through suppression of MMP secretion in the colon. Inhibitory effects of SCFAs on MMP secretion might be associated with their action of histone hyperacetylation.

Signature biomarkers in Crohn's disease: toward a molecular classification

In an effort to develop a molecular classification scheme for Crohn's disease (CD), mucosal biopsies from 69 CD patients and 28 normal controls were analyzed for expression of the RelA subunit of nuclear factor (NF)-kappaB, A20 (a negative regulator of NF-kappaB), polymeric immunoglobulin receptor (pIgR), tumor necrosis factor (TNF), and interleukin (IL)-8. Principal component analysis was used to classify individuals into three subsets based on patterns of biomarker expression. Set 1 included normal subjects and CD patients with mild disease and good responses to therapy, thus defining "normal" biomarker expression. CD patients in set 2, characterized by low expression of all five biomarkers, had moderate to severe disease and poor responses to immunosuppressive and anti-TNF therapy. Patients in set 3, characterized by low expression of RelA, A20, and pIgR, normal TNF and elevated IL-8, had acute inflammation that responded well to therapy. Classification of CD patients by these biomarkers may predict disease behavior and responses to therapy.

Takayasu’s arteritis following Crohn’s disease in a young woman: Any evidence for a common pathogenesis?

Takayasu’s arteritis and Crohn’s disease are chronic inflammatory diseases of uncertain aetiology. They rarely occur together, with only twenty nine cases of co-existent Takayasu’s arteritis and Crohn’s disease reported in the literature. In 88% of these cases, Takayasu’s arteritis was diagnosed simultaneously or following a diagnosis of Crohn’s disease. We present a case of a young Caucasian medical student, incidentally found to have bilateral carotid bruits on auscultation by a colleague. Magnetic resonance angiography revealed stenoses of the common carotid arteries with established collaterals, and a diagnosis of Type 1 Takayasu’s arteritis was made. An 18^F-fluorodeoxyglucose positron emission tomography scan revealed no active disease. Nine months later, she presented with a short history of abdominal pain, vomiting and abdominal distension. Barium follow-through and computer tomography revealed a terminal ileal stricture and proximal small bowel dilation. An extended right hemicolectomy was performed and histopathology supported a diagnosis of Crohn’s disease. This case report is presented with a particular focus on the temporal relationship between these two disease processes and explores whether their concurrence is more than just co-incidence.

Non-invasive techniques for assessing postoperative recurrence in Crohn's disease

Postoperative recurrence after ileo-colonic resection is a feature of Crohn's Disease (CD), almost 73% of patients show endoscopic recurrence at 1 year and 90% at 3 years. After surgical resection for CD, symptoms may be related to the surgical resection itself. Moreover, the development of an early severe endoscopic recurrence within 1 year represents a risk factor for early clinical recurrence. On the basis of these observations, the early detection and assessment of asymptomatic endoscopic recurrence may allow a timely and appropriate treatment of CD patients after ileo-colonic resection. At this purpose, conventional colonoscopy with ileoscopy currently represents the gold standard for assessing CD recurrence, graded according to the Rutgeerts' score. Lesions compatible with CD recurrence can be also detected by conventional radiology, including small bowel follow through and enema, both associated with a high radiation exposure. Due to the ineluctable course of CD after resection, and to the need of a proper follow up for assessing CD recurrence, several alternative, non invasive techniques have been searched in order to assess the post-operative recurrence, including: faecal alpha 1-antitrypsin clearance, faecal calprotectin, 99Tc-HMPAO scintigraphy, virtual colonoscopy, ultrasonography and, more recently, wireless capsule endoscopy (WCE) and Small Intestine Contrast Ultrasonography (SICUS). Among these, current evidences suggest that in experienced hands, ultrasound examination by SICUS represents a non-invasive technique useful for assessing recurrence in CD patients under regular follow up after surgery. The same findings are suggested for WCE, although the impact risk related to the recurrence or to the surgical anastomosis itself limits the use of this non-invasive technique for assessing CD recurrence after surgery.

CD4-expressing cells are early mediators of the innate immune system during sepsis

It is well established that the immune response to sepsis is mediated by leukocytes associated with the innate immune system. However, there is an emerging view that T lymphocytes can also mediate this response. Here, we observed a significant depletion of both CD4 and CD8 T cells in human patients after blunt trauma. To determine what effect the loss of these cells may have during a subsequent infection, we obtained CD4- and CD8-deficient mice and subjected them to cecal ligation and puncture (CLP). We observed that CD4 knockout (KO) mice showed increased CLP-induced mortality compared with CD8-deficient and wild-type (WT) mice especially within the first 30 h of injury. CD4 KO mice also exhibited significantly increased IL-6 concentrations after the CLP. The CD4 KO mice had an increased concentration of bacteremia as compared with WT mice. Antibiotic treatment decreased mortality in the CD4 KO mice as compared with no changes in the wild mice after CLP. Neutrophils isolated from septic CD4 KO mice showed decreased spontaneous oxidative burst compared with neutrophils taken from septic controls. We examined the role of IFN-gamma by using mice deficient in this cytokine and found these mice to have significantly higher mortality as compared with WT mice. Finally, we detected a 2-fold increase in CD11b+ cells that exhibited intracellular IFN-gamma staining in the peritoneum of WT mice after CLP. The data suggest that CD4+ cells may facilitate the early clearance of bacteria by regulating neutrophils function possibly through an IFN-gamma-dependent mechanism.

NF-kappaB in inflammatory bowel disease

Apart from genetic and environmental factors, the mucosal immune system of the gut plays a central role in the pathogenesis of inflammatory bowel disease (IBD). In the healthy gut, the mucosal immune system ensures the balance between pro- and anti-inflammatory mediators and thereby allows an effective defence against luminal pathogens but at the same time prevents an overwhelming immune reaction directed against the huge amount of harmless luminal antigens (for example, components of food or nonpathological bacteria). In both entities of IBD (Crohn's disease and ulcerative colitis) this immunological balance is severely impaired and shifted towards the pro-inflammatory side. The chronic mucosal inflammation in IBD is caused by hyperactivation of effector immune cells, which produce high levels of pro-inflammatory cytokines like tumour necrosis factor-alpha, interleukin-6 and interferon-gamma, resulting in colonic tissue damage. The nuclear transcription factor kappaB (NF-kappaB) was identified as one of the key regulators in this immunological setting. Its activation is markedly induced in IBD patients and through its ability to promote the expression of various pro-inflammatory genes, NF-kappaB strongly influences the course of mucosal inflammation. Considering the different cell-type specific effects which are mediated by NF-kappaB, this review aims at describing the complex role of NF-kappaB in IBD and discusses existing pharmacological attempts to block the activation of NF-kappaB to develop new therapeutic strategies in IBD.

Prevalence of periodontitis and DMFT index in patients with Crohn's disease and ulcerative colitis

AIM

To compare the prevalence of periodontal disease and the decayed, missing and filled teeth (DMFT) index in patients with Crohn's disease (CD) and ulcerative colitis (UC) with those without these diseases.

MATERIAL AND METHODS

Ninety-nine CD (39.0 SD+/-12.9 years), 80 UC (43.3 SD+/-13.2) and 74 healthy controls (40.3 SD+/-12.9) were compared for DMFT index and presence of periodontitis. Probing pocket depth (PPD), clinical attachment loss (CAL), bleeding on probing (BOP), plaque and DMFT index were measured on all subjects. The presence of periodontitis was defined as having CAL > or =3 mm in at least four sites in different teeth.

RESULTS

Significantly more patients with UC (90.0%; p<0.001) and CD (81.8%; p=0.03) had periodontitis than controls (67.6%). Among smokers, UC patients had significantly more periodontitis. CD had a greater mean DMFT score (18.7 versus 13.9; p=0.031) compared with controls and UC had greater median PPD (2.2 versus 1.7 mm; p<0.0001) than controls. Among non-smokers, CD (2.4 mm; p<0.0001) and UC showed deeper pockets (2.3 mm; p<0.0001) compared with controls (1.5 mm). UC had a greater mean DMFT score (15.3 versus 12.1; p=0.037) compared with controls.

CONCLUSIONS

CD and UC patients had higher DMFT and prevalence of periodontitis than controls, but smoking was an effect modifier.

Angiogenesis and chronic inflammation: cause or consequence?

Evidence has been gathered regarding the association between angiogenesis and inflammation in pathological situations. These two phenomena have long been coupled together in many chronic inflammatory disorders with distinct etiopathogenic origin, including psoriasis, rheumatoid arthritis, Crohn's disease, diabetes, and cancer. Lately, this concept has further been substantiated by the finding that several previously established non-inflammatory disorders, such as osteoarthritis and obesity, display both inflammation and angiogenesis in an exacerbated manner. In addition, the interplay between inflammatory cells, endothelial cells and fibroblasts in chronic inflammation sites, together with the fact that inflammation and angiogenesis can actually be triggered by the same molecular events, further strengthen this association. Therefore, elucidating the underlying cellular and molecular mechanisms that gather together the two processes is mandatory in order to understand their synergistic effect, and to develop new therapeutic approaches for the management of these disorders that cause a great deal of discomfort, disability, and in some cases death.

Role of fibroblast growth factor-2 in the expression of matrix metalloproteinases and tissue inhibitors of metalloproteinases in human intestinal myofibroblasts

BACKGROUND AND AIMS

The coordinated expression of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) plays a crucial role in tissue remodeling. We investigated the effects of fibroblast growth factor (FGF)-2 on the secretion of MMPs and TIMPs in human intestinal subepithelial myofibroblasts (SEMFs).

METHODS

The secretion of MMP-s and TIMPs was determined by ELISA or Western blotting. The mRNA expression of MMPs and TIMPs was assessed by Northern blotting. The activating protein (AP)-1-DNA binding activity was evaluated by electrophoretic gel mobility shift assays (EMSA).

RESULTS

Unstimulated intestinal SEMFs constitutively secreted MMP-2 and TIMP-2. FGF-2 stimulated MMP-1, MMP-3 and TIMP-1 secretion, but did not affect MMP-2 or TIMP-2 secretion. FGF-2 induced AP-1-DNA binding activity, and the c-Jun/AP-1 inhibitor curcumin attenuated the FGF-2-induced MMP-1, -3 and TIMP-1 mRNA expression. Mitogen-activated protein (MAP) kinase inhibitors (U0126 and PD098059) also blocked the MMP-1, -3 and TIMP-1 secretion. Furthermore, FGF-2 dose-dependently induced FGF-2 mRNA expression in these cells.

CONCLUSIONS

FGF-2 may be one of important regulatory factors for extracellular matrix turnover via a modulation of MMP and TIMP secretion from SEMFs.