Cytokine messenger RNA profiles in inflammatory bowel disease mucosa detected by polymerase chain reaction amplification

Interleukin-1 receptor antagonist: a promising cytokine against human squamous cell carcinomas

Inflammation, especially chronic inflammation, is closely linked to tumor development. As essential chronic inflammatory cytokines, the interleukin family plays a key role in inflammatory infections and malignancies. The interleukin-1 (IL-1) receptor antagonist (IL1RA), as a naturally occurring receptor antagonist, is the first discovered and can compete with IL-1 in binding to the receptor. Recent studies have revealed the association of the polymorphisms in IL1RA with an increased risk of squamous cell carcinomas (SCCs), including squamous cell carcinoma of the head and neck (SCCHN), cervical squamous cell carcinoma, cutaneous squamous cell carcinoma (cSCC), esophageal squamous cell carcinoma (ESCC), and bronchus squamous cell carcinoma. Here, we reviewed the antitumor potential of IL1RA as an IL-1-targeted inhibitor.

Swimming exercise is a promising early intervention for autism-like behavior in Shank3 deletion rats

INTRODUCTION

SHANK3 is an important excitatory postsynaptic scaffold protein, and its mutations lead to genetic cause of neurodevelopmental diseases including autism spectrum disorders (ASD), Philan McDermid syndrome (PMS), and intellectual disability (ID). Early prevention and treatment are important for Shank3 gene mutation disease. Swimming has been proven to have a positive effect on neurodegenerative diseases.

METHODS

Shank3 gene exon 11-21 knockout rats were intervened by a 40 min/day, 5 day/week for 8-week protocol. After the intervention, the rats were tested to behavioral measures such as learning and memory, and the volume and H-spectrum of the brain were measured using MRI; hippocampal dendritic spines were measured using Golgi staining and laser confocal.

RESULTS

The results showed that Shank3-deficient rats had significant deficits in social memory, object recognition, and water maze learning decreased hippocampal volume and number of neurons, and lower levels of related scaffold proteins and receptor proteins were found in Shank3-deficient rats.

CONCLUSION

It is suggested that early swimming exercise has a positive effect on Shank3 gene-deficient rats, which provides a new therapeutic strategy for the prevention and recovery of neurodevelopmental disorders.

The Importance of CXCL1 in the Physiological State and in Noncancer Diseases of the Oral Cavity and Abdominal Organs

CXCL1 is a CXC chemokine, CXCR2 ligand and chemotactic factor for neutrophils. In this paper, we present a review of the role of the chemokine CXCL1 in physiology and in selected major non-cancer diseases of the oral cavity and abdominal organs (gingiva, salivary glands, stomach, liver, pancreas, intestines, and kidneys). We focus on the importance of CXCL1 on implantation and placentation as well as on human pluripotent stem cells. We also show the significance of CXCL1 in selected diseases of the abdominal organs, including the gastrointestinal tract and oral cavity (periodontal diseases, periodontitis, Sjögren syndrome, Helicobacter pylori infection, diabetes, liver cirrhosis, alcoholic liver disease (ALD), non-alcoholic fatty liver disease (NAFLD), HBV and HCV infection, liver ischemia and reperfusion injury, inflammatory bowel disease (Crohn’s disease and ulcerative colitis), obesity and overweight, kidney transplantation and ischemic-reperfusion injury, endometriosis and adenomyosis).

Could Mucosal TNF Transcript as a Biomarker Candidate Help Optimize Anti-TNF Biological Therapy in Patients With Ulcerative Colitis?

Anti-tumor necrosis factor (TNF) biological therapy has generally been accepted as a standard therapeutic option in inflammatory bowel disease (IBD) patient who are refractory to steroids or immunomodulators. However, the primary and secondary nonresponse rates to anti-TNF bioagents in patients with IBD are high. To improve the response rate, anti-TNF bioagents must be offered to the appropriate IBD patients, and the withdrawal of anti-TNF bioagents needs to be done at the right time. In this context, reliable and reproducible biomarkers can provide important supportive information for clinicians to make correct decisions based on the patient’s individual situation. In this review, we summarized the current understanding of using mucosal TNF transcript (TNF) to improve the precision of anti-TNF biological therapy strategies in patients with ulcerative colitis (UC). Analysis of published literature showed that mucosal TNF could affect the precision of the early identification of candidates who will benefit from anti-TNF therapy prior to treatment, the assessment of response and mucosal healing, and the prediction of discontinuation of anti-TNF biological therapy and relapse after drug withdrawal. Challenges and limitations of using mucosal TNF as a biomarker in applying individualized anti-TNF biological therapy in patients with UC still remain and need to be further investigated.

IL1B Increases Intestinal Tight Junction Permeability by Up-regulation of MIR200C-3p, Which Degrades Occludin mRNA

BACKGROUND & AIMS

Defects in the epithelial tight junction (TJ) barrier contribute to development of intestinal inflammation associated with diseases. Interleukin 1 beta (IL1B) increases intestinal permeability in mice. We investigated microRNAs that are regulated by IL1B and their effects on expression of TJ proteins and intestinal permeability.

METHODS

We used Targetscan to identify microRNAs that would bind the 3' untranslated region (3'UTR) of occludin mRNA; regions that interacted with microRNAs were predicted using the V-fold server and Assemble2, and 3-dimensional models were created using UCSF Chimera linked with Assemble2. Caco-2 cells were transfected with vectors that express microRNAs, analyzed by immunoblots and real-time polymerase chain reaction (PCR), and grown as monolayers; permeability in response to IL1B was assessed with the marker inulin. Male C57BL/6 mice were given intraperitoneal injections of IL1B and intestinal recycling perfusion was measured; some mice were given dextran sodium sulfate to induce colitis and/or gavage with an antagonist to MIR200C-3p (antagomiR-200C) or the nonspecific antagomiR (control). Intestinal tissues were collected from mice and analyzed by histology and real-time PCR; enterocytes were isolated by laser capture microdissection. We also analyzed colon tissues and organoids from patients with and without ulcerative colitis.

RESULTS

Incubation of Caco-2 monolayers with IL1B increased TJ permeability and reduced levels of occludin protein and mRNA without affecting the expression of other transmembrane TJ proteins. Targetscan identified MIR122, MIR200B-3p, and MIR200C-3p, as miRNAs that might bind to the occludin 3'UTR. MIR200C-3p was rapidly increased in Caco-2 cells incubated with IL1B; the antagomiR-200c prevented the IL1B-induced decrease in occludin mRNA and protein and reduced TJ permeability. Administration of IL1B to mice increased small intestinal TJ permeability, compared with mice given vehicle; enterocytes isolated from mice given IL1B had increased expression of MIR200C-3p and decreased levels of occludin messenger RNA (mRNA) and protein. Intestinal tissues from mice with colitis had increased levels of IL1B mRNA and MIR200C-3p and decreased levels of occludin mRNA; gavage of mice with antagomiR-200C reduced levels of MIR200C-3p and prevented the decrease in occludin mRNA and the increase in colonic permeability. Colon tissues and organoids from patients with ulcerative colitis had increased levels of IL1B mRNA and MIR200C-3p compared with healthy controls. Using 3-dimensional molecular modeling and mutational analyses, we identified the nucleotide bases in the occluding mRNA 3'UTR that interact with MIR200C-3p.

CONCLUSIONS

Intestine tissues from patients with ulcerative colitis and mice with colitis have increased levels of IL1B mRNA and MIR200C-3p, which reduces expression of occludin by enterocytes and thereby increases TJ permeability. Three-dimensional modeling of the interaction between MIR200C-3p and the occludin mRNA 3'UTR identified sites of interaction. The antagomiR-200C prevents the decrease in occludin in enterocytes and intestine tissues of mice with colitis, maintaining the TJ barrier.

Serratane triterpenoids isolated from Lycopodium clavatum by bioactivity-guided fractionation attenuate the production of inflammatory mediators

Lycopodium clavatum has been used in traditional medicine for the treatment of kidney disorders, rheumatic arthritis, cystitis, and gastritis. We isolated a new serratane triterpenoid (2), and five known triterpenoids (1, 3-6) from the ethyl acetate fraction of L. clavatum by bioactivity-guided fractionation based on their suppression of inflammatory cytokines. Two different cell lines, RAW 264.7 and HT-29 were used to determine the anti-inflammatory activity of the isolated compounds. Among them, compounds 1, 2, 4, and 5 significantly inhibited the production of lipopolysaccharide (LPS)-induced NO in macrophages. Compounds 1, 2, 4, and 5 reduced inducible nitric oxide (iNOS) expression in RAW 264.7 cells and compounds 1 and 6 downregulated COX-2, which correlated with the reduced expression of PGE2. Compounds 1, 2, 4, and 5 downregulated pro-inflammatory cytokines, such as interleukin-1β (IL-1β) in macrophages, and additionally suppressed the levels of IL-8 in HT-29 cells. To determine the signaling pathways involved in the suppression of NO production by these compounds, we investigated ERK1/2 and nuclear factor-kappa B (NF-κB) expression by western blot analysis. We observed that these compounds downregulated the expression of LPS-induced NF-κB and pERK 1/2 in RAW 264.7 cells. Our results demonstrate that serratane triterpenoids isolated from L. clavatum may be used as potential candidates for treating inflammatory bowel disease (IBD) due to their anti-inflammatory effects.

Effect of the Sphingosine Kinase 1 Selective Inhibitor, PF543 on Dextran Sodium Sulfate-Induced Colitis in Mice

Ulcerative colitis (UC) is a chronic relapsing inflammatory bowel disease, which often affects colon or rectum or both. It is now well recognized that sphingosine kinases-1/sphingosine-1-phosphate (S1P) signaling may have a very significant potential as targets for therapeutic intervention in UC. Compared with the pure dextran sodium sulfate group, administration of PF543 significantly reduced clinical symptoms with less weight loss, diarrhea, and shortening of the colon. The severity of colitis was improved with reduced disease activity index and degree of histological damage in colon. Moreover, treatment with PF543 not only decreased S1P but also inhibited mRNA expression of proinflammatory factors such as interleukin (IL)-1β and IL-6. This suggests that PF543 might exhibit an anti-inflammatory function against colitis through inhibition of expression of proinflammatory factors.

Interleukin 1 is a key driver of inflammatory bowel disease-demonstration in a murine IL-1Ra knockout model

Interleukin 1 (IL-1) is an important mediator of inflammation and tissue damage in inflammatory bowel disease (IBD). The balance between IL-1 and IL-1Ra as a natural inhibitor plays a vital role in a variety of diseases. Here, we investigated whether changes seen during IBD are induced spontaneously in mice lacking a functional IL-1rn gene. Histological staining was performed on the jejunum and ileum of BALB/c IL-1rn+/+ and IL-1rn-/- mice to characterize crypt-villus height, villus width, and number of goblet cells per villus. Pro-inflammatory cytokines, immune cell infiltration and matrix-degrading enzymes, together with the production of intestinal enzymes and the integrity of tight and adherent junction proteins were determined using immunohistochemistry. In the small intestine of BALB/c IL-1rn-/- mice the villus heights were significantly reduced; and in the ileum this was accompanied by a decrease in villi width. There was also an increase in goblet cell number and mucin production compared to wild-type mice. IL-1α and IL-1β immunopositivity were increased, whilst IL-1R1 expression was decreased in IL-1rn-/- mice. IL-15 and TNFα were also increased in older IL-1rn-/- mice. Increased polymorphonuclear and macrophage infiltration were seen in IL-1rn-/- mice, whilst expression of matrix-degrading enzymes and digestive enzymes were unchanged, except for dipeptidyl peptidase IV which was increased in younger IL-1rn-/- mice compared to wild type mice. The expression of tight and adhesion junctions were also dramatically decreased in IL-1rn-/- mice. In conclusion, IL-1rn-/- mice developed spontaneous abnormalities which displayed features associated with IBD, demonstrating a clear role for IL-1 in IBD.

Disruption of FOXP3-EZH2 Interaction Represents a Pathobiological Mechanism in Intestinal Inflammation

Background & Aims

Forkhead box protein 3 (FOXP3)+ regulatory T cell (Treg) dysfunction is associated with autoimmune diseases; however, the mechanisms responsible for inflammatory bowel disease pathophysiology are poorly understood. Here, we tested the hypothesis that a physical interaction between transcription factor FOXP3 and the epigenetic enzyme enhancer of zeste homolog 2 (EZH2) is essential for gene co-repressive function.

Methods

Human FOXP3 mutations clinically relevant to intestinal inflammation were generated by site-directed mutagenesis. T lymphocytes were isolated from mice, human blood, and lamina propria of Crohn's disease (CD) patients and non-CD controls. We performed proximity ligation or a co-immunoprecipitation assay in FOXP3-mutant+, interleukin 6 (IL6)-treated or CD-CD4+ T cells to assess FOXP3-EZH2 protein interaction. We studied IL2 promoter activity and chromatin state of the interferon γ locus via luciferase reporter and chromatin-immunoprecipitation assays, respectively, in cells expressing FOXP3 mutants.

Results

EZH2 binding was abrogated by inflammatory bowel disease-associated FOXP3 cysteine 232 (C232) mutation. The C232 mutant showed impaired repression of IL2 and diminished EZH2-mediated trimethylation of histone 3 at lysine 27 on interferon γ, indicative of compromised Treg physiologic function. Generalizing this mechanism, IL6 impaired FOXP3-EZH2 interaction. IL6-induced effects were reversed by Janus kinase 1/2 inhibition. In lamina propria-derived CD4+T cells from CD patients, we observed decreased FOXP3-EZH2 interaction.

Conclusions

FOXP3-C232 mutation disrupts EZH2 recruitment and gene co-repressive function. The proinflammatory cytokine IL6 abrogates FOXP3-EZH2 interaction. Studies in lesion-derived CD4+ T cells have shown that reduced FOXP3-EZH2 interaction is a molecular feature of CD patients. Destabilized FOXP3-EZH2 protein interaction via diverse mechanisms and consequent Treg abnormality may drive gastrointestinal inflammation.

TNFα inhibitors exacerbate Mycobacterium paratuberculosis infection in tissue culture: a rationale for poor response of patients with Crohn's disease to current approved therapy

Background The role of Mycobacteriumavium subspecies paratuberculosis (MAP) in Crohn’s disease (CD) is increasingly accepted as evident by detection of the bacteria in the blood and intestinal tissue from patients with CD, and by supporting data from several open-label anti-MAP treatment studies. Tumour necrosis factor alpha (TNFα) monoclonal antibodies (anti-TNFα) have been widely used for CD treatment. Despite the short-term benefit of anti-TNFα in controlling CD symptoms, most patients suffer from detrimental adverse effects, including higher susceptibility to mycobacterial infections. Methods We investigated the effect of recombinant cytokines and anti-TNFα therapeutics on macrophages infected with clinical MAP strain isolated from CD patient blood. MAP viability was measured in macrophages pulsed with PEGylated and non-PEGylated anti-TNFα monoclonal antibodies at concentrations 0 to 50 µg/mL and with rTNFα, rIL-6, rIL-12, rIL-23 and IFNγ at a final concentration of 1000 U/mL. Expression of proinflammatory cytokines was measured by RT-PCR following MAP infection.

Results Both PEGylated and non-PEGylated forms of anti-TNFα increased MAP viability by nearly 1.5 logs. rIL-6 and rIL-12 induced MAP viability at 5.42±0.25 and 4.79±0.14 log CFU/mL, respectively. In contrast, rTNFα reduced MAP survival in infected macrophages by 2.63 logs. Expression of TNFα, IL-6 and IL-12 was upregulated threefold following MAP or M. tuberculosis infection compared with other bacterial strains (p<0.05), while expression of IL-23 and IFNγ was not significant after MAP infection.

Conclusion The data indicate MAP-positive patients with CD receiving anti-TNFα treatment could result in favourable conditions for MAP infection, which explains the poor response of many patients with CD to anti-TNFα therapy.

Pien Tze Huang ameliorates DSS‑induced colonic inflammation in a mouse colitis model through inhibition of the IL‑6/STAT3 pathway

Interleukin‑6 (IL‑6)/signal transducer and activator of transcription 3 (STAT3) pathway plays essential roles in the development of inflammatory diseases including ulcerative colitis (UC). Therefore, suppression of IL‑6/STAT3 signaling provides a promising therapeutic strategy in UC. Pien Tze Huang (PZH), a well‑known traditional Chinese formula, has been used in China and Southeast Asia for centuries as a folk remedy for various inflammatory diseases. However, the molecular mechanisms of its anti‑inflammatory effects remain to be elucidated. In the present study, we generated a mouse colitis model by using dextran sulfate sodium (DSS) and evaluated the therapeutic efficacy of PZH against UC by observing the clinical manifestations. We found that PZH obviously alleviated DSS‑induced colitis symptoms, including body weight loss, rectal bleeding and stool consistency. In addition, administration of PZH profoundly prevented DSS‑induced colon shortening, and ameliorated colonic histopathological changes such as mucosal ulceration, infiltration of inflammatory cells, crypt distortion and hyperplastic epithelium. Moreover, PZH markedly inhibited the serum level of the inflammatory biomarker serum amylase A (SAA) in UC mice. Furthermore, PZH treatment significantly inhibited DSS‑induced expression of IL‑6 in colon tissues. Finally, the increased phosphorylation level of STAT3, induced either by DSS in experimental mice or by IL‑6 in the differentiated human colorectal carcinoma cells, was significantly suppressed by PZH. These results suggest that the inhibition of IL‑6/STAT3 signaling is a potential mechanism by which PZH is used in the treatment of UC.

Modulation of VIPergic phenotype of enteric neurons by colonic biopsy supernatants from patients with inflammatory bowel diseases: Involvement of IL-6 in Crohn's disease

BACKGROUND

Neuroplastic changes in the enteric nervous system (ENS) observed during IBD might participate in physiopathological processes. Vasoactive intestinal polypeptide has been shown to be involved in intestinal inflammation and barrier functions. We aimed to investigate the modulation of VIP expression in colonic biopsies of IBD patient, the ability of soluble factors from biopsies to reproduce in vitro these modulations and identify soluble factors responsible.

METHODS

VIP and cytokines mRNA expressions were assessed in colonic biopsies of healthy subjects (HS) and IBD patients from inflamed (I) and non-inflamed areas (NI). Supernatants (SUP) of biopsies were applied to primary culture of ENS and VIP and cytokines mRNA expressions were assessed. The role of cytokines in SUP induced changes in VIP expression was evaluated.

KEY RESULTS

VIP mRNA expression was lower in biopsies of patients with Crohn's disease (CD) than Ulcerative Colitis (UC) but unchanged as compared to HS. VIP mRNA and protein expression were lower in primary culture of ENS incubated with SUP-CD than with SUP-UC. Furthermore, in CD but not UC, SUP-I reduced VIP expression in the ENS as compared to SUP-NI. Next, IL-6 but not IL-5, IL-10, IL-17, IFN-γ or TNF-α reduced VIP expression in the ENS. Finally, in CD, SUP-I incubated with anti-IL-6 antibody increased VIP expression as compared to SUP-I alone.

CONCLUSIONS & INFERENCES

Mucosal soluble factors from IBD induce VIP neuroplastic changes in the ENS. IL-6 was identified as a putative soluble factor responsible in part for changes in VIP expression in CD.

Crohn's Disease and Ulcerative Colitis Show Unique Cytokine Profiles

Introduction

Networks of cytokines have been implicated in both forms of inflammatory bowel disease (IBD): Crohn’s disease (CD) and ulcerative colitis (UC). While CD has associated with T-helper type 1 (Th1) immune responses, UC shows Th2 patterns. Recent studies reported that the inflamed intestinal regions in both CD and UC are significantly infiltrated with a newly described set of T helper, the Th17 cells. These cells have unique cytokine responses. These findings prompted us to further explore the cytokine profiles of CD and UC with a special focus on the Th2 and Th17 related mediators.

Methods

Cytokine transcripts were compared using real-time polymerase chain reaction (PCR) in both inflamed and non-inflamed mucosal specimens from patients with active CD (n=35) or UC (n=20) and without CD or UC (Control, n=54).

Results

In both CD and UC, interleukin (IL)-12 (p40), IL-18, IL-21 and IL-27 transcript levels were higher than in Control. The highest levels of cytokines were found in the diseased areas of CD and UC with only one exception; IL-12 (p40) in CD was more up-regulated in the non-diseased areas compared to diseased CD and Control specimens. CD samples but not UC specimens showed significant IL-17, IL-23, and IL-32 mRNA expression indicating a trend toward Th17 responses. In UC, however, IL-5, IL-13, IL-15 and IL-33 mRNA levels were significantly increased when compared to both CD and Control.

Conclusions

The unique patterns of cytokine networks can help us to better understand the differential expression of their characteristic pathophysiology. In addition, the pharmacological regulation of these small molecules may hold promise to more effective and personalized therapies.

Novel Targeted Therapies for Inflammatory Bowel Disease

Our growing understanding of the immunopathogenesis of inflammatory bowel disease (IBD) has opened new avenues for developing targeted therapies. These advances in treatment options targeting different mechanisms of action offer new hope for personalized management. In this review we highlight emerging novel and easily administered therapeutics that may be viable candidates for the management of IBD, such as antibodies against interleukin 6 (IL-6) and IL-12/23, small molecules including Janus kinase inhibitors, antisense oligonucleotide against SMAD7 mRNA, and inhibitors of leukocyte trafficking to intestinal sites of inflammation (e.g., sphingosine 1-phosphate receptor modulators). We also provide an update on the current status in clinical development of these new classes of therapeutics.

Targeting interleukins for the treatment of inflammatory bowel disease-what lies beyond anti-TNF therapy?

: Inflammatory bowel disease accounts for significant patient morbidity in the Western world. Several immunosuppressive therapies are available but are associated with potential significant adverse effects. In addition, there remains a cohort of patients with refractory or relapsing disease. Therefore, the search for novel therapeutic agents continues. In this review, we evaluate the role of a number of designated cytokines that are candidates in the pathogenesis of inflammatory bowel disease and discuss how their manipulation has been explored as a therapeutic strategy for this disease. The interleukins (ILs) chosen for discussion reflect those that currently show most promise as future therapeutic targets, as well as discussing the role of some of the most recently identified ILs, such as IL-27, IL-33, IL-35, and IL-22, in this context.

Fatty acid synthase inhibitor C75 ameliorates experimental colitis

Abnormalities of lipid metabolism through overexpression of fatty acid synthase (FASN), which catalyzes the formation of long-chain fatty acids, are associated with the development of inflammatory bowel disease (IBD). C75 is a synthetic α-methylene-γ-butyrolactone compound that inhibits FASN activity. We hypothesized that C75 treatment could effectively reduce the severity of experimental colitis. Male C57BL/6 mice were fed 4% dextran sodium sulfate (DSS) for 7 d. C75 (5 mg/kg body weight) or dimethyl sulfoxide (DMSO) (vehicle) was administered intraperitoneally from d 2 to 6. Clinical parameters were monitored daily. Mice were euthanized on d 8 for histological evaluation and measurements of colon length, chemokine, cytokine and inflammatory mediator expression. C75 significantly reduced body weight loss from 23% to 15% on d 8, compared with the vehicle group. The fecal bleeding, diarrhea and colon histological damage scores in the C75-treated group were significantly lower than scores in the vehicle animals. Colon shortening was significantly improved after C75 treatment. C75 protected colon tissues from DSS-induced apoptosis by inhibiting caspase-3 activity. Macrophage inflammatory protein 2, keratinocyte-derived chemokine, myeloperoxidase activity and proinflammatory cytokines (tumor necrosis factor-α, interleukin [IL]-1β and IL-6) in the colon were significantly downregulated in the C75-treated group, compared with the vehicle group. Treatment with C75 in colitis mice inhibited the elevation of FASN, cyclooxygenase-2 and inducible nitric oxide synthase expression as well as IκB degradation in colon tissues. C75 administration alleviates the severity of colon damage and inhibits the activation of inflammatory pathways in DSS-induced colitis. Thus, inhibition of FASN may represent an attractive therapeutic potential for treating IBD.

Suppression of dextran sulfate sodium-induced colitis in mice by radon inhalation

The enhanced release of reactive oxygen species from activated neutrophils plays important role in the pathogenesis of inflammatory bowel disease. We previously reported that radon inhalation activates antioxidative functions in various organs of mice. In this study, we examined the protective effects of radon inhalation on dextran sulfate sodium- (DSS) induced colitis in mice which were subjected to DSS for 7 days. Mice were continuously treated with air only (sham) or radon at a concentration of 2000 Bq/m³ from a day before DSS administration to the end of colitis induction. In the results, radon inhalation suppressed the elevation of the disease activity index score and histological damage score induced by DSS. Based on the changes in tumor necrosis factor-alpha in plasma and myeloperoxidase activity in the colon, it was shown that radon inhalation suppressed DSS-induced colonic inflammation. Moreover, radon inhalation suppressed lipid peroxidation of the colon induced by DSS. The antioxidant level (superoxide dismutase and total glutathione) in the colon after DSS administration was significantly higher in mice treated with radon than with the sham. These results suggested that radon inhalation suppressed DSS-induced colitis through the enhancement of antioxidative functions in the colon.

The role of cytokines in inflammatory bowel disease

Cytokines play an important role in the development and persistence of the inflammatory lesions seen in Crohn's disease and ulcerative colitis. This review discusses the current thinking of the role of cytokines in chronic intestinal inflammation including the involvement of immunoregulatory cytokines within the Th1 and Th2 subsets.

Resveratrol has antiinflammatory and antifibrotic effects in the peptidoglycan-polysaccharide rat model of Crohn's disease

BACKGROUND

Resveratrol has antiinflammatory and antifibrotic effects. Resveratrol decreases proliferation and collagen synthesis by intestinal smooth muscle cells. We hypothesized that resveratrol would decrease inflammation and fibrosis in an animal model of Crohn's disease.

METHODS

Peptidoglycan-polysaccharide (PG-PS) or human serum albumin (HSA) was injected into the bowel wall of Lewis rats at laparotomy. Resveratrol or vehicle was administered daily by gavage 1-27 days postinjection. On day 28, gross abdominal and histologic findings were scored. Cecal collagen content was measured by colorimetric analysis of digital images of trichrome-stained sections. Cecal levels of procollagen, cytokine, and growth factor mRNAs were determined.

RESULTS

PG-PS-injected rats (vehicle-treated) developed more fibrosis than HSA-injected rats by all measurements: gross abdominal score (P < 0.001), cecal collagen content (P = 0.04), and procollagen I and III mRNAs (P ≤ 0.0007). PG-PS-injected rats treated with 40 mg/kg resveratrol showed a trend toward decreased gross abdominal score, inflammatory cytokine mRNAs, and procollagen mRNAs. PG-PS-injected rats treated with 100 mg/kg resveratrol had lower inflammatory cytokine mRNAs (IL-1β [3.50 ± 1.08 vs. 10.79 ± 1.88, P = 0.005], IL-6 [17.11 ± 9.22 vs. 45.64 ± 8.83, P = 0.03], tumor necrosis factor alpha (TNF-α) [0.80 ± 0.14 vs. 1.89 ± 0.22, P = 0.002]), transforming growth factor beta 1 (TGF-β1) mRNA (2.24 ± 0.37 vs. 4.06 ± 0.58, P = 0.01), and histologic fibrosis score (6.4 ± 1.1 vs. 9.8 ± 1.0; P = 0.035) than those treated with vehicle. There were trends toward decreased gross abdominal score and decreased cecal collagen content. Procollagen I, procollagen III, and IGF-I mRNAs also trended downward.

CONCLUSIONS

Resveratrol decreases inflammatory cytokines and TGF-β1 in the PG-PS model of Crohn's disease and demonstrates a promising trend in decreasing tissue fibrosis. These findings may have therapeutic applications in inflammatory bowel disease.

Neutrophil-dependent oxidative stress in ulcerative colitis

Neutrophil accumulation within epithelial crypts and in the intestinal mucosa directly correlates with clinical disease activity and epithelial injury in ulcerative colitis (UC). Current advances have defined the mechanisms by which neutrophils are activated or migrate across mucosal epithelia. A better understanding of this process will likely provide new insights into novel treatment strategies for UC. Especially, activated neutrophils produce reactive oxygen and nitrogen species within intestinal mucosa, which induce oxidative stress. In clinically, we have succeeded to develop a novel granulocytes adsorptive apheresis therapy for UC. In this article, we discuss current advances to define the role of neutrophils-dependent oxidative stress in UC.

Interleukins, from 1 to 37, and interferon-γ: receptors, functions, and roles in diseases

Advancing our understanding of mechanisms of immune regulation in allergy, asthma, autoimmune diseases, tumor development, organ transplantation, and chronic infections could lead to effective and targeted therapies. Subsets of immune and inflammatory cells interact via ILs and IFNs; reciprocal regulation and counter balance among T(h) and regulatory T cells, as well as subsets of B cells, offer opportunities for immune interventions. Here, we review current knowledge about ILs 1 to 37 and IFN-γ. Our understanding of the effects of ILs has greatly increased since the discoveries of monocyte IL (called IL-1) and lymphocyte IL (called IL-2); more than 40 cytokines are now designated as ILs. Studies of transgenic or knockout mice with altered expression of these cytokines or their receptors and analyses of mutations and polymorphisms in human genes that encode these products have provided important information about IL and IFN functions. We discuss their signaling pathways, cellular sources, targets, roles in immune regulation and cellular networks, roles in allergy and asthma, and roles in defense against infections.

Inflammatory bowel disease

This review focuses on the prominent etiological and pathogenetic aspects of inflammatory bowel disease (IBD), with particular attention being paid to the mucosal immune response to commensal micro-organisms in health and disease. Pathogenetic implications for target therapy will also be discussed. The clinical presentation, diagnostic aspects, and currently recommended therapeutic options for the two main types of IBD are also taken into consideration, including manifestations of these conditions in the oral cavity.

Th17-cytokine blockers as a new approach for treating inflammatory bowel disease

Anti-cytokine therapies, including the anti-TNF-α antibody-based therapies, have largely transformed the management of patients with inflammatory bowel diseases (IBD). However, benefit is seen in nearly 50% of patients, and response can wane with time. Moreover, patients treated with anti-TNF-α antibodies can develop severe side-effects and new immune-mediated diseases. Therefore enormous effort has been made by the research community to elucidate new inflammatory networks in the IBD tissue and to develop novel anti-cytokine compounds, which may act in patients who do not respond to or cannot receive anti-TNF-α therapies. In this article we review the available data supporting the pathogenic role of Th17 cytokines in IBD, and discuss whether and how inhibitors of these inflammatory mediators may enter into the therapeutic armamentarium of IBD.

Dietary β-glucan regulates the levels of inflammatory factors, inflammatory cytokines, and immunoglobulins in interleukin-10 knockout mice

β-Glucan is known to have anti-inflammatory properties, and several studies have demonstrated the beneficial effects of dietary β-glucan on inflammatory bowel disease (IBD). However, it is unknown how β-glucan mediates its protective effects on IBD. Therefore, we used a well-established mouse model for IBD, interleukin (IL)-10(-/-) mice, to explore the protective effects of β-glucan on IBD-like symptoms caused by IL-10 deficiency. The mice were divided into two groups: IL-10(-/-) and IL-10(-/-) + β-glucan treatment groups. IL-10(-/-) mice treated with dietary β-glucan exhibited less inflammation within the colon. The levels of immunoglobulins A and E were lower in the serum, spleen, mesenteric lymph nodes, and Peyer's patches in the IL-10(-/-) mice compared with the IL-10(-/-) + β-glucan mice. Also, the expression of pro-inflammatory cytokines was lower in the IL-10(-/-) + β-glucan mice compared with the IL-10(-/-) mice. Histological analysis also revealed that administration of dietary β-glucan in IL-10(-/-) mice reduced colonic tissue damage. Finally, the expression of the pro-inflammatory cytokine tissue necrosis factor-α was significantly lower with dietary β-glucan treatment in IL-10(-/-) mice. In conclusion, dietary β-glucan reduces the inflammation associated with IBD caused by IL-10 deficiency.

Potential impact of B cells on T cell function in multiple sclerosis

Multiple sclerosis is a chronic debilitating autoimmune disease of the central nervous system. The contribution of B cells in the pathoetiology of MS has recently been highlighted by the emergence of rituximab, an anti-CD20 monoclonal antibody that specifically depletes B cells, as a potent immunomodulatory therapy for the treatment of MS. However, a clearer understanding of the impact B cells have on the neuro-inflammatory component of MS pathogenesis is needed in order to develop novel therapeutics whose affects on B cells would be beneficial and not harmful. Since T cells are known mediators of the pathology of MS, the goal of this review is to summarize what is known about the interactions between B cells and T cells, and how current and emerging immunotherapies may impact B-T cell interactions in MS.

Expression, localization and systemic concentration of vascular endothelial growth factor (VEGF) and its receptors in patients with ulcerative colitis

Vascular endothelial grow factor (VEGF) promotes angiogenesis by activating the specific receptors KDR and Flt-1. We investigate the expression of genes encoding VEGF and its receptors KDR and Flt- 1 by RT-QPCR reaction using Quanti Tect SYBR Green RT-PCR in patients with active and inactive ulcerative colitis (UC) and control subjects. The localization and level of VEGF protein and its receptors protein in intestinal tissue were estimated by immunohistochemistry. VEGF concentration in serum and plasma was determined by ELISA. We found a significant increase of VEGF gene expression and increase expression of genes encoding receptor Flt-1 in patients with active UC when compared with controls, but KDR was present in trace amount. VEGF and Flt-1 proteins were colocalized in enterocytes as well as in endothelium and muscularis layer of the intestine. The specific staining reaction for VEGF protein as well as for Flt-1 protein was significantly higher in active UC compared with controls. Serum level of VEGF was significantly higher in active UC patients as compared with inactive UC patients as well as with controls. The plasma VEGF level was found to be significantly higher in active UC patients as compared with controls. The increase of gene expression as well as protein level for VEGF and its receptor in UC - inflamed colon, and VEGF action via Flt-1 receptor may have a functional role in UC. Increased VEGF levels in both serum and plasma in active UC patients may reflect VEGF overexpression in intestinal inflammatory tissue.

Dietary pectin regulates the levels of inflammatory cytokines and immunoglobulins in interleukin-10 knockout mice

Pectin has protective, anti-inflammatory effects on inflammatory bowel disease (IBD), but the exact mechanism is unknown. Therefore, we investigated the immunological effect of dietary pectin in IL-10(-/-) mice, a murine model for IBD. Cytokine expression, CD4(+) and CD8(+) T cell populations, and immunoglobulin secretion were observed in three groups of mice: normal (BALb/c), IL-10(-/-), and IL-10(-/-) treated with pectin. Pectin treatment reduced expression of TNF-α and GATA-3, an important transcription factor for the Th2 immune response. These mice also expressed lower levels of IgE in the spleen and Peyer's patches (PP) and lower IgG and IgM expression in PP. Interestingly, IL-10 deficiency resulted in lower CD4(+) and CD8(+) populations in the spleen, mesenteric lymph node (MLN), and PP; however, pectin counteracted these declines in the MLN and PP. Therefore, dietary pectin downregulates the inflammatory response in the colon by moderating the production of proinflammatory cytokines and immunoglobulins.

Anti-oxidant effects of resveratrol on mice with DSS-induced ulcerative colitis

BACKGROUND AND AIMS

Oxidant/antioxidant balance is suggested to be an important factor for the recurrence and progression of ulcerative colitis (UC). The aim of the study is to investigate the potential protective role of resveratrol (Res) against dextran sodium sulfate (DSS)-induced oxidative damage in colon of mice with UC.

METHODS

UC was induced in mice by oral administration of synthetic DSS (molecular weight 5000) for 7 days. Mice were divided into normal group, colitis control group, low-dose Res-treated group (RLD-treated group), and high-dose Res-treated group (RHD-treated group). Inhibitory effects of concomitant treatment with Res were assessed daily using a Disease Activity Index (DAI) and severity of histological changes. MDA, MPO, SOD and GSH-PX activity of colonic tissue were determined in colon samples by chemical colorimetry. TNF-alpha, IL-8, IFN-gamma, p22(phox) and gp91(phox) expression levels were detected using quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR), ELISA, and Western blot analysis.

RESULT

Administration of Res significantly inhibited the severity of UC compared to the colitis control group. Colonic tissue MDA and MPO activities decreased significantly in Res-treated groups compared to colitis control groups. Furthermore, colonic tissue SOD and GSH-Px activities increased significantly in Res-treated groups compared to colitis control groups. The expression levels of TNF-alpha, IL-8, IFN-gamma, p22(phox), and gp91(phox) also decreased significantly in the Res-treated group compared to the colitis control group.

CONCLUSIONS

Oral administration of Res exerts marked inhibitory effects on UC in mice. Resveratrol may play an important role in preventing DSS-induced oxidative damage.

Potential for amino acids supplementation during inflammatory bowel diseases

The pathophysiology of inflammatory bowel diseases (IBDs) is multifactorial and involves interactions of gut luminal content with mucosal barrier and especially immune cells. Malnutrition is a frequent issue during IBD flares, especially in Crohn's disease (CD) patients, and nutritional support is frequently used to treat malnutrition but also in an attempt to modulate intestinal inflammation. The use of oral or enteral nutrition intervention in IBDs may be effective, alone or in combination with drugs, to achieve and maintain remission. However, standard diets are less effective than new-generation biotherapies and could be improved by supplementation with specific immunomodulatory amino acids. Experimental studies evaluating glutamine, the preferential substrate for enterocytes, are promising. Some clinical studies with oral glutamine in CD are until now disappointing, but new formulations and targeting could enhance glutamine efficacy at the site of mucosal lesions. The role of arginine, involved in nitric oxide and polyamines synthesis, still remains debated. However, the effects of these amino acids in IBD have been poorly documented in humans. Other candidates like glycine, cysteine, histidine, or taurine should also be evaluated in the future.

NF-kappaB p65 antisense oligonucleotides may serve as a novel molecular approach for the treatment of patients with ulcerative colitis

BACKGROUND

Activation of nuclear factor-kappa B (NF-kappaB), which controls transcription of various proinflammatory cytokine genes, has been shown to play a critical role in the pathogenesis of ulcerative colitis (UC). The aim of this study was to investigate if NF-kappaB p65 antisense oligonucleotides may affect the expression of NF-kappaB p65 and cytokines in lamina propria mononuclear cells (LPMCs) from patients with UC.

METHODS

LPMCs, which were isolated from intestinal mucosal biopsy specimens from patients with UC, were cultured with or without NF-kappaB p65 antisense oligonucleotides, missense oligonucleotides and dexamethasone. NF-kappaB p65 expression was determined by Western blot analysis. The expression of cytokine mRNA was studied by reverse transcription-polymerase chain reaction (RT-PCR). Cytokine levels were measured by enzyme-linked immunosorbent assay.

RESULTS

NF-kappaB p65 antisense oligonucleotides resulted in downregulation of NF-kappaB p65 expression, blocked the expression of IL-1beta mRNA and IL-8 mRNA, and strikingly reduced the production of IL-1beta and IL-8. These effects were greater than those of dexamethasone in cultured LPMCs from patients with UC (p <0.05).

CONCLUSIONS

Application of NF-kappaB p65 antisense oligonucleotides may serve as a novel molecular approach for the treatment of patients with UC.

Combined glutamine and arginine decrease proinflammatory cytokine production by biopsies from Crohn's patients in association with changes in nuclear factor-kappaB and p38 mitogen-activated protein kinase pathways

Glutamine (Gln) and arginine (Arg) are conditionally essential amino acids with immunomodulatory properties. The aim of the study was to assess the effects of Gln and Arg alone or in combination on cytokine release by cultured colonic biopsies from patients with active Crohn's disease (CD). Ten consecutive patients [mean (range) age 26 (18-39) y] with active colonic CD (mean CD activity index: 383.7 +/- 129.8) were prospectively included in the study. Eight colonic biopsies were obtained via a colonoscopy and incubated during 18 h with low (physiological) or high (pharmacological) doses of Arg (0.1 or 2 mmol/L designated as Arg(low) or Arg(high), respectively) and Gln (0.6 or 10 mmol/L designated as Gln(low) or Gln(high), respectively). The concentrations of cytokines [interleukin (IL)-4, IL-10, IL-8, IL-6, tumor necrosis factor-alpha (TNFalpha), IL-1beta, interferon-gamma) were assessed by ELISA, and nitric oxide (NO) production was evaluated by Griess assay. Nuclear factor (NF)-kappaB p65 subunit, inhibitor of NFkappaB-alpha, and p38 mitogen-activated protein kinase (MAPK) were assessed by immunoblotting. Arg(high)/Gln(high) decreased the production of TNFalpha, IL-1beta, IL-8, and IL-6 (each P < 0.01). Arg(low)/Gln(high) decreased IL-6 and IL-8 production (both P < 0.01), whereas Arg(high)/Gln(low) did not affect cytokine and NO production. Arg(low)/Gln(high) and Arg(high)/Gln(high) decreased NF-kappaB p65 subunit expression, whereas p38 MAPK was decreased only by Arg(high)/Gln(high). Combined pharmacological doses of Arg and Gln decreased TNFalpha and the main proinflammatory cytokines release in active colonic CD biopsies via NF-kappaB and p38 MAPK pathways. These results could be the basis of prospective studies evaluating the effects of enteral supply of combined Arg and Gln during active CD.

Dietary Lactoferrin Does Not Prevent Dextran Sulfate Sodium Induced Murine Intestinal Lymphocyte Death

Dextran sulfate sodium (DSS) induced intestinal inflammation is characterized by pronounced mucosal and epithelial cell damage. Bovine lactoferrin (bLf), a common dietary protein, influences inflammatory cytokines and intestinal lymphocyte (IL) apoptosis. The objectives of this study were to determine if 1) DSS induces IL necrotic or apoptotic death, 2) dietary bLf affects DSS induced IL death and 3) bLf alters cytokine profiles during DSS induced inflammation. Female C57BL/6 mice were randomized to 2% or 0% bLf diets for 12 d and within diets to 5% or 0% DSS in the drinking water for 4 d after which intestinal histology, IL number, IL apoptosis/necrosis, IL phenotypes, protein levels of pro-inflammatory cytokine (TNF-α) and transcription factor (NFκB), apoptotic (caspase 3, Bax) proteins, anti-inflammatory cytokine (IL-10) and anti-apoptotic (Bcl-2) protein in IL were evaluated. DSS treatment resulted in shortened intestinal length, decreased body weight and widespread mucosal damage as well as increased IL death as determined by a decreased percentage of viable (PI−/ANN−, P < 0.005) and increased percentage of necrotic/late apoptotic (PI+/ ANN+, P < 0.05) and necrotic (PI+/ANN−, P < 0.05) IL. DSS exposure increased caspase 3 ( P < 0.05) and decreased Bcl-2 ( P < 0.01) protein levels in mouse IL. Dietary bLf did not influence these cell death outcome measures. However, bLf reduced protein levels of the pro-inflammatory transcription factor, NFκB, in IL ( P < 0.05) and was associated with a 34%, albeit non-significant, reduction in TNF-α relative to non-bLf fed mice. DSS treatment increased apoptosis and necrosis of mouse IL and elevated pro-apoptotic and reduced anti-apoptotic protein levels in these cells. Dietary bLf did not influence necrosis or apoptosis of IL but may provide limited protection in the intestine by affecting the pro-inflammatory transcription factor NFκB, and potentially, cytokine expression.

New therapeutic strategies for treatment of inflammatory bowel disease

Although the precise etiology of inflammatory bowel disease (IBD) still remains unclear, considerable progress has been made in the identification of cytokine-mediated signaling pathways involved in the inflammatory process. Recent data have clearly shown that these pathways induce augmented intestinal T-cell activation and thus resistance to apoptosis, which is a central process in disease pathogenesis, as it impairs mucosal homeostasis. Therefore, novel therapeutic strategies aim at restoring activated effector T-cell susceptibility to apoptosis in the gut, based on a pathophysiological rationale. This development is best exemplified by the emergence of agents that target the TNF pathway, IL-6 trans-signaling, and the IL-12/IL-23 pathway. These compounds give hope for the development of new strategies aiming at more effective and less toxic therapies for IBD.

Influence of genetics on disease susceptibility and progression

For many chronic diseases, the influence of genetics is complex and phenotypes do not conform to simple Mendelian patterns of inheritance. Discussed here are two types of genetic influences on healthy aging. The first involves variation in the gene sequence itself and how this may influence disease susceptibility, progression, and severity, interacting with other recognized risk factors. The second involves epigenetic regulatory mechanisms that may potentially provide insight into how environmental influences affect the expressed genome, thus improving our understanding of the genetic mechanisms underlying multifactorial diseases. The interleukin-1 family of cytokines can be used to illustrate how genetic sequence variation may affect such diseases. This cytokine family plays a key role in mediating inflammation, which is now understood to be a central component of a growing number of chronic diseases. Recent work has revealed many sequence variations in the regulatory DNA of genes encoding important members of the interleukin-1 family, and these variations are associated with differential effects on the inflammatory response. The interactions of environmental factors with both DNA sequence variations and epigenetic modifications are likely to determine the phenotypes of multifactorial diseases of aging as well as the phenotype of healthy aging.

Molecular fingerprints of neutrophil-dependent oxidative stress in inflammatory bowel disease

Neutrophil accumulation within epithelial crypts and in the intestinal mucosa directly correlates with clinical disease activity and epithelial injury in inflammatory bowel disease (IBD). Current advances have defined the mechanisms by which neutrophils are activated or migrate across endothelial and mucosal epithelial cells. A better understanding of this process will likely provide new insights into novel treatment strategies for IBD. Especially, activated neutrophils produce reactive oxygen and nitrogen species and myeloperoxidase within intestinal mucosa, which induce oxidative stress. Posttranslational modification of proteins generated by these reactive species serves as a "molecular fingerprint" of protein modification by lipid peroxidation-, nitric oxide-, and myeloperoxidase-derived oxidants. Measurement of these modified proteins may serve both as a quantitative index of oxidative stress and an important new biological marker of clinical relevance to IBD. We have succeeded in the clinical development of a novel granulocyte adsorptive apheresis therapy for IBD. In this review, we discuss current advances in defining the role of neutrophil-dependent oxidative stress in IBD.

HETEs enhance IL-1-mediated COX-2 expression via augmentation of message stability in human colonic myofibroblasts

Proinflammatory cytokines and eicosanoids are central players in intestinal inflammation. IL-1, a key cytokine associated with intestinal mucosal inflammation, induces COX-2 expression in human colonic myofibroblasts (CMF) and increased prostaglandin E(2) secretion is associated with inflammatory bowel disease (IBD) and colorectal cancer (CRC). We have previously demonstrated that IL-1alpha-induced cyclooxygenase-2 (COX-2) expression is the result of NF-kappaB- and ERK-mediated transcription, as well as COX-2 message stabilization, which depends on p38, MAPKAPK-2 (MK-2) and human antigen R (HuR) RNA binding protein activation. Lipoxygenase (LOX)-derived hydroxyeicosatetraenoic acids (HETEs) are elevated in IBD and colonic adenomas and "cross talk" has been observed between the COX and LOX pathways. Since COX-2 expression is primarily in CMFs in colonic adenomas, we examined the impact of LOX metabolites, particularly HETEs, on IL-1alpha-induced COX-2 expression in human CMFs. Although 5(S)-, 12(R)-, and 15(S)-HETEs alone had little to no effect on COX-2 expression, they enhanced IL-1-mediated COX-2 expression 3.6 +/- 0.5-fold. Studies utilizing heterogeneous nuclear RNA amplification and 5,6-dichloro-beta-d-ribofuranosylbenzimidazole treatment were undertaken to measure COX-2 transcription and message stabilization, respectively. We found that HETEs enhanced IL-1-induced COX-2 mRNA levels in CMF as the result of increased p38, MK-2, and HuR activity, increasing message stability greater than that observed with IL-1 alone. Thus HETEs can act synergistically with IL-1alpha to induce COX-2 expression in human CMFs. HETEs may play a role in both colonic inflammation and in increasing the risk of CRC in IBD independently and via induction of COX-2-mediated prostaglandin secretion.

IL-1beta causes an increase in intestinal epithelial tight junction permeability

IL-1beta is a prototypical proinflammatory cytokine that plays a central role in the intestinal inflammation amplification cascade. Recent studies have indicated that a TNF-alpha- and IFN-gamma-induced increase in intestinal epithelial paracellular permeability may be an important mechanism contributing to intestinal inflammation. Despite its central role in promoting intestinal inflammation, the role of IL-1beta on intestinal epithelial tight junction (TJ) barrier function remains unclear. The major aims of this study were to determine the effect of IL-1beta on intestinal epithelial TJ permeability and to elucidate the mechanisms involved in this process, using a well-established in vitro intestinal epithelial model system consisting of filter-grown Caco-2 intestinal epithelial monolayers. IL-1beta (0-100 ng/ml) produced a concentration- and time-dependent decrease in Caco-2 transepithelial resistance. Conversely, IL-1beta caused a progressive time-dependent increase in transepithelial permeability to paracellular marker inulin. IL-1beta-induced increase in Caco-2 TJ permeability was accompanied by a rapid activation of NF-kappaB. NF-kappaB inhibitors, pyrrolidine dithiocarbamate and curcumin, prevented the IL-1beta-induced increase in Caco-2 TJ permeability. To further confirm the role of NF-kappaB in the IL-1beta-induced increase in Caco-2 TJ permeability, NF-kappaB p65 expression was silenced by small interfering RNA transfection. NF-kappaB p65 depletion completely inhibited the IL-1beta-induced increase in Caco-2 TJ permeability. IL-1beta did not induce apoptosis in the Caco-2 cell. In conclusion, our findings show for the first time that IL-1beta at physiologically relevant concentrations causes an increase in intestinal epithelial TJ permeability. The IL-1beta-induced increase in Caco-2 TJ permeability was mediated in part by the activation of NF-kappaB pathways but not apoptosis.

Effect of dietary lactoferrin on the immune functions and serum iron level of weanling piglets

A total of 90 weanling female pigs (Duroc x Landrace x Yorkshire) were used in a 30-d growth experiment to investigate the effect of lactoferrin (LF) on growth performance, immune function, and serum iron concentrations. The pigs were allocated on the basis of BW and litter to 3 dietary treatments in a randomized complete block design. The dietary treatments were: control group (basal diet), antibiotics group (basal diet + 20 mg/kg of flavomycin + 110 mg/kg of aureomycin), and LF group (basal diet + 1.0 g/kg of LF). There were 3 replicate pens per treatment, and pigs were grouped with 10 pigs per pen. Six pigs, randomly selected from each treatment (2 pigs/pen), were slaughtered for serum and spleen samples on d 15 and 30. Supplementation with LF improved the phytohemagglutinin (PHA)-stimulated peripheral lymphocyte proliferation by 36% (P < 0.01), increased concanavalin A (ConA)- and PHA-induced spleen lymphocyte proliferation by 332% (P < 0.01) and 258% (P < 0.01), enhanced serum IgG by 20% (P < 0.05), IgA by 13% (P < 0.05), IgM by 15% (P < 0.05), complement 4 (C4) by 29% (P < 0.05), IL-2 by 12% (P < 0.01), and serum iron values by 22% (P < 0.05) on d 15 compared with the control. Lactoferrin supplementation increased PHA-stimulated lymphocyte proliferation (P < 0.01), serum IgG by 16% (P < 0.05), IgA by 17% (P < 0.05), C4 by 11% (P < 0.05), IL-2 by 14% (P < 0.05), and serum iron values by 23% (P < 0.01), and decreased the diarrhea ratio (P < 0.05) relative to the control on d 30. Compared with the controls, supplementation with antibiotic increased ConA- and PHA-induced spleen lymphocyte proliferation (P < 0.05) on d 15, decreased the diarrhea ratio (P < 0.05), and increased the PHA-induced spleen lymphocyte proliferation (P < 0.05) and serum iron values (P < 0.01) on d 30. These results support the possible use LF as an immunostimulant to improve immune functions and strengthen host defenses and would seem to be a good method for defending weanling piglets from infections and weanling stress.

Interleukin-10 in the pathophysiology of inflammatory bowel disease: increased serum concentrations during the recovery phase

Using a specific enzyme-linked immunosorbent assay, IL-10 concentrations were measured in serum from 62 patients with ulcerative colitis (UC), 43 with Crohn's disease (CD), 25 with other colitides, and 44 normal control subjects. Serum IL-10 concentrations were increased in patients with active UC but not in those with active CD when compared with normal control subjects. A time course study showed that in patients with UC and CD, serum concentrations of IL-6 and C-reactive protein increased during the acute phase and returned to normal as patients go into remission. Notably, serum IL-10 concentrations increased during the phase of disease resolution and declined thereafter regardless of the treatment modality. Gel filtration analysis indicated that IL-10 circulated predominantly as a dimer. In conclusion, this study shows that serum IL-10 is increased during disease recovery in patients with inflammatory bowel disease, and may be a helpful marker in monitoring disease status.

Novel signal transduction pathways: analysis of STAT-3 and Rac-1 signaling in inflammatory bowel disease

Although the precise etiology of inflammatory bowel disease still remains unclear, considerable progress has been made in the identification of novel signal transduction pathways that elucidate the immunopathogenesis involved in the perpetuation of the inflammatory process. Augmented T cell resistance against apoptosis is regarded as a pivotal factor in the pathogenesis, as it impairs mucosal homeostasis and leads to unrestrained accumulation of activated T cells, which subsequently lead to the amplification of the inflammatory response. Therefore novel therapeutic strategies aim at restoring mucosal T cell susceptibility to apoptosis through targeting of signal transduction pathways that are elemental for augmented resistance of T lymphocytes against apoptosis. For example, a newly developed humanized anti-IL-6R monoclonal antibody that induces intestinal T cell apoptosis showed clinical efficacy in patients with active Crohn;s disease. Moreover, recent data that relate the immunosuppressive effects of azathioprine in inflammatory bowel disease to its apoptosis-inducing potential, have important implications for the design of a more specific therapeutic approach. The examination of these novel signal transduction pathways has elucidated the pathogenetic mechanisms involved in inflammatory bowel disease and gives hope for the development of new strategies that may result in a more effective and less toxic therapeutic procedure.

Increased cytokine transcripts in pouchitis reflect the degree of inflammation but not the underlying entity

BACKGROUND AND AIMS

After ileopouch anal anastomosis (IPAA), 10-40% of patients with ulcerative colitis (UC) but only 5% of patients with familial adenomatous polyposis (FAP) develop pouchitis. Immunoregulatory abnormalities might be of importance in the pathogenesis of the disease. Therefore, we characterized cytokine and chemokine transcripts in inflamed and non-inflamed pouches in patients with UC compared to those with FAP and Crohn's disease (CD).

PATIENTS AND METHODS

Mucosal biopsies were taken from 87 patients with IPAA [UC (n=70), CD (n=8) or FAP (n=9)]. Patients with active ileal CD (n=14), active UC (n=17) and non-inflammatory conditions (n=12) served as controls. The expression of 20 gene transcripts was quantified using real-time polymerase chain reaction.

RESULTS AND FINDINGS

Pro-inflammatory cytokines and chemokines are significantly increased in IPAA patients with acute pouchitis. This increase is independent of the underlying disease (UC or CD) and reflects the degree of inflammation. A good correlation between pouchitis activity (using the Pouchitis Disease Activity Index) and the MRP-14, interleukin-8, macrophage inflammatory protein-2alpha and matrix metalloproteinase-1 transcripts was observed.

INTERPRETATIONS AND CONCLUSIONS

Our data support the view that pouchitis reflects an inflammatory process that is different from that of underlying inflammatory bowel diseases, as the cytokine and chemokine patterns in pouchitis are neither typical of CD nor of UC, but maybe due to bacterial intestinal microflora overgrowth in the pouch lumen. Quantification of transcript levels allows an estimation of the extent of mucosal inflammation and may become helpful in the evaluation of the disease, especially in clinical trials.

Evidence for genetic variation as a factor in maintaining health

For many chronic diseases, the influence of genetics is subtle and complex and does not conform to simple Mendelian patterns of inheritance as is seen with single-gene disorders. Genetic variation can influence the propensity for the initiating event, the progression to a clinical disease state, and the trajectory of disease. One example of how genetic variations may affect complex diseases is provided by the interleukin 1 family of cytokines. This cytokine family plays a key role in mediating inflammation, which is a central component of many chronic diseases, including coronary artery disease and rheumatoid arthritis. Recent research has identified many sequence variations in the regulatory DNA of the genes coding for important members of the interleukin 1 family, and these variations are associated with differential effects on the inflammatory response. These in turn alter the risk of some diseases in which inflammation plays a role and also affect physiologic responses, such as the inflammatory response to exercise. As this new genetic knowledge is developed and extended, it may be possible to make health care interventions at an earlier stage, before clinical disease is established, rather than after tissues have been permanently damaged.