Frank Autschbach

High-Mobility Group Box-1 in Ischemia-Reperfusion Injury of the Heart

Background— High-mobility group box-1 (HMGB1) is a nuclear factor released by necrotic cells and by activated immune cells. HMGB1 signals via members of the toll-like receptor family and the receptor for advanced glycation end products (RAGE). Although HMGB1 has been implicated in ischemia/reperfusion (I/R) injury of the liver and lung, its role in I/R injury of the heart remains unclear. Methods and Results— Here, we demonstrate that HMGB1 acts as an early mediator of inflammation and organ damage in I/R injury of the heart. HMGB1 levels were already elevated 30 minutes after hypoxia in vitro and in ischemic injury of the heart in vivo. Treatment of mice with recombinant HMGB1 worsened I/R injury, whereas treatment with HMGB1 box A significantly reduced infarct size and markers of tissue damage. In addition, HMGB1 inhibition with recombinant HMGB1 box A suggested an involvement of the mitogen-activated protein kinases jun N-terminal kinase and extracellular signal-regulated kinase 1/2, as well as the nuclear transcription factor nuclear factor-&kgr;B in I/R injury. Interestingly, infarct size and markers of tissue damage were not affected by administration of recombinant HMGB1 or HMGB1 antagonists in RAGE−/− mice, which demonstrated significantly reduced damage in reperfused hearts compared with wild-type mice. Coincubation studies using recombinant HMGB1 in vitro induced an inflammatory response in isolated macrophages from wild-type mice but not in macrophages from RAGE−/− mice. Conclusions— HMGB1 plays a major role in the early event of I/R injury by binding to RAGE, resulting in the activation of proinflammatory pathways and enhanced myocardial injury. Therefore, blockage of HMGB1 might represent a novel therapeutic strategy in I/R injury.

Risk factors for ileoanal J pouch-related septic complications in ulcerative colitis and familial adenomatous polyposis

ObjectiveTo analyze the association between pre- and perioperative factors and pouch-related septic complications (PRSC) in ulcerative colitis (UC) and in familial adenomatous polyposis (FAP) after ileal pouch–anal anastomosis (IPAA). Summary Background DataFor patients with UC and FAP, IPAA is the surgical therapy of choice, but in some patients the outcome is compromised by PRSC. MethodsA total of 706 consecutive patients (494 UC, 212 FAP) were assessed in a study aimed at identifying subgroups of patients who were at high risk for PRSC. The rate of PRSC was analyzed as a time-dependent function (Kaplan-Meier estimation). Patients with UC and FAP were stratified separately according to associated factors (age, sex, surgeon’s experience, temporary ileostomy, colectomy before IPAA, anastomotic tension, and several factors specific for UC). ResultsIn all, 131 (19.2%) patients had PRSC (23.4% UC, 9.4% FAP). In patients with UC, the estimated 1-year PRSC rate was 15.6% and the estimated 3-year PRSC rate was 24.2%. In patients with FAP, the estimated 1-year and 3-year PRSC rates were 9.2%. The difference between the estimated rates of PRSC was significant (P < .001). In the univariate analysis, patients with UC younger than 50 years, with severe proctitis, with preoperative hemoglobin levels less than 10 g/L, or receiving corticoid medication had a significantly higher risk for PRSC (P = .039, P = .037, P = .047, P = .003, respectively). Multivariate analysis showed that patients with UC receiving a systemic prednisolone-equivalent corticoid medication of more than 40 mg/day had a significantly greater risk of developing pouch-related complications than patients with UC receiving 1 to 40 mg/day and patients with UC who were not receiving corticoid medication (RR: 3.78, 2.25, 1, respectively, P < .001). Patients with FAP proved to have a significantly higher risk for PRSC in the univariate and multivariate analyses if anastomotic tension had occurred (RR 3.60, P = .0086). ConclusionsPouch-related septic complications occur as late complications and should therefore be considered in regular, specific long-term follow-up examinations. The authors identified significant risk factors for PRSC specific to patients with UC and FAP; these must be considered for each individual surgical strategy.

Inhibition of Heme Oxygenase-1 Increases Responsiveness of Pancreatic Cancer Cells to Anticancer Treatment

Heme oxygenase-1 (HO-1) is believed to represent a key enzyme for the protection of cells against “stress.” Its overexpression in different types of human cancers supports the notion that HO-1 provides a growth advantage and contributes to cellular resistance against chemotherapy and radiotherapy. Given the poor survival rates of patients with pancreatic cancer due to its aggressive growth behavior and its exceptional resistance to all known forms of anticancer treatment, we have investigated the expression of HO-1 in human pancreatic cancer cells growth behavior and prognosis. Expression of HO-1 was analyzed in human pancreatic cancer samples in comparison with normal pancreas by quantitative PCR, Western blot, and confocal microscopy. The influence of radiotherapy and chemotherapy on HO-1 expression in pancreatic cancer cell lines was evaluated. Furthermore, HO-1 expression was specifically suppressed by small interfering RNA transfection and subsequently the alterations of growth behavior and resistance to anticancer treatment were tested. Human pancreatic cancer showed a 6-fold and 3.5-fold HO-1 up-regulation in comparison to normal pancreas based on mRNA and protein level, respectively (P < 0.05). Cancer tissues revealed marked HO-1 immunoreactivity in tumor cells and in tumor associated immunocytes. Treatment of the pancreatic cancer cell lines with gemcitabine or radiation strongly induced HO-1 expression. Targeted knockdown of HO-1 expression led to pronounced growth inhibition of the pancreatic cancer cells and made tumor cells significantly more sensitive to radiotherapy and chemotherapy. Therefore, specific inhibition of HO-1 expression may be a new option in pancreatic cancer therapy and may be used as sensitizer to chemotherapy and radiotherapy.

High prevalence of Mycobacterium avium subspecies paratuberculosis IS900 DNA in gut tissues from individuals with Crohn’s disease

Background and aims: Conflicting results exist about the presence of Mycobacterium avium subspecies paratuberculosis (MAP) specific IS900 DNA in Crohn’s disease (CD) tissues. Therefore, we examined IS900 in a large number of gut samples from patients with CD (n = 100) and ulcerative colitis (UC, n = 100), and in non-inflamed control tissues (nIBD, n = 100). We hypothesised that IS900 DNA detection might be associated with distinct clinical phenotypic characteristics in CD. Methods: The prevalence of MAP DNA in surgically resected tissues was examined using a mechanical-enzymatic disruption technique and nested IS900 specific polymerase chain reaction (PCR). CD patients were stratified according to the criteria of the Vienna classification and other clinical characteristics. Results: IS900 PCR detection rate was significantly higher in CD tissue samples (52%) than in UC (2%) or nIBD (5%) specimens (p<0.0001). In CD patients, IS900 DNA was detected in samples from both diseased small bowel (47%) as well as from the colon (61%). No firm association between MAP specific IS900 detection rates and clinical phenotypic characteristics in CD could be established. However, corticosteroid medication constituted a factor which tended to have a negative influence on IS900 DNA detection rates in CD (p<0.01). Conclusions: The presence of MAP specific IS900 DNA is a predominant feature of CD. Therapeutic intervention against MAP might represent a potential target for disease mitigation in Crohn’s disease.

In Situ Expression of Interleukin-10 in Noninflamed Human Gut and in Inflammatory Bowel Disease

A dysregulated secretion of contra-inflammatory cytokines such as interleukin-10 (IL-10) could play a role in the pathogenesis of inflammatory bowel disease (IBD). We have investigated the expression of IL-10 in gut tissues from patients with Crohns disease (CD), ulcerative colitis (UC) and controls by mRNA in situ hybridization and immunohistochemistry. Intestinal epithelial cells were found to express IL-10 mRNA and IL-10 protein in all of the tissues investigated without any major differences in the expression patterns. However, compared with noninflamed gut, significantly increased numbers of mononuclear cells (MNCs) producing IL-10 were present in inflamed gut, both in CD and UC. This cytokine was expressed most prominently by inflammatory infiltrates enriched in macrophages, although T cells seem to contribute to its production as well. Elevated IL-10 expression in IBD was mainly detected in the submucosa, whereas IL-10 production by lamina propria cells remained comparably low. In contrast, the expression of IL-1beta mRNA was preferentially increased in the lamina propria. Our data argue against a general deficiency in IL-10 production in IBD. The results suggest rather that the local production of IL-10 by mucosal MNCs in IBD is insufficient to down-regulate pro-inflammatory cytokines such as IL-1beta in the lamina propria compartment.

Updated German Guideline on Diagnosis and Treatment of Ulcerative Colitis, 2011

! Hintergrund Die Colitis ulcerosa (CU) ist neben dem Morbus Crohn die wichtigste chronisch-entzundliche Darmerkrankung (CED). Die Inzidenz fur die Colitis ulcerosa liegt in Deutschland bei bei 3,0–3,9 pro 100000 Einwohner [1, 2]. Die Pravalenz durfte in der westlichen Welt derzeit bei 160– 250 pro 100000 Einwohner liegen [3, 4]. Der hochste Gipfel der alterspezifischen Inzidenz liegt bei den 16bis 25-Jahrigen, wenn auch die Verteilung uber die Altersdekaden weit gleichmasiger ist als fruher beschrieben wurde [2]. Somit beginnt fur die meisten Patienten ihre Erkrankung wahrend der Schulzeit oder der Berufausbildung und dauert wahrend ihres gesamten beruflichen Lebens an. Daraus folgt, dass durch die Erkrankung nicht nur direkte Kosten (Medikamente, Arztbesuche, Operationen, Krankenhausaufenthalte etc.), sondern auch umfangreiche indirekte Kosten (Rente, Arbeitsausfalle etc.) entstehen. Es ist davon auszugehen, dass bei Patienten mit CU ca. die Halfte der Gesamtkosten den indirekten Kosten zuzuordnen sind [5]. An direkten medizinischen Kosten wurden dabei zuletzt zwischen 2500 und 5000€ pro Inhaltsverzeichnis! Hintergrund Die Colitis ulcerosa (CU) ist neben dem Morbus Crohn die wichtigste chronisch-entzündliche Darmerkrankung (CED). Die Inzidenz für die Colitis ulcerosa liegt in Deutschland bei bei 3,0–3,9 pro 100000 Einwohner [1, 2]. Die Prävalenz dürfte in der westlichen Welt derzeit bei 160– 250 pro 100000 Einwohner liegen [3, 4]. Der höchste Gipfel der alterspezifischen Inzidenz liegt bei den 16bis 25-Jährigen, wenn auch die Verteilung über die Altersdekaden weit gleichmäßiger ist als früher beschrieben wurde [2]. Somit beginnt für die meisten Patienten ihre Erkrankung während der Schulzeit oder der Berufausbildung und dauert während ihres gesamten beruflichen Lebens an. Daraus folgt, dass durch die Erkrankung nicht nur direkte Kosten (Medikamente, Arztbesuche, Operationen, Krankenhausaufenthalte etc.), sondern auch umfangreiche indirekte Kosten (Rente, Arbeitsausfälle etc.) entstehen. Es ist davon auszugehen, dass bei Patienten mit CU ca. die Hälfte der Gesamtkosten den indirekten Kosten zuzuordnen sind [5]. An direkten medizinischen Kosten wurden dabei zuletzt zwischen 2500 und 5000€ pro Inhaltsverzeichnis

Retarded release phosphatidylcholine benefits patients with chronic active ulcerative colitis

Background and aims: We examined the hypothesis of an anti-inflammatory effect of phosphatidylcholine in ulcerative colitis. Methods: A phase IIA, double blind, randomised, placebo controlled study was performed in 60 patients with chronic active, non steroid dependent, ulcerative colitis, with a clinical activity index (CAI) of ⩾4. Retarded release phosphatidylcholine rich phospholipids and placebo were administered at a dose of 6 g daily over three months. The primary end point was a change in CAI towards clinical remission (CAI ⩽3) or CAI improvement by ⩾50%. Secondary end points included ⩾50% changes in endoscopic activity index (EAI), histology, and quality of life scores. Results: Induction of clinical remission (CAI ⩽3) as the primary outcome variable was attained by 16 (53%) patients in the phosphatidylcholine treated group compared with three (10%) in the placebo group (p<0.00001). The rate of clinical remission and CAI improvement was 90% in the phosphatidylcholine group and only 10% in the placebo group. A median drop of seven points in the CAI score (70% improvement) was recorded in the phosphatidylcholine group compared with no change in the placebo group. Secondary end point analysis revealed concomitant drops in EAI and histology scores (p = 0.00016 and p = 0.0067 compared with placebo, respectively). Improvement in quality of life was reported by 16 of 29 evaluated patients in the phosphatidylcholine group compared with two of 30 in the placebo group (p = 0.00005). Conclusion: Retarded release oral phosphatidylcholine is effective in alleviating inflammatory activity caused by ulcerative colitis.

Regulation of DMBT1 via NOD2 and TLR4 in Intestinal Epithelial Cells Modulates Bacterial Recognition and Invasion

Mucosal epithelial cell layers are constantly exposed to a complex resident microflora. Deleted in malignant brain tumors 1 (DMBT1) belongs to the group of secreted scavenger receptor cysteine-rich proteins and is considered to be involved in host defense by pathogen binding. This report describes the regulation and function of DMBT1 in intestinal epithelial cells, which form the primary immunological barrier for invading pathogens. We report that intestinal epithelial cells up-regulate DMBT1 upon proinflammatory stimuli (e.g., TNF-α, LPS). We demonstrate that DMBT1 is a target gene for the intracellular pathogen receptor NOD2 via NF-κB activation. DMBT1 is strongly up-regulated in the inflamed intestinal mucosa of Crohn’s disease patients with wild-type, but not with mutant NOD2. We show that DMBT1 inhibits cytoinvasion of Salmonella enterica and LPS- and muramyl dipeptide-induced NF-κB activation and cytokine secretion in vitro. Thus, DMBT1 may play an important role in the first line of mucosal defense conferring immune exclusion of bacterial cell wall components. Dysregulated intestinal DMBT1 expression due to mutations in the NOD2/CARD15 gene may be part of the complex pathophysiology of barrier dysfunction in Crohn’s disease.

T cells of the human intestinal lamina propria are high producers of interleukin-10

Background and aim —Some of the recently observed functional features characteristic of immunocompetent cells residing in the human intestinal lamina propria could be mediated by interleukin- 10 (IL-10). To investigate the role of IL-10 in the human intestinal mucosa, the regulation of IL-10 production by lamina propria T lymphocytes (LPL-T) was determined and compared with that of peripheral blood T lymphocytes (PBL-T). Methods —Following activation by using different stimuli, IL-10 release by LPL-T and PBL-T into the supernatant was measured by enzyme linked immunosorbent assay (ELISA). In parallel, cell growth was determined by [3H]-thymidine incorporation. Results —Neither LPL-T nor PBL-T release IL-10 constitutively. Triggering through CD2 or the T cell receptor (TCR)/CD3 complex in the presence of autologous monocytes induces significantly greater IL-10 secretion by LPL-T than by PBL-T. Engagement of the CD45 receptor enhances IL-10 release and proliferation of CD2 triggered CD45RO+ PBL-T. In contrast, it reduces CD2 induced IL-10 production by LPL-T without altering cell growth significantly . Conclusions—Activated LPL-T release relatively high amounts of IL-10. Enhanced IL-10 production by activated LPL-T, in comparison with activated PBL-T, is not only related to the presence of a higher proportion of CD45RO+ T cells in the intestinal lamina propria, but is also caused by increased sensitivity of LPL-T to CD2 co-stimulation. The differential responsiveness of LPL-T, compared with PBL-T, to CD45 engagement demonstrates that CD45 could be involved in the altered CD2 reactivity of LPL-T.

Cytokine/chemokine messenger-RNA expression profiles in ulcerative colitis and Crohn's disease

Abstract Abstract. To define mediator profiles in inflamed and noninflamed areas in inflammatory bowel disease (IBD) we analyzed the expression of 35 messenger-RNAs (mRNAs) encoding cytokines, chemokines, and some related molecules in transmural gut tissues (n=138) from patients with ulcerative colitis (UC), Crohns disease (CD), and inflammatory and normal controls by real-time quantitative reverse transcription polymerase chain reaction. Using sample collectives with a comparable degree of inflammation, most parameters investigated showed similarly increased mRNA expression levels in both active UC and CD. This included proinflammatory cytokines, but also interferon (IFN) γ and several IFN-γ inducible chemokines. Only macrophage inflammatory protein (MIP)-2α mRNA was expressed at higher levels in inflamed UC vs. CD. IH revealed that MIP-2α protein was produced mainly by intestinal epithelial cells. Importantly, in histologically noninflamed/inactive IBD samples mRNAs for several mediators were significantly enhanced, accompanied by elevated levels of migration-inhibition factor related protein (MRP) 14 transcripts. CD14 positive macrophages were found especially in noninflamed/inactive UC, many of which coexpressed the RFD-7 antigen. Our results indicate a substantial overlap in cytokine/chemokine mRNA expression in UC and CD. Elevated mediator expression is evident in noninflamed/inactive areas in both diseases. Local recruitment of MRP-14 positive leukocytes might contribute to this phenomenon. In inactive UC a phenotypically altered population of macrophages expressing CD14 might play an additional role.