Effect of magnesium supplementation and depletion on the onset and course of acute experimental pancreatitis.

BACKGROUND AND OBJECTIVE: High calcium concentrations are an established risk factor for pancreatitis. We have investigated whether increasing magnesium concentrations affect pathological calcium signals and premature protease activation in pancreatic acini, and whether dietary or intraperitoneal magnesium administration affects the onset and course of experimental pancreatitis. METHODS: Pancreatic acini were incubated with up to 10 mM magnesium; [Ca(2+)](i) (fura-2AM) and intracellular protease activation (fluorogenic substrates) were determined over 60 min. Wistar rats received chow either supplemented or depleted for magnesium (<300 ppm to 30 000 ppm) over two weeks before pancreatitis induction (intravenous caerulein 10 µg/kg/h/4 h); controls received 1 µg/kg/h caerulein or saline. C57BL6/J mice received four intraperitoneal doses of magnesium (NaCl, Mg(2+) 55 192 or 384 mg/kg bodyweight) over 72 h, then pancreatitis was induced by up to eight hourly supramaximal caerulein applications. Pancreatic enzyme activities, protease activation, morphological changes and the immune response were investigated. RESULTS: Increasing extracellular Mg(2+) concentration significantly reduced [Ca(2+)](i) peaks and frequency of [Ca(2+)](i) oscillations as well as intracellular trypsin and elastase activity. Magnesium administration reduced pancreatic enzyme activities, oedema, tissue necrosis and inflammation and somewhat increased Foxp3-positiv T-cells during experimental pancreatitis. Protease activation was found in animals fed magnesium-deficient chow-even with low caerulein concentrations that normally cause no damage. CONCLUSIONS: Magnesium supplementation significantly reduces premature protease activation and the severity of pancreatitis, and antagonises pathological [Ca(2+)](i) signals. Nutritional magnesium deficiency increases the susceptibility of the pancreas towards pathological stimuli. These data have prompted two clinical trials on the use of magnesium in patients at risk for pancreatitis.

Single-balloon enteroscopy-assisted endoscopic retrograde cholangiopancreaticography in patients with surgically altered anatomy: higher failure rate in malignant biliary obstruction - a prospective single center cohort analysis.

INTRODUCTION: The performance of endoscopic retrograde cholangiopancreaticography (ERCP) in patients with post-surgically altered anatomy is technically ambitious. Our study aimed at comparing a cohort of patients having successfully undergone single-balloon enteroscopy (SBE)-assisted ERCP to those in whom SBE-ERCP failed. METHODS: This trial is a prospective single center cohort study. Participants included 30 patients (median age 69.5 years, range 20-86 years) with previous pancreaticobiliary surgery. First, a conventional ERCP approach was attempted in all patients. Additionally, those patients in whom prior conventional ERCP had failed underwent SBE-ERCP (n = 26). Patients' baseline characteristics were retrieved and patient cohorts with and without successful SBE-ERCPs were compared and analyzed. Statistical analysis was applied. Univariate analysis was performed to detect possible risk factors of SBE-ERCP failure. RESULTS: The overall success rate of SBE-ERCP, including two patients with percutaneous transhepatic cholangiography- assisted rendezvous technique was 65.4% (17/26). Patients with malignant obstructive cholestasis had a significantly higher failure rate compared to those with benign strictures (84.2% vs. 14.2%, p < 0.001). DISCUSSION: SBE-ERCP is a promising tool for diagnostic and therapeutic procedures in the pancreaticobiliary system of selected, previously operated patients with failure of conventional ERCP. However, higher failure rates in malignant biliary obstruction should be taken into account.

Clearance of refractory bile duct stones with Extracorporeal Shockwave Lithotripsy: higher failure rate in obese patients.

OBJECTIVE: Bile duct stones that cannot be removed endoscopically are still a challenge in interventional gastroenterology. Extracorporeal shockwave lithotripsy (ESWL) with subsequent endoscopic extraction of residual fragments is an established treatment option if other endoscopic means are not successful. Our study aimed to investigate the efficacy and safety of ESWL for clearance of refractory bile duct stones. MATERIAL AND METHODS: A total of 73 consecutive patients treated for refractory choledocholithiasis with ESWL were retrospectively analyzed. Success and complication rates were calculated. RESULTS: Complete stone clearance was achieved in 66 cases (90%). Patients with complete clearance had a significantly lower body mass index or BMI (25.55 ± 5.01 kg/m² vs. 31.60 ± 6.26 kg/m², p = 0.035) and needed less ESWL treatments (3.61 ± 1.87 vs. 5.00 ± 1.63, p = 0.048). A relevant drop of hemoglobin occurred significantly more often in the group with partial clearance (43% vs. 6%, p = 0.005). CONCLUSIONS: ESWL proves to be an excellent clearing approach to refractory bile duct stones with high success rates. However, obesity is one risk factor for ESWL failure and higher procedural hazard.

Miniprobe endoscopic ultrasound accurately stages esophageal cancer and guides therapeutic decisions in the era of neoadjuvant therapy: results of a multicenter cohort analysis.

BACKGROUND: Despite recent advances in imaging techniques, adequate classification of esophageal lesions is still challenging. Accurate staging of tumors of the esophagus is a precondition for targeted therapy. In this retrospective, multicenter study, we report the role of high-frequency endoscopic ultrasound (EUS) catheter probes in pretherapeutic staging of esophageal neoplasms and thus guiding treatment decisions. METHODS: A total of 143 patients (mean age of 63.8 ± 10.7 years) with esophageal carcinoma were recruited from five German centers (Münster, Oldenburg, Hannover, Wiesbaden, and Lüneburg). Tumor type was adenocarcinoma in 112 (78 %) cases and squamous cell carcinoma in 31 (22 %). Tumor localization was as follows: proximal 3, mid esophagus 7, and distal third 133. Histological correlation either through EMR or surgery was available. In all patients, pretherapeutic uT and uN classifications were compared to pT/pN classification obtained from surgically (esophagectomy, n = 93) or endoscopically (EMR, n = 50) resected tissue. RESULTS: Overall, accuracy of uT classification was 60 % and of uN classification was 74 %. Sensitivity, specificity, and accuracy rates for local tumor extension were as follows (%): T1: 68/97/83; T2: 39/84/75; T3: 72/81/79; T4: 13/97/93; T1/2: 73/81/75; T3/4: 78/82/81. Relating to positive lymph node detection, sensitivity and specificity were 76 and 71 %, respectively. CONCLUSIONS: Miniprobe EUS is an established method for the staging of esophageal tumors. Our large multicenter cohort shows a solid accuracy of miniprobe EUS with respect to differentiating locally advanced from limited cancer and assisting to determine the treatment regimen in the era of neoadjuvant therapy; consequently, 78 % of patients would have been assigned to the adequate therapeutic regimen, whereas 11 % of patients would have been overtreated and 11 % undertreated.

Endoscopic transpapillary biopsies are of limited value in the diagnostics of bile duct strictures of unknown etiology-results of a histopathologically controlled study in 312 patients.

BACKGROUND/AIMS: Our investigation aimed to evaluate the impact of endoscopic transpapillary forceps biopsies (ETP) in bile duct strictures of unknown etiology based on the largest European patient cohort at a tertiary referral center. To date only studies with limited patient numbers exist. METHODOLOGY: Three-hundred-and-twelve patients (162 males, 150 females, mean age 62±12.7 years) with bile duct strictures of unknown etiology were examined with ETP. Sensitivity, specificity and accuracy of ETP were compared to the definite diagnosis proved by histopathology of surgical resection specimens or long-term follow-up of those patients not undergoing surgery. RESULTS: Using ETP a correct pe-interventional diagnosis was achieved in 211 out of 312 patients resulting in an accuracy rate of 67.6%. Eighty-six out of 187 malignant stenoses were correctly diagnosed by ETP, giving rise to sensitivity and specificity rates of 46 and 100%, respectively. Sensitivity of ETP in cholangiocellular carcinoma was significantly superior to that in pancreatic carcinoma (52.5% vs. 35.6%, p = 0.026). Sensitivity and accuracy rates of ETP did not depend on the localization of the stenosis in the common bile duct. CONCLUSIONS: ETP alone is not reliable enough in diagnosing bile duct malignancies as shown by low sensitivity and accuracy rates (false-negative rate of 32%).

The tripeptide KdPT protects from intestinal inflammation and maintains intestinal barrier function.

Treatment options for inflammatory bowel disease (IBD) are incompletely helpful, and surgery is often needed. One promising class of future therapeutic agents for IBD is melanocortin-related peptides, which exhibit potent immunomodulatory effects. We investigated KdPT, a tripeptide derivative of the C-terminus of α-melanocyte-stimulating hormone, as an anti-inflammatory small molecule in vivo and in vitro. Intestinal inflammation was studied after oral administration of dextran sodium sulfate and in IL-10 gene-deficient mice. The effects of KdPT on key colonic epithelial cell functions were studied in vitro and in vivo by evaluating proliferation, wound healing, transepithelial resistance, and expression of tight junction proteins. Melanin assays were performed to determine the melanotropic effects of KdPT. KdPT-treated animals showed markedly reduced severity of inflammation in both colitis models. In colonic epithelial cells, KdPT increased proliferation, accelerated closure of wounds, and improved transepithelial electrical resistance after stimulation with interferon-γ/tumor necrosis factor-α. Moreover, treatment with KdPT also prevented the loss of tight junction protein expression and improved barrier function in vivo. KdPT acted independently of IL-1 receptor type I in vivo and did not affect melanogenesis in vitro. KdPT is capable of attenuating the course of experimental colitis in different models and maintains epithelial cell function. Furthermore, KdPT does not induce pigmentation, emphasizing the potential of this small molecule for the future treatment of IBD.

Feasibility of snare papillectomy in ampulla of Vater tumors: meta-analysis and study results from a tertiary referral center.

BACKGROUND/AIMS: Ampulla of Vater tumors represent a rare tumor entity and bear a malignant potential. This study at our tertiary referral center aimed at evaluating the feasibility of endoscopic snare papillectomy and long-term endoscopic surveillance in comparison to results of a meta-analysis of comparative trials. METHODOLOGY: Retrospective study in comparison to results of a meta-analysis. Twenty-one patients (mean age 60.2±12.8 years) with ampullary adenoma were included. All patients had undergone ERCP with endoscopic forceps biopsies prior to endoscopic snare papillectomy. Statistical analysis was applied including descriptive analysis of symptoms, therapy and complications. RESULTS: ESP was technically successful in all 21 patients. Histopathology showed 18 adenomas and 3 focal adenocarcinomas which were referred to surgery for modified Whipple's procedure. Follow-up was available in all patients with a mean follow-up of 64 months. Adenoma recurrence occurred in three patients with a mean recurrence time of 25 months (range, 4-66 months). One patient had residual adenoma growth. CONCLUSIONS: In the majority of cases ampullary adenomas can be treated endoscopically. Forceps biopsies alone are not reliable enough in detecting malignancy. All patients with ampullary tumor should therefore undergo ESP. Due to the recurrence rate of 16% patients should have close follow-up.

Enoxaparin improves the course of dextran sodium sulfate-induced colitis in syndecan-1-deficient mice.

Syndecan-1 (Sdc1) plays a major role in wound healing and modulates inflammatory responses. Sdc1 expression is reduced in lesions of patients with ulcerative colitis. The aim of this study was to investigate the role of Sdc1 in murine dextran sodium sulfate (DSS)-induced colitis. DSS colitis was induced in Sdc1-deficient (knockout (KO)) and wild-type mice by oral administration of 3% DSS. KO mice exhibited a significantly increased lethality as compared with wild-type controls (61 versus 5%, P < 0.05). Impaired mucosal healing and prolonged recruitment of inflammatory cells in KO mice were accompanied by significant up-regulation of tumor necrosis factor-alpha, CC chemokine ligand 3/macrophage inflammatory protein-1alpha, and vascular cell adhesion molecule-1, as determined by histological correlation between 0 and 15 days after colitis induction, TaqMan low-density array analysis, and quantitative real-time PCR. Treatment from days 7 through 14 with enoxaparin, a functional analogue of the Sdc1 heparan sulfate chains, significantly reduced lethality of KO mice due to DSS-induced colitis, which was correlated with improved mucosal healing. In vitro, Sdc1-deficient polymorphonuclear cells displayed increased adhesion to endothelial cells and intercellular adhesion molecule-1, and enoxaparin reverted adhesion to wild-type levels. Small interfering RNA-mediated knockdown of Sdc1 expression resulted in reduced basic fibroblast growth factor-mediated mitogen-activated protein kinase signaling and reduced Caco-2 cell proliferation. We conclude that Sdc1 has a protective effect during experimental colitis. The modification of missing Sdc1 function by heparin analogues may emerge as a promising anti-inflammatory approach.

Single-step versus multi-step transmural drainage of pancreatic pseudocysts: the use of cystostome is effective and timesaving.

BACKGROUND AND AIMS: Pancreatic pseudocysts are a major complication of chronic and acute pancreatitis and often require endoscopic intervention. Endoscopic single-step and multi-step transmural drainage techniques have been reported in the literature. The aim of this study was to evaluate and compare technical results and clinical outcome rates of the single-step versus multi-step endoscopic ultrasonography (EUS)-guided endoscopic transmural drainage in patients with symptomatic pancreatic pseudocysts of >4 cm size. DESIGN: Retrospective study at an academic tertiary referral center. PATIENTS AND METHODS: A total of 38 consecutive patients comprising 42 interventions were studied: 16 patients with pancreatic pseudocysts (18 interventions) had undergone single-step EUS-guided transmural cystostome drainage between 2007 and 2010. Results were compared with a cohort of 22 patients who had submitted to multi-step EUS-guided transmural drainage of pancreatic pseudocysts in 24 cases between 2005 and 2007. RESULTS: The technical success rate for using the single-step procedure was 94% compared with multi-step procedure with 83% (n.s.). Primary clinical success rate was 88% for single-step drainage and 90% for the multi-step approach (n.s.). The mean procedure time was 36 ± 9 min in the single-step group compared with 62 ± 12 min for the multi-step access (p < 0.001). CONCLUSIONS: The use of single-step cystostome appears useful in managing selected patients with symptomatic pancreatic pseudocysts as it is effective and timesaving.

Outcome of supraselective transarterial chemoembolization in patients with hepatocellular carcinoma.

OBJECTIVE: Hepatocellular carcinoma (HCC) is the most common tumor in cirrhotic patients with a median survival of only 8-10 months if untreated. Supraselective transarterial chemoembolization (STACE) is supposed to be a well-established method for treating HCC patients. In the present study, we evaluated the effect of STACE on post-transplant survival in patients with HCC. MATERIAL AND METHODS: The charts of 53 HCC patients were retrospectively analyzed. Twenty-seven patients had STACE as a bridging therapy while 26 patients were scheduled for liver transplantation (LTX) without prior STACE therapy. A total of 53% of the patients who underwent LTX preoperatively fulfilled the Milan criteria, while 70.6% fulfilled the expanded University of California, San Francisco (UCSF) transplant criteria. Primary endpoint was the post-transplant survival. Statistical analysis included Kaplan-Meier-method, log rank, and chi square tests. RESULTS: Between the LTX groups (STACE vs. non-STACE), there was no significant difference in terms of age, Child classification, Okuda stage, co-morbidities, underlying disease, and post-transplant survival (p > 0.05). Independent of prior STACE, however, disease-free survival after LTX was highly significantly prolonged if LTX was performed within 3 months after initial diagnosis of HCC (p < 0.01) or if patients met the expanded transplant UCSF criteria (p = 0.02). Post-transplant survival did not depend on tumor size. CONCLUSIONS: We conclude that STACE performed prior to LTX does not secure any post-transplant survival benefit, while early LTX, i.e. within 3 months after HCC diagnosis, does improve survival regardless of whether STACE was performed or not. Additionally, fulfillment of the expanded transplant UCSF criteria leads to a prolonged post-transplant survival.

Long-term efficacy and safety of double balloon enteroscopy--prospective and retrospective data from a single center study.

OBJECTIVE: Double balloon enteroscopy (DBE) has evolved as one of the most innovative and fast spreading endoscopic procedures in the last decade. With increasing experience of performing endoscopic procedures in the mid gut outside the operating room it is necessary to investigate the effectiveness of DBE regarding therapeutic consequences, long-term efficacy as well as safety. MATERIAL AND METHODS: To address this we retrospectively analyzed all DBE performed over a period of 2 years at our department. Furthermore, in order to evaluate long-term effectiveness of DBE procedures we performed a follow-up analysis on all patients, whose DBE procedure was at least 6 months ago. In addition, 100 consecutive patients who underwent DBE were questioned regarding procedure associated complaints using a standardized questionnaire. RESULTS: Retrospective analysis of all DBE procedures performed in our department before November 2006 (n = 545) revealed an overall diagnostic yield of 39.7% and a therapeutic yield of 31.1%. The overall number of major complications accounted to 0.9%. Follow-up analysis revealed a long-term effect of endoscopic interventions in more than 50%, while in those patients with an initially negative DBE long-term follow-up only revealed symptom explaining findings in 17% with the majority of the other patients being asymptomatic during follow-up. Regarding patient related complaints the prospective analysis showed that DBE procedures in general are well tolerated with the most common complaint being meteorism. CONCLUSIONS: DBE showed to be a relatively safe and well tolerated procedure. However, more sensitive algorithms are needed to enhance the therapeutic results.

The role of kinesin, dynein and microtubules in pancreatic secretion.

The regulated secretion of pancreatic zymogens depends on a functional cytoskeleton and intracellular vesicle transport. To study the dynamics of tubulin and its motor proteins dynein and kinesin during secretion in pancreatic acinar cells, we infused rats with 0.1 mug/kg/h caerulein. Electron and fluorescence microscopy detected neither dynein nor kinesin at the apical secretory pole, nor on the surface of mature zymogen granules. After 30 min of secretagogue stimulation, kinesin and the Golgi marker protein 58 K were reallocated towards the apical plasma membrane and association of kinesin with tubulin was enhanced. Disruption of acinar cell microtubules had no effect on initial caerulein-induced amylase release but completely blocked secretion during a second stimulus. Our results suggest that mature zymogen granule exocytosis is independent of intact microtubules, kinesin and dynein. However, microtubule-dependent mechanisms seem to be important for the replenishment of secretory vesicles by redistribution of Golgi elements towards the apical cell pole.

Prevalence, associations, and trends of biliary-tract candidiasis: a prospective observational study.

BACKGROUND: Biliary obstruction and cholangitis are common problems in gastroenterology. Infections of the biliary tract with Candida and other fungal species have increasingly been seen in the last few years. OBJECTIVE: To investigate the prevalence, associations, and trends of biliary-tract candidiasis. DESIGN: A prospective, observational, diagnostic study. SETTING: University Hospital, Muenster, Germany. PATIENTS: Consecutive patients undergoing ERCP for various indications. RESULTS: In 54 of 123 patients, we found Candida species in bile samples (44%). In only 7 patients, candidiasis was suspected on endoscopy before mycologic proof. Only 4 of these 7 patients were correctly diagnosed with biliary candidiasis by simple morphologic aspects. The fungus was mainly differentiated as Candida albicans or Candida glabrata and rarely as Candida parapsilosis, Candida tropicalis, or other subspecies. Immunosuppression for various reasons was significantly associated with bile-duct candidiasis (P < .02). No significant association was found between positive fungal cultures and prior endoscopic sphincterotomy (P = .0824) or prior ERCP (P = .1152). Biliary candidiasis was neither associated with positive fungal cultures of buccal smears (P = .0722) nor with positive findings in stool samples (P = .0860). LIMITATIONS: Highly selected patient population. Buccal smears and stool samples were not obtained from all patients. Contamination artifacts cannot totally be excluded with the ERCP procedure. CONCLUSIONS: Candida species very frequently can be detected in the bile. Positive fungal cultures of bile samples are not just contamination artifacts. This has to be taken into account when designing an anti-infectious treatment for recurrent cholangitis or even more cholangiosepsis. Especially in immunosuppressed patients or recipients of long-term antibiotic therapy, physicians should screen for biliary-tract candidiasis during endoscopic examination.

The absence of cutaneous lymph nodes results in a Th2 response and increased susceptibility to Leishmania major infection in mice.

Lymph nodes (LNs) are important sentinel organs where antigen-presenting cells interact with T cells to induce adaptive immune responses. In cutaneous infection of mice with Leishmania major, resistance depends on the induction of a T-helper-cell-1 (Th1)-mediated cellular immune response in draining, peripheral LNs. We investigated whether draining, peripheral LNs are absolutely required for resistance against L. major infection. We investigated the course of experimental leishmaniasis in wild-type (wt) mice lacking peripheral LNs (pLNs), which we generated by in utero blockade of membrane-bound lymphotoxin, and in mice lacking pLNs or all LNs due to genetic deletion of lymphotoxin ligands or receptors. wt mice of the resistant C57BL/6 strain without local skin-draining LNs were still able to generate specific T-cell responses, but this yielded Th2 cells. This switch to a Th2 response resulted in severe systemic infection. We also confirmed these results with mice lacking pLNs due to genetic depletion of lymphotoxin-beta. The complete absence of LNs due to a genetic depletion of the lymphotoxin-beta receptor also resulted in a marked deterioration of disease and a Th2 response. Thus, in the absence of pLNs, an L. major-specific Th2 response is induced in the remaining secondary lymphoid organs, such as the spleen and non-skin-draining LNs. This indicates a critical requirement for pLNs to induce protective Th1 immunity and suggests that whether Th1 or Th2 priming to the same antigen occurs depends on the site of the primary antigen recognition.

The calcium binding protein S100A9 is essential for pancreatic leukocyte infiltration and induces disruption of cell-cell contacts.

Leukocyte infiltration is an early and critical event in the development of acute pancreatitis. However, the mechanism of leukocyte transmigration into the pancreas and the function of leukocytes in initiating acute pancreatitis are still poorly understood. Here, we studied the role of S100A9 (MRP14), a calcium binding protein specifically released by polymorph nuclear leukocytes (PMN), in the course of acute experimental pancreatitis. Acute pancreatitis was induced by repeated supramaximal caerulein injections in S100A9 deficient or S100A9 wild-type mice. We then determined S100A9 expression, trypsinogen activation peptide (TAP) levels, serum amylase and lipase activities, and tissue myeloperoxidase (MPO) activity. Cell-cell contact dissociation was analyzed in vitro with biovolume measurements of isolated acini after incubation with purified S100A8/A9 heterodimers, and in vivo as measurement of Evans Blue extravasation after intravenous application of S100A8/A9. Pancreatitis induced increased levels of S100A9 in the pancreas. However, infiltration of leukocytes and MPO activity in the lungs and pancreas during acute pancreatitis was decreased in S100A9-deficient mice and associated with significantly lower serum amylase and lipase activities as well as reduced intrapancreatic TAP-levels. Incubation of isolated pancreatic acini with purified S100A8/A9-heterodimers resulted in a rapid dissociation of acinar cell-cell contacts which was highly calcium-dependent. Consistent with these findings, in vivo application of S100A8/A9 in mice was in itself sufficient to induce pancreatic cell-cell contract dissociation as indicated by Evans Blue extravasation. These data show that the degree of intrapancreatic trypsinogen activation is influenced by the extent of leukocyte infiltration into the pancreas which, in turn, depends on the presence of S100A9 that is secreted from PMN. S100A9 directly affects leukocyte tissue invasion and mediates cell contact dissociation via its calcium binding properties.

Double balloon enteroscopy: a useful tool for diagnostic and therapeutic procedures in the pancreaticobiliary system.

OBJECTIVES: Diagnostic and therapeutic interventions in the biliary and pancreatic system in the previously operated patient by conventional endoscopic retrograde cholangiopancreaticography (ERCP) are difficult and, depending on the surgical procedure, in many cases unsuccessful. We describe our experience of ERCP performed with a double balloon enteroscope (DBE) as an alternative examination technique for these patients. METHODS: In a retrospective analysis of all DBE procedures at our department between November 2004 and June 2007, 11 patients were identified with various anatomic variations in whom ERCP was performed using a DBE. RESULTS: In 72% of the patients, previous conventional ERCP examinations failed (8/11). In these patients, DBE-ERCP was successful in 63%. The overall success rate of DBE-ERCP in all patients was 64% (7/11 patients). In those patients, interventions such as papillotomy, calculus extractions, as well as stent placement could be performed even though tools for DBE-ERCP are still very limited. Despite most of the DBE-ERCPs having included therapeutic interventions, no major complications occurred in our case series and minor side effects were restricted to meteorism and mild to moderate abdominal pain. CONCLUSIONS: DBE-ERCP is an alternative method for diagnostic as well as therapeutic interventions in the biliary as well pancreatic system in the operated patient. However, it should be limited to selected patients, e.g., with contraindications for PTC, as it is a time-consuming as well as a cost-intensive procedure.

Melanocortin-derived tripeptide KPV has anti-inflammatory potential in murine models of inflammatory bowel disease.

BACKGROUND: Despite some progress in recent years, the options for treating inflammatory bowel disease (IBD) are still dissatisfying, and surgery rates are still high. The anti-inflammatory effects of melanocortin peptides such as alpha-melanocyte-stimulating hormone (alpha-MSH) have been described recently in, for example, dextran sodium sulfate (DSS) colitis in mice. The aim of this study was to investigate the therapeutic potential of the melanocortin-derived tripeptide alpha-MSH(11-13) (KPV) and its mode of action in 2 models of intestinal inflammation. METHODS: The anti-inflammatory activity of KPV was analyzed in 2 well-described models of IBD: DSS colitis, and CD45RB(hi) transfer colitis. Furthermore, animals expressing a nonfunctional melanocortin-1 receptor (MC1Re/e) received DSS for induction of colitis and were treated with KPV. The course of inflammation was monitored by weight loss and histological changes in the colon as well as by myeloperoxidase (MPO) activity. RESULTS: In the DSS-colitis model, treatment with KPV led to earlier recovery and significantly stronger regain of body weight. Histologically, inflammatory infiltrates were significantly reduced in KPV-treated mice, which was confirmed by the significant reduction of MPO activity in colonic tissue after KPV treatment. Supporting these findings, KPV treatment of transfer colitis led to recovery, regain of body weight, and reduced inflammatory changes histologically. In MC1Re/e mice, KPV treatment rescued all animals in the treatment group from death during DSS colitis. CONCLUSIONS: The melanocortin-derived tripeptide KPV showed significant anti-inflammatory effects in 2 murine models of colitis. These effects seem to be at least partially independent of MC1R signaling. In conclusion, our data suggest KPV as an interesting therapeutic option for the treatment of IBD.

Macrophage migration inhibitory factor may contribute to vasculopathy in systemic sclerosis.

Increasing evidence supports the concept of macrophage migration inhibitory factor (MIF) as a central proinflammatory cytokine in autoimmune diseases. To further evaluate its role in systemic sclerosis (SSc), serum levels of MIF were determined by enzyme-linked immunoassay, and correlations to clinical manifestations were analyzed in 43 patients. MIF levels were significantly increased in patients (median, 18.8; range, <0.015-189 ng/ml) in comparison to healthy controls (n=43, 8.0, <0.015-36.5 ng/ml; P<0.0005). MIF values were higher in diffuse than in limited cutaneous SSc (P<0.005). Patients with pulmonary hypertension and recurrent digital ulcers showed higher MIF levels than patients without these manifestations (P<0.005). This association was also observed in limited cutaneous SSc. Sequential studies revealed decreased MIF levels after initiation of immunosuppressive therapy. MIF levels were not significantly different in patients with and without macrovascular disease of the peripheral arteries. The results suggest that MIF might contribute to inflammation and vasculopathy in SSc.