J. Lonovics

Fontolizumab, a humanised anti-interferon gamma antibody, demonstrates safety and clinical activity in patients with moderate to severe Crohn's disease.

Introduction: Interferon γ is a potent proinflammatory cytokine implicated in the inflammation of Crohn’s disease (CD). We evaluated the safety and efficacy of fontolizumab, a humanised anti-interferon γ antibody, in patients with moderate to severe CD. Methods: A total of 133 patients with Crohn’s disease activity index (CDAI) scores between 250 and 450, inclusive, were randomised to receive placebo or fontolizumab 4 or 10 mg/kg. Forty two patients received one dose and 91 patients received two doses on days 0 and 28. Investigators and patients were unaware of assignment. Study end points were safety, clinical response (decrease in CDAI of 100 points or more), and remission (CDAI ⩽150). Results: There was no statistically significant difference in the primary end point of the study (clinical response) between the fontolizumab and placebo groups after a single dose at day 28. However, patients receiving two doses of fontolizumab demonstrated doubling in response rate at day 56 compared with placebo: 32% (9/28) versus 69% (22/32, p = 0.02) and 67% (21/31, p = 0.03) for the placebo, and 4 and 10 mg/kg fontolizumab groups, respectively. Stratification according to elevated baseline C reactive protein levels resulted in a decreased placebo response and pronounced differences in clinical benefit. Two grade 3 adverse events were reported and were considered to be related to CD. One death (during sleep) and one serious adverse event (an elective hospitalisation) occurred, both considered unrelated. Conclusion: Treating active CD with fontolizumab was well tolerated and resulted in increased rates of clinical response and remission compared with placebo.

Involvement of oxygen-derived free radicals in L-arginine-induced acute pancreatitis

This study was aimed at an assessment of the role of oxygen-derived free radicals in the pathogenesis of L-arginine (Arg)-induced acute pancreatitis in rat, by measuring the levels of malonyl dialdehyde (MDA), glutathione peroxidase (GPx), catalase, and superoxide dismutase (Mn- and Cu,Zn-SOD) in the pancreatic tissue, and evaluating the protective effect of the xanthine oxidase inhibitor allopurinol. Acute pancreatitis was induced in male Wistar rats by injecting 2 × 250 mg/100 g body weight of Arg intraperitoneally in a 1-hr interval, as a 20% solution in 0.15 M NaCl. Control rats received the same quantity of glycine. Allopurinol, 100 or 200 mg/kg, was administered subcutaneously 30 min before the first Arg injection. Rats were killed at 6, 12, 24, and 48 hr following Arg administration, and acute pancreatitis was confirmed by a serum amylase level elevation and typical inflammatory features observed microscopically. The serum level of amylase reached the peak level at 24 hr after the Arg injection (30,800 ± 3813 vs 6382 ± 184 units/liter in the control) and normalized at 48 hr. The tissue concentration of MDA was significantly elevated at 24 hr and reached the peak value at 48 hr (5.00 ± 1.75 vs 0.28 ± 0.05 nM/mg protein in the control). The catalase and Mn-SOD activities were significantly decreased throughout the study, while the GPx activity was significantly reduced at 6 and 12 hr, and the Cu,Zn-SOD activity was significantly lower at 12 hr after the Arg injection as compared with the controls. Allopurinol treatment markedly reduced the serum amylase elevation (12.631 ± 2.257 units/liter at 24 hr) and prevented the increase in tissue MDA concentration (0.55 ± 0.09 nM/mg protein at 48 hr). Both doses of allopurinol significantly ameliorated the pancreatic edema, necrosis, and inflammation at 48 hr after Arg administration. Oxygen-derived free radicals are generated at an early stage of Arg-induced acute pancreatitis. Prophylactic allopurinol treatment prevents the generation of reactive oxygen metabolites, reduces the serum amylase concentration, and exerts a beneficial effect on the development of histopathological changes.

Effects of bile acids on pancreatic ductal bicarbonate secretion in guinea pig

Background and aims: Acute pancreatitis is associated with significant morbidity and mortality. Bile reflux into the pancreas is a common cause of acute pancreatitis and, although the bile can reach both acinar and ductal cells, most research to date has focused on the acinar cells. The aim of the present study was to investigate the effects of bile acids on HCO3− secretion from the ductal epithelium. Methods: Isolated guinea pig intralobular/interlobular pancreatic ducts were microperfused and the effects of unconjugated chenodeoxycholate (CDC) and conjugated glycochenodeoxycholate (GCDC) on intracellular calcium concentration ([Ca2+]i) and pH (pHi) were measured using fluorescent dyes. Changes of pHi were used to calculate the rates of acid/base transport across the duct cell membranes. Results: Luminal administration of a low dose of CDC (0.1 mM) stimulated ductal HCO3− secretion, which was blocked by luminal H2DIDS (dihydro-4,4′-diisothiocyanostilbene-2,2′-disulfonic acid). In contrast, both luminal and basolateral administration of a high dose of CDC (1 mM) strongly inhibited HCO3− secretion. Both CDC and GCDC elevated [Ca2+]i, and this effect was blocked by BAPTA-AM (1,2-bis(o-aminophenoxy)ethane-N,N,N′,N′-tetra-acetic acid), caffeine, xestospongin C and the phospholipase C inhibitor U73122. BAPTA-AM also inhibited the stimulatory effect of low doses of CDC on HCO3− secretion, but did not modulate the inhibitory effect of high doses of CDC. Conclusions: It is concluded that the HCO3− secretion stimulated by low concentrations of bile acids acts to protect the pancreas against toxic bile, whereas inhibition of HCO3− secretion by high concentrations of bile acids may contribute to the progression of acute pancreatitis.

Polymorphism of the TNF-alpha, HSP70-2, and CD14 genes increases susceptibility to severe acute pancreatitis.

Objectives: Proinflammatory cytokines and heat shock proteins play fundamental roles in the pathogenesis of acute pancreatitis. We studied whether polymorphisms of the tumor necrosis factor α (TNF-α), heat shock protein 70-2 (HSP70-2), and CD14 genes correlate with the severity of acute pancreatitis. Methods: Patients with acute pancreatitis (n = 77) of mixed etiology were grouped according to the severity of the disease on the basis of the Ranson scores. Healthy blood donors (n = 71) served as controls. TNF-α-308 polymorphism was determined by NcoI RFLP, HSP70-2 polymorphism by PstI RFLP, and CD14-159 polymorphism by melting point analysis. Results: There was a moderate increase in the frequency of the TNF1/2 genotype (P = 0.046) among patients with severe acute pancreatitis as compared with those with mild disease. A more significant increase was observed in the frequency of the HSP70-2 G allele between groups of patients with mild or severe pancreatitis (18.9% vs. 53%; P < 0.001). Conversely, the A/A genotype was markedly more frequent among the patients with mild pancreatitis (P < 0.0001). There was no significant correlation between CD14-159 promoter polymorphism and the severity of pancreatitis. Conclusion: High frequencies of the HSP70-2 G and the TNF-α -308 A alleles were associated with risk of severe acute pancreatitis. Genotype assessments may be important prognostic tools to predict disease severity and the course of acute pancreatitis. Therefore, genotype assessments may also be used to guide treatment or to identify risk populations for severe acute pancreatitis.

The role of nitric oxide in edema formation in L-arginine-induced acute pancreatitis.

Introduction Nitric oxide (NO) has been implicated in the regulation of the pancreatic circulation, the promotion of the capillary integrity, and the inhibition of leukocyte adhesion. Aims To investigate the rates of changes in the pancreatic constitutive NO synthase (cNOS) and inducible NOS (iNOS) activities and the role of NO in the vascular permeability changes during the development of L-arginine (Arg)–induced acute pancreatitis. Methodology Acute pancreatitis was induced in male Wistar rats by injecting 250 mg/100 g body weight of Arg i.p. twice at an interval of 1 hour, as a 20% solution in 0.15 M NaCl (group I). The control rats received the same quantity of glycine (group II). In group III, 30 mg/kg NG-nitro-L-arginine methyl ester (L-NAME) was injected i.p. 19 hours after the first Arg injection. The rats were killed at 6, 12, 24, or 48 hours following Arg administration, and the plasma amylase concentration and the pancreatic weight/body weight (pw/bw) ratios were evaluated. NOS activity was determined via the conversion of L-14C-Arg monohydrochloride to 14C-citrulline. The vascular permeability was examined by means of the extravasation of Evans blue dye (20 mg/kg bw) into the pancreatic tissue. Results The serum amylase level was already increased at 6 hours in group I animals, peaked at 12 hours after the Arg injection (11.800 ± 590 versus 6.618 ± 252 U/L in group II), and returned to the control level at 48 hours. The pw/bw ratio peaked at 24 hours in group I (6.63 ± 0.52 versus 4.02 ± 0.22 mg/g in group II) and returned to the control level at 48 hours. The cNOS activity was depleted at 6 hours in group I (0.02 ± 0.003 versus 0.23 ± 0.02 pmol/min/mg protein in group II); it then gradually increased to a level significantly higher than that in group II and decreased thereafter (0.45 ± 0.03 and 0.13 ± 0.01 pmol/min/mg protein at 24 and 48 hours). The iNOS activity was significantly increased at 24 and 48 hours versus that in group II (0.15 ± 0.05 and 0.07 ± 0.01 versus 0.04 ± 0.01 pmol/min/mg protein). The pancreatic concentration of Evans blue dye was significantly higher in group I than in group II (138.59 ± 11.04 versus 43.57 ± 2.67 (g/dry weight). Treatment with L-NAME significantly reduced the amylase activity, pw/bw, Evans blue concentration, and cNOS activity of the pancreas but did not exert any beneficial effect on the histologic score at 24 hours after the onset of pancreatitis, as compared with those values in group I (6.528 ± 673 U/L, 4.56 ± 0.65 mg/g, 86.84 ± 3.9 (g/dry weight, 0.14 ± 0.04 pmol/min/mg protein). Conclusion Endogenous NO is involved in the formation of pancreatic edema in Arg-induced acute pancreatitis by increasing the vascular permeability and protein extravasation. L-NAME treatment decreased the cNOS activity and edema formation but did not prevent the histologic damage in Arg-induced acute pancreatitis.

Diagnostic relevance of procalcitonin, IL-6, and sICAM-1 in the prediction of infected necrosis in acute pancreatitis

SummaryBackground. Infected pancreatic necrosis (IPN) is an absolute indication for surgical intervention, therefore an early and accurate laboratory diagnosis is necessary to confirm the infection. The aim of the study was to analyze the clinical value of procalcitonin (PCT) for the prediction of infected necrosis, in comparison with interleukin-6 (IL-6) and sICAM-1.Patients and Methods. A total of 30 patients were investigated; 10 patients with sterile pancreatic necrosis (SPN), 10 with IPN, and 10 with sepsis of different origin. The concentrations of PCT in the patients’ sera were measured by immunoluminometric assay (BRAHMS Diagnostica, Berlin, Germany, PCTLumitest), the IL-6 concentrations by bioassay, applying the B-9 cell line, and the sICAM-1 levels by enzyme-linked immunosorbent assay (ELISA) (R&D). PCT was determined in cell lysates by ECL Western blot.Results. PCT was found in relatively high concentrations (8.5±4.8 ng/mL) only in patients with infected pancreatic necrosis, and in patients with sepsis of different origin (15±5.4 ng/mL). Positive values (>1 ng/mL) preceded positive bacterial results from either blood or surgical samples. None of the serum samples of patients with SPN exhibited PCT concentrations higher than 1.2 ng/mL. In contrast, IL-6 and sICAM-1 were overproduced in both types (infected and sterile) of pancreatic necrosis, and their levels remained elevated for several days even after surgical elimination of the infected focus (widespread necrosectomy and continuous lavage). Sensitivity, specificity, and positive predictive values for discriminating IPN from SPN was 90, 100, and 100% for PCT (p<0.0001); 100, 20, and 55% for IL-6 (p 0.474 n.s.) and 90, 10, and 50% for sICAM-1 (p 1.000 n.s.). Immunoblotting revealed no PCT in patients’ leukocytes, or in human endothelial cell lines. Conclusion. Elevated serum IL-6 and sICAM-1 levels are characteristic in systemic inflammatory response syndrome (SIRS) of either infectious or noninfectious origin. In contrast, the PCT level is an accurate, readily available parameter that allows the discrimination of IPN, and is a helpful marker facilitating a decision concerning surgical intervention.

Genetic Polymorphisms of NOD1 and IL-8, but not Polymorphisms of TLR4 Genes, Are Associated with Helicobacter pylori-Induced Duodenal Ulcer and Gastritis

Background:  Intracellular pathogen receptor NOD1 is involved in the epithelial cell sensing Helicobacter pylori, which results in a considerable interleukin (IL)‐8 production. The aim of this study was to evaluate the relationship between NOD1 and IL‐8 genetic polymorphisms and the development of H. pylori‐induced gastritis and duodenal ulcer (DU), as compared with TLR4 polymorphisms.

NF-κB activation is detrimental in arginine-induced acute pancreatitis

The transcription factor nuclear factor kappaB (NF-kappaB) has been shown to have a critical role in the pathogenesis of sodium taurocholate- and cerulein-induced acute pancreatitis by regulating the expression of many proinflammatory genes in the pancreas. Heat shock proteins (HSPs), on the other hand, protect the pancreas against cellular damage. The aims of the present study were: (i) to investigate pancreatic NF-kappaB activation, proinflammatory cytokine synthesis, and cytoprotective HSP induction during L-arginine- (Arg-) induced acute pancreatitis in rats, and (ii) to establish whether pretreatment with pyrrolidine dithiocarbamate (PDTC) or methylprednisolone (MP) can block the activation of pancreatic NF-kappaB and determine their effects on the severity of Arg-induced acute pancreatitis. The dose-response (3 or 4 g/kg) and time-effect (0.5-96 h) curves relating to the action of Arg on pancreatic NF-kappaB activation and IL-1beta, TNF-alpha, HSP60, and HSP72 synthesis were evaluated. Various doses of PDTC or MP were administered 1 h before the induction of pancreatitis. We demonstrated that Arg specifically and dose-dependently induces pancreatitis, activates NF-kappaB (only the 3 g/kg dose) and proinflammatory cytokine synthesis, and increases the expressions of HSP60 and HSP72 in the pancreas of rats. The lower dose of Arg induced a less severe pancreatitis, but larger increases in the levels of HSPs. The present work supports and extends earlier observations that NF-kappaB activation is a common mechanism in acute pancreatitis, although it is dose dependent and occurs at a later stage in Arg-induced pancreatitis as compared with other models. PDTC and MP pretreatment dose-dependently blocked NF-kappaB activation and proinflammatory cytokine expression and ameliorated many of the examined laboratory (the pancreatic weight/body weight ratio, the pancreatic myeloperoxidase activity, the pancreatic contents of protein, amylase and trypsinogen, the degrees of lipid peroxidation and protein oxidation, and the nonprotein sulfhydryl group content) and morphological parameters of the disease. These findings suggest that pretreatment with PDTC or MP has an anti-inflammatory effect during Arg-induced pancreatitis, which is at least partly mediated by the inhibition of NF-kappaB activation and proinflammatory cytokine synthesis. The increased levels of HSPs most probably act to limit the severity of the disease.

Quality of life assessment after pancreatic enzyme replacement therapy in chronic pancreatitis

GOALS To evaluate the quality of life (QoL) of patients with chronic pancreatitis before and after pancreatic enzyme replacement therapy in a prospective, multicentre, follow-up study. STUDY Two groups of patients were evaluated. Group 1 consisted of 31 patients with newly diagnosed chronic pancreatitis who had never been treated with pancreatic enzyme preparations. Group 2 consisted of 39 patients whose disease was diagnosed on average 3.4 years before the start of the study. The latter group of patients had undergone pancreatic enzyme replacement therapy, but during follow-up this treatment proved to be insufficient. The dose of pancreatic enzyme replacement therapy was tailored in accordance with the degree of pancreatic exocrine insufficiency measured by means of exocrine pancreatic function tests. A modified European Organizaton for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30) was used to assess QoL. RESULTS The social functioning and financial strain were significantly better, while the levels of hope and confidence were significantly reduced in group 1 compared with group 2. A significant gain in body weight and a significantly reduced defecation rate were found in both groups one month after the beginning of the pancreatic enzyme replacement therapy when compared with the pretreatment values. The prevalence of general and disease-specific symptoms and the intensity of pain were reduced in both groups after one month of enzyme substitution therapy. The working ability, the financial strain and the overall QoL scores were improved significantly in both groups, while the cognitive functioning score was found to be significantly improved during the follow-up only in group 1. The overall increase in the QoL score correlated significantly with the increase in body weight and the decrease in defecation number in both groups. CONCLUSIONS Pancreatic enzyme replacement therapy in patients with chronic pancreatitis not only reduced the extent of steatorrhea and pain, but also significantly improved a variety of other symptoms and the patients QoL. Individually tailored enzyme replacement therapy improved the QoL not only in the untreated chronic pancreatitis patients, but also in the inadequately treated group. This study demonstrated that the EORTC QLQ-C30 questionnaire, with the addition of two further questions about steatorrhea, is a useful tool for the evaluation of QoL in patients with chronic pancreatitis.

The possible role of F-18 FDG positron emission tomography in the differential diagnosis of focal pancreatic lesions

Purpose To compare the diagnostic values of different methods for the differentiation of malignant from benign pancreatic lesions. Methods In 22 patients with focal pancreatic lesions, the carbohydrate antigen (CA) 19-9 level was measured; abdominal ultrasound (US), computed tomography (CT), endoscopic retrograde cholangiopancreatography (ERCP), and F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) were performed; and the value of these methods were analyzed for their use in cancer diagnosis. Results Malignant lesions were identified in six patients and verified by surgery or clinical follow-up. The CA 19-9 level was elevated in four of the five patients examined (sensitivity, 80%). In all six cases, US and CT revealed hypoechogenic and hypodense areas (sensitivity, 100%). In one patient, ERCP was unsuccessful but yielded true-positive results in three others (sensitivity, 60%). The sensitivity of FDG PET was 100%. Sixteen focal cases of pancreatic disease proved to be benign. The CA 19-9 level was elevated in four of them (specificity, 73%). Hypoechogenic and hypodense areas were evident on US and CT in eight patients. The specificity of CT was 50% (8 of 16 cases). The specificity of US was 47% (7 of 15 cases). The specificity of successful ERCP was 92%. Fourteen negative FDG-PET results were truly negative. In two patients, however, the PET findings proved to be falsely positive (specificity, 88%). Conclusions FDG-PET is an effective tool to differentiate malignant from benign focal pancreatic lesions. In persons with focal pancreatic hypoechogenic or hypodense lesions detected by CT or US and an elevated CA 19-9 level, FDG PET should be the next step in the diagnostic strategy.