Changes in the expression and distribution of the inducible and endothelial nitric oxide synthase in mucosal biopsy specimens of inflammatory bowel disease

OBJECTIVE: The role of nitric oxide (NO) in the pathophysiology of inflammatory bowel disease (IBD) is controversial. The aim of this study was to investigate the expression and localization of nitric oxide synthase isoforms (iNOS, eNOS) in IBD colonic mucosa. MATERIAL AND METHODS: Forty-four patients with IBD (24 ulcerative colitis (UC), 20 Crohn's disease (CD) and 16 controls) were investigated by colonoscopy. iNOS and eNOS in tissue sections was demonstrated by histochemistry (NADPH-diaphorase reaction) and immunohistochemistry. Cell type analysis and quantitative assessment of the iNOS immunoreactive (IR) cells and densitometry of iNOS in immunoblots were also performed. RESULTS: iNOS-IR cells were significantly numerous in inflamed mucosa of UC (64+/-4 cells/mm2) than in CD (4+/-2 cells/mm2). iNOS-IR/CD15-IR cells showed significant elevation in inflamed (i) versus uninflamed (u) UC mucosa (UCu 8+/-3%, UCi 85+/-10%) In CD, the percentage of iNOS-IR/CD68-IR cells was lower in inflamed sites (CDu 23+/-8%, CDi 4+/-3%). Immunoblot of biopsies revealed significant elevation of iNOS in active UC compared with uninflamed sites, whereas in CD no significant changes were detected. Differences were observed in eNOS and endothelial marker CD31 immunoreactivity. In patients with UC and in controls the ratios of eNOS/CD31-IR vessels were 82.3% and 92.0% respectively, whereas in CD the ratio was 8.3% with a concomitantly significant increase of CD31-IR vessels. The distribution and morphological characteristics of the NOS-IR inflammatory cells and endothelia were similar to those showing NADPH-diaphorase reactivity. CONCLUSIONS: Differences observed in the expression and distribution of NOS isoforms in immune and endothelial cells may contribute to better understanding of the structural and physiological changes in UC and CD.     

Changes in the expression and distribution of the inducible and endothelial nitric oxide synthase in mucosal biopsy specimens of inflammatory bowel disease

Objective The role of nitric oxide (NO) in the pathophysiology of inflammatory bowel disease (IBD) is controversial. The aim of this study was to investigate the expression and localization of nitric oxide synthase isoforms (iNOS, eNOS) in IBD colonic mucosa. Material and methods Forty-four patients with IBD (24 ulcerative colitis (UC), 20 Crohn's disease (CD) and 16 controls) were investigated by colonoscopy. iNOS and eNOS in tissue sections was demonstrated by histochemistry (NADPH-diaphorase reaction) and immunohistochemistry. Cell type analysis and quantitative assessment of the iNOS immunoreactive (IR) cells and densitometry of iNOS in immunoblots were also performed. Results iNOS-IR cells were significantly numerous in inflamed mucosa of UC (64±4 cells/mm²) than in CD (4±2 cells/mm²). iNOS-IR/CD15-IR cells showed significant elevation in inflamed (i) versus uninflamed (u) UC mucosa (UC_u 8±3%, UC_i 85±10%) In CD, the percentage of iNOS-IR/CD68-IR cells was lower in inflamed sites (CD_u 23±8%, CD_i 4±3%). Immunoblot of biopsies revealed significant elevation of iNOS in active UC compared with uninflamed sites, whereas in CD no significant changes were detected. Differences were observed in eNOS and endothelial marker CD31 immunoreactivity. In patients with UC and in controls the ratios of eNOS/CD31-IR vessels were 82.3% and 92.0% respectively, whereas in CD the ratio was 8.3% with a concomitantly significant increase of CD31-IR vessels. The distribution and morphological characteristics of the NOS-IR inflammatory cells and endothelia were similar to those showing NADPH-diaphorase reactivity. Conclusions Differences observed in the expression and distribution of NOS isoforms in immune and endothelial cells may contribute to better understanding of the structural and physiological changes in UC and CD.     

Endogenous endothelial nitric oxide synthase-derived nitric oxide is a physiological regulator of myocardial oxygen consumption

Our objective was to determine the precise role of endothelial nitric oxide synthase (eNOS) as a modulator of cardiac O2 consumption and to further examine the role of nitric oxide (NO) in the control of mitochondrial respiration. Left ventricle O2 consumption in mice with defects in the expression of eNOS [eNOS (-/-)] and inducible NOS [iNOS (-/-)] was measured with a Clark-type O2 electrode. The rate of decreases in O2 concentration was expressed as a percentage of the baseline. Baseline O2 consumption was not significantly different between groups of mice. Bradykinin (10(-4) mol/L) induced significant decreases in O2 consumption in tissues taken from iNOS (-/-) (-28+/-4%), wild-type eNOS (+/+) (-22+/-4%), and heterozygous eNOS(+/-) (-22+/-5%) but not homozygous eNOS (-/-) (-3+/-4%) mice. Responses to bradykinin in iNOS (-/-) and both wild-type and heterozygous eNOS mice were attenuated after NOS blockade with N-nitro-L-arginine methyl ester (L-NAME) (-2+/-5%, -3+/-2%, and -6+/-5%, respectively, P<0.05). In contrast, S-nitroso-N-acetyl-penicillamine (SNAP, 10(-4) mol/L), which releases NO spontaneously, induced decreases in myocardial O2 consumption in all groups of mice, and such responses were not affected by L-NAME. In addition, pretreatment with bacterial endotoxin elicited a reduction in basal O2 consumption in tissues taken from normal but not iNOS (-/-)-deficient mice. Our results indicate that the pivotal role of eNOS in the control of myocardial O2 consumption and modulation of mitochondrial respiration by NO may have an important role in pathological conditions such as endotoxemia in which the production of NO is altered.     

Autoantibodies to neutrophil cytoplasmic (ANCA) and endothelial cell surface antigens (AECA) in chronic inflammatory bowel disease

Sera from 103 patients with chronic inflammatory bowel disease (IBD) were tested prospectively for antibodies against neutrophil cytoplasmic antigens (anti-neutrophil cytoplasm antibodies, ANCA) and endothelial cell surface antigens (anti-endothelial cell antibodies, AECA) by indirect immunofluorescence (IIF) and assays based on whole fixed neutrophils, purified neutrophil enzyme substrates and human umbilical vein endothelial cells. Using IIF, ANCA were found in 26 IBD sera (25%) and in none of 51 controls. Twenty-two positive sera (85%) were from patients with ulcerative colitis (UC). The pattern of distribution of immunofluorescence was always perinuclear (P-ANCA). A majority of UC patients positive for these autoantibodies (68%) had active colitis, but none had evidence of vasculitis. Using a whole neutrophil ELISA, binding was demonstrable in 73% of UC sera compared to 27% of Crohn's (CD) sera and only 4% of controls. Unlike vasculitis sera, UC sera with P-ANCA did not bind strongly to myeloperoxidase (MPO). Forty-five per cent of IBD sera tested positive for IgG AECA in an endothelial cell ELISA, compared to seven of 51 (14%) controls. Binding correlated with both active and extensive colitis. A type of P-ANCA, in most cases distinct from MPO-specific P-ANCA observed in vasculitis, is detected in a significant proportion of patients with UC, but rarely Crohn's colitis and therefore may be of differential diagnostic value. IgG AECA are also frequent in CIBD sera but are less disease specific than ANCA. (Aust NZ J Med 1992; 22: 652ndash;659.)     

Co-expression and modulation of neuronal and endothelial nitric oxide synthase in human endothelial cells

Despite originally identified in neurones, the neuronal type of nitric oxide synthase (nNOS) is present also in cardiac and skeletal myocytes. Whether nNOS is functionally expressed in human endothelial cells--as the endothelial enzyme (eNOS)--is unknown. Human umbilical vein endothelial cells (HUVEC) were studied under control culture conditions and after 48 h treatment with cytomix (human tumour necrosis factor-alpha, interferon-gamma and E. coli endotoxin). We tested: (i) localisation and expression of nNOS and eNOS proteins by immunostaining and immunoblotting; (ii) activity of nNOS and eNOS by measuring L-arginine to L-citrulline conversion with 1-(2-trifluoromethylphenyl)imidazole (TRIM), a specific nNOS antagonist, in sub-cellular fractions; (iii) intracellular cGMP levels, as a marker for nitric oxide production, after TRIM pre-treatment, by radioimmunoassay. nNOS protein was expressed in the cytosolic fraction and immunolocalised in cultured HUVEC, and co-localised with the eNOS protein in frozen sections of the human umbilical cord. nNOS protein contributed to total L-citrulline production as TRIM selectively and dose-dependently reduced L-citrulline synthesis in the cytosolic but not particulate fraction of HUVEC. Similarly, TRIM reduced intracellular cGMP content both at baseline and after stimulation with a calcium ionophore. Cytomix down-regulated the expression and function of both nNOS and eNOS while no inducible NOS (iNOS) was detected. In conclusion, a functional neuronal type of NOS is co-expressed with the endothelial NOS type in HUVEC, suggesting a possible role for nNOS in regulation of blood flow.     

Loss of fragile histidine triad protein expression in inflammatory bowel disease

INTRODUCTION Inflammatory bowel disease (IBD) is a collection of chronic idiopathic in? ammatory disorders of the intestine and/or colon, including two independent diseases: ulcerative colitis (UC) and Crohn’s disease (CD)[1]. Up to now, the complex etio…     

Increased vascular expression of iNOS at day but not at night in asthmatic subjects with increased nocturnal airway obstruction.

Nitric oxide production by endothelial cells may have important consequences for the development of airway inflammation as well as for airway obstruction. The present study investigated whether the expression of vascular inducible nitric oxide synthase (iNOS) and endothelial nitric oxide synthase (eNOS) in human bronchi differs between asthmatic and healthy subjects, and whether it shows a circadian rhythm, especially in subjects with increased nocturnal airway obstruction. Bronchial biopsy samples were taken at 16:00 and 04:00 h from 13 healthy and 25 asthmatic subjects, 18-45 yrs. Biopsy samples were snap-frozen and double-immunostained for iNOS and eNOS in combination with a common vascular antigen (CD31). The degree of immunopositivity was expressed as a percentage of CD31-positive vessels encountered in complete biopsy sections. Asthmatic subjects showed greater iNOS expression than healthy controls: 23+/-15 versus 7+/-17% (mean+/-SD) at 16:00 h (p<0.001) and 19+/-15 versus 8+/-11% at 04:00 h (p<0.05). Asthmatic subjects with a fall in forced expiratory volume in one second of >10% of the predicted value between 16:00 and 04:00 h showed greater iNOS expression at 16:00 than at 04:00 h: 32+/-16 versus 20+/-13% (p<0.05). eNOS expression did not differ between healthy controls and asthmatic patients, nor did it differ between 16:00 and 04:00 h. It is suggested that asthmatic subjects with increased nocturnal airway obstruction demonstrate increased activation of inducible nitric oxide synthase during the day. The resulting nitric oxide production might protect against airway obstruction during the day. However, at night, nitric oxide production is probably insufficient to counterbalance the bronchoconstricting forces.     

Effects of different levels of exercise volume on endothelium-dependent vasodilation: roles of nitric oxide synthase and heme oxygenase

The objective of this study was to examine the effects of moderate and high levels of exercise volume on endothelium-dependent vasodilation and associated changes in vascular endothelial/inducible nitric oxide synthase (eNOS and iNOS) and heme oxygenase (HO). Male Sprague-Dawley rats were assigned to sedentary control, acute (2 weeks), or chronic (6 weeks) treadmill running at moderate intensity (50% maximal aerobic velocity) with different durations of exercise episodes: 2 h/d (endurance training, moderate volume) and 3 h/d (intense training, high volume). Endothelium-dependent vascular function was examined in isolated thoracic aorta. Co-localization and contents of aortic eNOS/iNOS and HO-1/HO-2 were determined with immunofluorescence and Western blotting. Compared with sedentary controls, rats subjected to acute and chronic endurance training showed enhanced endothelium-dependent relaxation (p<0.01). Whereas acetylcholine-induced dilation was inhibited completely by NOS inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME) in sedentary controls, the dilation in the training groups was only partly blocked by L-NAME (inhibition was 98+/-3%, 79+/-6%, and 77+/-5% in sedentary control, acute, and chronic training groups, respectively, p<0.01). The remnant dilation in the training groups was further inhibited by HO inhibitor protoporphyrin IX zinc, with concomitant elevation in aortic eNOS as well as HO-1 and HO-2. In contrast to endurance exercise, high-volume intense training resulted in mild hypertension with significant impairment in endothelium-dependent vasodilation and profuse increases in aortic iNOS and eNOS (p<0.01). In conclusion, endothelium-dependent vasodilation is improved by endurance exercise but impaired by chronic intense training. Elevations of vascular eNOS and HO-1/HO-2 may contribute to enhanced vasodilation, which can be offset by intense training and elevation in vascular iNOS.     

Endothelial nitric oxide synthase protein is reduced in the renal medulla of two-kidney, one-clip hypertensive rats

OBJECTIVE : We studied endothelial nitric oxide synthase (eNOS) expression in the kidneys of two-kidney, one-clip renal hypertensive rats (2K1C) before and after removal of the clip (unclipping, UC). We hypothesised that the haemodynamic changes induced by 2K1C and UC would change eNOS expression in the two kidneys. METHODS : Six weeks after inducing 2K1C, mean arterial pressure (MAP) was measured in conscious rats and hypertension reversed by UC. Left and right kidney eNOS protein in cortex and outer medulla was semi-quantified using immunoblotting. Groups were; normotensive (n = 10), 2K1C (n = 10), 3 h (n = 10), 48 h (n = 7) and 4 weeks (n = 7) after UC. The effect of 7 days of aldosterone or angiotensin II (Ang II) infusion on medullary eNOS protein was tested as well as the effect of L-NAME (nitric oxide (NO) synthase inhibitor) on medullary blood flow (MBF) in anaesthetized 2K1C. RESULTS : UC reduced MAP from 178 +/- 5 to 134 +/- 3 mmHg after 3 h and normalized MAP at 48 h and 4 weeks. The medulla from 2K1C kidneys contained about 33% less eNOS protein compared with normotensive kidneys (P < 0.05). This difference was still evident at 3 h (P < 0.05), but completely reversed at 48 h and 4 weeks after UC. Similar levels of eNOS expression were seen in the left and right kidney at all time points. Cortical eNOS was increased in kidneys from 2K1C. Neither Ang II nor aldosterone affected eNOS expression in the medulla. MBF was under similar influence of NO in 2K1C compared with normotensive kidneys. CONCLUSIONS : 2K1C is associated with reduced levels of eNOS protein in the renal medulla of both clipped and contralateral kidney. eNOS expression in right and left kidney was not changed despite expected large changes in haemodynamics of the two kidneys. The reduced level of eNOS may be associated with a reduction in MBF and thus be of patho-physiological importance in renovascular hypertension.     

Expression of platelet-derived endothelial cell growth factor in inflammatory bowel disease

Background: Platelet-derived endothelial cell growth factor (PD-ECGF) is reported to be highly expressed in tumors and inflammatory tissues, but its expression and role in inflammatory bowel disease (IBD) are still unclear. In this study we examined the location and tissue density of cells immunoreactive for PD-ECGF in the colonic mucosa of IBD. Methods: Paraffin-embedded sections of colonic tissue from patients with ulcerative colitis (UC) or Crohn's disease (CD) were immunostained for PD-ECGF. As controls, noninflamed mucosa of IBD, as well as normal colonic mucosa from patients with colorectal cancer, were used. Also, cancer tissues were evaluated. In addition, changes in the expression of PD-ECGF in human umbilical vein endothelial cells (HUVEC) after treatment with inflammatory cytokines and angiogenic factors, as well as after coculture with colon cancer cell lines, were evaluated by flow cytometry. Results: In normal colonic mucosa and noninflamed mucosa of IBD, PD-ECGF expression was negligible. In inflamed colonic mucosa, strong expression was observed, predominantly in macrophages and fibroblasts. Vascular endothelial cells of the inflamed colonic mucosa, but not of normal colonic mucosa or of neoplastic tissues, stained for PD-ECGF, and the microvessel density was significantly increased in the severely inflamed mucosa. Flow cytometry demonstrated that PD-ECGF was constitutively expressed in HUVEC. Inflammatory cytokines and vascular endothelial growth factor (VEGF) increased its expression, whereas basic fibroblast growth factor (bFGF) decreased it. Coculture with colon cancer cell lines in direct contact, but not in those without contact, also resulted in an important decrease in the expression of PD-ECGF in HUVEC. Conclusions: Autocrine production of PD-ECGF by endothelial cells may be a mechanism of inflammatory angiogenesis, but not tumor angiogenesis, and may be particularly important for the maintenance of damaged vasculature in IBD. Received: September 17, 2001 / Accepted: September 6, 2002 Acknowledgments. This study was supported partly by a Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science, and Technology of Japan, and partly by a grant from the Ministry of Health, Labour, and Welfare of Japan. Reprint requests to: S. Saito, Present address: Department of Surgery, Chigasaki Municipal Hospital, 5-15-1 Honson, Chigasaki 253-0042, Japan     

VEGF, basic-FGF, and TGF-beta in Crohn's disease and ulcerative colitis: a novel mechanism of chronic intestinal inflammation

OBJECTIVE: Inflammatory bowel disease (IBD), the precise etiology of which remains unknown, is comprised of two forms of chronic intestinal inflammation; ulcerative colitis (UC) and Crohn's disease (CD). Recent evidence increasingly suggests that IBD is the result of dysfunctional immunoregulation manifested by inappropriate production of mucosal cytokines. An abnormal microcirculatory system has also been implicated in its pathogenesis. To elucidate the mechanism of ischemic change in IBD, we assesse serum concentration levels of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (b-FGF), and plasma level of endothelin-1 (ET-1). We also investigated the expression of VEGF, b-FGF, and transforming growth factor-beta1,2,3 (TGF-beta1,2,3) in tissue by immunostaining. METHODS: Blood samples were obtained from 11 patients with UC, 11 patients with CD, and 10 patients as controls. Paraffin-embedded samples were used for an immunohistochemical study. RESULTS: The concentration levels (in picograms per milliliter) were as follows: for ET-1, UC: 127+/-47.0, CD: 167.3+/-35.1, and controls (asthma: 38.5+/-23.8, p < 0.01; diverticulitis: 40.5+/-25.6, p < 0.01), for b-FGF, UC: 9.2+/-1.9, CD: 9.1+/-1.5, and controls (asthma: 5.0+/-0, p < 0.01; diverticulitis: 5.0+/-0, p < 0.01), for VEGF, UC: 659.8+/-181.0, CD: 740.0+/-182.3, and controls (asthma: 193.7+/-58.7, p < 0.01; diverticulitis: 199.6+/-59.7, p < 0.01). The levels of VEGF and b-FGF were significantly higher in active IBD than those in the controls. There was a significant positive correlation among the serum levels of VEGF and b-FGF and the plasma level of ET-1; that is, elevated VEGF, b-FGF, and ET-1 levels correlated well with each other. Immunohistochemical studies showed increased venula in the submucosa and lamina propria. Overexpression of VEGF and b-FGF in endothelial cells was revealed and TGF-beta2 and TGF-beta3 were found in inflammatory cells of active IBD, but no change was observed around the vessels in the controls. CONCLUSIONS: It is suggested that the reciprocal reaction of these cytokines may contribute to angiogenesis in IBD b inducing intestinal ischemia through vasoconstriction.     

Circulating levels of leptin, adiponectin, resistin, and ghrelin in inflammatory bowel disease

BACKGROUND: There is evidence that adipocytokines play an important role in metabolism and in inflammation. Because human metabolism dramatically changes in inflammatory bowel disease (IBD) and chronic inflammation is the hallmark of the disease, we studied serum levels of leptin, adiponectin, resistin, and ghrelin in patients with ulcerative colitis (UC) and Crohn's disease (CD) in comparison with healthy controls (HC). METHODS: Leptin, adiponectin, resistin, and active ghrelin serum levels were measured in 100 IBD patients (46 UC and 54 CD) and in 60 matched HC using commercially available enzyme-linked immunosorbent assays. Leptin, adiponectin, resistin, and ghrelin levels were correlated with disease activity, type, localization, and treatment. RESULTS: Mean serum leptin levels were 10.6+/-2.0 ng/mL in UC patients, 12.5+/-2.6 ng/mL in CD patients, and 15.0+/-1.8 ng/mL in HC (P=.01). Mean serum adiponectin levels were 9514.8+/-787.8 ng/mL in UC patients, 7651.1+/-613 ng/mL in CD patients, and 7270.6+/-559.4 ng/mL in HC (P=.05). Mean serum resistin levels were 21.2+/-2.2 ng/mL in UC patients, 18.7+/-1.6 ng/mL in CD patients and 11.8+/-0.6 ng/mL in HC (P=.0002). Mean serum ghrelin levels were 48.2+/-4.2 pg/mL in UC patients, 49.4+/-4.6 pg/mL in CD patients and 14.8+/-3.0 pg/mL in HC (P<.0001). Serum levels of these adipocytokines were not correlated with either C-reactive protein levels or the clinical indices of activity. No association between serum adipocytokines levels and disease localization in both UC and CD patients was found. Only serum ghrelin was significantly higher in ileal compared with colonic CD (P=.04). CONCLUSIONS: Serum levels of adiponectin, resistin, and active ghrelin are increased whereas serum levels of leptin are decreased in patients with IBD. Further studies are needed to elucidate the role of adipocytokines in IBD.     

Dipeptidyl peptidase IV (DP IV, CD26) in patients with inflammatory bowel disease

BACKGROUND: Dipeptidyl peptidase IV (DP IV, CD26), a serine protease with broad tissue distribution and known activity in serum, participates in T cell activation and promotes a Th1 cytokine response, a function in part attributable to its enzymatic activity. We hypothesized that the activity of DP IV in serum and expression of CD26/DP IV in lymphocytes may be altered in patients with inflammatory bowel disease (IBD). METHODS: Serum DP IV activity and CD26 (DP IV)-positive peripheral blood lymphocytes were measured in 110 patients with IBD (Crohn disease (CD): n = 63, ulcerative colitis (UC): n = 47). Additionally, T cell activation antigens (CD25, CD95) and costimulatory molecules (CD28) were evaluated. The same analyses were carried out in healthy volunteers (HC, n = 28). Thirty-nine patients with CD and 28 patients with UC were reassessed 3-6 months after the first visit. RESULTS: In patients with IBD, the DP IV activity in serum was reduced (mean +/- s (standard deviation): 52.8 U/l +/- 16.9 (CD) and 55.7 +/- 15.1 U/l (UC) versus 71.9 +/- 18.4 (HC), P < 0.001). Furthermore, patients with IBD had higher numbers of CD26-positive cells coexpressing CD25 and a higher surface expression of CD26 (DP IV) (mean fluorescence intensity, mean 57.1 (CD) and 59.8 (UC) versus 29.9 (HC), P < 0.001). The DP IV activity in serum showed an inverse correlation with known disease activity scores as well as with the concentrations of orosomucoid in serum. CONCLUSION: The changes of DP IV in patients with IBD highlight alterations at an interface between immune function and metabolism of peptide hormones, with potential importance for the pathophysiology of IBD. Furthermore, these changes may help to refine the assessment of IBD activity.     

An endothelial nitric oxide synthase inhibitor aggravates CDL-induced acute pancreatitis in rats.

To clarify the role of nitric oxide (NO) in the development and progression of acute pancreatitis, we investigated the effect of different NO synthase inhibitors and NO donors on experimental pancreatitis in rats. Closed duodenal loop (CDL)-induced pancreatitis was produced in male Wistar rats, and the animals were treated with normal saline, the NO-synthase substrate L-arginine, the NO donor S-nitroso-N-acetylpenicillamine, aminoguanidine, which is a more powerful inhibitor of inducible NO synthase (iNOS) than is endothelial NO synthase (eNOS), and N-nitro-L-arginine methyl ester (L-NAME), a more powerful inhibitor of eNOS than of iNOS. All drugs were infused intravenously during a period of 6 or 12 h in each group. Pancreatic tissue was removed at 6 and 12 h after creating the CDL. L-Arginine, S-nitroso-N-acetyl-penicillamine, and aminoguanidine treatment had no effect on the elevation of serum pancreatic enzymes, whereas L-NAME administration significantly exacerbated their elevation. Pathologically, L-NAME treatment resulted in a significantly worse histologic score at 6 and 12 h, especially in terms of the degree of hemorrhage, acinar cell necrosis, and microvascular thrombosis. Addition of L-arginine clearly reversed the effect of L-NAME. Neither the NO substrate nor NO donor could inhibit the progression of hemorrhagic pancreatitis in CDL-induced pancreatitis. Aminoguanidine had no effect on the severity of the pancreatitis. We therefore concluded that NO production by eNOS may play a significant role in preventing the development and progression of acute pancreatitis.     

Molecular cloning reveals nearly half of patients with Crohn's disease have an antibody to peroxiredoxin 6-like protein

Background and Aim: Crohn's disease (CD) is a chronic inflammatory bowel disease (IBD) of unknown etiology. We aimed to identify the etiological agent of CD using a molecular cloning strategy that was particularly focused on identifying agents causing immune abnormalities and infectious agents. Methods: We constructed a cDNA library derived from the inflamed intestinal tissue of a CD patient, and screened 1.5 million clones in this library with the serum from another typical CD patient. The expressed cDNA clones that positively reacted with the serum were then expressed as fusion proteins with glutathione S‐transferase, and western blotting was performed using the sera of 22 CD, 13 ulcerative colitis (UC), and 16 non‐IBD patients. Results: We identified nine positive clones that did not contain any viral or bacterial genomic DNA. Of these, we selected one clone (clone 50) with which the typical CD patient's serum most strongly reacted. Clone 50 is highly homologous to the antioxidant protein peroxiredoxin 6. In western blotting, the sera of 47.6% CD patients (small intestine type 80%, large and small intestine type 43%, large intestine type 0%) showed strong reactivity to clone 50, none of the UC patients were reactive to clone 50, and 18.8% of non‐IBD patients were very weakly reactive to it. We also found that the expression of peroxiredoxin 6 was significantly increased in inflamed intestinal epithelia of CD. Conclusion: The present study first showed that some CD patients have an antibody against peroxiredoxin 6‐like protein, which may be involved in the pathogenesis of CD.     

Relationship between fecal lactoferrin and inflammatory bowel disease

OBJECTIVE: Lactoferrin as a glucoprotein that can reflect the activity of neutrophil leukocytes is a specific and sensitive indicator in the evaluation of intestinal inflammation. The aim of this study was to evaluate the relationship between fecal lactoferrin and intestinal inflammation by quantitative analysis and the effect of fecal lactoferrin in measuring the activity of inflammatory bowel disease (IBD) including ulcerative colitis (UC) and Crohn's disease (CD). MATERIAL AND METHODS: A total of 177 fresh stool samples were collected from 42 active UC, 17 inactive UC, 13 active CD, 5 inactive CD, 41 infectious bowel disease, 25 irritable bowel syndrome (IBS) and 34 healthy volunteers. IBD-SCAN was used quantitatively to measure the level of fecal lactoferrin. A modified Harvey-Bradshaw Active Index was used to evaluate the activity of IBD. RESULTS: Fecal lactoferrin was 3.15+/-1.60 microg/g in healthy volunteers, 2.54+/-1.49 microg/g in IBS, 83.3+/-29.9 microg/g in infectious bowel disease, 1126.29+/-431.21 microg/g in active UC, 1035.25+/-456.59 microg/g in active CD, 96.58+/-82.46 microg/g in inactive UC and 133.52+/-88.89 microg/g in inactive CD. Fecal lactoferrin was significantly higher in active IBD than in inactive IBD, IBS and infectious bowel disease. The sensitivity and specificity of fecal lactoferrin were 92% and 88%, respectively, for UC, and 92% and 80%, respectively, for CD. CCONCLUSIONS: Fecal lactoferrin is a sensitive and specific marker in measuring the activity of IBD. It provides us with a valid method in discriminating between inflammatory and non-inflammatory bowel disease. In addition, an elevated fecal lactoferrin level can lead us to exclude IBS in clinical practice.     

Serum von Willebrand factor levels in patients with inflammatory bowel disease are related to systemic inflammation

BACKGROUND: Increased levels of circulating von Willebrand factor (vWF) have been found in patients with inflammatory bowel disease (IBD); this increase may reflect either endothelial damage or systemic inflammation. Our aim was to evaluate serum vWF levels in patients with IBD and their correlation with clinical and biochemical disease activity. METHODS: We evaluated serum vWF levels in 32 patients with ulcerative colitis (UC) (10 active with increased acute-phase reactants (APR), 6 active with normal APR, 16 in remission), 27 with Crohn disease (CD) (10 active, 12 quiescent, and 5 quiescent with increased APR), and 31 healthy controls. RESULTS: Mean levels of vWF were 100.1 (standard deviation (s), 51.4) in IBD and 89.9 (s, 36.9) in controls (P = 0.33). Only five (8.47%) patients (three with active UC, one with active CD, and one with inactive CD but increased APR) showed circulating vWF levels higher than the upper limit of normal (150), compared with 1 (3.2%) of controls (P = 0.32). Among CD patients vWF levels were 80.0+/-25.4 in patients with quiescent disease and normal APR, 123.3+/-63.4 in patients with active disease (P = 0.04 versus inactive with normal APR), and 135.8+/-90.0 in patients with quiescent disease and increased APR (P = 0.059 versus inactive with normal APR). Among UC patients vWF levels were 82.7+/-35.6 in patients with quiescent disease and normal APR and 125.1+/-54.2 in those with active disease and increased APR (P = 0.002). Overall, mean vWF levels were significantly higher in patients with increased APR than in patients with normal APR (P = 0.0005) and controls (P = 0.009). CONCLUSIONS: Our data show slight but significant increases in serum vWF levels in patients with IBD, which are correlated with signs of systemic inflammation.     

Cost of early management of chronic inflammatory intestinal disease]

OBJECTIVES: The aim of this study was to assess the cost of the first management of inflammatory bowel disease (IBD) from the onset of first symptoms until 6 weeks after the diagnosis. This cost was calculated in French francs (FF) for all IBD and namely for Crohn's disease (CD), ulcerative colitis (UC), and ulcerative proctitis (UP). MATERIAL AND METHODS: Data concerning 258 patients were collected by the mean of a standardized questionnaire from 3 different sources: the patient, his general practitioner, and his gastroenterologist. RESULTS: Two hundred and fifty eight patients were included: 144 CD (55.8%), 76 UC (29.5%), 30 UP (11.6%), and 8 chronic unclassifiable colitis (CUC) (3.1%). The mean direct costs of the diagnosis (m +/- SD) were 23,116 +/- 40,820 FF for CD, 10,628 +/- 17,316 FF for UC and 3,451 +/- 2,743 FF for UP. Although unplanned hospitalizations occurred in only 38% of the patients (98/258), they represented the 3/4 of the mean costs: 78.2% for CD and 64% for UC. Indirect costs generated by days off work were 4,719 +/- 6,610 FF for CD, 2,996 +/- 6,897 FF for UC and 1,230 +/- 3,622 FF for UP. CONCLUSION: The first management of a patient with CD was twice more expensive than the one with UC and 6.5 times than the one with UP.     

Immunoglobulins and IgG subclasses in patients with inflammatory bowel disease.

BACKGROUND/AIMS: Serum immunoglobulin levels and distribution are altered in patients with inflammatory bowel disease (IBD). The purpose of this study is to examine the value of serum concentration of IgG subclasses for the diagnosis and evaluation of disease activity of IBD and to assess possible differences in the immunoglobulin changes between patients with Crohn's disease (CD) and ulcerative colitis (UC). METHODOLOGY: We measured serum IgG and IgG subclasses concentrations as well as IgA, IgM, ESR, CRP, elastase levels and granulocyte count of 96 patients with chronic IBD (69 with CD and 27 with UC) with various levels of disease activity. RESULTS: The total IgG levels in patients with UC were significantly increased, for both active and inactive disease, compared to those of patients with CD. The IgG1 concentration in patients with UC (7+/-0.77 mg/ml) was significantly higher than in patients with CD (5.6+/-0.61 mg/ml) (p<0.02). The IgG2 levels in CD were significantly higher than those of UC (4.6+/-0.64 vs. 3.8+/-0.57 mg/ml) (p<0.05). The IgG4 levels of UC patients were significantly higher than those of the CD patients (0.39+/-0.06 vs. 0.29+/-0.05 mg/ml) (p<0.05). No significant differences were found in the serum concentrations of IgG3, IgA and IgM between the two groups. There was a negative correlation between the various indices of disease activity and the concentration of IgG3 in patients with UC (p<0.01), and a positive correlation in patients with CD for IgG1 (p<0.001), IgG2 (p<0.001) and IgA (p<0.01). CONCLUSIONS: In IBD some of the IgG immunoglobulin subclass concentration changes correlate, positively or negatively, with disease activity and therefore could be used as additional markers of it. However, serum immunoglobulin levels cannot be used to differentiate between UC and CD.