leukotriene-b4 and Crohn-Disease

Crohn's disease (CD) is characterized by transmural inflammation that is most frequently located in the region of the terminal ileum. Although the physiopathological mechanisms of the disease are not yet well defined, the unregulated immune response is associated with high production of reactive oxygen species (ROS). These elements are associated with complex systems known as antioxidant defenses, whose function is ROS regulation, thereby preventing the harmful effects of these elements. However, the presence of an imbalance between ROS production and ROS elimination by antioxidants has been widely described and leads to oxidative stress. In this article, we describe the most significant findings on oxidative stress in the intestinal mucosa and peripheral blood.

Topics: Anti-Inflammatory Agents; Autoantibodies; Catalase; Crohn Disease; Humans; Hydrogen Peroxide; Inflammation; Intestinal Mucosa; Leukotriene B4; Lymphocytes; NADPH Oxidases; Neutrophils; Nitric Oxide Synthase Type II; Oxidative Stress; PPAR gamma; Probiotics; Reactive Nitrogen Species; Reactive Oxygen Species

Topics: Colitis, Ulcerative; Crohn Disease; Forecasting; Humans; Interleukin-1; Leukotriene B4; Lipoxygenase; Lipoxygenase Inhibitors; Receptors, Interleukin-1

Whatever initiates inflammation, the final message mediating cellular invasion is chemical. This consideration allows rational development of anti-inflammatory treatments. Two main classes of chemotactic mediator are recognised. Water-soluble peptides, e.g. cytokines derived from macrophages and other cells, play an important integrating part in the early recruitment of neutrophils and mononuclear cells, and in the amplification of immune responses. Lipid-soluble mediators, of which leukotriene B4 is the most highly chemotactic for neutrophils, are important in secondary amplification. In inflammatory bowel disease, we have shown evidence of increased synthesis of cytokines interleukin 1, 6 and 8. These are associated with activation of circulating monocytes in active Crohn's disease, of lamina propria macrophages in relapse of both ulcerative colitis and Crohn's disease, and development of adhesion molecules on vascular endothelium. Our studies show that interleukin 6 is selectively increased in Crohn's disease, whilst preliminary findings suggest that enhanced synthesis of interleukin 8 is particularly characteristic of ulcerative colitis. Patterns of cytokine synthesis may, therefore, be of diagnostic value. They also offer the potential for therapeutic strategies since cytokine antagonists are becoming available. We have also demonstrated increased synthesis of leukotrienes in active inflammatory bowel disease. Since leukotriene B4 is quantitatively the main chemotactic signal in the mucosa in inflammatory bowel disease during relapse, we investigated the therapeutic effect of suppressing leukotriene B4 synthesis by treating patients with fish oil (as Hi-EPA), giving 4.5 g daily of eicosapentaenoic acid. This competes for the 5-lipoxygenase enzymes, inhibiting leukotriene B4 and promoting synthesis of the less chemotactic product, LTB5.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Aminosalicylic Acids; Colitis, Ulcerative; Crohn Disease; Cytokines; Eicosapentaenoic Acid; Fish Oils; Humans; Interleukins; Leukotriene B4; Mesalamine; Sulfasalazine

Topics: Aminosalicylic Acids; Colitis, Ulcerative; Crohn Disease; Humans; Inflammatory Bowel Diseases; Leukotriene B4; Mesalamine; Prostaglandins; Sulfasalazine; Thromboxane B2

The potent mediators generated by the 5- and 15-lipoxygenation of arachidonic acid have diverse effects on smooth muscles, blood vessels, leukocytes, epithelial cells and glands, and sensory neurons, which suggest possible roles in the initiation and regulation of physiological and biochemical events. The responses to leukotrienes and related mediators are attributable to binding by stereospecific cellular receptors and consequent activation of biochemical transductional sequences analogous to those characteristic of other receptor systems. The elevated concentrations of these mediators in lesional fluids and tissues of inflammatory bowel disease and other hypersensitivity and inflammatory states are, in some instances, clearly related to the time course of development of the disease process. Systematic application of specific inhibitors and antagonists that are becoming available will define more clearly the involvement of leukotrienes in health and disease and possibly lead to new therapeutic approaches.

Topics: Arachidonate 15-Lipoxygenase; Arachidonate 5-Lipoxygenase; Colitis, Ulcerative; Crohn Disease; Humans; Hypersensitivity; Inflammation; Leukotriene B4; SRS-A

Epidemiological evidence for the role of polyunsaturated fatty-acids (PUFA) in Crohn's disease (CD) is unclear, although the key metabolite leucotriene B4 (LTB(4)) is closely linked to the inflammatory process. We hypothesized that inherited variation in key PUFA metabolic enzymes may modify susceptibility for CD.. A case-control design was implemented at three pediatric gastroenterology clinics in Canada. Children ≤20 yrs diagnosed with CD and controls were recruited. 19 single nucleotide polymorphisms (SNPs) across the ALOX5 (4) CYP4F3 (5) and CYP4F2 (10) genes, were genotyped. Associations between SNPs/haplotypes and CD were examined. A total of 431 cases and 507 controls were studied. The mean (±SD) age of the cases was 12.4 (±3.3) years. Most cases were male (56.4%), had ileo-colonic disease (L3±L4, 52.7%) and inflammatory behavior (B1±p, 87%) at diagnosis. One genotyped CYP4F3 SNP (rs2683037) not in Hardy-Weinberg Equilibrium was excluded. No associations with the remaining 4 CYP4F3 SNPs with CD were evident. However haplotype analysis revealed associations with a two-marker haplotype (TG) (rs3794987 & rs1290617) (p = 0.02; permuted p = 0.08). CYP4F2 SNPs, rs3093158 (OR (recessive) = 0.56, 95% CI = 0.35-0.89; p = 0.01), rs2074902 (OR (trend) = 1.26, 95% CI = 1.00-1.60; p = 0.05), and rs2108622 (OR (recessive) = 1.6, 95% CI = 1.00-2.57; p = 0.05) were significantly associated whereas rs1272 (OR (recessive) = 0.58, 95% CI = 0.30-1.13; p = 0.10) showed suggestions for associations with CD. A haplotype comprising these 4 SNPs was significantly associated (p = 0.007, permuted p = 0.02) with CD. Associations with SNP rs3780901 in the ALOX5 gene were borderline non-significant (OR (dominant) = 1.29, 95% CI = 0.99-1.67; p = 0.056). A haplotype comprising the 4 ALOX5 SNPs (TCAA, p = 0.036) was associated with CD, but did not withstand corrections for multiple comparisons (permuted p = 0.14).. Inherited variation in enzymes involved in the synthesis/metabolism of LTB(4) may be associated with CD. These findings implicate PUFA metabolism as a important pathway in the CD pathogenesis.

Topics: Adolescent; Adult; Canada; Case-Control Studies; Child; Child, Preschool; Crohn Disease; Fatty Acids, Unsaturated; Female; Genetic Variation; Haplotypes; Humans; Inflammation; Leukotriene B4; Male; Polymorphism, Single Nucleotide

UR-1505 is a novel pentafluoropropoxy derivative of salicylic acid, selected from a series of salicylate derivatives, according to their activity as inhibitors of T-lymphocyte activation. This study describes the anti-inflammatory activity of UR-1505 on trinitrobenzenesulphonic acid-induced colitis in rat, an experimental model that resembles to Crohn's disease (CD), as well as its in vitro effects on T-cells and bone marrow-derived macrophages (BMDM) activation. UR-1505 showed intestinal anti-inflammatory effect, associated with reduced colonic levels of TNFalpha and LTB(4), inhibition of the expression of IFNgamma and iNOS, and lower colonic leukocyte infiltration. The in vitro assays revealed that UR-1505 also inhibited T-lymphocyte proliferation and IL-12/IFNgamma production, two of the main pro-inflammatory cytokines involved in the pathogenesis of CD. However, UR-1505 did not modify LPS- nor IFNgamma-induced activation in BMDM. Thus, UR-1505 specifically affects T-cells without modifying the activation of BMDM. In conclusion, the intestinal anti-inflammatory activity of UR-1505 seems to be mediated by a reduction in the recruitment of immune cells to the inflammatory foci, together with the inhibition of T-cell activation. These results suggest that UR-1505 may be an interesting candidate to be explored for the treatment of CD.

Topics: Animals; Anti-Inflammatory Agents; Cells, Cultured; Colitis; Colon; Crohn Disease; Disease Models, Animal; Female; Glutathione; Interferon-gamma; Leukotriene B4; Macrophages; Mice; Mice, Inbred BALB C; Nitric Oxide Synthase Type II; Rats; Rats, Wistar; Salicylates; Spleen; T-Lymphocytes; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha

Previously we reported that linoleic acid (LA), but not oleic acid, caused a marked increase in the secretion of IL-8 by Crohn's human intestinal smooth muscle (HISM) cells. Antioxidants inhibited this response, implicating a role for oxidative stress and NF-kappaB, a transcription factor for IL-8 that is activated by oxidative stress. In this study, we examined two mechanisms whereby LA, the dietary precursor for arachidonic acid (AA), could increase the production of IL-8 via activation of AA pathways: 1) by generation of reactive oxygen species by the AA-pathway enzymes to activate NF-kappaB or 2) by AA metabolites. Normal and Crohn's HISM cells were exposed to LA, oxidizing solution (Ox), or oxidizing solution enriched with LA (OxLA). Exposure of cells to Ox or OxLA induced oxidative stress as determined by thiobarbituric acid reactive substances. In normal cells, Ox but not LA activated NF-kappaB as determined by transfection experiments and Western blot. In Crohn's cells, NF-kappaB was spontaneously activated and was not further activated by Ox or LA. In contrast, TNF-alpha markedly increased activation of NF-kappaB in both normal and Crohn's cells. These results indicated that LA did not increase IL-8 by activating NF-kappaB, so we evaluated the second mechanism of an effect of AA metabolites. In normal cells, OxLA, but not LA, markedly stimulated IL-8, whereas in Crohn's cells, both OxLA and LA stimulated IL-8. OxLA, also stimulated production of AA metabolites leukotriene B(4) (LTB(4)), PGE(2), and thromboxane B(2) (TXB(2)) by normal and Crohn's cells. To determine whether AA metabolites mediated the IL-8 response, cells were treated with OxLA plus indomethacin (Indo), a cyclooxygenase inhibitor, and nordihydroguaiaretic acid (NDGA), a lipoxygenase inhibitor. Both Indo and NDGA blocked the IL-8 response to OxLA. To determine more specifically a role for AA metabolites, AA was used. Similar to OxLA, OxAA stimulated production of IL-8 and AA metabolites. Pinane thromboxane, a selective thromboxane synthase inhibitor and receptor blocker, inhibited OxAA stimulation of TXB(2) and IL-8 in a dose-response manner. MK886, a selective 5-lipoxygenase inhibitor, inhibited OxAA stimulation of LTB(4) and IL-8 also in a dose-response manner. Analysis of specific gene products by RT-PCR demonstrated that HISM cells expressed receptors for both thromboxane and LTB(4). We conclude that AA metabolites mediated the IL-8 response to LA in HISM cells. Both cyclooxyge

Topics: Arachidonic Acid; Blotting, Western; Cells, Cultured; Crohn Disease; Cyclooxygenase Inhibitors; Genes, Reporter; Humans; Indomethacin; Interleukin-8; Intestinal Mucosa; Intestines; Leukotriene B4; Linoleic Acid; Luciferases; Muscle, Smooth; NF-kappa B; Oxidative Stress; Receptors, Thromboxane; RNA, Messenger

Activated neutrophils cause tissue injury in inflammatory bowel disease (IBD). Upon activation, they shed soluble Fc gamma IIIb receptors (sFc gamma RIIIb). The subsequent inflammatory response is modulated by several mediators, including neutrophil derived leukotriene B4 (LTB4), thromboxane B2 (TXB2), and prostaglandin E2 (PGE2). The aim of this study was to determine the value of gut lavage sFc gamma RIII and eicosanoid measurements for the assessment of mucosal inflammation in IBD.. A total of 18 patients with active IBD, 10 ulcerative colitis (UC), and eight Crohn's disease (CD), and 12 control patients underwent whole gut lavage. Disease activity, endoscopic appearance, and histopathology were graded. Samples were processed for the determination of sFc gamma RIIIb, LTB4, PGE2, and TXB2.. Soluble Fc gamma RIIIb concentrations were increased in both IBD groups. Significant correlations were seen between sFc gamma RIIIb and LTB4 values with histology scores. Mean eicosanoid lavage fluid concentrations in control patients were 14.1 pg/ml for LTB4, 5.6 pg/ml for PGE2, and 397 pg/ml for TXB2. Concentrations of all eicosanoids in IBD patients were significantly increased: LTB4 in UC: mean 73.2 pg/ml, in CD: 96.4 pg/ml (both p < 0.01 v controls). PGE2 in UC: 20.2 pg/ml, in CD: 43.4 pg/ml (p < 0.01). TXB2 in UC: 719.3 pg/ml, in CD: 180.6 pg/ml (both p < 0.05).. Whole gut lavage fluid analysis is an effective method to study mucosal eicosanoid production. Soluble Fc gamma RIIIb concentrations in gut lavage fluid closely correlate with histological signs of mucosal inflammation and with lavage LTB4 concentration. These data suggest that lavage Fc gamma RIIIb assessment may be used as a simple assay to estimate mucosal neutrophil infiltration in IBD.

Topics: Colitis, Ulcerative; Crohn Disease; Eicosanoids; Humans; Intestinal Mucosa; Leukotriene B4; Receptors, IgG; Therapeutic Irrigation

To investigate the leukotriene B4 (LTB4) signal transducing mechanism in polymorphonuclear neutrophils (PMNs) from patients with Crohn's disease.. Cytosolic free calcium ([Ca2+]i), inositol (1,4,5)-trisphosphate [(1,4,5)-IP3] chemotaxis, LTB4 receptor number and affinity were investigated in peripheral PMNs from 11 patients with Crohn's disease and 11 healthy controls.. There was a slight reduction (P = 0.31) in the number of LTB4 receptor sites per cell expressed on PMNs (mean Bmax 931) from nine of the 11 patients studied compared with the healthy controls (mean Bmax 1095). LTB4-mediated (1,4,5)-IP3 formation and the increase in [Ca2+]i were markedly decreased in PMNs from the 11 patients with Crohn's disease [(1,4,5)-IP3, mean +/- SEM 12 +/- 0.84 and 27.4 +/- 1.4 pmol/l/tube for patients and controls, respectively; [Ca2+]i, mean +/- SEM 295 +/- 2.75 and 598 +/- 4.7 nmol/l for patients and controls, respectively]. The decrease in calcium might be related to the decrease in Bmax (P < 0.05). Ionomycin, a calcium ionophore which bypasses the initial steps of LTB4 receptor activation, showed only a minor difference in peak [Ca2+]i between PMNs from patients and controls. LTB4-directed chemotaxis showed that the sensitivity to suboptimal concentrations of LTB4 (1.0 nmol/l) was significantly depressed in PMNs from patients (P < 0.05).. Peripheral PMNs from patients with Crohn's disease had a small deficit in the expression of LTB4 receptors. This deficiency was paralleled by marked alterations in cellular signalling. Whether these results are specific to Crohn's disease or simply result from the exposure of circulating PMNs to elevated levels of LTB4 remains to be established.

Topics: Adult; Calcium; Chemotaxis; Crohn Disease; Cytosol; Female; Humans; Inositol 1,4,5-Trisphosphate; Leukotriene B4; Male; Middle Aged; Neutrophils; Receptors, Leukotriene B4; Signal Transduction

omega-Oxidation is regarded as the major pathway for leukotriene B4 (LTB4) metabolism. Very little is known about it in colonic mucosa with inflammatory bowel disease (IBD).. We investigated the metabolic ratio of omega-oxidation to LTB4 biosynthesis in colonic mucosa from patients with IBD and control subjects. After incubation of colonic mucosa with 14C-arachidonic acid and ionophore A23187, we separated LTB4 and its omega-oxidative metabolites by high-performance liquid chromatography.. The rate of LTB4 omega-oxidation was comparable to the rate of its biosynthesis. The metabolic ratio was significantly decreased in inflamed mucosa with ulcerative colitis.. LTB4 omega-hydroxylase activity is an important factor in regulating LTB4 level in colonic mucosa, and the increased LTB4 level in inflamed mucosa with IBD, especially ulcerative colitis, is caused by decreased LTB4 omega-hydroxylase activity and increased 5-lipoxygenase activity.

Topics: Adolescent; Adult; Aged; Arachidonate 5-Lipoxygenase; Colitis, Ulcerative; Colon; Crohn Disease; Female; Humans; In Vitro Techniques; Intestinal Mucosa; Leukotriene B4; Male; Middle Aged

We investigated the therapeutic efficacy of n-3 polyunsaturated fatty acids (PUFAs) on trinitro-benzene sulfonic acid (TNBS)-induced colitis in the rats, which condition is considered an experimental Crohn's disease (CD). In rats with TNBS-induced colitis, feeding with an elemental diet (ED) plus 2% n-3 PUEA-rich perilla oil significantly suppressed plasma leukotriene (LT) B4 and ulcer index compared to that in rats fed with ED plus 2% n-6 PUFA-rich safflower oil (34.2 +/- 12.3 s 63.8 +/- 13.2 pg/ml and 8.8 +/- 12.1 vs 66.4 +/- 33.1, P < 0.01, respectively). Moreover, the plasma LTB4 and the ulcer index were significantly correlated (P < 0.05). Feeding with ED plus 2% alpha-linolenic acid (A-LA)-rich vegetable oil significantly reduced plasma LTB4 and colonic weight compared to that in rats fed with ED plus 2% eicosapentaenoic acid (EPA)/docosahexaenonic acid (DHA)-rich fish oil in this model (61.6 +/- 10.5 vs 85.0 +/- 20.9 pg/ml and 0.83 +/- 0.13 vs 0.96 +/- 0.08g, P < 0.05, respectively). This study suggested that dietary fat manipulation with perilla oil can reduce colonic damage and that this is correlated with the suppression of plasma LTB4. The therapeutic efficacy of A-LA in controlling intestinal inflammation in experimental CD may be superior to that of EPA and DHA.

Topics: alpha-Linolenic Acid; Animals; Colitis; Colon; Crohn Disease; Fatty Acids, Omega-3; Fish Oils; Food, Formulated; Leukotriene B4; Male; Organ Size; Rats; Rats, Sprague-Dawley; Safflower Oil; Trinitrobenzenesulfonic Acid

We considered the role of two neutrophil chemotactic agents (interleukin-8 and leukotriene B4) and of myeloperoxidase (a neutrophil-associated enzyme) in the pathologic condition of Crohn's disease (CD). Serial biopsy samples were taken at different sites in the colon, washed in 0.02 M phosphate-saline buffer, homogenized, and then sonicated. Interleukin-8 levels were significantly increased throughout the colonic mucosa (> 300 pg/mg protein) in patients with CD compared with control groups (< 40 pg/mg protein) (p < or = 0.01). A two- to six-fold increase in leukotriene B4 was also found in CD, whereas mucosal levels of myeloperoxidase were unchanged compared with control subjects. This study demonstrates that interleukin-8 and leukotriene B4 may have an immunologic role in the pathologic condition of CD.

Topics: Adult; Aged; Chromatography, High Pressure Liquid; Colon; Crohn Disease; Humans; Interleukin-8; Intestinal Mucosa; Leukotriene B4; Middle Aged; Peroxidase; Radioimmunoassay

omega-oxidation is regarded as the major pathway for the catabolism of leukotriene B4 (LTB4). To determine how LTB4 omega-hydroxylase is modulated in inflammatory bowel disease, we investigated the kinetic characteristics of this enzyme in 10 patients with Crohn's disease (CD), nine with ulcerative colitis (UC) and eight healthy control subjects. After incubating polymorphonuclear leukocytes with various concentrations of 3H-labeled LTB4, omega-oxidation products were separated by high performance liquid chromatography (HPLC) and the radioactivity was measured by a liquid scintillation counter. The apparent Vmax values were significantly higher in both disease than in healthy control subjects, although the difference between CD and UC was insignificant. There was no difference in the apparent Km values. And the Vmax/Km ratios of patients with CD were significantly higher than that of healthy control subjects. It is suggested that LTB4 metabolism is activated in inflammatory bowel disease (IBD) and that the modulation of this enzyme activity has an important role in the pathogenesis of inflammatory bowel disease.

Topics: Adolescent; Adult; Arachidonic Acid; Colitis, Ulcerative; Crohn Disease; Cytochrome P-450 Enzyme System; Cytochrome P450 Family 4; Female; Humans; Leukotriene B4; Male; Middle Aged; Mixed Function Oxygenases; Neutrophils

The in vitro synthesis of leukotriene B4 (LTB4) was evaluated in colorectal biopsy specimens and resection tissue from patients with inflammatory bowel disease. The in vitro formation of LTB4 from biopsy tissues stimulated with calcium ionophore A23187 correlated with the degree of mucosal inflammation assessed at sigmoidoscopy, and with neutrophil infiltration measured as myeloperoxidase activity. Biopsy specimens from patients taking prednisolone formed less LTB4 than those from patients not on prednisolone, with comparable levels of inflammation seen at sigmoidoscopy. The formation of LTB4 was reduced dose-dependently by the acetohydroxamic acid 5-lipoxygenase inhibitor BWA4C, with no significant inhibition of prostaglandin E2 or thromboxane B2 synthesis. In inflamed colonic resection tissue from colitic patients, the IC50 for inhibition of LTB4 formation by BWA4C was 0.03 mumol/l, compared with an IC50 of 0.8 mumol/l for NDGA. Thus, BWA4C is a potent and selective inhibitor of LTB4 synthesis in colonic tissue from patients with ulcerative colitis. Acetohydroxamic acid 5-lipoxygenase inhibitors, exemplified by BWA4C, may be useful to evaluate the clinical importance of LTB4 in ulcerative colitis, and offer a novel therapy for the disease.

Topics: Benzeneacetamides; Colitis, Ulcerative; Colon; Crohn Disease; Culture Techniques; Dose-Response Relationship, Drug; Humans; Hydroxamic Acids; Leukotriene B4; Lipoxygenase Inhibitors; Rectum

Ten patients with active Crohn's disease who have been managed with parenteral-nutrition therapy were administered a lipid emulsion either with [containing 0.6 g eicosapentaenoic acid (EPA)] or without fish oil for 2 wk. We isolated polymorphonuclear leukocytes (PMNLs) from the patients before and after this treatment and measured the amounts of leukotriene B4 (LTB4) and leukotriene B5 (LTB5) generated by activated PMNLs by reversed-phase HPLC. The LTB5 generation in active Crohn's disease before this treatment was significantly lower than in healthy control subjects. The amount of LTB5 and the LTB5-LTB4 ratio increased significantly after fish-oil supplementation. The difference with LTB4 was not statistically significant. We have shown that daily intravenous administration of 0.6 g EPA influenced the generation of leukotrienes in active Crohn's disease even after short-term treatment. Further investigations are necessary to clarify the correlation between EPA and clinical improvement in Crohn's disease.

Topics: Adult; Crohn Disease; Eicosapentaenoic Acid; Fat Emulsions, Intravenous; Female; Fish Oils; Humans; Infusions, Intravenous; Leukotriene B4; Leukotrienes; Male; Neutrophils

Interleukin 1 beta in biopsy specimens from inflamed colonic mucosa of patients with active inflammatory bowel disease was studied. Compared with normal colonic mucosal biopsy specimens, a significantly greater amount of interleukin 1 beta was present in rectal mucosa before (median (range) 4.3 (2.0-11.8) v 119.2 (30.1-286.8) pg/mg; p less than 0.01) and produced during organ culture (39.1 (9.4-106.8) v 97.6 (28.2-991.6) pg/mg; p less than 0.01). Values of interleukin 1 beta after culture correlated with concentrations of thromboxane B2. Organ culture of inflamed biopsy specimens in the presence of 5 aminosalicylic acid and dexamethasone reduced the amount of interleukin 1 beta detected. At the doses studied, 5 aminosalicylic acid also reduced the amount of leukotriene B4 detected after culture.

Topics: Adult; Aged; Aged, 80 and over; Aminosalicylic Acids; Colitis, Ulcerative; Colon; Crohn Disease; Dexamethasone; Female; Humans; Inflammatory Bowel Diseases; Interleukin-1; Leukotriene B4; Male; Mesalamine; Middle Aged; Organ Culture Techniques; Sulfapyridine; Thromboxane B2

Eicosanoids are modulators of defensive and inflammatory processes in the gut mucosa, and may be involved in the pathogenesis of chronic inflammatory lesions of the bowel. As omega-3 fatty acids compete with the omega-6 as precursors of eicosanoid synthesis, we compared the effects of dietary supplementation with either sunflower (source of omega-6) or cod liver (source of omega-3) oil on the development of chronic granulomatous lesions in the rat colon. After four weeks on the supplemented diets, plasma omega-6 fatty acid content was significantly higher in the sunflower group, while omega-3 fatty acids predominated in the cod liver group. Inflammatory colitis was then induced by intracolonic administration of trinitrobenzene sulphonic acid. Luminal eicosanoid release, as measured by radioimmunoassay of intracolonic dialysis fluid, increased significantly after the challenge in both groups. Generation of prostaglandin E2 (PGE2) and leucotriene B4 (LTB4) peaked by day 3 and thereafter declined; thromboxane B2 (TXB2), instead, continued to increase from day 3 to 20 in sunflower fed rats, whereas this change was blunted in cod liver animals. The rats were killed 20, 30, or 50 days after the induction of colitis, and the colonic lesions were scored macroscopically (adhesions to surrounding tissues, strictures, ulcerations, and wall thickness) and histologically (ulceration, inflammation, depth of the lesions, and fibrosis). In cod liver animals, the damage score was markedly reduced by day 30, and inflammation and ulceration were almost absent by day 50. In conclusion, a fish oil diet prevents the increase in thromboxane in the chronic state of inflammation and shortens the course of the colonic disease by diminishing both the severity of the lesions and their progression to chronicity.

Topics: Animals; Body Weight; Cod Liver Oil; Crohn Disease; Dietary Fats; Dinoprostone; Fatty Acids; Fatty Acids, Omega-3; Fish Oils; Helianthus; Leukotriene B4; Male; Plant Oils; Rats; Rats, Inbred Strains; Thromboxane B2; Trinitrobenzenesulfonic Acid

Topics: Blood Platelets; Crohn Disease; Dietary Fats, Unsaturated; Epoprostenol; Erythrocyte Membrane; Fish Oils; Humans; Hydroxyeicosatetraenoic Acids; Iloprost; Leukotriene B4; Membrane Lipids; Neutrophils; Platelet Aggregation

To compare the local release of arachidonic acid metabolites in inflammatory diarrheal disease, in vivo equilibrium dialysis of the rectum was done in consecutive untreated patients with ulcerative colitis (n = 20), Crohn's colitis (n = 10), and Clostridium difficile colitis (n = 7). All patients had endoscopically proven rectal inflammation. Eicosanoid profiles were determined in rectal dialysates by radioimmunoassay after preliminary purification. Concentrations of prostaglandin E2, prostaglandin F2 alpha, and thromboxane B2, but not 6-keto-prostaglandin F1 alpha, were raised in all groups and compared with healthy controls. The highest levels within each group were obtained in patients with widespread epithelial damage, as judged by endoscopy. In patients with ulcerative colitis, an extreme rise in prostaglandin E2 and thromboxane B2 were observed. Similarly, concentrations of leukotriene B4 were substantially increased in ulcerative colitis, but in Crohn's colitis and Clostridium difficile colitis only those patients with rectal ulcerations showed elevations. These findings probably reflect more severe tissue damages in ulcerative colitis, but differences between disease groups in cell-to-cell interaction may also contribute. The data suggest, therefore, that therapeutic inhibition of lipoxygenase pathways may prove more effective in ulcerative colitis than in Crohn's disease.

Topics: Adolescent; Adult; Aged; Arachidonic Acid; Arachidonic Acids; Colitis; Colitis, Ulcerative; Crohn Disease; Dialysis; Dinoprost; Dinoprostone; Eicosanoic Acids; Enterocolitis, Pseudomembranous; Female; Humans; Leukotriene B4; Male; Middle Aged; Prostaglandins E; Prostaglandins F; Rectum; Thromboxane B2

Serum interferon (IFN) of alpha-class was studied in 64 consecutive patients, 26 with Crohn's disease, 38 with ulcerative colitis, and in 34 healthy volunteers. Detectable IFN-alpha in 10 patients was associated with a moderate to severe activity of chronic inflammatory bowel disease (CIBD). However, 19 of 28 patients (68%) with activity in their disease did not have elevated IFN-alpha levels. The three groups, ulcerative colitis, Crohn's disease, and healthy volunteers did not reveal any statistically significant difference in serum IFN-alpha, as four of 34 healthy controls without intercurrent infections had elevated levels as well. Possible effects of alpha, beta, and gamma classes of IFN on endogenous arachidonic acid (AA) release and metabolism in human neutrophils was investigated in a substudy. IFN-alpha caused a dose-dependent release of AA from phospholipids and metabolism of a modest fraction of leukotriene B4 (LTB4) and 5-hydroxyeicosatetraenoic acid (5-HETE) at doses reaching a maximum of 100 IU/ml. IFN of the beta and gamma classes did not exert such effects. Addition of complement 5a to cells activated by IFN-alpha caused induction of increased 5-lipoxygenase activity with unchanged release of AA. As only 16% of all CIBD patients had elevated IFN-alpha levels as compared to 12% among the group of healthy volunteers, IFN-alpha does not seem to be of importance for the perpetuation of the inflammatory reaction in ulcerative colitis or Crohn's disease, and other factors may therefore be responsible for activation of the inflammatory cells to production of LTB4 and 5-HETE.

Topics: Adult; Aged; Aged, 80 and over; Arachidonic Acids; Colitis, Ulcerative; Crohn Disease; Female; Humans; In Vitro Techniques; Interferon Type I; Interferon-gamma; Leukotriene B4; Male; Middle Aged; Neutrophils

To examine pharmacokinetics and tolerance of long term administration of olsalazine (azodisalicylate), increasing doses of the drug were given for one year to 31 patients with ulcerative colitis (UC) and nine patients with Crohn's colitis (CC), refractory to, or intolerant of sulphasalazine, until sustained remission was obtained or a maximum of 4 g/day was reached. Colonic drug metabolism was studied by equilibrium in vivo dialysis of faeces. Complete azoreduction occurred in most cases. Concentrations of 5-aminosalicylic acid, but not N-acetyl-5-aminosalicylic acid, in faecal dialysates increased dose dependently. Serum concentrations disclosed no cumulation in the long term and olsalazine was well tolerated, although loose stools occurred transiently in some patients with extensive disease: this was associated with a larger proportion of unsplit olsalazine in the faecal dialysates. Patients with ulcerative colitis having a high prostaglandin E2 concentration (greater than ng/ml) determined by equilibrium dialysis of rectum, were less likely to benefit from treatment. Olsalazine is a very effective means of delivery of 5-aminosalicylic acid to the colonic mucosa in active disease. Use of the drug in controlled trials may be considered safe even in prolonged high dosage.

Topics: Adolescent; Adult; Aged; Aminosalicylic Acids; Colitis, Ulcerative; Crohn Disease; Dinoprostone; Feces; Female; Humans; Leukotriene B4; Male; Mesalamine; Middle Aged; Prostaglandins E; Rectum

THIS CASE REPORT DESCRIBES clinical and laboratory findings for a 60-year-old woman with recently diagnosed Crohn's disease and severe generalized periodontitis. Comparison of dental radiographs taken in 1975, in 1983, and at the time of our evaluation in 1986 revealed dramatic progression of alveolar bone loss over that period. Standard laboratory blood tests did not reveal any remarkable significant leukocyte abnormalities, but flow cytometric analysis of lymphocytes revealed a paucity of B cells stained with anti-light chain antibodies, and an increased proportion of T lymphocytes which were dully-stained with anti-CD5 monoclonal antibody. B cell function as determined by in vitro proliferative responsiveness to anti-IgM antibody was only about 50% of that observed with cells from two healthy normal subjects. Serum leukotriene B4 (LTB4) was elevated to 150% of normal values, in spite of the fact that the patient was taking a systemic anti-inflammatory drug which is known to reduce LTB4 levels. The microbial flora was highly mixed and included several putative periodontopathic bacteria. Therapy consisted of oral hygiene instruction, scaling and root planing, mucoperiosteal-flap curettage, extracoronal splinting, and selective extraction of three teeth. The periodontal status improved markedly with therapy. Possible relationships between the patient's immunological status, her Crohn's disease, and the severe periodontal breakdown are discussed.

Topics: B-Lymphocytes; Crohn Disease; Female; Humans; Leukotriene B4; Lymphocytes; Middle Aged; Neutrophils; Periodontitis

Topics: Colon; Crohn Disease; Dinoprostone; Humans; Intestinal Mucosa; Leukotriene B4; Peptides; Prostaglandins E; Reference Values

Circulating neutrophils were investigated in 15 patients with Crohn's disease (CD), 15 with ulcerative colitis (UC), and 15 healthy volunteers. Dose-response curves for chemotaxis in Boyden chambers were analysed for sensitivity to leukotriene B4 (LTB4), its 20-hydroxy-LTB4 (20-OH-LTB4) and 20-carboxy-LTB4 (20-COOH-LTB4) catabolites, and 5- and 15-hydroxyeicosatetraenoic acids (HETEs). Positive controls included: complement 5a (C5a), formy-L-methionyl-L-leucyl-L-phenylalanine (f-Met-Leu-Phe), and casein. Control chemotaxis test were performed at concentrations yielding optimal responses in leucocytes of healthy volunteers. Chemotaxis to suboptimal concentrations of LTB4 1.0 and 3.2 nmol/l, and 5-HETE 316 nmol/l, was markedly depressed in patients with chronic inflammatory bowel disease (CIBD). Analyses of individual dose-response curves revealed an underlying decreased sensitivity to LTB4 in 11 out of 30 patients, to 5-HETE in 10 out of 30 patients with a corresponding decrease of median sensitivity to LTB4 and 5-HETE in both CD and UC. Peak responses to LTB4, 5-HETE, f-Met-Leu-Phe, and casein were identical in the three groups tested, whereas the C5a values were significantly depressed in both groups of patients (p less than 0.05). The potency of LTB4 exceeded that of 5-HETE by a factor of approximately 100 whereas 20-OH-LTB4 was nearly as potent as LTB4. 20-COOH-LTB4 and 15-HETE did not activate chemotaxis of human neutrophils. These findings are suggestive of a competitive inhibition of receptors with heterogeneity for LTB4 and 5-HETE.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Chemotaxis, Leukocyte; Colitis, Ulcerative; Crohn Disease; Dose-Response Relationship, Drug; Hydroxyeicosatetraenoic Acids; Leukotriene B4; Neutrophils; Receptor, Anaphylatoxin C5a; Receptors, Complement

An important histologic feature of inflammatory bowel disease (IBD) is infiltration of the colonic mucosa with neutrophils. To investigate the nature of the chemotactic agents responsible for this infiltration, colonic mucosa from three normals and nine patients with inflammatory bowel disease (seven ulcerative colitis, two Crohn's colitis) was assayed for chemotactic activity for human neutrophils in vitro in a Boyden chamber. There was more (greater than 10-fold more) chemotactic activity in homogenates of inflammatory bowel disease mucosa than in homogenates of normal colonic mucosa. Analysis of the chemotactic activity in the inflammatory bowel disease mucosa revealed that most was lipid extractable. Moreover, when the lipid extract was fractionated by reverse-phase high-pressure liquid chromatography, the only fraction with significant chemotactic activity was the fraction that coeluted with leukotriene B4. The chemotactic response to IBD mucosa was blocked by anti-LTB4 antisera. The amount of chemotactic activity in lipid extracts of different inflammatory bowel disease specimens correlated well with the concentration of leukotriene B4 measured by UV absorbance (250 ng/g of mucosa). These data suggest that leukotriene B4 is an important stimulus to neutrophil chemotaxis in inflammatory bowel disease and, thus, may play a major role in the amplification of the inflammatory response in this condition.

Topics: Adult; Chemotactic Factors; Chemotaxis, Leukocyte; Chromatography, High Pressure Liquid; Colitis, Ulcerative; Crohn Disease; Female; Humans; Intestinal Mucosa; Leukotriene B4; Male; Middle Aged; Neutrophils

Topics: Aminosalicylic Acids; Colon; Crohn Disease; Dinoprostone; Humans; In Vitro Techniques; Intestinal Mucosa; Leukotriene B4; Mesalamine; Peptide Biosynthesis; Prostaglandins E; Sulfasalazine

Despite the extensive use of sulfasalazine (SAS) and/or 5-aminosalicylic acid (5-ASA) in patients with inflammatory bowel disease and, more recently, rheumatoid arthritis, their mode of action has not been elucidated so far. None of the numerous pharmacological and biochemical effects described, including immunosuppressive, antifolate, and modulatory actions on lymphocyte and leukocyte functions, could be defined unequivocally as mediating their beneficial activity. Recently, interest has focused on actions of SAS and 5-ASA on the various enzymes of the arachidonic acid cascade. Mucosa of patients with inflammatory bowel disease generates excessive amounts of cyclooxygenase products such as prostaglandins (PG) as well as 5-lipoxygenase products such as leukotriene (LT) B4 and sulfidopeptide-LT. Both PG and LT exert proinflammatory actions and are potentially important mediators of mucosal inflammation. SAS and 5-ASA, however, have been found to inhibit PG synthesis under certain experimental conditions only, while increasing PG formation under other conditions. While SAS was found to inhibit colonic LTB4 synthesis, 5-ASA was reported to selectively affect the cyclooxygenase pathway of arachidonate metabolism in this tissue. Our results demonstrate that, like the parent compound, the metabolite 5-ASA in a dose-dependent manner inhibits release of LTB4 and sulfidopeptide-LT from normal human colonic mucosa (IC50 3.5 and 3.7 mmol/liter, respectively). Indomethacin, which has no efficacy in the treatment of patients with inflammatory bowel disease, on the other hand, selectively inhibited PGE2 formation in normal and inflamed colonic mucosa (IC50 1.7 and 1.0 mmol/liter, respectively) without reducing synthesis of LTB4 or sulfidopeptide-LT.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Aminosalicylic Acids; Arachidonic Acid; Arachidonic Acids; Arthritis, Rheumatoid; Colitis, Ulcerative; Crohn Disease; Dose-Response Relationship, Drug; Humans; In Vitro Techniques; Intestinal Mucosa; Leukotriene B4; Leukotriene E4; Mesalamine; Rectum; SRS-A; Sulfasalazine

The metabolism of endogenous arachidonic acid P(AA) was investigated in activated neutrophils from 20 patients with Crohn's disease, 20 with ulcerative colitis, and 25 healthy volunteers. 1-14C-P(AA) was incorporated into intracellular pools of phospholipids prior to activation of the cells with ionophore A23187 and analyses of released arachidonic acid metabolites by thin layer chromatography. Total release of radioactivity expressing the release of arachidonic acid and its metabolites, was equal in the experimental and control groups, which suggests a normal substrate availability. In contrast, there was a marked increase in the relative release of leucotriene B4 (LTB4) and its omega-oxidation products, 20-hydroxy-LTB4 (20-OH-LTB4) and 20-carboxy-LTB4 (20-COOH-LTB4), with LTB4 values exceeding the reference interval in seven of 20 patients with Crohn's disease, median 8.7%, and in six of 20 patients with ulcerative colitis, median 7.7%, as compared with a median of 5.3% in healthy volunteers. Furthermore, a decreased release of unmetabolised arachidonic acid, correlating inversely with the release of LTB4 in all experimental and control groups, and normal values for the production of other metabolites of arachidonic acid--for example, 5-hydroxyeicosatetraenoic acid (5-HETE) and 12-hydroxyheptadecatrienoic acid (HHT), point to an enzymatic abnormality such as increased activity of leucotriene B synthetase. An increased capacity for release of LTB4, the major pro-inflammatory metabolite of arachidonic acid lipoxygenation by polymorphonuclear leucocytes, may contribute to perpetuation of the inflammation and to tissue destruction in chronic inflammatory bowel disease. Our findings agree with previous reports of an increased release of LTB4 by the colonic mucosa in this condition.

Topics: Adolescent; Adult; Arachidonic Acid; Arachidonic Acids; Calcimycin; Colitis, Ulcerative; Crohn Disease; Female; Humans; Hydroxyeicosatetraenoic Acids; Leukotriene B4; Male; Middle Aged; Neutrophils

Tissues of the gastrointestinal tract synthesize leukotriene (LT) B4 and the sulfidopeptide-leukotrienes LTC4, LTD4 and LTE4 from endogenous substrate. Formation of leukotrienes was demonstrated using radioimmunoassay, high pressure liquid chromatography (HPLC) and bioassay. Under basal conditions the gastrointestinal tissues released minor amounts of leukotrienes only. Formation of lipoxygenase-derived products of arachidonic acid metabolism was, however, significantly increased in the presence of various stimuli. Thus, significant amounts of LTB4 and of sulfidopeptide-leukotrienes were released from colonic and gastric mucosa of guinea-pigs sensitized against ovalbumin when incubations were carried out in the presence of antigen. Antigen-induced leukotriene formation was not found in the muscularis propria and subserosal of ovalbumin-sensitized guinea-pigs. Release of cyclooxygenase-derived metabolites of arachidonic acid, on the other hand, was most abundant in the subserosal layer of the guinea-pig colon and was not influenced by the immunological reaction. Inhibitors of cyclooxygenase, such as indomethacin, reduced gastrointestinal formation of prostaglandins, but not of leukotrienes. Inhibitors of 5-lipoxygenase, however, significantly decreased leukotriene formation. Synthesis of LTB4 and of sulfidopeptide-leukotrienes was also found in human colonic mucosal tissue, using the divalent cation-ionophore A23187 as stimulating agent. HPLC analysis demonstrated that the sulfidopeptide-leukotrienes released were composed of a mixture of LTC4, LTD4 and LTE4. In addition, human colonic mucosal tissue contained high activities of enzymes that rapidly convert LTC4 to LTE4. As in most biological systems LTE4 is less active than LTC4 and LTD4 degrading enzymes might represent a local inactivating mechanism. Mucosal tissue of patients with Crohn's disease synthesized considerably more LTB4 and sulfidopeptide-leukotrienes than non-inflamed mucosa.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Animals; Arachidonate Lipoxygenases; Arachidonic Acid; Arachidonic Acids; Calcimycin; Chromatography, High Pressure Liquid; Colon; Crohn Disease; Cyclooxygenase Inhibitors; Dinoprostone; Guinea Pigs; Humans; Indomethacin; Intestinal Mucosa; Leukotriene B4; Lipoxygenase Inhibitors; Prostaglandins E; SRS-A

The capacity of peripheral neutrophils for activation of the arachidonic acid (AA) metabolism was studied during phagocytosis of IgG containing immune complexes (ICs) binding to Fc-receptors. Release of approximately 9% of the intracellular pool of radiolabelled AA in phospholipids, and release of the pro-inflammatory mediators, leukotriene B4 (LTB4), constituting 1.8%, and 5-hydroxyeicosatetraenoic acid (5-HETE), constituting 2.9% of the total radioactivity released, were demonstrated in 15 patients with untreated Crohn's disease, 15 patients with ulcerative colitis, and in 15 healthy volunteers. The concentrations of LTB4 and 5-HETE released were within the range of chemotactic activity for the two lipoxygenase products. Multiple large IgG containing ICs were revealed in neutrophils after phagocytosis by immunofluorescence. A minor defect in the IC uptake in patients with Crohn's disease observed in the absence of complement only, did not result in a subnormal activation of arachidonic acid release or metabolism. The study suggests that complexes of the IgG-class previously demonstrated in chronic inflammatory bowel disease, particularly in Crohn's disease, may activate inflammatory neutrophils leading to release of significant amounts of the pro-inflammatory lipoxygenase metabolites, LTB4 and 5-HETE.

Topics: Adult; Aged; Antigen-Antibody Complex; Colitis, Ulcerative; Crohn Disease; Female; Humans; Hydroxyeicosatetraenoic Acids; Leukotriene B4; Male; Middle Aged; Neutrophils; Phagocytosis

Topics: Animals; Cells, Cultured; Colitis, Ulcerative; Crohn Disease; Humans; Interleukin-2; Leukotriene B4; Mice; Mice, Nude; Neutrophils; T-Lymphocytes, Regulatory

Leukotriene B4, an arachidonic acid metabolite, is a potent chemotactic agent, and is thought to be an important mediator of inflammation. To investigate the role of this compound as a mediator of inflammation in inflammatory bowel disease, arachidonic acid was incubated with ionophore and colonic mucosa from patients with inflammatory bowel disease and from normal subjects. Mucosa from patients with inflammatory bowel disease converted 2.17% of exogenous arachidonate to leukotriene B4; mucosa from normal subjects converted 0.37%. The production of leukotriene was blocked by sulfasalazine. To determine if inflammatory bowel mucosa contained endogenous leukotriene B4, lipid extracts were analyzed by high pressure liquid chromatography. Mucosa from patients with inflammatory bowel disease contained 254 ng of leukotriene B4 per gram and mucosa from normal subjects contained less than 5 ng of leukotriene B4 per gram. The presence of significant amounts of leukotriene B4 in colonic mucosa in patients with inflammatory bowel disease, combined with the known biologic effects of leukotriene B4, suggests that it may be an important mediator of inflammation in inflammatory bowel disease.

Topics: Adolescent; Adult; Arachidonic Acid; Arachidonic Acids; Chromatography, High Pressure Liquid; Chromatography, Thin Layer; Colitis, Ulcerative; Colon; Crohn Disease; Female; Gas Chromatography-Mass Spectrometry; Humans; In Vitro Techniques; Intestinal Mucosa; Leukotriene B4; Male; Middle Aged