leukotriene-b4 and Kidney-Failure--Chronic

To investigate the effect of supplementation with different sources of oils rich in long chain fatty acids, ie, fish oil (FO) and safflower oil (SO), on the production of leukotriene B4 (LTB4) by polymorphonuclear leukocytes (PMNLs) in hemodialysis patients and the consequent effects on the symptoms of pruritus.. Randomized, prospective, double-blind study for 2 treatment groups.. Three Medical Center-affiliated units.. Twenty-two patients on maintenance hemodialysis, of both sexes, age > or = 20 years with complaint of dry and/or itchy skin.. Two groups of patients receiving daily supplements of 6 g ethyl ester of FO or SO for 16 weeks.. Red blood cell (RBC) fatty acid profile, LTB 4 production by PMNLs, and pruritus symptoms at baseline and after supplementation.. After supplementation, the FO group had a higher RBC 22:6n3, total n-3 fatty acids, and ratio of total n-3 to total n-6 fatty acids (P < .05) than the SO group. The change in LTB4 production (pg/mL) from baseline to week 16 was 240.7 +/- 200.2 to 29.2 +/- 14.6 in the FO group and from 171.1 +/- 121.7 to 31.9 +/- 14.7 in the SO group. The overall pruritus score change was 16.7 +/- 11.4 to 8.9 +/- 9.2 in the FO group and from 17.5 +/- 8.8 to 13.1 +/- 5.6 in the SO group. FO supplementation did not result in a significant specific effect on LTB4 production by the PMNLs. There was a nonsignificant decrease in the pruritus scores that could be clinically significant and important to patients suffering with this condition.. Supplementation with FO results in significant incorporation of n-3 fatty acids in the RBCs. Intervention with both FO and SO resulted in a nonsignificant improvement of clinical symptoms of pruritus and a nonsignificant reduction in LTB 4 production by PMNLs in the hemodialysis patients. The percent decrease in total puritus score was greater for the FO group compared with the SO group.

Topics: Adult; Aged; alpha-Tocopherol; Arachidonate 5-Lipoxygenase; Dietary Fats, Unsaturated; Double-Blind Method; Erythrocytes; Fatty Acids, Omega-3; Fatty Acids, Omega-6; Female; Fish Oils; gamma-Tocopherol; Humans; Kidney Failure, Chronic; Leukotriene B4; Male; Middle Aged; Neutrophils; Prospective Studies; Pruritus; Renal Dialysis; Safflower Oil; Surveys and Questionnaires

Topics: Dietary Fats, Unsaturated; Dietary Supplements; Eicosapentaenoic Acid; Fatty Acids, Omega-3; Female; Humans; Kidney Failure, Chronic; Leukotriene B4; Leukotrienes; Male; Middle Aged; Neutrophils; Olive Oil; Plant Oils; Reference Values; Renal Dialysis

Leukotriene B4 (LTB4) plays an important role in acute and chronic inflammatory and hypersensitive reactions. We studied the time course of LTB4 biosynthesis in whole blood in 18 patients with end-stage renal failure maintained on regular hemodialysis with two different membranes, cuprophane and polyacrylonitrile (AN 69). The basal levels of LTB4 from dialysis patients did not differ significantly from a normal control group. Compared to predialytic values, the cuprophane membrane caused a maximal release of LTB4 by a factor of about 4.5 (p less than 0.01) within the first 10 to 20 minutes. Thereafter the level fell and returned to baseline range at the end of the hemodialysis session. With the use of the AN 69 membrane no significant increase of LTB4 could be demonstrated. The changes in LTB4 concentration showed a close temporal correlation to the alterations in white blood cell count. We conclude that (1) LTB4 is a biologically important mediator of neutrophil activation during hemodialysis, and (2) LTB4 may be a sensitive marker of biocompatibility in vivo.

Topics: Acrylic Resins; Biocompatible Materials; Cellulose; Female; Humans; Kidney Failure, Chronic; Kidneys, Artificial; Leukopenia; Leukotriene B4; Male; Membranes, Artificial

Cuprophane membranes elict intense blood-surface interactions during clinical hemodialysis. The goal of the present studies was to determine whether calcium channel blockade may alter hemodialysis-related leukotriene B4 (LTB4) generation and neutropenia in 12 patients with end-stage renal failure. The patients were randomized to receive either placebo or nitrendipine for six weeks. Compared with untreated patients, the calcium channel blocker treatment group had significantly lower predialysis plasma LTB4 levels, Nitrendipine reduced both the magnitude of LTB4 generation and of neutropenia during the early phase of hemodialysis, but did not alter the close temporal relation of LTB4 accumulation and neutrophil activation. Therefore, the generation and release of LTB4 by neutrophils may be a calcium-dependent event. Furthermore, these results suggest that activation of neutrophil 5-lipoxygenase may contribute to the alterations in neutrophils of hemodialysis patients.

Topics: Aged; Aprotinin; Cellulose; Female; Humans; Kidney Failure, Chronic; Leukotriene B4; Male; Membranes, Artificial; Middle Aged; Neutropenia; Nitrendipine; Radioimmunoassay; Renal Dialysis

Reactive oxygen species formation and release of pro-inflammatory/pro-atherogenic cytokines, that is, interleukin 1-beta and tumor necrosis factor-alpha, need the activation of the arachidonic acid cascade via the enzyme 5-lipoxygenase (5-Lox). 5-Lox activity and expression are significantly increased in peripheral blood mononuclear cells (PBMCs) of end-stage renal disease (ESRD) patients on maintenance hemodialysis (HD). Diets enriched with n-3 polyunsaturated fatty acids (PUFAs) (omega-3) have been associated to a lower incidence of coronary heart disease (CHD) and a reduction in atherosclerotic lesions. Omega-3 may interfere with the arachidonic acid cascade by inhibiting 5-Lox. Lipid peroxidation, leukotriene B(4) (LTB(4)) production, 5-Lox activity and expression were investigated in PBMC isolated from ESRD patients under maintenance HD before and after a 3-month oral supplementation with omega-3 at a daily dose of 2700 mg of n-3 PUFAs at the average eicosapentaenoic acid/docosaesaenoic acid ratio of 1.2 and finally after a further 3-month washout with no omega-3 supplementation. PBMCs from non-uremic volunteers were also investigated for comparison to normal parameters. Administration of omega-3 reduced significantly lipid peroxidation (P < 0.0001), LTB(4) synthesis (P < 0.0001) and 5-Lox activity (P < 0.0001), with no effect on 5-Lox protein expression. After the 3-month washout, all parameters were comparable to those observed before treatment. Our results resemble those obtained after oral administration of vitamin E and are consistent with a reversible, dose-dependent inhibition of 5-Lox by omega-3. Upregulation of 5-Lox may also be related to the increased mitochondrial damage and apoptosis of PBMCs observed in ESRD patients compared to non-uremic controls. Omega-3 may thus protect PBMCs of ESRD patients against oxidative stress.

Topics: Aged; Apoptosis; Arachidonate 5-Lipoxygenase; Case-Control Studies; Fatty Acids, Omega-3; Gene Expression; Humans; Kidney Failure, Chronic; Leukocytes, Mononuclear; Leukotriene B4; Lipid Peroxidation; Lipoxygenase Inhibitors; Middle Aged; Oxidative Stress; Renal Dialysis

Lipid peroxidation and oxidative stress are enhanced in peripheral blood mononuclear cells (PBMCs) from hemodialysis (HD) patients because of upregulation of the 5-lipoxygenase pathway of the arachidonate cascade. 5-Lipoxygenase activity is specifically inhibited by vitamin E both in vitro and in vivo regardless of its administration route.. The effect of arachidonate cascade enzymes and vitamin E on oxidative stress and apoptosis was investigated in PBMCs from 16 maintenance HD patients treated for at least 6 months with cuprammonium rayon membranes in a two-step crossover study: after a 4-week treatment with vitamin E-coated cuprammonium rayon membranes and again after a 4-week treatment with oral vitamin E. Control PBMCs were obtained from 16 healthy volunteers.. Membrane lipoperoxidation, cellular luminescence, membrane fluidity, and leukotriene B(4) content were significantly greater in PBMCs from HD patients; lipoxygenase was upregulated, but prostaglandin H synthase (PHS) was not affected. Regardless of administration route, vitamin E partially controlled lipid peroxidation and oxidative stress through direct inhibition of 5-lipoxygenase. Cultured PBMCs from HD patients showed a significant increase in apoptotic cells compared with controls. Vitamin E markedly reduced cell luminescence, membrane fluidity, and apoptosis, whereas the PHS inhibitor indomethacin was ineffective. Similar results were obtained with control PBMCs induced to apoptosis by hydrogen peroxide.. Reported data suggest that the 5-lipoxygenase branch of the arachidonate cascade is only responsible for membrane peroxidation, oxidative stress, and apoptosis of PBMCs of HD patients, and administration of vitamin E may be helpful in the control of oxidative stress-related disease in these subjects.

Topics: Apoptosis; Arachidonate 5-Lipoxygenase; Arachidonic Acid; Cells, Cultured; Cellulose; Cross-Over Studies; Drug Administration Routes; Humans; Kidney Failure, Chronic; Leukocytes, Mononuclear; Leukotriene B4; Lipid Peroxidation; Luminescent Measurements; Membrane Fluidity; Membranes, Artificial; Middle Aged; Oxidative Stress; Renal Dialysis; Up-Regulation; Vitamin E

A number of pathological conditions caused by oxidative stress have been reported in uremic patients undergoing maintenance hemodialysis (HD). Enhanced lipid peroxidation was previously observed in peripheral blood mononuclear cells (PBMCs) of HD patients. Upregulation of 5-lipoxygenase (5-Lox) activity and protein content with enhanced production of leukotriene B(4) (LTB(4)) and membrane lipoperoxides was also shown in PBMCs of HD patients. Administration of free vitamin E specifically inhibited 5-Lox activity without affecting gene expression at the protein level. To assess whether oral or intramuscular (IM) administration of vitamin E may suppress 5-Lox in HD patients, PBMCs from 16 subjects on maintenance HD therapy for at least 6 months were investigated before and after a short course of IM or oral administration of vitamin E (8 patients per group). PBMCs from 13 healthy controls were also evaluated and assumed as the reference standard. Vitamin E significantly reduced lipid peroxidation, LTB(4) content, and 5-Lox activity in PBMCs, whereas 5-Lox gene expression at the protein level was not affected. There were no significant differences in these parameters between patients treated with IM or oral vitamin E. PBMCs of HD patients showed enhanced membrane lipid peroxidation and release of LTB(4), both linked to upregulation of 5-LOX: 5-Lox activity and related oxidative stress were significantly (although not completely) suppressed by vitamin E regardless of the administration route.

Topics: Administration, Oral; Aged; Analysis of Variance; Arachidonate 5-Lipoxygenase; Case-Control Studies; Gene Expression Regulation, Enzymologic; Humans; Injections, Intramuscular; Kidney Failure, Chronic; Leukocytes, Mononuclear; Leukotriene B4; Membrane Lipids; Middle Aged; Oxidative Stress; Renal Dialysis; Up-Regulation; Vitamin E

The aim of our study was (1) to verify whether haemodialysis (HD) with cuprophane (CUP) and polyacrylonitrile (PAN) membranes is associated with the release of vasoactive leukotriene (LT) C4 and chemotactic LTB4 and (2) to analyse the respective roles of lipoxygenase and cyclo-oxygenase metabolites of arachidonic acid in membrane bio-incompatibility. The investigation was performed in 10 uremic patients using hollow-fibre dialysers and dialysed successively, in random order, with CUP and PAN membranes. The arterial and venous (from dialyser) blood was sampled for the measurement of biochemical parameters, plasma LTC4, LTB4 and prostaglandins (PG) 6-keto-F1 alpha, E2, F2 alpha and thromboxane B2 before and after 15, 30 and 240 min of HD. Eicosanoids were measured by RIA after prior extraction and HPLC separation.. CUP HD was associated with a marked early leukopenia and a delayed decrease in blood pO2. Simultaneously, plasma LTB4 and LTC4 increased significantly in arterial blood after 30 min of HD and in venous blood at the end of session of 240 min. Cyclo-oxygenase metabolites increased as well, but nonsignificantly, with a maximum at the end of HD. PAN HD did not significantly change white blood cell count, pO2, or plasma eicosanoid levels.. CUP membranes stimulate the release of proinflammatory and vasoactive LTB4 and LTC4. PAN membrane haemodialysis is without such side effects. The release of LTs may be an additional valuable marker of membrane bioincompatibility.

Topics: Acrylic Resins; Adult; Aged; Arachidonic Acid; Blood Proteins; Cellulose; Chemotaxis; Data Interpretation, Statistical; Eicosanoids; Female; Hematocrit; Humans; Kidney Failure, Chronic; Leukocyte Count; Leukotriene B4; Leukotriene C4; Lipoxygenase; Male; Materials Testing; Membranes, Artificial; Middle Aged; Prostaglandin-Endoperoxide Synthases; Renal Dialysis

Incorporation of myo-[2-3H]-inositol into peripheral blood mononuclear cells (PBMNC) and T-cell enriched lymphocytes was evaluated in in-vitro experiments in chronic renal failure (CRF) patients and healthy subjects. Incorporation of myo-[2-3H]-inositol into the cells of CRF patients on conservative and haemodialysis treatment was found to be impaired in comparison with that observed in normal cells. Following PHA stimulation of the cells of CRF patients myo-[2-3H]-inositol incorporation decreased even further, while it increased in normal cells. Five-hour haemodialysis session significantly depressed myoinositol incorporation into PBMNC, while its incorporation into T-cell enriched lymphocytes remained unaffected. Myoinositol incorporation into PBMNC and T-cell enriched lymphocytes was inhibited by prostaglandins and leukotrienes and was inversely related to the extent of pertussis toxinsensitive G protein activation. Reduced myoinositol incorporation into uraemic PHA-stimulated PBMNC may depend at least in part on their enhanced PGE2 and LTB4 release accompanied by increased intracellular cAMP production. In CRF impaired myoinositol incorporation into immune cells may prove the disarrangement in the early events of transmembrane signal transduction, which may share the responsibility for the cell-mediated immune defect in these patients.

Topics: Adult; Aluminum; Cell Membrane; Cells, Cultured; Cyclic AMP; Cyclooxygenase Inhibitors; Dinoprostone; Female; Fluorine; Humans; Inositol; Intracellular Fluid; Kidney Failure, Chronic; Leukotriene B4; Lipoxygenase Inhibitors; Male; Monocytes; Phytohemagglutinins; Renal Dialysis; T-Lymphocytes

Biocompatibility assessed by values of dialysis leukopenia, complement system activation, that of blood elements was compared in the first and second use of capillary dialyzers equipped with various membranes. In the dialyzers re-use biocompatibility improved. Electron microscopy of hollow fiber sections suggested the role of protein layer safety on the membrane surface in biocompatibility under successive employment of the dialyzers. Treatment of the latter with acetic and peracetic acids mixture proved advantageous against other methods. Clinical effect due to dialyzer re-use changed positively.

Topics: Analysis of Variance; beta-Thromboglobulin; Complement System Proteins; Equipment Reuse; Equipment Safety; Female; Humans; Kidney Failure, Chronic; Leukocyte Count; Leukotriene B4; Male; Membranes, Artificial; Renal Dialysis; Sterilization; Tumor Necrosis Factor-alpha

The role of cytokines in patients with chronic renal failure is currently under investigation. We therefore studied the release of leukotriene B4 (LTB4) from polymorphonuclear leukocytes (PMN) in stable dialysis patients treated with two different cellulose membranes, Cuprophan and Hemophan, a modified cellulose with less complement activation. Six patients were treated for four weeks with Cuprophan then switched to Hemophan for another four weeks. Before and after the last treatment of each period, PMN were separated from 20 ml heparinized blood by FICOLL density gradient centrifugation. Portions of 5 x 10(6) PMN were resuspended in Hanks' buffer and stimulated for 5 minutes with calcium ionophore A23187 (5 micrograms/ml). LTB4 in cell supernatants was determined by specific radioimmunoassay. PMN from dialysis patients before HD released significantly (p less than 0.01) more LTB4 than healthy donors. No significant difference between pre- and post-dialysis values was observed with Cuprophan or Hemophan dialyzers. Our data suggest that the acute effects of blood membrane interaction with either complement activating or non-activating dialyzers do not lead to changes in post-dialysis leukotriene metabolism, but leukotriene production is enhanced chronically in dialysis patients.

Topics: Adult; Aged; Cellulose; Humans; Kidney Failure, Chronic; Leukocyte Count; Leukotriene B4; Membranes, Artificial; Middle Aged; Neutrophils; Renal Dialysis

Biosynthesis of leukotriene B4 (LTB4) was studied in ten patients with end-stage renal failure undergoing chronic hemodialysis with a cuprophane membrane. As compared to healthy subjects the low basal plasma levels of LTB4 quantified by radioimmunoassay after extraction and purification by HPLC showed no significant difference. The time-course of LTB4 release after contact of the blood with the dialysis membrane without further in vitro stimulation was characterized by a rapid increase by about 500% within the first 10 min, appearing approximately at the same time as the known fall of white blood cell count which reaches its nadir after 20 min. Analysis of further release showed a decline of LTB4 biosynthesis to basal levels at the end of hemodialysis. These results indicate that activation of the 5-lipoxygenase pathway is involved in hemodialysis-associated leukopenia and may contribute to the alterations in neutrophils of patients with chronic dialysis therapy.

Topics: Arachidonate 5-Lipoxygenase; Enzyme Activation; Female; Humans; Kidney Failure, Chronic; Kinetics; Leukotriene B4; Male; Middle Aged; Neutropenia; Renal Dialysis

Topics: Adolescent; Child; Child, Preschool; Humans; Infant; Kidney Failure, Chronic; Leukotriene B4; Neutrophils

Prostanoids are local cyclooxygenase products, synthesized by mesangial and epithelial cells of the glomerulus as well as by a variety of inflammatory cells and platelets. Prostaglandins and thromboxane have direct vasodilatory and vasoconstrictory effects and can modulate glomerular function. Arachidonic acid, the main substrate for cyclooxygenase, can also be metabolized by the lipoxygenase pathway to leukotrienes, substances which are primarily synthesized in inflammatory cells. In several models induction of immunologic glomerular injury is associated with an increased glomerular formation of cyclooxygenase and lipoxygenase products. The changes in cyclooxygenase products have been shown to account for some hemodynamic changes found in some of these models. Increased renal prostanoid formation is also present in patients with glomerular disease. There is some evidence that increased renal PG-formation in patients with moderate glomerular disease regulates GFR and mediates proteinurie in some of these patients. Leukotrienes are chemotactive substances which modulate the function of inflammatory cells, stimulate the growth of mesangial cells, and constrict mesangial cells in culture. Thus, these compounds might be mediators in the induction of immune mediated glomerular disease.

Topics: Animals; Arachidonic Acid; Arachidonic Acids; Eicosanoic Acids; Glomerular Filtration Rate; Glomerulonephritis; Humans; Immune Complex Diseases; Kidney Failure, Chronic; Leukotriene B4; Lipoxygenase; Prostaglandin-Endoperoxide Synthases; Prostaglandins; Prostanoic Acids; Renal Circulation; SRS-A; Thromboxane A2