leukotriene-b4 and Glomerulonephritis

Topics: Animals; Arachidonic Acid; Arachidonic Acids; Blood Cells; Cells, Cultured; Free Radicals; Glomerulonephritis; Humans; Inflammation; Kidney Glomerulus; Leukotriene B4; Lipoxygenase; Membrane Lipids; Oxygen; Prostaglandin-Endoperoxide Synthases; Prostaglandins; Rats; SRS-A; Thromboxanes

Crescent formation is the most important pathological finding that defines the prognosis of nephritis. Although neutrophils are known to play an important role in the progression of crescentic glomerulonephritis, such as anti-neutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis, the key chemoattractant for neutrophils in ANCA-associated glomerulonephritis has not been identified. Here, we demonstrate that a lipid chemoattractant, leukotriene B

Topics: Animals; Antibodies, Antineutrophil Cytoplasmic; Antigen-Antibody Complex; Chemotactic Factors; Glomerulonephritis; Leukotriene B4; Mice; Neutrophils; Receptors, Leukotriene B4

Anti-inflammatory effects of the 15-lipoxygenase (15-LO) derivatives lipoxin A(4) (LXA(4)) and 15-S-hydroxyeicosatetraenoic acid (15-S-HETE) have been documented in many experimental models of acute inflammation. However, the expression levels of 15-LO and its products in human renal diseases remain unknown. This study investigated the expression levels of LXA(4), leukotriene B(4) (LTB(4)), and 15-LO in leukocytes and glomeruli obtained from 22 children with acute poststreptococcal glomerulonephritis (APSGN), and determined the modulatory effects of both 15-S-HETE and LXA(4) on LTB(4) synthesis in leukocytes and LTB(4)-evoked chemotaxis of polymorphonuclear leukocytes (PMNs) obtained from children during the first 3 days after onset of APSGN. Expression levels of both LXA(4) and 15-LO in leukocytes and glomeruli were up-regulated during the acute phase of disease, further peaking between days 10 and 14, and remained increased after 6 to 8 weeks of APSGN onset. In contrast, blood and urinary levels of LTB(4) as well as the number of glomerular PMNs peaked during the acute phase of disease and then decreased during the resolution phase. Administration of both 15-S-HETE and LXA(4) in vitro inhibited LTB(4)-induced chemotaxis of PMNs and production of LTB(4) from leukocytes obtained from patients with APSGN. The current study provides further support for an anti-inflammatory role for 15-LO products in human nephritis through both antagonism and inhibition of leukotriene synthesis and its biological activity.

Topics: Arachidonate 15-Lipoxygenase; Chemotaxis, Leukocyte; Child; Child, Preschool; Enzyme-Linked Immunosorbent Assay; Glomerulonephritis; Humans; Hydroxyeicosatetraenoic Acids; Immunohistochemistry; Leukocytes; Leukotriene B4; Lipoxins; Neutrophils; Streptococcal Infections

The human 15-lipoxygenase (15-LO) gene was transfected into rat kidneys in vivo via intra-renal arterial injection. Three days later, acute (passive) or accelerated forms of antiglomerular basement membrane antibody-mediated glomerulonephritis were induced in transfected and nontransfected or sham-transfected controls. Studies of glomerular functions (filtration and protein excretion) and ex vivo glomerular leukotriene B(4) biosynthesis at 3 hr, and up to 4 days, after induction of nephritis revealed preservation or normalization of these parameters in transfected kidneys that expressed human 15-LO mRNA and mature protein, but not in contralateral control kidneys or sham-transfected animals. The results provide in vivo-derived data supporting a direct anti-inflammatory role for 15-LO during immune-mediated tissue injury.

Topics: Animals; Arachidonate 15-Lipoxygenase; Eicosapentaenoic Acid; Genetic Therapy; Glomerular Filtration Rate; Glomerulonephritis; Green Fluorescent Proteins; Humans; Immunohistochemistry; Kidney; Leukotriene B4; Luminescent Proteins; Male; Rats; Rats, Sprague-Dawley; Transfection

Topics: Animals; Cytokines; Epoxide Hydrolases; Gene Expression; Glomerulonephritis; Humans; Immunohistochemistry; In Vitro Techniques; Interferon-gamma; Interleukin-1; Interleukin-13; Interleukin-4; Leukotriene B4; Male; Monocytes; Rats; Rats, Sprague-Dawley; Recombinant Proteins; RNA, Messenger; Th1 Cells; Th2 Cells

Three hours following injection of anti-GBM (glomerular basement membrane) antibody (10 mg/kg, i.v.) into rats, glomerular production of LTB4 was significantly increased as compared to untreated rats (497 +/- 26 vs. 244 +/- 18 pg of LTB4/mg protein). Twenty-four hours following administration of anti-GBM antibody, renal function (blood urea nitrogen, BUN; plasma creatinine, PCr; creatinine clearance, CCr; fractional excretion of sodium, FENa; fractional excretion of urea, FEUrea) was determined to be impaired proportionally to the amount of injected antibody (5 to 30 mg/kg, i.v.). In a second series of experiments, a selective 5-lipoxygenase (5-LO) inhibitor, SK&F 107649, was used to investigate the involvement of 5-LO products in the pathophysiology of anti-GBM antibody-induced glomerulonephritis. In preliminary experiments. SK&F 107649 (50 to 200 mg/kg, p.o.) inhibited ionophore (A23187)-stimulated whole blood leukotriene (LT) B4 production in a dose-dependent fashion (P < 0.05 at doses > or = 100 mg/kg). The anti-GBM antibody-mediated decrease in glomerular filtration rate (GFR) and increase in BUN and PCr were dose-dependently attenuated by SK&F 107649 (50 to 200 mg/kg, p.o. BID). These data confirm that glomerular LTB4 production is stimulated in anti-GBM antibody-induced glomerulonephritis, and demonstrate that inhibition of 5-LO by SK&F 107649 normalizes BUN and PCr and attenuate the decrease in GFR following anti-GBM antibody treatment. These results provide additional evidence for a role of 5-LO products in immune-mediated renal disease, and suggest that pharmacologic inhibition of 5-LO may be of therapeutic value.

Topics: Animals; Arachidonate 5-Lipoxygenase; Basement Membrane; Dose-Response Relationship, Drug; Fluorescent Antibody Technique; Glomerular Filtration Rate; Glomerulonephritis; Immunoglobulin G; Kidney Glomerulus; Leukotriene B4; Lipoxygenase Inhibitors; Male; Rats; Rats, Sprague-Dawley; Sheep; Tetrahydronaphthalenes; Urea

The modulatory effect of arachidonate 5-lipoxygenation on glomerular cell growth was assessed in rat nephrotoxic serum nephritis (NSN). After a single intravenous injection of anti-glomerular basement membrane immune serum, significant increments in glomerular proliferative activity (GPA)--assessed by tritiated thymidine incorporation in short-term glomerular cultures--occurred and were associated with enhanced glomerular cell proliferation, assessed in cortical sections by staining for the presence of proliferating cell nuclear antigen (PCNA) positive cells in glomeruli. Leukocyte depletion induced by x irradiation ameliorated the enhanced GPA and reduced PCNA (+) cell counts. The same effect was observed after treatment of rats with the arachidonate 5-lipoxygenase inhibitor MK886. These observations indicate that in NSN, leukocytes infiltrating glomeruli, and leukocyte-derived arachidonate 5-lipoxygenation eicosanoids promote glomerular cell proliferation.

Topics: Animals; Arachidonate 5-Lipoxygenase; Basement Membrane; Cell Count; Cell Division; Glomerular Mesangium; Glomerulonephritis; Immune Sera; Indoles; Kidney Glomerulus; Leukocyte Count; Leukotriene B4; Lipoxygenase Inhibitors; Male; Microscopy, Electron; Rats; Rats, Sprague-Dawley; X-Rays

The role of arachidonate 12- and 5-lipoxygenation eicosanoids in mediating acute changes in renal hemodynamics was assessed in nephrotoxic serum nephritis (NSN) in the rat. Following a single intravenous injection of nephrotoxic serum (NTS), significant decrements in glomerular filtration rate (GFR) and renal blood flow (RBF) occurred at one hour, and were associated with increments in glomerular polymorphonuclear leukocyte (PMN) counts and in the synthesis of thromboxane (Tx) B2, leukotriene (LT) B4 and 12-hydroxyeicosatetraenoic acid (12-HETE). Pretreatment of rats with the arachidonate 12-lipoxygenase inhibitor, baicalein, partially but significantly ameliorated the decrements in GFR and RBF, and blocked the enhanced glomerular synthesis of 12-HETE following administration of NTS. Likewise, pretreatment of rats with the arachidonate 5-lipoxygenase inhibitor, U-66858, partially ameliorated the decrements in GFR and RBF induced by NTS. Combined pretreatment of rats with baicalein and U-66858 ameliorated the decrements in GFR and RBF to an extent no different to that of U-66858 alone. In rats pretreated with the LTB4 receptor antagonist, U-75302, GFR and RBF remained depressed to levels no different than in animals which received NTS alone. These observations indicate that in NSN, the acute decrements in GFR and RBF are partially mediated by 12-HETE and arachidonate 5-lipoxygenation products. Leukotrienes other than LTB4, such as LTD4 and LTC4, are the likely candidates.

Topics: 12-Hydroxy-5,8,10,14-eicosatetraenoic Acid; Animals; Arachidonate 12-Lipoxygenase; Arachidonate 5-Lipoxygenase; Basement Membrane; Glomerular Filtration Rate; Glomerulonephritis; Hemodynamics; Hydroxyeicosatetraenoic Acids; Kidney Glomerulus; Leukotriene B4; Male; Rats; Renal Circulation

Nephrotoxic nephritis, a model system for glomerulonephritis, is characterized by glomerular inflammation, proteinuria, and a marked increase in ex vivo glomerular eicosanoid production. This study addressed whether urinary eicosanoids might serve as noninvasive markers for glomerular inflammation and damage with nephrotoxic nephritis and its accelerated variant. Accelerated nephritis, relative to simple nephritis, was characterized by more substantial glomerular inflammation, particularly that due to neutrophils. Correspondingly, accelerated nephritis was accompanied by greater proteinuria and more marked elevations in glomerular eicosanoids generated ex vivo. With respect to urinary eicosanoids, thromboxane, but not leukotriene B4, was detected in the urine of normal animals. After the induction of nephrotoxic nephritis, urinary thromboxane was moderately elevated (twofold) and urinary leukotriene B4 was variably present (three of seven animals). In accelerated nephritis, urinary thromboxane was more markedly elevated (sixfold) and leukotriene B4 was consistently present. The presence of urinary leukotriene B4 was confirmed by gas chromatography/mass spectrometry. Urinary eicosanoids together correlated with glomerular leukocyte numbers and proteinuria by linear regression. Urinary leukotriene B4 individually correlated with glomerular neutrophil numbers. Renal metabolism of leukotriene B4 to omega oxidation products by the rat kidney was not apparent. These data validate that the enhanced glomerular eicosanoid metabolism seen in nephrotoxic nephritis takes place in vivo and additionally suggest that both urinary thromboxane and leukotriene B4 may serve as noninvasive markers for glomerular inflammation and damage. In light of these and prior studies, urinary thromboxane may be a general marker of glomerular inflammation and leukotriene B4 may be a more specific index of acute inflammation.

Topics: Animals; Biomarkers; Disease Models, Animal; Eicosanoids; Glomerulonephritis; In Vitro Techniques; Kidney Glomerulus; Leukotriene B4; Perfusion; Rats; Rats, Inbred Lew; Thromboxanes

Leukotriene B4 (LTB4) is the major 5-lipoxgenase product released during early experimental glomerulonephritis. To test its functional relevance, its actions in the normal rat kidney and its influence on renal function in the heterologous phase of mild nephrotoxic serum-induced glomerular injury were examined. Intrarenal administration of leukotriene B4 resulted in mild vasorelaxant and natriuretic responses which were shared by 12(R)-hydroxyeicosatetraenoic acid but not 12(S)-leukotriene B4 or 12(S)-hydroxyeicosatetraenoic acid, suggesting activation of a common recognition site with a requirement for 12(R) stereochemistry. The polymorphonuclear cell-specific activator, N-formyl-Met-Leu-Phe, stimulated leukotriene B4 production from isolated perfused kidneys harvested from nephrotoxic serum-treated rats to a significantly greater degree than from control animals treated with nonimmune rabbit serum. The renal production of leukotriene B4 correlated directly and strongly (r = 0.79, P less than 0.01) with renal myeloperoxidase activity, suggesting interdependence of leukotriene B4 generation and polymorphonuclear cell infiltration. In vivo, intrarenal administration of leukotriene B4 to rats with mild nephrotoxic serum-induced injury was associated with an increase in polymorphonuclear cell infiltration, reduction in renal plasma flow rate, and marked exacerbation of the fall in glomerular filtration rate, the latter correlating strongly with the number of infiltrating polymorphonuclear cells/glomerulus, whereas inhibition of 5-lipoxygenase led to preservation of glomerular filtration rate and abrogation of proteinuria. Thus, although devoid of vasoconstrictor actions in the normal kidney, increased intrarenal generation of leukotriene B4 during early nephrotoxic serum-induced glomerular injury amplifies leukocyte-dependent reductions in glomerular perfusion and filtration rates, likely due to enhancement of polymorphonuclear cell recruitment/activation.

Topics: Animals; Arachidonic Acid; Glomerular Filtration Rate; Glomerulonephritis; In Vitro Techniques; Kidney; Kidney Glomerulus; Leukotriene B4; Neutrophils; Perfusion; Rats; Rats, Inbred Strains; Renal Circulation

Topics: 6-Ketoprostaglandin F1 alpha; Animals; Antioxidants; Benzoquinones; Drug Design; Drug Evaluation, Preclinical; Free Radicals; Glomerulonephritis; Humans; Leukotriene B4; Lipoxygenase Inhibitors; Molecular Structure; Oxygen; Puromycin Aminonucleoside; Rats; Structure-Activity Relationship; Thromboxane B2; Thromboxane-A Synthase

Topics: Animals; Disease Models, Animal; Glomerular Filtration Rate; Glomerulonephritis; Leukotriene B4; Neutrophils; Rats; SRS-A

Topics: Animals; Chemotaxis; Fatty Acids, Essential; Glomerulonephritis; In Vitro Techniques; Kidney Glomerulus; Leukotriene B4; Macrophages; Mice; Mice, Inbred Strains; Reference Values

The glomerular synthesis of LTB4 was assessed in glomeruli isolated from rats with passive Heymann nephritis (PHN). PHN was induced by a single intravenous administration of proteinuric doses of immune sera raised in sheep against rat brush border tubular fraction Fx1A. At various time points following induction of the disease glomeruli were isolated and LTB4 synthesis was assessed under basal and phospholipase A2 activation conditions. LTB4 was measured by high pressure liquid chromatography and radioimmunoassay and was identified by UV spectroscopy. The role of complement system in mediating glomerular LTB4 synthesis was also assessed in a group of decomplemented rats using cobra venom factor and at various time points following administration of immune serum. Following induction of PHN, enhanced glomerular LTB4 synthesis was observed as early as one hour, peaked at five hours and returned toward control levels over the subsequent four days. The peak in glomerular LTB4 synthesis did not correlate with changes in glomerular neutrophiles or macrophages. A second increment of LTB4 synthesis occurred at the onset of heavy proteinuria (day 5). Complement depletion reduced proteinuria and the enhancement in LTB4 synthesis at day 5 but had no effect at earlier time points. The observations indicate that in non-inflammatory forms of glomerular immune injury the glomerular arachidonate 5-lipoxygenation is enhanced. This phenomenon has no apparent relationship with increased glomerular permeability to protein and may reflect the presence or activation of a leukotriene producing cell following intraglomerular interactions of Fx1A antigen, anti-Fx1A antibody and complement.

Topics: Animals; Chromatography, High Pressure Liquid; Complement C4; Complement System Proteins; Female; Glomerulonephritis; Kidney Glomerulus; Leukotriene B4; Radioimmunoassay; Rats; Rats, Inbred Lew; Time Factors

We examined glomerular synthesis of the 5-lipoxygenase metabolite, LTB4, in normal and immune-injured rat glomeruli. Glomeruli isolated from normal rats and from rats with nephrotoxic serum nephritis (NSN), passive Heymann nephritis (PHN) and cationic bovine gamma globulin (CBGG)-induced glomerulonephritis were incubated with the calcium ionophore A23187 (3 microM). Lipids in the glomeruli and media were extracted with ethyl acetate, and were purified and fractionated by HPLC. Immunoreactive-LTB4 (i-LTB4) was determined by radioimmunoassay on HPLC fractions with a detection limit of 50 pg of i-LTB4. A large peak of i-LTB4 that comigrated with authentic LTB4 was found exclusively in glomeruli isolated from the CBGG-injected rats. Addition of the lipoxygenase inhibitor BW755C (50 micrograms/ml) to glomerular incubation resulted in greater than 90% inhibition of i-LTB4. Synthesis of i-LTB4 by glomeruli from normal, NSN and PHN rats was undetectable. Glomerular LTB4 synthesis by CBGG-injected rats was confirmed by radiometric HPLC and by gas chromatography mass-spectroscopy (GC-MS) analysis. In order to rule out synthesis of LTB4 by neutrophils entrapped in the glomeruli, a group of rats received 1,000 rad total body x irradiation, with shielding of the kidneys before induction of CBGG glomerulonephritis. Despite greater than 95% reduction in total leukocyte count, glomerular synthesis of LTB4 remained enhanced. Augmented glomerular synthesis of the proinflammatory lipid, LTB4, in the CBGG model of glomerular disease could have an important role in the development of glomerular injury and proteinuria.

Topics: 4,5-Dihydro-1-(3-(trifluoromethyl)phenyl)-1H-pyrazol-3-amine; Animals; Anti-Inflammatory Agents, Non-Steroidal; Chromatography, High Pressure Liquid; Female; Fluorescent Antibody Technique; Gas Chromatography-Mass Spectrometry; Glomerulonephritis; Kidney Glomerulus; Leukotriene B4; Male; Microscopy, Electron; Nephritis; Neutrophils; Pyrazoles; Rabbits; Radioimmunoassay; Rats; Rats, Inbred Strains

The basal and stimulated synthesis of immunoassayable 12- and 5-monohydroxyeicosatetraenoic acids (HETE) and leukotrienes (LT) B4 and C4 was studied in glomeruli isolated from rats with nephrotoxic serum glomerulonephritis (NSGN) induced by low (30 micrograms/g body weight) or high (105 micrograms/g) doses of anti-rat glomerular basement membrane (GBM) immunoglobulin (Ig). In the early heterologous phase of the disease, low doses of anti-GBM Ig enhanced the basal synthesis of 12-HETE but not that of 5-HETE or LT. High anti-GBM Ig doses enhanced the basal synthesis of 5-HETE and LTB4 as well. Under stimulated conditions, enhanced glomerular production of 5-HETE and LTB4 occurred at 15 min after infusion of anti-GBM Ig, peaked at 1 h, and returned toward control levels by 24 h. At 48 h, 72 h, and on day 12, the synthesis of these eicosanoids was impaired. Neutrophile depletion only partially reduced glomerular eicosanoid synthesis after induction of NSGN whereas complement depletion significantly reduced 5-HETE, 12-HETE, and LTB4. These observations indicate that in the heterologous phase of NSGN there is enhanced but short-lived glomerular 5-HETE and LTB4 synthesis. This phenomenon is mediated by complement activation and may be an important proinflammatory event leading to capillary wall injury in the early stages of the disease.

Topics: Animals; Autoantibodies; Basement Membrane; Complement System Proteins; Dinoprostone; Dose-Response Relationship, Immunologic; Glomerulonephritis; Hydroxyeicosatetraenoic Acids; Immune Sera; Kidney Cortex; Kidney Glomerulus; Leukotriene B4; Male; Neutrophils; Prostaglandins E; Rats; Rats, Inbred Strains; SRS-A

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