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Query: UMLS:C0014070 (
encephalomyelitis
)
13,017
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Previous research has shown that the dual cyclo-oxygenase and
5-lipoxygenase
inhibitor, BW755c suppresses experimental autoimmune
encephalomyelitis
(EAE). In the present study, the effects of BW755c on both actively and passively induced EAE in the Lewis rat were examined, and also its effect on the accumulation of radiolabeled spleen cells in response to direct injection of tumor necrosis factor into the spinal cord. It was found that BW755c suppressed actively induced EAE but not passively induced EAE nor cytokine-induced cell accumulation in the central nervous system. It is concluded that arachidonic acid metabolites may be important in the induction phase of EAE, but do not appear to be crucial to the effector phase of EAE.
...
PMID:Suppression of active but not passive autoimmune encephalomyelitis by dual cyclo-oxygenase and 5-lipoxygenase inhibition. 157 3
It has recently been suggested that the sulfidopeptide leukotriene C4 (LTC4), a
5-lipoxygenase
product of the arachidonic acid metabolism and one of the most potent mediators of vascular permeability, might be involved in the pathogenesis of experimental autoimmune
encephalomyelitis
(EAE) and multiple sclerosis (MS). Subsequently, 20 guinea pigs with EAE were treated with sulfasalazine, a substance with a proved leukotriene inhibiting effect, which has previously been described as exerting beneficial effects in patients with inflammatory bowel disease and rheumatoid arthritis. The sulfasalazine-treated guinea pigs showed a significantly better clinical outcome, as well as a significantly lower histological inflammation score compared with 19 controls.
...
PMID:Suppression of experimental autoimmune encephalomyelitis by sulfasalazine. 168 88
The release of leukotriene C4 (LTC4), an important
5-lipoxygenase
product of the arachidonic acid metabolism from polymorphonuclear leucocytes (PMNLs) of guinea pigs with experimental allergic
encephalomyelitis
(EAE), the animal model of MS, has been found to be significantly increased compared with healthy animals. Subsequently, the dual cyclo-oxygenase and
5-lipoxygenase
inhibitor BW755C was applied to 15 guinea pigs with EAE. Two control groups (15 each) were treated with the cyclo-oxygenase inhibitor indomethacin or physiological saline, respectively. In the BW755C treated group, no animal developed symptoms of the disease in contrast to, respectively, 5 and 3 animals in the 2 other groups. Histological examination of the CNS revealed a highly significantly lower inflammation score in the BW755C treated animals, and the release of LTC4 from PMNLs was highly significantly decreased in this group compared with each of the others. The findings suggest that the vascular permeability enhancing LTC4 plays a pathogenetic role in EAE and indicate that inhibition of this sulfidopeptide leukotriene suppresses the disease. Therefore, the application of leukotriene inhibitors could contribute to the future treatment of MS.
...
PMID:Suppression of experimental autoimmune encephalomyelitis by dual cyclo-oxygenase and 5-lipoxygenase inhibition. 254 93
Rapamycin (RAPA), a potent immunosuppressive agent that prevents organ graft rejection in animal models of transplantation, possesses a mechanism of action different than that of cyclosporin A and FK-506. In this study, the pharmacological activity of RAPA in a variety of immune and inflammatory models was assessed in order to define better its potential utility as an antiarthritic agent. RAPA inhibited T cell-mediated inflammation in mouse methylated bovine serum albumin-induced delayed-type hypersensitivity (ED40 = 4.7 mg/kg p.o.) and produced oral ED50 of 2.0 mg/kg against developing adjuvant arthritis in rats (3-day dosing schedule) and 9.5 mg/kg in established adjuvant arthritis in rats (daily dosing schedule). In both models of adjuvant arthritis, effects of RAPA were maintained even after cessation of drug dosing. In contrast, after discontinuation of cyclosporin A (5- and 10-mg/kg doses), disease activity returned. RAPA was also effective in another T cell-mediated model, experimental allergic
encephalomyelitis
(ED50 approximately 5 mg/kg p.o.). At higher doses, RAPA significantly inhibited carrageenan paw edema in rats, a model of acute inflammation (ED40, 56 mg/kg p.o.), without increasing serum corticosterone levels. In this model, doses approximately 10 to 20 times greater than active doses in T cell-mediated models were required. RAPA at 1 to 50 microM did not inhibit in vitro human synovial phospholipase A2 or
5-lipoxygenase
and cyclo-oxygenase activity in the human blood leukocyte assay. The total profile of RAPA suggests that it may be effective in the treatment of rheumatoid arthritis, multiple sclerosis and other autoimmune diseases.
...
PMID:Rapamycin, a potential disease-modifying antiarthritic drug. 835 84
Mixed acetylboswellic acids, pentacyclic triterpenes extracted from the gum resin of Boswellia serrata Roxb., significantly inhibited the ionophore-stimulated release of the leukotrienes (LT) B4 and C4 from intact human polymorphonuclear neutrophil leukocytes (PMNLs), with IC50 values of 8.48 micrograms/ml and 8.43 micrograms/ml, respectively. Purified acetyl-11-keto-beta-boswellic acid was about three times more potent as inhibitor of the formation of both LTB4 (IC50 = 2.53 micrograms/ml) and LTC4 (IC50 = 2.26 micrograms/ml) from human PMNLs in the same assay. The comparative agent MK 886 (3-[1-(4-chlorobenzyl)-3-t-butyl-thio-5-isopropylindol-2-yl]- 2,2-dimethylpropanoic acid, L-663,536, CAS 118, 414-82-7) was about 10 to 100-fold more active than the boswellic acids in inhibiting the formation of
5-lipoxygenase
products in human PMNLs, with IC50 values of 0.0068 microgram/ml (LTB4) and 0.49 microgram/ml (LTC4). After daily intraperitoneal dosage the extract of mixed acetylboswellic acids (20 mg/kg) significantly reduced the clinical symptoms in guinea pigs with experimental autoimmune
encephalomyelitis
(EAE) between days 11 and 21. However, the inflammatory infiltrates in the brain and the spinal cord were not significantly less extensive in the treated animals than in the respective control group. The multiple intraperitoneal application of boswellic acids did not inhibit the ionophore-challenged ex vivo release of leukotrienes B4 and C4 from PMNLs separated from the blood of guinea pigs with EAE. The boswellic acids have thus been characterized as selective, non-redox and potent inhibitors of the biosynthesis of leukotrienes in vitro.
...
PMID:Effects of boswellic acids extracted from a herbal medicine on the biosynthesis of leukotrienes and the course of experimental autoimmune encephalomyelitis. 968 25
Multiple sclerosis (MS) is a demyelinating disease of the central nervous system characterized by lesions that are areas of blood-brain barrier breakdown, inflammation and myelin damage. To identify genes that contribute to lesion pathology, we have compared gene expression in MS lesions and in brains of mice with experimental allergic
encephalomyelitis
(EAE) with that in normal white matter. Gene expression was analyzed by cDNA microarrays consisting of 2798 human genes. One of the genes found to be upregulated in both MS lesions and EAE brains was
5-lipoxygenase
(
5-LO
), a key enzyme in the biosynthesis of the proinflammatory leukotrienes. The presence of
5-LO
in MS lesions was confirmed by immunohistochemistry and indicated that
5-LO
was primarily contained within macrophages. Although these findings are not specific for MS, they identify a potentially important component of pro-inflammatory activity in the demyelinating process in MS and suggest a possible target for anti-inflammatory therapy in MS.
...
PMID:Microarray analysis of gene expression in multiple sclerosis and EAE identifies 5-lipoxygenase as a component of inflammatory lesions. 1173 Sep 38
12/15-Lipoxygenase (12/15-LO) produces 15-hydroxyeicosatetraenoic acid (15-HETE) and 13-hydroxyoctadecadienoic acid (13-HODE) which are agonists for peroxisome proliferator-activated receptor-gamma (PPARgamma). PPARgamma agonists reduce clinical severity of experimental allergic
encephalomyelitis
(EAE), an animal model of multiple sclerosis. In contrast,
5-lipoxygenase
(
5-LO
) produces the generally proinflammatory leukotrienes (LTs) which would be expected to worsen EAE. We tested the hypotheses that EAE severity would be exacerbated in 12/15-LO-deficient mice and attenuated in
5-LO
-deficient mice. 12/15-LO deficiency conferred a significantly worse disease course, and surprisingly,
5-LO
deficiency also caused significantly more severe EAE compared to control mice. These data suggest that PPARgamma-regulated gene expression and that
5-LO
production of certain LTs have the ability to diminish EAE. Continued analysis will provide insight into the endogenous LO-generated effectors that assist in tempering EAE.
...
PMID:Experimental allergic encephalomyelitis is exacerbated in mice deficient for 12/15-lipoxygenase or 5-lipoxygenase. 1532 42
This study examined whether phenidone, a dual inhibitor of cyclooxygenase (COX) and lipoxygenase (LOX), affects the clinical symptoms of experimental autoimmune
encephalomyelitis
(EAE) in the rat, and the expression of both COX-1/-2 and
5-LOX
in EAE spinal cords. Oral phenidone (200 mg/kg) significantly suppressed the incidence and clinical severity of EAE paralysis. Western blot analysis showed that phenidone significantly inhibited the increases in COX-1/-2 and
5-LOX
in the spinal cords of rats with EAE. This finding was paralleled by immunohistochemical observations. Overall, these findings suggest that COX-1/-2 and
5-LOX
are important inflammatory mediators in the pathogenesis of EAE, and that the inhibition of both COX and LOX ameliorates the autoimmune disorder of the central nervous system.
...
PMID:Phenidone, a dual inhibitor of cyclooxygenases and lipoxygenases, ameliorates rat paralysis in experimental autoimmune encephalomyelitis by suppressing its target enzymes. 1572 60
Cytosolic phospholipase A2 alpha (cPLA2 alpha) is the rate-limiting enzyme for release of arachidonic acid, which is converted primarily to prostaglandins via the cyclooxygenase (COX) 1/2 pathways, and leukotrienes via the
5-lipoxygenase
(LO) pathway. We utilized inhibitors of cPLA2 alpha, COX-1/2 and 5-LO to determine the potential roles of these enzymes in development of experimental autoimmune
encephalomyelitis
(EAE), an animal model of multiple sclerosis (MS). Blocking cPLA2 alpha prevented EAE development and greatly reduced antigen-induced production of Th1-type cytokines and IL-17. Blocking COX-1/2 delayed onset and reduced severity of EAE, and reduced production of Th1-type cytokines, but not IL-17. Blocking 5-LO delayed onset and reduced cumulative severity of EAE, but did not reduce production of Th1-type cytokines or IL-17. Finally, blockade of cPLA2 alpha from the onset of clinical EAE reduced duration of EAE relapses. Therefore, cPLA2 alpha represents a potential therapeutic target for treatment of MS.
...
PMID:Blockade of cytosolic phospholipase A2 alpha prevents experimental autoimmune encephalomyelitis and diminishes development of Th1 and Th17 responses. 1882 19
The arachidonic acid (AA) cascade produces eicosanoids, such as prostaglandins (PGs), that regulate physiological and pathological functions. Although various nonsteroidal anti-inflammatory drugs have been developed, blocking upstream components (cyclooxygenase-1 and -2) of the AA cascade leads to severe side effects, including gastrointestinal ulcers and cardiovascular events, respectively, due to the complexity of the AA cascade. Here, using an AA cascade-targeted lipidomics approach, we report that microsomal PGE synthase 1 (mPGES-1) plays a key role in experimental autoimmune
encephalomyelitis
(EAE). Eicosanoids (mainly PGD(2)) are produced constitutively in the spinal cord of naive mice. However, in EAE lesions, the PGE(2) pathway is favored and the PGD(2), PGI(2), and
5-lipoxygenase
pathways are attenuated. Furthermore, mPGES-1(-/-) mice showed less severe symptoms of EAE and lower production of IL-17 and IFN-gamma than mPGES-1(+/+) mice. Expression of PGE(2) receptors (EP1, EP2, and EP4) was elevated in EAE lesions and correlated with clinical symptoms. Immunohistochemistry on central nervous systems of EAE mice and multiple sclerosis (MS) patients revealed overt expression of mPGES-1 protein in microglia/macrophages. Thus, the mPGES-1-PGE(2)-EPs axis of the AA cascade may exacerbate EAE pathology. Our findings have important implications for the design of therapies for MS.
...
PMID:Targeted lipidomics reveals mPGES-1-PGE2 as a therapeutic target for multiple sclerosis. 1999 78
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