Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0014070 (encephalomyelitis)
 13,017 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Estrogen has been reported to have immunosuppressive functions, and to inhibit the progression of experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). Since estrogen shows its biological effects via estrogen receptors (ER), we investigate the possible role of ER genes (ERG) in the pathogenesis of MS. PvuII and XbaI polymorphisms in ERG were detected by PCR-RFLP from the DNA of 79 conventional MS patients and 73 healthy controls. The [P] allele in the profiles in PvuII was significantly more prevalent in MS patients than in the controls (P<0.0005). In the study of XbaI polymorphism, the onset age of MS patients with the Xx genotype was earlier than that of the xx genotype group (mean age+/-S.D.; 22.60+/-8.04, and 27.49+/-9.14, respectively) (P<0.05) by ANOVA followed by Fisher's PLSD. Although the Xx genotype group tended to earlier onset age than the XX genotype group (29.60+/-11.10), this difference did not reach. On the basis of these results, PvuII polymorphism might be associated with susceptibility to MS, and XbaI polymorphism with onset age of MS. ERG polymorphism should be further studied in other populations to improve strategies for treatment of MS.
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PMID:Estrogen receptor gene polymorphism in Japanese patients with multiple sclerosis. 1105 88

A shift toward Th2 cytokine production has been demonstrated during pregnancy and high dose estrogen therapy and is thought to be the primary mechanism by which estrogen suppresses the development of experimental autoimmune encephalomyelitis. However, low dose estrogen treatment is equally protective in the absence of a significant shift in cytokine production. In this study cytokine-deficient mice were treated with estrogen to determine whether a shift in Th2 cytokine production was required for the protective effects of hormone therapy. Estrogen effectively suppressed the development of experimental autoimmune encephalomyelitis in IL-4 and IL-10 knockout mice and in wild type littermate mice with a similar potency of protection. Significant disease suppression was also seen in IFN-gamma-deficient mice. The decrease in disease severity was accompanied by a concomitant reduction in the number of proinflammatory cytokine- and chemokine-producing cells in the CNS. Although there was no apparent increase in compensatory Th2 cytokine production in cytokine-deficient mice, there was a profound decrease in the frequency of TNF-alpha-producing cells in the CNS and the periphery. Therefore, we propose that one mechanism by which estrogen protects females from the development of cell-mediated autoimmunity is through a hormone-dependent regulation of TNF-alpha production.
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PMID:Estrogen treatment down-regulates TNF-alpha production and reduces the severity of experimental autoimmune encephalomyelitis in cytokine knockout mice. 1141 93

Estrogen treatment has been found to have suppressive activity in several models of autoimmunity. To investigate the mechanism of 17 beta-estradiol (E2) suppression of experimental autoimmune encephalomyelitis, we evaluated E2 effects on TNF-alpha expression in the central nervous system (CNS) and spleen of C57BL/6 mice immunized with MOG 35-55/CFA. Kinetic analysis demonstrated that E2 treatment drastically decreased the recruitment of total inflammatory cells as well as TNF-alpha(+) macrophages and T cells into the CNS at disease onset. In contrast, E2 had only moderate effects on the relatively high constitutive TNF-alpha expression by resident CNS microglial cells. E2 treatment also had profound inhibitory effects on expression of TNF-alpha by splenic CD4(+) T cells, including those responsive to MOG 35-55 peptide. We propose that the mechanism of E2 protection may involve both systemic inhibition of TNF-alpha expression and local (CNS) recruitment of inflammatory cells, with modest effects on TNF-alpha expression by resident CNS microglial cells.
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PMID:Estrogen inhibits systemic T cell expression of TNF-alpha and recruitment of TNF-alpha(+) T cells and macrophages into the CNS of mice developing experimental encephalomyelitis. 1189 Jul 14

Estrogen has been found to have suppressive effects on the induction of experimental autoimmune encephalomyelitis (EAE), an animal model for the human disease multiple sclerosis. We have investigated the effects of 17beta-estradiol (E2) treatment on dendritic cells (DCs) in two different mouse models of EAE. The frequency of CD11b(+)/CD11c(+) DCs was significantly decreased in the brain of mice protected from EAE induction by E2 treatment. In addition, the frequency of CD11c(+)/CD8alpha(+) DCs producing tumor necrosis factor (TNF)alpha and interferon (IFN)gamma in the spleen of E2-treated mice was dramatically decreased compared to that in control mice with EAE, demonstrating an effect of E2 on DC function. In order to examine E2 effects on DCs in more detail, splenic DCs were cultured in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin (IL)-4 to promote maturation. E2 pretreatment was found to suppress the ability of cultured DCs bearing a mature phenotype to present Ag to myelin basic protein (MBP)-specific T cells. Analysis of cytokine production demonstrated that E2 decreased TNFalpha, IFNgamma and IL-12 production in mature DCs. In addition, MBP-specific T cells cocultured with E2-pretreated mature DCs in the presence of antigen demonstrated a shift towards production of Th2 cytokines IL-4 and IL-10 and a concomitant decrease in the production of Th1 cytokines TNFalpha and IFNgamma. Thus, E2 treatment appears to have multiple effects on the DC population, which may contribute to a down-regulation or block in the activation of Th1 cells involved in the induction of EAE.
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PMID:Estrogen inhibition of EAE involves effects on dendritic cell function. 1227 73

It is now well documented that experimental autoimmune encephalomyelitis (EAE) can be effectively prevented by estrogen therapy. Previously, we identified a limited set of genes that were altered in spleens of mice protected from EAE by 17beta-estradiol (E2) treatment. As a continuation of these studies, we present here transcriptional changes in genes expressed in spinal cord tissue. The Affymetrix microarray system was used to screen more than 12,000 genes from E2-treated double transgenic (BV8S2 and AV4) female mice protected from EAE vs. control mice with severe EAE. We found that estrogen therapy had a profound inhibitory effect on the expressions of many immune-related genes in spinal cords. Estrogen significantly affected the transcription of 315 genes, 302 of which were down-regulated and only 13 that were up-regulated by > or = 2.4 fold. A number of genes encoding the histocompatibility complex, cytokines/receptors, chemokines, adhesion molecules, and signal transduction proteins were strongly down-regulated (> 20 fold) in estrogen-treated mice to levels similar to those of the spinal cord tissue from unmanipulated mice. The identification of genes with altered expression patterns in the spinal cords of estrogen-treated mice provides unique insight into the process that ultimately results in protection against EAE.
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PMID:17Beta-estradiol treatment profoundly down-regulates gene expression in spinal cord tissue in mice protected from experimental autoimmune encephalomyelitis. 1289 73

Estrogen treatment has been found to be protective in experimental autoimmune encephalomyelitis (EAE) and possibly multiple sclerosis (MS). We investigated whether the effect of estrogen treatment is gender-specific. Estrogen receptor (ER) expressions, ERalpha and ERbeta, were found to be equivalent in both genders. EAE disease severity in both females and males was decreased with estriol treatment as compared to placebo. Finally, proinflammatory cytokine production during autoantigen-specific immune responses was decreased with estriol treatment in both females and males. These data support a potential role for estriol treatment for men in addition to women with MS.
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PMID:Estriol treatment ameliorates disease in males with experimental autoimmune encephalomyelitis: implications for multiple sclerosis. 1502 68

CD4(+)CD25(+) regulatory T cells are crucial to the maintenance of tolerance in normal individuals. However, the factors regulating this cell population and its function are largely unknown. Estrogen has been shown to protect against the development of autoimmune disease, yet the mechanism is not known. We demonstrate that estrogen (17-beta-estradiol, E2) is capable of augmenting FoxP3 expression in vitro and in vivo. Treatment of naive mice with E2 increased both CD25(+) cell number and FoxP3 expression level. Further, the ability of E2 to protect against autoimmune disease (experimental autoimmune encephalomyelitis) correlated with its ability to up-regulate FoxP3, as both were reduced in estrogen receptor alpha-deficient animals. Finally, E2 treatment and pregnancy induced FoxP3 protein expression to a similar degree, suggesting that high estrogen levels during pregnancy may help to maintain fetal tolerance. In summary, our data suggest E2 promotes tolerance by expanding the regulatory T cell compartment.
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PMID:Cutting edge: estrogen drives expansion of the CD4+CD25+ regulatory T cell compartment. 1529 32

Estrogen treatment has been shown to exert a protective effect on experimental autoimmune encephalomyelitis (EAE), and is under clinical trial for multiple sclerosis. Although it is commonly assumed that estrogens exert their effect by modulating immune functions, we show in this study that 17beta-estradiol (E2) treatment can inhibit mouse EAE without affecting autoantigen-specific T cell responsiveness and type 1 cytokine production. Using mutant mice in which estrogen receptor alpha (ERalpha) has been unambiguously inactivated, we found that ERalpha was responsible for the E2-mediated inhibition of EAE. We next generated irradiation bone marrow chimeras in which ERalpha expression was selectively impaired in inflammatory T lymphocytes or was limited to the radiosensitive hemopoietic compartment. Our data show that the protective effect of E2 on clinical EAE and CNS inflammation was not dependent on ERalpha signaling in inflammatory T cells. Likewise, EAE development was not prevented by E2 treatment in chimeric mice that selectively expressed ERalpha in the systemic immune compartment. In conclusion, our data demonstrate that the beneficial effect of E2 on this autoimmune disease does not involve ERalpha signaling in blood-derived inflammatory cells, and indicate that ERalpha expressed in other tissues, such as CNS-resident microglia or endothelial cells, mediates this effect.
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PMID:Estrogen receptor alpha signaling in inflammatory leukocytes is dispensable for 17beta-estradiol-mediated inhibition of experimental autoimmune encephalomyelitis. 1529 57

Estrogen results in the suppression of experimental allergic encephalomyelitis (EAE), a frequently used experimental animal model of multiple sclerosis (MS). The mechanism by which estrogen acts in diseases with an autoimmune background is less clear. Here, we used splenic dendritic cells (DC) from the Lewis rats EAE model as target cells, and explored the pathway of estrogen in immune modulation. Estrogen did not affect the expression of MHC class II, CD80 and CD86 by DC, but inhibited the ability of DC to stimulate T cell proliferation and production of both Th1 and Th2 cytokines. This was accompanied by increased T cell apoptosis. Estrogen up-regulated DC to express indoleamine 2,3-dioxygenase (IDO) which can limit T cell responses. The effects of estrogen-exposed DC on T cell proliferation and apoptosis were partly abolished by addition of an IDO inhibitor (1-methyl-dl-tryptophan, 1-MT), indicating that estrogen-exposed DC induced IDO-dependent T cell suppression. Our data support the hypothesis that the estrogen-induced suppression of EAE, as well as the reduction in number of MS relapses observed during pregnancy, may be related to the estrogen-DC-IDO axis. This observation could open up a novel therapeutic target for influencing the course of MS and other diseases with an autoimmune diseases background.
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PMID:Antigen-specific T cell functions are suppressed over the estrogen-dendritic cell-indoleamine 2,3-dioxygenase axis. 1546 10

Immunomodulatory effects of estrogen have been demonstrated by clinical and experimental observations, but the mechanisms by which estrogen exhibits the effects remain to be defined. One possible mechanism by which estrogen inhibits the development of experimental allergic encephalomyelitis (EAE), a commonly used model of multiple sclerosis (MS) in humans, is over the functions of dendritic cells (DC). Here, we describe that splenic DC from Lewis rats obtained on day 12 post-immunization (p.i.) with myelin basic protein (MBP) encephalitogenic peptide 68-86+Freund's complete adjuvant (FCA), after being exposed in vitro 17beta-estradiol, exhibited therapeutic effects on acute EAE when injected subcutaneously on day 5 p.i. Blood mononuclear cells (MNC) were isolated from thus treated rats on day 12 p.i. Administration of estrogen-exposed DC prevented the expansion of CD4+ T cells and increased proportions of regulatory T cells producing IL-10 and CD4+CD28- suppressor T cells, accompanied with increased IL-10 and IFN-gamma, and reduced TNF-alpha production. Infiltrates of CD68+ macrophages within the central nervous system and MBP 68-86-induced T cell proliferation were inhibited in rats injected with estrogen-exposed DC compared to rats injected with naive DC. Estrogen up-regulated the expression of indoleamine 2,3-dioxygenase, which promotes tolerogenic properties of DC. The results suggest that in vitro exposure of DC to estrogen modulates DC functions and results in a therapeutic effect of DC.
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PMID:Dendritic cells exposed to estrogen in vitro exhibit therapeutic effects in ongoing experimental allergic encephalomyelitis. 1546 96


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