Minimum structural requirements for encephalitogen and for adjuvant in the induction of experimental allergic encephalomyelitis.

Mycobacteria in the adjuvant used for induction of experimental autoimmune encephalomyelitis (EAE) in guinea pigs can be replaced by synthetic N-acetylmuramyl-l-alanyl-d-isoglutamine. A combination of synthetic encephalitogenic peptides and muramyl dipeptides induces EAE effectively at a dose on the microgram level. In this system, the synthetic heptapeptide, H-Trp-Gly-Ala-Glu-Gly-Gln-Arg-OH, with a sequence identical to those of residues 116 to 122 of the basic protein of human myelin, was the shortest peptide causing EAE. These compounds form a simple system which should be useful in studies on the mechanism of the cell-mediated autoimmune reaction.     

Glutamate receptors in neuroinflammatory demyelinating disease

Multiple sclerosis (MS) is a chronic demyelinating disease of the human central nervous system (CNS). The condition predominantly affects young adults and is characterised by immunological and inflammatory changes in the periphery and CNS that contribute to neurovascular disruption, haemopoietic cell invasion of target tissues, and demyelination of nerve fibres which culminate in neurological deficits that relapse and remit or are progressive. The main features of MS can be reproduced in the inducible animal counterpart, experimental autoimmune encephalomyelitis (EAE). The search for new MS treatments invariably employs EAE to determine drug activity and provide a rationale for exploring clinical efficacy. The preclinical development of compounds for MS has generally followed a conventional, immunotherapeutic route. However, over the past decade, a group of compounds that suppress EAE but have no apparent immunomodulatory activity have emerged. These drugs interact with the N-methyl-D-aspartate (NMDA) and alpha-amino-3-hydroxy-5-isoxazolepropionic acid (AMPA)/kainate family of glutamate receptors reported to control neurovascular permeability, inflammatory mediator synthesis, and resident glial cell functions including CNS myelination. The review considers the importance of the glutamate receptors in EAE and MS pathogenesis. The use of receptor antagonists to control EAE is also discussed together with the possibility of therapeutic application in demyelinating disease.     

Role of the protein fraction of Bordetella pertussis in inducing experimental allergic encephalomyelitis

B. pertussis protein fraction obtained by precipitation with trichloroacetic acid (TCA) stimulated the development of clinically and histologically pronounced experimental allergic encephalomyelitis (EAE) in guinea pigs when introduced together with a heterologous cerebral antigen, the two compounds forming an encephalitogenic mixture. The adjuvant activity of the TCA-precipitated fraction depended on its dose. The sera of the animals with EAE induced by the encephalitogenic mixture containing B. pertussis cells or TCA-precipitated fraction showed a cytopathogenic effect in the monolayer culture of newborn rat cerebellum cells. The cytopathogenic effect was more pronounced in the sera obtained at the period of the development of the clinical symptoms of the disease (days 14-18), while the cytotoxic effect of the sera obtained on day 30 after immunization decreased irrespective of the manifestations of EAE, this decrease being in correlation with the dose of the TCA-precipitated fraction in the encephalitogenic mixture.     

Neuropeptide Y (NPY) suppresses experimental autoimmune encephalomyelitis: NPY1 receptor-specific inhibition of autoreactive Th1 responses in vivo

Prior studies have revealed that the sympathetic nervous system regulates the clinical and pathological manifestations of experimental autoimmune encephalomyelitis (EAE), an autoimmune disease model mediated by Th1 T cells. Although the regulatory role of catecholamines has been indicated in the previous works, it remained possible that other sympathetic neurotransmitters like neuropeptide Y (NPY) may also be involved in the regulation of EAE. Here we examined the effect of NPY and NPY receptor subtype-specific compounds on EAE, actively induced with myelin oligodendrocyte glycoprotein 35-55 in C57BL/6 mice. Our results revealed that exogenous NPY as well as NPY Y(1) receptor agonists significantly inhibited the induction of EAE, whereas a Y(5) receptor agonist or a combined treatment of NPY with a Y(1) receptor antagonist did not inhibit signs of EAE. These results indicate that the suppression of EAE by NPY is mediated via Y(1) receptors. Furthermore, treatment with the Y(1) receptor antagonist induced a significantly earlier onset of EAE, indicating a protective role of endogenous NPY in the induction phase of EAE. We also revealed a significant inhibition of myelin oligodendrocyte glycoprotein 35-55-specific Th1 response as well as a Th2 bias of the autoimmune T cells in mice treated with the Y(1) receptor agonist. Ex vivo analysis further demonstrated that autoimmune T cells are directly affected by NPY via Y(1) receptors. Taken together, we conclude that NPY is a potent immunomodulator involved in the regulation of the Th1-mediated autoimmune disease EAE.     

Evaluation of the effects of a new drug candidate (GEMSP) in a chronic EAE model

Chronic Experimental Autoimmune Encephalomyelitis (EAE) was induced in rats to evaluate a new drug candidate (GEMSP) for the treatment of multiple sclerosis. This work is a part of preclinical studies on GEMSP, which is made up of fatty acids, vitamins and amino acids or their derivatives; all these compounds were linked to Poly-L-Lysine. In order to evaluate the effects of GEMSP, animals were divided into three experimental groups: 1) EAE rats treated with GEMSP; 2) EAE rats treated with NaCl; and 3) non-EAE rats. Using immunocytochemical techniques with a pan-leukocyte marker (anti-CD 45), differential leukocyte infiltration was compared in the central nervous systems of the different experimental groups. Antibodies directed against a component of GEMSP, the conjugated methionine, were used in all three groups. We found that: 1) GEMSP was effective in abolishing EAE. The crises and clinical scores were completely abolished in the animals of the first group, but not in the animals belonging to the second group; 2) the degree of leukocyte infiltration varied, depending on the different EAE stages, but was not related to the clinical score; and 3) after using anti-conjugated methionine antibodies, we observed immunoreactivity only in the motoneurons of the ventral horn of the spinal cord in the animals of the first group. This immunoreactivity was not found in the animals of the second or third groups. No methionine immunoreactivity was found in the brain. Our results suggest that GEMSP may be a potential drug candidate against the pathogenic processes involved in multiple sclerosis, inhibiting EAE episodes and brain leukocyte infiltration. Our results also show that one component of GEMSP, the methionine compound, is stored inside motoneurons. The possible physiological actions of GEMSP on spinal cord motoneurons are discussed.     

Highly oligomeric procyanidins ameliorate experimental autoimmune encephalomyelitis via suppression of Th1 immunity

Extracts of Jatoba, a South American herb, when injected i.p. into a mouse model of experimental autoimmune encephalomyelitis (EAE), inhibited the aggravation of clinical symptoms. At the same time, production of myelin oligodendrocyte glycoprotein Ag-specific IFN-gamma and TNF-alpha by spleen cells was markedly suppressed. After administration of Jatoba there was minimal evidence of the demyelination that is characteristic of the EAE model. Decreases in clinical scores were observed when Jatoba extracts were injected just before Ag. The purified active compounds are likely to be polyphenols that are absorbable to polyvinylpolypyrrolidone. The active compounds were polymerized polyphenol polymers (procyanidins) and at least five degrees of polymerization were necessary for activity. In addition, extracts of other plant materials containing such procyanidins had similar activity. After administration of highly polymerized procyanidins, there was a decrease in both dendritic and CD4(+) T cells. Although macrophages were increased in number, the expression of CD80 and MHC class II molecules was depressed indicating that the macrophages were immature. The results indicate that the suppression of development of EAE by the highly polymerized procyanidins resulted from an inhibition of Th1 and the effects might be associated with depression of Ag-presenting capability.     

Novel immunomodulatory properties of berbamine through selective down-regulation of STAT4 and action of IFN-gamma in experimental autoimmune encephalomyelitis

Berbamine (BM) is an herbal compound derived from Berberis vulgaris L commonly used in traditional Chinese medicine. In this study, we show that BM has potent anti-inflammatory properties through novel regulatory mechanisms, leading to reduced encephalitogenic T cell responses and amelioration of experimental autoimmune encephalomyelitis (EAE). The treatment effect of BM was attributable to its selective inhibitory effect on the production and action of IFN-gamma in CD4(+) T cells, which was mediated through altered STAT4 expression in T cells. BM was found to up-regulate SLIM, a ubiquitin E3 ligase for STAT4, and promote STAT4 degradation, resulting in markedly decreased IFN-gamma production in CD4(+) T cells in EAE mice. Regulation of IFN-gamma by BM had profound anti-inflammatory actions through its effect on both CD4(+) T cells and APCs. BM-treated APCs exhibited reduced stimulatory function as a result of altered expression of PD-L1, CD80, and CD86 in treated mice. The treatment effect of BM in EAE was directly related to its action on IFN-gamma, and was abolished in IFN-gamma knockout mice. The study also confirmed that BM was able to inhibit NFAT translocation through effecting calcium mobilization in lymphocytes. However, this effect was not directly responsible for the treatment efficacy of BM in EAE. The study has important implications in our approaches to evaluating the utility of natural compounds in drug discovery and to probing the role of cytokine network in the development of autoimmune conditions.     

三株亚肉座菌乙酸乙酯提取物生物活性及GC-MS分析

采用乙酸乙酯提取3株亚肉座菌菌丝体,测试虫生真菌乙酸乙酯提取物（EAE）的抗肿瘤、抗菌和抗氧化活性,并借助GC-MS方法分析各提取物中的化学成分。结果发现2株亚肉座菌的菌丝体EAE对HepG2细胞的抑制活性较强,IC₅₀均小于9μmol/L;抗菌结果表明2株真菌的提取物具有抑制细菌生长的作用;1株供试菌的EAE表现出较强的DPPH自由基清除活性（清除率可达85%）。GC-MS分析表明从亚肉座菌JXJG201717、JXJG201720和ARSEF7697的EAE中分别鉴定出21、35和39种成分,主要成分为酯类、醇类和酸类;盘状亚肉座菌JXJG201720与ARSEF7697有相同化合物13个,与暹罗亚肉座菌JXJG201717存在7个相同化合物。本研究表明虫生亚肉座菌具有产生丰富活性成分的能力,彰显出多种利用价值。     

黄芩内生真菌N.SBA10代谢产物抗氧化活性及结构鉴定

黄芩内生真菌N.SBA10固体发酵培养物的乙酸乙酯提取物有较好的抗氧化活性。从乙酸乙酯提取物中分离得到3个化合物,根据波谱数据,化合物1–3的结构分别被鉴定为：邻苯二甲酸二正丁酯（DBP）,alternariol methyl ether（AME）和alternariol（AOH）。     

Curcumin und Multiple Sklerose

Curcumin and Multiple Sclerosis In Multiple Sclerosis (MS), the inflammation caused by the patient's own immune system against the central nervous tissue leads to progressive loss of neurological functions. Reactive oxygenated species and nitric oxid, the latter produced by nitric oxid‐Synthases (NO) destroy axons and myelin sheets. In experimental autoimmune encephalomyelitis (EAE), an animal model for MS, arginase I expression is upregulated and an inhibition of arginase helps to delay the onset of EAE‐symptoms. Since arginases compete with NO for the substrate arginine, a complex network regulates NO activity. The prevalence of MS in societies, where curcumin is part of the daily diet, is lower than in the northern hemisphere. A specific inhibition of arginases by curcuma extract in vitro and evidence for a direct association of compounds therein with arginases suggests a perspective for the treatment of MS.     

Aminoguanidine and N-acetyl-cysteine supress oxidative and nitrosative stress in EAE rat brains

Experimental autoimmune encephalomyelitis (EAE) is a well-established animal model of human multiple sclerosis (MS). We have evaluated the role of oxidative and nitrosative stress, as the causal factors in the development of EAE, responsible for the damage of cardinal cellular components, such as lipids, proteins and nucleic acids, resulting in demyelination, axonal damage, and neuronal death. EAE was induced in female Sprague-Dawley rats, 3 months old (300±20 g), by immunization with myelin basic protein in combination with Complete Freund's adjuvant (CFA). The animals were divided into seven groups: control, EAE, CFA, EAE+aminoguanidine (AG), AG, EAE+N-acetyl-L-cysteine (NAC) and NAC. The animals were sacrificed 15 days after EAE induction, and the levels of nitrosative and oxidative stress were determined in 10% homogenate of the whole encephalitic mass. In EAE rats, brain NO production and MDA level were significantly increased (P<0.001) compared to the control values, whereas AG and NAC treatment decreased both parameters in EAE rats compared to EAE group (P<0.001). Glutathione (GSH) was reduced (P<0.001) in EAE rats in comparison with the control and CFA groups, but increased in EAE+AG and EAE+NAC group compared to the EAE group (P<0.01). Superoxide dismutase (SOD) activity was significantly decreased (P<0.001) in the EAE group compared to all other experimental groups. The clinical expression of EAE was significantly decreased (P<0.05) in the EAE groups treated with AG and NAC compared to EAE rats, during disease development. The obtained results prove an important role of oxidative and nitrosative stress in the pathogenesis of EAE, whereas AG and NAC protective effects offer new possibilities for a modified combined approach in MS therapy.     

The effect of apoptosis inhibitors on experimental autoimmune encephalomyelitis: apoptosis as a regulatory factor

The effect of apoptosis inhibitors on experimental autoimmune encephalomyelitis (EAE), a model for multiple sclerosis, was investigated by intraperitoneal or intracisternal administration of apoptosis inhibitors Ac-YVAD-cmk and zVAD-fmk. After onset of the disease, these agents had no suppressive effect on EAE and resulted in impaired recovery or earlier relapse. Histological examination revealed that administration of zVAD-fmk suppressed the apoptotic death of inflammatory cells in the central nervous system (CNS) of mice with EAE. The results indicated that the apoptotic elimination of infiltrated cells in the CNS might be one of the recovery mechanisms in EAE.     

Active induction of experimental allergic encephalomyelitis

This protocol details a method to actively induce experimental allergic encephalomyelitis (EAE), a widely used animal model for studies of multiple sclerosis. EAE is induced by stimulating T-cell-mediated immunity to myelin antigens. Active induction of EAE is accomplished by immunization with myelin antigens emulsified in adjuvant. This protocol focuses on induction of EAE in mice; however, the same principles apply to EAE induction in other species. EAE in rodents is manifested typically as ascending flaccid paralysis with inflammation targeting the spinal cord. However, more diverse clinical signs can occur in certain strain/antigen combinations in rodents and in other species, reflecting increased inflammation in the brain.     

Neurovascular damage in experimental allergic encephalomyelitis: a target for pharmacological control

The blood-brain barrier (BBB) is composed of a continuous endothelial layer with pericytes and astrocytes in close proximity to offer homeostatic control to the neurovasculature. The human demyelinating disease multiple sclerosis and the animal counterpart experimental allergic encephalomyelitis (EAE) are characterized by enhanced permeability of the BBB facilitating oedema formation and recruitment of systemically derived inflammatory-type cells into target tissues to mediate eventual myelin loss and neuronal dysfunction. EAE is considered a useful model for examining the pathology which culminates in loss of BBB integrity and the disease is now proving valuable in assessing compounds for efficacy in limiting damage at neurovascular sites. The precise mechanisms culminating in EAE-induced BBB breakdown are unclear although several potentially disruptive mediators have been implicated and have been previously identified as potent effectors of cerebrovascular damage in non-disease related conditions of the central nervous system. The review considers evidence that common mechanisms may mediate cerebrovascular permeability changes irrespective of the initial insult and discusses therapeutic approaches for the control of BBB leakage in the demyelinating diseases.     

MitoQ,a mitochondria-targeted antioxidant,delays disease progression and alleviates pathogenesis in an experimental autoimmune encephalomyelitis mouse model of multiple sclerosis

Oxidative stress and mitochondrial dysfunction are involved in the progression and pathogenesis of multiple sclerosis (MS). MitoQ is a mitochondria-targeted antioxidant that has a neuroprotective role in several mitochondrial and neurodegenerative diseases, including Alzheimer's disease and Parkinson's disease. Here we sought to determine the possible effects of a systematic administration of MitoQ as a therapy, using an experimental autoimmune encephalomyelitis (EAE) mouse model. We studied the beneficial effects of MitoQ in EAE mice that mimic MS like symptoms by treating EAE mice with MitoQ and pretreated C57BL6 mice with MitoQ plus EAE induction. We found that pretreatment and treatment of EAE mice with MitoQ reduced neurological disabilities associated with EAE. We also found that both pretreatment and treatment of the EAE mice with MitoQ significantly suppressed inflammatory markers of EAE, including the inhibition of inflammatory cytokines and chemokines. MitoQ treatments reduced neuronal cell loss in the spinal cord, a factor underlying motor disability in EAE mice. The neuroprotective role of MitoQ was confirmed by a neuron-glia co-culture system designed to mimic the mechanism of MS and EAE in vitro. We found that axonal inflammation and oxidative stress are associated with impaired behavioral functions in the EAE mouse model and that treatment with MitoQ can exert protective effects on neurons and reduce axonal inflammation and oxidative stress. These protective effects are likely via multiple mechanisms, including the attenuation of the robust immune response. These results suggest that MitoQ may be a new candidate for the treatment of MS.     

Synthesis and recovery of high bioactive phenolics from table-olive brine process wastewater

The generated wastewater of table-olive brine processing contains a high amount of polyphenols which are endowed with interesting biological activities. The ethyl acetate extract (EAE) of such wastewater shows high hydroxytyrosol (HT) and tyrosol concentrations of 690 and 98 mg g(-1) dry weight extract, respectively. Phenolic compounds analysis was performed by gas chromatography-mass spectrometry (GC-MS). The antioxidant activity was evaluated by the scavenging effect on DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2'-Azinobis[3-ethylbenzothiazoline-6-sulfonate] radicals. Total polyphenol content was estimated with the Folin-Ciocalteu assay. Hydroxytyrosol has DPPH and ABTS radicals scavenging activities higher than 2,6-di-tert-butyl-hydroxytoluene (BHT), while triacetylated hydroxytyrosol (triAcHT) was devoid of any antioxidant activity. The assessment of these antioxidant compounds in biological systems was carried out by the determination of their in vitro cytotoxicity against two different human cancer cell lines (HeLa and DG75) and normal peripheral blood lymphocytes (PBL) using the MTT assay. The 50% cytotoxic concentrations were ranged between 27 and 210 microg mL(-1) for Hela and DG75. At the same concentration range, the EAE and the pure HT and triAcHT exhibited an insignificant cytotoxicity against PBL. Incubation of HeLa and DG75 cells with non-cytotoxic concentrations of EAE, HT or triAcHT resulted in a remarkable protection from the oxidative stress induced by Fe(2+). The antimicrobial activity evaluated by the broth dilution NCCL method using Gram-positive (Staphylococcus aureus, Bacillus subtilis) and Gram-negative (Pseudomonas aeruginosa, Escherichia coli, Salmonella enterica) bacteria and (Candida albicans, Aspergillus niger) fungi showed a broad spectrum bactericidal and fungicidal effect of table-olives-EAE, HT and triAcHT. The MICs vary from 125 to 500 microg mL(-1) for bacteria and from 500 to 2000 microg mL(-1) for fungi.     

CD24 on the resident cells of the central nervous system enhances experimental autoimmune encephalomyelitis

CD24 is a cell surface glycoprotein that is expressed on both immune cells and cells of the CNS. We have previously shown that CD24 is required for the induction of experimental autoimmune encephalomyelitis (EAE), an experimental model for the human disease multiple sclerosis (MS). The development of EAE requires CD24 expression on both T cells and non-T host cells in the CNS. To understand the role of CD24 on the resident cells in the CNS during EAE development, we created CD24 bone marrow chimeras and transgenic mice in which CD24 expression was under the control of a glial fibrillary acidic protein promotor (AstroCD24TG mice). We showed that mice lacking CD24 expression on the CNS resident cells developed a mild form of EAE; in contrast, mice with overexpression of CD24 in the CNS developed severe EAE. Compared with nontransgenic mice, the CNS of AstroCD24TG mice had higher expression of cytokine genes such as IL-17 and demyelination-associated marker P8; the CNS of AstroCD24TG mice accumulated higher numbers of Th17 and total CD4+ T cells, whereas CD4+ T cells underwent more proliferation during EAE development. Expression of CD24 in CD24-deficient astrocytes also enhanced their costimulatory activity to myelin oligodendrocyte glycoprotein-specific, TCR-transgenic 2D2 T cells. Thus, CD24 on the resident cells in the CNS enhances EAE development via costimulation of encephalitogenic T cells. Because CD24 is increased drastically on resident cells in the CNS during EAE, our data have important implications for CD24-targeted therapy of MS.     

脑组织核因子-κB激活对实验性变态反应性脑脊髓炎的作用

为探讨脑组织核因子－κB（NF－κB）对实验性变态反应性脑脊髓炎（EAE）的作用,分别用凝胶电泳迁移分析和NF－κB p65免疫组化方法测定了CFA－GPSCH诱导大鼠EAE1、7、14和21d时脑组织NF－κB活性和蛋白表达的动态变化,并观察了这些变化与EAE症状之间的关系。结果表明;对照组大鼠脑组织仅有少量NF－κB蛋白表达,其活性也很低;诱导EAE后,伴随着大鼠EAE症状及脑组织病理损伤的出现和进行性加重,其NF－κB活性和蛋白表达量逐渐增高;在免疫后14d达到高峰,NF－κB阳性细胞主要位于脉络丛、穹隆下器、血管“套袖样”病灶的周围,与EAE病变部位一致,此时大鼠EAE发病率最高、病情最重、体重减轻最显著、脑组织病理改变也最明显;21h脑组织NF－κB活性和蛋白表达量逐渐下降,大鼠EAE症状也逐渐恢复。应用NF－κB特异性抑制剂PDTC以抑制脑内组织NF－κB活性和蛋白表达量逐渐下降,大鼠EAE症状也逐渐恢复。应用NF－κB特异性抑制剂PDTC以抑制脑内NF－κB蛋白表达后,大鼠EAE症状和脑组织损伤明显减轻,说明脑组织NF－κB的动态变化与EAE症状及脑组织损伤程度密切相关。结论：脑组织NF－κB的激活对EAE的发病起着关键的作用,应用NF－κB抑制剂可能是防治该病的有效方法之一。     

Prevention of experimental allergic encephalomyelitis (EAE) in the SJL/J mouse by whole body ultraviolet irradiation

The cellular requirements for the in vivo induction of experimental allergic encephalomyelitis (EAE) were investigated in the SJL/J mouse. Exposure of mice to whole body ultraviolet (UV) irradiation, a treatment that has been shown in other systems to interfere selectively with antigen-presenting cell function, prevented the development of clinical and pathologic signs of acute EAE. Splenic T cells from UV-treated animals did not adoptively transfer resistance to EAE, making it unlikely that UV irradiation resulted in the generation of a specific suppressor cell population responsible for protection from EAE. UV irradiation was effective in preventing EAE when administered before initial immunization; UV irradiation was ineffective in modifying ongoing EAE or in preventing relapses of EAE induced by reimmunization. In additional experiments, adult thymectomized, lethally x-irradiated mice reconstituted with syngeneic marrow cells depleted of mature T lymphocytes were found to be resistant to the induction of EAE. Susceptibility was restored by the addition of splenic T cells, demonstrating that EAE induction is T cell-dependent in the mouse. The prevention of an experimental autoimmune demyelinating disease by whole body UV irradiation suggests that interference with the function of Ia-bearing accessory cells may represent an approach for immunotherapy in autoimmune disorders.     

Adoptive transfer of experimental allergic encephalomyelitis in mice with the aid of pertussigen from Bordetella pertussis

Adoptive transfer of experimental allergic encephalomyelitis (EAE) in (SJL X BALB/c)F1 mice was accomplished by an iv injection of 2.4 to 4.7 X 10(7) lymph node cells (LNC) from mice immunized with mouse spinal cord emulsified in complete Freund's adjuvant when both donors and recipients had been treated iv with 400 ng of pertussigen at the time of immunization for the donors and on transfer of cells for the recipients. Pertussigen was essential in both donors and recipients for development of frank EAE. Signs of EAE in recipients were delayed, appearing 21-23 days after cell transfer; the maximum response at about Day 27 is considerably delayed in comparison with other reported studies on passive transfer of EAE. Histologically, recipient mice with paralysis due to EAE had typical perivascular infiltrates of mononuclear cells in the brain and spinal cord. The mechanisms by which pertussigen promotes the development of EAE after adoptive transfer of sensitized LNC are uncertain.