Cornuside ameliorated experimental autoimmune encephalomyelitis by limiting the recruitment of CD4+ T lymphocytes in the spinal cord

We conducted this study to determine whether cornuside could improve the neurological deficit symptoms of experimental autoimmune encephalomyelitis (EAE) rats, as well as determine the potential involvement of CD4+ T lymphocytes, vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), and tumor necrosis factor-α (TNF-α). Altogether, 32 Lewis rats were randomly divided into control, EAE, EAE/prednisolone, and EAE/cornuside, wherein their neurological function was assessed every day. CD4+ T lymphocyte recruitment into the spinal cord (SC) was evaluated using immunohistochemistry. The VCAM-1, ICAM-1 and TNF-α mRNA expressions in the SC were determined by real-time quantitative PCR, and the VCAM-1 and ICAM-1 proteins were determined by western blotting. Compared to the control group, the EAE group rats with neurological deficits had enhanced CD4+ T lymphocyte infiltration and higher expression levels of VCAM-1, ICAM-1, and TNF-α in the SC. Meanwhile, compared with the EAE group, the EAE/cornuside and EAE/prednisolone groups had lower neurological scores, less CD4+ T lymphocyte infiltrations, and lower expression levels of VCAM-1, ICAM-1, and TNF-α in the SC. Thus, cornuside ameliorated EAE, which could be owed to the inhibition of CD4+ T lymphocyte recruitment and VCAM-1, ICAM-1, and TNF-α expressions in the SC

BJ-1108, a 6-Amino-2,4,5-trimethylpyridin-3-ol analogue, regulates differentiation of Th1 and Th17 cells to ameliorate experimental autoimmune encephalomyelitis

BACKGROUND: CD4+ T cells play an important role in the initiation of an immune response by providing help to other cells. Among the helper T subsets, interferon-γ (IFN-γ)-secreting T helper 1 (Th1) and IL-17-secreting T helper 17 (Th17) cells are indispensable for clearance of intracellular as well as extracellular pathogens. However, Th1 and Th17 cells are also associated with pathogenesis and contribute to the progression of multiple inflammatory conditions and autoimmune diseases. RESULTS: In the current study, we found that BJ-1108, a 6-aminopyridin-3-ol analogue, significantly inhibited Th1 and Th17 differentiation in vitro in a concentration-dependent manner, with no effect on proliferation or apoptosis of activated T cells. Moreover, BJ-1108 inhibited differentiation of Th1 and Th17 cells in ovalbumin (OVA)-specific OT II mice. A complete Freund's adjuvant (CFA)/OVA-induced inflammatory model revealed that BJ-1108 can reduce generation of proinflammatory Th1 and Th17 cells. Furthermore, in vivo studies showed that BJ-1108 delayed onset of disease and suppressed experimental autoimmune encephalomyelitis (EAE) disease progression by inhibiting differentiation of Th1 and Th17 cells. CONCLUSIONS: BJ-1108 treatment ameliorates inflammation and EAE by inhibiting Th1 and Th17 cells differentiation. Our findings suggest that BJ-1108 is a promising novel therapeutic agent for the treatment of inflammation and autoimmune disease.

Neumomediastino y necrosis cutánea en asociación a dermatomiositis: presentación de un caso clínico y revisión de la literatura / Pneumomediastinum and cutaneous necrosis in dermatomyositis: Report of one case

We report a 37 years old male with a dermatomyositis treated with oral cyclophosphamide. He was admitted to the hospital due to a zone of skin necrosis with purulent exudate, located in the second left toe. A complete blood count showed a leukocyte count of 2,600 cells/mm³. A Chest CAT scan showed a pneumomediastinum with emphysema of adjacent soft tissue. Cyclophosphamide was discontinued and leukocyte count improved. The affected toe was amputated and a chest CAT scan showed a partial resolution of the pneumomediastinum. We discuss and review the pathogenesis, clinical presentation and management of pneumomediastinum and cutaneous necrosis in association with dermatomyositis.

Therapeutic effects of all-trans retinoic acid on experimental autoimmune encephalomyelitis and its role in T-helper lymphocyte responses

Recent studies have demonstrated an essential role for IL-17 in the pathogenesis of experimental autoimmune encephalomyelitis [EAE]. Furthermore, it has been shown that FoxP3+Treg cells play an important role in the suppression of auto inflammatory reactions. Although, previous studies have determined the immunomodulatory potentials of all-trans-retinoic acid [ATRA], but these immunomodulations have been mostly justified by alteration in Thl/Th2 cytokines. The present study was carried out to investigate the therapeutic effects of ATRA on EAE and its effects on T-helper cells responses. EAE was induced by MOG[35-55] peptide and complete Freund's adjuvant in female C57BL/6 mice. The mice were allocated to two therapeutic groups [n=7 per group]. Treatment with ATRA [500 microg/mouse; every other day] was initiated in treatment group on day 12 when they developed a disability score. EAE controls received vehicle alone with the same schedule. Signs of disease were recorded daily until day 33 when the mice were sacrificed. Splenocytes were tested for proliferation by MTT test, cytokine production by ELISA and FoxP3[+] reg cell frequency by flowcytometry. ATRA significantly reduced the clinical signs of established EAE. Aside from decreasing lymphocytic proliferation [P<0.05], ATRA significantly inhibited the production of pro-inflammatory IL-17 [P<0.005] as well as IFN-gamma [P<0.0005] upon antigen-specific restimulation of splenocytes. FoxP3+Treg cell frequency and IL-10 levels were not altered significantly. However, IFN-gamma to IL-10 and IL-17 to IL-10 ratios decreased significantly [P<0.0005]. Parallel to reducing autoreactive lymphocyte proliferation and cytokine production in favor of pro-inflammatory cytokines, all-trans-retinoic acid ameliorated established experimental autoimmune encephalomyelitis

Thalidomide administration inhibits the clinical evolution of the experimental autoimmune encephalomyelitis (eae) in lewis rats: preliminar results

Multiple sclerosis (MS) is a chronic neurodegenerative inflammatory disease of the central nervous system. Several immunomodulatory agents have been used to prevent MS acute exacerbations. Tumor Necrosis factor alpha (TNFα) and interferon gamma (IFN-γ) are two major inflammatory mediators. Recently, we investigated in our laboratory the therapeutic value of thalidomide, a recognized TNF-α inhibitor, for the treatment of MS using the classical Lewis rat model of experimental autoimmune encephalomyelitis ( EAE). The experimental study revealed that thalidomide reduces the incidence of EAE development in 90% of the cases. Hence we hypothesized that thalidomide may be an important therapeutical tool for prevention of acute exacerbations of the MS.

The immunomodulator glatiramer acetate influences spinal motoneuron plasticity during the course of multiple sclerosis in an animal model

The immunomodulador glatiramer acetate (GA) has been shown to significantly reduce the severity of symptoms during the course of multiple sclerosis and in its animal model - experimental autoimmune encephalomyelitis (EAE). Since GA may influence the response of non-neuronal cells in the spinal cord, it is possible that, to some extent, this drug affects the synaptic changes induced during the exacerbation of EAE. In the present study, we investigated whether GA has a positive influence on the loss of inputs to the motoneurons during the course of EAE in rats. Lewis rats were subjected to EAE associated with GA or placebo treatment. The animals were sacrificed after 15 days of treatment and the spinal cords processed for immunohistochemical analysis and transmission electron microscopy. A correlation between the synaptic changes and glial activation was obtained by performing labeling of synaptophysin and glial fibrillary acidic protein using immunohistochemical analysis. Ultrastructural analysis of the terminals apposed to alpha motoneurons was also performed by electron transmission microscopy. Interestingly, although the GA treatment preserved synaptophysin labeling, it did not significantly reduce the glial reaction, indicating that inflammatory activity was still present. Also, ultrastructural analysis showed that GA treatment significantly prevented retraction of both F and S type terminals compared to placebo. The present results indicate that the immunomodulator GA has an influence on the stability of nerve terminals in the spinal cord, which in turn may contribute to its neuroprotective effects during the course of multiple sclerosis.

Baicalin reduces the severity of experimental autoimmune encephalomyelitis

Scutellaria baicalensis Georgi is one of the important medicinal herbs widely used for the treatment of various inflammatory diseases in Asia. Baicalin (BA) is a bioactive anti-inflammatory flavone found abundantly in Scutellaria baicalensis Georgi. To explore the therapeutic potential of BA, we examined the effects of systemic administration of the flavone (5 and 10 mg/kg, ip) on relapsing/remitting experimental autoimmune encephalomyelitis (EAE) induced by proteolipid protein 139-151 in SJL/J mice, an experimental model of multiple sclerosis. The mice treated with PBS or BA at day -1 and for 3 consecutive days were observed daily for clinical signs of disease up to 60 days after immunization. In the PBS-EAE group, neurological scores were: incidence (100 percent), mean day of onset (8.0 ± 0.73), peak clinical score (3.0 ± 0.4), and cumulative disease index (141.8 ± 19.4). In the BA-EAE group (5 or 10 mg kg-1 day-1, respectively), incidence (95 or 90 percent), mean day of onset (9.0 ± 0.80 or 9.2 ± 0.75; P = 0.000), peak clinical score (2.2 ± 0.3 or 2.0 ± 0.3; P = 0.000), and cumulative disease index (75.9 ± 10.1 or 62.9 ± 8.4; P = 0.000) decreased, accompanied by the histopathological findings (decrease of dense mononuclear infiltration surrounding vascellum) for the spinal cord. Additionally, the in vitro effects of BA (5, 10, and 25 µM) on mononuclear cells collected from popliteal and inguinal lymph nodes of day-10 EAE mice were evaluated using an MTT reduction assay for cell proliferation, and ELISA to measure IFN-g and IL-4 cytokines. Compared with the control group, BA caused an increase in IL-4 (EAE-DMSO: 3.56 ± 0.42 pg/mL vs EAE-BA (5, 10, and 25 µM): 6.03 ± 1.1, 7.83 ± 0.65, 10.54 ± 1.13 pg/mL, respectively; P < 0.001); but inhibited IFN-g (EAE-DMSO: 485.76 ± 25.13 pg/mL vs EAE-BA (5, 10, and 25 µM): 87.08 ± 9.24, 36.27 ± 5.44, 19.18 ± 2.93 pg/mL, respectively; P < 0.001) and the proliferation of mononuclear cells (EAE-DMSO:...

Effect of simvastatin on evolution of experimental autoimmune encephalomyelitis in C57BL/6 mice

Simvastatin is an inhibitor of 3-hydroxy-3-methylglutaryl coenzyme a reductase and widely used as cholesterol-lowering agent. It is a promising candidate for future treatment in multiple sclerosis [MS], as it has been shown to exhibit immunomodulatory and anti-inflammatory effects. This study examined the effect of simvastatin on the evolution of experimental autoimmune encephalomyelitis [EAE], as an animal model for MS. EAE was induced by immunization of 8 week old C57BL/6 mice with MOG35-55 peptide with complete Freunds adjuvant. Therapy with simvastatin [1mg/kg/every day given as oral] was started on day 3 before the immunization until 25 day after immunization Total antioxidant capacity [TAC] was assessed by ferric reducing-antioxidant power [FRAP] method. Nitric oxide [NO] production was also estimated by Griess reaction. The results show that simvastatin-treated mice had significantly less incidence and clinical score of EAE than non-treated [control] EAE induced mice [p=0.001 and p=0.0001, respectively]. Moreover, treated mice displayed a significantly delayed disease onset compared with control mice. Simvastatin significantly increased TAC and level serum uric acid [p=0.001], but had no effect on serum nitrite production. Our results suggest that simvastatin therapy may be effective in the prevention of symptomatic EAE. This resistance to encephalomyelitis may be associated with the inhibition of oxidative stress and the increase of antioxidant capacity

Increased expression of neuronal nitric oxide synthase in astrocytes and macrophages in the spinal cord of Lewis rats with autoimmune encephalomyelitis

Neuronal nitric oxide synthase (nNOS) is constitutively expressed in neurons of the central nervous system, where it plays a physiological role in neurotransmission. In this study, we examined the functional role of nNOS in experimental autoimmune encephalomyelitis(EAE). The effects of the specific nNOS inhibitor 7-nitroindazole on normal and EAE rats were studied by immunohistochemistry and Western blot analysis. We found that nNOS is constitutively expressed in the spinal cords of normal rats, whilst in the spinal cords of EAE rats, nNOS expression slightly increased, concomitant with the infiltration of T cells and macrophages. Immunohistochemical studies showed that nNOS expression in macrophages and astrocytes increased at the peak stage of EAE and declined thereafter. Treatment with 7-nitroindazole (30 mg/kg) significantly delayed the onset of EAE paralysis, but had no effect on either the incidence or the severity of the paralysis. These findings suggest that nNOs inhibition has a limited role in the induction of rat EAE, and that constitutive nNOS in the spinal cord functions as a novel neurotransmitter, rather than a pro-inflammatory agent.