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)

The question of what happens to cholesterol in the adult central nervous system during its slow turnover has been addressed using rats with brain and spinal cord labeled with [4-14C]cholesterol upon intracerebral injection of labeled cholesterol into rats at 10-12 days of age. At six months after injection, 14C was found only in the brain and spinal cord and was slowly released via the rat's urine. When labeled rats were given demyelinating agents (triethyl tin chloride, hexachlorophene, sodium cyanide) and when experimental allergic encephalomyelitis was induced, a measurable increase in urinary 14C label above control levels was found. It was concluded that there is a direct relationship between the experimental demyelination induced and the increased release of cholesterol metabolites into urine. The study suggests that a clinical method could be developed to determine the rate of central nervous system demyelination by measuring the amount of urinary cholesterol metabolites.
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PMID:Central nervous system demyelinating diseases and increased release of cholesterol into the urinary system of rats. 781 95

Proinflammatory cytokines, pathological iron deposition, and oxidative stress have been implicated in the pathogenesis of multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE). HO-1 mRNA levels and mitochondrial uptake of [(55)Fe]Cl(3)-derived iron were measured in rat astroglial cultures exposed to interleukin-1beta (IL-1beta) or tumor necrosis factor-alpha (TNF-alpha) alone or in combination with the heme oxygenase-1 (HO-1) inhibitors, tin mesoporphyrin (SnMP) or dexamthasone (DEX), or interferon beta1b (INF-beta). HO-1 expression in astrocytes was evaluated by immunohistochemical staining of spinal cord tissue derived from MS and control subjects. IL-1beta or TNF-alpha promoted sequestration of non-transferrin-derived (55)Fe by astroglial mitochondria. HO-1 inhibitors, mitochondrial permeability transition pore (MTP) blockers and antioxidants significantly attenuated cytokine-related mitochondrial iron sequestration in these cells. IFN-beta decreased HO-1 expression and mitochondrial iron sequestration in IL-1beta- and TNF-alpha-challenged astroglia. The percentage of astrocytes coexpressing HO-1 in affected spinal cord from MS patients (57.3% +/- 12.8%) was significantly greater (p < 0.05) than in normal spinal cord derived from controls subjects (15.4% +/- 8.4%). HO-1 is over-expressed in MS spinal cord astroglia and may promote mitochondrial iron deposition in MS plaques. In MS, IFN-beta may attenuate glial HO-1 gene induction and aberrant mitochondrial iron deposition accruing from exposure to proinflammatory cytokines.
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PMID:Proinflammatory cytokines promote glial heme oxygenase-1 expression and mitochondrial iron deposition: implications for multiple sclerosis. 1138 89

Increasing evidence shows that oxidative stress plays an important role in the pathogenesis of experimental autoimmune encephalomyelitis (EAE), an animal model of the human disease, multiple sclerosis (MS). Heme oxygenase-1 (HO-1) is a heat shock protein induced by oxidative stress. HO-1 metabolizes heme to the antioxidant bilirubin and carbon monoxide, and represents a powerful endogenous defensive mechanism against free radicals in many diseases. However, the role of this important enzyme in EAE remains unknown. In this study, we showed high expression of HO-1 in lesions of EAE, and demonstrated that hemin, an inducer of HO-1, inhibited EAE effectively. In contrast, tin mesoporphyrin, an inhibitor of HO-1, markedly exacerbated EAE. Our results suggest that endogenous HO-1 plays an important protective role in EAE, and that targeted induction of HO-1 overexpression may represent a new therapy for the treatment of multiple sclerosis.
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PMID:Heme oxygenase-1 plays an important protective role in experimental autoimmune encephalomyelitis. 1143 9

The expression of heme oxygenase-1 (HO-1) is increased in the CNS of mice and rats with experimental allergic encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). To investigate the role of HO-1 in EAE, a putative inhibitor [tin-protoporphyrin IX (Sn-PP IX)] of HO-1 was administered to SJL mice during active disease. Sn-PP IX (200 micromol/kg) attenuated clinical scores, weight loss, and some signs of pathology in comparison to vehicle treatment. Glutathione levels were greater in treated EAE mice than in those receiving vehicle, indicating lower oxidative stress in the former group. These data suggest that inhibition of HO-1 attenuated disease and suppressed free radical production. In the SJL model of EAE, extravasated blood is present in the CNS, and iron released by HO-1 from this heme source may not be adequately sequestered by ferritin, allowing for iron-mediated tissue damage. Thus, HO-1 may act to amplify the disease process in this model.
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PMID:Heme oxygenase-1 in SJL mice with experimental allergic encephalomyelitis. 1292 42

Metallic tin powder is known to have an adjuvant-like property, by which it increases the levels of natural antibodies and induced hemagglutinins, and it enhances the induction of allergic encephalomyelitis in rats. In the present work, metallic tin is shown to be an adjuvant for a different immunologic process, anaphylactic sensitization. The new data support the notion that metallic tin causes polyclonal B-cell activation with proliferation of plasma cells.
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PMID:Metallic tin is an adjuvant for anaphylaxis in rats. 1513 23