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)

Chronic experimental allergic encephalomyelitis (CEAE) is an established experimental model for multiple sclerosis (MS). The demyelinating lesions in the white matter of the central nervous system observed in CEAE and in MS are accompanied by various neurophysiological alterations. Among the best defined electrophysiological abnormalities are the changes in event-related potentials, in particular evoked potentials involving the spinal cord, i.e. motor and sensory evoked potentials. Less familiar are the changes observed in the electroencephalogram of CEAE-affected animals, which are also encountered in the human equivalent, MS. In the present experiment we evaluated the therapeutic value of a neurotrophic peptide treatment [H-Met(O2)-Glu-His-Phe-D-Lys-Phe-OH, an ACTH4-9 analogue] and its effect on the delayed flash visual evoked potentials (VEP) and power spectra of the electroencephalogram, during a 17-week follow-up of CEAE. CEAE animals treated with the neurotrophic peptide were protected against the development of neurological symptoms during the course of the demyelinating syndrome. VEPs of animals suffering from CEAE showed a delay of the latencies of the late components which was significantly counteracted by peptide treatment. The peak-to-peak amplitude of the VEP afterdischarge recorded from CEAE animals was significantly increased during the course of CEAE and correlated closely with the progression of the myelinopathy. Furthermore, CEAE animals showed an increase of electroencephalogram (EEG) beta activity of up to 500% as compared with the age-matched control group. This increase in beta power mainly consisted of a prevailing 20-21 Hz peak, a frequency that normally is not dominant in control EEG recordings of the rat during passive wakefulness. All these electrophysiological phenomena were absent in ACTH4-9 analogue-treated animals. The present findings underscore the potential importance of a neurotrophic peptide treatment in the pharmacotherapy of central demyelinating syndromes, and possibly of MS.
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PMID:Neurotrophic ACTH4-9 analogue therapy normalizes electroencephalographic alterations in chronic experimental allergic encephalomyelitis. 987 50

Acute hemorrhagic leukoencephalitis (AHL) is a rare and usually fatal disorder characterized clinically by an acute onset of neurologic abnormalities. It may occur in association with a viral illness or vaccination. Radiology and brain biopsy are essential for the diagnosis. The etiology of AHL is unclear. We postulated that viral/bacterial infection might be responsible, directly or through an immune-mediated mechanism, for this acute inflammatory myelinopathy. Fifteen cases of AHL were studied. Infectious agents, including varicella zoster virus (VZV), herpes simplex virus (HSV), human herpes virus-6 (HHV-6), cytomegalovirus, Epstein-Barr virus, and Mycoplasma, were investigated in brain specimens using the polymerase chain reaction (PCR), reverse transcriptase (RT)-PCR, and immunohistochemistry. Using PCR, HSV DNA was found in four cases, VZV DNA in two, and HHV-6 DNA in one. Among the control cases, two were HSV DNA positive. Further investigation to detect HSV RNA and antigens in HSV DNA-positive cases revealed that two cases with AHL were both HSV RNA and antigen positive. AHL is a hyperacute disease, which is considered the most acute form of acute disseminated encephalomyelitis (ADEM). Our findings suggests that a viral infection may be implicated in its pathogenesis, most likely through an indirect mechanism; however, as only a few cases of this rare disease were examined, statistical significance was not achieved. As a number of patients with disorders of the ADEM group may progress to develop multiple sclerosis (MS), we argue that an organism that has produced the former may remain in the brain tissue and be subsequently involved in the production of a self-sustained disorder such as MS.
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PMID:Detection of infectious agents in brain of patients with acute hemorrhagic leukoencephalitis. 1240 70

The primary target in multiple sclerosis (MS) is believed to be either myelin itself (myelinopathy) or the myelin-forming cell, the oligodendrocyte (oligodendrogliopathy). Although axonal injury occurs in MS, it is regarded as a secondary event to the myelin damage. Here, the lesion develops from myelin (outside) to the axon (inside) (Outside-In model). Recently, gray matter lesions and axonal injury in normal-appearing white matter have also been reported in MS. This raises two questions. 1) Is axonal injury exclusively secondary to myelin damage or from a direct insult to the axon or neurons (axonopathy)? (2) Is the injured axon regarded as only an end result of pathology or disease, or can axonal injury contribute to the spread of secondary damage, including demyelination? The former is raised from the fact that axonal damage has been reported in several virus infections, including human immunodeficiency virus, human T-lymphotropic virus 1, herpes simplex virus and coronavirus, which also cause demyelination. The latter possibility where axonal injury leads to other changes is raised from the rather unexpected similarity between spinal cord injury (SCI) and MS where axonal injury, oligodendrocyte apoptosis and demyelination are all present. In SCI, transection of axons leads to delayed oligodendrocyte apoptosis with secondary demyelination. Neurofilament immunostaining of spinal cord sections demonstrates that axonal injury with oligodendrocyte apoptosis also precedes demyelination in an animal model for MS, Theiler's murine encephalomyelitis virus infection. This implies that axonal injury could trigger demyelination. In this instance, lesions develop from the axon (inside) to the myelin (outside) (Inside-Out model).
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PMID:Inside-Out versus Outside-In models for virus induced demyelination: axonal damage triggering demyelination. 1250 60

It is assumed that the onset and course of autoimmune inflammatory central nervous system (CNS) disorders (eg, multiple sclerosis) are influenced by factors that afflict immune regulation as well as CNS vulnerability. We challenged this concept experimentally by investigating how genetic alterations that affect myelin (primary oligodendrocyte damage in PLPtg mice) and/or T-cell regulation (deficiency of PD-1) influence both the onset and course of an experimental autoimmune CNS inflammatory disease [MOG(35-55)-induced experimental autoimmune encephalomyelitis (EAE)]. We observed that double pathology was associated with a significantly earlier onset of disease, a slight increase in the neurological score, an increase in the number of infiltrating cells, and enhanced axonal degeneration compared with wild-type mice and the respective, single mutant controls. Double-mutant PLPtg/PD-1(-/-) mice showed an increased production of interferon-gamma by CNS immune cells at the peak of disease. Neither PD-1 deficiency nor oligodendropathy led to detectable spread of antigenic MHC class I- or class II-restricted epitopes during EAE. However, absence of PD-1 clearly increased the propensity of T lymphocytes to expand, and the number of clonal expansions reliably reflected the severity of the EAE disease course. Our data show that the interplay between immune dysregulation and myelinopathy results in a stable exacerbation of actively induced autoimmune CNS inflammation, suggesting that the combination of several pathological issues contributes significantly to disease susceptibility or relapses in human disease.
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PMID:Accelerated course of experimental autoimmune encephalomyelitis in PD-1-deficient central nervous system myelin mutants. 1944 4