Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0085437 (bacterial meningitis)
 4,038 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

TNF-alpha, inducible NO synthase (iNOS), and ICAM-1 are considered to be key proteins in the inflammatory response of most tissues. We tested the hypothesis that cell walls of Streptococcus pneumoniae (PCW), the most common cause of adult bacterial meningitis, induce TNF-alpha, iNOS, and ICAM-1 expression in rat primary brain microvascular endothelial cell cultures. We detected TNF-alpha mRNA by RT-PCR already 1 h after stimulation with PCW, while TNF-alpha protein peaked at 4 h (9.4 +/- 3.6 vs 0.1 +/- 0.1 pg/microgram protein). PCW induced iNOS mRNA 2 h after stimulation, followed by an increase of the NO degradation product nitrite (18.1 +/- 4 vs 5.8 +/- 1.8 at 12 h; 18.1 +/- 4 vs 5.8 +/- 1.8 pmol/microgram protein at 72 h). The addition of TNF-alpha Ab significantly reduced nitrite production to 62.2 +/- 14.4% compared with PCW-stimulated brain microvascular endothelial cells (100%). PCW induced the expression of ICAM-1 (measured by FACS), which was completely blocked by TNF-alpha Ab (142 +/- 18.6 vs 97.5 +/- 12.4%; 100% unstimulated brain microvascular endothelial cells). Cerebral endothelial cells express TNF-alpha mRNA as well as iNOS mRNA and release the bioactive proteins in response to PCW. PCW-induced NO production is mediated in part by an autocrine pathway involving TNF-alpha, whereas ICAM-1 expression is completely mediated by this autocrine loop. By these mechanisms, cerebral endothelial cells may regulate critical steps in inflammatory blood-brain-barrier disruption of bacterial meningitis.
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PMID:Cerebral endothelial cells release TNF-alpha after stimulation with cell walls of Streptococcus pneumoniae and regulate inducible nitric oxide synthase and ICAM-1 expression via autocrine loops. 1051 Mar 70

A characteristic of human pathogenic Neisseriae is the production and secretion of an immunoglobulin (Ig)A1-specific serine protease (IgA1 protease) that cleaves preferentially human IgA1 and other target proteins. Here we show a novel function for native IgA1 protease, i.e., the induction of proinflammatory cytokines such as tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-6, and IL-8 from peripheral blood mononuclear cells. The capacity of IgA1 protease to elicit such cytokine responses in monocytes was enhanced in the presence of T lymphocytes. IgA1 protease did not induce the regulatory cytokine IL-10, which was, however, found in response to lipopolysaccharide and phytohemagglutinin. The immunomodulatory effects caused by IgA1 protease require a native form of the enzyme, and denaturation abolished cytokine induction. However, the proteolytic activity is not required for the cytokine induction by IgA1 protease. Our results indicate that IgA1 protease exhibits important immunostimulatory properties and may contribute substantially to the pathogenesis of neisserial infections by inducing large amounts of TNF-alpha and other proinflammatory cytokines. In particular, IgA1 protease may represent a key virulence determinant of bacterial meningitis.
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PMID:Immunoglobulin A1 protease, an exoenzyme of pathogenic Neisseriae, is a potent inducer of proinflammatory cytokines. 1052 3

This study was done to evaluate the anti-inflammatory effect and the ensuing neuroprotective effect of pentoxifylline in neonatal experimental bacterial meningitis. Newborn piglets were divided into three groups: 10 in the control group (CG), 13 in the meningitis group (MG), and 13 in the meningitis with pentoxifylline group (PG). Meningitis was induced by intracisternal injection of 10(8) colony-forming units of Escherichia coli in 100 microl of saline. In PG, 20 mg/kg of pentoxifylline was given as a bolus intravenous injection 30 min before induction of meningitis and 6 mg/kg/h was given continuously throughout the experiment. In PG, the increase of CSF TNF-alpha level observed in MG was abolished. Reduced brain glucose and ATP concentrations observed in MG were significantly increased in PG. However, other parameters of inflammatory responses such as increased intracranial pressure, reduced glucose and increased lactate concentrations in the CSF observed in MG were not significantly down-modulated. The extent of CSF leukocytosis was even higher in PG than in MG. Increased cerebral cortical cell membrane lipid peroxidation products and decreased Na(+),K(+)-ATPase activity observed in MG, indicative of meningitis-induced brain cell membrane dysfunction, tended to improve without statistical significance in PG. In summary, although some anti-inflammatory effects have been observed, the overall anti-inflammatory effects of pentoxifylline was very weak, and it failed to significantly reduce the brain damage in experimental neonatal bacterial meningitis.
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PMID:The efficacy of pentoxifylline as an anti-inflammatory agent in experimental Escherichia coli meningitis in the newborn piglet. 1082 75

In bacterial meningitis, neurological damage is associated with a high influx of polymorphonuclear leukocytes (PMN) into the brain. Previous data suggest that the capsular component of the fungus C. neoformans, glucuronoxylomannan (GXM), interferes with PMN-migration into the cerebrospinal fluid (CSF). Therefore, a rabbit model of bacterial meningitis was treated intravenously with GXM. This resulted in (1) a reduction of PMN in the CSF at 6 h (P=0.05), (2) reduced peak TNF-alpha concentrations in the CSF, and (3) diminished tissue inflammation and intravascular margination of PMN in GXM-treated animals. Thus, GXM may represent a novel adjuvant anti-inflammatory agent in bacterial meningitis.
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PMID:Cryptococcal glucuronoxylomannan delays translocation of leukocytes across the blood-brain barrier in an animal model of acute bacterial meningitis. 1106 16

Alpha-melanocyte-stimulating hormone (alpha-MSH) is an endogenous neuroimmunomodulatory peptide that can inhibit a broad range of inflammatory mediators known to be involved in the pathophysiology of bacterial meningitis. We evaluated the effect of alpha-MSH in a rat model of pneumococcal meningitis. Rats were intracisternally infected with Streptococcus pneumoniae and treatment was started 6 h after infection. Both systemic and intracisternal alpha-MSH failed to influence blood-brain barrier disruption, increased intracranial pressure, brain cytokine concentrations (IL-1beta, IL-6, TNF-alpha, MIP-2, and IL-10), CSF bacterial titers, and clinical parameters of disease severity (weight loss, body temperature, and blood pressure), although the treatment strongly increased the CNS concentrations of alpha-MSH. However, systemic but not intracisternal alpha-MSH slightly reduced the CNS leukocyte accumulation, indicating that leukocyte extravasation is inhibited by alpha-MSH from the blood side. Our results show that alpha-MSH reduces the CNS leukocyte accumulation by its systemic action, but does not attenuate meningitis-associated intracranial complications.
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PMID:Failure of alpha-melanocyte stimulating hormone to attenuate cerebral complications in experimental pneumococcal meningitis. 1131 30

Certain cytokines may contribute to the sequence of events that lead to meningeal inflammation in bacterial meningitis. The purpose of this study was to determine the levels of cytokines in the cerebrospinal fluid (CSF) of children with bacterial meningitis and aseptic meningitis of different etiologies. We determined the concentrations of interleukin-1beta (IL-1beta) and tumor necrosis factor (TNF-alpha) in the CSF of 171 specimens of 144 patients whose cases were classified as follow: bacterial meningitis (n=23), aseptic meningitis (n=26) and non-meningitis (n=95). The detectable IL-1beta concentration (> or =20 pg/ml) in the bacterial meningitis, aseptic meningitis and non-meningitis groups were observed with 78.3%, 3.8%, and 8.4%, respectively. Significantly higher serum IL-1beta concentrations were detected in those with bacterial meningitis than those with aseptic meningitis (538.93+/-605.32 pg/ml vs 2.52+/-11.57 pg/ml; P<0.001) or among non-meningitis subjects (2.90+/-11.91 pg/ml; P<0.001). The mean TNF-alpha concentration was 148.74+/-338.77 pg/ml. There was significantly more TNF-alpha than aseptic meningitis (6.85+/-17.93 pg/ml; P<0.001) or non-meningitis (7.67+/-16.07 pg/ml; P<0.001). With regard to diagnosis, measurement of IL-1beta and TNF-alpha levels showed sensitivities of 78% and 74%, respectively; specificities of 96% and 81%, respectively. It is suggested that the levels of these cytokines, especially IL-1beta and TNF-alpha, are useful markers for distinguishing bacterial meningitis from aseptic meningitis.
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PMID:Interleukin-1beta and tumor necrosis factor-alpha in cerebrospinal fluid of children with bacterial meningitis. 1150 33

Myeloid (CD11c+) dendritic cells (DC) are present in cerebrospinal fluid (CSF), as well as in the meninges and choroid plexus. Functional studies of these DC are hindered or impossible. To obviate this problem, we investigated the effects of CSF supernatants from patients with non-inflammatory neurological diseases (NIND), multiple sclerosis (MS), bacterial meningitis (BM) and Lyme meningoencephalitis (LM) on immature monocyte-derived DC (moDC) from healthy donors. CSF supernatants caused maturation of moDC (MS > LM > NIND > BM), as reflected by a decrease in CD1a, and an increase in HLA-DR, CD80 and CD86 expression. The maturation effect of MS CSF and LM CSF could be blocked by anti-TNF-alpha MoAb or recombinant human IL-10. moDC cultured with BM CSF either remained immature or turned into CD14+ macrophage-like cells and were relatively inefficient at inducing T cell responses in vitro. In contrast, moDC cultured with LM CSF induced strong Th1 responses. Both BM CSF and LM CSF contained IFN-gamma, a cytokine that augments IL-12 production by moDC and hence should confer an ability to induce a Th1 response. However, BM CSF also contained high levels of IL-10, which could antagonize the effects of IFN-gamma on moDC. moDC cultured with MS CSF induced a higher production of IFN-gamma from T cells compared to moDC cultured with NIND CSF or BM CSF. In summary, soluble factors present in the CSF may influence the phenotype and functions of meningeal, choroid plexus and CSF DC which, in turn, may have an impact on the character of intrathecal T cell responses.
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PMID:Cerebrospinal fluid affects phenotype and functions of myeloid dendritic cells. 1198 31

Bacterial meningitis is the serious infection of the central nervous system (CNS), and stimulated by bacteria inflammatory host response has crucial role in its pathogenesis. The most important elements of this response are cytokines, especially tumor necrosis factor (TNF-alpha), interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6), interleukin-8 (IL-8), and interleukin-10 (IL-10), which have antiinflammatory activity. Production of cytokines in the CNS triggers a cascade of inflammatory mediators. Better understanding of mechanisms which take place during the course of the bacterial meningitis can be useful in differential diagnosis, prognosis and treatment of this disease. Investigations on the role of cytokines in the bacterial meningitis, have great therapeutic implications, and can result in introduction to the treatment antiinflammatory drugs, which can help to reduce mortality rate and number of complications.
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PMID:[The role of cytokines in bacterial meningitis]. 1204 Oct 21

Bacterial meningitis causes neuronal apoptosis in the hippocampal dentate gyrus, which is associated with learning and memory impairments after cured disease. The execution of the apoptotic program involves pathways that converge on activation of caspase-3, which is required for morphological changes associated with apoptosis. Here, the time course and the role of caspase-3 in neuronal apoptosis was assessed in an infant rat model of pneumococcal meningitis. During clinically asymptotic meningitis (0-12 h after infection), only minor apoptotic damage to the dentate gyrus was observed, while the acute phase (18-24 h) was characterized by a massive increase of apoptotic cells, which peaked at 36 h. In the subacute phase of the disease (36-72 h), the number of apoptotic cells decreased to control levels. Enzymatic caspase-3 activity was significantly increased in hippocampal tissue of infected animals compared to controls at 22 h. The activated enzyme was localized to immature cells of the dentate gyrus, and in vivo activity was evidenced by cleavage of the amyloid-beta precursor protein. Intracisternal administration of the caspase-3-specific inhibitor Ac-DEVD-CHO significantly reduced apoptosis in the hippocampal dentate gyrus. In contrast to a study where the decrease of hippocampal apoptosis after administration of a pan-caspase inhibitor was due to downmodulation of the inflammatory response, our data demonstrate that specific inhibition of caspase-3 did not affect inflammation assessed by TNF-alpha and IL-1beta concentrations in the cerebrospinal fluid space. Taken together, the present results identify caspase-3 as a key effector of neuronal apoptosis in pneumococcal meningitis.
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PMID:Caspase-3 mediates hippocampal apoptosis in pneumococcal meningitis. 1267 51

We evaluated the efficacy of non-competitive N-methyl-D-aspartate receptor antagonist MK-801 (dizocilpine) as an adjuvant therapy in experimental neonal bacterial meningitis. Meningitis was induced by injecting 10(6) colony forming units of Escherichia coli into the cisterna magna. MK-801 3 mg/kg was given as a bolus intravenous injection, 30 min before the induction of meningitis. MK-801 did not down-modulate the inflammatory parameters, such as increased intracranial pressure, cerebrospinal fluid (CSF) leukocytosis, increased lactate and TNF-alpha levels in the CSF, and hypoglycorrhachia observed in the meningitis group. MK-801 did not significantly attenuate the elevated glutamate concentration in the CSF. However, MK-801 showed some neuroprotective effects as evidenced by significant attenuation of cerebral lipid peroxidation products (conjugated dienes) and increase of brain high-energy phosphate compounds (ATP and PCr). Improvement in cerebral cortical cell membrane Na+, K+ -ATPase activity did not reach a statistical significance. These results suggest that MK-801 was effective in ameliorating brain injury in neonatal bacterial meningitis, although it failed to attenuate the inflammatory responses.
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PMID:Effects of MK-801 (dizocilpine) on brain cell membrane function and energy metabolism in experimental Escherichia coli meningitis in the newborn piglet. 1269 22


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