Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0002736 (amyotrophic lateral sclerosis)
 19,048 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Perhaps as many as 25-50% of adult patients and children with acquired immunodeficiency syndrome (AIDS) eventually suffer from neurological manifestations, including dysfunction of cognition, movement, and sensation. How can human immunodeficiency virus type 1 (HIV-1) result in neuronal damage if neurons themselves are for all intents and purposes not infected by the virus? This article reviews a series of experiments leading to a hypothesis that accounts at least in part for the neurotoxicity observed in the brains of AIDS patients. There is growing support for the existence of HIV- or immune-related toxins that lead indirectly to the injury or demise of neurons via a potentially complex web of interactions among macrophages (or microglia), astrocytes, and neurons. HIV-infected monocytoid cells (macrophages, microglia, or monocytes), after interacting with astrocytes, secrete eicosanoids, i.e., arachidonic acid and its metabolites, including platelet-activating factor. Macrophages activated by HIV-1 envelope protein gp120 also appear to release arachidonic acid and its metabolites. In addition, interferon-gamma (IFN-gamma) stimulation of macrophages induces release of the glutamate-like agonist, quinolinate. Furthermore, HIV-infected macrophage production of cytokines, including TNF-alpha and IL1-beta, contributes to astrogliosis. A final common pathway for neuronal susceptibility appears to be operative, similar to that observed in stroke, trauma, epilepsy, neuropathic pain, and several neurodegenerative diseases, possibly including Huntington's disease, Parkinson's disease, and amyotrophic lateral sclerosis. This mechanism involves the activation of voltage-dependent Ca2+ channels and N-methyl-D-aspartate (NMDA) receptor-operated channels, and, therefore, offers hope for future pharmacological intervention. This article focuses on clinically tolerated calcium channel antagonists and NMDA antagonists with the potential for trials in humans with AIDS dementia in the near future.
 ...
PMID:HIV-related neuronal injury. Potential therapeutic intervention with calcium channel antagonists and NMDA antagonists. 799 15

The cause of sporadic amyotrophic lateral sclerosis (SALS) is unknown. We investigated the immune-mediated inflammatory hypothesis of SALS by assaying interleukin-12 (IL-12), interleukin-6 (IL-6) and interferon-gamma (IFN-gamma) in the cerebrospinal fluid (CSF) of patients with SALS. These cytokines were measured in the CSF from patients with SALS (n=11), patients with immune-mediated inflammatory central nervous system or nerve root disorders (n=12), and patients with other neurological diseases (n=15) by high sensitivity sandwich enzyme linked immunosorbent assay (ELISA). All samples were below the assay detection limits of 0.5 pg/ml for IL-12 and 8 pg/ml for IFN-gamma. There was no difference between the groups in the mean concentration of IL-6. There is no evidence in cerebrospinal fluid for induction of a T(H)1 immune response in SALS.
 ...
PMID:Interleukin-12 and interferon-gamma are not detectable in the cerebrospinal fluid of patients with amyotrophic lateral sclerosis. 1520 13

Mutations in the gene coding for the ubiquitous, anti-oxidant enzyme Cu,Zn superoxide dismutase (SOD1) are associated with familial amyotrophic lateral sclerosis (fALS), a fatal disease characterized by selective loss of motor neurons. Expression of a mutant SOD1 typical of fALS patients restricted to either motor neurons or astrocytes is insufficient to generate a pathological phenotype in mouse models, suggesting that a deleterious interplay between different cell types is necessary for the pathogenesis of the disease. In this study, we demonstrate the actual role of a functional cross-talk between glial and neuronal cells expressing fALS mutant G93A-SOD1, where an increase in the production of reactive oxygen species occurs. We show that human glioblastoma cells expressing G93A-SOD1 induce activation of caspase-1, release of cytokines, and activation of apoptotic pathways in cocultured human neuroblastoma cells also expressing G93A-SOD1. Activation of caspase-1 and caspase-3 is observed also in neuroblastoma lines expressing other fALS-SOD1s (G37R, G85R, and I113T) cocultured with glioblastoma lines expressing the corresponding mutant enzymes. These effects are consequent to activation of inflammatory processes in G93A-glioblastoma cells stimulated by cocultured G93A-neuroblastoma. Furthermore, selective death of embryonal spinal motor neurons from G93A-SOD1 transgenic mice is induced by coculture with G93A-glioblastoma and prevented by inhibition of NO synthase. Proinflammatory cytokines, interferon-gamma, and nitric oxide are among the molecular signals exchanged between glial and neuronal cells that generate a functional interplay between the two cell types. This cross-talk may be crucial for the pathogenesis of SOD1-linked fALS but also for the more common sporadic form of the disease, where markers of increased oxidative stress and of glial activation have been found.
 ...
PMID:Cell death in amyotrophic lateral sclerosis: interplay between neuronal and glial cells. 1520 63

Protein aggregation is a pathologic hallmark of familial amyotrophic lateral sclerosis caused by mutations in the Cu, Zn superoxide dismutase gene. Although SOD1-positive aggregates can be cleared by proteasomes, aggregates have been hypothesized to interfere with proteasome activity, leading to a vicious cycle that further enhances aggregate accumulation. To address this issue, we measured proteasome activity in transgenic mice expressing a G93A SOD1 mutation. We find that proteasome activity is induced in the spinal cord of such mice compared to controls but is not altered in uninvolved organs such as liver or spleen. This induction within spinal cord is not related to an overall increase in the total number of proteasome subunits, as evidenced by the steady expression levels of constitutive alpha7 and beta5 subunits. In contrast, we found a marked increase of inducible beta proteasome subunits, LMP2, MECL-1 and LMP7. This induction of immunoproteasome subunits does not occur in all spinal cord cell types but appears limited to astrocytes and microglia. The induction of immunoproteasome subunits in G93A spinal cord organotypic slices treated with TNF-alpha and interferon-gamma suggest that certain cytokines may mediate such responses in vivo. Our results indicate that there is an overall increase in proteasome function in the spinal cords of G93A SOD1 mice that correlates with an induction of immunoproteasomes subunits and a shift toward immunoproteasome composition. These results suggest that increased, rather than decreased, proteasome function is a response of certain cell types to mutant SOD1-induced disease within spinal cord.
 ...
PMID:Non-neuronal induction of immunoproteasome subunits in an ALS model: possible mediation by cytokines. 1624 25

We found comparable levels of tumor necrosis factor (TNF)-alpha, interferon-gamma, interleukin (IL)-2, IL-4, IL-10, and IL-12 in the sera of 22 patients with multifocal motor neuropathy (MMN), 12 with amyotrophic lateral sclerosis (ALS), 12 multiple sclerosis, seven chronic inflammatory demyelinating polyneuropathy, five myasthenia gravis, and 13 healthy controls (NS). TNF-alpha levels, however, were higher in 15 (68%) MMN patients than in any NS. In all but one MMN patient tested, TNF-alpha levels repeatedly, albeit slightly, increased after each intravenous immunoglobulin infusion in parallel with clinical improvement and decreased 3-4 weeks after therapy, while in both ALS patients tested, they decreased or remained unchanged. The possible pathogenetic relevance of serum TNF-alpha modification in MMN remains to be clarified.
 ...
PMID:Circulating levels of cytokines and their modulation by intravenous immunoglobulin in multifocal motor neuropathy. 1651 84

To investigate cytokine/chemokine changes in amyotrophic lateral sclerosis (ALS), we simultaneously measured 16 cytokine/chemokines (interleukin [IL]-1beta, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12 [p70], IL-13, IL-17, interferon-gamma, tumor necrosis factor-alpha, granulocyte colony stimulating factor [G-CSF], macrophage chemoattractant protein-1 [MCP-1], and macrophage inflammatory protein-1beta) in cerebrospinal fluid (CSF) and sera from 37 patients with sporadic ALS and 33 controls using a multiplexed fluorescent bead-based immunoassay. We also conducted immunohistochemical analyses from 8 autopsied ALS cases and 6 nonneurologic disease controls as well as cell culture analyses of relevant cytokines and their receptors. We found that concentrations of G-CSF and MCP-1 were significantly increased in ALS CSF compared with controls. In spinal cords, G-CSF was expressed in reactive astrocytes in ALS cases but not controls, whereas G-CSF receptor expression was significantly decreased in motor neurons of spinal cords from ALS cases. Biologically, G-CSF had a protective effect on the NSC34 cell line under conditions of both oxidative and nutritional stress. We suggested that G-CSF has potentially neuroprotective effects on motor neurons in ALS and that downregulation of its receptor might contribute to ALS pathogenesis. On the other hand, MCP-1 correlated with disease severity, which may aggravate motor neuron damage.
 ...
PMID:Intrathecal upregulation of granulocyte colony stimulating factor and its neuroprotective actions on motor neurons in amyotrophic lateral sclerosis. 1689 15

In amyotrophic lateral sclerosis (ALS), an involvement of the immune system in the degenerative processes has been shown in both humans and the transgenic SOD1-G93A mice. We previously showed that Glatiramer acetate (also known as copolymer-1; COP-1; Copaxone) improves motor function and extends survival times in an inbred strain of ALS mice probably by interacting with pro-inflammatory T(H) lymphocytes. In the course of this study we tested whether these beneficial effects could be reproduced by repeated vaccination of animals with COP-1 without co-administration of complete Freund's adjuvant. In an outbred strain we could not demonstrate a positive effect of COP-1 on survival times, but found a significant improvement of motor performance during the late stage of disease and a moderate decrease of the production of the inflammatory cytokines interferon-gamma and IL-4 by T lymphocytes isolated from the mice's spleen. In conclusion, the effects of COP-1 in the applied hybrid strain displaying a faster disease progression were less pronounced than in the earlier tested inbred strain of ALS mice.
 ...
PMID:Limited effects of glatiramer acetate in the high-copy number hSOD1-G93A mouse model of ALS. 1759 11

The role of cytokines in the pathophysiology of amyotrophic lateral sclerosis (ALS) and its relation to clinical outcome has not been clearly defined. We evaluated tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma) and nitric oxide (NO) levels in the serum of 22 ALS patients and 20 controls. Serum TNF-alpha levels and IFN-gamma levels were significantly (P < 0.001) elevated in ALS patients. We also observed NO levels to be significantly (P < 0.05) increased with respect to normal subjects. We further noticed positive correlation between the duration of ALS and these proinflammatory molecule levels. Exitotoxicity and oxidative stress are known to play a crucial role in the neurodegeneration observed in ALS. Since high levels of TNF-alpha are known to be cytotoxic, it could be that a complex interplay of these effectors may be one of the factors underlying the progression of ALS. This study confirms the involvement of inflammation in ALS and the need to develop surrogate markers to check the progression of this disease.
 ...
PMID:Elevated inflammatory markers in a group of amyotrophic lateral sclerosis patients from northern India. 1824 26

Although significant effects of interferon-gamma (IFN-gamma) on glial cells are well documented, information on the expression level and localization of glial IFN-gamma receptors (IFN-gamma-R) in the human central nervous system (CNS) is sparse. To examine the glial expression of IFN-gamma-R in the human CNS, immunohistochemistry and quantitative analyses were performed on Alzheimer disease hippocampus, Parkinson disease substantia nigra, amyotrophic lateral sclerosis spinal cord and corresponding areas from non-neurological cases. Almost all IFN-gamma-R-positive (IFN-gamma-R(+)) cells corresponded to GFAP-positive (GFAP(+)) astrocytes, while none of IFN-gamma-R(+) cells corresponded to IBA1-positive (IBA1(+)) microglia or MBP-positive (MBP(+)) oligodendrocytes in these neurological cases. We observed a similar pattern of glial IFN-gamma-R expression in non-neurological cases. Also, we quantitatively analyzed the IFN-gamma-R expression by cultured human glial cells using immunocytochemistry and reverse transcription polymerase chain reaction (RT-PCR). In contrast to in vivo results, almost all IFN-gamma-R(+) cells were IBA1(+) in microglial cultures, GFAP(+) in astrocytic cultures and MBP(+) in oligodendrocytic cultures. Moreover, no significant difference in IFN-gamma-R mRNA expression was found for these glial cell types by RT-PCR. These results suggest that the microglial and oligodendrocytic expression levels of IFN-gamma-R are much lower than the astrocytic expression levels in the human CNS in vivo, whereas all three types of glial cells constitutively express IFN-gamma-R when cultured in vitro.
 ...
PMID:Differential expression of interferon-gamma receptor on human glial cells in vivo and in vitro. 2055 27

Astrocytes become activated in degenerative neurological diseases. In order to gain a greater understanding of the inflammatory factors released upon activation, we stimulated adult human astrocytes with interferon-gamma and examined the resultant conditioned medium (CM) for toxicity against differentiated human neuroblastoma SH-SY5Y cells. Cell death was measured by lactate dehydrogenase release assay. We then used various treatments of the media to determine the distribution and nature of the toxic components. Removal of interleukin-6 by a specific antibody reduced the toxicity by 22%. Blockade of proteases with an inhibitor cocktail reduced it by a further 22%. When oxygen-free radical production was blocked with NADPH oxidase inhibitors, the toxicity was reduced by 15.4%. When prostaglandin production was blocked by cyclooxygenase inhibitors, the toxicity of the CM was reduced by 14.5%. When glutamate was removed by treatment with glutamate decarboxylase, the toxicity was reduced by 10.3%. When the inhibitors were added together to the astrocyte culture, the total toxicity of the CM was reduced by 91%. This was in reasonable agreement with the 85.37% total obtained by adding the individual components. The data show that activated astrocytes release a specific combination of neurotoxic compounds. They suggest that effective anti-inflammatory treatment of such neurodegenerative diseases as Alzheimer's disease, Parkinson's disease and Amyotrophic lateral sclerosis could be improved by using an appropriate combination of anti-inflammatory agents instead of relying on any single agent.
 ...
PMID:Neurotoxins released from interferon-gamma-stimulated human astrocytes. 2309 1


1 2 Next >>