RESUMEN
Liver kinase B1 (LKB1) is a ubiquitously expressed kinase involved in the regulation of cell metabolism, growth, and inflammatory activation. We previously reported that a single nucleotide polymorphism in the gene encoding LKB1 is a risk factor for multiple sclerosis (MS). Since astrocyte activation and metabolic function have important roles in regulating neuroinflammation and neuropathology, we examined the serine/threonine kinase LKB1 in astrocytes in a chronic experimental autoimmune encephalomyelitis mouse model of MS. To reduce LKB1, a heterozygous astrocyte-selective conditional knockout (het-cKO) model was used. While disease incidence was similar, disease severity was worsened in het-cKO mice. RNAseq analysis identified Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways enriched in het-cKO mice relating to mitochondrial function, confirmed by alterations in mitochondrial complex proteins and reductions in mRNAs related to astrocyte metabolism. Enriched pathways included major histocompatibility class II genes, confirmed by increases in MHCII protein in spinal cord and cerebellum of het-cKO mice. We observed increased numbers of CD4+ Th17 cells and increased neuronal damage in spinal cords of het-cKO mice, associated with reduced expression of choline acetyltransferase, accumulation of immunoglobulin-γ, and reduced expression of factors involved in motor neuron survival. In vitro, LKB1-deficient astrocytes showed reduced metabolic function and increased inflammatory activation. These data suggest that metabolic dysfunction in astrocytes, in this case due to LKB1 deficiency, can exacerbate demyelinating disease by loss of metabolic support and increase in the inflammatory environment.
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Astrocitos/metabolismo , Esclerosis Múltiple/metabolismo , Vaina de Mielina/metabolismo , Proteínas Serina-Treonina Quinasas/deficiencia , Proteínas Quinasas Activadas por AMP , Animales , Diferenciación Celular/genética , Supervivencia Celular/fisiología , Modelos Animales de Enfermedad , Encefalomielitis Autoinmune Experimental/genética , Encefalomielitis Autoinmune Experimental/patología , Hígado/metabolismo , Ratones Noqueados , Esclerosis Múltiple/genética , Médula Espinal/patologíaRESUMEN
At the 2017 joint meeting of the International Society for Neurochemistry (ISN) and the European Society for Neurochemistry, 150 years of neurochemistry - the 50th anniversary of ISN, 40 years of European Society for Neurochemistry, and 60 years of the Journal of Neurochemistry (JNC) - was celebrated with a historical symposium that explored the foundations of neurochemical societies, key international figures in the discipline of neurochemistry, and the pre-eminent role of the JNC. The foundations of neurochemistry were laid in Europe, notably France and Germany, in the late 18th and early 19th centuries. Neurochemists in the United Kingdom made globally relevant contributions before and after the Second World War, and Swedish contributions were especially prominent in the 1950s and 1960s. As neurochemistry is a truly international branch of neuroscience, the important contributions of neurochemists in the Americas and the Asia-Pacific were also recognized, as were the seminal roles of the American, Asia-Pacific, and Japanese Societies of Neurochemistry. Although ISN was only formed in 1967, earlier international meetings in Europe and the Americas reflected the growing recognition of the importance of chemistry and biochemistry for understanding and responding to the pathophysiology of clinical conditions and diseases of the central and peripheral nervous systems. JNC was first published in 1956, but the ISN only assumed complete ownership of the journal under tempestuous circumstances in 1970. The ISN-JNC interface and the sterling work of the JNC Editors has meant that the income generated by the journal has allowed the ISN Council to implement diverse programs for supporting neurochemistry internationally, including sustaining regional neurochemical societies, and supporting neurochemists in the developing world and schools of neurochemistry.
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Neuroquímica/historia , Sociedades Científicas/historia , Américas , Animales , Asia , Europa (Continente) , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Cooperación Internacional/historia , Neurotransmisores/historiaRESUMEN
Extracellular vesicles (EVs) are membrane nanovesicles of diverse sizes secreted by different cell types and are involved in intercellular communication. EVs shuttle proteins, nucleic acids, and lipids that reflect their cellular origin and could mediate their biological function in recipient cells. EVs circulate in biological fluids and are considered as potential biomarkers that could be used to analyze and characterize disease development, course and response to treatment. EVs exhibit specific distribution of glycolipids and membrane organization, but little is known about the biological significance of this distribution or how it could contribute to pathological conditions such as multiple sclerosis (MS). We provide the first description of sulfatide composition in plasma-derived EVs by ultra-high-performance liquid chromatography tandem mass spectrometry. We found that EVs of different sizes showed C16:0 sulfatide but no detectable levels of C18:0, C24:0, or C24:1 sulfatide species. Small EVs isolated at 100,000 × g-enriched in exosomes-from plasma of patients with MS showed a significant increase of C16:0 sulfatide compared with healthy controls. Nanoparticle tracking analysis showed that the particle size distribution in MS plasma was significantly different compared with healthy controls. Characterization of small EVs isolated from MS plasma showed similar protein content and similar levels of exosomal markers (Alix, Rab-5B) and vesicular marker MHC class I (major histocompatibility complex class I) compared with healthy controls. Our findings indicate that C16:0 sulfatide associated with small EVs is a candidate biomarker for MS that could potentially reflect pathological changes associated with this disease and/or the effects of its treatment. © 2016 Wiley Periodicals, Inc.
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Vesículas Citoplasmáticas/metabolismo , Vesículas Extracelulares/metabolismo , Esclerosis Múltiple/metabolismo , Sulfoglicoesfingolípidos/metabolismo , Adulto , Biomarcadores , Cromatografía Líquida de Alta Presión , Vesículas Citoplasmáticas/química , Vesículas Extracelulares/química , Femenino , Genes MHC Clase I , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/sangre , Nanopartículas/química , Nanopartículas/metabolismo , Tamaño de la Partícula , Sulfoglicoesfingolípidos/análisis , Sulfoglicoesfingolípidos/sangre , Espectrometría de Masas en Tándem , Adulto JovenRESUMEN
The most commonly used immunogen to induce experimental autoimmune encephalomyelitis is MOG35-55 , a 21-residue peptide derived from myelin oligodendrocyte glycoprotein (MOG). In most studies, mice exhibit a chronic disease; however, in some studies mice show a transient disease. One variable that is not often controlled for is the peptide fraction of the purified MOG material, which can vary from less than 50% to over 90%, with the remainder of mass primarily comprised of the counter ion used for peptide purification. We compared the development of clinical signs in female C57Bl6 mice immunized with two commercially available MOG35-55 peptides of similar purity but different peptide fraction (MOG-A being 45%; MOG-B being 72%). A single immunization with MOG-A induced a chronic disease course with some recovery at later stages, whereas immunization with MOG-B induced a similar course of disease but with significantly lower average clinical scores despite a higher peptide content. The addition of a booster immunization significantly increased clinical severity with both preparations, and significantly reduced the average day of onset using MOG-A. To determine if the counter ion could influence disease, we compared MOG-B-containing trifluoroacetate with MOG-B-containing acetate. Although disease incidence and severity were similar, the average day of disease onset occurred approximately 5 days earlier with the use of MOG-B-containing trifluoroacetate. These results demonstrate that differences in peptide fraction influence the course of encephalomyelitis disease, which may be due in part to the levels of counter ions present in the purified material. These findings underscore the fact that a knowledge of peptide fraction is as critical as knowledge of peptide purity when using peptides from different sources.
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Acetatos/farmacología , Autoantígenos/aislamiento & purificación , Fraccionamiento Químico/métodos , Encefalomielitis Autoinmune Experimental/inducido químicamente , Glicoproteína Mielina-Oligodendrócito/aislamiento & purificación , Ácido Trifluoroacético/farmacología , Vacunas Sintéticas/aislamiento & purificación , Acetatos/administración & dosificación , Acetatos/análisis , Acetatos/toxicidad , Secuencia de Aminoácidos , Animales , Autoantígenos/administración & dosificación , Autoantígenos/química , Autoantígenos/toxicidad , Progresión de la Enfermedad , Relación Dosis-Respuesta Inmunológica , Contaminación de Medicamentos , Encefalomielitis Autoinmune Experimental/inmunología , Femenino , Inmunización/métodos , Inmunización Secundaria , Ratones , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Glicoproteína Mielina-Oligodendrócito/administración & dosificación , Glicoproteína Mielina-Oligodendrócito/química , Glicoproteína Mielina-Oligodendrócito/toxicidad , Fragmentos de Péptidos/administración & dosificación , Fragmentos de Péptidos/química , Fragmentos de Péptidos/aislamiento & purificación , Fragmentos de Péptidos/toxicidad , Índice de Severidad de la Enfermedad , Factores de Tiempo , Ácido Trifluoroacético/análisis , Ácido Trifluoroacético/toxicidad , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/química , Vacunas Sintéticas/toxicidadRESUMEN
Currently, the genetic variants strongly associated with risk for Multiple Sclerosis (MS) are located in the Major Histocompatibility Complex. This includes DRB1*15:01 and DRB1*15:03 alleles at the HLA-DRB1 locus, the latter restricted to African populations; the DQB1*06:02 allele at the HLA-DQB1 locus which is in high linkage disequilibrium (LD) with DRB1*15:01; and protective allele A*02:01 at the HLA-A locus. HLA allele identification is facilitated by co-inherited ('tag') single nucleotide polymorphisms (SNPs); however, SNP validation is not typically done outside of the discovery population. We examined 19 SNPs reported to be in high LD with these alleles in 2,502 healthy subjects included in the 1000 Genomes panel having typed HLA data. Examination of 3 indices (LD R2 values, sensitivity and specificity, minor allele frequency) revealed few SNPs with high tagging performance. All SNPs examined that tag DRB1*15:01 were in perfect LD in the British population; three showed high tagging performance in 4 of the 5 European, and 2 of the 4 American populations. For DQB1*06:02, with no previously validated tag SNPs, we show that rs3135388 has high tagging performance in one South Asian, one American, and one European population. We identify for the first time that rs2844821 has high tagging performance for A*02:01 in 5 of 7 African populations including African Americans, and 4 of the 5 European populations. These results provide a basis for selecting SNPs with high tagging performance to assess HLA alleles across diverse populations, for MS risk as well as for other diseases and conditions.
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Alelos , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Desequilibrio de Ligamiento , Esclerosis Múltiple , Polimorfismo de Nucleótido Simple , Humanos , Esclerosis Múltiple/genética , Cadenas beta de HLA-DQ/genética , Cadenas HLA-DRB1/genética , Genoma Humano , RiesgoRESUMEN
Previous studies showed that depleting Liver Kinase-B1 (LKB1) from astrocytes increased inflammatory factors lipocalin-2 (LCN2) and osteopontin (OPN) in EAE. A single nucleotide polymorphism (SNP) in STK11 (encoding LKB1) is a risk factor for MS, suggesting increased LCN2 or OPN contributes to risk. Serum LCN2 and OPN levels in African American female MS patients were higher than healthy controls, and while levels increased with disease duration in cases without the SNP, levels decreased with duration in cases with the SNP. Increased MS risk associated with the STK11 SNP may be due to higher LCN2 or OPN levels at early times.
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Quinasas de la Proteína-Quinasa Activada por el AMP/genética , Lipocalina 2/sangre , Esclerosis Múltiple Recurrente-Remitente/sangre , Esclerosis Múltiple Recurrente-Remitente/genética , Adulto , Negro o Afroamericano/genética , Biomarcadores/sangre , Progresión de la Enfermedad , Femenino , Predisposición Genética a la Enfermedad/genética , Humanos , Persona de Mediana Edad , Osteopontina/sangre , Polimorfismo de Nucleótido SimpleRESUMEN
BACKGROUND: Multiple sclerosis (MS) is the most common demyelinating disease and characterized by immunological changes. Oligoclonal bands of IgG in CSF not seen in corresponding serum have been used for many years as part of the diagnostic criteria. However, considerably less is known about the role of IgM, despite several studies showing marked changes to IgM metabolism in MS. Bands of oligoclonal IgM (o-IgM) are more difficult to determine than oligoclonal IgG, thus limiting their study, and there is no agreement as to whether o-IgM in CSF should be part of the clinical work-up of MS. Nevertheless, there is a possibility that such bands might provide a prognostic marker if a cut-off could be established. MATERIALS AND METHODS: In this pilot study, paired samples of CSF and serum from 37 patients with relapsing-remitting MS (RRMS) and 57 controls with no subsequent signs of neurological disease were analysed for total IgM, and bands of o-IgM were visualised by isoelectric focusing and western blot. Patient records were used to compare mean changes in Expanded Disability Status Scale (EDSS) over a maximum of 17 years. RESULTS: None of the controls displayed extra o-IgM in CSF compared to corresponding serum, whereas additional o-IgM band(s) were seen in CSF in most patient samples (70%). After five years of disease, there was a significant difference in the EDSS between patients with no extra o-IgM compared to patients with at least one extra o-IgM band. This difference increased over time. If a cut-off of two or more extra bands of o-IgM in CSF was applied, this difference was not found. CONCLUSION: These exploratory data suggest that o-IgM support the prognostic potential for RRMS, and though tentative, the occurrence of any bands of o-IgM restricted to CSF seems to result in poorer prognosis. Despite the small size of the groups, the data infer that the absence of CSF-restricted o-IgM is good news for the patient. The results need to be reproduced in a more comprehensive study.
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Esclerosis Múltiple Recurrente-Remitente , Esclerosis Múltiple , Humanos , Bandas Oligoclonales , Esclerosis Múltiple Recurrente-Remitente/diagnóstico , Estudios Retrospectivos , Esclerosis Múltiple/diagnóstico , Proyectos PilotoRESUMEN
Although over 20 disease modifying therapies are approved to treat Multiple Sclerosis (MS), these do not increase remyelination of demyelinated axons or mitigate axon damage. Previous studies showed that lanthionine ketenamine ethyl ester (LKE) reduces clinical signs in the experimental autoimmune encephalomyelitis (EAE) mouse model of MS and increased maturation of oligodendrocyte (OL) progenitor cells (OPCs) in vitro. In the current study, we used the cuprizone (CPZ) demyelination model of MS to test if LKE could increase remyelination. The corpus callosum (CC) and somatosensory cortex was examined by immunohistochemistry (IHC), electron microscopy and for mRNA expression changes in mice provided 5 weeks of CPZ diet followed by 2 weeks of normal diet in the presence of LKE or vehicle. A significant increase in the number of myelinated axons, and increased myelin thickness was observed in the CC of LKE-treated groups compared to vehicle-treated groups. LKE also increased myelin basic protein and proteolipid protein expression in the CC and cortex, and increased the number of mature OLs in the cortex. In contrast, LKE did not increase the percentage of proliferating OPCs suggesting effects on OPC survival and differentiation but not proliferation. The effects of LKE on OL maturation and remyelination were supported by similar changes in their relative mRNA levels. Interestingly, LKE did not have significant effects on GFAP or Iba1 immunostaining or mRNA levels. These findings suggest that remyelinating actions of LKE can potentially be formulated to induce remyelination in neurological diseases associated with demyelination including MS.
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Encefalomielitis Autoinmune Experimental , Esclerosis Múltiple , Remielinización , Aminoácidos Sulfúricos , Animales , Cuprizona/toxicidad , Modelos Animales de Enfermedad , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Ésteres/farmacología , Ratones , Esclerosis Múltiple/tratamiento farmacológico , ARN MensajeroRESUMEN
Myelin repair is inhibited in multiple sclerosis (MS), ultimately leading to axonal damage and disability. We aimed to understand the transcriptional mechanisms of regeneration in primary human oligodendrocyte cultures isolated from white matter of medically intractable epilepsy patients. Cultures at isolation contained 84% mature oligodendrocytes and 16% oligodendrocyte progenitor cells (OPC). The two populations showed a protracted regeneration of membranes expressing myelin proteins after 2-3 weeks in culture, and were kept long-term to study membranes maintenance. We profiled by quantitative PCR (qPCR) the sequential mRNA expression of transcription factors Olig1, Olig2, Nkx2.2, Sox10, PPARδ, PPARγ, cyclic nucleotide phosphodiesterase (CNP), myelin basic protein (MBP), myelin-associated glycoprotein (MAG) and myelin oligodendrocyte glycoprotein (MOG). In summary, Olig1 was not expressed in freshly isolated oligodendrocytes, but was expressed from the beginning of process extension until membranes maintenance. In contrast, Olig2 expression was restricted to isolation and during membranes production. We show for the first time PPARδ expression and absence of PPARγ in human oligodendrocytes. Nkx2.2, Sox10, PPARδ, CNP, MBP and MOG messengers were expressed at any time, while MAG messenger was expressed at mature stage only. Myelin proteins CNP, MBP, MAG, and MOG were confirmed by immunocytochemistry. Our findings point to different roles of Olig1 and Olig2 in regeneration of cultured adult human oligodendrocytes. Noticeably, the transcriptional profiles found in cultured neonatal rodent OPC are different. More studies are necessary to elucidate myelin repair in the adult human brain.
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Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Diferenciación Celular/genética , Proteínas del Tejido Nervioso/genética , Oligodendroglía/metabolismo , Adolescente , Animales , Animales Recién Nacidos , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/biosíntesis , Membrana Celular/genética , Membrana Celular/metabolismo , Células Cultivadas , Niño , Epilepsia/genética , Epilepsia/metabolismo , Epilepsia/patología , Femenino , Proteína Homeobox Nkx-2.2 , Proteínas de Homeodominio , Humanos , Masculino , Ratones , Regeneración Nerviosa/genética , Proteínas del Tejido Nervioso/biosíntesis , Proteínas Nucleares , Factor de Transcripción 2 de los Oligodendrocitos , Oligodendroglía/citología , Factores de Transcripción , Adulto JovenRESUMEN
BACKGROUND: We previously reported that the single nucleotide polymorphism (SNP) rs9282860 in serine threonine kinase 11 (STK11) gene which codes for liver kinase B1 (LKB1) has higher prevalence in White relapsing-remitting multiple sclerosis (RRMS) patients than controls. However it is not known if this SNP is a risk factor for MS in other populations. METHODS: We assessed the prevalence of the STK11 SNP in samples collected from African American (AA) persons with MS (PwMS) and controls at multiple Veterans Affairs (VA) Medical Centers and from a network of academic MS centers. Genotyping was carried out using a specific Taqman assay. Comparisons of SNP frequencies were made using Fisher's exact test to determine significance and odds ratios. Group means were compared by appropriate t-tests based on normality and variance using SPSS V27. RESULTS: There were no significant differences in average age at first symptom onset, age at diagnosis, disease duration, or disease severity between RRMS patients recruited from VAMCs versus non-VAMCs. The SNP was more prevalent in AA than White PwMS, however only in secondary progressive MS (SPMS) patients was that difference statistically significant. AA SPMS patients had higher STK11 SNP prevalence than controls; and in that cohort the SNP was associated with older age at symptom onset and at diagnosis. CONCLUSIONS: The results suggest that the STK11 SNP represents a risk factor for SPMS in AA patients, and can influence both early (onset) and later (conversion to SPMSS) events.
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Esclerosis Múltiple Crónica Progresiva , Esclerosis Múltiple Recurrente-Remitente , Esclerosis Múltiple , Negro o Afroamericano/genética , Anciano , Humanos , Hígado , Esclerosis Múltiple/epidemiología , Esclerosis Múltiple/genética , Esclerosis Múltiple Recurrente-Remitente/epidemiología , Esclerosis Múltiple Recurrente-Remitente/genética , Polimorfismo de Nucleótido Simple/genética , Proteínas Serina-Treonina Quinasas/genéticaRESUMEN
The importance and essential functions of glial cells in the nervous system are now beginning to be understood and appreciated. Glial cell lines have been instrumental in the elucidation of many of these properties. In this Overview, the origin and properties of most of the existing cell lines for the major glial types: oligodendroglia, astroglia, microglia and Schwann cells, are documented. Particular emphasis is given to the culture conditions for each cell line and the degree to which the line can differentiate in vitro and in vivo. The major molecular markers for each glial cell lines are indicated. Finally, methods by which the glial cell lines have been developed are noted and the future directions of glial cell line research are discussed.
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Neuroglía/citología , Línea Celular , HumanosRESUMEN
In contrast to gut, the oral microbiome of MS patients has not been characterized. Deep sequencing of saliva DNA from a pair of monozygotic twins (MSF1 with relapsing remitting MS; MSF2 with clinically isolated syndrome) identified 2036 bacterial species. Relative abundances of 3 phyla were higher, and 3 lower in MSF1 versus MSF2. Species diversity was greater in MSF2, and 20 abundant species differed at least 2-fold. Pathway analysis identified 116 functional hierarchies differing 50% or more. Although limited to one pair of twins, our data suggests that oral microbiome analysis may be useful for diagnosis or monitoring therapeutic efficacy.
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Enfermedades Desmielinizantes/microbiología , Boca/microbiología , Esclerosis Múltiple Recurrente-Remitente/microbiología , Adulto , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Metagenoma , Microbiota , Gemelos MonocigóticosRESUMEN
We previously showed LKE (lanthionine ketimine ester) reduces disease in the EAE model of multiple sclerosis, however whether LKE affects oligodendrocytes (OLGs) was not tested. In OLG progenitor cells (OPCs), LKE increased process number and area, but not PDGF-receptor-alpha expressing cells. In contrast, PDGF increased OPC numbers, but reduced process number and area. LKE increased collapsin response mediator protein-2 (CRMP2) expression, an LKE target, and CRMP2-expressing OLGs expressed myelin basic protein. LKE increased markers of OPC maturation, while PDGF, but not LKE, increased Sox2 expression. Our findings suggest that effects on OPCs may contribute to LKE beneficial actions in EAE.
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Aminoácidos Sulfúricos/farmacología , Péptidos y Proteínas de Señalización Intercelular/agonistas , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Proteínas del Tejido Nervioso/agonistas , Proteínas del Tejido Nervioso/metabolismo , Células Precursoras de Oligodendrocitos/efectos de los fármacos , Células Precursoras de Oligodendrocitos/metabolismo , Animales , Animales Recién Nacidos , Células Cultivadas , Femenino , Embarazo , Ratas , Ratas Sprague-DawleyRESUMEN
Oligodendrocytes (OLG) have more complex interactions with nitric oxide (NO) than initially suspected. Historically, OLG were seen only as targets of high NO levels released from other cells. Expression of nitric oxide synthase type II (NOS-2) in primary cultures of OLGs stimulated by cytokines led to controversy due to the presence of small numbers of microglia, cells also inducible for NOS-2 expression. The present review summarizes the findings that immature OLG express NOS-2, but that they do not in their most mature stage in culture as membrane sheet-bearing cells. This raises questions about the regulation of NOS-2 expression in OLG. Additionally, novel data are presented on NOS-3 expression in cultured OLG. If confirmed in vivo, this finding suggests that constitutive NOS-3 expression may play a key role in OLG injury due to its activation by calcium, in interaction with pathways mediating glutamate toxicity. The authors discuss in vivo NO levels to place in vitro findings in context, and compare OLG sensitivity to NO with that of other brain cells. Lastly, the multiple interactions of NO are considered with regard to glutamate cytotoxicity, the antioxidant glutathione, mitochondrial function, and myelin architecture.
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Isoenzimas/metabolismo , Óxido Nítrico Sintasa/metabolismo , Óxido Nítrico/toxicidad , Oligodendroglía/efectos de los fármacos , Oligodendroglía/enzimología , Animales , Calcio/metabolismo , Muerte Celular , Células Cultivadas , Humanos , Isoenzimas/genética , Mitocondrias/metabolismo , Neuronas/citología , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Óxido Nítrico Sintasa/genética , Oligodendroglía/citologíaRESUMEN
Superwarfarins were developed following the emergence of warfarin resistance in rodents. Compared to warfarin, superwarfarins have much longer half-lives and stronger affinity to vitamin K epoxide reductase and therefore can cause death in warfarin-resistant rodents. By the mid-1970s, the superwarfarins brodifacoum and difenacoum were the most widely used rodenticides throughout the world. Unfortunately, increased use was accompanied by a rise in accidental poisonings, reaching >16,000 per year in the United States. Risk of exposure has become a concern since large quantities, up to hundreds of kilograms of rodent bait, are applied by aerial dispersion over regions with rodent infestations. Reports of intentional use of superwarfarins in civilian and military scenarios raise the specter of larger incidents or mass casualties. Unlike warfarin overdose, for which 1-2 days of treatment with vitamin K is effective, treatment of superwarfarin poisoning with vitamin K is limited by extremely high cost and can require daily treatment for a year or longer. Furthermore, superwarfarins have actions that are independent of their anticoagulant effects, including both vitamin K-dependent and -independent effects, which are not mitigated by vitamin K therapy. In this review, we summarize superwarfarin development, biology and pathophysiology, their threat as weapons, and possible therapeutic approaches.
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Warfarina/efectos adversos , Warfarina/análisis , Animales , Anticoagulantes/efectos adversos , Anticoagulantes/análisis , Anticoagulantes/química , Biomarcadores/análisis , Exposición a Riesgos Ambientales/análisis , Humanos , Riñón/efectos de los fármacos , Riñón/patología , Sistema Nervioso/efectos de los fármacos , Sistema Nervioso/patología , Warfarina/química , Warfarina/envenenamientoRESUMEN
Multiple sclerosis (MS) is characterized by inflammation within the CNS. This inflammatory response is associated with production of nitric oxide (NO) and NO-related species that nitrosylate thiols. We postulated that MS patients would exhibit an antibody (Ab) response directed against proteins containing S-nitrosocysteine (SNO-cysteine) and showed that anti-NO-cysteine Abs of the IgM isotype are in fact present in the sera of some MS patients (Boullerne et al., 1995). We report here the presence of a seemingly identical Ab response directed against SNO-cysteine in an acute model of MS, experimental autoimmune encephalomyelitis (EAE) induced in Lewis rats with the 68-84 peptide of guinea pig myelin basic protein (MBP(68-84)). Serum levels of anti-SNO-cysteine Abs peaked 1 week before the onset of clinical signs and well before the appearance of anti-MBP(68-84) Abs. The anti-SNO-cysteine Ab peak titer correlated with the extent of subsequent CNS demyelination, suggesting a link between Ab level and CNS lesion formation. In relapsing-remitting MS patients, we found elevated anti-SNO-cysteine Ab at times of relapse and normal values in most patients judged to be in remission. Two-thirds of patients with secondary progressive MS had elevated anti-SNO-cysteine Ab levels, including those receiving interferon beta-1b. The data show that a rise in circulating anti-SNO-cysteine Ab levels precedes onset of EAE. Anti-SNO-cysteine Abs are also elevated at times of MS attacks and in progressive disease, suggesting a possible role for these Abs, measurable in blood, as a biological marker for clinical activity.
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Autoanticuerpos/sangre , Cisteína/análogos & derivados , Cisteína/inmunología , Enfermedades Desmielinizantes/diagnóstico , Encefalomielitis Autoinmune Experimental/sangre , Esclerosis Múltiple/sangre , S-Nitrosotioles/inmunología , Animales , Especificidad de Anticuerpos , Autoanticuerpos/líquido cefalorraquídeo , Autoanticuerpos/farmacología , Biomarcadores/sangre , Cisteína/antagonistas & inhibidores , Enfermedades Desmielinizantes/sangre , Enfermedades Desmielinizantes/etiología , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Encefalomielitis Autoinmune Experimental/complicaciones , Encefalomielitis Autoinmune Experimental/inmunología , Encefalomielitis Autoinmune Experimental/patología , Femenino , Humanos , Inmunoglobulina M/sangre , Esclerosis Múltiple/diagnóstico , Esclerosis Múltiple/inmunología , Proteína Básica de Mielina/inmunología , Compuestos Nitrosos , Fragmentos de Péptidos/inmunología , Valor Predictivo de las Pruebas , Ratas , Ratas Endogámicas Lew , Recurrencia , Remisión Espontánea , S-Nitrosotioles/antagonistas & inhibidores , Albúmina Sérica Bovina/inmunología , Médula Espinal/patologíaRESUMEN
We identified a family in which five siblings were diagnosed with multiple sclerosis (MS) or clinically isolated syndrome. Several women in the maternal lineage have comorbidities typically associated with Peutz Jeghers Syndrome, a rare autosomal-dominant disease caused by mutations in the serine-threonine-kinase 11 (STK11) gene, which encodes liver kinase B1. Sequence analysis of DNA from one sibling identified a single-nucleotide polymorphism (SNP) within STK11 intron 5. This SNP (dbSNP ID: rs9282860) was identified by TaqMan polymerase chain reaction (PCR) assays in DNA samples available from two other siblings. Further screening was carried out in samples from 654 relapsing-remitting MS patients, 100 primary progressive MS patients, and 661 controls. The STK11-SNP has increased frequency in all female patients versus controls (odds ratio = 1.66, 95% CI = 1.05, 2.64, p = .032). The STK11-SNP was not associated with disease duration or onset; however, it was significantly associated with reduced severity (assessed by MS severity scores), with the lowest scores in patients who also harbored the HLA-DRB1*1501 allele. In vitro studies showed that peripheral blood mononuclear cells from members of the family were more sensitive to the mitochondrial inhibitor metformin than cells from MS patients with the major STK11 allele. The increased association of SNP rs9282860 in women with MS defines this variant as a genetic risk factor. The lower disease severity observed in the context of HLA-DRB1*1501 combined with limited in vitro studies raises the provocative possibility that cells harboring the STK11-SNP could be targeted by drugs which increase metabolic stress.
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Predisposición Genética a la Enfermedad/genética , Esclerosis Múltiple/genética , Polimorfismo de Nucleótido Simple/genética , Proteínas Serina-Treonina Quinasas/genética , Quinasas de la Proteína-Quinasa Activada por el AMP , Adulto , Salud de la Familia , Femenino , Estudios de Asociación Genética , Cadenas HLA-DRB1/genética , Humanos , Leucocitos Mononucleares , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/epidemiología , Factores de RiesgoRESUMEN
BACKGROUND: Under pathological conditions, microglia produce proinflammatory mediators which contribute to neurologic damage, and whose levels can be modulated by endogenous factors including neurotransmitters such as norepinephrine (NE). We investigated the ability of NE to suppress microglial activation, in particular its effects on induction and activity of the inducible form of nitric oxide synthase (NOS2) and the possible role that IL-1beta plays in that response. METHODS: Rat cortical microglia were stimulated with bacterial lipopolysaccharide (LPS) to induce NOS2 expression (assessed by nitrite and nitrate accumulation, NO production, and NOS2 mRNA levels) and IL-1beta release (assessed by ELISA). Effects of NE were examined by co-incubating cells with different concentrations of NE, adrenergic receptor agonists and antagonists, cAMP analogs, and protein kinase (PK) A and adenylate cyclase (AC) inhibitors. Effects on the NFkappaB:IkappaB pathway were examined by using selective a NFkappaB inhibitor and measuring IkappaBalpha protein levels by western blots. A role for IL-1beta in NOS2 induction was tested by examining effects of caspase-1 inhibitors and using caspase-1 deficient cells. RESULTS: LPS caused a time-dependent increase in NOS2 mRNA levels and NO production; which was blocked by a selective NFkappaB inhibitor. NE dose-dependently reduced NOS2 expression and NO generation, via activation of beta2-adrenergic receptors (beta2-ARs), and reduced loss of inhibitory IkBalpha protein. NE effects were replicated by dibutyryl-cyclic AMP. However, co-incubation with either PKA or AC inhibitors did not reverse suppressive effects of NE, but instead reduced nitrite production. A role for IL-1beta was suggested since NE potently blocked microglial IL-1beta production. However, incubation with a caspase-1 inhibitor, which reduced IL-1beta levels, had no effect on NO production; incubation with IL-receptor antagonist had biphasic effects on nitrite production; and NE inhibited nitrite production in caspase-1 deficient microglia. CONCLUSIONS: NE reduces microglial NOS2 expression and IL-1beta production, however IL-1beta does not play a critical role in NOS2 induction nor in mediating NE suppressive effects. Changes in magnitude or kinetics of cAMP may modulate NOS2 induction as well as suppression by NE. These results suggest that dysregulation of the central cathecolaminergic system may contribute to detrimental inflammatory responses and brain damage in neurological disease or trauma.