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1.
J Clin Med ; 9(2)2020 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-32019214

RESUMEN

BACKGROUND: Saliva, the most readily available body fluid, is the product of genes which are in constant activity throughout life. Measurement of saliva can predict the onset of some diseases years before their accumulation in vulnerable tissues causes clinical signs to appear. The purpose of this study was is to demonstrate current applications of saliva analysis and to predict and prevent disease progression. METHODS: We measured levels of Abeta42, C-reactive proteins (CRPs), and tumornecrosis factors (TNFs) in saliva from both healthy and fatal diseased cases such as cancer, Alzheimer's disease (AD), and coronary heart disease by ELISA-mediated techniques. We also immunostained human tissue sections with antibodies specific to these proteins to demonstrate the data are comparable. RESULTS: We found all the proteins expressed constantly in saliva from healthy controls but increased in diseased cases. This was accompanied by data from immunohistochemistry. It was also found that these proteins wereexpressed in high amounts in some healthy controls, which reflects high risk for the onset of diseases such as AD and heart diseases. CONCLUSIONS: It is concluded that measuring changes in essential gene products in saliva can predict onset of fatal diseases and open the door to effective protection measures, thus preventing premature death.

2.
J Alzheimers Dis ; 62(3): 1219-1222, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29103042

RESUMEN

Alzheimer's disease (AD) is characterized by deposits of amyloid-ß protein (Aß) in brain which become foci of inflammation. Neurons are destroyed by this inflammatory process, leading to the cognitive deficits which define AD clinical onset. Epidemiological studies indicate that nonsteroidal anti-inflammatory drugs (NSAIDs) can ameliorate this destructive process if they are started well before clinical signs develop. Biomarker studies indicate that the disease process starts at least a decade before cognitive deficits appear. This pre-clinical onset explains the NSAID effect. It also opens a window of opportunity for preventive treatment that can be met with a simple diagnostic test. Salivary levels of Aß42 may fulfill that need. They can be measured by a simple ELISA test we have developed using commercially available reagents. By this ELISA test, normal controls, who are not at risk for AD, have levels of Aß42 close to 20 pg/ml. AD cases, as well as high level controls, secrete levels in the range of 40-85 pg/ml. Widespread application of this test to detect high level controls, followed by NSAID consumption, could substantially reduce the prevalence of AD.


Asunto(s)
Enfermedad de Alzheimer/prevención & control , Antiinflamatorios no Esteroideos/uso terapéutico , Fármacos Neuroprotectores/uso terapéutico , Enfermedad de Alzheimer/metabolismo , Humanos
3.
Neurobiol Aging ; 52: 12-22, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28104543

RESUMEN

Complement is the backbone of our innate immune system. It is of ancient evolutionary origin, being traced back to horseshoe crabs 350 million years ago. It consists today of more than 25 proteins which must work together like clockwork to distinguish friend from foe. Self-attack by the complement system can occur whenever it fails to do so. This failure has been reported to occur in an estimated 22 human diseases. A significant number of these are chronic degenerative neurological disorders. In some, there is overwhelming evidence that complement self-attack causes the disease. In many others, it is considered only to contribute to the overall pathology. Finding effective therapeutic agents should be a high priority for medical research. To date, the monoclonal antibody eculizumab is the only approved agent. Molecules under development include other monoclonal antibodies directed at C5, C3, and properdin, various aptamers to C3, and small molecules that are orally available.


Asunto(s)
Activación de Complemento/inmunología , Enfermedades Neurodegenerativas/genética , Enfermedades Neurodegenerativas/inmunología , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/inmunología , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Artritis Reumatoide/genética , Artritis Reumatoide/inmunología , Enfermedad Crónica , Vía Alternativa del Complemento/genética , Vía Clásica del Complemento/genética , Humanos , Degeneración Macular/genética , Degeneración Macular/inmunología , Terapia Molecular Dirigida , Esclerosis Múltiple/genética , Esclerosis Múltiple/inmunología , Enfermedades Neurodegenerativas/tratamiento farmacológico , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/inmunología , Receptores de Complemento
4.
J Alzheimers Dis ; 55(3): 1175-1182, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-27792013

RESUMEN

We have developed a non-invasive method of diagnosing Alzheimer's disease (AD), which can also predict the risk of its future onset. It is based on measuring salivary levels of amyloid-ß protein terminating at position 42 (Aß42). Brain deposits of this peptide are characteristic of AD. Biomarker studies indicate that such brain deposits commence a decade or more prior to clinical onset of the disease. We report here that Aß42 is produced in all peripheral organs tested, thus establishing the generality of its production. We used this information to develop simple and sensitive tests to determine salivary Aß42 levels. The levels were first stabilized by adding thioflavin S as an anti-aggregation agent and sodium azide as an anti-bacterial agent. We then quantitated the Aß42 in a series of samples with ELISA type tests. Control cases showed almost identical levels of salivary Aß42 regardless of sex or age. All AD cases secreted levels of Aß42 more than double those of controls. Individuals at elevated risk of developing AD secreted levels comparable to the AD cases. The results establish that salivary Aß42 levels can be used to diagnose AD as well as to predict the risk of its future onset.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Fragmentos de Péptidos/metabolismo , Saliva/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/genética , Precursor de Proteína beta-Amiloide/genética , Análisis de Varianza , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fragmentos de Péptidos/genética , Escalas de Valoración Psiquiátrica , ARN Mensajero/metabolismo , Adulto Joven
5.
J Alzheimers Dis ; 54(3): 853-857, 2016 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-27716676

RESUMEN

Two basic discoveries spurred research into inflammation as a driving force in the pathogenesis of Alzheimer's disease (AD). The first was the identification of activated microglia in association with the lesions. The second was the discovery that rheumatoid arthritics, who regularly consume anti-inflammatory agents, were relatively spared from the disease. These findings led to an exploration of the inflammatory pathways that were involved in AD pathogenesis. A pivotal advance was the discovery that amyloid-ß protein (Aß) activated the complement system. This focused attention on anti-inflammatories as blockers of complement activation. More than 15 epidemiological studies have since showed a sparing effect of non-steroidal anti-inflammatory drugs (NSAIDs) in AD. A consistent finding has been that the longer the NSAIDs were used prior to clinical diagnosis, the greater the sparing effect. The reason has since emerged from studies of biomarkers such as amyloid-ß (Aß) levels in the cerebrospinal fluid and Aß deposits in brain. They have established that the onset of AD commences at least a decade before cognitive decline permits clinical diagnosis. Such biomarker studies have revealed that a huge window of opportunity exists when application of NSAIDs, other anti-inflammatory agents, or complement activation blockers, could arrest further progress of AD, thus eliminating its manifestation. It can be anticipated that this principle will apply to many other chronic neurodegenerative diseases. Neuroinflammation, discovered in AD more than 30 years ago, has now become a major field of brain research today. Inhibiting it may be the key to successful treatment of many chronic neurological disorders.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Antiinflamatorios/uso terapéutico , Mediadores de Inflamación/metabolismo , Enfermedad de Alzheimer/líquido cefalorraquídeo , Péptidos beta-Amiloides/líquido cefalorraquídeo , Péptidos beta-Amiloides/metabolismo , Animales , Antiinflamatorios/farmacología , Antiinflamatorios no Esteroideos/farmacología , Antiinflamatorios no Esteroideos/uso terapéutico , Biomarcadores/líquido cefalorraquídeo , Biomarcadores/metabolismo , Humanos , Inflamación/líquido cefalorraquídeo , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Mediadores de Inflamación/antagonistas & inhibidores , Mediadores de Inflamación/líquido cefalorraquídeo , Factores de Tiempo
6.
Neurobiol Aging ; 46: 113-23, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27479153

RESUMEN

Epidemiologic studies indicate that coffee consumption reduces the risk of Parkinson's disease and Alzheimer's disease. To determine the factors involved, we examined the protective effects of coffee components. The test involved prevention of neurotoxicity to SH-SY5Y cells that was induced by lipopolysaccharide plus interferon-γ or interferon-γ released from activated microglia and astrocytes. We found that quercetin, flavones, chlorogenic acid, and caffeine protected SH-SY5Y cells from these toxins. They also reduced the release of tumor necrosis factor-α and interleukin-6 from the activated microglia and astrocytes and attenuated the activation of proteins from P38 mitogen-activated protein kinase (MAPK) and nuclear factor kappa light chain enhancer of activated B cells (NFκB). After exposure to toxin containing glial-stimulated conditioned medium, we also found that quercetin reduced oxidative/nitrative damage to DNA, as well as to the lipids and proteins of SH-SY5Y cells. There was a resultant increase in [GSH]i in SH-SY5Y cells. The data indicate that quercetin is the major neuroprotective component in coffee against Parkinson's disease and Alzheimer's disease.


Asunto(s)
Enfermedad de Alzheimer/prevención & control , Café/química , Fármacos Neuroprotectores/farmacología , Enfermedad de Parkinson/prevención & control , Fitoterapia , Quercetina/farmacología , Astrocitos/metabolismo , Cafeína/aislamiento & purificación , Cafeína/farmacología , Células Cultivadas , Ácido Clorogénico/aislamiento & purificación , Ácido Clorogénico/farmacología , Daño del ADN/efectos de los fármacos , Flavonas/aislamiento & purificación , Flavonas/farmacología , Humanos , Interferón gamma/toxicidad , Interleucina-6/metabolismo , Lipopolisacáridos/toxicidad , Microglía/metabolismo , FN-kappa B/metabolismo , Fármacos Neuroprotectores/aislamiento & purificación , Quercetina/aislamiento & purificación , Factor de Necrosis Tumoral alfa/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
7.
J Neuroinflammation ; 13: 32, 2016 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-26856696

RESUMEN

BACKGROUND: Sodium thiosulfate (STS) is an industrial chemical which has also been approved for the treatment of certain rare medical conditions. These include cyanide poisoning and calciphylaxis in hemodialysis patients with end-stage kidney disease. Here, we investigated the anti-inflammatory activity of STS in our glial-mediated neuroinflammatory model. METHODS: Firstly, we measured glutathione (GSH) and hydrogen sulfide (H2S, SH(-)) levels in glial cells after treatment with sodium hydrosulfide (NaSH) or STS. We also measured released levels of tumor necrosis factor-α (TNFα) and interleukin-6 (IL-6) from them. We used two cell viability assays, MTT and lactate dehydrogenase (LDH) release assays, to investigate glial-mediated neurotoxicity and anti-inflammatory effects of NaSH or STS. We also employed Western blot to examine activation of intracellular inflammatory pathways. RESULTS: We found that STS increases H2S and GSH expression in human microglia and astrocytes. When human microglia and astrocytes are activated by lipopolysaccharide (LPS)/interferon-γ (IFNγ) or IFNγ, they release materials that are toxic to differentiated SH-SY5Y cells. When the glial cells were treated with NaSH or STS, there was a significant enhancement of neuroprotection. The effect was concentration-dependent and incubation time-dependent. Such treatment reduced the release of TNFα and IL-6 and also attenuated activation of P38 MAPK and NFκB proteins. The compounds tested were not harmful when applied directly to all the cell types. CONCLUSIONS: Although NaSH was somewhat more powerful than STS in these in vitro assays, STS has already been approved as an orally available treatment. STS may therefore be a candidate for treating neurodegenerative disorders that have a prominent neuroinflammatory component.


Asunto(s)
Antioxidantes/farmacología , Neuroglía/efectos de los fármacos , Tiosulfatos/farmacología , Proteínas de Unión al Calcio , Diferenciación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/ética , Células Cultivadas , Medios de Cultivo Condicionados/farmacología , Proteínas de Unión al ADN/metabolismo , Proteína Ácida Fibrilar de la Glía/metabolismo , Humanos , Hidroliasas/metabolismo , Sulfuro de Hidrógeno/metabolismo , Concentración 50 Inhibidora , Interferón gamma/farmacología , Interleucina-6/metabolismo , Lipopolisacáridos/farmacología , Proteínas de Microfilamentos , Factores de Tiempo , Tretinoina/farmacología , Factor de Necrosis Tumoral alfa/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
8.
Neuropharmacology ; 100: 124-30, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26025659

RESUMEN

Bexarotene has been reported to reduce brain amyloid-ß (Aß) levels and to improve cognitive function in transgenic mouse models of Alzheimer's disease (AD). Four groups failed to fully replicate the primary results but the original authors claimed overall support for the general conclusions. Because of its potential clinical importance, the current work studied the effects of bexarotene using two animal species and highly relevant paradigms. Rats were tested for the ability of bexarotene to prevent changes induced by an Aß challenge in the form intracerebroventricular (i.c.v) administration of 7PA2 conditioned medium (7PA2 CM) which contains high levels of Aß species. Bexarotene had no effect on the long-term potentiation of evoked extracellular field excitatory postsynaptic potentials induced by i.c.v. 7PA2 CM. It also had no effect following subcutaneous administration of 2, 5, 10 and 15 mg/kg on behavioral/cognitive impairment using an alternating-lever cyclic-ratio schedule of operant responding in the rat. The effects of bexarotene were further tested using the APPSwFILon, PSEN1*M146L*L286V transgenic mouse model of AD, starting at the time Aß deposits first begin to develop. Mice were sacrificed after 48 days of exposure to 100 mg bexarotene per day. No significant difference between test and control mice was found using a water-maze test, and no significant difference in the number of Aß deposits in cerebral cortex, using two different antibodies, was apparent. These results question the potential efficacy of bexarotene for AD treatment, even if instigated in the preclinical period prior to the onset of cognitive deficits reported for human AD. This article is part of the Special Issue entitled 'Synaptopathy--from Biology to Therapy'.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Región CA1 Hipocampal/efectos de los fármacos , Tetrahidronaftalenos/administración & dosificación , Enfermedad de Alzheimer/inducido químicamente , Enfermedad de Alzheimer/fisiopatología , Enfermedad de Alzheimer/prevención & control , Péptidos beta-Amiloides/toxicidad , Animales , Bexaroteno , Región CA1 Hipocampal/metabolismo , Región CA1 Hipocampal/fisiopatología , Células CHO , Condicionamiento Operante/efectos de los fármacos , Cricetulus , Medios de Cultivo Condicionados , Modelos Animales de Enfermedad , Potenciales Postsinápticos Excitadores/efectos de los fármacos , Potenciación a Largo Plazo/efectos de los fármacos , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Ratones , Ratones Transgénicos , Ratas , Ratas Sprague-Dawley
9.
CNS Neurol Disord Drug Targets ; 14(2): 251-6, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25687700

RESUMEN

Activated astrocytes, which can also be referred to as reactive astrocytes or astrogliosis, have been identified in affected regions of common neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis and multiple sclerosis. Activated astrocytes may be beneficial, promoting neuronal survival due to their production of growth factors and neurotrophins. Activated astrocytes can also be detrimental to neighboring neurons in neuroinflammatory processes. Astrocytes exposed to certain inflammatory stimulants in vitro have been shown to release potentially neurotoxic molecules, including inflammatory cytokines, glutamate, nitric oxide and reactive oxygen species. It has recently been shown that adult human astrocytes stimulated with interferon-γ, a common inflammatory cytokine evidently present in neuropathological brains, exert potent neurotoxicity in vitro. This interferon- γ-induced astrocytic neurotoxicity is mediated by the activation of the Janus kinase-signal transducer and activator of transcription (STAT) 3 pathway in the astrocytes, and involves intracellular phosphorylation of STAT3 at tyrosine-705 residue. Therefore, control of STAT3 activation in human astrocytes may be a promising new therapeutic strategy for a broad spectrum of neurodegenerative and neuroinflammatory disorders where activated astrocytes may contribute to the pathology.


Asunto(s)
Antivirales/efectos adversos , Astrocitos/efectos de los fármacos , Interferón gamma/efectos adversos , Síndromes de Neurotoxicidad/etiología , Síndromes de Neurotoxicidad/patología , Humanos
10.
Expert Opin Ther Targets ; 19(4): 497-506, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25435348

RESUMEN

INTRODUCTION: Activated microglia are associated with the progression of Alzheimer's disease (AD), as well as many other neurodegenerative diseases of aging. Microglia are therefore key targets for therapeutic intervention. AREAS COVERED: ß-amyloid (Aß) deposits activate the complement system, which, in turn, stimulates microglia to release neurotoxic materials. Research has focused primarily on anti-inflammatory agents to temper this toxic effect. More recently there has been a focus on converting microglia from this M1 state to an M2 state in which the toxic effects are reduced and their phagocytic activity toward Aß enhanced. Studies in transgenic mice have suggested a number of possible anti-inflammatory approaches but they may not always be a good model. An example is vaccination with antibodies to Aß, which is effective in mouse models, but has repeatedly failed in clinical trials. Biomarker studies indicate that AD commences many years prior to clinical onset. EXPERT OPINION: A hopeful approach to a disease-modifying treatment of AD is to administer agents that inhibit the inflammatory stimulation of microglia or successfully convert them to an M2 state. However, any such treatment must be started early in the disease.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Antiinflamatorios/uso terapéutico , Microglía/metabolismo , Enfermedad de Alzheimer/fisiopatología , Péptidos beta-Amiloides/metabolismo , Animales , Antiinflamatorios/farmacología , Biomarcadores/metabolismo , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Humanos , Ratones , Ratones Transgénicos
11.
PLoS One ; 9(1): e87316, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24489894

RESUMEN

OBJECTIVES: Paroxysmal nocturnal hemoglobinemia (PNH) is a rare but serious condition characterized by complement-mediated red blood cell (RBC) hemolysis and episodic thrombotic attack. It results from decay accelerating factor (CD55), and protectin (CD59), becoming attached to RBC and other cell surfaces. Absence of these protective proteins leaves such cells vulnerable to self attack at the C3 convertase and membrane attack complex (MAC) stages of complement activation. We have previously reported that aurin tricarboxylic acid (ATA) is an orally effective agent that selectively blocks complement activation at the C3 convertase stage as well as MAC formation at the C9 insertion stage. DESIGN AND METHODS: We used a CH50 assay method and western blot analysis to investigate the vulnerability to complement attack of PNH RBCs compared with normal RBCs. Zymosan was used as the activator of normal serum and PNH serum. ATA was added to the sera to determine the concentration necessary to protect the RBCs from lysis by the zymosan-activated sera. RESULTS: We found that erythrocytes from PNH patients on long term treatment with eculizumab were twice as vulnerable as normal erythrocytes to lysis induced by complement activated serum. Western blot data showed the presence of both C3 and C5 convertases on the PNH patient erythrocyte membranes. These data indicate persistent vulnerability of PNH erythrocytes to complement attack due to deficiencies in CD55 and CD59. ATA, when added to serum in vitro, protected PNH erythrocytes from complement attack, restoring their resistance to that of normal erythrocytes. CONCLUSIONS: We conclude that ATA, by protecting PNH erythrocytes from their decay accelerating factor (CD55) and protectin (CD59) deficiencies, may be an effective oral treatment in this disorder.


Asunto(s)
Ácido Aurintricarboxílico/farmacología , Fármacos Hematológicos/farmacología , Hemoglobinuria Paroxística/tratamiento farmacológico , Hemólisis/efectos de los fármacos , Adulto , Anticuerpos Monoclonales Humanizados/farmacología , Complemento C3b/metabolismo , Complemento C4b/metabolismo , Complemento C5/antagonistas & inhibidores , Complemento C5/metabolismo , Evaluación Preclínica de Medicamentos , Eritrocitos/efectos de los fármacos , Eritrocitos/fisiología , Femenino , Hemoglobinuria Paroxística/sangre , Humanos , Masculino , Adulto Joven
12.
Acta Neuropathol ; 126(4): 479-97, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24052108

RESUMEN

The amyloid cascade hypothesis is widely accepted as the centerpiece of Alzheimer disease (AD) pathogenesis. It proposes that abnormal production of beta amyloid protein (Abeta) is the cause of AD and that the neurotoxicity is due to Abeta itself or its oligomeric forms. We suggest that this, in itself, cannot be the cause of AD because demonstrating such toxicity requires micromolar concentrations of these Abeta forms, while their levels in brain are a million times lower in the picomolar range. AD probably results from the inflammatory response induced by extracellular Abeta deposits, which later become enhanced by aggregates of tau. The inflammatory response, which is driven by activated microglia, increases over time as the disease progresses. Disease-modifying therapeutic attempts to date have failed and may continue to do so as long as the central role of inflammation is not taken into account. Multiple epidemiological and animal model studies show that NSAIDs, the most widely used antiinflammatory agents, have a substantial sparing effect on AD. These studies provide a proof of concept regarding the anti-inflammatory approach to disease modification. Biomarker studies have indicated that early intervention may be necessary. They have established that disease onset occurs more than a decade before it becomes clinically evident. By combining biomarker and pathological data, it is possible to define six phases of disease development, each separated by about 5 years. Phase one can be identified by decreases in Abeta in the CSF, phase 2 by increases of tau in the CSF plus clear evidence of Abeta brain deposits by PET scanning, phase 3 by slight decreases in brain metabolic rate by PET-FDG scanning, phase 4 by slight decreases in brain volume by MRI scanning plus minimal cognitive impairment, phase 5 by increased scanning abnormalities plus clinical diagnosis of AD, and phase 6 by advanced AD requiring institutional care. Utilization of antiinflammatory agents early in the disease process remains an overlooked therapeutic opportunity. Such agents, while not preventative, have the advantage of being able to inhibit the consequences of both Abeta and tau aggregation. Since there is more than a decade between disease onset and cognitive decline, a window of opportunity exists to introduce truly effective disease-modifying regimens. Taking advantage of this opportunity is the challenge for the future.


Asunto(s)
Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/terapia , Amiloide/genética , Inflamación/genética , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Vacunas contra el Alzheimer/uso terapéutico , Péptidos beta-Amiloides/genética , Precursor de Proteína beta-Amiloide/genética , Animales , Animales Modificados Genéticamente , Antiinflamatorios/uso terapéutico , Antiinflamatorios no Esteroideos/uso terapéutico , Antioxidantes/uso terapéutico , Biomarcadores , Dieta , Humanos , Inmunización , Inflamación/metabolismo , Inflamación/patología , Mutación/genética , Fragmentos de Péptidos/genética , Investigación Biomédica Traslacional
13.
Neurobiol Aging ; 34(5): 1451-61, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23177218

RESUMEN

Aberrant complement activation is known to exacerbate the pathology in a spectrum of degenerative diseases of aging. We previously reported that aurin tricarboxylic acid (ATA) is an orally effective agent which prevents formation of the membrane attack complex of complement. It inhibits C9 attachment to tissue bound C5b678 and thus prevents bystander lysis of host cells. In this study, we investigated the effects of ATA on the alternative complement pathway. We found that ATA prevented cleavage of the tissue bound properdin-C3b-Factor B complex into the active C3 convertase enzyme properdin-C3b-Factor Bb. This inhibition was reversed by adding Factor D to the serum. Using enzyme-linked immunosorbent type assays, we established that ATA binds directly to Factor D and C9 but not to properdin or other complement proteins. We conclude that ATA, by inhibiting at two stages of the alternative pathway, might be a particularly effective therapeutic agent in conditions such as macular degeneration, paroxysmal nocturnal hemoglobinemia, and rheumatoid arthritis, in which activation of the alternative complement pathway initiates self damage.


Asunto(s)
Ácido Aurintricarboxílico/farmacología , Activación de Complemento/inmunología , Convertasas de Complemento C3-C5/inmunología , Complemento C9/inmunología , Complejo de Ataque a Membrana del Sistema Complemento/inmunología , Activación de Complemento/efectos de los fármacos , Complejo de Ataque a Membrana del Sistema Complemento/efectos de los fármacos , Humanos , Fármacos Neuroprotectores/farmacología , Unión Proteica
14.
J Alzheimers Dis ; 33(4): 1073-88, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23114513

RESUMEN

The GABAergic system is the main inhibitory neurotransmitter system in the vertebrate brain. Although it is well established that the GABAergic system is affected in neuropsychiatric disorders, in Alzheimer's disease (AD) it has been considered to be relatively spared. In this study we describe the immunohistochemical localization of the main enzymes of the GABAergic system; glutamate decarboxylase 65 (GAD65), GAD67, and GABA transferase (GABAT) in human brain. In neocortex, hippocampus, basal ganglia, and cerebellum, GAD65 and GAD67 immunoreactivity were found in neuropil granules, possibly axonal boutons or terminals, and in a subset of small to midsized neurons. GAD65 preferentially stained neuropil granules, while GAD67 preferentially stained neuronal cell bodies. GABAT intensely labeled many types of neurons and glia cells. While GAD65 and GAD67 stained the cytoplasm of cells homogeneously, GABAT labeling appeared irregular and granular. GAD65 immunoreactivity of neurons and neuropil was severely reduced in AD middle temporal gyrus, hippocampus, and putamen as determined by fluorescence and light microscopic immunohistochemistry. Western blotting revealed a similar reduction of GAD65, but not GAD67, protein levels in the middle temporal gyrus of AD. Our results suggest that the GABAergic system is more severely affected in AD than previously reported. This deficit may contribute to AD pathogenesis by loss of GABAergic inhibitory activity.


Asunto(s)
4-Aminobutirato Transaminasa/metabolismo , Enfermedad de Alzheimer/enzimología , Encéfalo/enzimología , Glutamato Descarboxilasa/metabolismo , 4-Aminobutirato Transaminasa/análisis , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/patología , Encéfalo/patología , Química Encefálica/fisiología , Estudios de Casos y Controles , Femenino , Glutamato Descarboxilasa/análisis , Humanos , Masculino , Persona de Mediana Edad
15.
Neurobiol Aging ; 33(10): 2237-46, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22217416

RESUMEN

Complement plays a vital role in both the innate and adaptive immune systems. It recognizes a target, opsonizes it, generates anaphylatoxins, and directly kills cells through the membrane attack complex (MAC). This final function, which assembles C5b-9(n) on viable cell surfaces, can kill host cells through bystander lysis. Here we identify for the first time compounds that can inhibit bystander lysis while not interfering with the other essential functions of complement. We show that aurin tricarboxylic acid (ATA), aurin quadracarboxylic acid (AQA), and aurin hexacarboxylic acid (AHA), block the addition of C9 to C5b-8 so that the MAC cannot form. These molecules inhibit hemolysis of human, rat, and mouse red cells with a half maximal inhibitory concentration (IC(50)) in the nanomolar range. When given orally to Alzheimer disease type B6SJL-Tg mice, they inhibit MAC formation in serum and improve memory retention. On autopsy, they show no evidence of harm to any organ. Aurin tricarboxylic acid, aurin quadracarboxylic acid, and aurin hexacarboxylic acid may be effective therapeutic agents in Alzheimer disease and other degenerative disorders where self damage from the MAC occurs.


Asunto(s)
Ácido Aurintricarboxílico/análogos & derivados , Ácido Aurintricarboxílico/farmacología , Proteínas del Sistema Complemento/efectos de los fármacos , Salicilatos/farmacología , Enfermedad de Alzheimer/tratamiento farmacológico , Animales , Ácido Aurintricarboxílico/síntesis química , Efecto Espectador/efectos de los fármacos , Proteínas del Sistema Complemento/química , Hemólisis/efectos de los fármacos , Humanos , Memoria/efectos de los fármacos , Ratones , Ratones Transgénicos , Ratas , Salicilatos/síntesis química
16.
Neurosci Lett ; 506(1): 149-54, 2012 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-22085693

RESUMEN

Optineurin mutations cause adult-onset primary open-angle glaucoma and have been associated with some familial forms of amyotrophic lateral sclerosis (ALS). Optineurin is involved in many cellular processes and interacts with a variety of proteins, among them huntingtin (htt). Here we report that in Huntington's disease (HD) cortex, optineurin frequently occurs in neuronal intranuclear inclusions, and to a lesser extent, in inclusions in the neuropil and in perikarya. Most intranuclear optineurin-positive inclusions were co-labeled for ubiquitin, but they were only occasionally and more weakly co-labeled for htt. Optineurin-labeled neuropil and perikaryal inclusions were commonly co-labeled for ubiquitin and htt. Although these inclusions were common in cortex, they were rare in striatum. Our results show that in HD optineurin is present in intranuclear, neuropil and perikaryal inclusions. It is not clear whether this indicates a primary involvement in the disease process. In HD, the known interaction of htt and optineurin may suggest that a different process takes place as compared to other neurodegenerative disorders.


Asunto(s)
Encéfalo/ultraestructura , Enfermedad de Huntington/patología , Cuerpos de Inclusión Intranucleares/metabolismo , Factor de Transcripción TFIIIA/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Encéfalo/patología , Proteínas de Ciclo Celular , Femenino , Humanos , Proteína Huntingtina , Masculino , Proteínas de Transporte de Membrana , Persona de Mediana Edad , Proteínas del Tejido Nervioso/metabolismo , Proteínas de Neurofilamentos/metabolismo , Proteínas Nucleares/metabolismo , Ubiquitina/metabolismo
17.
Front Pharmacol ; 2: 77, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22144960

RESUMEN

The foundations of innate immunity in neurodegenerative disorders were first laid by Del Rio Hortega (1919). He identified and named microglia, recognizing them as cells of mesodermal origin. Van Furth in 1969 elaborated the monocyte phagocytic system with microglia as the brain representatives. Validation of these concepts did not occur until 1987 when HLA-DR was identified on activated microglia in a spectrum of neurological disorders. HLA-DR had already been established as a definitive marker of immunocompetent cells of mesodermal origin. It was soon determined that the observed inflammatory reaction was an innate immune response. A rapid expansion of the field took place as other markers of an innate immune response were found that were made by neurons, astrocytes, oligodendroglia, and endothelial cells. The molecules included complement proteins and their regulators, inflammatory cytokines, chemokines, acute phase reactants, prostaglandins, proteases, protease inhibitors, coagulation factors, fibrinolytic factors, anaphylatoxins, integrins, free radical generators, and other unidentified neurotoxins. The Nimmerjahn movies demonstrated that resting microglia were constantly active, sampling the surround, and responding rapidly to brain damage. Ways of reducing the neurotoxic innate immune response and stimulating a healing response continue to be sought as a means for ameliorating the pathology in a spectrum of chronic degenerative disorders.

18.
Glia ; 59(11): 1600-11, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21748804

RESUMEN

We have previously demonstrated that human astrocytes are GABAergic cells. Throughout the adult human brain, they express the GABA synthesizing enzyme GAD 67, the GABA metabolizing enzyme GABA-T, and the GABA(A) and GABA(B) receptors. GABA modulates the actions of microglia, indicating an important role for astrocytes beyond that of influencing neurotransmitter function. Here we report on the mechanisms by which astrocytes release GABA. Astrocytes were found to express the mRNA and protein for multiple GABA transporters, and multiple receptors for glutamate, GABA, and glycine. In culture, untreated human astrocytes maintained an intracellular GABA level of 2.32 mM. They exported GABA into the culture medium so that an intracellular-extracellular gradient of 3.64 fold was reached. Inhibitors of the GABA transporters GAT1, GAT2, and GAT3, significantly reduced this export in a Ca(2+)-independent fashion. Intracellular GABA levels were enhanced by treatment with the GABA-T inhibitors gabaculine or vigabatrin. Treatment with glutamate increased GABA release in a concentration-dependent fashion. This was partially inhibited by blockers of N-methyl-D-aspartate and kainate receptors. Conversely, glycine and D-serine, co-agonists of NMDA receptors, enhanced the GABA release. GABA release was accompanied by an increase in intracellular Ca(2+) concentration ([Ca(2+)](i)) and was reduced by adding the Ca(2+) chelator, BAPTA-AM to the medium. These data indicate that astrocytes continuously synthesize GABA and that there are multiple mechanisms which can mediate its release. Each of these may play a role in the physiological functioning of astrocytes.


Asunto(s)
Astrocitos/metabolismo , Ácido gamma-Aminobutírico/metabolismo , Astrocitos/química , Western Blotting , Calcio/análisis , Calcio/metabolismo , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Quelantes/farmacología , Medios de Cultivo , Ácidos Ciclohexanocarboxílicos/farmacología , Cartilla de ADN , Ácido Egtácico/análogos & derivados , Ácido Egtácico/farmacología , Agonistas de Aminoácidos Excitadores/farmacología , Ácido Glutámico/farmacología , Humanos , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores de Glutamato/metabolismo , Proteínas de Transporte Vesicular de Glutamato/antagonistas & inhibidores , Proteínas de Transporte Vesicular de Glutamato/genética , Proteínas de Transporte Vesicular de Glutamato/metabolismo , Vigabatrin/farmacología
19.
J Alzheimers Dis ; 19(1): 355-61, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20061650

RESUMEN

Neuroinflammation is a prominent feature of Alzheimer disease (AD) and other chronic neurodegenerative disorders. It exacerbates the fundamental pathology by generating a plethora of inflammatory mediators and neurotoxic compounds. Inflammatory cytokines, complement components, and toxic free radicals are among the many species that are generated. Microglia attack the pathological entities and may inadvertently injure host neurons. Recent evidence indicates that microglia can be stimulated to assume an antiinflammatory state rather than a proinflammatory state which may have therapeutic potential. Proinflammatory cytokines include IL-1, IL-6 and TNF, while antiinflammatory cytokines include IL-4 and IL-10. Complement activation is a separate process which causes extensive neuronal damage in AD through assembly of the membrane attack complex. Aggregated amyloid-beta is a potent activator of human complement but not of mouse complement. This is an important difference between AD and transgenic mouse models of AD. Many so far unexplored molecules may contribute to neuroinflammation or act to inhibit it. Stable isotope labeling by amino acids in cell culture (SILAC) analysis identified 174 proteins that were upregulated by two-fold or more, and 189 that were downregulated by 2-fold or more following inflammatory stimulation of microglial-like THP-1 cells. Neurotoxicity may result from any combination of these and further exploration is clearly warranted. In addition, many small molecules may play a significant role. One example is hydrogen sulfide which appears to be an endogenous antiinflammatory agent.


Asunto(s)
Enfermedad de Alzheimer/patología , Trastornos del Conocimiento/patología , Neurología/métodos , Neurología/tendencias , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/psicología , Animales , Trastornos del Conocimiento/psicología , Humanos , Inflamación/patología , Inflamación/psicología
20.
Biochem Biophys Res Commun ; 387(1): 149-52, 2009 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-19576176

RESUMEN

Mutations in the alpha synuclein gene (SNCA) are the most potent cause of autosomal dominant Parkinson disease (PD) while mutations in the leucine-rich repeat kinase 2 (LRRK2) gene are the most common cause. We hypothesized that a direct interaction may exist between their protein products. Here we show that full-length Lrrk2 or fragments containing its kinase domain have a significant capacity to phosphorylate recombinant alpha synuclein (Asyn) at serine 129. Such phosphorylated Asyn is the major component of pathological deposits in PD. We further show that the G2019S mutation in Lrrk2, which is the most common genetic determinant of PD, has a significantly greater capacity than wild-type Lrrk2 to phosphorylate Asyn. This suggests that the G2019S mutant protein may cause PD by generating pathological levels of phosphorylated Asyn. Controlling Lrrk2 Asyn phosphokinase activity may be an approach to disease modifying therapy for PD and other synucleinopathies.


Asunto(s)
Enfermedad de Parkinson/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Serina/metabolismo , alfa-Sinucleína/metabolismo , Línea Celular , Humanos , Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina , Mutación , Enfermedad de Parkinson/genética , Fosforilación , Estructura Terciaria de Proteína , Serina/genética , alfa-Sinucleína/genética
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