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1.
BMC Neurol ; 23(1): 233, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37328820

RESUMO

BACKGROUND: Sporadic late onset nemaline myopathy is a rare, progressive muscle disease, presenting in adulthood, mainly affecting proximal limb and bulbar muscles. Muscle biopsies show characteristic nemaline rods. The putative mechanism is considered immune-related. Other manifestations aside from neuromuscular symptoms have not been described previously. CASE PRESENTATION: We present a case with atypical sporadic late onset nemaline myopathy (SLONM) of a non-HIV, non-MGUS subtype, where skin manifestations preceded neuromuscular symptoms, and a residual thymus with the histology of thymic follicular hyperplasia was detected during the diagnostic workup. Thorough dermatological investigations could not explain the skin presentations. Muscle biopsy revealed variation in fiber diameter, ragged-red and COX-negative fibers associated with discrete fibrosis. Electron microscopy detected atrophic muscle fibres with disorganization of the myofibrils, nemaline rods and abnormal mitochondria. Single-fiber EMG suggested signs of a neuromuscular transmission defect, EMG showed signs of myopathy. Analyses of antibodies associated with myasthenia gravis were negative. The patient showed improvement after intravenous immunoglobulin treatment regarding both the skin and the muscle symptoms. CONCLUSIONS: Our case highlights the heterogeneity of SLONM with its varied spectrum of presentation. A unique combination of dermatological symptoms and SLONM could be seen with skin lesions as primary presenting symptoms. An association can be considered between the different manifestations, presumably based on immune etiology, where immunosuppressive therapy has been beneficial.


Assuntos
Miastenia Gravis , Miopatias da Nemalina , Humanos , Miopatias da Nemalina/complicações , Miopatias da Nemalina/tratamento farmacológico , Miopatias da Nemalina/diagnóstico , Imunossupressores , Imunoglobulinas Intravenosas , Músculos/patologia , Miastenia Gravis/complicações , Músculo Esquelético/patologia
2.
Int J Mol Sci ; 22(18)2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34576165

RESUMO

Introduction: Previously, we demonstrated the degeneration of axon terminals in mice after repeated injections of blood sera from amyotrophic lateral sclerosis (ALS) patients with identified mutations. However, whether a similar treatment affects the cell body of motor neurons (MNs) remained unresolved. Methods: Sera from healthy individuals or ALS patients with a mutation in different ALS-related genes were intraperitoneally injected into ten-week-old male Balb/c mice (n = 3/serum) for two days. Afterward, the perikaryal calcium level was measured using electron microscopy. Furthermore, the optical disector method was used to evaluate the number of lumbar MNs. Results: The cytoplasmic calcium level of the lumbar MNs of the ALS-serum-treated mice, compared to untreated and healthy-serum-treated controls, was significantly elevated. While injections of the healthy serum did not reduce the number of MNs compared to the untreated control group, ALS sera induced a remarkable loss of MNs. Discussion: Similarly to the distant motor axon terminals, the injection of blood sera of ALS patients has a rapid degenerative effect on MNs. Analogously, the magnitude of the evoked changes was specific to the type of mutation; furthermore, the degeneration was most pronounced in the group treated with sera from ALS patients with a mutation in the chromosome 9 open reading frame 72 gene.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Cálcio/metabolismo , Neurônios Motores/metabolismo , Esclerose Lateral Amiotrófica/sangue , Animais , Modelos Animais de Doenças , Imunoglobulinas/genética , Imunoglobulinas/metabolismo , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mutação/genética
3.
Int J Mol Sci ; 21(15)2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32756522

RESUMO

Previously, we demonstrated increased calcium levels and synaptic vesicle densities in the motor axon terminals (MATs) of sporadic amyotrophic lateral sclerosis (ALS) patients. Such alterations could be conferred to mice with an intraperitoneal injection of sera from these patients or with purified immunoglobulin G. Later, we confirmed the presence of similar alterations in the superoxide dismutase 1 G93A transgenic mouse strain model of familial ALS. These consistent observations suggested that calcium plays a central role in the pathomechanism of ALS. This may be further reinforced by completing a similar analytical study of the MATs of ALS patients with identified mutations. However, due to the low yield of muscle biopsy samples containing MATs, and the low incidence of ALS patients with the identified mutations, these examinations are not technically feasible. Alternatively, a passive transfer of sera from ALS patients with known mutations was used, and the MATs of the inoculated mice were tested for alterations in their calcium homeostasis and synaptic activity. Patients with 11 different ALS-related mutations participated in the study. Intraperitoneal injection of sera from these patients on two consecutive days resulted in elevated intracellular calcium levels and increased vesicle densities in the MATs of mice, which is comparable to the effect of the passive transfer from sporadic patients. Our results support the idea that the pathomechanism underlying the identical manifestation of the disease with or without identified mutations is based on a common final pathway, in which increasing calcium levels play a central role.


Assuntos
Esclerose Lateral Amiotrófica/genética , Axônios/metabolismo , Neurônios Motores/metabolismo , Superóxido Dismutase/genética , Vesículas Sinápticas/genética , Esclerose Lateral Amiotrófica/sangue , Esclerose Lateral Amiotrófica/patologia , Animais , Axônios/patologia , Cálcio/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Camundongos Transgênicos/genética , Camundongos Transgênicos/metabolismo , Neurônios Motores/patologia , Mutação/genética , Terminações Pré-Sinápticas/metabolismo , Terminações Pré-Sinápticas/patologia , Medula Espinal/metabolismo , Medula Espinal/patologia , Vesículas Sinápticas/patologia
4.
Int J Mol Sci ; 20(10)2019 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-31130623

RESUMO

In an earlier study, signs of commencing degeneration of spinal motor neurons were induced in mice with short-term intraperitoneal injections of immunoglobulin G (IgG) taken from patients with amyotrophic lateral sclerosis (ALS). Since in that study, neither weakness nor loss of motor neurons was noted, to test whether the ALS IgG in this paradigm has the potential to evoke relentless degeneration of motor neurons, treatment with repeated injections over a longer period was carried out. Mice were systematically injected intraperitoneally with serum taken from ALS patients over a 75-day period. At selected time points, the isometric force of the limbs, number of spinal motor neurons and their intracellular calcium levels were determined. Furthermore, markers of glial activation and the motoneuronal uptake of human IgG were monitored. During this period, gliosis and progressive motoneuronal degeneration developed, which led to gradual loss of spinal motor neurons, more than 40% at day 21, along with decreasing muscle strength in the limbs. The inclusion-like accumulation of IgG appeared in the perikarya with the increase of intracellular calcium in the cell bodies and motor nerve terminals. Our results demonstrate that ALS serum can transfer motor neuron disease to mice.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Doença dos Neurônios Motores/metabolismo , Neurônios Motores/patologia , Soro/metabolismo , Esclerose Lateral Amiotrófica/sangue , Animais , Cálcio/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Imunoglobulina G/administração & dosagem , Imunoglobulina G/sangue , Imunoglobulina G/metabolismo , Injeções Intraperitoneais , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Doença dos Neurônios Motores/patologia , Neurônios Motores/metabolismo
5.
J Clin Neurosci ; 48: 7-10, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29133107

RESUMO

Neuromyelitis optica spectrum disorders (NMOSD) are demyelinating, autoimmune diseases affecting the central nervous system. Typically, recurrent optic neuritis and longitudinal extensive transverse myelitis dominates the clinical picture. In most cases NMOSD are associated with autoantibodies targeting the water channel aquaporin-4 (AQP-4). NMOSD usually present in young adults. Clinical findings suggestive of NMOSD in elderly patients should raise the suspicion of a paraneoplastic etiology. To our knowledge, we report the first case of a 66 year-old female patient with paraneoplastic NMOSD that is associated with squamous cell lung carcinoma. Anti-AQP-4 was present in both the serum and cerebrospinal fluid of the patient. However, immunhistological staining of the malignant tissue did not show presence of AQP-4 on the surface of tumour cells.


Assuntos
Neuromielite Óptica/terapia , Polineuropatia Paraneoplásica/terapia , Idoso , Aquaporina 4/imunologia , Autoanticorpos/análise , Autoanticorpos/sangue , Autoanticorpos/líquido cefalorraquidiano , Carcinoma de Células Escamosas/complicações , Feminino , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/complicações , Imageamento por Ressonância Magnética , Neuromielite Óptica/complicações , Neuromielite Óptica/diagnóstico por imagem , Polineuropatia Paraneoplásica/diagnóstico por imagem , Polineuropatia Paraneoplásica/etiologia , Fumar , Coluna Vertebral/diagnóstico por imagem
6.
Int Heart J ; 58(3): 454-458, 2017 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-28496025

RESUMO

Fabry disease (FD) is an X-linked inherited lysosomal storage disorder caused by mutations in the GLA gene, encoding for the enzyme α-galactosidase A. Although hundreds of mutations in the GLA gene have been described, many of them are variants of unknown significance. Here we report a novel GLA mutation, p.Ile239Met, identified in a large Hungarian three-generation family with FD. A 69 year-old female index patient with a clinical history of renal failure, hypertrophic cardiomyopathy, and 2nd degree AV block was screened for mutation in the GLA gene. Genetic screening identified a previously unreported heterozygous mutation in exon 5 of the GLA gene (c.717A>G; p.Ile239Met). Family screening indicated that altogether 6 family members carried the mutation (5 females, 1 male, average age: 55 ± 16 years). Three family members, including the index patient, manifested the cardiac phenotype of hypertrophic cardiomyopathy, while two other family members were diagnosed with left ventricular hypertrophy. Taking affection status as the presence of hypertrophic cardiomyopathy, left ventricular hypertrophy or elevated lyso-Gb3 levels, all affected family members carried the mutation. Linkage analysis of the family gave a two-point LOD score of 2.01 between the affection status and the p.Ile239Met GLA mutation. Lyso-Gb3 levels were elevated in all carrier family members (range: 2.4-13.8 ng/mL; upper limit of normal +2STD: ≤ 1.8 ng/mL). The GLA enzyme level was markedly reduced in the affected male family member (< 0.2 µmol/L/hour; upper limit of normal ± 2STD: ≥ 2.6 µmol/L/hour). We conclude that the p. Ile239Met GLA mutation is a pathogenic mutation for FD associated with predominant cardiac phenotype.


Assuntos
DNA/genética , Doença de Fabry/genética , Testes Genéticos/métodos , Hipertrofia Ventricular Esquerda/genética , Mutação , alfa-Galactosidase/genética , Adulto , Análise Mutacional de DNA , Doença de Fabry/complicações , Doença de Fabry/metabolismo , Feminino , Humanos , Hipertrofia Ventricular Esquerda/etiologia , Hipertrofia Ventricular Esquerda/metabolismo , Linhagem , Fenótipo , alfa-Galactosidase/metabolismo
7.
Biochim Biophys Acta Mol Basis Dis ; 1863(7): 1739-1748, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28528135

RESUMO

Increased intracellular calcium (Ca), which might be the consequence of an excess influx through Ca-permeable α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, plays a crucial role in degeneration of motor neurons. Previously we demonstrated that the presymptomatic application of AMPA receptor antagonist, talampanel, could reduce Ca elevation in spinal motor neurons of mice carrying the G93A mutation of superoxide dismutase 1 (SOD1), modeling amyotrophic lateral sclerosis (ALS). It remained to be examined whether the remote, functionally semi-autonomous motor axon terminals could be rescued from the Ca overload, or if the terminals, where the degeneration possibly starts, already experience intractable changes at early time points. Thus using electron microscopic techniques, we measured the Ca level of motor axon terminals in the interosseus muscle of the SOD1 mutant animals, which are prototypes of vulnerable nerve endings in ALS. In line with the results obtained in the perikarya, talampanel treatment could reduce Ca increase evoked by the presence of mutant SOD1 in the axon terminals if the treatment was started presymptomatically but not at an early symptomatic stage. We also tested the Ca level in the cell bodies and axon terminals of the oculomotor neurons, which are resistant to the disease. Neither Ca increase, nor talampanel effect could be demonstrated at either time point. This is consistent with the observations that oculomotor neurons contain increased level of Ca buffer, which could reduce excess Ca load, and they also express glutamate receptor subunit type 2, which renders AMPA receptors impermeable to Ca.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Benzodiazepinas/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Cálcio/metabolismo , Terminações Pré-Sinápticas/metabolismo , Receptores de AMPA/antagonistas & inibidores , Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/patologia , Animais , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Transgênicos , Terminações Pré-Sinápticas/patologia , Receptores de AMPA/genética , Receptores de AMPA/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
8.
Ideggyogy Sz ; 70(7-8): 247-257, 2017 Jul 30.
Artigo em Húngaro | MEDLINE | ID: mdl-29870639

RESUMO

Amyotrophic lateral sclerosis (ALS), the most frequent motor neuron disease is characterized by progressive muscle weakness caused by the degeneration of the motor neurons in the spinal cord and motor cortex. However, according to the recent observations, ALS is a rather complex syndrome which frequently involves symptoms of cognitive impairment. Therefore, ALS cases can be interpreted in a clinico-pathological spectrum spanning from the classical ALS involving only the motor system to the fronto-temporal dementia. The progression of the disease, however, manifested in the degeneration of the upper and lower motor neurons, is based on the same complex pathobiology. The main elements of the pathomechanism, such as oxidative stress, excitotoxicity, immune/inflammatory processes and mitochondrial dysfunction are well described already, which operate in orchestrated way and amplify the deleterious effect of each other. It is assumed that calcium ions act as a catalyst in this interaction, hence each of the individual mechanisms has strong, positive and reciprocal calcium dependence thus may combine the individual pathological processes into a unified escalating mechanism of neuronal destruction. This review provides an overview of the role of calcium in connecting and amplifying the major mechanisms which lead to degeneration of the motor neurons in ALS.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Cálcio/metabolismo , Humanos , Íons/metabolismo , Neurônios Motores/metabolismo , Degeneração Neural/metabolismo
9.
CNS Neurol Disord Drug Targets ; 16(3): 356-367, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28017131

RESUMO

BACKGROUND: Motoneurons with naturally elevated calcium binding protein content, such as parvalbumin, are more resistant against injury. Furthermore, increase of intracellular calcium, which plays a pivotal role in injury of neurons, could be moderated by elevating their calcium binding proteins. OBJECTIVE: To test whether by elevating parvalbumin content of motoneurons, activation of neighboring microglial cells, a robust component of the inflammatory reaction after injury, could be influenced. METHODS: Mice overexpressing neuronal parvalbumin were derived and the spinal motoneurons were challenged by cutting the sciatic nerve. At postoperative days 1, 4, 7, 14 and 21 the change of the chemokine ligand 2 immunostaining in the motoneurons and the activation of microglial cells, measured as alterations in CD11b immunostaining were determined. Calcium level of motoneurons was tested electron microscopically at postoperative day 7. RESULTS: After axotomy, increased level of chemokine ligand 2 was detected in the lumbar motoneurons. The staining intensity reached its maximum at day 7 and decayed faster in transgenic mice compared to controls. Microglial activation around motoneurons attenuated faster in parvalbumin overexpressing mice, too, but the decrease of microglial activation was delayed compared to the decline of the chemokine ligand 2 signal. At the time when the microglial reaction peaked, no intracellular calcium increase was detected in the motoneurons of transgenic mice, in contrast to the twofold increase in wild type animals. CONCLUSION: Increased calcium buffering capacity, which augments resistance of motoneurons against calcium-mediated injury, leads to earlier termination of motoneuronal emission of CCL2 followed by a reduction of neighboring microglial activation after axotomy.


Assuntos
Cálcio/metabolismo , Quimiocina CCL2/metabolismo , Regulação da Expressão Gênica/fisiologia , Microglia/metabolismo , Neurônios Motores/metabolismo , Parvalbuminas/metabolismo , Neuropatia Ciática/patologia , Análise de Variância , Anestésicos/farmacologia , Animais , Antígenos CD/metabolismo , Axotomia/efeitos adversos , Modelos Animais de Doenças , Etanol/análogos & derivados , Etanol/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Microscopia Eletrônica , Neurônios Motores/ultraestrutura , Parvalbuminas/genética , Parvalbuminas/ultraestrutura , Neuropatia Ciática/metabolismo , Fatores de Tempo
10.
CNS Neurol Disord Drug Targets ; 16(3): 234-243, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27719624

RESUMO

Parkinson's disease (PD) is a progressive neurodegenerative disorder with prominent motor and non-motor symptoms. Psychosis develops in over 40% of PD patients and it is one of the most distressing symptoms for patients and caregivers alike. Until recently, atypical antipsychotics, clozapine and quetiapine were used to treat psychotic symptoms, but treatment was associated with substantial concerns for side-effects of clozapine and unfounded efficacy for quetiapine. Extensive research has shown that the antipsychotic effect of these drugs could be attributed to serotonin 2a receptor (5-HT2A) triggered mechanisms. A selective 5-HT2A inverse agonist, pimavanserin, has been developed, investigated and has gained approval in April 2016 in the US for the treatment of hallucinations and delusions in PD. In this review we primarily focus on psychosis in PD, the current treatment possibilities and the new, emerging therapy, pimavanserin, a selective 5-HT2A inverse agonist. All articles were reviewed in this topic and indexed in PubMed with keywords: Parkinson's disease psychosis, serotonin 2a receptor inverse agonist, clozapine, quetiapine, pimavanserin.


Assuntos
Doença de Parkinson/complicações , Piperidinas/uso terapêutico , Transtornos Psicóticos/tratamento farmacológico , Transtornos Psicóticos/etiologia , Agonistas do Receptor 5-HT2 de Serotonina/uso terapêutico , Ureia/análogos & derivados , Animais , Humanos , Doença de Parkinson/tratamento farmacológico , Receptor 5-HT2A de Serotonina/metabolismo , Ureia/uso terapêutico
11.
J Neuroinflammation ; 13(1): 121, 2016 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-27220674

RESUMO

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that involves the selective loss of the upper and lower motor neurons (MNs). Neuroinflammation has been implicated in the pathogenesis of the sporadic form of the disease. We earlier developed immune-mediated animal models of ALS and demonstrated humoral and cellular immune reactions in the nervous system and in the sera of patients and animals. The accumulation of immunoglobulin G (IgG), an elevated intracellular level of calcium, ultrastructural alterations in the MNs, and activation of the microglia were noted in the spinal cord of ALS patients. Similar alterations developed in mice inoculated intraperitoneally with IgG from ALS patients or from an immune-mediated goat model. METHODS: We have now examined whether the intraperitoneal injection of mice with IgG from sporadic ALS patients or from immunized goats with the homogenate of the anterior horn of the bovine spinal cord is associated with changes in the pro-inflammatory (TNF-α and IL-6) and anti-inflammatory (IL-10) cytokines in the spinal cord and serum of the mice. The levels of cytokines were measured by ELISA. RESULTS: Intraperitoneally administered IgG from the ALS patients induced subclinical signs of MN disease, while the injection of IgG from immunized goats resulted in a severe respiratory dysfunction and limb paralysis 24 h after the injections. Significantly increased levels of TNF-α and IL-10 were detected in the spinal cord of the mice injected with the human ALS IgG. The level of IL-6 increased primarily in the serum. The IgG from the immunized goats induced highly significant increases in the levels of all three cytokines in the serum and the spinal cord of mice. CONCLUSIONS: Our earlier experiments had proved that when ALS IgG or IgG from immune-mediated animal models was inoculated into mice, it was taken up in the MNs and had the ability to initiate damage in them. The pathological process was paralleled by microglia recruitment and activation in the spinal cord. The present experiment revealed that these forms of IgG cause significant increases in certain cytokine levels locally in the spinal cord and in the serum of the inoculated mice. These results suggest that IgG directed to the MNs may be an initial element in the damage to the MNs both in human ALS and in its immune-mediated animal models.


Assuntos
Esclerose Lateral Amiotrófica/sangue , Citocinas/metabolismo , Imunoglobulina G/administração & dosagem , Medula Espinal/metabolismo , Esclerose Lateral Amiotrófica/imunologia , Análise de Variância , Animais , Cálcio/metabolismo , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Cabras , Humanos , Injeções Intraperitoneais , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , Atividade Motora/efeitos dos fármacos , Neurônios Motores/patologia , Neurônios Motores/ultraestrutura , Miastenia Gravis Autoimune Experimental/sangue , Miastenia Gravis Autoimune Experimental/imunologia , Miastenia Gravis Autoimune Experimental/patologia , Fator de Necrose Tumoral alfa/metabolismo
13.
J Parkinsons Dis ; 4(2): 139-50, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24346238

RESUMO

The pathomechanism behind the neurodegenerative process in Parkinson's disease involves damage to the dopaminergic and nondopaminergic systems with dysfunctioning of the dopaminergic-glutamatergic circuitry in the basal ganglional neural processing. Excitotoxicity may contribute markedly to neuronal damage and loss. Beside the cardinal motor signs of the disease, non-motor symptoms, including mental disturbances, are characteristic features of the clinical course. Affective or autonomic changes may precede motor symptoms. Neuroprotective drugs are not yet available. However, new modes of therapy targeting the defective dopaminergic-glutamatergic system might also be effective both for symptomatologic treatment and for neuroprotection. Alterations in the kynurenine pathway have been demonstrated in Parkinson's disease. Preclinical studies suggest that intervention in the kynurenine pathway may result in neuroprotection and additionally alleviate the symptoms through influencing the glutamatergic neurotransmission.


Assuntos
Transtornos Mentais/etiologia , Transtornos Mentais/metabolismo , Neurotoxinas/metabolismo , Doença de Parkinson/complicações , Doença de Parkinson/metabolismo , Dopamina/metabolismo , Ácido Glutâmico/metabolismo , Humanos , Cinurenina/metabolismo , Transtornos Mentais/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico
14.
Eur J Microbiol Immunol (Bp) ; 3(4): 281-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24294499

RESUMO

Serum amyloid P component (SAP), a member of the innate immune system, does not penetrate the brain in physiological conditions; however, SAP is a stabilizing component of the amyloid plaques in neurodegenerative diseases. We investigated the cerebrovascular transport of human SAP in animal experiments and in culture blood-brain barrier (BBB) models. After intravenous injection, no SAP could be detected by immunohistochemistry or ELISA in healthy rat brains. Salmonella typhimurium lipopolysaccharide injection increased BBB permeability for SAP and the number of cerebral vessels labeled with fluorescein isothiocyanate (FITC)-SAP in mice. Furthermore, when SAP was injected to the rat hippocampus, a time-dependent decrease in brain concentration was seen demonstrating a rapid SAP efflux transport in vivo. A temperature-dependent bidirectional transport of FITC-SAP was observed in rat brain endothelial monolayers. The permeability coefficient for FITC-SAP was significantly higher in abluminal to luminal (brain to blood) than in the opposite direction. The luminal release of FITC-SAP from loaded endothelial cells was also significantly higher than the abluminal one. Our data indicate the presence of BBB efflux transport mechanisms protecting the brain from SAP penetration. Damaged BBB integrity due to pathological insults may increase brain SAP concentration contributing to development of neurodegenerative diseases.

15.
J Comp Neurol ; 499(1): 17-32, 2006 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-16958104

RESUMO

Motor neurons with different susceptibility to degeneration have been identified in amyotrophic lateral sclerosis (ALS). Increase of intracellular calcium has been proposed as a mediator, amplifying the damage through a positive feedback of the known pathological processes. Accordingly, the potential of motor neurons to limit calcium increases during injury might be proportional to their viability. A basic mechanism of reducing calcium amplitudes depends on the calcium-buffering capacity, determined by the calcium-binding protein content. In this study, oculomotor and hypoglossal neurons, prototypes of resistant and vulnerable motor neurons in ALS were examined in axotomy experiments. Total calcium-, parvalbumin-, and calbindin-D28k levels of motor neurons of adult mice were characterized by electron microscopic histochemistry and light microscopic immunostaining. In hypoglossal neurons, compared with oculomotor neurons, larger and more enduring increases of calcium were detected. The perikarya of hypoglossal neurons remained immunonegative for both parvalbumin and calbindin-D28k. Qualitatively, no major cell loss was noted after axotomy, but a decreased neuronal marker staining at days 1-14 suggested a reversible injury of hypoglossal neurons. Oculomotor neurons were not stained for calbindin-D28k but stained for parvalbumin in control conditions, staining which increased at postoperative days 7-14 before returning to baseline. Neuronal marker staining did not change in these cells during the observed period. The higher level of parvalbumin in resistant motor neurons and their ability to up-regulate parvalbumin after injury, paralleled by a smaller increase of intracellular calcium suggest that parvalbumin may have a protective effect in these cells.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Cálcio/metabolismo , Lateralidade Funcional/fisiologia , Nervo Hipoglosso/fisiologia , Neurônios Motores/metabolismo , Nervo Oculomotor/fisiologia , Animais , Axotomia/métodos , Calbindina 1 , Calbindinas , Regulação da Expressão Gênica/fisiologia , Imuno-Histoquímica/métodos , Masculino , Bulbo/citologia , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Imunoeletrônica/métodos , Neurônios Motores/ultraestrutura , Parvalbuminas/metabolismo , Fosfopiruvato Hidratase/metabolismo , Proteína G de Ligação ao Cálcio S100/metabolismo , Coloração e Rotulagem/métodos , Fatores de Tempo
16.
Neurosci Lett ; 352(1): 57-60, 2003 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-14615049

RESUMO

Endotoxin challenge leads to septic shock, multi-organ failure and death in mice. Permeability of the blood-brain barrier (BBB) is increased by endotoxemia. Serum amyloid P component (SAP) is a lipopolysaccharide (LPS)-binding protein that can modulate the host reactions during infections. It is controversial whether SAP can protect from LPS toxicity in vivo or not. We have tested the effect of human SAP on BBB permeability of Salmonella typhimurium LPS-injected mice. The animals showed signs of sickness behaviour including immobility, anorexia, and diarrhoea. Intraperitoneally administered LPS increased the BBB permeability for sodium fluorescein for about 4-fold, and for albumin for more than 2-fold in brain cortex. SAP, given intravenously, had no effect on basal BBB permeability for albumin, although it decreased sodium fluorescein extravasation to brain tissue. In LPS-treated mice, SAP administration alleviated the symptoms of septic shock, and significantly inhibited the enhanced BBB permeability for both tracers. Our data indicate that human SAP may counteract the toxic effects of LPS during septic shock.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Permeabilidade Capilar/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Componente Amiloide P Sérico/farmacologia , Animais , Barreira Hematoencefálica/metabolismo , Permeabilidade Capilar/fisiologia , Humanos , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacocinética , Masculino , Camundongos , Camundongos Endogâmicos CBA , Componente Amiloide P Sérico/farmacocinética
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