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1.
Cell Transplant ; 26(4): 647-658, 2017 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-27938483

RESUMO

Amyotrophic lateral sclerosis (ALS) is a progressive untreatable neurodegenerative disorder, leading to the death of the cortical and spinal motoneurons (MNs). Bone marrow-derived mesenchymal stem/stromal cells (BM-MSCs) may represent a new approach to slowing down the progression of ALS by providing neurotrophic support to host MNs and by having an anti-inflammatory effect. We have designed a prospective, nonrandomized, open-label clinical trial (phase I/IIa, EudraCT No. 2011-000362-35) to assess the safety and efficacy of autologous multipotent BM-MSCs in ALS treatment. Autologous BM-MSCs were isolated and expanded under GMP conditions. Patients received 15 ± 4.5 × 106 of BM-MSCs via lumbar puncture into the cerebrospinal fluid. Patients were monitored for 6 months before treatment and then for an 18-month follow-up period. Potential adverse reactions were assessed, and the clinical outcome was evaluated by the ALS functional rating scale (ALSFRS), forced vital capacity (FVC), and weakness scales (WSs) to assess muscle strength on the lower and upper extremities. In total, 26 patients were enrolled in the study and were assessed for safety; 23 patients were suitable for efficacy evaluation. After intrathecal BM-MSC application, about 30% of the patients experienced a mild to moderate headache, resembling the headaches after a standard lumbar puncture. No suspected serious adverse reactions (SUSAR) were observed. We found a reduction in ALSFRS decline at 3 months after application (p < 0.02) that, in some cases, persisted for 6 months ( p < 0.05). In about 80% of the patients, FVC values remained stable or above 70% for a time period of 9 months. Values of WS were stable in 75% of patients at 3 months after application. Our results demonstrate that the intrathecal application of BM-MSCs in ALS patients is a safe procedure and that it can slow down progression of the disease.


Assuntos
Esclerose Lateral Amiotrófica/terapia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Adulto , Esclerose Lateral Amiotrófica/fisiopatologia , Feminino , Seguimentos , Humanos , Masculino , Transplante de Células-Tronco Mesenquimais/efeitos adversos , Pessoa de Meia-Idade , Análise de Regressão , Resultado do Tratamento , Capacidade Vital
2.
Acta Vet Scand ; 56: 72, 2014 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-25391249

RESUMO

BACKGROUND: Hypoxia results in an imbalance between oxygen supply and oxygen consumption. This study utilized microdialysis to monitor changes in the energy-related metabolites lactate, pyruvate and glucose in rat muscle before, during and after 30 minutes of transient global hypoxia. Hypoxia was induced in anaesthetised rats by reducing inspired oxygen to 6% O2 in nitrogen. RESULTS: Basal values for lactate, the lactate/pyruvate ratio and glucose were 0.72 ± 0.04 mmol/l, 10.03 ± 1.16 and 3.55 ± 0.19 mmol/l (n = 10), respectively. Significant increases in lactate and the lactate/pyruvate ratio were found in the muscle after the induction of hypoxia. Maximum values of 2.26 ± 0.37 mmol/l for lactate were reached during early reperfusion, while the lactate/pyruvate ratio reached maximum values of 35.84 ± 7.81 at the end of hypoxia. Following recovery to ventilation with air, extracellular lactate levels and the lactate/pyruvate ratio returned to control levels within 30-40 minutes. Extracellular glucose levels showed no significant difference between hypoxia and control experiments. CONCLUSIONS: In our study, the complete post-hypoxic recovery of metabolite levels suggests that metabolic enzymes of the skeletal muscle and their related cellular components may be able to tolerate severe hypoxic periods without prolonged damage. The consumption of glucose in the muscle in relation to its delivery seems to be unaffected.


Assuntos
Glucose/metabolismo , Hipóxia/metabolismo , Ácido Láctico/metabolismo , Músculo Esquelético/metabolismo , Ácido Pirúvico/metabolismo , Animais , Metabolismo Energético , Hipóxia/etiologia , Masculino , Microdiálise , Ratos , Ratos Wistar
3.
Stem Cells ; 32(12): 3163-72, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25113670

RESUMO

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder resulting in a lethal outcome. We studied changes in ventral horn perineuronal nets (PNNs) of superoxide dismutase 1 (SOD1) rats during the normal disease course and after the intrathecal application (5 × 10(5) cells) of human bone marrow mesenchymal stromal cells (MSCs) postsymptom manifestation. We found that MSCs ameliorated disease progression, significantly improved motor activity, and prolonged survival. For the first time, we report that SOD1 rats have an abnormal disorganized PNN structure around the spinal motoneurons and give different expression profiles of chondroitin sulfate proteoglycans (CSPGs), such as versican, aggrecan, and phosphacan, but not link protein-1. Additionally, SOD1 rats had different profiles for CSPG gene expression (Versican, Hapln1, Neurocan, and Tenascin-R), whereas Aggrecan and Brevican profiles remained unchanged. The application of MSCs preserved PNN structure, accompanied by better survival of motorneurons. We measured the concentration of cytokines (IL-1α, MCP-1, TNF-α, GM-CSF, IL-4, and IFN-γ) in the rats' cerebrospinal fluid and found significantly higher concentrations of IL-1α and MCP-1. Our results show that PNN and cytokine homeostasis are altered in the SOD1 rat model of ALS. These changes could potentially serve as biological markers for the diagnosis, assessment of treatment efficacy, and prognosis of ALS. We also show that the administration of human MSCs is a safe procedure that delays the loss of motor function and increases the overall survival of symptomatic ALS animals, by remodeling the recipients' pattern of gene expression and having neuroprotective and immunomodulatory effects.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Células-Tronco Mesenquimais/citologia , Neurônios/citologia , Medula Espinal/metabolismo , Animais , Diferenciação Celular/fisiologia , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Matriz Extracelular/metabolismo , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Masculino , Rede Nervosa/citologia , Ratos , Fator de Necrose Tumoral alfa/metabolismo
4.
Eur J Neurosci ; 36(1): 2017-24, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22536791

RESUMO

Focal cortical dysplasias (FCDs) of the brain are recognized as a frequent cause of intractable epilepsy. To contribute to the current understanding of the mechanisms of epileptogenesis in FCD, our study provides evidence that not only cellular alterations and synaptic transmission, but also changed diffusion properties of the extracellular space (ECS), induced by modified extracellular matrix (ECM) composition and astrogliosis, might be involved in the generation or spread of seizures in FCD. The composition of the ECM in FCD and non-malformed cortex (in 163 samples from 62 patients) was analyzed immunohistochemically and correlated with the corresponding ECS diffusion parameter values determined with the real-time iontophoretic method in freshly resected cortex (i.e. the ECS volume fraction and the geometrical factor tortuosity, describing the hindrances to diffusion in the ECS). The ECS in FCD was shown to differ from that in non-malformed cortex, mainly by the increased accumulation of certain ECM molecules (tenascin R, tenascin C, and versican) or by their reduced expression (brevican), and by the presence of an increased number of astrocytic processes. The consequent increase of ECS diffusion barriers observed in both FCD type I and II (and, at the same time, the enlargement of the ECS volume in FCD type II) may alter the diffusion of neuroactive substances through the ECS, which mediates one of the important modes of intercellular communication in the brain - extrasynaptic volume transmission. Thus, the changed ECM composition and altered ECS diffusion properties might represent additional factors contributing to epileptogenicity in FCD.


Assuntos
Encefalopatias/patologia , Matriz Extracelular/química , Espaço Extracelular/química , Malformações do Desenvolvimento Cortical/patologia , Adolescente , Adulto , Astrócitos/metabolismo , Encefalopatias/metabolismo , Brevicam/análise , Criança , Pré-Escolar , Difusão , Epilepsia , Matriz Extracelular/metabolismo , Espaço Extracelular/metabolismo , Feminino , Humanos , Iontoforese/métodos , Masculino , Malformações do Desenvolvimento Cortical/metabolismo , Malformações do Desenvolvimento Cortical do Grupo I , Pessoa de Meia-Idade , Neocórtex/patologia , Tenascina/análise , Versicanas/análise , Adulto Jovem
5.
J Cereb Blood Flow Metab ; 28(10): 1665-73, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18545260

RESUMO

Changes in the extracellular space diffusion parameters during ischemia are well known, but information about changes during the postischemic period is lacking. Extracellular volume fraction (alpha) and tortuosity (lambda) were determined in the rat somatosensory cortex using the real-time iontophoretic method; diffusion-weighted magnetic resonance imaging was used to determine the apparent diffusion coefficient of water. Transient ischemia was induced by bilateral common carotid artery clamping for 10 or 15 mins and concomitant ventilation with 6% O(2) in N(2). In both ischemia groups, a negative DC shift accompanied by increased potassium levels occurred after 1 to 2 mins of ischemia and recovered to preischemic values within 3 to 5 mins of reperfusion. During ischemia of 10 mins duration, alpha typically decreased to 0.07+/-0.01, whereas lambda increased to 1.80+/-0.02. In this group, normal values of alpha=0.20+/-0.01 and lambda=1.55+/-0.01 were registered within 5 to 10 mins of reperfusion. After 15 mins of ischemia, alpha increased within 40 to 50 mins of reperfusion to 0.29+/-0.03 and remained at this level. Tortuosity (lambda) increased to 1.81+/-0.02 during ischemia, recovered within 5 to 10 mins of reperfusion, and was increased to 1.62+/-0.01 at the end of the experiment. The observed changes can affect the diffusion of ions, neurotransmitters, metabolic substances, and drugs in the nervous system.


Assuntos
Edema Encefálico/metabolismo , Espaço Extracelular/metabolismo , Hipóxia Encefálica/metabolismo , Ataque Isquêmico Transitório/metabolismo , Córtex Somatossensorial/metabolismo , Animais , Edema Encefálico/fisiopatologia , Circulação Cerebrovascular/fisiologia , Difusão , Imagem de Difusão por Ressonância Magnética , Hipóxia Encefálica/fisiopatologia , Ataque Isquêmico Transitório/fisiopatologia , Masculino , Potássio/metabolismo , Ratos , Ratos Wistar , Recuperação de Função Fisiológica/fisiologia , Córtex Somatossensorial/irrigação sanguínea , Água/metabolismo
6.
Exp Neurol ; 209(1): 145-54, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17961555

RESUMO

The real-time iontophoretic method using tetramethylammonium-selective microelectrodes and diffusion-weighted magnetic resonance imaging were used to measure the extracellular space volume fraction alpha, tortuosity lambda and apparent diffusion coefficient of water (ADC(W)) 240 min after the administration of pilocarpine in urethane-anaesthetized rats. The obtained data were correlated with extracellular lactate, glucose, and glutamate concentrations and the lactate/pyruvate-ratio, determined by intracerebral microdialysis. The control values of alpha and lambda were 0.19+/-0.004 and 1.58+/-0.01, respectively. Following pilocarpine application, alpha decreased to 0.134+/-0.012 100 min later. Thereafter alpha increased, reaching 0.176+/-0.009 140 min later. No significant changes in lambda were observed during the entire time course of the experiment. ADC(W) was significantly decreased 100 min after pilocarpine application (549+/-8 microm(2) s(-1)) compared to controls (603+/-11 microm(2) s(-1)); by the end of the experiments, ADC(W) had returned to control values. The basal cortical levels of lactate, the lactate/pyruvate ratio, glucose and glutamate were 0.61+/-0.05 mmol/l, 33.16+/-4.26, 2.42+/-0.13 mmol/l and 6.55+/-1.31 micromol/l. Pilocarpine application led to a rise in lactate, the lactate/pyruvate ratio and glutamate levels, reaching 2.92+/-0.60 mmol/l, 84.80+/-11.72 and 22.39+/-5.85 micromol/l within about 100 min, with a subsequent decrease to control values 140 min later. The time course of changes in glucose levels was different, with maximal levels of 3.49+/-0.24 mmol/l reached 40 min after pilocarpine injection and a subsequent decrease to 1.25+/-0.40 mmol/l observed 200 min later. Pathologically increased neuronal activity induced by pilocarpine causes cell swelling followed by a reduction in the ECS volume fraction, which can contribute to the accumulation of toxic metabolites and lead to the start of epileptic discharges.


Assuntos
Química Encefálica/fisiologia , Córtex Cerebral/metabolismo , Córtex Cerebral/fisiopatologia , Agonistas Muscarínicos , Pilocarpina , Estado Epiléptico/metabolismo , Estado Epiléptico/fisiopatologia , Animais , Água Corporal/metabolismo , Química Encefálica/efeitos dos fármacos , Imagem de Difusão por Ressonância Magnética , Eletrochoque , Metabolismo Energético/efeitos dos fármacos , Metabolismo Energético/fisiologia , Espaço Extracelular/efeitos dos fármacos , Espaço Extracelular/metabolismo , Glucose/metabolismo , Ácido Láctico/metabolismo , Masculino , Potenciais da Membrana/fisiologia , Microdiálise , Potássio/metabolismo , Ratos , Ratos Wistar , Sódio/metabolismo , Estado Epiléptico/induzido quimicamente
7.
Exp Neurol ; 203(1): 34-41, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16956608

RESUMO

Hypoxia results in both reversible and irreversible changes in the brain extracellular space (ECS). This study utilized microdialysis to monitor changes in the energy-related metabolites lactate, pyruvate, glucose and glutamate in the rat cortex before, during and after 30-min transient global hypoxia, induced in anesthetized rats by reducing inspired oxygen to 6% O(2) in nitrogen. Changes in metabolite levels were compared with ECS diffusion parameters calculated from diffusion curves of tetramethylammonium applied by iontophoresis. Significant increases in lactate concentration and the lactate/pyruvate ratio, as well as decreased glucose levels, were found in the cortex immediately after the induction of hypoxia. Following recovery to ventilation with air, extracellular lactate and glucose levels and the lactate/pyruvate ratio returned to control levels within 40, 20 and 30 min, respectively. Glutamate levels started to increase 20-30 min after the onset of hypoxia and returned to prehypoxic values within 30-40 min of reoxygenation. The ECS volume fraction alpha decreased by about 5% from 0.18+/-0.01 during the first 20-25 min of hypoxia; after 25 min alpha dropped a further 22% to 0.14+/-0.01. Within 10 min of reoxygenation, alpha returned to control values, then increased to 0.20+/-0.01 and remained at this level until the end of the experiment. The observed 22% decrease in alpha markedly influences dialysate levels measured during hypoxia. In our study, the complete posthypoxic recovery of cortical metabolite levels and ECS diffusion properties suggests that metabolic enzymes and related cellular components (e.g., mitochondria) may tolerate prolonged hypoxic periods and recover to prehypoxic values.


Assuntos
Córtex Cerebral/metabolismo , Córtex Cerebral/fisiopatologia , Metabolismo Energético/fisiologia , Espaço Extracelular/metabolismo , Hipóxia Encefálica/metabolismo , Animais , Difusão , Modelos Animais de Doenças , Regulação para Baixo/fisiologia , Glucose/análise , Glucose/metabolismo , Ácido Glutâmico/análise , Ácido Glutâmico/metabolismo , Hipóxia Encefálica/fisiopatologia , Ácido Láctico/análise , Ácido Láctico/metabolismo , Masculino , Microdiálise , Neuroglia/metabolismo , Neurônios/metabolismo , Ácido Pirúvico/análise , Ácido Pirúvico/metabolismo , Ratos , Ratos Wistar , Recuperação de Função Fisiológica/fisiologia , Regulação para Cima/fisiologia
8.
Neurosci Lett ; 404(1-2): 137-42, 2006 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-16759801

RESUMO

It has been shown that global anoxia leads to dramatic changes in the diffusion properties of the extracellular space (ECS). In this study, we investigated how changes in ECS volume and geometry in the rat somatosensory cortex during and after transient hypoxia/ischemia correlate with extracellular concentrations of energy-related metabolites and glutamate. Adult male Wistar rats (n = 12) were anesthetized and subjected to hypoxia/ischemia for 30 min (ventilation with 10% oxygen and unilateral carotid artery occlusion). The ECS diffusion parameters, volume fraction and tortuosity, were determined from concentration-time profiles of tetramethylammonium applied by iontophoresis. Concentrations of lactate, glucose, pyruvate and glutamate in the extracellular fluid (ECF) were monitored by microdialysis (n = 9). During hypoxia/ischemia, the ECS volume fraction decreased from initial values of 0.19 +/- 0.03 (mean +/- S.E.M.) to 0.07 +/- 0.01 and tortuosity increased from 1.57 +/- 0.01 to 1.88 +/- 0.03. During reperfusion the volume fraction returned to control values within 20 min and then increased to 0.23 +/- 0.01, while tortuosity only returned to original values (1.53 +/- 0.06). The concentrations of lactate and glutamate, and the lactate/pyruvate ratio, substantially increased during hypoxia/ischemia, followed by continuous recovery during reperfusion. The glucose concentration decreased rapidly during hypoxia/ischemia with a subsequent return to control values within 20 min of reperfusion. We conclude that transient hypoxia/ischemia causes similar changes in ECS diffusion parameters as does global anoxia and that the time course of the reduction in ECS volume fraction correlates with the increase of extracellular concentration of glutamate. The decrease in the ECS volume fraction can therefore contribute to an increased accumulation of toxic metabolites, which may aggravate functional deficits and lead to damage of the central nervous system (CNS).


Assuntos
Córtex Cerebral/fisiopatologia , Metabolismo Energético , Ácido Glutâmico/metabolismo , Hipóxia-Isquemia Encefálica/fisiopatologia , Animais , Córtex Cerebral/metabolismo , Modelos Animais de Doenças , Espaço Extracelular/metabolismo , Glucose/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Cinética , Ácido Láctico/metabolismo , Masculino , Microdiálise , Ácido Pirúvico/metabolismo , Ratos , Ratos Wistar
9.
Cell Transplant ; 15(8-9): 675-87, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17269439

RESUMO

Stem cell transplants into spinal cord lesions may help to improve regeneration and spinal cord function. Clinical studies are necessary for transferring preclinical findings from animal experiments to humans. We investigated the transplantation of unmanipulated autologous bone marrow in patients with transversal spinal cord injury (SCI) with respect to safety, therapeutic time window, implantation strategy, method of administration, and functional improvement. We report data from 20 patients with complete SCI who received transplants 10 to 467 days postinjury. The follow-up examinations were done at 3, 6, and 12 months after implantation by two independent neurologists using standard neurological classification of SCI, including the ASIA protocol, the Frankel score, the recording of motor and somatosensory evoked potentials, and MRI evaluation of lesion size. We compared intra-arterial (via catheterization of a. vertebralis) versus intravenous administration of all mononuclear cells in groups of acute (10-30 days post-SCI, n=7) and chronic patients (2-17 months postinjury, n=13). Improvement in motor and/or sensory functions was observed within 3 months in 5 of 6 patients with intra-arterial application, in 5 of 7 acute, and in 1 of 13 chronic patients. Our case study shows that the implantation of autologous bone marrow cells appears to be safe, as there have been no complications following implantation to date (11 patients followed up for more than 2 years), but longer follow-ups are required to determine that implantation is definitively safe. Also, we cannot yet confirm that the observed beneficial effects were due to the cell therapy. However, the outcomes following transplantation in acute patients, and in one chronic patient who was in stable condition for several months prior to cell implantation, are promising. It is evident that transplantation within a therapeutic window of 3-4 weeks following injury will play an important role in any type of stem cell SCI treatment. Trials involving a larger population of patients and different cell types are needed before further conclusions can be drawn.


Assuntos
Transplante de Medula Óssea/métodos , Traumatismos da Medula Espinal/cirurgia , Doença Aguda , Adulto , Doença Crônica , Eletrofisiologia , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Regeneração Nervosa/fisiologia , Recuperação de Função Fisiológica/fisiologia , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/fisiopatologia , Transplante Autólogo
10.
Glia ; 42(1): 77-88, 2003 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-12594739

RESUMO

Tumor cell migration through the extracellular space (ECS) might be affected by its pore size and extracellular matrix molecule content. ECS volume fraction alpha (alpha = ECS volume/total tissue volume), tortuosity lambda (lambda(2) = free/apparent diffusion coefficient) and nonspecific uptake k' were studied by the real-time tetramethylammonium method in acute slices of human tissue. The diffusion parameters in temporal cortical tissue resected during surgical treatment of temporal lobe epilepsy (control) were compared with those in brain tumors. Subsequently, tumor slices were histopathologically classified according to the grading system of the World Health Organization (WHO), and proliferative activity was assessed. The average values of alpha, lambda, and k' in control cortex were 0.24, 1.55, and 3.66 x 10(-3)s(-1), respectively. Values of alpha, lambda, and k' in oligodendrogliomas did not significantly differ from controls. In pilocytic astrogliomas (WHO grade I) as well as in ependymomas (WHO grade II), alpha was significantly higher, while lambda and k' were unchanged. Higher values of alpha as well as lambda were found in low-grade diffuse astrocytomas (WHO grade II). In cellular regions of high-grade astrocytomas (WHO grade III and IV), alpha and lambda were further increased, and k' was significantly larger than in controls. Classic medulloblastomas (WHO grade IV) had an increased alpha, but not lambda or k', while in the desmoplastic type alpha and k' remained unchanged, but lambda was greatly increased. Tumor malignancy grade strongly corresponds to an increase in ECS volume, which is accompanied by a change in ECS structure manifested by an increase in diffusion barriers for small molecules.


Assuntos
Espaço Extracelular/metabolismo , Glioma/metabolismo , Glioma/patologia , Adolescente , Adulto , Idoso , Análise de Variância , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Córtex Cerebral/citologia , Córtex Cerebral/metabolismo , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Iontoforese/métodos , Masculino , Pessoa de Meia-Idade
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