Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
1.
Biomed Opt Express ; 13(4): 2091-2102, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35519259

RESUMO

A technology capable of high-resolution, label-free imaging of subtle pathology in vivo during colonoscopy is imperative for the early detection of disease and the performance of accurate biopsies. While colonoscopic OCT has been developed to visualize colonic microstructures beyond the mucosal surface, its clinical potential remains limited by sub-optimal resolution (∼6.5 µm in tissue), inadequate imaging contrast, and a lack of high-resolution OCT criteria for lesion detection. In this study, we developed an ultrahigh-resolution (UHR) colonoscopic OCT and evaluated its ability to volumetrically visualize and identify the pathological features of inflammatory bowel disease (IBD) in a rat model. Owing to its improved resolution (∼1.7 µm in tissue) and enhanced contrast, UHR colonoscopic OCT can accurately delineate fine colonic microstructures and identify the pathophysiological characteristics of IBD in vivo. By using a quantitative optical attenuation map, UHR colonoscopic OCT is able to differentiate diseased tissue (such as crypt distortion and microabscess) from normal colonic mucosa over a large field of view in vivo. Our results suggest the clinical potential of UHR colonoscopic OCT for in vivo assessment of IBD pathology.

2.
Bioeng Transl Med ; 7(1): e10259, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35079634

RESUMO

Cardiac arrest (CA), the sudden cessation of effective cardiac pumping function, is still a major clinical problem with a high rate of early and long-term mortality. Post-cardiac arrest syndrome (PCAS) may be related to an early systemic inflammatory response leading to exaggerated and sustained neuroinflammation. Therefore, early intervention with targeted drug delivery to attenuate neuroinflammation may greatly improve therapeutic outcomes. Using a clinically relevant asphyxia CA model, we demonstrate that a single (i.p.) dose of dendrimer-N-acetylcysteine conjugate (D-NAC), can target "activated" microglial cells following CA, leading to an improvement in post-CA survival rate compared to saline (86% vs. 45%). D-NAC treatment also significantly improved gross neurological score within 4 h of treatment (p < 0.05) and continued to show improvement at 48 h (p < 0.05). Specifically, there was a substantial impairment in motor responses after CA, which was subsequently improved with D-NAC treatment (p < 0.05). D-NAC also mitigated hippocampal cell density loss seen post-CA in the CA1 and CA3 subregions (p < 0.001). These results demonstrate that early therapeutic intervention even with a single D-NAC bolus results in a robust sustainable improvement in long-term survival, short-term motor deficits, and neurological recovery. Our current work lays the groundwork for a clinically relevant therapeutic approach to treating post-CA syndrome.

3.
Neurocrit Care ; 37(1): 60-72, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35072925

RESUMO

BACKGROUND: Cerebral blood flow (CBF) plays an important role in neurological recovery after cardiac arrest (CA) resuscitation. However, the variations of CBF recovery in distinct brain regions and its correlation with neurologic recovery after return of spontaneous circulation (ROSC) have not been characterized. This study aimed to investigate the characteristics of regional cerebral reperfusion following resuscitation in predicting neurological recovery. METHODS: Twelve adult male Wistar rats were studied, ten resuscitated from 7-min asphyxial CA and two uninjured rats, which were designated as healthy controls (HCs). Dynamic changes in CBF in the cerebral cortex, hippocampus, thalamus, brainstem, and cerebellum were assessed by pseudocontinuous arterial spin labeling magnetic resonance imaging, starting at 60 min after ROSC to 156 min (or time to spontaneous arousal). Neurologic outcomes were evaluated by the neurologic deficit scale at 24 h post-ROSC in a blinded manner. Correlations between regional CBF (rCBF) and neurological recovery were undertaken. RESULTS: All post-CA animals were found to be nonresponsive during the 60-156 min post ROSC, with reductions in rCBF by 24-42% compared with HC. Analyses of rCBF during the post-ROSC time window from 60 to 156 min showed the rCBF recovery of hippocampus and thalamus were positively associated with better neurological outcomes (rs = 0.82, p = 0.004 and rs = 0.73, p < 0.001, respectively). During 96 min before arousal, thalamic and cortical rCBF exhibited positive correlations with neurological recovery (rs = 0.80, p < 0.001 and rs = 0.65, p < 0.001, respectively); for predicting a favorable neurological outcome, the thalamic rCBF threshold was above 50.84 ml/100 g/min (34% of HC) (area under the curve of 0.96), whereas the cortical rCBF threshold was above 60.43 ml/100 g/min (38% of HC) (area under the curve of 0.88). CONCLUSIONS: Early magnetic resonance imaging analyses showed early rCBF recovery in thalamus, hippocampus, and cortex post ROSC was positively correlated with neurological outcomes at 24 h. Our findings suggest new translational insights into the regional reperfusion and the time window that may be critical in neurological recovery and warrant further validation.


Assuntos
Reanimação Cardiopulmonar , Parada Cardíaca , Animais , Reanimação Cardiopulmonar/métodos , Circulação Cerebrovascular/fisiologia , Parada Cardíaca/terapia , Masculino , Ratos , Ratos Wistar , Reperfusão , Roedores
4.
Sci Rep ; 11(1): 8284, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33859347

RESUMO

Patients with ulcerative colitis are typically suspected of an inflammatory flare based on suggestive symptoms of inflammation. The aim of this study was to evaluate the impact of inflammation on colonic motility and rectal sensitivity from active to recovery of inflammation. Male rats were given drinking water with 5% dextran sulfate sodium for 7 days. Inflammation, intestinal motor and sensory functions were investigated weekly for 6 weeks. (1) The disease activity index score, fecal calprotectin and tumor necrosis factor alpha were increased from Day 0 to Day 7 (active inflammation) and then decreased gradually until recovery. (2) Distal colon transit was accelerated on Day 7, and then remained unchanged. Whole gut transit was delayed on Day 7 but accelerated from Day 14 to Day 42. (3) Rectal compliance was unaffected from Day 0 to Day 7, but decreased afterwards. (4) Rectal hypersensitivity was noted on Day 7 and persistent. (5) Plasma acetylcholine was decreased on Day 7 but increased from Day 14 to Day 42. Nerve growth factor was increased from Day 7 to Day 42. DSS-induced inflammation leads to visceral hypersensitivity that is sustained until the resolution of inflammation, probably mediated by NGF. Rectal compliance is reduced one week after the DSS-induced inflammation and the reduction is sustained until the resolution of inflammation. Gastrointestinal transit is also altered during and after active colonic inflammation.


Assuntos
Colite Ulcerativa/fisiopatologia , Trânsito Gastrointestinal , Reto/fisiopatologia , Sensação , Acetilcolina/sangue , Animais , Colite Ulcerativa/metabolismo , Modelos Animais de Doenças , Fezes/química , Inflamação , Complexo Antígeno L1 Leucocitário/metabolismo , Masculino , Fator de Crescimento Neural/metabolismo , Ratos , Recuperação de Função Fisiológica , Índice de Gravidade de Doença , Fatores de Tempo , Fator de Necrose Tumoral alfa/metabolismo
5.
Neurogastroenterol Motil ; 32(10): e13916, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32537873

RESUMO

BACKGROUND: The mucosal barrier damage is recognized as one of the key factors in the pathogenesis of colitis. While sacral nerve stimulation (SNS) was reported to have therapeutic potential for colitis, its mechanisms of actions on colonic permeability remained largely unknown. METHODS: In this study, colitis was induced by intrarectal administration of TNBS in rats. Five days later, they were treated with SNS or sham-SNS for 10 days. The effects of SNS on colonic permeability were assessed by measuring the expression of tight-junction proteins involved in regulating permeability and the FITC-dextran test. The mechanism of actions of SNS was investigated by studying the function of the enteric nervous system (ENS) cells and analyzing the autonomic nervous system. KEY RESULTS: SNS decreased the disease activity index, microscopic and macroscopic scores, myeloperoxidase activity, and pro-inflammatory cytokines (TNF-α, IL-6). SNS increased the expression of Zonula Occludens-1, Occludin, Claudin-1, and Junctional adhesion molecule-A in the colon tissue. The FITC-dextran test showed that the colonic permeability was lower with SCS than sham-SNS. SNS increased ChAT, pancreatic polypeptide, and GDNF and reduced norepinephrine NGF, sub-P, and mast cell overactivation in the colon tissue. Concurrently, SNS increased acetylcholine in colon tissues and elevated vagal efferent activity. CONCLUSIONS & INFERENCES: SNS ameliorates colonic inflammation and enhances colonic barrier function with the proposed mechanisms involving the increase in parasympathetic activity and modulation of the activity of the ENS and immune system, including mast cells.


Assuntos
Colite/fisiopatologia , Colite/terapia , Modelos Animais de Doenças , Terapia por Estimulação Elétrica/tendências , Plexo Lombossacral/fisiologia , Animais , Colite/induzido quimicamente , Terapia por Estimulação Elétrica/instrumentação , Eletrodos Implantados/tendências , Plexo Lombossacral/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley , Roedores , Ácido Trinitrobenzenossulfônico/toxicidade
6.
Obes Surg ; 29(9): 2869-2877, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31222497

RESUMO

BACKGROUND: Vagal nerve stimulation (VNS) has been reported to reduce body weight and improve sympathovagal imbalance in both basic and clinical studies. Its effects on glycemic control were however unclear. The aims of this study were to investigate the effects of VNS with various parameters on blood glucose and its possible mechanisms in rats. METHODS: A hyperglycemic rodent model induced by glucagon was used initially to optimize the VNS parameters; then, a type 2 diabetic rodent model induced by high-fat diet combined with streptozotocin was used to validate the VNS method. The VNS electrodes were implanted at the dorsal subdiaphragmatic vagus; three subcutaneous electrodes were implanted at the chest area for recording electrocardiogram in rats induced by glucagon. RESULTS: (1) VNS with short pulse width of 0.3 ms but not 3 ms reduced blood glucose during an oral glucose tolerance test (OGTT), with a 38.4% reduction at 15 min and 26.9% at 30 min (P < 0.05, vs. sham-VNS respectively). (2) VNS at low frequency of 5 Hz but not 14 Hz or 40 Hz reduced blood glucose during the OGTT (P < 0.05, vs. sham-VNS). (3) Intermittent VNS was more potent than continuous VNS (P < 0.01). (4) No difference was found between unilateral VNS and bilateral VNS. (5) VNS enhanced vagal activity (P = 0.005). (6) The hypoglycemic effect of VNS was blocked by glucagon-like peptide-1 (GLP-1) antagonist exendin-4. CONCLUSIONS: VNS at 5 Hz reduces blood glucose in diabetic rats by enhancing vagal efferent activity and the release of GLP-1.


Assuntos
Glicemia/fisiologia , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Estimulação do Nervo Vago , Animais , Glicemia/análise , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/terapia , Ratos
7.
Brain Res ; 1682: 1-13, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29277709

RESUMO

Granulocyte-colony stimulating factor (G-CSF) is an endogenous growth factor that exhibits a diverse range of neuroprotective mechanisms against a variety of neurological disorders including ischemic stroke. We investigated the anti-apoptotic mechanisms of G-CSF against endoplasmic reticulum (ER) stress induced apoptosis. Sprague-Dawley rats were subjected to transient occlusion of the middle cerebral artery (MCAO) for 90 min. Rats were injected with G-CSF (n = 15; 50 µg/kg body weight s.c.) for 4 days, starting 24 h post-MCAO and brains were harvested after 4 days reperfusion (n = 16). Key proteins in ER stress apoptosis were analyzed by immunoblotting. G-CSF reduced infarct volume to 53% and improved neurological deficits. G-CSF treatment significantly (P < .05) attenuated the expression of proteins involved in ER stress apoptosis pathway; ATF4, ATF6, p-p38MAPK, pJNK and CHOP. G-CSF treatment also re-established ER homeostasis evident by the reduction of the intraluminal ER stress sensor, GRP78 as well as reducing the overall cellular stress level protein, HSP27. G-CSF also up-regulated anti-apoptotic proteins pAKT and Bcl-2 while down-regulated the pro-apoptotic protein Bax. G-CSF exerts neuroprotection from cerebral ischemia through the preservation of the ER, resulting in the attenuation of pro-apoptotic proteins and the potentiation of anti-apoptotic proteins.


Assuntos
Estresse do Retículo Endoplasmático/efeitos dos fármacos , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/fisiopatologia , Fármacos Neuroprotetores/uso terapêutico , Fator 6 Ativador da Transcrição/metabolismo , Análise de Variância , Animais , Apoptose/efeitos dos fármacos , Infarto Encefálico/etiologia , Ciclina D1/metabolismo , Modelos Animais de Doenças , Masculino , Exame Neurológico , Fosfopiruvato Hidratase/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Fator Estimulador de Colônias de Granulócitos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína X Associada a bcl-2/metabolismo
8.
Adv Exp Med Biol ; 975 Pt 1: 207-216, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28849456

RESUMO

Ischemic stroke is one of the greatest contributors to death and long term disability in developed countries. Ischemia induced brain injury arises due to excessive release of glutamate and involves cell death due to apoptosis and endoplasmic reticulum (ER) stress responses. Despite major research efforts there are currently no effective treatments for stroke. Taurine, a free amino acid found in high concentrations in many invertebrate and vertebrate systems can provide protection against a range of neurological disorders. Here we demonstrate that taurine can combat ER stress responses induced by glutamate or by hypoxia/re-oxygenation in neuronal cell lines and primary neuronal cultures. Taurine decreased expression of ER stress markers GRP78, CHOP, Bim and caspase 12 in primary neuronal cultures exposed to hypoxia/re-oxygenation. In analyzing individual ER stress pathways we demonstrated that taurine treatment can result in reduced levels of cleaved ATF6 and decreased p-IRE1 levels. We hypothesized that because of the complex nature of stroke a combination therapy approach may be optimal. For this reason we proceeded to test combination therapies using taurine plus low dose administration of an additional drug: either granulocyte colony stimulating factor (G-CSF) or sulindac a non-steroidal anti-inflammatory drug with potent protective functions through signaling via ischemic preconditioning pathways. When primary neurons were pretreated with 25 mM taurine and 25 ng/mL G-CSF for I hour and then exposed to high levels of glutamate, the taurine/G-CSF combination increased the protective effect against glutamate toxicity to 88% cell survival compared to 75% cell survival from an individual treatment with taurine or G-CSF alone. Pre-exposure of PC12 cells to 5 mM taurine or 25 µM sulindac did not protect the cells from hypoxia/re-oxygenation stress whereas at these concentrations the combination of taurine plus sulindac provided significant protection. In summary we have demonstrated the protective effect of taurine in primary neuronal cultures against hypoxia with re-oxygenation through inhibition of ATF6 or p-IRE-1 pathway but not the PERK pathway of ER stress. Furthermore the combinations of taurine plus an additional drug (either G-CSF or sulindac) can show enhanced potency for protecting PC 12 cells from glutamate toxicity or hypoxia/re-oxygenation through inhibition of ER stress responses.


Assuntos
Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Taurina/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Ácido Glutâmico/toxicidade , Fator Estimulador de Colônias de Granulócitos/farmacologia , Células PC12 , Ratos , Traumatismo por Reperfusão , Sulindaco/farmacologia
9.
Sci Rep ; 7(1): 6743, 2017 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-28751716

RESUMO

The cellular-level effects of low/high frequency oscillating magnetic field on excitable cells such as neurons are well established. In contrast, the effects of a homogeneous, static magnetic field (SMF) on Central Nervous System (CNS) glial cells are less investigated. Here, we have developed an in vitro SMF stimulation set-up to investigate the genomic effects of SMF exposure on oligodendrocyte differentiation and neurotrophic factors secretion. Human oligodendrocytes precursor cells (OPCs) were stimulated with moderate intensity SMF (0.3 T) for a period of two weeks (two hours/day). The differential gene expression of cell activity marker (c-fos), early OPC (Olig1, Olig2. Sox10), and mature oligodendrocyte markers (CNP, MBP) were quantified. The enhanced myelination capacity of the SMF stimulated oligodendrocytes was validated in a dorsal root ganglion microfluidics chamber platform. Additionally, the effects of SMF on the gene expression and secretion of neurotrophic factors- BDNF and NT3 was quantified. We also report that SMF stimulation increases the intracellular calcium influx in OPCs as well as the gene expression of L-type channel subunits-CaV1.2 and CaV1.3. Our findings emphasize the ability of glial cells such as OPCs to positively respond to moderate intensity SMF stimulation by exhibiting enhanced differentiation, functionality as well as neurotrophic factor release.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Cálcio/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Campos Magnéticos , Proteína Básica da Mielina/metabolismo , Oligodendroglia/metabolismo , 2',3'-Nucleotídeo Cíclico 3'-Fosfodiesterase/genética , 2',3'-Nucleotídeo Cíclico 3'-Fosfodiesterase/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Biomarcadores/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Canais de Cálcio Tipo L/genética , Canais de Cálcio Tipo L/metabolismo , Diferenciação Celular , Embrião de Mamíferos , Gânglios Espinais/citologia , Gânglios Espinais/metabolismo , Regulação da Expressão Gênica , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Técnicas Analíticas Microfluídicas , Proteína Básica da Mielina/genética , Fatores de Crescimento Neural/genética , Fatores de Crescimento Neural/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Neurotrofina 3 , Fator de Transcrição 2 de Oligodendrócitos/genética , Fator de Transcrição 2 de Oligodendrócitos/metabolismo , Oligodendroglia/citologia , Cultura Primária de Células , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Ratos Sprague-Dawley , Fatores de Transcrição SOXE/genética , Fatores de Transcrição SOXE/metabolismo
10.
Regen Med ; 11(2): 181-91, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26857809

RESUMO

Rapid progress in the field of stem cell therapy and cellular reprogramming provides convincing evidence of its feasibility in treating a wide range of pathologies through autologous cell replacement therapy. This review article describes in detail on three widely used approaches of somatic cell reprogramming: induced pluripotent stem cells, direct conversion and direct reprogramming, in the context of demyelination in the CNS. The potential limitations of each reprogramming technique are reviewed along with their distinct molecular approach to reprogramming. This is followed by an analysis on the scopes and challenges of its translational applications in deriving oligodendrocyte progenitor cells and oligodendrocytes for cell replacement treatment of demyelinating conditions in the CNS.


Assuntos
Transdiferenciação Celular , Técnicas de Reprogramação Celular/métodos , Doenças Desmielinizantes/terapia , Células-Tronco Pluripotentes Induzidas , Oligodendroglia , Transplante de Células-Tronco/métodos , Animais , Autoenxertos , Humanos
11.
PLoS One ; 10(1): e0116933, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25635918

RESUMO

Induced pluripotent stem (iPS) cells are at the forefront of research in regenerative medicine and are envisaged as a source for personalized tissue repair and cell replacement therapy. Here, we demonstrate for the first time that oligodendrocyte progenitors (OPs) can be derived from iPS cells generated using either an episomal, non-integrating plasmid approach or standard integrating retroviruses that survive and differentiate into mature oligodendrocytes after early transplantation into the injured spinal cord. The efficiency of OP differentiation in all 3 lines tested ranged from 40% to 60% of total cells, comparable to those derived from human embryonic stem cells. iPS cell lines derived using episomal vectors or retroviruses generated a similar number of early neural progenitors and glial progenitors while the episomal plasmid-derived iPS line generated more OPs expressing late markers O1 and RIP. Moreover, we discovered that iPS-derived OPs (iPS-OPs) engrafted 24 hours following a moderate contusive spinal cord injury (SCI) in rats survived for approximately two months and that more than 70% of the transplanted cells differentiated into mature oligodendrocytes that expressed myelin associated proteins. Transplanted OPs resulted in a significant increase in the number of myelinated axons in animals that received a transplantation 24 h after injury. In addition, nearly a 5-fold reduction in cavity size and reduced glial scarring was seen in iPS-treated groups compared to the control group, which was injected with heat-killed iPS-OPs. Although further investigation is needed to understand the mechanisms involved, these results provide evidence that patient-specific, iPS-derived OPs can survive for three months and improve behavioral assessment (BBB) after acute transplantation into SCI. This is significant as determining the time in which stem cells are injected after SCI may influence their survival and differentiation capacity.


Assuntos
Células-Tronco Pluripotentes Induzidas/transplante , Células-Tronco Neurais/transplante , Traumatismos da Medula Espinal/terapia , Animais , Axônios/fisiologia , Diferenciação Celular , Sobrevivência Celular , Células Cultivadas , Intervenção Médica Precoce , Feminino , Humanos , Atividade Motora , Bainha de Mielina/fisiologia , Regeneração Nervosa , Oligodendroglia/fisiologia , Ratos Endogâmicos Lew , Recuperação de Função Fisiológica , Medula Espinal/patologia , Medula Espinal/fisiopatologia , Resultado do Tratamento
12.
Brain Res ; 1576: 91-9, 2014 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-24968090

RESUMO

BACKGROUND AND PURPOSE: The present study analyzed whether administration of sulindac, a non-steroidal anti-inflammatory drug (NSAID) would prevent, attenuate or repair ischemia induced brain injury and reverse functional impairment in a focal ischemia model of stroke. METHODS: Male Sprague-Dawley rats (weight 250-300 g) were subjected to middle cerebral artery occlusion (MCAO). Sulindac was given 2 days before and 24 h after ischemia at 0.2 mg/day with daily injections until sacrifice on day 3 or day 11. Infarct size was measured by TTC staining and western immunoblot was employed. RESULTS: TTC analysis of brain slices indicated a decrease in infarct size in sulindac treated animals. Western blot results indicated that sulindac induced expression of Hsp 27, a marker of cell stress, in the ischemic penumbra and core on days 3 and 11. Hsp 27 is important as a protective molecular chaperone. Increases were also found in the protective molecules Akt and Bcl-2 in the ischemic penumbra and core following sulindac administration. CONCLUSION: Our data indicate that administration of sulindac results in decreased infarct size and that there is a central role for the molecular chaperone Hsp 27, the pro-survival kinase Akt and the anti-apoptotic component Bcl-2 in mediating these protective effects.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Infarto da Artéria Cerebral Média/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Sulindaco/uso terapêutico , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Sobrevivência Celular , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico HSP27/biossíntese , Proteínas de Choque Térmico HSP27/genética , Proteínas de Choque Térmico/biossíntese , Proteínas de Choque Térmico/genética , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/patologia , Masculino , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Fármacos Neuroprotetores/farmacologia , Pré-Medicação , Proteínas Proto-Oncogênicas c-akt/biossíntese , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/genética , Ratos , Ratos Sprague-Dawley , Sulindaco/farmacologia , Regulação para Cima
13.
Cytotherapy ; 15(9): 1073-85, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23806239

RESUMO

BACKGROUND AIMS: Cell therapy is considered a promising option for treatment of spinal cord injury (SCI). The purpose of this study is to use combined therapy of bone marrow stromal cells (BMSCs) and BMSC-derived gamma-aminobutyric acid (GABA)ergic inhibitory neurotransmitter cells (BDGCs) for the contusion model of SCI in rats. METHODS: BDGCs were prepared from BMSCs by pre-inducing them with ß-mercaptoethanol followed by retinoic acid and then inducing them by creatine. They were immunostained with BMSC, proneuronal, neural and GABA markers. The BDGCs were intraspinally transplanted into the contused rats, whereas the BMSCs were delivered intravenously. The animals were sacrificed after 12 weeks. RESULTS: The Basso, Beattie and Bresnahan test showed improvement in the animals with the combined therapy compared with the untreated animals, the animals treated with GABAergic cells only and the animals that received BMSCs. The immunohistochemistry analysis of the tissue sections prepared from the animals receiving the combined therapy showed that the transplanted cells were engrafted and integrated into the injured spinal cord; in addition, a significant reduction was seen in the cavitation. CONCLUSIONS: The study shows that the combination of GABAergic cells with BMSCs can improve SCI.


Assuntos
Células-Tronco Mesenquimais/fisiologia , Traumatismos da Medula Espinal/terapia , Ácido gama-Aminobutírico/farmacologia , Animais , Transplante de Medula Óssea/métodos , Feminino , Regeneração Nervosa/fisiologia , Neurotransmissores/metabolismo , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/fisiologia
14.
Adv Exp Med Biol ; 775: 167-75, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23392933

RESUMO

Stroke is one of the leading causes of mortality and disability worldwide. There is no effective treatment for stroke despite extensive research. Taurine is a free amino acid which is present at high concentrations in a range of organs including the brain, heart, and retina in mammalian systems. It had been shown that taurine can significantly increase cell survival under stroke conditions using both in vivo and in vitro models. Recently, we have found that several agents including granulocyte colony-stimulating factor (G-CSF), a stem cell enhancer and facilitator;S-methyl-N-diethylthiolcarbamate sulfoxide (DETC-MeSO), an NMDA receptor partial antagonist; sulindac, a potent antioxidant; and taurine, a neuroprotectant and calcium regulator, are effective in protecting against stroke-induced neuronal injury when used alone or in combination in both animal and tissue/cell culture models. In this chapter, we demonstrate that taurine can protect human neuroblastoma cells measured by ATP assay under conditions of hypoxia or oxygen/glucose deprivation (OGD). In addition, we found that taurine exerts its protective function by suppressing the OGD-induced upregulation of endoplasmic reticulum (ER) stress markers and proapoptotic proteins. A model depicting the mode of action of taurine in protecting neuroblastoma cells under OGD conditions is presented.


Assuntos
Citoproteção/efeitos dos fármacos , Glucose/deficiência , Neuroblastoma/patologia , Fármacos Neuroprotetores/farmacologia , Oxigênio/metabolismo , Taurina/farmacologia , Fator 4 Ativador da Transcrição/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Hipóxia Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Proteínas de Ligação a DNA/metabolismo , Endorribonucleases/metabolismo , Fator de Iniciação 2 em Eucariotos/metabolismo , Humanos , Proteínas de Membrana/metabolismo , Modelos Biológicos , Neuroblastoma/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Proteína Fosfatase 1 , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Fatores de Transcrição de Fator Regulador X , Estresse Fisiológico/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Células Tumorais Cultivadas
15.
Restor Neurol Neurosci ; 30(6): 511-25, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22903159

RESUMO

PURPOSE: Deficits involving GABAergic neurons have been reported in aging, central nervous trauma and neurodegenerative disorders; bone marrow stromal cells (BMSCs) have been proposed as a feasible source of donor cells in replacement cell therapy. In this study, the effects of creatine on transdifferentiating BMSCs into GABAergic-like neurons were evaluated in vitro. METHODS: The BMSCs were isolated from adult rats, preinduced by ß-mercaptoethanol (BME) and retinoic acid (RA), and then induced by creatine into GABAergic-like neurons. The cells were characterized using different differentiation markers. The functionality of the differentiated cells was evaluated using FM1-43. RESULTS: The isolated cells expressed Oct-4 and were immunoreactive to fibronectin and CD44. The highest percentages of cells immunoreactive to nestin and neurofilament-68 were found at the second day of preinduction. At the induction stage, there were increases in the number of cells immunoreactive to neurofilament-200, MAP-2, synapsin I, synaptophysin, and NeuN. The percentages of the immunoreactive cells to GABAergic neuron markers increased. The optimal induction dose was 5 mM. The dose of 10 mM showed a decline in the expression of most of these markers. The functionality test indicated that the synaptic vesicles were released upon stimulation. CONCLUSION: Creatine can induce the differentiation of BMSCs to the GABAergic neuronal phenotype within one week.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Creatina/farmacologia , Neurônios GABAérgicos/citologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Neurais/citologia , Animais , Biomarcadores/metabolismo , Diferenciação Celular/fisiologia , Células Cultivadas , Relação Dose-Resposta a Droga , Neurônios GABAérgicos/metabolismo , Imunofenotipagem , Técnicas In Vitro , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Neurais/metabolismo , Ratos , Ratos Sprague-Dawley , Vesículas Sinápticas/metabolismo
16.
Restor Neurol Neurosci ; 28(3): 367-77, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20479529

RESUMO

Bone marrow stromal cells (BMSCs) are multipotent and can be induced to differentiate into different lineages including osteogenic, chondrogenic, myogenic and neuronal phenotypes. BMSCs were reported to be a suitable option for regenerative medical research. In this study, BMSCs were induced into GABAergic phenotypes using beta-mercaptoethanol (betaME) and retinoic acid (RA) as preinducers followed by potassium chloride as inducer, and were evaluated by fibronectin and Oct-4. The percentages of cells immunoreactive for nestin, neurofilaments (NF 68, NF 160, and NF 200), GABA and GABA synthesizing and packaging enzymes (GAD1, GAD2, VGAT) were used for evaluating GABAergic differentiation. RT-PCR was used for confirming the expression of these enzymes. The differentiated cells were loaded and unloaded with FM1-43 in order to assess the functionality of the cells. At the preinduction stage, the cells downregulated fibronectin and Oct-4, and expressed neuronal markers. At the induction stage, the preinduced cells transdifferentiated into GABAergic cells, as confirmed by immunohistochemistry and RT-PCR. The GABAergic cells were stained and destained with FM1-43. Therefore, the two-stage induction protocol resulted in transdifferentiation of BMSCs into GABAergic cells with synaptic release upon stimulation.


Assuntos
Células da Medula Óssea/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Interneurônios/citologia , Cloreto de Potássio/farmacologia , Ácido gama-Aminobutírico/metabolismo , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Encefalopatias/metabolismo , Encefalopatias/fisiopatologia , Encefalopatias/terapia , Técnicas de Cultura de Células , Diferenciação Celular/fisiologia , Transplante de Células/métodos , Células Cultivadas , Interneurônios/metabolismo , Interneurônios/transplante , Proteínas do Tecido Nervoso/análise , Proteínas do Tecido Nervoso/metabolismo , Ratos , Ratos Sprague-Dawley , Células Estromais/citologia , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismo
17.
Iran Biomed J ; 13(3): 137-43, 2009 07.
Artigo em Inglês | MEDLINE | ID: mdl-19688019

RESUMO

BACKGROUND: Cell therapy of many neurodegenerative diseases using bone marrow stromal cells (BMSC) requires the differentiation of BMSC into neuronal subtype. However, the transdifferentiation of BMSC into GABAergic phenotype requires more investigation. METHODS: In this study, BMSC of adult female rats were pre-induced into neuroblast-like cells using 1 mM beta-mercaptoethanol (betaME) and 10 microM retinoic acid (RA), followed by 40 mM potassium chloride as inducer. The BMSC were evaluated by fibronectin as well as Oct-4. The percentage of nestin, neurofilaments (NF 68, NF 160, and NF 200) and GABA immuno-reactive cells was used to evaluate the GABAergic differentiation at the pre-induction and induction stages. The statistical analysis was carried out using unpaired student's t-test and ANOVA with Tukey's multiple comparison. RESULTS: The BMSC in the fourth passage expressed fibronectin up to 91.24 +/- 0.82%. The pre-induced cells after 2 days of RA exposure showed the expression of neuroblastic markers of nestin and NF68 (81.56 +/- 2.64% and 82.12 +/- 2.65%, respectively). The yield of GABAergic neurons with beta-ME for 1 h and RA as pre-inducer for 2 days followed by potassium chloride as inducer (40 mM for 3 days) was 60.64% +/- 1.97%. In addition, NF160 and NF200 were detected in the transdifferentiated cells. RT-PCR showed no expression of Oct-4 after the induction and pre-induction stages. CONCLUSION: GABAergic-like neurons obtained from BMSC can be potentially used in cell transplanting for some neurodegenerative disorders.


Assuntos
Células da Medula Óssea/fisiologia , Transdiferenciação Celular , Neurônios/fisiologia , Células Estromais/fisiologia , Ácido gama-Aminobutírico/metabolismo , Animais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Técnicas de Cultura de Células , Transdiferenciação Celular/efeitos dos fármacos , Transdiferenciação Celular/fisiologia , Feminino , Proteínas de Filamentos Intermediários/metabolismo , Mercaptoetanol/farmacologia , Proteínas do Tecido Nervoso/metabolismo , Nestina , Neurogênese/efeitos dos fármacos , Neurogênese/fisiologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Cloreto de Potássio/farmacologia , Ratos , Ratos Sprague-Dawley , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismo , Tretinoína/farmacologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA