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1.
Toxicol Appl Pharmacol ; 377: 114627, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31202640

RESUMO

In many neuropathologies activated microglia and macrophages cause neurotoxicity and prolong the inflammatory response. We have previously characterized the glycosphingolipid Neurostatin (Nst), which potentially reduces these detrimental mechanisms. Nst, isolated from mammalian brain, is the GD1b ganglioside with O-acetylation of the outer sialic acid residue. Using the enzyme sialate-O-acetyltransferase (SOAT), we obtained several O-acetylated gangliosides and O-propionylated GD1b (PrGD1b). In the present study we investigated the anti-inflammatory effects of these compounds. Nst and other O-acetylated gangliosides reduced nitrite production in microglial cells which were activated with lipopolysaccharide (LPS), but did not affect nitrite production after their stimulation with interferon gamma (IFNγ). Structure-activity relationship analysis showed that Nst was the most active ganglioside as inhibitor of nitrite production. Its ceramide moiety is essential for this, and both, the O-acetylation and the monosaccharide chain are important for the anti-inflammatory activity of the gangliosides. We also found that Nst reduced iNOS, IL-6 and IL-12 transcription in LPS-induced microglia, likely by inhibiting nuclear localization of NFκB. In co-cultures, Nst reduced neuronal cell death caused by LPS-activated microglia. In vivo, Nst diminished microglia activation in a mouse model of acute neuroinflammation. We propose that Nst and other O-acetylated gangliosides are neuroprotective regulators of microglia activity under both physiological and pathological conditions.


Assuntos
Anti-Inflamatórios/farmacologia , Encefalite/prevenção & controle , Gangliosídeos/farmacologia , Glicoesfingolipídeos/farmacologia , NF-kappa B/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Linhagem Celular , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Transportadores de Ânions Orgânicos/metabolismo , Ratos , Ratos Wistar
2.
J Cell Physiol ; 232(6): 1501-1510, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27753092

RESUMO

Following a central nervous system (CNS) injury, restoration of the blood-brain barrier (BBB) integrity is essential for recovering homeostasis. When this process is delayed or impeded, blood substances and cells enter the CNS parenchyma, initiating an additional inflammatory process that extends the initial injury and causes so-called secondary neuronal loss. Astrocytes and profibrotic mesenchymal cells react to the injury and migrate to the lesion site, creating a new glia limitans that restores the BBB. This process is beneficial for the resolution of the inflammation, neuronal survival, and the initiation of the healing process. Salubrinal is a small molecule with neuroprotective properties in different animal models of stroke and trauma to the CNS. Here, we show that salubrinal increased neuronal survival in the neighbourhood of a cerebral cortex stab injury. Moreover, salubrinal reduced cortical blood leakage into the parenchyma of injured animals compared with injured controls. Adjacent to the site of injury, salubrinal induced immunoreactivity for platelet-derived growth factor subunit B (PDGF-B), a specific mitogenic factor for mesenchymal cells. This effect might be responsible for the increased immunoreactivity for fibronectin and the decreased activation of microglia and macrophages in injured mice treated with salubrinal, compared with injured controls. The immunoreactivity for PDGF-B colocalized with neuronal nuclei (NeuN), suggesting that cortical neurons in the proximity of the injury were the main source of PDGF-B. Our results suggest that after an injury, neurons play an important role in both, the healing process and the restoration of the BBB integrity. J. Cell. Physiol. 232: 1501-1510, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Barreira Hematoencefálica/patologia , Lesões Encefálicas/tratamento farmacológico , Córtex Cerebral/lesões , Cinamatos/farmacologia , Neuroproteção/efeitos dos fármacos , Tioureia/análogos & derivados , Ferimentos Perfurantes/tratamento farmacológico , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos , Lesões Encefálicas/patologia , Proteínas de Ligação ao Cálcio/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Córtex Cerebral/patologia , Cinamatos/uso terapêutico , Modelos Animais de Doenças , Azul Evans/metabolismo , Fibronectinas/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Proteínas dos Microfilamentos/metabolismo , Modelos Biológicos , Neurônios/efeitos dos fármacos , Neurônios/patologia , Fator de Crescimento Derivado de Plaquetas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Tioureia/farmacologia , Tioureia/uso terapêutico , Fator de Crescimento Transformador beta/metabolismo , Ferimentos Perfurantes/patologia
3.
J Cell Physiol ; 232(8): 2231-2245, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27987324

RESUMO

Bile acids are steroid acids found in the bile of mammals. The bile acid conjugate tauroursodeoxycholic acid (TUDCA) is neuroprotective in different animal models of stroke and neurological diseases. We have previously shown that TUDCA has anti-inflammatory effects on glial cell cultures and in a mouse model of acute neuroinflammation. We show now that microglial cells (central nervous system resident macrophages) express the G protein-coupled bile acid receptor 1/Takeda G protein-coupled receptor 5 (GPBAR1/TGR5) in vivo and in vitro. TUDCA binding to GPBAR1/TGR5 caused an increase in intracellular cAMP levels in microglia that induced anti-inflammatory markers, while reducing pro-inflammatory ones. This anti-inflammatory effect of TUDCA was inhibited by small interference RNA for GPBAR1/TGR5 receptor, as well as by treatment with a protein kinase A (PKA) inhibitor. In the mouse model of acute neuroinflammation, treating the animals with TUDCA was clearly anti-inflammatory. TUDCA biased the microglial phenotype in vivo and in vitro toward the anti-inflammatory. The bile acid receptor GPBAR1/TGR5 could be a new therapeutic target for pathologies coursing with neuroinflammation and microglia activation, such as traumatic brain injuries, stroke, or neurodegenerative diseases. TUDCA and other GPBAR1/TGR5 agonists need to be further investigated, to determine their potential in attenuating the neuropathologies associated with microglia activation. J. Cell. Physiol. 232: 2231-2245, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Anti-Inflamatórios/farmacologia , Encefalite/prevenção & controle , Hipocampo/efeitos dos fármacos , Microglia/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Prosencéfalo/efeitos dos fármacos , Receptores Acoplados a Proteínas G/agonistas , Ácido Tauroquenodesoxicólico/farmacologia , Animais , Animais Recém-Nascidos , Células Cultivadas , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Modelos Animais de Doenças , Encefalite/genética , Encefalite/metabolismo , Encefalite/patologia , Hipocampo/metabolismo , Hipocampo/patologia , Mediadores da Inflamação/metabolismo , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Microglia/patologia , Prosencéfalo/metabolismo , Prosencéfalo/patologia , Inibidores de Proteínas Quinases/farmacologia , Interferência de RNA , Ratos Wistar , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Transfecção
4.
Exp Cell Res ; 335(1): 82-90, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25882497

RESUMO

After CNS injury, astrocytes and mesenchymal cells attempt to restore the disrupted glia limitans by secreting proteoglycans and extracellular matrix proteins (ECMs), forming the so-called glial scar. Although the glial scar is important in sealing the lesion, it is also a physical and functional barrier that prevents axonal regeneration. The synthesis of secretory proteins in the RER is under the control of the initiation factor of translation eIF2α. Inhibiting the synthesis of secretory proteins by increasing the phosphorylation of eIF2α, might be a pharmacologically efficient way of reducing proteoglycans and other profibrotic proteins present in the glial scar. Salubrinal, a neuroprotective drug, decreased the expression and secretion of proteoglycans and other profibrotic proteins induced by EGF or TGFß, maintaining eIF2α phosphorylated. Besides, Salubrinal also reduced the transcription of proteoglycans and other profibrotic proteins, suggesting that it induced the degradation of non-translated mRNA. In a model in vitro of the glial scar, cortical neurons grown on cocultures of astrocytes and fibroblasts with TGFß treated with Salubrinal, showed increased neurite outgrowth compared to untreated cells. Our results suggest that Salubrinal may be considered of therapeutic value facilitating axonal regeneration, by reducing overproduction and secretion of proteoglycans and profibrotic protein inhibitors of axonal growth.


Assuntos
Córtex Cerebral/fisiologia , Cinamatos/farmacologia , Proteínas da Matriz Extracelular/biossíntese , Regeneração Nervosa/efeitos dos fármacos , Neuritos/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Proteoglicanas/antagonistas & inibidores , Tioureia/análogos & derivados , Animais , Astrócitos/metabolismo , Células Cultivadas , Córtex Cerebral/lesões , Técnicas de Cocultura , Fibroblastos/metabolismo , Técnicas In Vitro , Camundongos , Camundongos Endogâmicos C57BL , Neuritos/fisiologia , Neuroglia/metabolismo , Fosforilação , Cultura Primária de Células , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Proteoglicanas/biossíntese , RNA Mensageiro/metabolismo , Tioureia/farmacologia , Fator de Crescimento Transformador beta/farmacologia
5.
J Neuroinflammation ; 11: 50, 2014 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-24645669

RESUMO

BACKGROUND: Bile acids are steroid acids found predominantly in the bile of mammals. The bile acid conjugate tauroursodeoxycholic acid (TUDCA) is a neuroprotective agent in different animal models of stroke and neurological diseases. However, the anti-inflammatory properties of TUDCA in the central nervous system (CNS) remain unknown. METHODS: The acute neuroinflammation model of intracerebroventricular (icv) injection with bacterial lipopolysaccharide (LPS) in C57BL/6 adult mice was used herein. Immunoreactivity against Iba-1, GFAP, and VCAM-1 was measured in coronal sections in the mice hippocampus. Primary cultures of microglial cells and astrocytes were obtained from neonatal Wistar rats. Glial cells were treated with proinflammatory stimuli to determine the effect of TUDCA on nitrite production and activation of inducible enzyme nitric oxide synthase (iNOS) and NFκB luciferase reporters. We studied the effect of TUDCA on transcriptional induction of iNOS and monocyte chemotactic protein-1 (MCP-1) mRNA as well as induction of protein expression and phosphorylation of different proteins from the NFκB pathway. RESULTS: TUDCA specifically reduces microglial reactivity in the hippocampus of mice treated by icv injection of LPS. TUDCA treatment reduced the production of nitrites by microglial cells and astrocytes induced by proinflammatory stimuli that led to transcriptional and translational diminution of the iNOS. This effect might be due to inhibition of the NFκB pathway, activated by proinflammatory stimuli. TUDCA decreased in vitro microglial migration induced by both IFN-γ and astrocytes treated with LPS plus IFN-γ. TUDCA inhibition of MCP-1 expression induced by proinflammatory stimuli could be in part responsible for this effect. VCAM-1 inmunoreactivity in the hippocampus of animals treated by icv LPS was reduced by TUDCA treatment, compared to animals treated with LPS alone. CONCLUSIONS: We show a triple anti-inflammatory effect of TUDCA on glial cells: i) reduced glial cell activation, ii) reduced microglial cell migratory capacity, and iii) reduced expression of chemoattractants (e.g., MCP-1) and vascular adhesion proteins (e.g., VCAM-1) required for microglial migration and blood monocyte invasion to the CNS inflammation site. Our results present a novel TUDCA anti-inflammatory mechanism, with therapeutic implications for inflammatory CNS diseases.


Assuntos
Colagogos e Coleréticos/farmacologia , Encefalite/patologia , Hipocampo/patologia , Neuroglia/efeitos dos fármacos , Ácido Tauroquenodesoxicólico/farmacologia , Animais , Animais Recém-Nascidos , Proteínas de Ligação ao Cálcio/metabolismo , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Encefalite/induzido quimicamente , Regulação da Expressão Gênica/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/metabolismo , Injeções Intraventriculares , Lipopolissacarídeos/toxicidade , Camundongos Endogâmicos C57BL , Proteínas dos Microfilamentos/metabolismo , Nitritos/metabolismo , Ratos Wistar , Molécula 1 de Adesão de Célula Vascular/metabolismo
6.
Bioorg Med Chem Lett ; 23(2): 435-9, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23245511

RESUMO

Neurostatin, a natural glycosphingolipid, and NF115, a synthetic glycolipid, are inhibitors of glioma growth. While neurostatin shows high inhibitory activity on gliomas its abundance is low in mammalian brain. On the contrary NF115 exhibits less inhibitory activity on gliomas, but could be prepared by chemical synthesis. In this study we describe synthetic compounds, structurally related to NF115, capable of inhibiting glioma growth at low micromolar range. We used DNA microarray technology to compare the genes inhibited in U373-MG human glioma cells after treatment with the natural or synthetic inhibitor. New synthetic compounds were developed to interact with the product of Rho GDP dissociation inhibitor alpha gene, which was repressed in both treatments. Compounds that were inhibitors of glioma cell growth in assays for [3H]-thymidine incorporation were then injected in C6 tumor bearing rats and the tumor size in each animal group were measured. The GC-17, GC-4 and IG-5 are new compounds derived from NF115 and showed high antiproliferative activity on tumor cell lines. The GC-17 compound inhibited U373-MG glioblastoma cells (3.2 µM), the effects was fifty times more potent than NF115, and caused a significant reduction of tumor volume (P<0.05) when tested in Wistar rats allotransplanted with C6 glioma cells.


Assuntos
Acetilglucosamina/análogos & derivados , Glioma/tratamento farmacológico , Glicolipídeos/síntese química , Glicoesfingolipídeos/química , Propilenoglicóis/química , Acetilglucosamina/química , Acetilglucosamina/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação da Expressão Gênica , Glicolipídeos/química , Glicolipídeos/farmacologia , Glicoesfingolipídeos/farmacologia , Humanos , Análise em Microsséries , Propilenoglicóis/farmacologia , Inibidor alfa de Dissociação do Nucleotídeo Guanina rho/genética , Inibidor alfa de Dissociação do Nucleotídeo Guanina rho/metabolismo
7.
Mol Cell Neurosci ; 46(1): 89-100, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20801220

RESUMO

The high frequency and malignancy of human glioblastomas has stimulated the search for potential therapeutic approaches. The control of the glioma cell proliferation in response to mitogenic signals is one of the most promising antitumoral strategies, and the main target of several therapies. Neurostatin, an O-acetylated derivative of the ganglioside GD1b, has potent antiproliferative activity over the in vitro and in vivo growth of glioma cells. The mechanism of its antitumoral action is the focus of the present study. Using a combined in vitro-in vivo approach, we observed that neurostatin arrested glioma proliferation by inhibiting the expression of cell cycle promoters (i.e. cyclins and CDKs) and promoting the expression of cell cycle inhibitors (i.e. p21 and p27). Neurostatin inhibits epidermal growth factor receptor (EGFR) signaling pathways, blocking the activation of the main promitogenic MAPKs and PI3K pathways. Neurostatin action not only interferes in the cell cycle progression, but also in the protection from apoptosis, and the generation of angiogenic and invasive responses. The antitumoral actions described here point to neurostatin as a novel and promising chemotherapeutic agent for glioma treatment.


Assuntos
Ciclo Celular/efeitos dos fármacos , Receptores ErbB/metabolismo , Glioma/tratamento farmacológico , Glioma/patologia , Glicoesfingolipídeos/farmacologia , Glicoesfingolipídeos/uso terapêutico , Animais , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/metabolismo , Feminino , Glioma/fisiopatologia , Humanos , Camundongos , Camundongos Nus , Transplante de Neoplasias , Transplante Heterólogo
8.
Glia ; 58(3): 264-76, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19610094

RESUMO

Reactive glia formation is one of the hallmarks of damage to the CNS, but little information exists on the signals that direct its activation. Microglial cells are the main regulators of both innate and adaptative immune responses in the CNS. The proinflammatory cytokine IL-15 is involved in regulating the response of T and B cells, playing a key role in regulating nervous system inflammatory events. We have used a microglial culture model of inflammation induced by LPS and IFNgamma to evaluate the role of IL-15 in the proinflammatory response. Our results indicate that IL-15 is necessary for the reactive response, its deficiency (IL-15-/-) leading to the development of a defective proinflammatory response. Blockade of IL-15, both with blocking antibodies or with the ganglioside Neurostatin, inhibited the activation of the NFkappaB pathway, decreasing iNOS expression and NO production. Inhibiting IL-15 signaling also blocked the activation of the mitogen-activated protein kinase (MAPK) pathways ERK1/2 and p38. The major consequence of these inhibitory effects, analyzed using cytokine antibody arrays, was a severe decrease in the production of chemokines, cytokines and growth factors, like CCL17, CCL19, IL-12, or TIMP-1, that are essential for the development of the phenotypic changes of glial activation. In conclusion, activation of the IL-15 system seems a necessary step for the development of glial reactivity and the regulation of the physiology of glial cells. Modulating IL-15 activity opens the possibility of developing new strategies to control gliotic events upon inflammatory stimulation.


Assuntos
Encefalite/imunologia , Gliose/imunologia , Interleucina-15/metabolismo , Sistema de Sinalização das MAP Quinases/imunologia , NF-kappa B/metabolismo , Animais , Anticorpos Bloqueadores/farmacologia , Linhagem Celular , Células Cultivadas , Quimiocinas/metabolismo , Citocinas/metabolismo , Encefalite/fisiopatologia , Gliose/fisiopatologia , Glicoesfingolipídeos/farmacologia , Mediadores da Inflamação/farmacologia , Interferon gama/farmacologia , Interleucina-15/antagonistas & inibidores , Interleucina-15/genética , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microglia/imunologia , Microglia/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Óxido Nítrico/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
9.
J Neurosci Res ; 88(14): 3034-47, 2010 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-20629188

RESUMO

Every year male deers completely regenerate their antlers. During this process, antlers are reinnervated by sensory fibers, growing at the highest rate recorded for any adult mammal. Despite its clinical potential, only a few studies have dealt with this fascinating phenomenon. Among the possible factors underlying fast growth of the antler's innervation, the effects of the antler's endocrine and paracrine factors were evaluated, using an in vitro assay for sensory neurite growth. We found that soluble molecules secreted by the velvet, the modified skin that covers the antler, strongly promote neurite outgrowth. Using specific blocking antibodies, we demonstrated that nerve growth factor is partially responsible for these effects, although other unidentified molecules are also involved. On the contrary, neither endocrine serum factors nor antler substrates promoted neurite outgrowth, although antler substrata from deep velvet layers cause neurite outgrowth orientation. Taken together, our results point to the existence in the deep velvet of an environment that promotes oriented axon growth, in agreement with the distribution of the antler innervation.


Assuntos
Chifres de Veado/inervação , Chifres de Veado/fisiologia , Cervos/fisiologia , Fatores de Crescimento Neural/metabolismo , Regeneração Nervosa/fisiologia , Neuritos/fisiologia , Células Receptoras Sensoriais/fisiologia , Animais , Células Cultivadas , Meios de Cultivo Condicionados/farmacologia , Masculino , Fatores de Crescimento Neural/antagonistas & inibidores , Fatores de Crescimento Neural/fisiologia , Neuritos/ultraestrutura , Ratos , Células Receptoras Sensoriais/citologia
10.
Glia ; 57(13): 1393-409, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19235256

RESUMO

Cells from central nervous system with morphology similar to radial glia and properties intermediate between astrocytes and Schwann cells were called growth-promoting glia or aldynoglia. These cells are present in adult brain olfactory bulb, hypothalamus, hypophysis, pineal gland and in the developing brain, and spinal cord (Cameron and Rakic (1991) Glia 4:124-137; Gudiño-Cabrera and Nieto-Sampedro (2000) 30:49-63). We report now that neurosphere cells, abundantly generated from E15 rat or E13 mouse corpus striatum, differentiate to aldynoglia-like cells when plated onto an adhesive substrate, and cultured in the presence of olfactory ensheathing cell conditioned medium, supplemented with EGF and bFGF. The immunophenotype, mRNA expression (microarray and RT-PCR analysis), neurite growth-promoting and ensheathing properties of the cells derived from neurospheres were similar to those of aldynoglia. Neurosphere-derived, aldynoglia-like cells expressed, with respect to neurospheres, very increased levels of GFAP, high levels of nestin and vimentin, extracellular matrix proteins, and inhibitors of the catabolism of those extracellular matrix proteins.


Assuntos
Diferenciação Celular/fisiologia , Corpo Estriado/citologia , Neuroglia/fisiologia , Bulbo Olfatório/citologia , Animais , Adesão Celular/genética , Adesão Celular/fisiologia , Movimento Celular , Células Cultivadas , Técnicas de Cocultura , Corpo Estriado/fisiologia , Meios de Cultivo Condicionados , Gânglios Espinais/fisiologia , Proteínas de Fluorescência Verde/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Bainha de Mielina/fisiologia , Neuritos/fisiologia , Neuroglia/citologia , Neurônios/fisiologia , Bulbo Olfatório/fisiologia , Ratos , Ratos Wistar
11.
Nanomaterials (Basel) ; 8(8)2018 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-30044386

RESUMO

The synthesis procedure of nanoparticles based on thermal degradation produces organic solvent dispersible iron oxide nanoparticles (OA-IONP) with oleic acid coating and unique physicochemical properties of the core. Some glycosides with hydrophilic sugar moieties bound to oleyl hydrophobic chains have antimitotic activity on cancer cells but reduced in vivo applications because of the intrinsic low solubility in physiological media, and are prone to enzymatic hydrolysis. In this manuscript, we have synthetized and characterized OA-IONP-based micelles encapsulated within amphiphilic bioactive glycosides. The glycoside-coated IONP micelles were tested as Magnetic Resonance Imaging (MRI) contrast agents as well as antimitotics on rat glioma (C6) and human lung carcinoma (A549) cell lines. Micelle antimitotic activity was compared with the activity of the corresponding free glycosides. In general, all OA-IONP-based micellar formulations of these glycosides maintained their anti-tumor effects, and, in one case, showed an unusual therapeutic improvement. Finally, the micelles presented optimal relaxometric properties for their use as T2-weighed MRI contrast agents. Our results suggest that these bioactive hydrophilic nano-formulations are theranostic agents with synergistic properties obtained from two entities, which separately are not ready for in vivo applications, and strengthen the possibility of using biomolecules as both a coating for OA-IONP micellar stabilization and as drugs for therapy.

12.
BMC Genomics ; 8: 89, 2007 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-17407579

RESUMO

BACKGROUND: Gene expression profiles of non-model mammals may provide valuable data for biomedical and evolutionary studies. However, due to lack of sequence information of other species, DNA microarrays are currently restricted to humans and a few model species. This limitation may be overcome by using arrays developed for a given species to analyse gene expression in a related one, an approach known as "cross-species analysis". In spite of its potential usefulness, the accuracy and reproducibility of the gene expression measures obtained in this way are still open to doubt. The present study examines whether or not hybridization values from cross-species analyses are as reproducible as those from same-species analyses when using Affymetrix oligonucleotide microarrays. RESULTS: The reproducibility of the probe data obtained hybridizing deer, Old-World primates, and human RNA samples to Affymetrix human GeneChip U133 Plus 2.0 was compared. The results show that cross-species hybridization affected neither the distribution of the hybridization reproducibility among different categories, nor the reproducibility values of the individual probes. Our analyses also show that a 0.5% of the probes analysed in the U133 plus 2.0 GeneChip are significantly associated to un-reproducible hybridizations. Such probes-called in the text un-reproducible probe sequences- do not increase in number in cross-species analyses. CONCLUSION: Our study demonstrates that cross-species analyses do not significantly affect hybridization reproducibility of GeneChips, at least within the range of the mammal species analysed here. The differences in reproducibility between same-species and cross-species analyses observed in previous studies were probably caused by the analytical methods used to calculate the gene expression measures. Together with previous observations on the accuracy of GeneChips for cross-species analysis, our analyses demonstrate that cross-species hybridizations may provide useful gene expression data. However, the reproducibility and accuracy of these measures largely depends on the use of appropriated algorithms to derive the gene expression data from the probe data. Also, the identification of probes associated to un-reproducible hybridizations-useless for gene expression analyses- in the studied GeneChip, stress the need of a re-evaluation of the probes' performance.


Assuntos
Cercopithecidae/genética , Cervos/genética , Perfilação da Expressão Gênica , Análise de Sequência com Séries de Oligonucleotídeos , Animais , Sequência de Bases , DNA/análise , Humanos , Masculino , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Sequências Repetitivas de Ácido Nucleico , Reprodutibilidade dos Testes
13.
J Med Chem ; 50(2): 364-73, 2007 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-17228879

RESUMO

An N-acetylglucosaminide derivative with a pentaerythritol substituent at position C-6 was previously synthesized and shown to inhibit neural tumor growth. Now, we report the preparation of a series of new synthetic compounds introducing systematic changes in the nature, polarity, and size of the sugar substituents. The antimitotic activity of the new compounds was tested on cultured rat (C6) and human (U-373) glioma lines and on a human melanoma line (A-375). The antimitotic and antitumoral activity of the new compounds on glioma cell lines increased up to 2 orders of magnitude with respect to the parent compound or was abolished, permitting a detailed structure-function analysis of the new antitumorals. One of the glycosides inhibited melanoma division with an ID50 below the micromolar range.


Assuntos
Antineoplásicos/síntese química , Glioma , Glicosídeos/síntese química , Melanoma , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Glicosídeos/química , Glicosídeos/farmacologia , Humanos , Ratos , Relação Estrutura-Atividade
14.
FASEB J ; 20(3): 491-3, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16407455

RESUMO

Damaged axons do not regenerate after axotomy in the adult mammalian central nervous system (CNS). This may be due to local inhibitory factors at the site of injury, such as overexpression of chondroitin sulfate (CS) proteoglycans (CSPG), and the presence of myelin-associated inhibitors (MAI). To overcome CSPG- or myelin-induced inhibition, strategies based on extrinsic and intrinsic treatments have been developed. For example, NEP1-40 is a synthetic peptide that promotes axonal regeneration by blocking Nogo-66/NgR interaction and chondroitinase ABC (ChABC), which degrades CS, thereby also promoting axon regrowth. Here, we examined whether the combination of these complementary strategies facilitates regeneration of the lesioned entorhino-hippocampal pathway (EHP) in slice cultures. In this model, overexpressed CSPG and MAI impaired axon regrowth, which mimics regeneration failure in vivo. Both CS cleavage with ChABC and NEP1-40 strongly facilitated the regrowth of entorhinal axons after axotomy, permitting the re-establishment of synaptic contacts with target cells. However, the combined treatment did not improve the regeneration induced by ChABC alone, and the delayed treatment of ChABC, but not NEP1-40, had a less pronounced effect on axonal regrowth compared with acute treatment. These results provide insight into the development of new assays and strategies to enhance axon regeneration in injured cortical connections.


Assuntos
Proteoglicanas de Sulfatos de Condroitina/antagonistas & inibidores , Córtex Entorrinal/fisiologia , Hipocampo/fisiologia , Proteínas da Mielina/antagonistas & inibidores , Regeneração Nervosa/fisiologia , Receptores de Superfície Celular/antagonistas & inibidores , Animais , Axotomia , Condroitina ABC Liase/farmacologia , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Córtex Entorrinal/lesões , Proteínas Ligadas por GPI , Hipocampo/lesões , Técnicas In Vitro , Camundongos , Proteínas da Mielina/biossíntese , Proteínas da Mielina/farmacologia , Proteínas da Mielina/fisiologia , Neuroglia/fisiologia , Proteínas Nogo , Receptor Nogo 1 , Fragmentos de Peptídeos/farmacologia , Receptores de Superfície Celular/biossíntese , Receptores de Superfície Celular/fisiologia , Transdução de Sinais/efeitos dos fármacos
15.
Biomed Res Int ; 2017: 6953156, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28536699

RESUMO

Central nervous system (CNS) injuries, caused by cerebrovascular pathologies or mechanical contusions (e.g., traumatic brain injury, TBI) comprise a diverse group of disorders that share the activation of the integrated stress response (ISR). This pathway is an innate protective mechanism, with encouraging potential as therapeutic target for CNS injury repair. In this review, we will focus on the progress in understanding the role of the ISR and we will discuss the effects of various small molecules that target the ISR on different animal models of CNS injury.


Assuntos
Lesões Encefálicas Traumáticas/fisiopatologia , Sistema Nervoso Central/fisiopatologia , Traumatismos da Medula Espinal/fisiopatologia , Animais , Sistema Nervoso Central/lesões , Humanos , Modelos Animais , Estresse Fisiológico
16.
Mol Neurobiol ; 54(9): 6737-6749, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-27744574

RESUMO

The bile acid conjugate tauroursodeoxycholic acid (TUDCA) is a neuroprotective agent in various animal models of neuropathologies. We have previously shown the anti-inflammatory properties of TUDCA in an animal model of acute neuroinflammation. Here, we present a new anti-inflammatory mechanism of TUDCA through the regulation of transforming growth factor ß (TGFß) pathway. The bacterial lipopolysaccharide (LPS) was injected intravenously (iv) on TGFß reporter mice (Smad-binding element (SBE)/Tk-Luc) to study in their brains the real-time activation profile of the TGFß pathway in a non-invasive way. The activation of the TGFß pathway in the brain of SBE/Tk-Luc mice increased 24 h after LPS injection, compared to control animals. This activation peak increased further in mice treated with both LPS and TUDCA than in mice treated with LPS only. The enhanced TGFß activation in mice treated with LPS and TUDCA correlated with both an increase in TGFß3 transcript in mouse brain and an increase in TGFß3 immunoreactivity in microglia/macrophages, endothelial cells, and neurons. Inhibition of the TGFß receptor with SB431542 drug reverted the effect of TUDCA on microglia/macrophages activation and on TGFß3 immunoreactivity. Under inflammatory conditions, treatment with TUDCA enhanced further the activation of TGFß pathway in mouse brain and increased the expression of TGFß3. Therefore, the induction of TGFß3 by TUDCA might act as a positive feedback, increasing the initial activation of the TGFß pathway by the inflammatory stimulus. Our findings provide proof-of-concept that TGFß contributes to the anti-inflammatory effect of TUDCA under neuroinflammatory conditions.


Assuntos
Anti-Inflamatórios/administração & dosagem , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Modelos Animais de Doenças , Ácido Tauroquenodesoxicólico/administração & dosagem , Fator de Crescimento Transformador beta/biossíntese , Animais , Encéfalo/diagnóstico por imagem , Inflamação/diagnóstico por imagem , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Medições Luminescentes/métodos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
17.
J Neurotrauma ; 23(1): 1-17, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16430369

RESUMO

The rat is widely used for modeling human spinal cord injury (SCI) and paraplegia. However, quadruped animals adapt trunk, forelimb and hindlimb movements to compensate for deficits, improving their behavioral scores and complicating the interpretation of spontaneous and treatment-induced function recovery. The kinematics of locomotion was studied in rats, both normal and after SCI (T9 contusion), and variables indicative of hindlimb function were related to brain-spinal cord connections (BSCC) spared during lesioning. Normal animals showed forward velocities characteristic of fast walking. The hind paw was placed approximately three centimeters in front of the hip at the initial contact. Hip height decreased during the first third of hindlimb stance and increased later. Mild and moderate spinal cord contusions destroyed the gray matter and adjacent axons but spared the ventrolateral tracts to various degrees. Injured animals placed the hindpaw in a more caudal position than normal and showed reduced forward velocity and hip height. Knee extension was also impaired, and both hindlimb and forelimb steps were adapted to compensate for the deficits. BSCC was estimated by averaging the transverse area of white matter at the lesion epicenter and the percentage of brain neurons labeled after peroxidase injection into L2 and L3. Recovery of hindlimb motor function was proportional to the amount of BSCC. On average, injured animals retained 18% of BSSC and recovered 23% of hindlimb function. These findings show that kinematic analysis is a reliable tool for assessing locomotor deficits and compensations and suggest limited spontaneous motor plasticity after SCI.


Assuntos
Adaptação Fisiológica/fisiologia , Transtornos Neurológicos da Marcha/fisiopatologia , Plasticidade Neuronal/fisiologia , Recuperação de Função Fisiológica/fisiologia , Traumatismos da Medula Espinal/fisiopatologia , Animais , Transporte Axonal , Fenômenos Biomecânicos , Denervação , Avaliação da Deficiência , Modelos Animais de Doenças , Vias Eferentes/lesões , Vias Eferentes/patologia , Vias Eferentes/fisiopatologia , Membro Anterior/inervação , Membro Anterior/fisiopatologia , Transtornos Neurológicos da Marcha/diagnóstico , Membro Posterior/inervação , Membro Posterior/fisiopatologia , Peroxidase do Rábano Silvestre , Masculino , Contração Muscular/fisiologia , Músculo Esquelético/inervação , Músculo Esquelético/fisiopatologia , Neurônios/citologia , Neurônios/fisiologia , Ratos , Ratos Wistar , Medula Espinal/patologia , Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/diagnóstico , Vértebras Torácicas
18.
Neural Regen Res ; 11(7): 1043-5, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27630672

RESUMO

A combined approach in spinal cord injury (SCI) therapy is the modulation of the cellular and molecular processes involved in glial scarring. Aldaynoglial cells are neural cell precursors with a high capacity to differentiate into neurons, promote axonal growth, wrapping and myelination of resident neurons. These important characteristics of aldaynoglia can be combined with specific inhibition of the RhoGTPase activity in astroglia and microglia that cause reduction of glial proliferation, retraction of glial cell processes and myelin production by oligodendrocytes. Previously we used experimental central nervous system (CNS) injury models, like spinal cord contusion and striatal lacunar infarction and observed that administration of RhoGTPase glycolipid inhibitor or aldaynoglial cells, respectively, produced a significant gain of functional recovery in treated animals. The combined therapy with neuro-regenerative properties strategy is highly desirable to treat SCI for functional potentiation of neurons and oligodendrocytes, resulting in better locomotor recovery. Here we suggest that treatment of spinal lesions with aldaynoglia from neurospheres plus local administration of a RhoGTPase inhibitor could have an additive effect and promote recovery from SCI.

19.
J Neurotrauma ; 22(5): 544-58, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15892600

RESUMO

Information on the nature of deficits and adaptive mechanisms occurring after spinal cord injury is essential to the design of strategies for promoting functional recovery. Motor impairments and compensations were quantified by three-dimensional kinematic analysis in freely walking rats, 6 months after mild cervical (C7) or moderate lumbar (L2) spinal cord contusion. After C7 contusion, the animals showed reduced elbow extension and wrist movement, whereas reduced knee extension was the main impairment after L2 contusion. In both cases, the duration of the walking cycle increased and forward velocity was reduced due to a longer stance phase. Histology revealed reproducible lesions extending approximately to one spinal cord segment. In the transverse plane, the lesion involved the central gray matter and adjacent axons, including the dorsal corticospinal tract, but partially spared the ventrolateral tracts. Retrograde motoneuron tracing by nerve exposure to HRP or intramuscular injection of aminostilbamidine demonstrated that C7 contusion caused the loss of approximately 40% of triceps brachii motoneurons, whereas approximately 30% of quadriceps femoris motoneurons were lost after L2 contusion. These results demonstrate permanent deficits after incomplete lesions at the spinal cord enlargements and suggest that motoneuron loss contributes to their production.


Assuntos
Transtornos Neurológicos da Marcha/patologia , Neurônios Motores/patologia , Transtornos dos Movimentos/patologia , Paralisia/patologia , Traumatismos da Medula Espinal/patologia , Medula Espinal/patologia , Animais , Fenômenos Biomecânicos , Morte Celular/fisiologia , Vértebras Cervicais , Doença Crônica , Modelos Animais de Doenças , Membro Anterior/inervação , Membro Anterior/fisiopatologia , Transtornos Neurológicos da Marcha/etiologia , Transtornos Neurológicos da Marcha/fisiopatologia , Membro Posterior/inervação , Membro Posterior/fisiopatologia , Vértebras Lombares , Masculino , Transtornos dos Movimentos/etiologia , Transtornos dos Movimentos/fisiopatologia , Músculo Esquelético/inervação , Músculo Esquelético/fisiopatologia , Degeneração Neural/patologia , Degeneração Neural/fisiopatologia , Vias Neurais/lesões , Vias Neurais/patologia , Vias Neurais/fisiopatologia , Paralisia/etiologia , Paralisia/fisiopatologia , Ratos , Ratos Wistar , Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/fisiopatologia , Fatores de Tempo
20.
J Neurosurg Spine ; 3(4): 308-17, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16266073

RESUMO

OBJECT: The results of olfactory ensheathing cell (OEC) transplantation have raised great expectations as a potential treatment for spinal cord injury (SCI). Its capacity to promote functional neural repair, however, remains unclear. The authors studied axonal growth and locomotor recovery after C-7 contusion injury and OEC transplantation in adult rats. METHODS: Twenty-four male Wistar rats underwent a mild C-7 contusion injury that completely disrupted the dorsal corticospinal tract (DCST). In 14 rats OECs were transplanted into the lesion, and 10 were used as controls. At 3 months postcontusion, the kinematics of locomotion were assessed, and the CST was traced by injecting dextran tetramethylrhodamine bilaterally into the cerebral cortex. The animals were killed 2 weeks after tracer injection, and their spinal cords were studied immunohistochemically. Although the survival of transplanted cells varied, they were present in all cases. The authors observed neither OEC migration nor DCST axon regeneration in any of the cell transplant-treated rats. Corticospinal axons ended in retraction bulbs at the proximal edge of the lesion or, exceptionally, a few micrometers inside the transplant. The results of neurofilament immunohistochemical analysis provided evidence of neurites from systems other than the DCST growing into the transplant, but in some cases these neurites formed loops of pathological appearance. Contusion injury of C-7 caused chronic locomotor deficits that did not improve after OEC transplants. CONCLUSIONS: The findings in this study indicate that OEC transplants alone are not sufficient for neural repair and functional recovery after SCI. In addition, OECs can induce abnormal axonal growth, making further studies necessary before considering their clinical use.


Assuntos
Regeneração Nervosa/fisiologia , Neuroglia/transplante , Traumatismos da Medula Espinal/terapia , Animais , Axônios , Fenômenos Biomecânicos , Movimento Celular , Sobrevivência Celular , Vértebras Cervicais , Locomoção , Ratos , Ratos Wistar , Traumatismos da Medula Espinal/veterinária , Resultado do Tratamento
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