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1.
Chemosphere ; 245: 125679, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31869672

RESUMO

17ß-Trenbolone (17ß-TBOH) is an endocrine disruptor that has been widely reported in aquatic organisms. However, little is known about the effect of 17ß-TBOH on mammals, particularly on the development of adolescents. Through a series of behavioural experiments, exposure to at 80 µg kg -1 d -1 and 800 µg kg -1 d -1 17ß-TBOH during puberty (from PND 28 to 56, male mice) increased anxiety-like behaviours. Exposure to the low dose of 80 µg kg -1 d -1 resulted in a clear social avoidance behaviour in mice. The two doses affected testicular development and endogenous androgen synthesis in male mice. In addition, 17ß-TBOH exposure altered the differentiation of oligodendrocytes and the formation of the myelin sheath in the medial prefrontal cortex (mPFC). These results reveal the effects of 17ß-TBOH on the behaviours, gonadal and neurodevelopment of adolescent mammals. In addition, the inhibition of the secretion of endogenous hormones and decrease in the formation of the myelin sheath in mPFC may be associated with the 17ß-TBOH-induced behavioural changes in mice.


Assuntos
Hormônios Esteroides Gonadais/biossíntese , Comportamento Social , Acetato de Trembolona/farmacologia , Animais , Ansiedade/induzido quimicamente , Aprendizagem da Esquiva/efeitos dos fármacos , Disruptores Endócrinos/farmacologia , Masculino , Camundongos , Bainha de Mielina/efeitos dos fármacos , Oligodendroglia/efeitos dos fármacos
2.
Mar Drugs ; 17(10)2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31590222

RESUMO

Currently, animal experiments in rodents are the gold standard for developmental neurotoxicity (DNT) investigations; however, testing guidelines for these experiments are insufficient in terms of animal use, time, and costs. Thus, alternative reliable approaches are needed for predicting DNT. We chose rat neural stem cells (rNSC) as a model system, and used a well-known neurotoxin, domoic acid (DA), as a model test chemical to validate the assay. This assay was used to investigate the potential neurotoxic effects of Ochratoxin A (OTA), of which the main target organ is the kidney. However, limited information is available regarding its neurotoxic effects. The effects of DA and OTA on the cytotoxicity and on the degree of differentiation of rat rNSC into astrocytes, neurons, and oligodendrocytes were monitored using cell-specific immunofluorescence staining for undifferentiated rNSC (nestin), neurospheres (nestin and A2B5), neurons (MAP2 clone M13, MAP2 clone AP18, and Doublecortin), astrocytes (GFAP), and oligodendrocytes (A2B5 and mGalc). In the absence of any chemical exposure, approximately 46% of rNSC differentiated into astrocytes and neurons, while 40.0% of the rNSC differentiated into oligodendrocytes. Both non-cytotoxic and cytotoxic concentrations of DA and OTA reduced the differentiation of rNSC into astrocytes, neurons, and oligodendrocytes. Furthermore, a non-cytotoxic nanomolar (0.05 µM) concentration of DA and 0.2 µM of OTA reduced the percentage differentiation of rNSC into astrocytes and neurons. Morphometric analysis showed that the highest concentrations (10 µM) of DA reduced axonal length. These indicate that low, non-cytotoxic concentrations of DA and OTA can interfere with the differentiation of rNSC.


Assuntos
Ácido Caínico/análogos & derivados , Células-Tronco Neurais/efeitos dos fármacos , Síndromes Neurotóxicas/etiologia , Neurotoxinas/efeitos adversos , Ocratoxinas/efeitos adversos , Animais , Astrócitos/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Ácido Caínico/efeitos adversos , Neurônios/efeitos dos fármacos , Oligodendroglia/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
3.
Int J Mol Sci ; 20(18)2019 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-31540019

RESUMO

Evidence has been accumulated demonstrating that heavy metals may accumulate in various organs, leading to tissue damage and toxic effects in mammals. In particular, the Central Nervous System (CNS) seems to be particularly vulnerable to cumulative concentrations of heavy metals, though the pathophysiological mechanisms is still to be clarified. In particular, the potential role of oligodendrocyte dysfunction and myelin production after exposure to subtoxic concentration I confirmed. It is ok of heavy metals is to be better assessed. Here we investigated on the effect of sub-toxic concentration of several essential (Cu2 +, Cr3 +, Ni2 +, Co2+) and non-essential (Pb2 +, Cd2+, Al3+) heavy metals on human oligodendrocyte MO3.13 and human neuronal SHSY5Y cell lines (grown individually or in co-culture). MO3.13 cells are an immortal human-human hybrid cell line with the phenotypic characteristics of primary oligodendrocytes but following the differentiation assume the morphological and biochemical features of mature oligodendrocytes. For this reason, we decided to use differentiated MO3.13 cell line. In particular, exposure of both cell lines to heavy metals produced a reduced cell viability of co-cultured cell lines compared to cells grown separately. This effect was more pronounced in neurons that were more sensitive to metals than oligodendrocytes when the cells were grown in co-culture. On the other hand, a significant reduction of lipid component in cells occurred after their exposure to heavy metals, an effect accompanied by substantial reduction of the main protein that makes up myelin (MBP) in co-cultured cells. Finally, the effect of heavy metals in oligodendrocytes were associated to imbalanced intracellular calcium ion concentration as measured through the fluorescent Rhod-2 probe, thus confirming that heavy metals, even used at subtoxic concentrations, lead to dysfunctional oligodendrocytes. In conclusion, our data show, for the first time, that sub-toxic concentrations of several heavy metals lead to dysfunctional oligodendrocytes, an effect highlighted when these cells are co-cultured with neurons. The pathophysiological mechanism(s) underlying this effect is to be better clarified. However, imbalanced intracellular calcium ion regulation, altered lipid formation and, finally, imbalanced myelin formation seem to play a major role in early stages of heavy metal-related oligodendrocyte dysfunction.


Assuntos
Metais Pesados/toxicidade , Proteína Básica da Mielina/metabolismo , Neurônios/metabolismo , Oligodendroglia/metabolismo , Cálcio/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular , Sistema Nervoso Central , Humanos , Metais Pesados/química , Bainha de Mielina/metabolismo , Neurogênese/efeitos dos fármacos , Neurônios/química , Neurônios/efeitos dos fármacos , Neurônios/patologia , Oligodendroglia/química , Oligodendroglia/efeitos dos fármacos , Oligodendroglia/patologia
4.
J Neuroinflammation ; 16(1): 165, 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31399117

RESUMO

BACKGROUND: The association of gut microbiota and diseases of the central nervous system (CNS), including multiple sclerosis (MS), has attracted much attention. Although a previous analysis of MS gut microbiota revealed a reduction in species producing short-chain fatty acids (SCFAs), the influence of these metabolites on demyelination and remyelination, the critical factors of MS pathogenesis, remains unclear. METHODS: To investigate the relationship between demyelination and gut microbiota, we administered a mixture of non-absorbing antibiotics or SCFAs to mice with cuprizone-induced demyelination and evaluated demyelination and the accumulation of microglia. To analyze the direct effect of SCFAs on demyelination or remyelination, we induced demyelination in an organotypic cerebellar slice culture using lysolecithin and analyzed the demyelination and maturation of oligodendrocyte precursor cells with or without SCFA treatment. RESULTS: The oral administration of antibiotics significantly enhanced cuprizone-induced demyelination. The oral administration of butyrate significantly ameliorated demyelination, even though the accumulation of microglia into demyelinated lesions was not affected. Furthermore, we showed that butyrate treatment significantly suppressed lysolecithin-induced demyelination and enhanced remyelination in an organotypic slice culture in the presence or absence of microglia, suggesting that butyrate may affect oligodendrocytes directly. Butyrate treatment facilitated the differentiation of immature oligodendrocytes. CONCLUSIONS: We revealed that treatment with butyrate suppressed demyelination and enhanced remyelination in an organotypic slice culture in association with facilitating oligodendrocyte differentiation. Our findings shed light on a novel mechanism of interaction between the metabolites of gut microbiota and the CNS and may provide a strategy to control demyelination and remyelination in MS.


Assuntos
Butiratos/uso terapêutico , Doenças Desmielinizantes/metabolismo , Doenças Desmielinizantes/prevenção & controle , Bainha de Mielina/efeitos dos fármacos , Bainha de Mielina/metabolismo , Remielinização/efeitos dos fármacos , Animais , Antibacterianos/toxicidade , Butiratos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Cuprizona/toxicidade , Doenças Desmielinizantes/induzido quimicamente , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Oligodendroglia/efeitos dos fármacos , Oligodendroglia/metabolismo , Técnicas de Cultura de Órgãos , Remielinização/fisiologia
5.
Mol Biol Rep ; 46(5): 4817-4826, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31270757

RESUMO

Oligodendrocyte precursor cells (OPC) are a uniformly distributed population of glial cells that are well known for proliferating and differentiating into mature oligodendrocytes to form the myelin sheet in the central nervous system (CNS). Since monocarboxylate transporter 1 (MCT1) has shown to be expressed by oligodendroglia, the involvement of these cells with the metabolic support to axons has emerged as an important role in the maintenance of neuronal functionality. Hyperglycemia is a metabolic dysfunction highly associated with oxidative stress, a classical feature linked to many disorders such as diabetes mellitus. Despite of being widely investigated in several different cell cultures, including astrocytes and neurons, such condition has been poorly investigated in OPC culture. Thus, the aim of this study was to explore the possible effects of high-glucose exposure in acute and chronic conditions on oligodendroglial development and functionality in vitro. In this sense, we have demonstrated that under high-glucose exposure OPC improved its differentiation rate without affecting its membrane integrity and its morphology. Besides, chronic high-glucose condition also increased glucose uptake and lactate release. On the other hand, our findings also showed that, unlike what happens in other glial cells and neurons, high-glucose exposure did not seem to induce oxidative stress in OPC culture. Therefore, as far as we have investigated in this present study, we suggest that OPC may be able to support neurons and other glial cells during hyperglycemia events.


Assuntos
Diferenciação Celular , Metabolismo Energético , Glucose/metabolismo , Oligodendroglia/citologia , Oligodendroglia/metabolismo , Animais , Biomarcadores , Glicemia , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Glucose/farmacologia , Hiperglicemia/metabolismo , Imunofenotipagem , Ácido Láctico/biossíntese , Oligodendroglia/efeitos dos fármacos , Oxirredução , Ratos
6.
J Steroid Biochem Mol Biol ; 194: 105432, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31344443

RESUMO

Oxidative stress and mitochondrial dysfunction contribute to the pathogenesis of neurodegenerative diseases and favor lipid peroxidation, leading to increased levels of 7ß-hydroxycholesterol (7ß-OHC) which induces oxiapoptophagy (OXIdative stress, APOPTOsis, autoPHAGY). The cytoprotective effects of dimethylfumarate (DMF), used in the treatment of relapsing remitting multiple sclerosis and of monomethylfumarate (MMF), its main metabolite, were evaluated on murine oligodendrocytes 158 N exposed to 7ß-OHC (50 µM, 24 h) with or without DMF or MMF (25 µM). The activity of 7ß-OHC in the presence or absence DMF or MMF was evaluated on several parameters: cell adhesion; plasma membrane integrity measured with propidium iodide (PI), trypan blue and fluoresceine diacetate (FDA) assays; LDH activity; antioxidant enzyme activities (superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx)); generation of lipid peroxidation products (malondialdehyde (MDA), conjugated dienes (CDs)) and protein oxidation products (carbonylated proteins (CPs)); reactive oxygen species (ROS) overproduction conducted with DHE and DHR123. The effect on mitochondria was determined with complementary criteria: measurement of succinate dehydrogenase activity, evaluation of mitochondrial potential (ΔΨm) and mitochondrial superoxide anions (O2●-) production using DiOC6(3) and MitoSOX, respectively; quantification of mitochondrial mass with Mitotracker Red, and of cardiolipins and organic acids. The effects on mitochondrial and peroxisomal ultrastructure were determined by transmission electron microscopy. Intracellular sterol and fatty acid profiles were determined. Apoptosis and autophagy were characterized by staining with Hoechst 33,342, Giemsa and acridine orange, and with antibodies raised against caspase-3 and LC3. DMF and MMF attenuate 7ß-OHC-induced cytotoxicity: cell growth inhibition; decreased cell viability; mitochondrial dysfunction (decrease of succinate dehydrogenase activity, loss of ΔΨm, increase of mitochondrial O2●- production, alteration of the tricarboxilic acid (TCA) cycle, and cardiolipins content); oxidative stress induction (ROS overproduction, alteration of GPx, CAT, and SOD activities, increased levels of MDA, CDs, and CPs); changes in fatty acid and cholesterol metabolism; and cell death induction (caspase-3 cleavage, activation of LC3-I in LC3-II). Ultrastructural alterations of mitochondria and peroxisomes were prevented. These results demonstrate that DMF and MMF prevent major dysfunctions associated with neurodegenerative diseases: oxidative stress, mitochondrial dysfunction, apoptosis and autophagy.


Assuntos
Fumarato de Dimetilo/farmacologia , Fumaratos/farmacologia , Maleatos/farmacologia , Mitocôndrias/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Linhagem Celular , Colesterol/metabolismo , Hidroxicolesteróis/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Camundongos , Mitocôndrias/metabolismo , Mitocôndrias/fisiologia , Mitocôndrias/ultraestrutura , Oligodendroglia/efeitos dos fármacos , Oligodendroglia/metabolismo , Estresse Oxidativo/efeitos dos fármacos
7.
Life Sci ; 232: 116501, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31163175

RESUMO

AIMS: Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system (CNS). The disease mechanisms driving progressive MS remain unresolved. Without this information, current therapeutic strategies are unsatisfactory in preventing disease progression. Our previous work revealed that DL-3-n-butylphthalide (NBP) treatment reduced demyelination in an ethidium bromide mouse model of demyelination. Here, we examine the effect of NBP in the cuprizone model of demyelination by evaluating the pathologic, functional, and behavioral consequences of treatment with NBP. MATERIALS AND METHODS: Forty mice were divided randomly into 4 groups: a normal diet group, a cuprizone diet group, and two NBP groups (10 and 20 mg/kg). CNS infiltration by microglia, axon health and myelination were assessed using immunohistochemistry and electron microscopy, and the levels of cytoplasmic complexes were assessed by Western blotting. KEY FINDINGS: The results showed the neuroprotective effects of the NBP included suppressing the microglia activation through inhibition of nuclear factor-κB (NF-κB) expression, thus decreasing activation of the NF-κB signaling pathway. In particular, myelin density was increased due to an increased mean number of mature oligodendrocytes (OLs) in the high-dose NBP (20 mg/kg) subgroup through reduced oligodendrocyte apoptosis. Meanwhile, increased expression of myelin sheath proteins, including proteolipid protein (PLP) and myelin basic protein (MBP), was observed in the same subgroup. SIGNIFICANCE: These data suggest that NBP may not only have anti-inflammatory properties but also promote the survival of OLs in a mouse cuprizone model of demyelination. NBP may have a potential role in the treatment of MS.


Assuntos
Benzofuranos/farmacologia , Doenças Desmielinizantes/tratamento farmacológico , Esclerose Múltipla/metabolismo , Animais , Astrócitos/metabolismo , Axônios/patologia , Corpo Caloso/efeitos dos fármacos , Corpo Caloso/fisiologia , Cuprizona/farmacologia , Doenças Desmielinizantes/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/fisiopatologia , Bainha de Mielina/metabolismo , NF-kappa B/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Oligodendroglia/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
8.
Biomed Environ Sci ; 32(4): 291-299, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31217065

RESUMO

OBJECTIVE: Age-related diseases, including neurodegenerative diseases, are associated with oxidative stress and lipid peroxidation, and increase the levels of cholesterol auto-oxidation products such as 7ß-hydroxycholesterol (7ß-OHC). Thus, it is imperative to identify agents that can prevent 7ß-OHC-induced side-effects. METHODS: We evaluated the potential protective effects of Carpobrotus edulis ethanol-water extract (EWe) on murine oligodendrocytes (158N) cultured in the absence or presence of 7ß-OHC (20 µg/mL, 24 h). The cells were incubated with EWe (20-200 µg/mL) 2 h before 7ß-OHC treatment. Mitochondrial activity and cell growth were evaluated with the MTT assay. Photometric methods were used to analyze antioxidant enzyme [catalase (CAT) and glutathione peroxidase (GPx)] activities and the generation of lipid and protein oxidation products [malondialdehyde (MDA), conjugated diene (CD), and carbonylated proteins (CPs)]. RESULTS: Treatment with 7ß-OHC induced cell death and oxidative stress (reflected by alteration in CAT and SOD activities). Overproduction of lipid peroxidation products (MDA and CDs) and CPs was also reported. The cytotoxic effects associated with 7ß-OHC were attenuated by 160 µg/mL of EWe of C. edulis. Cell death induced by 7ß-OHC treatment was ameliorated, GPx and CAT activities were restored to normal, and MDA, CD, and CP levels were reduced following C. edulis extract treatment. CONCLUSION: These data demonstrate the protective activities of C. edulis EWe against 7ß-OHC-induced disequilibrium in the redox status of 158N cells, indicative of the potential role of this plant extract in the prevention of neurodegenerative diseases.


Assuntos
Aizoaceae , Doenças Neurodegenerativas/prevenção & controle , Oligodendroglia/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Linhagem Celular , Avaliação Pré-Clínica de Medicamentos , Hidroxicolesteróis , Camundongos , Neuroproteção , Oligodendroglia/metabolismo , Fitoterapia , Extratos Vegetais/uso terapêutico
9.
Free Radic Res ; 53(5): 535-561, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31039616

RESUMO

Mitochondrial dysfunction and oxidative stress are involved in neurodegenerative diseases associated with an enhancement of lipid peroxidation products such as 7ß-hydroxycholesterol (7ß-OHC). It is, therefore, important to study the ability of 7ß-OHC to trigger mitochondrial defects, oxidative stress, metabolic dysfunctions and cell death, which are hallmarks of neurodegeneration, and to identify cytoprotective molecules. The effects of biotin were evaluated on 158N murine oligodendrocytes, which are myelin synthesizing cells, exposed to 7ß-OHC (50 µM) with or without biotin (10 and 100 nM) or α-tocopherol (positive control of cytoprotection). The effects of biotin on 7ß-OHC activities were determined using different criteria: cell adhesion; plasma membrane integrity; redox status. The impact on mitochondria was characterized by the measurement of transmembrane mitochondrial potential (ΔΨm), reactive oxygen species (ROS) overproduction, mitochondrial mass, quantification of cardiolipins and organic acids. Sterols and fatty acids were also quantified. Cell death (apoptosis, autophagy) was characterized by the enumeration of apoptotic cells, caspase-3 activation, identification of autophagic vesicles, and activation of LC3-I into LC3-II. Biotin attenuates 7ß-OHC-induced cytotoxicity: loss of cell adhesion was reduced; antioxidant activities were normalized. ROS overproduction, protein and lipid oxidation products were decreased. Biotin partially restores mitochondrial functions: attenuation of the loss of ΔΨm; reduced levels of mitochondrial O2•- overproduction; normalization of cardiolipins and organic acid levels. Biotin also normalizes cholesterol and fatty acid synthesis, and prevents apoptosis and autophagy (oxiapoptophagy). Our data support that biotin, which prevents oligodendrocytes damages, could be useful in the treatment of neurodegeneration and demyelination.


Assuntos
Antioxidantes/farmacologia , Biotina/farmacologia , Hidroxicolesteróis/antagonistas & inibidores , Metabolismo dos Lipídeos/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , alfa-Tocoferol/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Autofagia/efeitos dos fármacos , Caspase 3/genética , Caspase 3/metabolismo , Catalase/genética , Catalase/metabolismo , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Ácidos Graxos/biossíntese , Regulação da Expressão Gênica , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Hidroxicolesteróis/farmacologia , Metabolismo dos Lipídeos/genética , Peroxidação de Lipídeos/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Mitocôndrias/metabolismo , Oligodendroglia/citologia , Oligodendroglia/efeitos dos fármacos , Oligodendroglia/metabolismo , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
10.
Cell Biol Int ; 43(7): 809-819, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31050073

RESUMO

Our research group has developed a cell-penetrating peptide-based delivery system that includes the Asn194Lys mutation in the rabies virus glycoprotein-9R peptide (mRVG-9R). This system has the capacity to deliver DNA in astrocytes and SH-SY5Y cells. The aim of this study was to evaluate the ability of the mRVG-9R peptide to deliver DNA molecules to murine brain cells. The mRVG-9R peptide, a karyophilic peptide (KP) and a plasmid encoding green fluorescent protein (GFP) were bound by electrostatic charges to form the mRVG-9R complex. mRVG-9R complex was injected into the cerebral cortex, striatum and hippocampus of C57BL/6 mice by stereotactic surgery. After 2, 4, and 20 days, the animals were sacrificed and their brains were prepared for quantitative reverse-transcription polymerase chain reaction and histological analysis. We detected the GFP expression in neurons and glial cells in the cerebral cortex, striatum, and hippocampus of the murine brain. The results suggest that the mRVG-9R peptide has the ability to deliver DNA molecules to murine brain cells. Also, the expression of the reporter gene is maintained at least up to 20 days after injection in neurons, astrocytes, oligodendrocytes, and microglia cells. Thus, the in vivo transfection ability of the mRVG-9R peptide, makes it a promising candidate as a therapeutic gene delivery vector to the central nervous system cells.


Assuntos
Peptídeos Penetradores de Células/farmacologia , Corpo Estriado/efeitos dos fármacos , Portadores de Fármacos/farmacologia , Glicoproteínas/farmacologia , Proteínas de Fluorescência Verde/metabolismo , Hipocampo/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Proteínas Virais/farmacologia , Animais , Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Corpo Estriado/citologia , Genes Reporter , Vetores Genéticos/uso terapêutico , Proteínas de Fluorescência Verde/genética , Hipocampo/citologia , Camundongos , Camundongos Endogâmicos C57BL , Microglia/citologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Oligodendroglia/citologia , Oligodendroglia/efeitos dos fármacos , Transfecção/métodos
11.
Elife ; 82019 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-31071011

RESUMO

Oligodendrocyte maturation is necessary for functional regeneration in the CNS; however, the mechanisms by which the systemic environment regulates oligodendrocyte maturation is unclear. We found that Transforming growth factor (TGF)-ß1, which is present in higher levels in the systemic environment, promotes oligodendrocyte maturation. Oligodendrocyte maturation was enhanced by adult mouse serum treatment via TGF-ß type I receptor. Decrease in circulating TGF-ß1 level prevented remyelination in the spinal cord after toxin-induced demyelination. TGF-ß1 administration promoted remyelination and restored neurological function in a multiple sclerosis animal model. Furthermore, TGF-ß1 treatment stimulated human oligodendrocyte maturation. These data provide the therapeutic possibility of TGF-ß for demyelinating diseases.


Assuntos
Sistema Nervoso Central/efeitos dos fármacos , Doenças Desmielinizantes/tratamento farmacológico , Esclerose Múltipla/tratamento farmacológico , Oligodendroglia/efeitos dos fármacos , Remielinização/efeitos dos fármacos , Fator de Crescimento Transformador beta1/administração & dosagem , Adulto , Animais , Células Cultivadas , Doenças Desmielinizantes/induzido quimicamente , Modelos Animais de Doenças , Humanos , Camundongos , Fator de Crescimento Transformador beta1/sangue , Resultado do Tratamento
12.
Cell Biol Int ; 43(6): 706-714, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30977573

RESUMO

Early exposure to lead (Pb) has been associated with an elevated risk of developing neurodegenerative diseases. There is evidence that neuronal damage in chronic Pb exposure can be caused by the convergence of glial damage. Apoptosis may be a possible mechanism of Pb-induced cell death in the central nervous system. We tested cellular damage and apoptosis in the spinal cord of Wistar rats treated with Pb. Twelve rats were divided into two groups (n = 6): the control group was treated with only drinking water and the other group received 500 ppm of Pb acetate. After 3 months of Pb treatment, all animals were euthanized and spinal cords were extracted. Morphology was evaluated by Nissl and Kluver-Barrera stainings. Apoptosis was detected by terminal deoxynucleotidyl transferase dUTP nick end labeling assay. Specific antibodies were used to evaluate Pb damage in oligodendrocytes, astrocytes, and microglia. A large number of apoptotic bodies was observed in the white matter of the Pb-treated group. The Pb-treated group also showed a reduced number of neurons and oligodendrocytes but had an increased number of astrocytes compared with the nontreated group. Our results demonstrate that chronic Pb treatment induces neurodegeneration, demyelination, and astrogliosis in the rat spinal cord.


Assuntos
Intoxicação por Chumbo/metabolismo , Chumbo/efeitos adversos , Medula Espinal/efeitos dos fármacos , Animais , Apoptose/fisiologia , Astrocitoma/metabolismo , Astrocitoma/fisiopatologia , Morte Celular/fisiologia , Doenças Desmielinizantes/metabolismo , Doenças Desmielinizantes/fisiopatologia , Masculino , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Oligodendroglia/efeitos dos fármacos , Ratos , Ratos Wistar , Medula Espinal/metabolismo , Medula Espinal/fisiopatologia
13.
ACS Appl Mater Interfaces ; 11(17): 15344-15353, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30974942

RESUMO

Myelination by oligodendrocytes (OLs) is a key developmental milestone in terms of the functions of the central nervous system (CNS). Demyelination caused by defects in OLs is a hallmark of several CNS disorders. Although a potential therapeutic strategy involves treatment with the myelin-forming cells, there is no readily available source of these cells. OLs can be differentiated from pluripotent stem cells; however, there is a lack of efficient culture systems that generate functional OLs. Here, we demonstrate biomimetic approaches to promote OL differentiation from human-induced pluripotent stem cells (iPSCs) and to enhance the maturation and myelination capabilities of iPSC-derived OL (iPSC-OL). Functionalization of culture substrates using the brain extracellular matrix (BEM) derived from decellularized human brain tissue enhanced the differentiation of iPSCs into myelin-expressing OLs. Co-culture of iPSC-OL with induced neuronal (iN) cells on BEM substrates, which closely mimics the in vivo brain microenvironment for myelinated neurons, not only enhanced myelination of iPSC-OL but also improved electrophysiological function of iN cells. BEM-functionalized aligned electrospun nanofibrous scaffolds further promoted the maturation of iPSC-OLs, enhanced the production of myelin sheath-like structures by the iPSC-OL, and enhanced the neurogenesis of iN cells. Thus, the biomimetic strategy presented here can generate functional OLs from stem cells and facilitate myelination by providing brain-specific biochemical, biophysical, and structural signals. Our system comprising stem cells and brain tissue from human sources could help in the establishment of human demyelination disease models and the development of regenerative cell therapy for myelin disorders.


Assuntos
Encéfalo/metabolismo , Matriz Extracelular/química , Bainha de Mielina/fisiologia , Diferenciação Celular , Linhagem Celular , Técnicas de Cocultura , Fenômenos Eletrofisiológicos , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Proteína Básica da Mielina/metabolismo , Nanofibras/química , Neurogênese , Neurônios/citologia , Neurônios/metabolismo , Neurotransmissores/farmacologia , Oligodendroglia/citologia , Oligodendroglia/efeitos dos fármacos , Oligodendroglia/metabolismo
14.
Neurobiol Dis ; 127: 554-562, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30951850

RESUMO

Apoptosis is triggered in the developing mammalian brain by sedative, anesthetic or antiepileptic drugs during late gestation and early life. Whether human children are vulnerable to this toxicity mechanism remains unknown, as there are no imaging techniques to capture it. Apoptosis is characterized by distinct structural features, which affect the way damaged tissue scatters ultrasound compared to healthy tissue. We evaluated whether apoptosis, triggered by the anesthetic sevoflurane in the brains of neonatal rhesus macaques, can be detected using quantitative ultrasound (QUS). Neonatal (n = 15) rhesus macaques underwent 5 h of sevoflurane anesthesia. QUS images were obtained through the sagittal suture at 0.5 and 6 h. Brains were collected at 8 h and examined immunohistochemically to analyze apoptotic neuronal and oligodendroglial death. Significant apoptosis was detected in white and gray matter throughout the brain, including the thalamus. We measured a change in the effective scatterer size (ESS), a QUS biomarker derived from ultrasound echo signals obtained with clinical scanners, after sevoflurane-anesthesia in the thalamus. Although initial inclusion of all measurements did not reveal a significant correlation, when outliers were excluded, the change in the ESS between the pre- and post-anesthesia measurements correlated strongly and proportionally with the severity of apoptotic death. We report for the first time in vivo changes in QUS parameters, which may reflect severity of apoptosis in the brains of infant nonhuman primates. These findings suggest that QUS may enable in vivo studies of apoptosis in the brains of human infants following exposure to anesthetics, antiepileptics and other brain injury mechanisms.


Assuntos
Apoptose/fisiologia , Encéfalo/diagnóstico por imagem , Sevoflurano/farmacologia , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Feminino , Macaca mulatta , Masculino , Neurônios/efeitos dos fármacos , Oligodendroglia/efeitos dos fármacos , Ultrassonografia
15.
eNeuro ; 6(2)2019.
Artigo em Inglês | MEDLINE | ID: mdl-31028086

RESUMO

Blocking inhibitory factors within CNS demyelinating lesions is regarded as a promising strategy to promote remyelination. Bone morphogenetic protein 4 (BMP4) is an inhibitory factor present in demyelinating lesions. Noggin, an endogenous antagonist to BMP, has previously been shown to increase the number of oligodendrocytes and promote remyelination in vivo. However, it remains unclear how BMP4 signaling inhibits remyelination. Here we investigated the downstream signaling pathway that mediates the inhibitory effect that BMP4 exerts upon remyelination through pharmacological and transgenic approaches. Using the cuprizone mouse model of central demyelination, we demonstrate that selectively blocking BMP4 signaling via the pharmacological inhibitor LDN-193189 significantly promotes oligodendroglial differentiation and the extent of remyelination in vivo This was accompanied by the downregulation of transcriptional targets that suppress oligodendrocyte differentiation. Further, selective deletion of BMP receptor type IA (BMPRIA) within primary mouse oligodendrocyte progenitor cells (OPCs) significantly enhanced their differentiation and subsequent myelination in vitro Together, the results of this study identify that BMP4 signals via BMPRIA within OPCs to inhibit oligodendroglial differentiation and their capacity to myelinate axons, and suggest that blocking the BMP4/BMPRIA pathway in OPCs is a promising strategy to promote CNS remyelination.


Assuntos
Proteína Morfogenética Óssea 4/metabolismo , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/metabolismo , Doenças Desmielinizantes/metabolismo , Células-Tronco Neurais/metabolismo , Oligodendroglia/metabolismo , Remielinização , Transdução de Sinais , Animais , Proteína Morfogenética Óssea 4/antagonistas & inibidores , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/deficiência , Diferenciação Celular/efeitos dos fármacos , Doenças Desmielinizantes/tratamento farmacológico , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Células-Tronco Neurais/efeitos dos fármacos , Oligodendroglia/efeitos dos fármacos , Pirazóis/farmacologia , Pirimidinas/farmacologia , Remielinização/efeitos dos fármacos
16.
Histochem Cell Biol ; 152(2): 119-131, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31016368

RESUMO

Oligodendrocyte degeneration is a hallmark of multiple sclerosis pathology, and protecting oligodendrocytes and myelin is likely to be of clinical relevance. Traditionally, oligodendrocyte and myelin degeneration are viewed as a direct consequence of an inflammatory attack, but metabolic defects might be equally important. Appropriate animal models to study the interplay of inflammation and metabolic injury are, therefore, needed. Here, we describe that in spite of its immunosuppressive effects, a continuous intoxication with cuprizone allows the induction of active experimental autoimmune encephalomyelitis (EAE) by myelin oligodendrocyte glycoprotein (MOG35-55) immunization. Although the clinical severity of EAE is ameliorated in cuprizone-intoxicated mice, the recruitment of granulocytes, and especially, CD3+ lymphocytes into the forebrain is triggered by the cuprizone insult. Such combined lesions are further characterized by oligodendrocyte apoptosis and microglia activation, closely mimicking type III multiple sclerosis lesions. In summary, we provide a protocol that allows to study the direct interplay of immune-mediated and metabolic oligodendrocyte injury and its consequences for the cerebral white and grey matters.


Assuntos
Cuprizona/toxicidade , Encefalomielite Autoimune Experimental/induzido quimicamente , Administração Oral , Animais , Apoptose/efeitos dos fármacos , Apoptose/imunologia , Cuprizona/administração & dosagem , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/patologia , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Glicoproteína Mielina-Oligodendrócito/imunologia , Oligodendroglia/efeitos dos fármacos , Oligodendroglia/imunologia , Oligodendroglia/patologia , Fragmentos de Peptídeos/imunologia
17.
J Mol Histol ; 50(3): 263-271, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31016544

RESUMO

Oxidative stress with mitochondrial defects has a central role in the development and deterioration of Multiple sclerosis (MS). According to new findings of the effects of metformin on mitochondrial function, has attracted a lot of attention. Furthermore, it is suggested that metformin exerts its beneficial influence through AMP-activated protein kinase (AMPK) pathway. In the current study, we investigated the possible protective effects of metformin on oxidative stress and mitochondrial function by activating the AMPK pathway in the cuprizone-induced demyelination. Mice were fed with cuprizone for 6 weeks. Animals simultaneously received metformin. After sacrificing animals, myelinations, and gliosis, changes in transcription factor and biochemical analysis were assessed. Transmission electron microscopy and luxol fast blue staining revealed that the myelinated axons within corpus callosum of cuprizone-induced demyelination animals increased after administration of metformin. Metformin also upregulated the expression of mitochondrial biogenesis genes. Furthermore, the biochemical analysis demonstrated that metformin ameliorated the oxidative stress induced by cuprizone. Immunohistochemistry analysis showed that astrogliosis and microgliosis were decreased after metformin administration while it enhanced the number of oligodendrocytes. Our data implicated that metformin exerts its therapeutic effects on MS by AMPK signaling improved mitochondrial homeostasis and protected oligodendrocytes.


Assuntos
Metformina/administração & dosagem , Mitocôndrias/efeitos dos fármacos , Esclerose Múltipla/tratamento farmacológico , Proteínas Quinases/genética , Animais , Axônios/efeitos dos fármacos , Axônios/patologia , Cuprizona/toxicidade , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/tratamento farmacológico , Doenças Desmielinizantes/patologia , Modelos Animais de Doenças , Hemostasia/efeitos dos fármacos , Hemostasia/genética , Humanos , Camundongos , Mitocôndrias/genética , Esclerose Múltipla/induzido quimicamente , Esclerose Múltipla/patologia , Oligodendroglia/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
18.
Glia ; 67(7): 1374-1384, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30861188

RESUMO

It is now well-established that the macrophage and microglial response to CNS demyelination influences remyelination by removing myelin debris and secreting a variety of signaling molecules that influence the behaviour of oligodendrocyte progenitor cells (OPCs). Previous studies have shown that changes in microglia contribute to the age-related decline in the efficiency of remyelination. In this study, we show that microglia increase their expression of the proteoglycan NG2 with age, and that this is associated with an altered micro-niche generated by aged, but not young, microglia that can divert the differentiation OPCs from oligodendrocytes into astrocytes in vitro. We further show that these changes in ageing microglia are generated by exposure to high levels of TGFß. Thus, our findings suggest that the rising levels of circulating TGFß known to occur with ageing contribute to the age-related decline in remyelination by impairing the ability of microglia to promote oligodendrocyte differentiation from OPCs, and therefore could be a potential therapeutic target to promote remyelination.


Assuntos
Senescência Celular/fisiologia , Microglia/metabolismo , Células Precursoras de Oligodendrócitos/metabolismo , Oligodendroglia/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Fatores Etários , Animais , Animais Recém-Nascidos , Diferenciação Celular/fisiologia , Células Cultivadas , Senescência Celular/efeitos dos fármacos , Sistema Nervoso Central/efeitos dos fármacos , Sistema Nervoso Central/metabolismo , Relação Dose-Resposta a Droga , Microglia/efeitos dos fármacos , Células Precursoras de Oligodendrócitos/efeitos dos fármacos , Oligodendroglia/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
19.
Ann Clin Transl Neurol ; 6(2): 392-396, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30847372

RESUMO

Our objective was to examine the brain biopsies by histopathology and investigate the prognosis of patients with myelin oligodendrocyte glycoprotein antibody-associated demyelinating pseudotumor. The clinical, MRI, and histological features of two patients with myelin oligodendrocyte glycoprotein antibody-associated demyelinating pseudotumor were reviewed. Both patients were treated with steroid plus rituximab and followed up. The brain biopsies of both cases revealed T cells, macrophages, and complement-mediated demyelination, which was in accord with multiple sclerosis-like pathology. Moreover, both cases showed favorable response to steroid plus rituximab therapy. Our cases add a new variant to the myelin oligodendrocyte glycoprotein-encephalomyelitis spectrum, which favorably responds to immunotherapy.


Assuntos
Autoanticorpos/efeitos adversos , Doenças Desmielinizantes/induzido quimicamente , Glicoproteína Mielina-Oligodendrócito/metabolismo , Malformações do Sistema Nervoso/patologia , Doenças Desmielinizantes/diagnóstico , Doenças Desmielinizantes/patologia , Encefalomielite/tratamento farmacológico , Encefalomielite/patologia , Humanos , Fatores Imunológicos/metabolismo , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/patologia , Glicoproteína Associada a Mielina/metabolismo , Malformações do Sistema Nervoso/tratamento farmacológico , Oligodendroglia/efeitos dos fármacos , Oligodendroglia/metabolismo
20.
Med Sci Monit ; 25: 1729-1739, 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30840612

RESUMO

BACKGROUND We aimed to explore the involvement of adenosine 1 adenosine receptor (A1AR) in hypoxia-induced poor differentiation of oligodendrocytes (OLs), and the underlying mechanism of caffeine treatment in hypoxic injuries. MATERIAL AND METHODS Real-time polymerase chain reaction (RT-PCR) was used to assess the alterations of AR expression in cultured hypoxic OLs with or without caffeine treatment. Then, intracellular alterations of Ca²âº concentrations ([Ca²âº) were detected by confocal Fluo-3 imaging. The subsequent changes of myelin related protein expression were determined by western blot and immunofluorescence. RESULTS Three hours after hypoxia, significantly upregulated expression of A1AR was observed, accompanied with significantly decreased expression of oligodendrocyte transcription factor (Olig2). In addition, either hypoxia stimulation or 100 µM adenosine induced apparent elevation of resting [Ca²âº] in cultured OLs. However, pretreatment with DPCPX (A1AR selective antagonist) or caffeine abolished the [Ca²âº] increase, and the subsequent adenosine of high dose induced Ca²âº activity in developing OLs. Furthermore, caffeine or DPCPX improved the expression MBP and CNPase proteins after hypoxia stimulation, which resulted in the morphological maturation of OLs. CONCLUSIONS Caffeine treatment exerted protective effects on neonatal hypoxia injuries. It prevented Ca²âº overload injury, kept Ca²âº homeostasis in hypoxic developing OLs, and facilitated optimal expression of myelin related proteins by inhibiting A1AR in vitro. This study also provided experimental evidence for clinical application of caffeine in early treatment of neonatal hypoxia, and highlighted the potential significance of A1AR in anti-hypoxic drug discovery.


Assuntos
Cafeína/farmacologia , Oligodendroglia/efeitos dos fármacos , Receptor A1 de Adenosina/efeitos dos fármacos , Adenosina/metabolismo , Animais , Cafeína/metabolismo , Cálcio/metabolismo , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , China , Homeostase/efeitos dos fármacos , Hipóxia/tratamento farmacológico , Hipóxia/fisiopatologia , Bainha de Mielina/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Detecção de Cálcio/metabolismo , Receptores Purinérgicos P1/efeitos dos fármacos , Receptores Purinérgicos P1/metabolismo
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