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1.
Neurobiol Dis ; 156: 105422, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34126164

RESUMO

Synthetic glucocorticoids (sGCs) such as dexamethasone (DEX), while used to mitigate inflammation and disease progression in premature infants with severe bronchopulmonary dysplasia (BPD), are also associated with significant adverse neurologic effects such as reductions in myelination and abnormalities in neuroanatomical development. Ciclesonide (CIC) is a sGC prodrug approved for asthma treatment that exhibits limited systemic side effects. Carboxylesterases enriched in the lower airways convert CIC to the glucocorticoid receptor (GR) agonist des-CIC. We therefore examined whether CIC would likewise activate GR in neonatal lung but have limited adverse extra-pulmonary effects, particularly in the developing brain. Neonatal rats were administered subcutaneous injections of CIC, DEX or vehicle from postnatal days 1-5 (PND1-PND5). Systemic effects linked to DEX exposure, including reduced body and brain weight, were not observed in CIC treated neonates. Furthermore, CIC did not trigger the long-lasting reduction in myelin basic protein expression in the cerebral cortex nor cerebellar size caused by neonatal DEX exposure. Conversely, DEX and CIC were both effective at inducing the expression of select GR target genes in neonatal lung, including those implicated in lung-protective and anti-inflammatory effects. Thus, CIC is a promising, novel candidate drug to treat or prevent BPD in neonates given its activation of GR in neonatal lung and limited adverse neurodevelopmental effects. Furthermore, since sGCs such as DEX administered to pregnant women in pre-term labor can adversely affect fetal brain development, the neurological-sparing properties of CIC, make it an attractive alternative for DEX to treat pregnant women severely ill with respiratory illness, such as with asthma exacerbations or COVID-19 infections.


Assuntos
Cerebelo/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Glucocorticoides , Pulmão/efeitos dos fármacos , Pregnenodionas/farmacologia , Pró-Fármacos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Anti-Inflamatórios/farmacologia , Peso Corporal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/crescimento & desenvolvimento , Dexametasona/farmacologia , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Proteína Básica da Mielina/biossíntese , Tamanho do Órgão/efeitos dos fármacos , Gravidez , Ratos , Ratos Sprague-Dawley , Receptores de Glucocorticoides/efeitos dos fármacos , Tratamento Farmacológico da COVID-19
2.
Sci Rep ; 11(1): 6551, 2021 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-33753806

RESUMO

Oligodendrocytes (OLs), myelin-producing glia in the central nervous system (CNS), produce a myelin extension that enwraps axons to facilitate action potential propagation. An effective approach to induce oligodendrogenesis and myelination is important to foster CNS development and promote myelin repair in neurological diseases. Hericium (H.) erinaceus, an edible and culinary-medicinal mushroom, has been characterized as having neuroprotective activities. However, its effect on OL differentiation has not yet been uncovered. In this study using oligodendrocyte precursor cell (OPC) cultures and an ex vivo cerebellar slice system, we found that the extract from H. erinaceus mycelium (HEM) not only promoted the differentiation of OPCs to OLs in the differentiation medium, but also increased the level of myelin basic protein (MBP) on neuronal fibers. Moreover, daily oral administration of HEM into neonatal rat pups for 7 days enhanced MBP expression and OLs in the corpus callosum of the postnatal rat brain. The effect of HEM-derived bioactive compounds, the diterpenoid xylosides erinacine A (HeA) and HeC and a sesterterpene with 5 isoprene units called HeS, were further evaluated. The results showed that HeA and HeS more potently stimulated MBP expression in OLs and increased the number of OLs. Moreover, overlap between MBP immunoreactivity and neuronal fibers in cultured cerebellar tissue slices was significantly increased in the presence of HeA and HeS. In summary, our findings indicate that HEM extract and its ingredients HeA and HeS display promising functional effects and promote OL maturation, providing insights into their potential for myelination in neurodevelopmental disorders.


Assuntos
Produtos Biológicos/farmacologia , Hericium/metabolismo , Micélio , Proteína Básica da Mielina/biossíntese , Oligodendroglia/efeitos dos fármacos , Oligodendroglia/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular , Células Cultivadas , Expressão Gênica , Estrutura Molecular , Proteína Básica da Mielina/genética , Oligodendroglia/citologia , Ratos
3.
Acta Neurobiol Exp (Wars) ; 79(4): 367-373, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31885393

RESUMO

The national incidence of neonatal abstinence syndrome has dramatically increased over the last decade due to an increase in antenatal opioid exposure. Recent human and animal studies suggest that antenatal opioid exposure impacts the developing brain. The purpose of this study is to evaluate the effects of perinatal methadone exposure on myelination in multiple regions in the developing rat brain. Pregnant Sprague-Dawley rats were randomly assigned into three experimental groups and subsequently exposed to drinking water alone or drinking water containing methadone from 7 days post coitum through day 7 or through day 19 after delivery. Two male neonatal rats were randomly selected from each litter and terminated at day 19. The cerebral cortex, hippocampus, cerebellum, and brainstem were dissected and analyzed for three myelin specific proteins - CNP, PLP, and MBP - by Western blot analysis. All pups with exposure to methadone demonstrated decreased expression of CNP, PLP, and MBP in the cerebral cortex and hippocampus. In the cerebellum, PLP expression was down­regulated without apparent alteration of CNP and MBP expression. PLP and MBP expression, but not CNP expression, were significantly inhibited in the brainstem. Compared to the pups with postnatal methadone exposure via maternal milk through day 7, partial recovery of CNP and PLP expression only occurred in the cerebral cortices of the pups exposed through day 19. The findings show that antenatal opioid exposure in rat pups is associated with regionally­specific alterations in brain myelination that diversely affects myelin proteins.


Assuntos
2',3'-Nucleotídeo Cíclico 3'-Fosfodiesterase/biossíntese , Encéfalo/efeitos dos fármacos , Metadona/toxicidade , Proteína Básica da Mielina/biossíntese , Proteína Proteolipídica de Mielina/biossíntese , Síndrome de Abstinência Neonatal/metabolismo , Efeitos Tardios da Exposição Pré-Natal , 2',3'-Nucleotídeo Cíclico 3'-Fosfodiesterase/genética , Animais , Encéfalo/embriologia , Feminino , Masculino , Proteína Básica da Mielina/genética , Proteína Proteolipídica de Mielina/genética , Bainha de Mielina/fisiologia , Síndrome de Abstinência Neonatal/etiologia , Oligodendroglia/metabolismo , Especificidade de Órgãos , Gravidez , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
4.
Sci Rep ; 9(1): 13299, 2019 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-31527712

RESUMO

Human mutations in carnitine palmitoyl transferase 1A (CPT1A) are correlated with a remarkably low prevalence of multiple sclerosis (MS) in Inuits (P479L) and Hutterites (G710E). To elucidate the role of CPT1A, we established a Cpt1a P479L mouse strain and evaluated its sensitivity to experimental autoimmune encephalomyelitis (EAE) induction. Since CPT1a is a key molecule in lipid metabolism, we compared the effects of a high-fat diet (HFD) and normal diet (ND) on disease progression. The disease severity increased significantly in WT mice compared to that in Cpt1 P479L mice. In addition, WT mice receiving HFD showed markedly exacerbated disease course when compared either with Cpt1a P479L mice receiving HFD or WT control group receiving ND. Induction of EAE caused a significant decrease of myelin basic protein expression in the hindbrain of disease affected WT mice in comparison to Cpt1a P479L mice. Further, WT mice showed increased expression of oxidative stress markers like Nox2 and Ho-1, whereas expression of mitochondrial antioxidants regulator Pgc1α was increased in Cpt1a P479L mice. Our results suggest that, lipids metabolism play an important role in EAE, as shown by the higher severity of disease progression in both WT EAE and WT EAF HFD-fed mice in contrast to their counterpart Cpt1a P479L mutant mice. Interestingly, mice with downregulated lipid metabolism due to the Cpt1a P479L mutation showed resistance to EAE induction. These findings support a key role for CPT1A in the development of EAE and could be a promising target in MS treatment.


Assuntos
Carnitina O-Palmitoiltransferase/genética , Encefalomielite Autoimune Experimental/genética , Predisposição Genética para Doença/genética , Metabolismo dos Lipídeos/genética , Animais , Dieta Hiperlipídica , Feminino , Heme Oxigenase-1/metabolismo , Humanos , Metabolismo dos Lipídeos/fisiologia , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Esclerose Múltipla/genética , Proteína Básica da Mielina/biossíntese , NADPH Oxidase 2/metabolismo , Estresse Oxidativo/fisiologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Rombencéfalo/metabolismo
5.
BMC Neurosci ; 20(1): 33, 2019 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-31291887

RESUMO

BACKGROUND: Hypothalamic inflammation including astrogliosis and microglia activation occurs after intake of high fat diet (HFD) in rodent models or in obese individuals. However, the effect of chronic HFD feeding on oligodendrocytes (OLGs), a myelin-producing glial population in the central nervous system (CNS), remains unclear. In this study, we used 8-week old male C57BL/6 mice fed by HFD for 3-6 months to induce chronic obesity. RESULTS: The transmission electron microscopy imaging analysis showed that the integrity of hypothalamic myelin was disrupted after HFD feeding for 4 and 6 months. Moreover, the accumulation of Iba1+-microglia with an amoeboid hypertrophic form was continually observed in arcuate nucleus of HFD-fed mice during the entire feeding time period. Interleukin-33 (IL-33), a tissue alarmin upon injury to the CNS, was detected with an increased level in hypothalamus after HFD feeding for 3 and 4 months. Furthermore, the in vitro study indicated that exposure of mature OLGs to IL-33 impaired OLG cell structure along with a decline in the expression of myelin basic protein. CONCLUSIONS: Altogether, our findings demonstrate that chronic HFD feeding triggers hypothalamic myelin disruption in accompany with IL-33 upregulation and prolonged microglial activation in hypothalamus. Given that the addition of exogenous IL-33 was harmful for the maturation of OLGs, an increase in IL-33 by chronic HFD feeding might contribute to the induction of hypothalamic myelin disruption.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Hipotálamo/metabolismo , Interleucina-33/metabolismo , Bainha de Mielina/patologia , Regulação para Cima , Animais , Núcleo Arqueado do Hipotálamo/metabolismo , Núcleo Arqueado do Hipotálamo/patologia , Hipotálamo/patologia , Masculino , Camundongos , Proteína Básica da Mielina/biossíntese , Bainha de Mielina/metabolismo , Oligodendroglia/metabolismo , Oligodendroglia/patologia , Cultura Primária de Células , Ratos , Fatores de Tempo
6.
J Neuroimmunol ; 333: 476958, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31103935

RESUMO

The use of growth factors is considered to be one of the promising therapeutic strategies for multiple sclerosis (MS). Various studies have shown that platelet-rich plasma (PRP), a bioproduct of concentrated platelets, contains a variety of growth factors such as insulin-like growth factor 1 (IGF-1), platelet-derived growth factor (PDGF), epithelial growth factor (EGF), and transforming growth factor ß (TGF-ß). The therapeutic roles of PRP, with regard to a wide range of growth factors, on the nervous system have been shown in a limited number of studies. This study aimed to investigate the therapeutic effect of PRP in experimental autoimmune encephalomyelitis (EAE) mouse model of MS. PRP was prepared and intrathecally injected into the EAE mice. The EAE scoring test, the modified neurological severity score (mNSS) test, luxol fast blue and hematoxylin and eosin staining, real-time PCR, and western blotting were used for studying the effect of PRP on the motosensory function, remyelination, inflammatory cell infiltration, gliosis, and inflammatory cytokines expression. PRP administration in treated animals improved the functional abilities, remyelination, and oligodendrogenesis compared to the EAE mice. Furthermore, high numbers of microglia, astrocytes and infiltrating inflammatory cells and also the expression of proinflammatory cytokines were reversed after PRP therapy. In conclusion, these data suggest the PRP as a potential candidate for MS treatment.


Assuntos
Encefalomielite Autoimune Experimental/terapia , Plasma Rico em Plaquetas , Animais , Encefalomielite Autoimune Experimental/patologia , Feminino , Gliose/patologia , Gliose/prevenção & controle , Inflamação , Injeções Espinhais , Interleucina-1beta/biossíntese , Interleucina-1beta/genética , Interleucina-6/biossíntese , Interleucina-6/genética , Camundongos , Camundongos Endogâmicos C57BL , Proteína Básica da Mielina/biossíntese , Proteína Básica da Mielina/genética , Plasma Rico em Plaquetas/imunologia , Medula Espinal/patologia , Regulação para Cima
7.
Anat Histol Embryol ; 48(1): 74-86, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30450567

RESUMO

The optic nerve (ON) is an important organ in the visual system of animals, which transfers electrical impulses towards the brain from the retina. High enrichment of glial cells in ON is known to support neuron and regulate retinal homoeostasis. However, research on immunohistochemical of glial cells proteins in the camel is scanty in available literature. Hence, the current work is an attempt to investigate the histomorphology of camel ON with regard to the expression patterns of glial fibrillary acidic protein (GFAP), myelin basic protein (MBP) and Iba1 for the three glial subtypes, namely astrocytes, oligodendrocytes and microglia, respectively. Optic nerves from fourteen dromedary camels were dissected and preserved in 10% formalin. Then, the paraffin-embedding sections were subjected for histochemical and immunohistochemical analysis. Our results demonstrated that ON axons aggregate into fascicles that surrounded by light and densely stained glial cells. Then, we examined the myelin sheath using Heidenhain's and Mallory's phosphotungstic acid staining. Immunoassay results revealed that GFAP is enriched in the ON and distributed evenly, whereas MBP and Iba1 were present at scanty levels. Further analysis of mRNA level of GFAP, MBP and Iba1 in the ON confirmed an elevation of GFAP expression compared to MBP and Iba1. We further found partial co-localization of different types of glial cells that reflect their coordinated function in the ON. Although our data provide the first evidence for differential expression pattern of glial proteins, further molecular studies still required to reveal the specific function of these molecules in the camel ON.


Assuntos
Astrócitos/metabolismo , Camelus/anatomia & histologia , Proteínas de Ligação a DNA/biossíntese , Proteína Glial Fibrilar Ácida/biossíntese , Microglia/metabolismo , Microscopia/veterinária , Proteína Básica da Mielina/biossíntese , Neuroglia/metabolismo , Oligodendroglia/metabolismo , Nervo Óptico/citologia , Sequência de Aminoácidos , Animais , Axônios/metabolismo , Feminino , Masculino , Bainha de Mielina/ultraestrutura , Nervo Óptico/metabolismo
8.
Neuropharmacology ; 148: 31-39, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30553827

RESUMO

Organophosphorus compound (OP)-induced delayed neuropathy (OPIDN) is characterized by distal axonal degeneration and demyelination of the central and peripheral axons, which leads to progressive muscle weakness, ataxia and paralysis in several days after OP intoxication. This study aimed to investigate the possible use of an imidazole fungicide miconazole as a novel therapy for OPIDN. Adult hens, the most commonly used animal models in OPIDN studies, were orally given tri-o-cresyl phosphate (TOCP). We showed that miconazole, which was administered daily to hens beginning on the 7th day after TOCP exposure, drastically ameliorated the neurotoxic symptoms and histopathological damages in spinal cord and sciatic nerves. Mechanistically, miconazole inhibited the TOCP-induced activation of ErbB/Akt signaling, and enhanced the myelin basic protein (MBP) expression. In a glial cell model sNF96.2 cells, miconazole restored the TOCP-inhibited MBP expression, and promoted cell differentiation as well as cell migration by inhibiting the activation of ErbB/Akt signaling pathway. In sum, miconazole, a synthetic imidazole fungicide, could ameliorate the symptoms and histopathological changes of OPIDN, probably by promoting glial cell differentiation and migration to enhance myelination via inhibiting the activation of ErbB/Akt. Thus, miconazole is a promising candidate therapy for the clinical treatment of OPIDN.


Assuntos
Doenças Desmielinizantes/prevenção & controle , Miconazol/farmacologia , Transdução de Sinais/efeitos dos fármacos , Tritolil Fosfatos/toxicidade , Animais , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Galinhas , Feminino , Humanos , Proteína Básica da Mielina/biossíntese , Síndromes Neurotóxicas/prevenção & controle , Proteínas Oncogênicas v-erbB/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Nervo Isquiático/efeitos dos fármacos , Nervo Isquiático/patologia , Medula Espinal/efeitos dos fármacos , Medula Espinal/patologia , Tritolil Fosfatos/antagonistas & inibidores
9.
J Neurosci ; 38(32): 7088-7099, 2018 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-29976621

RESUMO

Methods to promote myelin regeneration in response to central myelin loss are essential to prevent the progression of clinical disability in demyelinating diseases. The neurotrophin brain-derived neurotrophic factor (BDNF) is known to promote myelination during development via oligodendrocyte expressed TrkB receptors. Here, we use a structural mimetic of BDNF to promote myelin regeneration in a preclinical mouse model of central demyelination. In female mice, we show that selective targeting of TrkB with the BDNF-mimetic enhances remyelination, increasing oligodendrocyte differentiation, the frequency of myelinated axons, and myelin sheath thickness after a demyelinating insult. Treatment with exogenous BDNF exerted an attenuated effect, increasing myelin sheath thickness only. Further, following conditional deletion of TrkB from premyelinating oligodendrocytes, we show the effects of the BDNF-mimetic on oligodendrocyte differentiation and remyelination are lost, indicating these are dependent on oligodendrocyte expression of TrkB. Overall, these studies demonstrate that targeting oligodendrocyte TrkB promotes in vivo remyelination in the brain.SIGNIFICANCE STATEMENT Novel strategies to promote myelin regeneration are required to prevent progressive neurodegeneration and clinical disability in patients with central demyelinating disease. Here, we test whether selectively targeting the TrkB receptor on the myelin-producing oligodendrocytes, can promote remyelination in the brain. Using a structural mimetic of its native ligand, BDNF, we show that stimulation of TrkB enhances remyelination, increasing oligodendrocyte differentiation, the frequency of myelinated axons and thickness of the myelin sheath following a demyelinating insult. Further, we show that these effects are dependent on the phosphorylation of oligodendrocyte expressed TrkB receptors in vivo Overall, we demonstrate that selective targeting of TrkB has therapeutic potential to promote remyelination in the brain.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/uso terapêutico , Encéfalo/efeitos dos fármacos , Doenças Desmielinizantes/tratamento farmacológico , Glicoproteínas de Membrana/agonistas , Terapia de Alvo Molecular , Bainha de Mielina/metabolismo , Oligodendroglia/efeitos dos fármacos , Remielinização/efeitos dos fármacos , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Divisão Celular/efeitos dos fármacos , Corpo Caloso/metabolismo , Corpo Caloso/patologia , Cuprizona/toxicidade , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/patologia , Feminino , Bombas de Infusão Implantáveis , Infusões Intraventriculares , Masculino , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína Básica da Mielina/biossíntese , Células-Tronco Neurais/efeitos dos fármacos , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/uso terapêutico , Fosforilação , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteínas Tirosina Quinases/metabolismo , Organismos Livres de Patógenos Específicos
10.
Cell Calcium ; 73: 1-10, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29880193

RESUMO

Oligodendrocytes in the CNS myelinate neuronal axons, facilitating rapid propagation of action potentials. Myelin basic protein (MBP) is an essential component of myelin and its absence results in severe hypomyelination. In oligodendrocyte lineage cell (OLC) monocultures MBP synthesis starts at DIV4. Ouabain (10 nM), a Na+,K+-ATPase (NKA) blocker, stimulates MBP synthesis. As OLCs express the α2 isoform of NKA (α2-NKA) that has a high affinity for ouabain, we hypothesized that α2-NKA mediates this effect. Knockdown of α2-NKA with small interfering (si)RNA (α2-siRNA) significantly potentiated MBP synthesis at DIV4 and 5. This effect was completely blocked by KB-R7943 (1 µM), a Na+,Ca2+ exchanger (NCX) antagonist. α2-NKA ablation increased the frequency of NCX-mediated spontaneous Ca2+ transients ([Ca2+]t) at DIV4, whereas in control OLC cultures comparable frequency of [Ca2+]t was observed at DIV5. At DIV6 almost no [Ca2+]t were observed either in control or in α2-siRNA-treated cultures. Immunocytochemical analyses showed that α2-NKA co-localizes with MBP in proximal processes of immature OLCs but is only weakly present in MBP-enriched membrane sheets. Knockdown of α2-NKA in cortical slice cultures did not change MBP levels but reduced co-localization of neurofilament- and MBP-positive compartments. We conclude that α2-NKA activity in OLCs affects NCX-mediated [Ca2+]t and the onset of MBP synthesis. We suggest therefore that neuronal activity, presumably in form of local extracellular [K+] changes, might locally influence NCX-mediated [Ca2+]t in OLC processes thus triggering local MBP synthesis in the vicinity of an active axon.


Assuntos
Linhagem da Célula/fisiologia , Proteína Básica da Mielina/biossíntese , Oligodendroglia/metabolismo , Trocador de Sódio e Cálcio/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Linhagem da Célula/efeitos dos fármacos , Células Cultivadas , Inibidores Enzimáticos/farmacologia , Isoenzimas/antagonistas & inibidores , Isoenzimas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Oligodendroglia/efeitos dos fármacos , Técnicas de Cultura de Órgãos , Ouabaína/farmacologia , Trocador de Sódio e Cálcio/antagonistas & inibidores , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , Tioureia/análogos & derivados , Tioureia/farmacologia
11.
J Cell Sci ; 131(9)2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29622601

RESUMO

In the central nervous system, oligodendroglial expression of myelin basic protein (MBP) is crucial for the assembly and structure of the myelin sheath. MBP synthesis is tightly regulated in space and time, particularly at the post-transcriptional level. We have identified the DEAD-box RNA helicase DDX5 (also known as p68) in a complex with Mbp mRNA in oligodendroglial cells. Expression of DDX5 is highest in progenitor cells and immature oligodendrocytes, where it localizes to heterogeneous populations of cytoplasmic ribonucleoprotein (RNP) complexes associated with Mbp mRNA in the cell body and processes. Manipulation of the amount of DDX5 protein inversely affects the level of MBP. We present evidence that DDX5 is involved in post-transcriptional regulation of MBP protein synthesis, with implications for oligodendroglial development. In addition, knockdown of DDX5 results in an increased abundance of MBP isoforms containing exon 2 in immature oligodendrocytes, most likely by regulating alternative splicing of Mbp Our findings contribute to the understanding of the complex nature of MBP post-transcriptional control in immature oligodendrocytes where DDX5 appears to affect the abundance of MBP proteins via distinct but converging mechanisms.


Assuntos
RNA Helicases DEAD-box/metabolismo , Proteína Básica da Mielina/metabolismo , Oligodendroglia/metabolismo , Animais , Citoplasma/metabolismo , RNA Helicases DEAD-box/genética , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Proteína Básica da Mielina/biossíntese , Proteína Básica da Mielina/genética , Processamento Pós-Transcricional do RNA
12.
J Neuroinflammation ; 14(1): 250, 2017 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-29246262

RESUMO

BACKGROUND: The G protein-coupled receptor EBI2 (Epstein-Barr virus-induced gene 2) is activated by 7α, 25-dihydroxycholesterol (7α25HC) and plays a role in T cell-dependant antibody response and B cell migration. Abnormal EBI2 signaling is implicated in a range of autoimmune disorders; however, its role in the CNS remains poorly understood. METHODS: Here we characterize the role of EBI2 in myelination under normal and pathophysiological conditions using organotypic cerebellar slice cultures and EBI2 knock-out (KO) animals. RESULTS: We find that MBP expression in brains taken from EBI2 KO mice is delayed compared to those taken from wild type (WT) mice. In agreement with these in vivo findings, we show that antagonism of EBI2 reduces MBP expression in vitro. Importantly, we demonstrate that EBI2 activation attenuates lysolecithin (LPC)-induced demyelination in mouse organotypic slice cultures. Moreover, EBI2 activation also inhibits LPC-mediated release of pro-inflammatory cytokines such as IL6 and IL1ß in cerebellar slices. CONCLUSIONS: These results, for the first time, display a role for EBI2 in myelin development and protection from demyelination under pathophysiological conditions and suggest that modulation of this receptor may be beneficial in neuroinflammatory and demyelinating disorders such as multiple sclerosis.


Assuntos
Cerebelo/metabolismo , Doenças Desmielinizantes/metabolismo , Bainha de Mielina/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animais , Doenças Desmielinizantes/induzido quimicamente , Lisofosfatidilcolinas/toxicidade , Camundongos , Camundongos Knockout , Proteína Básica da Mielina/biossíntese , Técnicas de Cultura de Órgãos
13.
J Appl Toxicol ; 37(4): 479-484, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27610592

RESUMO

Evidence continues to increase linking autoimmunity and other complex diseases to the chemicals commonly found in our environment. Bisphenol A (BPA) is a synthetic monomer used widely in many forms, from food containers to toys, medical products and many others. The potential for BPA to participate as a triggering agent for autoimmune diseases is likely due to its known immunological influences. The goal of this research was to determine if immune reactivity to BPA has any correlation with neurological antibodies. BPA binds to a target enzyme called protein disulfide isomerase (PDI). Myelin basic protein (MBP) and myelin oligodendrocyte glycoprotein (MOG) are neuronal antigens that are target sites for neuroinflammation and neuroautoimmunity. We determined the co-occurrence of anti-MBP and anti-MOG antibodies with antibodies made against BPA bound to human serum albumin in 100 healthy human subjects. Correlation between BPA to PDI, BPA to MOG, BPA to MBP, PDI to MBP and PDI to MOG were all highly statistically significant (P < 0.0001). The outcome of our study suggests that immune reactivity to BPA-human serum albumin and PDI has a high degree of statistical significance with substantial correlation with both MBP and MOG antibody levels. This suggests that BPA may be a trigger for the production of antibodies against PDI, MBP and MOG. Immune reactivity to BPA bound to human tissue proteins may be a contributing factor to neurological autoimmune disorders. Further research is needed to determine the exact relationship of these antibodies with neuroautoimmunities. Copyright © 2016 The Authors Journal of Applied Toxicology Published by John Wiley & Sons Ltd.


Assuntos
Anticorpos Bloqueadores/biossíntese , Anticorpos/metabolismo , Compostos Benzidrílicos/antagonistas & inibidores , Compostos Benzidrílicos/imunologia , Neurônios/imunologia , Fenóis/antagonistas & inibidores , Fenóis/imunologia , Isomerases de Dissulfetos de Proteínas/imunologia , Adolescente , Adulto , Idoso , Anticorpos/farmacologia , Anticorpos Bloqueadores/análise , Doenças Autoimunes/induzido quimicamente , Doenças Autoimunes/imunologia , Autoimunidade/efeitos dos fármacos , Autoimunidade/imunologia , Humanos , Pessoa de Meia-Idade , Proteína Básica da Mielina/biossíntese , Proteína Básica da Mielina/genética , Glicoproteína Mielina-Oligodendrócito/biossíntese , Glicoproteína Mielina-Oligodendrócito/genética , Doenças do Sistema Nervoso/induzido quimicamente , Doenças do Sistema Nervoso/imunologia , Isomerases de Dissulfetos de Proteínas/antagonistas & inibidores , Adulto Jovem
14.
Cell Calcium ; 60(5): 322-330, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27417499

RESUMO

Myelination in the central nervous system depends on axon-oligodendrocyte precursor cell (OPC) interaction. We suggest that myelin synthesis may be influenced by [Na+]i and [Ca2+]i signaling in OPCs. Experiments were performed in mouse cultured OPCs at day in vitro (DIV) 2-6 or acute slices of the corpus callosum at postnatal days (P) 10-30. Synthesis of Myelin Basic Protein (MBP), an "executive molecule of myelin", was used as readout of myelination. Immunohistological data revealed that MBP synthesis in cultured OPCs starts around DIV4. Transient elevations of resting [Ca2+]i and [Na+]i levels were observed in the same temporal window (DIV4-5). At DIV4, but not at DIV2, both extracellular [K+] ([K+]e) elevation (+5mM) and partial Na+,K+-ATPase (NKA) inhibition elicited [Na+]i and [Ca2+]i transients. These responses were blocked with KB-R7943 (1µM), a blocker of Na+-Ca2+ exchanger (NCX), indicating an involvement of NCX which operates in reverse mode. Treatment of OPCs with culture medium containing elevated [K+] (+5mM, 24h) or ouabain (500nM, 24h) increased resting [Ca2+]i and facilitated MBP synthesis. Blockade of NCX with KB-R7943 (1µM, 12h) reduced resting [Ca2+]i and decreased MBP synthesis. Similar to the results obtained in OPC cultures, OPCs in acute callosal slices demonstrated an increase in resting [Ca2+]i and [Na+]i levels during development. NCX blockade induced [Ca2+]i and [Na+]i responses in OPCs at P20-30 but not at P10. We conclude that local [Na+]i and/or membrane potential changes can modulate Ca2+ influx through NCX and in turn MBP synthesis. Thus neuronal activity-induced changes in [K+]e may via NCX and NKA modulate myelination.


Assuntos
Cálcio/metabolismo , Proteína Básica da Mielina/biossíntese , Oligodendroglia/citologia , Transdução de Sinais , Sódio/metabolismo , Células-Tronco/metabolismo , Animais , Células Cultivadas , Íons/metabolismo , Camundongos , Camundongos Endogâmicos C57BL
15.
Mol Ther ; 24(8): 1456-1469, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27203442

RESUMO

Treatment of chronic neurodegenerative diseases such as multiple sclerosis (MS) remains a major challenge. Here we genetically engineer neural stem cells (NSCs) to produce a triply therapeutic cocktail comprising IL-10, NT-3, and LINGO-1-Fc, thus simultaneously targeting all mechanisms underlie chronicity of MS in the central nervous system (CNS): persistent inflammation, loss of trophic support for oligodendrocytes and neurons, and accumulation of neuroregeneration inhibitors. After transplantation, NSCs migrated into the CNS inflamed foci and delivered these therapeutic molecules in situ. NSCs transduced with one, two, or none of these molecules had no or limited effect when injected at the chronic stage of experimental autoimmune encephalomyelitis; cocktail-producing NSCs, in contrast, mediated the most effective recovery through inducing M2 macrophages/microglia, reducing astrogliosis, and promoting axonal integrity and endogenous oligodendrocyte/neuron differentiation. These engineered NSCs simultaneously target major mechanisms underlying chronicity of multiple sclerosis (MS) and encephalomyelitis (EAE), thus representing a novel and potentially effective therapy for the chronic stage of MS, for which there is currently no treatment available.


Assuntos
Autoimunidade , Engenharia Celular , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/imunologia , Expressão Gênica , Células-Tronco Neurais/metabolismo , Transgenes , Animais , Diferenciação Celular , Proliferação de Células , Modelos Animais de Doenças , Progressão da Doença , Encefalomielite Autoimune Experimental/diagnóstico , Encefalomielite Autoimune Experimental/terapia , Feminino , Vetores Genéticos/genética , Interleucina-10/genética , Lentivirus/genética , Macrófagos/metabolismo , Camundongos , Microglia/metabolismo , Esclerose Múltipla/genética , Esclerose Múltipla/imunologia , Esclerose Múltipla/patologia , Esclerose Múltipla/terapia , Proteína Básica da Mielina/biossíntese , Proteínas da Mielina/metabolismo , Fatores de Crescimento Neural/genética , Células-Tronco Neurais/citologia , Neurônios/metabolismo , Neurônios/patologia , Oligodendroglia/citologia , Oligodendroglia/metabolismo , Transplante de Células-Tronco , Transdução Genética
16.
Chemosphere ; 153: 455-61, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27035382

RESUMO

The fungicide imazalil (IMZ) is used extensively to protect vegetable fields, fruit plantations and post-harvest crops from rot. Likely due to its wide-spread use, IMZ is frequently detected in vegetable, fruit, soil and even surface water samples. Even though several previous studies have reported on the neurotoxicity of IMZ, its effects on the neurobehavior of zebrafish have received little attention to date. In this study, we show that the heartbeat and hatchability of zebrafish were significantly influenced by IMZ concentrations of 300 µg L(-1) or higher. Moreover, in zebrafish larvae, locomotor behaviors such as average swimming speed and swimming distance were significantly decreased after exposure to 300 µg L(-1) IMZ for 96 h, and acetylcholinesterase (AChE) expression and activity were consistently inhibited in IMZ-treated fish. Our results further suggest that IMZ could act as a neuroendocrine disruptor by decreasing the expression of neurotoxicity-related genes such as Glial fibrillary acidic protein (Gfap), Myelin basic protein (Mbp) and Sonic hedgehog a (Shha) during early developmental stages of zebrafish. In conclusion, we show that exposure to IMZ has the potential to induce developmental toxicity and locomotor behavior abnormalities during zebrafish development.


Assuntos
Inibidores da Colinesterase/toxicidade , Fungicidas Industriais/toxicidade , Imidazóis/toxicidade , Larva/efeitos dos fármacos , Contração Miocárdica/efeitos dos fármacos , Peixe-Zebra/embriologia , Acetilcolinesterase/metabolismo , Animais , Proteína Glial Fibrilar Ácida/biossíntese , Proteínas Hedgehog/biossíntese , Proteína Básica da Mielina/biossíntese , Natação , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/biossíntese
17.
Morfologiia ; 145(2): 7-11, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25282817

RESUMO

The aim of the study was to detect the neocortical columns in the S1 field on frontal sections of brain of albino rats using the method of immunohistochemistry and the antibodies against neuronal (synaptophysin, neurofilament) and gliocyte (glial fibrillary acidic protein--GFAP, myelin basic protein) proteins. The examination of the expression of the major neurospecific antigens revealed that on thin sections (4 micromin) a column could be identified due to accumulations of the astrocytes and neuronal processes--axons and dendrites. GFAP expression study also showed that cortical layer I usually contained multiple large astrocytes with branching processes, as well as numerous smaller processes with high intensity of expression. Synaptophysin content was high in all the layers of the cortex, but the most intense reaction was detected in the molecular layer, similarly with the intensity of GFAP reaction. The expression of myelin basic protein was detected in accordance with the radially extending myelinated processes of the neurons in the cortex.


Assuntos
Astrócitos , Axônios/metabolismo , Dendritos/metabolismo , Proteína Básica da Mielina/biossíntese , Córtex Somatossensorial , Sinaptofisina/biossíntese , Animais , Antígenos/biossíntese , Astrócitos/citologia , Astrócitos/metabolismo , Feminino , Masculino , Neocórtex/citologia , Neocórtex/metabolismo , Ratos , Córtex Somatossensorial/citologia , Córtex Somatossensorial/metabolismo
18.
Protein Expr Purif ; 101: 106-14, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24925644

RESUMO

During myelination in the central nervous system, proteins arising from the gene in the oligodendrocyte lineage (golli) participate in diverse events in signal transduction and gene regulation. One of the interacting partners of the Golli-isoform BG21 was discovered by yeast-2-hybrid means and was denoted the Golli-interacting-protein (GIP). In subsequent in vitro studies of recombinant murine GIP, it was not possible to produce a full-length version of recombinant murine rmGIP in functional form under native conditions, primarily because of solubility issues, necessitating the study of a hexahistidine-tagged, truncated form ΔN-rmGIP. This protein is an acidic phosphatase belonging to the family of RNA-polymerase-2, small-subunit, C-terminal phosphatases (SCP1), and studies of the human ortholog hSCP1 have also been performed on truncated forms. Here, a new SUMO-expression and purification protocol has been developed for the preparation of a functional, full-length mSCP1/GIP (our nomenclature henceforth), with no additional purification tags. Both full-length mSCP1/GIP and the truncated murine form (now denoted ΔN-rmSCP1/GIP) had similar melting temperatures, indicating that the integrity of the catalytic core per se was minimally affected by the N-terminus. Characterization of mSCP1/GIP activity with the artificial substrate p-NPP (p-nitrophenylphosphate) yielded kinetic parameters comparable to those of ΔN-rmSCP1/GIP and the truncated human ortholog ΔN-hSCP1. Similarly, mSCP1/GIP dephosphorylated a more natural CTD-peptide substrate (but not protein kinase C-phosphorylated BG21) with comparable kinetics to ΔN-hSCP1. The successful production of an active, full-length mSCP1/GIP will enable future evaluation of the functional role of its N-terminus in protein-protein interactions (e.g., BG21) that regulate its phosphatase activity.


Assuntos
Escherichia coli/metabolismo , Proteína Básica da Mielina/genética , Proteínas do Tecido Nervoso/genética , Proteínas Nucleares/genética , Proteínas Recombinantes/genética , Animais , Sistema Nervoso Central/metabolismo , Cromatografia de Afinidade , Escherichia coli/genética , Expressão Gênica , Regulação da Expressão Gênica , Camundongos , Proteína Básica da Mielina/biossíntese , Proteína Básica da Mielina/metabolismo , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/metabolismo , Nitrobenzenos/metabolismo , Proteínas Nucleares/biossíntese , Proteínas Nucleares/metabolismo , Fosforilação , Fosforilcolina/análogos & derivados , Fosforilcolina/metabolismo , Isoformas de Proteínas/genética , Proteínas Recombinantes/metabolismo , Transdução de Sinais/genética
19.
BMC Neurosci ; 15: 25, 2014 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-24524292

RESUMO

BACKGROUND: To explore the neuroprotective effect and optimize the therapeutic dose and time window of picroside II by orthogonal test and the expression of myelin basic protein (MBP) in cerebral ischemic injury in rats. Bilateral common carotid artery occlusion (BCCAO) was used to establish forebrain ischemia models. The successful rat models were grouped according to orthogonal experimental design and injected picroside II intraperitoneally at different ischemic time with different doses. Myelin sheath fast green staining(FGS) and transmission electron microscopy (TEM) were used to observe nerve fiber myelin; the expression of MBP was tested qualitatively and quantitatively by immunohistochemical assay (IHC) and Western blot (WB); Reverse transcription polymerase chain reaction (RT-PCR) was used to detect the transcription level of MBP mRNA. RESULTS: The protective effect of picroside II was presented by increasing the expression of MBP and decreasing demyelination after cerebral ischemic injury. The best therapeutic time window and dose was (1) ischemia 2.0 h with picroside II 10 mg/kg body weight according to the results of FGS, IHC and WB; (2) ischemia 1.5 h with picroside II 20 mg/kg according to the analysis of RT-PCR. CONCLUSION: Given the principle of the longest time window and the lowest therapeutic dose, the optimized therapeutic dose and time window should be injecting picroside II intraperitoneally with 10-20 mg/kg body weight at ischemia 1.5-2.0 h in cerebral ischemic injury.


Assuntos
Isquemia Encefálica/metabolismo , Isquemia Encefálica/prevenção & controle , Cinamatos/administração & dosagem , Regulação da Expressão Gênica/efeitos dos fármacos , Glucosídeos Iridoides/administração & dosagem , Proteína Básica da Mielina/biossíntese , Bainha de Mielina/patologia , Animais , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Injeções Intraperitoneais , Masculino , Bainha de Mielina/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Ratos , Ratos Wistar , Resultado do Tratamento
20.
Mol Ther ; 22(2): 440-450, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24247929

RESUMO

Neural stem cells (NSCs) have therapeutic potential in experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS); however, to date, their use has resulted in only limited clinical and pathological improvement. To enhance their therapeutic capacity, in the present study, we transduced bone marrow-derived NSCs (BM-NSCs) with neurotrophin 3 (NT-3), a potent neurotrophic factor that is both neuroprotective and immunomodulatory. We found that BM-NSCs transduced with NT-3 reduced central nervous system (CNS) inflammation and neurological deficits in ongoing EAE significantly more than conventional NSC therapy, and, in addition, had the following advantages: (i) enhanced BM-NSC proliferation and differentiation into oligodendrocytes and neurons, as well as inhibited differentiation into astrocytes, thus promoting remyelination and neuronal repopulation, and reducing astrogliosis; (ii) enhanced anti-inflammatory capacity of BM-NSCs, thus more effectively suppressing CNS inflammation and accelerating remyelination; (iii) the easy accessibility of BM-NSCs provides another advantage over brain-derived NSCs for MS therapy; and (iv) a novel Tet-on system we used enables efficient control of NT-3 expression. Thus, our study provides a novel approach to break the vicious inflammation-demyelination cycle, and could pave the way to an easily accessible and highly effective therapy for CNS inflammatory demyelination.


Assuntos
Imunomodulação , Bainha de Mielina/metabolismo , Células-Tronco Neurais/fisiologia , Neurotrofina 3/genética , Transdução Genética , Animais , Astrócitos/citologia , Astrócitos/metabolismo , Células da Medula Óssea/citologia , Células da Medula Óssea/patologia , Movimento Celular/genética , Proliferação de Células , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/metabolismo , Expressão Gênica , Genes Reporter , Fator Neurotrófico Derivado de Linhagem de Célula Glial/biossíntese , Inflamação/genética , Inflamação/imunologia , Inflamação/metabolismo , Interleucina-10/biossíntese , Camundongos , Mucolipidoses , Proteína Básica da Mielina/biossíntese , Células-Tronco Neurais/citologia , Neurônios/citologia , Neurônios/metabolismo , Neurotrofina 3/metabolismo , Oligodendroglia/citologia , Oligodendroglia/metabolismo
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