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1.
Int J Mol Sci ; 22(17)2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34502342

RESUMO

Our previous studies have demonstrated that specific peroxisome proliferator-activated receptor-γ (PPAR-γ) agonists play a fundamental role in oligodendrocyte progenitor (OP) differentiation, protecting them against oxidative and inflammatory damage. The antihypertensive drug Telmisartan (TLM) was shown to act as a PPAR-γ modulator. This study investigates the TLM effect on OP differentiation and validates its capability to restore damage in a pharmacological model of Niemann-Pick type C (NPC) disease through a PPAR-γ-mediated mechanism. For the first time in purified OPs, we demonstrate that TLM-induced PPAR-γ activation downregulates the type 1 angiotensin II receptor (AT1), the level of which naturally decreases during differentiation. Like other PPAR-γ agonists, we show that TLM promotes peroxisomal proliferation and promotes OP differentiation. Furthermore, TLM can offset the OP maturation arrest induced by a lysosomal cholesterol transport inhibitor (U18666A), which reproduces an NPC1-like phenotype. In the NPC1 model, TLM also reduces cholesterol accumulation within peroxisomal and lysosomal compartments and the contacts between lysosomes and peroxisomes, revealing that TLM can regulate intracellular cholesterol transport, crucial for myelin formation. Altogether, these data indicate a new potential use of TLM in hypomyelination pathologies such as NPC1, underlining the possible repositioning of the drug already used in other pathologies.


Assuntos
Anti-Hipertensivos/farmacologia , Diferenciação Celular , Colesterol/metabolismo , Oligodendroglia/efeitos dos fármacos , PPAR gama/metabolismo , Substâncias Protetoras/farmacologia , Telmisartan/farmacologia , Animais , Oligodendroglia/metabolismo , PPAR gama/genética , Ratos , Ratos Wistar
2.
Nat Commun ; 12(1): 5091, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34429415

RESUMO

Ten-eleven translocation (TET) proteins, the dioxygenase for DNA hydroxymethylation, are important players in nervous system development and diseases. However, their role in myelination and remyelination after injury remains elusive. Here, we identify a genome-wide and locus-specific DNA hydroxymethylation landscape shift during differentiation of oligodendrocyte-progenitor cells (OPC). Ablation of Tet1 results in stage-dependent defects in oligodendrocyte (OL) development and myelination in the mouse brain. The mice lacking Tet1 in the oligodendrocyte lineage develop behavioral deficiency. We also show that TET1 is required for remyelination in adulthood. Transcriptomic, genomic occupancy, and 5-hydroxymethylcytosine (5hmC) profiling reveal a critical TET1-regulated epigenetic program for oligodendrocyte differentiation that includes genes associated with myelination, cell division, and calcium transport. Tet1-deficient OPCs exhibit reduced calcium activity, increasing calcium activity rescues the differentiation defects in vitro. Deletion of a TET1-5hmC target gene, Itpr2, impairs the onset of OPC differentiation. Together, our results suggest that stage-specific TET1-mediated epigenetic programming and intracellular signaling are important for proper myelination and remyelination in mice.


Assuntos
Encéfalo/metabolismo , Proteínas de Ligação a DNA/metabolismo , DNA/metabolismo , Camundongos Mutantes Neurológicos/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Remielinização/fisiologia , 5-Metilcitosina/análogos & derivados , Animais , Ciclo Celular , Diferenciação Celular , Metilação de DNA , Proteínas de Ligação a DNA/genética , Genoma , Camundongos , Camundongos Knockout , Oligodendroglia/metabolismo , Organogênese , Proteínas Proto-Oncogênicas/genética
3.
Nat Commun ; 12(1): 5146, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34446732

RESUMO

The juvenile brain presents plasticity. Oligodendrocytes are the myelinating cells of the central nervous system and myelination can be adaptive. Plasticity decreases from juvenile to adulthood. The mechanisms involving oligodendrocytes underlying plasticity are unclear. Here, we show Na+-K+-Cl- co-transporter 1 (NKCC1), highly expressed in the juvenile mouse brain, regulates the oligodendrocyte activity from juvenile to adulthood in mice, as shown by optogenetic manipulation of oligodendrocytes. The reduced neuronal activity in adults was restored by Nkcc1 overexpression in oligodendrocytes. Moreover, in adult mice overexpressing Nkcc1, long-term potentiation and learning were facilitated compared to age-matched controls. These findings demonstrate that NKCC1 plays a regulatory role in the age-dependent activity of oligodendrocytes, furthermore inducing activation of NKCC1 in oligodendrocytes can restore neuronal plasticity in the adult mouse brain.


Assuntos
Axônios/metabolismo , Encéfalo/fisiologia , Plasticidade Neuronal , Oligodendroglia/metabolismo , Membro 2 da Família 12 de Carreador de Soluto/metabolismo , Animais , Encéfalo/citologia , Feminino , Aprendizagem , Masculino , Camundongos , Neurônios/metabolismo , Membro 2 da Família 12 de Carreador de Soluto/genética
4.
Int J Mol Sci ; 22(15)2021 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-34360675

RESUMO

In recent decades, interest in natural compounds has increased exponentially due to their numerous beneficial properties in the treatment of various acute and chronic diseases. A group of plant derivatives with great scientific interest is terpenic compounds. Among the plants richest in terpenes, the genus Ferula L. is one of the most representative, and ferutinin, the most common sesquiterpene, is extracted from the leaves, rhizome, and roots of this plant. As reported in the scientific literature, ferutinin possesses antioxidant and anti-inflammatory properties, as well as valuable estrogenic properties. Neurodegenerative and demyelinating diseases are devastating conditions for which a definite cure has not yet been established. The mechanisms involved in these diseases are still poorly understood, and oxidative stress is considered to be both a key modulator and a common denominator. In the proposed experimental system, co-cultured human neurons (SH-SY5Y) and human oligodendrocytes (MO3.13) were treated with the pro-inflammatory agent lipopolysaccharide at a concentration of 1 µg/mL for 24 h or pretreated with ferutinin (33 nM) for 24 h and subsequently exposed to lipopolysaccharide 1 µg/mL for 24 h. Further studies would, however, be needed to establish whether this natural compound can be used as a support strategy in pathologies characterized by progressive inflammation and oxidative stress phenomena.


Assuntos
Benzoatos/farmacologia , Cicloeptanos/farmacologia , Inflamação/tratamento farmacológico , Lipopolissacarídeos/toxicidade , Neurônios/efeitos dos fármacos , Oligodendroglia/efeitos dos fármacos , Estresse Oxidativo , Sesquiterpenos/farmacologia , Compostos Bicíclicos com Pontes/farmacologia , Linhagem Celular , Técnicas de Cocultura , Escherichia coli , Humanos , Inflamação/induzido quimicamente , Neurônios/metabolismo , Neurônios/patologia , Oligodendroglia/metabolismo , Oligodendroglia/patologia , Substâncias Protetoras/farmacologia
5.
ACS Chem Biol ; 16(7): 1288-1297, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34232635

RESUMO

Inducing the formation of new oligodendrocytes from oligodendrocyte progenitor cells (OPCs) represents a potential approach to repairing the loss of myelin observed in multiple sclerosis and other diseases. Recently, we demonstrated that accumulation of specific cholesterol precursors, 8,9-unsaturated sterols, is a dominant mechanism by which dozens of small molecules enhance oligodendrocyte formation. Here, we evaluated a library of 56 sterols and steroids to evaluate whether other classes of bioactive sterol derivatives may also influence mouse oligodendrocyte precursor cell (OPC) differentiation or survival. From this library, we identified U-73343 as a potent enhancer of oligodendrocyte formation that induces 8,9-unsaturated sterol accumulation by inhibition of the cholesterol biosynthesis enzyme sterol 14-reductase. In contrast, we found that mouse OPCs are remarkably vulnerable to treatment with the glycosterol OSW-1, an oxysterol-binding protein (OSBP) modulator that induces Golgi stress and OPC death in the low picomolar range. A subsequent small-molecule suppressor screen identified mTOR signaling as a key effector pathway mediating OSW-1's cytotoxic effects in mouse OPCs. Finally, evaluation of a panel of ER and Golgi stress-inducing small molecules revealed that mouse OPCs are highly sensitive to these perturbations, more so than closely related neural progenitor cells. Together, these studies highlight the wide-ranging influence of sterols and steroids on OPC cell fate, with 8,9-unsaturated sterols positively enhancing differentiation to oligodendrocytes and OSW-1 able to induce lethal Golgi stress with remarkable potency.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Células Precursoras de Oligodendrócitos/efeitos dos fármacos , Esteróis/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Colestenonas/farmacologia , Colestenonas/toxicidade , Avaliação Pré-Clínica de Medicamentos , Retículo Endoplasmático/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Estrenos/farmacologia , Complexo de Golgi/efeitos dos fármacos , Células HeLa , Humanos , Camundongos , Células Precursoras de Oligodendrócitos/metabolismo , Oligodendroglia/metabolismo , Pirrolidinonas/farmacologia , Saponinas/farmacologia , Saponinas/toxicidade , Bibliotecas de Moléculas Pequenas/farmacologia , Bibliotecas de Moléculas Pequenas/toxicidade , Esteróis/toxicidade
6.
Commun Biol ; 4(1): 870, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34267322

RESUMO

The role of oligodendrocyte lineage cells, the largest glial population in the adult central nervous system (CNS), in the pathogenesis of Alzheimer's disease (AD) remains elusive. Here, we developed a culture method for adult oligodendrocyte progenitor cells (aOPCs). Fibroblast growth factor 2 (FGF2) promotes survival and proliferation of NG2+ aOPCs in a serum-free defined medium; a subpopulation (~5%) of plexin-B3+ aOPCs was also found. FGF2 withdrawal decreased NG2+, but increased plexin-B3+ aOPCs and Aß1-42 secretion. Plexin-B3+ aOPCs were distributed throughout the adult rat brain, although less densely than NG2+ aOPCs. Spreading depolarization induced delayed cortical plexin-B3+ aOPC gliosis in the ipsilateral remote cortex. Furthermore, extracellular Aß1-42 accumulation was occasionally found around plexin-B3+ aOPCs near the lesions. In AD brains, virtually all cortical SPs were immunostained for plexin-B3, and plexin-B3 levels increased significantly in the Sarkosyl-soluble fractions. These findings suggest that plexin-B3+ aOPCs may play essential roles in AD pathogenesis, as natural Aß-secreting cells.


Assuntos
Doença de Alzheimer/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Células Precursoras de Oligodendrócitos/metabolismo , Oligodendroglia/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Animais , Antígenos/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Células Cultivadas , Feminino , Humanos , Masculino , Moléculas de Adesão de Célula Nervosa/metabolismo , Células Precursoras de Oligodendrócitos/citologia , Oligodendroglia/citologia , Fragmentos de Peptídeos/metabolismo , Proteoglicanas/metabolismo , Ratos Sprague-Dawley
7.
Methods Mol Biol ; 2352: 149-170, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34324186

RESUMO

Oligodendrocytes are the main glial cell type in the central nervous system supporting the axonal part of neurons via myelin and lactate delivery. Both the conductive myelin formation and the energy support via lactate can be affected in diseases, such as multiple sclerosis and amyotrophic lateral sclerosis, respectively. Therefore, human disease modeling is needed to gain more mechanistic insights to drive drug discovery research. Here, patient-derived induced pluripotent stem cells (iPSCs) serve as a necessary tool providing an infinite cell source for patient-specific disease modeling, which allows investigation of oligodendrocyte involvement in human disease.Small molecule-based differentiation protocols to generate oligodendrocytes from pluripotent stem cells can last more than 90 days. Here, we provide a transcription factor-based, fast and efficient protocol for generating O4+ oligodendrocytes in just 20-24 days. After a neural induction phase of 8-12 days, SOX10 is overexpressed either with the use of lentiviral vectors or via engineered iPSCs, which inducibly overexpress SOX10 after doxycycline addition. Using this last method, a pure O4+ cell population is achieved after keeping the SOX10-overexpressing neural stem cells in culture for an additional 10 days. Furthermore, these O4+ cells can be co-cultured with iPSC-derived cortical neurons in 384-well format, allowing pro-myelinating drug screens. In conclusion, we provide a fast and efficient oligodendrocyte differentiation protocol allowing both in vitro human disease modeling and a high-throughput co-culture system for drug discovery.


Assuntos
Diferenciação Celular/genética , Expressão Gênica , Oligodendroglia/citologia , Oligodendroglia/metabolismo , Fatores de Transcrição SOXE/genética , Fatores de Transcrição/genética , Técnicas de Cultura de Células , Células Cultivadas , Clonagem Molecular , Ordem dos Genes , Vetores Genéticos/administração & dosagem , Vetores Genéticos/biossíntese , Vetores Genéticos/genética , Humanos , Separação Imunomagnética , Lentivirus/genética , Neurogênese
8.
Eur J Med Genet ; 64(9): 104282, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34284163

RESUMO

The Forkhead transcription factor FOXG1 is a prerequisite for telencephalon development in mammals and is an essential factor controlling expansion of the dorsal telencephalon by promoting neuron and interneuron production. Heterozygous FOXG1 gene mutations cause FOXG1 syndrome characterized by severe intellectual disability, motor delay, dyskinetic movements and epilepsy. Neuroimaging studies in patients disclose constant features including microcephaly, corpus callosum dysgenesis and delayed myelination. Currently, investigative research on the underlying pathophysiology relies on mouse models only and indicates that de-repression of FOXG1 target genes may cause premature neuronal differentiation at the expense of the progenitor pool, patterning and migration defects with impaired formation of cortico-cortical projections. It remains an open question to which extent this recapitulates the neurodevelopmental pathophysiology in FOXG1-haploinsufficient patients. To close this gap, we performed neuropathological analyses in two foetal cases with FOXG1 premature stop codon mutations interrupted during the third trimester of the pregnancy for microcephaly and corpus callosum dysgenesis. In these foetuses, we observed cortical lamination defects and decreased neuronal density mainly affecting layers II, III and V that normally give rise to cortico-cortical and inter-hemispheric axonal projections. GABAergic interneurons were also reduced in number in the cortical plate and persisting germinative zones. Additionally, we observed more numerous PDGFRα-positive oligodendrocyte precursor cells and fewer Olig2-positive pre-oligodendrocytes compared to age-matched control brains, arguing for delayed production and differentiation of oligodendrocyte lineage leading to delayed myelination. These findings provide key insights into the human pathophysiology of FOXG1 syndrome.


Assuntos
Agenesia do Corpo Caloso/genética , Axônios/patologia , Fatores de Transcrição Forkhead/genética , Microcefalia/genética , Proteínas do Tecido Nervoso/genética , Transtornos do Neurodesenvolvimento/genética , Neurogênese , Oligodendroglia/patologia , Feto Abortado/metabolismo , Feto Abortado/patologia , Adulto , Agenesia do Corpo Caloso/patologia , Axônios/metabolismo , Encéfalo/embriologia , Encéfalo/metabolismo , Encéfalo/patologia , Códon sem Sentido , Feminino , Fatores de Transcrição Forkhead/metabolismo , Neurônios GABAérgicos/metabolismo , Neurônios GABAérgicos/patologia , Humanos , Interneurônios/metabolismo , Interneurônios/patologia , Microcefalia/patologia , Bainha de Mielina/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Transtornos do Neurodesenvolvimento/patologia , Oligodendroglia/metabolismo , Linhagem , Gravidez , Síndrome
9.
Life Sci ; 282: 119812, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34265362

RESUMO

AIMS: Among all the treatments for Multiple Sclerosis, stem cell transplantation, such as ADSCs, has attracted a great deal of scientific attention. On the other hand, Edaravone, as an antioxidant component, in combination with stem cells, could increase the survival and differentiation potential of stem cells. MAIN METHODS: 42 rats were divided into: Control, Cuprizone (CPZ), Sham, Edaravone (Ed), hADSCs, and Ed/hADSCs groups. Following induction of cuprizone, induced MS model, behavioral tests were designed to evaluate motor function during. Luxal fast blue staining was done to measure the level of demyelination and remyelination. Immunofluorescent staining was used to evaluate the amount of MBP, OLIG2, and MOG proteins. The mRNA levels of human MBP, MOG, and OLIG2 and rat Mbp, Mog, and Olig2 were determined via RT-PCR. KEY FINDINGS: Flow cytometry analysis exhibited that the extracted cells were positive for CD73 (93.8 ± 3%) and CD105 (91.6 ± 3%), yet negative for CD45 (2.06 ± 0.5%). Behavioral tests, unveiled a significant improvement in the Ed (P < 0.001), hADSCs (P < 0.001), and Ed/hADSCs (P < 0.001) groups compared to the others. In the Ed/hADSCs group, the myelin density was significantly higher than that in the Ed treated and hADSCs treated groups (P < 0.01). Edaravone and hADSCs increased the expression of Mbp, Mog, and Olig2 genes in the cuprizone rat models. Moreover, significant differences were seen between the Ed treated and hADSCs treated groups and the Ed/hADSCs group (P < 0.05 for Mbp and Olig2 and P < 0.01 for Mog). SIGNIFICANCE: Edaravone in combination with hADSCs reduced demyelination and increased oligodendrogenesis in the cuprizone rat models.


Assuntos
Tecido Adiposo/metabolismo , Diferenciação Celular/efeitos dos fármacos , Edaravone/farmacologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/metabolismo , Esclerose Múltipla , Oligodendroglia/metabolismo , Animais , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Xenoenxertos , Humanos , Esclerose Múltipla/metabolismo , Esclerose Múltipla/terapia , Ratos
10.
Int J Mol Sci ; 22(13)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206635

RESUMO

White matter tract (WMT) degeneration has been reported to occur following a stroke, and it is associated with post-stroke functional disturbances. White matter pathology has been suggested to be an independent predictor of post-stroke recovery. However, the factors that influence WMT remodeling are poorly understood. Cortisol is a steroid hormone released in response to prolonged stress, and elevated levels of cortisol have been reported to interfere with brain recovery. The objective of this study was to investigate the influence of corticosterone (CORT; the rodent equivalent of cortisol) on WMT structure post-stroke. Photothrombotic stroke (or sham surgery) was induced in 8-week-old male C57BL/6 mice. At 72 h, mice were exposed to standard drinking water ± CORT (100 µg/mL). After two weeks of CORT administration, mice were euthanised and brain tissue collected for histological and biochemical analysis of WMT (particularly the corpus callosum and corticospinal tract). CORT administration was associated with increased tissue loss within the ipsilateral hemisphere, and modest and inconsistent WMT reorganization. Further, a structural and molecular analysis of the WMT components suggested that CORT exerted effects over axons and glial cells. Our findings highlight that CORT at stress-like levels can moderately influence the reorganization and microstructure of WMT post-stroke.


Assuntos
Corticosterona/administração & dosagem , Gliose/metabolismo , Gliose/patologia , Vias Neurais/efeitos dos fármacos , Acidente Vascular Cerebral/metabolismo , Substância Branca/efeitos dos fármacos , Substância Branca/fisiologia , Animais , Axônios/metabolismo , Corpo Caloso/efeitos dos fármacos , Corpo Caloso/metabolismo , Corpo Caloso/patologia , Modelos Animais de Doenças , Progressão da Doença , Suscetibilidade a Doenças , Gliose/tratamento farmacológico , Gliose/etiologia , Imuno-Histoquímica , Masculino , Camundongos , Bainha de Mielina/efeitos dos fármacos , Bainha de Mielina/metabolismo , Oligodendroglia/efeitos dos fármacos , Oligodendroglia/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/patologia
11.
Nat Commun ; 12(1): 3359, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099715

RESUMO

The mechanisms regulating myelin repair in the adult central nervous system (CNS) are unclear. Here, we identify DNA hydroxymethylation, catalyzed by the Ten-Eleven-Translocation (TET) enzyme TET1, as necessary for myelin repair in young adults and defective in old mice. Constitutive and inducible oligodendrocyte lineage-specific ablation of Tet1 (but not of Tet2), recapitulate this age-related decline in repair of demyelinated lesions. DNA hydroxymethylation and transcriptomic analyses identify TET1-target in adult oligodendrocytes, as genes regulating neuro-glial communication, including the solute carrier (Slc) gene family. Among them, we show that the expression levels of the Na+/K+/Cl- transporter, SLC12A2, are higher in Tet1 overexpressing cells and lower in old or Tet1 knockout. Both aged mice and Tet1 mutants also present inefficient myelin repair and axo-myelinic swellings. Zebrafish mutants for slc12a2b also display swellings of CNS myelinated axons. Our findings suggest that TET1 is required for adult myelin repair and regulation of the axon-myelin interface.


Assuntos
Metilação de DNA , Proteínas de Ligação a DNA/genética , Perfilação da Expressão Gênica/métodos , Bainha de Mielina/genética , Proteínas Proto-Oncogênicas/genética , Remielinização/genética , Animais , Animais Geneticamente Modificados , Células Cultivadas , Proteínas de Ligação a DNA/metabolismo , Camundongos Knockout , Camundongos Transgênicos , Mutação , Bainha de Mielina/metabolismo , Oligodendroglia/citologia , Oligodendroglia/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , RNA-Seq/métodos , Membro 2 da Família 12 de Carreador de Soluto/genética , Membro 2 da Família 12 de Carreador de Soluto/metabolismo , Peixe-Zebra/genética
12.
Dev Cell ; 56(13): 1821-1832, 2021 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-34192527

RESUMO

Developmental myelination is a protracted process that extends well into postnatal life. Cell-intrinsic mechanisms operate in myelin-forming oligodendrocytes, as well as microenvironmental interactions that guide and modulate every aspect of myelination, from oligodendrocyte precursor cell migration to oligodendrocyte differentiation and the formation of stable myelin internodes. During development and throughout adult life, neuron-oligodendroglial interactions shape activity and experience-dependent myelin adaptations to fine-tune neural circuit dynamics and promote healthy neurological function.


Assuntos
Microambiente Celular/genética , Bainha de Mielina/genética , Neurônios/metabolismo , Oligodendroglia/metabolismo , Diferenciação Celular/genética , Movimento Celular/genética , Humanos
13.
Neurosci Bull ; 37(9): 1314-1324, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34091810

RESUMO

The exacerbation of progressive multiple sclerosis (MS) is closely associated with obstruction of the differentiation of oligodendrocyte progenitor cells (OPCs). To discover novel therapeutic compounds for enhancing remyelination by endogenous OPCs, we screened for myelin basic protein expression using cultured rat OPCs and a library of small-molecule compounds. One of the most effective drugs was pinocembrin, which remarkably promoted OPC differentiation and maturation without affecting cell proliferation and survival. Based on these in vitro effects, we further assessed the therapeutic effects of pinocembrin in animal models of demyelinating diseases. We demonstrated that pinocembrin significantly ameliorated the progression of experimental autoimmune encephalomyelitis (EAE) and enhanced the repair of demyelination in lysolectin-induced lesions. Further studies indicated that pinocembrin increased the phosphorylation level of mammalian target of rapamycin (mTOR). Taken together, our results demonstrated that pinocembrin promotes OPC differentiation and remyelination through the phosphorylated mTOR pathway, and suggest a novel therapeutic prospect for this natural flavonoid product in treating demyelinating diseases.


Assuntos
Remielinização , Animais , Diferenciação Celular , Flavanonas , Camundongos , Camundongos Endogâmicos C57BL , Bainha de Mielina/metabolismo , Oligodendroglia/metabolismo , Ratos , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
14.
Int J Mol Sci ; 22(10)2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-34067536

RESUMO

Several virus-induced models were used to study the underlying mechanisms of multiple sclerosis (MS). The infection of susceptible mice with Theiler's murine encephalomyelitis virus (TMEV) establishes persistent viral infections and induces chronic inflammatory demyelinating disease. In this review, the innate and adaptive immune responses to TMEV are discussed to better understand the pathogenic mechanisms of viral infections. Professional (dendritic cells (DCs), macrophages, and B cells) and non-professional (microglia, astrocytes, and oligodendrocytes) antigen-presenting cells (APCs) are the major cell populations permissive to viral infection and involved in cytokine production. The levels of viral loads and cytokine production in the APCs correspond to the degrees of susceptibility of the mice to the TMEV-induced demyelinating diseases. TMEV infection leads to the activation of cytokine production via TLRs and MDA-5 coupled with NF-κB activation, which is required for TMEV replication. These activation signals further amplify the cytokine production and viral loads, promote the differentiation of pathogenic Th17 responses, and prevent cellular apoptosis, enabling viral persistence. Among the many chemokines and cytokines induced after viral infection, IFN α/ß plays an essential role in the downstream expression of costimulatory molecules in APCs. The excessive levels of cytokine production after viral infection facilitate the pathogenesis of TMEV-induced demyelinating disease. In particular, IL-6 and IL-1ß play critical roles in the development of pathogenic Th17 responses to viral antigens and autoantigens. These cytokines, together with TLR2, may preferentially generate deficient FoxP3+CD25- regulatory cells converting to Th17. These cytokines also inhibit the apoptosis of TMEV-infected cells and cytolytic function of CD8+ T lymphocytes (CTLs) and prolong the survival of B cells reactive to viral and self-antigens, which preferentially stimulate Th17 responses.


Assuntos
Doenças Desmielinizantes/imunologia , Esclerose Múltipla/imunologia , Theilovirus/fisiologia , Imunidade Adaptativa/imunologia , Animais , Células Apresentadoras de Antígenos/metabolismo , Astrócitos/metabolismo , Infecções por Cardiovirus/imunologia , Infecções por Cardiovirus/metabolismo , Infecções por Cardiovirus/virologia , Citocinas , Doenças Desmielinizantes/patologia , Modelos Animais de Doenças , Humanos , Imunidade Inata/imunologia , Camundongos , Microglia/metabolismo , Esclerose Múltipla/metabolismo , Oligodendroglia/metabolismo , Transdução de Sinais/imunologia , Theilovirus/patogenicidade
15.
Int J Mol Sci ; 22(10)2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-34063504

RESUMO

Protein kinase C (PKC) activation induces cellular reprogramming and differentiation in various cell models. Although many effectors of PKC physiological actions have been elucidated, the molecular mechanisms regulating oligodendrocyte differentiation after PKC activation are still unclear. Here, we applied a liquid chromatography-mass spectrometry (LC-MS/MS) approach to provide a comprehensive analysis of the proteome expression changes in the MO3.13 oligodendroglial cell line after PKC activation. Our findings suggest that multiple networks that communicate and coordinate with each other may finally determine the fate of MO3.13 cells, thus identifying a modular and functional biological structure. In this work, we provide a detailed description of these networks and their participating components and interactions. Such assembly allows perturbing each module, thus describing its physiological significance in the differentiation program. We applied this approach by targeting the Rho-associated protein kinase (ROCK) in PKC-activated cells. Overall, our findings provide a resource for elucidating the PKC-mediated network modules that contribute to a more robust knowledge of the molecular dynamics leading to this cell fate transition.


Assuntos
Diferenciação Celular/fisiologia , Oligodendroglia/citologia , Oligodendroglia/metabolismo , Proteína Quinase C/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Humanos , Espectrometria de Massas/métodos , Oligodendroglia/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Acetato de Tetradecanoilforbol/farmacologia , Quinases Associadas a rho/metabolismo
16.
PLoS One ; 16(5): e0250486, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33975330

RESUMO

Research into the epigenome is of growing importance as a loss of epigenetic control has been implicated in the development of neurodegenerative diseases. Previous studies have implicated aberrant DNA and histone methylation in multiple sclerosis (MS) disease pathogenesis. We have previously reported that the methyl donor betaine is depleted in MS and is linked to changes in histone H3 trimethylation (H3K4me3) in neurons. We have also shown that betaine increases histone methyltransferase activity by activating chromatin bound betaine homocysteine S-methyltransferase (BHMT). Here, we investigated the role of the BHMT-betaine methylation pathway in oligodendrocytes. Immunocytochemistry in the human MO3.13 cell line, primary rat oligodendrocytes, and tissue from MS postmortem brain confirmed the presence of the BHMT enzyme in the nucleus in oligodendrocytes. BHMT expression is increased 2-fold following oxidative insult, and qRT-PCR demonstrated that betaine can promote an increase in expression of oligodendrocyte maturation genes SOX10 and NKX-2.2 under oxidative conditions. Chromatin fractionation provided evidence of a direct interaction of BHMT on chromatin and co-IP analysis indicates an interaction between BHMT and DNMT3a. Our data show that both histone and DNA methyltransferase activity are increased following betaine administration. Betaine effects were shown to be dependent on BHMT expression following siRNA knockdown of BHMT. This is the first report of BHMT expression in oligodendrocytes and suggests that betaine acts through BHMT to modulate histone and DNA methyltransferase activity on chromatin. These data suggest that methyl donor availability can impact epigenetic changes and maturation in oligodendrocytes.


Assuntos
Betaína-Homocisteína S-Metiltransferase/metabolismo , Betaína/metabolismo , Esclerose Múltipla/patologia , Oligodendroglia/efeitos dos fármacos , Animais , Betaína/farmacologia , Betaína-Homocisteína S-Metiltransferase/antagonistas & inibidores , Betaína-Homocisteína S-Metiltransferase/genética , Encéfalo/metabolismo , Encéfalo/patologia , Células Cultivadas , Cromatina/metabolismo , DNA (Citosina-5-)-Metiltransferases/metabolismo , Epigênese Genética , Expressão Gênica/efeitos dos fármacos , Histonas/metabolismo , Humanos , Metionina/metabolismo , Metilação , Esclerose Múltipla/genética , Nitroprussiato/farmacologia , Oligodendroglia/citologia , Oligodendroglia/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Ratos , Fatores de Transcrição SOXE/metabolismo
17.
J Cell Mol Med ; 25(11): 5150-5163, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33939286

RESUMO

Accordingly to its known function in corticospinal tract (CST) developmental growth, previous reports have shown an inhibitory role of Wnt5a in CST regeneration after spinal cord injury (SCI). Interestingly, it has been subsequently demonstrated that Wnt5a also modulates the developmental growth of non-CST axons and that different Wnt5a receptors are expressed in neurons, oligodendrocytes, NG2+ glial precursors and reactive microglia/macrophages and astrocytes after SCI. However, the role of Wnt5a in the response of these cell types, in the regeneration of non-CST axons and in functional recovery after SCI is currently unknown. To evaluate this, rats were subjected to spinal cord contusion and injected with a lentiviral vector generated to overexpress Wnt5a. Histological analyses were performed in spinal cord sections processed for the visualization of myelin, oligodendrocytes, neurons, microglia/macrophages, astrocytes, NG2+ glial precursors and serotonergic axons. Motor and bladder function recovery were also assessed. Further advancing our knowledge on the role of Wnt5a in SCI, we found that, besides its previously reported functions, Wnt5a overexpression elicits a reduction on neuronal cell density, the accumulation of NG2+ glial precursors and the descending serotonergic innervation in the affected areas, along with impairment of motor and bladder function recovery after SCI.


Assuntos
Bainha de Mielina/patologia , Regeneração Nervosa , Neurônios/patologia , Oligodendroglia/patologia , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal/fisiopatologia , Proteína Wnt-5a/metabolismo , Animais , Feminino , Bainha de Mielina/metabolismo , Neurônios/metabolismo , Oligodendroglia/metabolismo , Ratos , Ratos Wistar , Proteína Wnt-5a/genética
18.
Exp Cell Res ; 405(1): 112654, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34044015

RESUMO

Oligodendroglial cells (oligodendrocytes) differentiate to form the myelin that wraps neuronal axons in the central nervous system (CNS). This myelin sheath supports the propagation of saltatory conduction and protects axons from physical stresses. When oligodendrocytes do not normally differentiate to myelinate axons, their key functions as oligodendrocytes in the CNS are severely impaired. The molecular mechanics that control differentiation still remain to be clarified. Arf6 belongs to the small GTPase family and is known to be a positive regulator of oligodendrocyte differentiation. Here, we show that the phospholipase D (PLD) and phosphatidylinositol-4-phosphate 5-kinase 1 (PIP5K1) molecules, the major effectors of Arf6, are involved in the regulation of oligodendrocyte differentiation. Knockdown of PLD1 or PIP5K type 1γ (PIP5K1C) by their respective specific siRNAs in mouse oligodendroglial FBD-102b cells inhibited morphological differentiation into structures bearing myelin-like processes; this finding is consistent with the concurrent changes in expression of differentiation and myelin marker proteins. Treatment with VU0155069 or UNC3230, specific inhibitors of PLD and PIP5K1, respectively, blunted morphological differentiation and decreased expression of myelin and differentiation marker proteins. Similar results have been obtained in studies using primary oligodendrocytes. These results suggest that the major Arf6 effector molecules PLD and PIP5K1 are among the molecules involved in the regulation of morphological differentiation in oligodendrocytes prior to myelination.


Assuntos
Encéfalo/citologia , Diferenciação Celular , Neurogênese , Oligodendroglia/citologia , Fosfolipase D/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Animais , Encéfalo/metabolismo , Células Cultivadas , Camundongos , Neurônios/citologia , Neurônios/metabolismo , Oligodendroglia/metabolismo
19.
Cell Prolif ; 54(7): e13027, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33988263

RESUMO

OBJECTIVES: The area of the subventricular zone (SVZ) in the adult brain exhibits the highest number of proliferative cells, which, together with the olfactory bulb (OB), maintains constant brain plasticity through the generation, migration and integration of newly born neurons. Despite Tau and its malfunction is increasingly related to deficits of adult hippocampal neurogenesis and brain plasticity under pathological conditions [e.g. in Alzheimer's disease (AD)], it remains unknown whether Tau plays a role in the neurogenic process of the SVZ and OB system under conditions of chronic stress, a well-known sculptor of brain and risk factor for AD. MATERIALS AND METHODS: Different types of newly born cells in SVZ and OB were analysed in animals that lack Tau gene (Tau-KO) and their wild-type littermates (WT) under control or chronic stress conditions. RESULTS: We demonstrate that chronic stress reduced the number of proliferating cells and neuroblasts in the SVZ leading to decreased number of newborn neurons in the OB of adult WT, but not Tau-KO, mice. Interestingly, while stress-evoked changes were not detected in OB granular cell layer, Tau-KO exhibited increased number of mature neurons in this layer indicating altered neuronal migration due to Tau loss. CONCLUSIONS: Our findings suggest the critical involvement of Tau in the neurogenesis suppression of SVZ and OB neurogenic niche under stressful conditions highlighting the role of Tau protein as an essential regulator of stress-driven plasticity deficits.


Assuntos
Ventrículos Laterais/metabolismo , Bulbo Olfatório/metabolismo , Estresse Fisiológico , Proteínas tau/metabolismo , Animais , Comportamento Animal , Proliferação de Células , Sobrevivência Celular , Ventrículos Laterais/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Neurogênese , Bulbo Olfatório/patologia , Oligodendroglia/citologia , Oligodendroglia/metabolismo , Proteínas tau/genética
20.
J Med Chem ; 64(9): 5667-5688, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33949859

RESUMO

Multiple sclerosis (MS) is an autoimmune demyelinating disease of the central nervous system (CNS) that causes severe motor, sensory, and cognitive impairments. Kallikrein-related peptidase (KLK)6 is the most abundant serine protease secreted in the CNS, mainly by oligodendrocytes, the myelin-producing cells of the CNS, and KLK6 is assumed to be a robust biomarker of MS, since it is highly increased in the cerebrospinal fluid (CSF) of MS patients. Here, we report the design and biological evaluation of KLK6's low-molecular-weight inhibitors, para-aminobenzyl derivatives. Interestingly, selected hit compounds were selective of the KLK6 proteolytic network encompassing KLK1 and plasmin that also participate in the development of MS physiopathology. Moreover, hits were found noncytotoxic on primary cultures of murine neurons and oligodendrocyte precursor cells (OPCs). Among them, two compounds (32 and 42) were shown to promote the differentiation of OPCs into mature oligodendrocytes in vitro constituting thus emerging leads for the development of regenerative therapies.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Calicreínas/antagonistas & inibidores , Inibidores de Serino Proteinase/farmacologia , Animais , Derivados de Benzeno/química , Derivados de Benzeno/metabolismo , Derivados de Benzeno/farmacologia , Sítios de Ligação , Domínio Catalítico , Células Cultivadas , Desenho de Fármacos , Fibrinolisina/antagonistas & inibidores , Fibrinolisina/metabolismo , Humanos , Calicreínas/metabolismo , Cinética , Camundongos , Simulação de Acoplamento Molecular , Esclerose Múltipla/metabolismo , Esclerose Múltipla/patologia , Neurônios/citologia , Neurônios/metabolismo , Oligodendroglia/citologia , Oligodendroglia/metabolismo , Inibidores de Serino Proteinase/química , Inibidores de Serino Proteinase/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Relação Estrutura-Atividade
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