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1.
Cell Mol Life Sci ; 2021 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-34482420

RESUMO

The differentiation of oligodendrocyte precursor cells (OPCs) into myelinating oligodendrocytes is the prerequisite for remyelination in demyelinated disorders such as multiple sclerosis (MS). Epigenetic mechanisms, such as DNA methylation, have been suggested to control the intricate network of transcription factors involved in OPC differentiation. Yet, the exact mechanism remains undisclosed. Here, we are the first to identify the DNA-binding protein inhibitors, Id2 and Id4, as targets of DNA methylation during OPC differentiation. Using state-of-the-art epigenetic editing via CRISPR/dCas9-DNMT3a, we confirm that targeted methylation of Id2/Id4 drives OPC differentiation. Moreover, we show that in the pathological context of MS, methylation and gene expression levels of both ID2 and ID4 are altered compared to control human brain samples. We conclude that DNA methylation is crucial to suppress ID2 and ID4 during OPC differentiation, a process that appears to be dysregulated during MS. Our data do not only reveal new insights into oligodendrocyte biology, but could also lead to a better understanding of CNS myelin disorders.

2.
Lancet Gastroenterol Hepatol ; 6(10): 784-792, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34358486

RESUMO

BACKGROUND: Current treatments for functional dyspepsia have limited efficacy or present safety issues. We aimed to assess spore-forming probiotics in functional dyspepsia as monotherapy or add-on therapy to long-term treatment with proton-pump inhibitors. METHODS: In this single-centre, randomised, double-blind, placebo-controlled pilot trial that took place at University Hospitals Leuven (Leuven, Belgium), adult patients (≥18 years) with functional dyspepsia (as defined by Rome IV criteria, on proton-pump inhibitors or off proton-pump inhibitors) were randomly assigned (1:1) via computer-generated blocked lists, stratified by proton-pump inhibitor status, to receive 8 weeks of treatment with probiotics (Bacillus coagulans MY01 and Bacillus subtilis MY02, 2·5 × 109 colony-forming units per capsule) or placebo consumed twice per day, followed by an open-label extension phase of 8 weeks. Individuals with a history of abdominal surgery, diabetes, coeliac or inflammatory bowel disease, active psychiatric conditions, and use of immunosuppressant drugs, antibiotics, or probiotics in the past 3 months were excluded. All patients and on-site study personnel were masked to treatment allocation in the first 8 weeks. Symptoms, immune activation, and faecal microbiota were assessed and recorded. The primary endpoint was a decrease of at least 0·7 in the postprandial distress syndrome (PDS) score of the Leuven Postprandial Distress Scale in patients with a baseline PDS score of 1 or greater (at least mild symptoms), assessed in the intention-to-treat population. This study is registered with ClinicalTrials.gov, NCT04030780. FINDINGS: Between June 3, 2019, and March 11, 2020, of 93 individuals assessed for eligibility, we included 68 patients with functional dyspepsia (51 [75%] women, mean age 40·1 years [SD 14·4], 34 [50%] on proton-pump inhibitors). We randomly assigned 32 participants to probiotics and 36 to placebo. The proportion of clinical responders was higher with probiotics (12 [48%] of 25) than placebo (six [20%] of 30; relative risk 1·95 [95% CI 1·07-4·11]; p=0·028). The number of patients with adverse events was similar with probiotics (five [16%] of 32) and placebo (12 [33%] of 36). Two serious adverse events occurring during the open-label phase (appendicitis and syncope in two separate patients) were assessed as unlikely to be related to the study product. INTERPRETATION: In this exploratory study, B coagulans MY01 and B subtilis MY02 were efficacious and safe in the treatment of functional dyspepsia. Participants had potentially beneficial immune and microbial changes, which could provide insights into possible underlying mechanisms as future predictors or treatment targets. FUNDING: MY HEALTH.


Assuntos
Suplementos Nutricionais/efeitos adversos , Dispepsia/dietoterapia , Dispepsia/fisiopatologia , Probióticos/uso terapêutico , Adulto , Bacillus coagulans , Bacillus subtilis , Bélgica/epidemiologia , Estudos de Casos e Controles , Método Duplo-Cego , Dispepsia/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Placebos/administração & dosagem , Prevalência , Probióticos/administração & dosagem , Probióticos/efeitos adversos , Inibidores da Bomba de Prótons/uso terapêutico , Segurança , Esporos/química , Resultado do Tratamento
3.
Artigo em Inglês | MEDLINE | ID: mdl-34224053

RESUMO

Autoimmunity is caused by an unbalanced immune system, giving rise to a variety of organ-specific to system disorders. Patients with autoimmune diseases are commonly treated with broad-acting immunomodulatory drugs, with the risk of severe side effects. Regulatory T cells (Tregs) have the inherent capacity to induce peripheral tolerance as well as tissue regeneration and are therefore a prime candidate to use as cell therapy in patients with autoimmune disorders. (Pre)clinical studies using Treg therapy have already established safety and feasibility, and some show clinical benefits. However, Tregs are known to be functionally impaired in autoimmune diseases. Therefore, ex vivo manipulation to boost and stably maintain their suppressive function is necessary when considering autologous transplantation. Similar to autoimmunity, severe coronavirus disease 2019 (COVID-19) is characterized by an exaggerated immune reaction and altered Treg responses. In light of this, Treg-based therapies are currently under investigation to treat severe COVID-19. This review provides a detailed overview of the current progress and clinical challenges of Treg therapy for autoimmune and hyperinflammatory diseases, with a focus on recent successes of ex vivo Treg manipulation.

4.
Int J Mol Sci ; 22(11)2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34073458

RESUMO

Cytotoxic CD4+ T cells (CD4 CTL) are terminally differentiated T helper cells that contribute to autoimmune diseases, such as multiple sclerosis. We developed a novel triple co-culture transwell assay to study mutual interactions between CD4 CTL, conventional TH cells, and regulatory T cells (Tregs) simultaneously. We show that, while CD4 CTL are resistant to suppression by Tregs in vitro, the conditioned medium of CD4 CTL accentuates the suppressive phenotype of Tregs by upregulating IL-10, Granzyme B, CTLA-4, and PD-1. We demonstrate that CD4 CTL conditioned medium skews memory TH cells to a TH17 phenotype, suggesting that the CD4 CTL induce bystander polarization. In our triple co-culture assay, the CD4 CTL secretome promotes the proliferation of TH cells, even in the presence of Tregs. However, when cell-cell contact is established between CD4 CTL and TH cells, the proliferation of TH cells is no longer increased and Treg-mediated suppression is restored. Taken together, our results suggest that when TH cells acquire cytotoxic properties, these Treg-resistant CD4 CTL affect the proliferation and phenotype of conventional TH cells in their vicinity. By creating such a pro-inflammatory microenvironment, CD4 CTL may favor their own persistence and expansion, and that of other potentially pathogenic TH cells, thereby contributing to pathogenic responses in autoimmune disorders.


Assuntos
Doenças Autoimunes/imunologia , Proliferação de Células , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Adulto , Antígeno CTLA-4/imunologia , Feminino , Granzimas/imunologia , Humanos , Interleucina-10/imunologia , Masculino , Pessoa de Meia-Idade , Receptor de Morte Celular Programada 1/imunologia , Linfócitos T Reguladores/citologia , Células Th17/citologia
5.
Cell Mol Life Sci ; 78(10): 4615-4637, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33751149

RESUMO

Oligodendrocyte precursor cells (OPCs) account for 5% of the resident parenchymal central nervous system glial cells. OPCs are not only a back-up for the loss of oligodendrocytes that occurs due to brain injury or inflammation-induced demyelination (remyelination) but are also pivotal in plastic processes such as learning and memory (adaptive myelination). OPC differentiation into mature myelinating oligodendrocytes is controlled by a complex transcriptional network and depends on high metabolic and mitochondrial demand. Mounting evidence shows that OPC dysfunction, culminating in the lack of OPC differentiation, mediates the progression of neurodegenerative disorders such as multiple sclerosis, Alzheimer's disease and Parkinson's disease. Importantly, neurodegeneration is characterised by oxidative and carbonyl stress, which may primarily affect OPC plasticity due to the high metabolic demand and a limited antioxidant capacity associated with this cell type. The underlying mechanisms of how oxidative/carbonyl stress disrupt OPC differentiation remain enigmatic and a focus of current research efforts. This review proposes a role for oxidative/carbonyl stress in interfering with the transcriptional and metabolic changes required for OPC differentiation. In particular, oligodendrocyte (epi)genetics, cellular defence and repair responses, mitochondrial signalling and respiration, and lipid metabolism represent key mechanisms how oxidative/carbonyl stress may hamper OPC differentiation in neurodegenerative disorders. Understanding how oxidative/carbonyl stress impacts OPC function may pave the way for future OPC-targeted treatment strategies in neurodegenerative disorders.


Assuntos
Diferenciação Celular , Doenças do Sistema Nervoso/patologia , Células Precursoras de Oligodendrócitos/patologia , Estresse Oxidativo , Animais , Humanos
6.
Mult Scler Relat Disord ; 47: 102634, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33278741

RESUMO

The Multiple Sclerosis Data Alliance (MSDA), a global multi-stakeholder collaboration, is working to accelerate research insights for innovative care and treatment for people with multiple sclerosis (MS) through better use of real-world data (RWD). Despite the increasing reliance on RWD, challenges and limitations complicate the generation, collection, and use of these data. MSDA aims to tackle sociological and technical challenges arising with scaling up RWD, specifically focused on MS data. MSDA envisions a patient-centred data ecosystem in which all stakeholders contribute and use big data to co-create the innovations needed to advance timely treatment and care of people with MS.


Assuntos
Esclerose Múltipla , Ecossistema , Humanos , Esclerose Múltipla/epidemiologia , Esclerose Múltipla/terapia , Projetos de Pesquisa
7.
J Colloid Interface Sci ; 581(Pt B): 566-575, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32818676

RESUMO

HYPOTHESIS: Conjugated polymer nanoparticles (CNPs) have attracted considerable attention within bioimaging due to their excellent optical properties and biocompatibility. However, unspecific adsorption of proteins hampers their effective use as advanced bioimaging probes. Controlled methodologies made possible tailor-made functional poly(p-phenylene vinylene), enabling one-pot synthesis of CNPs containing functional surface groups. Hence, it should be feasible to PEGylate these CNPs to tune the uptake by cell lines representative for the brain without imparting their optical properties. EXPERIMENTS: CNPs consisting of the statistical copolymer 2-(5'-methoxycarbonylpentyloxy)-5-methoxy-1,4-phenylenevinylene and poly(2-methoxy-5-(3',7'-dimethoxyoctyloxy)-1,4-phenylenevinylene) were fabricated by miniemulsion solvent evaporation technique. Surface carboxylic acid groups were used to covalently attach amine-terminated polyethylene glycol (PEG) of different molecular weights. We investigated the effect of grafting CNPs with PEG chains on their intrinsic optical properties, protein adsorption behavior and uptake by representative brain cell lines. FINDINGS: PEGylation did not affect the optical properties and biocompatibility of our CNPs. Moreover, a significant decrease in protein corona formation and unspecific uptake in central nervous system cell lines, depending on PEG chain length, was observed. This is the first report indicating that PEGylation does not affect the CNPs role as excellent bioimaging tools and can be adapted to tune biological interactions with brain cells.


Assuntos
Nanopartículas , Polivinil , Polietilenoglicóis , Polímeros
8.
Int J Mol Sci ; 21(20)2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33066042

RESUMO

Multiple sclerosis (MS) is an autoimmune inflammatory disease characterized by demyelination, axonal loss, and synaptic impairment in the central nervous system (CNS). The available therapies aim to reduce the severity of the pathology during the early inflammatory stages, but they are not effective in the chronic stage of the disease. In this phase, failure in endogenous remyelination is associated with the impairment of oligodendrocytes progenitor cells (OPCs) to migrate and differentiate into mature myelinating oligodendrocytes. Therefore, stimulating differentiation of OPCs into myelinating oligodendrocytes has become one of the main goals of new therapeutic approaches for MS. Different disease-modifying therapies targeting sphingosine-1-phosphate receptors (S1PRs) have been approved or are being developed to treat MS. Besides their immunomodulatory effects, growing evidence suggests that targeting S1PRs modulates mechanisms beyond immunomodulation, such as remyelination. In this context, this review focuses on the current understanding of S1PR modulators and their direct effect on OPCs and oligodendrocytes.


Assuntos
Esclerose Múltipla/tratamento farmacológico , Oligodendroglia/metabolismo , Moduladores do Receptor de Esfingosina 1 Fosfato/farmacologia , Receptores de Esfingosina-1-Fosfato/metabolismo , Animais , Humanos , Esclerose Múltipla/metabolismo , Bainha de Mielina/metabolismo , Oligodendroglia/efeitos dos fármacos , Moduladores do Receptor de Esfingosina 1 Fosfato/uso terapêutico
9.
Trends Mol Med ; 26(11): 1059-1060, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32978063
10.
Front Neuroinform ; 14: 28, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32765249

RESUMO

Motor Evoked Potentials (MEPs) are used to monitor disability progression in multiple sclerosis (MS). Their morphology plays an important role in this process. Currently, however, there is no clear definition of what constitutes a normal or abnormal morphology. To address this, five experts independently labeled the morphology (normal or abnormal) of the same set of 1,000 MEPs. The intra- and inter-rater agreement between the experts indicates they agree on the concept of morphology, but differ in their choice of threshold between normal and abnormal morphology. We subsequently performed an automated extraction of 5,943 time series features from the MEPs to identify a valid proxy for morphology, based on the provided labels. To do this, we compared the cross-validation performances of one-dimensional logistic regression models fitted to each of the features individually. We find that the approximate entropy (ApEn) feature can accurately reproduce the majority-vote labels. The performance of this feature is evaluated on an independent test set by comparing to the majority vote of the neurologists, obtaining an AUC score of 0.92. The model slightly outperforms the average neurologist at reproducing the neurologists consensus-vote labels. We can conclude that MEP morphology can be consistently defined by pooling the interpretations from multiple neurologists and that ApEn is a valid continuous score for this. Having an objective and reproducible MEP morphological abnormality score will allow researchers to include this feature in their models, without manual annotation becoming a bottleneck. This is crucial for large-scale, multi-center datasets. An exploratory analysis on a large single-center dataset shows that ApEn is potentially clinically useful. Introducing an automated, objective, and reproducible definition of morphology could help overcome some of the barriers that are currently obstructing broad adoption of evoked potentials in daily care and patient follow-up, such as standardization of measurements between different centers, and formulating guidelines for clinical use.

12.
Int J Mol Sci ; 21(12)2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32604901

RESUMO

Neutrophils are the most abundant circulating and first-responding innate myeloid cells and have so far been underestimated in the context of multiple sclerosis (MS). MS is the most frequent, immune-mediated, inflammatory disease of the central nervous system. MS is treatable but not curable and its cause(s) and pathogenesis remain elusive. The involvement of neutrophils in MS pathogenesis has been suggested by the use of preclinical animal disease models, as well as on the basis of patient sample analysis. In this review, we provide an overview of the possible mechanisms and functions by which neutrophils may contribute to the development and pathology of MS. Neutrophils display a broad variety of effector functions enabling disease pathogenesis, including (1) the release of inflammatory mediators and enzymes, such as interleukin-1ß, myeloperoxidase and various proteinases, (2) destruction and phagocytosis of myelin (as debris), (3) release of neutrophil extracellular traps, (4) production of reactive oxygen species, (5) breakdown of the blood-brain barrier and (6) generation and presentation of autoantigens. An important question relates to the issue of whether neutrophils exhibit a predominantly proinflammatory function or are also implicated in the resolution of chronic inflammatory responses in MS.


Assuntos
Imunidade Inata/imunologia , Mediadores da Inflamação/metabolismo , Esclerose Múltipla/patologia , Neutrófilos/patologia , Fagocitose , Espécies Reativas de Oxigênio/metabolismo , Animais , Humanos , Esclerose Múltipla/imunologia , Esclerose Múltipla/metabolismo , Neutrófilos/imunologia
13.
BMC Neurol ; 20(1): 105, 2020 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-32199461

RESUMO

BACKGROUND: Evoked potentials (EPs) are a measure of the conductivity of the central nervous system. They are used to monitor disease progression of multiple sclerosis patients. Previous studies only extracted a few variables from the EPs, which are often further condensed into a single variable: the EP score. We perform a machine learning analysis of motor EP that uses the whole time series, instead of a few variables, to predict disability progression after two years. Obtaining realistic performance estimates of this task has been difficult because of small data set sizes. We recently extracted a dataset of EPs from the Rehabiliation & MS Center in Overpelt, Belgium. Our data set is large enough to obtain, for the first time, a performance estimate on an independent test set containing different patients. METHODS: We extracted a large number of time series features from the motor EPs with the highly comparative time series analysis software package. Mutual information with the target and the Boruta method are used to find features which contain information not included in the features studied in the literature. We use random forests (RF) and logistic regression (LR) classifiers to predict disability progression after two years. Statistical significance of the performance increase when adding extra features is checked. RESULTS: Including extra time series features in motor EPs leads to a statistically significant improvement compared to using only the known features, although the effect is limited in magnitude (ΔAUC = 0.02 for RF and ΔAUC = 0.05 for LR). RF with extra time series features obtains the best performance (AUC = 0.75±0.07 (mean and standard deviation)), which is good considering the limited number of biomarkers in the model. RF (a nonlinear classifier) outperforms LR (a linear classifier). CONCLUSIONS: Using machine learning methods on EPs shows promising predictive performance. Using additional EP time series features beyond those already in use leads to a modest increase in performance. Larger datasets, preferably multi-center, are needed for further research. Given a large enough dataset, these models may be used to support clinicians in their decision making process regarding future treatment.


Assuntos
Avaliação da Deficiência , Progressão da Doença , Potencial Evocado Motor/fisiologia , Aprendizado de Máquina , Esclerose Múltipla/fisiopatologia , Bélgica , Conjuntos de Dados como Assunto , Feminino , Humanos , Modelos Logísticos , Masculino
14.
Proc Natl Acad Sci U S A ; 117(9): 5028-5038, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32071226

RESUMO

The brain's endogenous capacity to restore damaged myelin deteriorates during the course of demyelinating disorders. Currently, no treatment options are available to establish remyelination. Chronic demyelination leads to damaged axons and irreversible destruction of the central nervous system (CNS). We identified two promising therapeutic candidates which enhance remyelination: oncostatin M (OSM), a member of the interleukin-6 family, and downstream mediator tissue inhibitor of metalloproteinases-1 (TIMP-1). While remyelination was completely abrogated in OSMRß knockout (KO) mice, OSM overexpression in the chronically demyelinated CNS established remyelination. Astrocytic TIMP-1 was demonstrated to play a pivotal role in OSM-mediated remyelination. Astrocyte-derived TIMP-1 drove differentiation of oligodendrocyte precursor cells into mature oligodendrocytes in vitro. In vivo, TIMP-1 deficiency completely abolished spontaneous remyelination, phenocopying OSMRß KO mice. Finally, TIMP-1 was expressed by human astrocytes in demyelinated multiple sclerosis lesions, confirming the human value of our findings. Taken together, OSM and its downstream mediator TIMP-1 have the therapeutic potential to boost remyelination in demyelinating disorders.


Assuntos
Astrócitos/metabolismo , Oncostatina M/metabolismo , Remielinização/fisiologia , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Animais , Astrócitos/patologia , Axônios , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/patologia , Doenças Desmielinizantes/metabolismo , Doenças Desmielinizantes/patologia , Humanos , Interleucina-6/metabolismo , Camundongos , Camundongos Knockout , Esclerose Múltipla/metabolismo , Esclerose Múltipla/patologia , Bainha de Mielina , Células Precursoras de Oligodendrócitos , Inibidor Tecidual de Metaloproteinase-1/genética
15.
J Extracell Vesicles ; 10(1): e12022, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33708355

RESUMO

Microglia, the immunocompetent cells of the central nervous system (CNS), play an important role in maintaining cellular homeostasis in the CNS. These cells secrete immunomodulatory factors including nanovesicles and participate in the removal of cellular debris by phagocytosis or autophagy. Accumulating evidence indicates that specifically the cellular exchange of small extracellular vesicles (EVs), participates in physiology and disease through intercellular communication. However, the contribution of microglial-derived extracellular vesicles (M-EVs) to the maintenance of microglia homeostasis and how M-EVs could influence the phenotype and gene function of other microglia subtypes is unclear. In addition, knowledge of canonical signalling pathways of inflammation and immunity gene expression patterns in human microglia exposed to M-EVs is limited. Here, we analysed the effects of M-EVs produced in vitro by either tumour necrosis factor alpha (TNFα) activated or non-activated microglia BV2 cells. We showed that M-EVs are internalized by both mouse and human C20 microglia cells and that the uptake of M-EVs in microglia induced autophagic vesicles at various stages of degradation including autophagosomes and autolysosomes. Consistently, stimulation of microglia with M-EVs increased the protein expression of the autophagy marker, microtubule-associated proteins 1A/1B light chain 3B isoform II (LC3B-II), and promoted autophagic flux in live cells. To elucidate the biological activities occurring at the transcriptional level in C20 microglia stimulated with M-EVs, the gene expression profiles, potential upstream regulators, and enrichment pathways were characterized using targeted RNA sequencing. Inflammation and immunity transcriptome gene panel sequencing of both activated and normal microglia stimulated with M-EVs showed involvement of several canonical pathways and reduced expression of key genes involved in neuroinflammation, inflammasome and apoptosis signalling pathways compared to control cells. In this study, we provide the perspective that a beneficial activity of in vitro cell culture produced EVs could be the modulation of autophagy during cellular stress. Therefore, we use a monoculture system to study microglia-microglia crosstalk which is important in the prevention and propagation of inflammation in the brain. We demonstrate that in vitro produced microglial EVs are able to influence multiple biological pathways and promote activation of autophagy in order to maintain microglia survival and homeostasis.

16.
Cells ; 8(10)2019 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-31614602

RESUMO

Oligodendrocytes provide metabolic and functional support to neuronal cells, rendering them key players in the functioning of the central nervous system. Oligodendrocytes need to be newly formed from a pool of oligodendrocyte precursor cells (OPCs). The differentiation of OPCs into mature and myelinating cells is a multistep process, tightly controlled by spatiotemporal activation and repression of specific growth and transcription factors. While oligodendrocyte turnover is rather slow under physiological conditions, a disruption in this balanced differentiation process, for example in case of a differentiation block, could have devastating consequences during ageing and in pathological conditions, such as multiple sclerosis. Over the recent years, increasing evidence has shown that epigenetic mechanisms, such as DNA methylation, histone modifications, and microRNAs, are major contributors to OPC differentiation. In this review, we discuss how these epigenetic mechanisms orchestrate and influence oligodendrocyte maturation. These insights are a crucial starting point for studies that aim to identify the contribution of epigenetics in demyelinating diseases and may thus provide new therapeutic targets to induce myelin repair in the long run.


Assuntos
Epigênese Genética , Redes Reguladoras de Genes , Células Precursoras de Oligodendrócitos/citologia , Oligodendroglia/citologia , Animais , Diferenciação Celular , Metilação de DNA , Regulação da Expressão Gênica , Código das Histonas , Humanos , MicroRNAs/genética , Células Precursoras de Oligodendrócitos/química , Oligodendroglia/química
17.
Front Immunol ; 10: 1727, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31396231

RESUMO

Multiple sclerosis (MS) is a chronic demyelinating disease of the central nervous system (CNS) characterized by heterogeneous clinical symptoms including gradual muscle weakness, fatigue, and cognitive impairment. The disease course of MS can be classified into a relapsing-remitting (RR) phase defined by periods of neurological disabilities, and a progressive phase where neurological decline is persistent. Pathologically, MS is defined by a destructive immunological and neuro-degenerative interplay. Current treatments largely target the inflammatory processes and slow disease progression at best. Therefore, there is an urgent need to develop next-generation therapeutic strategies that target both neuroinflammatory and degenerative processes. It has been shown that elevating second messengers (cAMP and cGMP) is important for controlling inflammatory damage and inducing CNS repair. Phosphodiesterases (PDEs) have been studied extensively in a wide range of disorders as they breakdown these second messengers, rendering them crucial regulators. In this review, we provide an overview of the role of PDE inhibition in limiting pathological inflammation and stimulating regenerative processes in MS.


Assuntos
Esclerose Múltipla , Inibidores de Fosfodiesterase/uso terapêutico , Diester Fosfórico Hidrolases/imunologia , Sistemas do Segundo Mensageiro , AMP Cíclico/imunologia , GMP Cíclico/imunologia , Humanos , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/imunologia , Esclerose Múltipla/patologia , Sistemas do Segundo Mensageiro/efeitos dos fármacos , Sistemas do Segundo Mensageiro/imunologia
18.
Front Immunol ; 10: 1165, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31191538

RESUMO

For a long time, the central nervous system (CNS) was believed to be an immune privileged organ. In the last decades, it became apparent that the immune system interacts with the CNS not only in pathological, but also in homeostatic situations. It is now clear that immune cells infiltrate the healthy CNS as part of immune surveillance and that immune cells communicate through cytokines with CNS resident cells. In pathological conditions, an enhanced infiltration of immune cells takes place to fight the pathogen. A well-known family of cytokines is the interleukin (IL)-6 cytokine family. All members are important in cell communication and cell signaling in the immune system. One of these members is oncostatin M (OSM), for which the receptor is expressed on several cells of the CNS. However, the biological function of OSM in the CNS is not studied in detail. Here, we briefly describe the general aspects related to OSM biology, including signaling and receptor binding. Thereafter, the current understanding of OSM during CNS homeostasis and pathology is summarized.


Assuntos
Sistema Nervoso Central/fisiologia , Oncostatina M/genética , Oncostatina M/metabolismo , Animais , Suscetibilidade a Doenças , Homeostase , Humanos , Receptores de Oncostatina M/metabolismo , Transdução de Sinais , Especificidade da Espécie
19.
Sci Rep ; 9(1): 4908, 2019 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-30894635

RESUMO

Activation of liver X receptors (LXRs) by synthetic agonists was found to improve cognition in Alzheimer's disease (AD) mice. However, these LXR agonists induce hypertriglyceridemia and hepatic steatosis, hampering their use in the clinic. We hypothesized that phytosterols as LXR agonists enhance cognition in AD without affecting plasma and hepatic triglycerides. Phytosterols previously reported to activate LXRs were tested in a luciferase-based LXR reporter assay. Using this assay, we found that phytosterols commonly present in a Western type diet in physiological concentrations do not activate LXRs. However, a lipid extract of the 24(S)-Saringosterol-containing seaweed Sargassum fusiforme did potently activate LXRß. Dietary supplementation of crude Sargassum fusiforme or a Sargassum fusiforme-derived lipid extract to AD mice significantly improved short-term memory and reduced hippocampal Aß plaque load by 81%. Notably, none of the side effects typically induced by full synthetic LXR agonists were observed. In contrast, administration of the synthetic LXRα activator, AZ876, did not improve cognition and resulted in the accumulation of lipid droplets in the liver. Administration of Sargassum fusiforme-derived 24(S)-Saringosterol to cultured neurons reduced the secretion of Aß42. Moreover, conditioned medium from 24(S)-Saringosterol-treated astrocytes added to microglia increased phagocytosis of Aß. Our data show that Sargassum fusiforme improves cognition and alleviates AD pathology. This may be explained at least partly by 24(S)-Saringosterol-mediated LXRß activation.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/genética , Receptores X do Fígado/genética , Fármacos Neuroprotetores/farmacologia , Fragmentos de Peptídeos/genética , Placa Amiloide/tratamento farmacológico , Sargassum/química , Estigmasterol/análogos & derivados , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Compostos de Anilina/farmacologia , Animais , Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Cognição/efeitos dos fármacos , Cognição/fisiologia , Meios de Cultivo Condicionados/farmacologia , Modelos Animais de Doenças , Regulação da Expressão Gênica , Genes Reporter , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/patologia , Humanos , Receptores X do Fígado/agonistas , Receptores X do Fígado/metabolismo , Luciferases/genética , Luciferases/metabolismo , Masculino , Memória de Curto Prazo/efeitos dos fármacos , Memória de Curto Prazo/fisiologia , Camundongos , Camundongos Transgênicos , Microglia/citologia , Microglia/efeitos dos fármacos , Microglia/metabolismo , Fármacos Neuroprotetores/isolamento & purificação , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/metabolismo , Placa Amiloide/genética , Placa Amiloide/metabolismo , Placa Amiloide/fisiopatologia , Transdução de Sinais , Estigmasterol/isolamento & purificação , Estigmasterol/farmacologia , Tiazóis/farmacologia
20.
Mult Scler ; 25(4): 500-509, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30381984

RESUMO

Personalized treatment is highly desirable in multiple sclerosis (MS). We believe that multidisciplinary measurements including clinical, functional and patient-reported outcome measures in combination with extensive patient profiling can enhance personalized treatment and rehabilitation strategies. We elaborate on four reasons behind this statement: (1) MS disease activity and progression are complex and multidimensional concepts in nature and thereby defy a one-size-fits-all description, (2) functioning, progression, treatment, and rehabilitation effects are interdependent and should be investigated together, (3) personalized healthcare is based on the dynamics of system biology and on technology that confirms a patient's fundamental biology and (4) inclusion of patient-reported outcome measures can facilitate patient-relevant healthcare. We discuss currently available multidisciplinary MS data initiatives and introduce joint actions to further increase the overall success. With this topical review, we hope to drive the MS community to invest in expanding towards more multidisciplinary and longitudinal data collection.


Assuntos
Pesquisa Interdisciplinar , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/terapia , Medidas de Resultados Relatados pelo Paciente , Medicina de Precisão , Sistema de Registros , Humanos
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