Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 34
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Int J Mol Sci ; 25(4)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38396755

RESUMO

Brain diseases are oftentimes life-threatening and difficult to treat. The local administration of drug substances using brain implants can increase on-site concentrations and decrease systemic side effects. However, the biocompatibility of potential brain implant materials needs to be evaluated carefully as implants can trigger foreign body reactions, particularly by increasing the microglia and astrocyte reactivity. To date, these tests have been frequently conducted in very simple in vitro models, in particular not respecting the key players in glial cell reactions and the challenges of surgical implantation characterized by the disruption of oxygen and nutrient supply. Thus, we established an in vitro model in which we treated human glial cell lines with reduced oxygen and glucose levels. The model displayed cytokine and reactive oxygen species release from reactive microglia and an increase in a marker of reactive astrocytes, galectin-3. Moreover, the treatment caused changes in the cell survival and triggered the production of hypoxia-inducible factor 1α. In this comprehensive platform, we demonstrated the protective effect of the natural polyphenol resveratrol as a model substance, which might be included in brain implants to ease the undesired glial cell response. Overall, a glial-cell-based in vitro model of the initial challenges of local brain disease treatment may prove useful for investigating new therapy options.


Assuntos
Encefalopatias , Neuroglia , Humanos , Resveratrol/farmacologia , Resveratrol/metabolismo , Neuroglia/metabolismo , Astrócitos/metabolismo , Microglia/metabolismo , Encefalopatias/metabolismo , Oxigênio/metabolismo
2.
J Neural Transm (Vienna) ; 129(9): 1095-1103, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-34816335

RESUMO

Alpha-synuclein deposits, the pathological hallmarks of Parkinson's disease, are consistently found in the gastrointestinal tract of parkinsonian subjects. These observations have raised the potential that endoscopically obtainable mucosal biopsies can aid to a molecular diagnosis of the disease. The possible usefulness of mucosal biopsies is, however, not limited to the detection of alpha-synuclein, but also extends to other essential aspects underlying pathophysiological mechanisms of gastrointestinal manifestations in Parkinson's disease. The aim of the current review is to provide an appraisal of the existing studies showing that gastrointestinal biopsies can be used for the analysis of enteric neuronal and glial cell morphology, intestinal epithelial barrier function, and gastrointestinal inflammation in Parkinson's disease. A perspective on the generation of organoids with GI biopsies and the potential use of single-cell and spatial transcriptomic technologies will be also addressed.


Assuntos
Doença de Parkinson , alfa-Sinucleína , Biópsia , Trato Gastrointestinal/química , Trato Gastrointestinal/patologia , Humanos , Neurônios/patologia , Doença de Parkinson/diagnóstico , alfa-Sinucleína/análise
3.
Gut ; 2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33888516

RESUMO

OBJECTIVE: Haemorrhoidal disease (HEM) affects a large and silently suffering fraction of the population but its aetiology, including suspected genetic predisposition, is poorly understood. We report the first genome-wide association study (GWAS) meta-analysis to identify genetic risk factors for HEM to date. DESIGN: We conducted a GWAS meta-analysis of 218 920 patients with HEM and 725 213 controls of European ancestry. Using GWAS summary statistics, we performed multiple genetic correlation analyses between HEM and other traits as well as calculated HEM polygenic risk scores (PRS) and evaluated their translational potential in independent datasets. Using functional annotation of GWAS results, we identified HEM candidate genes, which differential expression and coexpression in HEM tissues were evaluated employing RNA-seq analyses. The localisation of expressed proteins at selected loci was investigated by immunohistochemistry. RESULTS: We demonstrate modest heritability and genetic correlation of HEM with several other diseases from the GI, neuroaffective and cardiovascular domains. HEM PRS validated in 180 435 individuals from independent datasets allowed the identification of those at risk and correlated with younger age of onset and recurrent surgery. We identified 102 independent HEM risk loci harbouring genes whose expression is enriched in blood vessels and GI tissues, and in pathways associated with smooth muscles, epithelial and endothelial development and morphogenesis. Network transcriptomic analyses highlighted HEM gene coexpression modules that are relevant to the development and integrity of the musculoskeletal and epidermal systems, and the organisation of the extracellular matrix. CONCLUSION: HEM has a genetic component that predisposes to smooth muscle, epithelial and connective tissue dysfunction.

4.
Neurochem Res ; 46(7): 1781-1793, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33864170

RESUMO

Increasing evidences indicate that the enteric nervous system (ENS) and enteric glial cells (EGC) play important regulatory roles in intestinal inflammation. Mercaptopurine (6-MP) is a cytostatic compound clinically used for the treatment of inflammatory bowel diseases (IBD), such as ulcerative colitis and Crohn's disease. However, potential impacts of 6-MP on ENS response to inflammation have not been evaluated yet. In this study, we aimed to gain deeper insights into the profile of inflammatory mediators expressed by the ENS and on the potential anti-inflammatory impact of 6-MP in this context. Genome-wide expression analyses were performed on ENS primary cultures exposed to lipopolysaccharide (LPS) and 6-MP alone or in combination. Differential expression of main hits was validated by quantitative real-time PCR (qPCR) using a cell line for EGC. ENS cells expressed a broad spectrum of cytokines and chemokines of the C-X-C motif ligand (CXCL) family under inflammatory stress. Induction of Cxcl5 and Cxcl10 by inflammatory stimuli was confirmed in EGC. Inflammation-induced protein secretion of TNF-α and Cxcl5 was partly inhibited by 6-MP in ENS primary cultures but not in EGC. Further work is required to identify the cellular mechanisms involved in this regulation. These findings extend our knowledge of the anti-inflammatory properties of 6-MP related to the ENS and in particular of the EGC-response to inflammatory stimuli.


Assuntos
Anti-Inflamatórios/farmacologia , Expressão Gênica/efeitos dos fármacos , Interleucina-1beta/genética , Mercaptopurina/farmacologia , Neurônios/efeitos dos fármacos , Fator de Necrose Tumoral alfa/genética , Animais , Células Cultivadas , Sistema Nervoso Entérico/citologia , Inflamação/induzido quimicamente , Interleucina-1beta/metabolismo , Interleucina-1beta/farmacologia , Lipopolissacarídeos , Camundongos , Ratos , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
5.
Gut ; 68(5): 854-865, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30661054

RESUMO

OBJECTIVE: Diverticular disease is a common complex disorder characterised by mucosal outpouchings of the colonic wall that manifests through complications such as diverticulitis, perforation and bleeding. We report the to date largest genome-wide association study (GWAS) to identify genetic risk factors for diverticular disease. DESIGN: Discovery GWAS analysis was performed on UK Biobank imputed genotypes using 31 964 cases and 419 135 controls of European descent. Associations were replicated in a European sample of 3893 cases and 2829 diverticula-free controls and evaluated for risk contribution to diverticulitis and uncomplicated diverticulosis. Transcripts at top 20 replicating loci were analysed by real-time quatitative PCR in preparations of the mucosal, submucosal and muscular layer of colon. The localisation of expressed protein at selected loci was investigated by immunohistochemistry. RESULTS: We discovered 48 risk loci, of which 12 are novel, with genome-wide significance and consistent OR in the replication sample. Nominal replication (p<0.05) was observed for 27 loci, and additional 8 in meta-analysis with a population-based cohort. The most significant novel risk variant rs9960286 is located near CTAGE1 with a p value of 2.3×10-10 and 0.002 (ORallelic=1.14 (95% CI 1.05 to 1.24)) in the replication analysis. Four loci showed stronger effects for diverticulitis, PHGR1 (OR 1.32, 95% CI 1.12 to 1.56), FAM155A-2 (OR 1.21, 95% CI 1.04 to 1.42), CALCB (OR 1.17, 95% CI 1.03 to 1.33) and S100A10 (OR 1.17, 95% CI 1.03 to 1.33). CONCLUSION: In silico analyses point to diverticulosis primarily as a disorder of intestinal neuromuscular function and of impaired connective fibre support, while an additional diverticulitis risk might be conferred by epithelial dysfunction.


Assuntos
Doenças do Colo/genética , Tecido Conjuntivo/fisiologia , Doenças Diverticulares/genética , Epitélio/fisiologia , Estudo de Associação Genômica Ampla , Junção Neuromuscular/fisiologia , Adulto , Idoso , Estudos de Casos e Controles , Doenças do Colo/patologia , Bases de Dados Genéticas , Doenças Diverticulares/patologia , Feminino , Predisposição Genética para Doença/genética , Humanos , Masculino , Pessoa de Meia-Idade , Reino Unido
6.
J Clin Gastroenterol ; 53(6): 449-456, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-29517710

RESUMO

BACKGROUND: Diverticular disease (DD) is a common gastrointestinal inflammatory disorder associated with an enteric neuropathy. Although enteric glial cells (EGCs) are essential regulators of intestinal inflammation and motility functions, their contribution to the pathophysiology of DD remains unclear. Therefore, we analyzed the expression of specific EGC markers in patients with DD. MATERIALS AND METHODS: Expression of the glial markers S100ß, GFAP, Sox10, and Connexin 43 was analyzed by real-time quantitative PCR in colonic specimens of patients with DD and in that of controls. Protein expression levels of S100ß, GFAP, and Connexin 43 were further analyzed using immunohistochemistry in the submucosal and myenteric plexus of patients with DD and in that of controls. Expression of the inflammatory cytokines tumor necrosis factor-α and interleukin-6 was quantified using qPCR, and infiltration of CD3+ lymphocytes was determined using immunohistochemistry. RESULTS: Expression of S100ß was increased in the submucosal and myenteric plexus of patients with DD compared with that in controls, whereas expression of other glial factors remained unchanged. This increased expression of S100ß was correlated to CD3+ lymphocytic infiltrates in patients with DD, whereas no correlation was observed in controls. CONCLUSIONS: DD is associated with limited but significant alterations of the enteric glial network. The increased expression of S100ß is associated with a persistent low-grade inflammation reported in patients with DD, further emphasizing the role of EGCs in intestinal inflammation.


Assuntos
Doenças Diverticulares/fisiopatologia , Inflamação/fisiopatologia , Neuroglia/metabolismo , Subunidade beta da Proteína Ligante de Cálcio S100/genética , Idoso , Doenças Diverticulares/genética , Feminino , Regulação da Expressão Gênica , Humanos , Imuno-Histoquímica , Inflamação/genética , Masculino , Pessoa de Meia-Idade , Plexo Mientérico/metabolismo
7.
J Physiol ; 595(2): 583-598, 2017 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-27436013

RESUMO

KEY POINTS: Unlike astrocytes in the brain, the potential role of enteric glial cells (EGCs) in the formation of the enteric neuronal circuit is currently unknown. To examine the role of EGCs in the formation of the neuronal network, we developed a novel neuron-enriched culture model from embryonic rat intestine grown in indirect coculture with EGCs. We found that EGCs shape axonal complexity and synapse density in enteric neurons, through purinergic- and glial cell line-derived neurotrophic factor-dependent pathways. Using a novel and valuable culture model to study enteric neuron-glia interactions, our study identified EGCs as a key cellular actor regulating neuronal network maturation. ABSTRACT: In the nervous system, the formation of neuronal circuitry results from a complex and coordinated action of intrinsic and extrinsic factors. In the CNS, extrinsic mediators derived from astrocytes have been shown to play a key role in neuronal maturation, including dendritic shaping, axon guidance and synaptogenesis. In the enteric nervous system (ENS), the potential role of enteric glial cells (EGCs) in the maturation of developing enteric neuronal circuit is currently unknown. A major obstacle in addressing this question is the difficulty in obtaining a valuable experimental model in which enteric neurons could be isolated and maintained without EGCs. We adapted a cell culture method previously developed for CNS neurons to establish a neuron-enriched primary culture from embryonic rat intestine which was cultured in indirect coculture with EGCs. We demonstrated that enteric neurons grown in such conditions showed several structural, phenotypic and functional hallmarks of proper development and maturation. However, when neurons were grown without EGCs, the complexity of the axonal arbour and the density of synapses were markedly reduced, suggesting that glial-derived factors contribute strongly to the formation of the neuronal circuitry. We found that these effects played by EGCs were mediated in part through purinergic P2Y1 receptor- and glial cell line-derived neurotrophic factor-dependent pathways. Using a novel and valuable culture model to study enteric neuron-glia interactions, our study identified EGCs as a key cellular actor required for neuronal network maturation.


Assuntos
Intestinos/embriologia , Neurogênese/fisiologia , Neuroglia/fisiologia , Neurônios/fisiologia , Animais , Células Cultivadas , Técnicas de Cocultura , Embrião de Mamíferos , Feminino , Intestinos/citologia , Gravidez , Ratos Sprague-Dawley
8.
Acta Neuropathol ; 134(2): 281-295, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28620692

RESUMO

Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system (CNS) in young adults that has serious negative socioeconomic effects. In addition to symptoms caused by CNS pathology, the majority of MS patients frequently exhibit gastrointestinal dysfunction, which was previously either explained by the presence of spinal cord lesions or not directly linked to the autoimmune etiology of the disease. Here, we studied the enteric nervous system (ENS) in a B cell- and antibody-dependent mouse model of MS by immunohistochemistry and electron microscopy at different stages of the disease. ENS degeneration was evident prior to the development of CNS lesions and the onset of neurological deficits in mice. The pathology was antibody mediated and caused a significant decrease in gastrointestinal motility, which was associated with ENS gliosis and neuronal loss. We identified autoantibodies against four potential target antigens derived from enteric glia and/or neurons by immunoprecipitation and mass spectrometry. Antibodies against three of the target antigens were also present in the plasma of MS patients as confirmed by ELISA. The analysis of human colon resectates provided evidence of gliosis and ENS degeneration in MS patients compared to non-MS controls. For the first time, this study establishes a pathomechanistic link between the well-established autoimmune attack on the CNS and ENS pathology in MS, which might provide a paradigm shift in our current understanding of the immunopathogenesis of the disease with broad diagnostic and therapeutic implications.


Assuntos
Autoanticorpos/sangue , Gastroenteropatias/etiologia , Esclerose Múltipla , Animais , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/patologia , Citocinas/metabolismo , Modelos Animais de Doenças , Sistema Nervoso Entérico/metabolismo , Sistema Nervoso Entérico/patologia , Sistema Nervoso Entérico/ultraestrutura , Feminino , Adjuvante de Freund/toxicidade , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Esclerose Múltipla/complicações , Esclerose Múltipla/imunologia , Esclerose Múltipla/patologia , Músculo Liso/patologia , Músculo Liso/ultraestrutura , Proteína Básica da Mielina/imunologia , Proteína Básica da Mielina/metabolismo , Proteína Básica da Mielina/toxicidade , Glicoproteína Mielina-Oligodendrócito/imunologia , Glicoproteína Mielina-Oligodendrócito/toxicidade , Plexo Mientérico/patologia , Plexo Mientérico/ultraestrutura , Proteínas Recombinantes de Fusão/imunologia , Proteínas Recombinantes de Fusão/toxicidade , Tubulina (Proteína)/metabolismo
9.
Am J Physiol Gastrointest Liver Physiol ; 310(11): G941-51, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27056724

RESUMO

The postnatal period is crucial for the development of gastrointestinal (GI) functions. The enteric nervous system is a key regulator of GI functions, and increasing evidences indicate that 1) postnatal maturation of enteric neurons affect the development of GI functions, and 2) microbiota-derived short-chain fatty acids can be involved in this maturation. Although enteric glial cells (EGC) are central regulators of GI functions, the postnatal evolution of their phenotype remains poorly defined. We thus characterized the postnatal evolution of EGC phenotype in the colon of rat pups and studied the effect of short-chain fatty acids on their maturation. We showed an increased expression of the glial markers GFAP and S100ß during the first postnatal week. As demonstrated by immunohistochemistry, a structured myenteric glial network was observed at 36 days in the rat colons. Butyrate inhibited EGC proliferation in vivo and in vitro but had no effect on glial marker expression. These results indicate that the EGC myenteric network continues to develop after birth, and luminal factors such as butyrate endogenously produced in the colon may affect this development.


Assuntos
Butiratos/farmacologia , Plexo Mientérico/citologia , Neurogênese , Neuroglia/metabolismo , Animais , Linhagem Celular , Células Cultivadas , Colo/citologia , Colo/crescimento & desenvolvimento , Colo/inervação , Colo/metabolismo , Ácidos Graxos/metabolismo , Feminino , Proteína Glial Fibrilar Ácida/genética , Proteína Glial Fibrilar Ácida/metabolismo , Plexo Mientérico/crescimento & desenvolvimento , Plexo Mientérico/metabolismo , Neuroglia/citologia , Neuroglia/efeitos dos fármacos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fenótipo , Ratos , Ratos Sprague-Dawley , Proteínas S100/genética , Proteínas S100/metabolismo
11.
J Neuroinflammation ; 11: 202, 2014 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-25497784

RESUMO

BACKGROUND: Evidence continues to mount concerning the importance of the enteric nervous system (ENS) in controlling numerous intestinal functions in addition to motility and epithelial functions. Nevertheless, little is known concerning the direct participation of the ENS in the inflammatory response of the gut during infectious or inflammatory insults. In the present study we analyzed the ENS response to bacterial lipopolysaccharide, in particular the production of a major proinflammatory cytokine, tumor necrosis factor-alpha (TNF-α). METHODS: TNF-α expression (measured by qPCR, quantitative Polymerase Chain Reaction) and production (measured by ELISA) were measured in human longitudinal muscle-myenteric plexus (LMMP) and rat ENS primary cultures (rENSpc). They were either treated or not treated with lipopolysaccharide (LPS) in the presence or not of electrical field stimulation (EFS). Activation of extracellular signal-regulated kinase (ERK) and 5'-adenosine monophosphate-activated protein kinase (AMPK) pathways was analyzed by immunocytochemistry and Western blot analysis. Their implications were studied using specific inhibitors (U0126, mitogen-activated protein kinase kinase, MEK, inhibitor and C compound, AMPK inhibitor). We also analyzed toll-like receptor 2 (TLR2) expression and interleukin-6 (IL-6) production after LPS treatment simultaneously with EFS or TNF-α-neutralizing antibody. RESULTS: Treatment of human LMMP or rENSpc with LPS induced an increase in TNF-α production. Activation of the ENS by EFS significantly inhibited TNF-α production. This regulation occurred at the transcriptional level. Signaling analyses showed that LPS induced activation of ERK but not AMPK, which was constitutively activated in rENSpc neurons. Both U0126 and C compound almost completely prevented LPS-induced TNF-α production. In the presence of LPS, EFS inhibited the ERK and AMPK pathways. In addition, we demonstrated using TNF-α-neutralizing antibody that LPS-induced TNF-α production increased TLR2 expression and reduced IL-6 production. CONCLUSIONS: Our results show that LPS induced TNF-α production by enteric neurons through activation of the canonical ERK pathway and also in an AMPK-dependent manner. ENS activation through the inhibition of these pathways decreased TNF-α production, thereby modulating the inflammatory response induced by endotoxin.


Assuntos
Sistema Nervoso Entérico/metabolismo , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/toxicidade , Neurônios/metabolismo , Animais , Células Cultivadas , Sistema Nervoso Entérico/efeitos dos fármacos , Humanos , Neurônios/efeitos dos fármacos , Técnicas de Cultura de Órgãos , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/biossíntese
12.
Biomed Pharmacother ; 163: 114814, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37148859

RESUMO

Neuroinflammation is both cause and effect of many neurodegenerative disorders. Activation of astrocytes and microglia leads to the release of cytokines and reactive oxygen species followed by blood-brain barrier leakage and neurotoxicity. Transient neuroinflammation is considered to be largely protective, however, chronic neuroinflammation contributes to the pathology of Alzheimer's disease, multiple sclerosis, traumatic brain injury, and many more. In this study, we focus on the aspect of cytokine-induced neuroinflammation in human microglia and astrocytes. Here we show by mRNA and protein analysis that cytokines, released not only by microglia but also by astrocytes, lead to a circuit of proinflammatory activation. Moreover, we present how the natural compound resveratrol can stop the circuit of proinflammatory activation and facilitate return to resting conditions. These results will contribute to distinguishing between the causes and the effects of neuroinflammation, a better understanding of underlying mechanisms, and potential treatment options.


Assuntos
Citocinas , Doenças Neuroinflamatórias , Humanos , Resveratrol/farmacologia , Citocinas/metabolismo , Neuroglia/metabolismo , Microglia , Astrócitos , Inflamação/metabolismo
13.
J Mol Neurosci ; 73(7-8): 539-548, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37369878

RESUMO

Dispatched homolog (DISP) proteins have been implicated in the regulation of hedgehog signaling during embryologic development. Although DISP2 has recently been associated with neuronal development and control of cognitive functions, its localization pattern in the mammalian central and peripheral nervous system has not yet been investigated. In this study, the Disp2 expression profile was assessed in human tissues from publicly available transcriptomic datasets. The DISP2 localization pattern was further characterized in the human and rat central nervous system (CNS), as well as within the colonic enteric nervous system (ENS) using dual-label immunohistochemistry. Colocalization of DISP2 with neuronal and glial markers was additionally analyzed in murine primary ENS culture. At transcriptomic level, DISP2 expression was predominant in neuronal cell types of the CNS and ENS. DISP2 immunoreactivity was mainly located within PGP9.5-positive neurons rather than in S100-positive glial cells throughout the nervous system. Investigation of human and rat brain tissues, colonic specimens, and murine ENS primary cultures revealed that DISP2 was located in neuronal cell somata, as well as along neuronal processes both in the human and murine CNS and ENS. Our results indicate that DISP2 is prominently localized within neuronal cells of the CNS and ENS and support putative functions of DISP2 in these tissues.


Assuntos
Sistema Nervoso Entérico , Proteínas Hedgehog , Ratos , Camundongos , Animais , Humanos , Proteínas Hedgehog/metabolismo , Neurônios/metabolismo , Neuroglia , Mamíferos
14.
Antioxidants (Basel) ; 12(6)2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37371977

RESUMO

The recognition of the role of microglia cells in neurodegenerative diseases has steadily increased over the past few years. There is growing evidence that the uncontrolled and persisting activation of microglial cells is involved in the progression of diseases such as Alzheimer's or Parkinson's disease. The inflammatory activation of microglia cells is often accompanied by a switch in metabolism to higher glucose consumption and aerobic glycolysis. In this study, we investigate the changes induced by the natural antioxidant resveratrol in a human microglia cell line. Resveratrol is renowned for its neuroprotective properties, but little is known about its direct effect on human microglia cells. By analyzing a variety of inflammatory, neuroprotective, and metabolic aspects, resveratrol was observed to reduce inflammasome activity, increase the release of insulin-like growth factor 1, decrease glucose uptake, lower mitochondrial activity, and attenuate cellular metabolism in a 1H NMR-based analysis of whole-cell extracts. To this end, studies were mainly performed by analyzing the effect of exogenous stressors such as lipopolysaccharide or interferon gamma on the metabolic profile of microglial cells. Therefore, this study focuses on changes in metabolism without any exogenous stressors, demonstrating how resveratrol might provide protection from persisting neuroinflammation.

15.
Hum Mol Genet ; 19(12): 2409-20, 2010 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-20308050

RESUMO

The HMG-domain containing transcription factor Sox10 is essential for neural crest (NC) development and for oligodendrocyte differentiation. Heterozygous SOX10 mutations in humans lead to corresponding defects in several NC-derived lineages and to leukodystrophies. Disease phenotypes range from Waardenburg syndrome and Waardenburg-Hirschsprung disease to Peripheral demyelinating neuropathy, Central dysmyelination, Waardenburg syndrome and Hirschsprung disease (PCWH). The phenotypic variability can partly be explained by the action of modifier genes, but is also influenced by the mutation that leads to haploinsufficiency in some and to mutant SOX10 proteins with altered properties in other cases. Here, we used in ovo electroporation in the developing neural tube of chicken to determine which regions and properties of SOX10 are required for early NC development. We found a strict reliance on the DNA-binding activity and the presence of the C-terminal transactivation domain and a lesser influence of the dimerization function and a conserved domain in the center of the protein. Intriguingly, dominant-negative effects on early NC development were mostly observed for truncated SOX10 proteins whose production in patients is probably prevented by nonsense-mediated decay. In contrast, mutant SOX10 proteins that occur in patients were usually inactive. Any dominant negative activity which some of these mutants undoubtedly possess must, therefore, be restricted to single NC-derived cell lineages or oligodendrocytes at later times. This contributes to the phenotypic variability of human SOX10 mutations.


Assuntos
Crista Neural/anormalidades , Defeitos do Tubo Neural/genética , Tubo Neural/metabolismo , Fatores de Transcrição SOXE/genética , Animais , Apoptose/genética , Embrião de Galinha , Doenças Desmielinizantes/genética , Eletroporação , Doença de Hirschsprung/genética , Humanos , Mutação , Tubo Neural/crescimento & desenvolvimento , Tubo Neural/patologia , Defeitos do Tubo Neural/patologia , Estrutura Terciária de Proteína , Fatores de Transcrição SOXE/química , Fatores de Transcrição SOXE/metabolismo , Medula Espinal/embriologia , Medula Espinal/metabolismo , Síndrome de Waardenburg/genética
16.
Am J Physiol Gastrointest Liver Physiol ; 302(12): G1373-80, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22492692

RESUMO

Postnatal changes in the enteric nervous system (ENS) are involved in the establishment of colonic motility. In adult rats, butyrate induced neuroplastic changes in the ENS, leading to enhanced colonic motility. Whether butyrate can induce similar changes during the postnatal period remains unknown. Enemas (Na-butyrate) were performed daily in rat pups between postnatal day (PND) 7 and PND 17. Effects of butyrate were evaluated on morphological and histological parameters in the distal colon at PND 21. The neurochemical phenotype of colonic submucosal and myenteric neurons was analyzed using antibodies against Hu, choline acetyltransferase (ChAT), and neuronal nitric oxide synthase (nNOS). Colonic motility and neuromuscular transmission was assessed in vivo and ex vivo. Butyrate (2.5 mM) enemas had no impact on pup growth and histological parameters compared with control. Butyrate did not modify the number of Hu-immunoreactive (IR) neurons per ganglia. A significant increase in the proportion (per Hu-IR neurons) of nNOS-IR myenteric and submucosal neurons and ChAT-IR myenteric neurons was observed in the distal colon after butyrate enemas compared with control. In addition, butyrate induced a significant increase in both nitrergic and cholinergic components of the neuromuscular transmission compared with control. Finally, butyrate increased distal colonic transit time compared with control. We concluded that butyrate enemas induced neuroplastic changes in myenteric and submucosal neurons, leading to changes in gastrointestinal functions. Our results support exploration of butyrate as potential therapy for motility disorders in preterm infants with delayed maturation of the ENS.


Assuntos
Butiratos/administração & dosagem , Colo/efeitos dos fármacos , Plexo Mientérico/efeitos dos fármacos , Junção Neuromuscular/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Acetilcolina/metabolismo , Animais , Animais Recém-Nascidos , Colina O-Acetiltransferase/metabolismo , Neurônios Colinérgicos/efeitos dos fármacos , Neurônios Colinérgicos/metabolismo , Colo/inervação , Colo/metabolismo , Enema , Motilidade Gastrointestinal/efeitos dos fármacos , Plexo Mientérico/metabolismo , Neurônios/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Permeabilidade/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
17.
Cells ; 11(19)2022 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-36231069

RESUMO

Sodium-glucose cotransporter 2 (SGLT2) inhibitors, including empagliflozin, are routinely used as antidiabetic drugs. Recent studies indicate that beside its beneficial effects on blood glucose level, empagliflozin may also exert vascular anti-inflammatory and neuroprotective properties. In the brain, microglia are crucial mediators of inflammation, and neuroinflammation plays a key role in neurodegenerative disorders. Dampening microglia-mediated inflammation may slow down disease progression. In this context, we investigated the immunomodulatory effect of empagliflozin on activated primary microglia. As a validated experimental model, rat primary microglial cells were activated into a pro-inflammatory state by stimulation with LPS. The influence of empagliflozin on the expression of pro-inflammatory mediators (NO, Nos2, IL6, TNF, IL1B) and on the anti-inflammatory mediator IL10 was assessed using quantitative PCR and ELISA. Further, we investigated changes in the activation of the ERK1/2 cascade by Western blot and NFkB translocation by immunostaining. We observed that empagliflozin reduces the expression of pro- and anti-inflammatory mediators in LPS-activated primary microglia. These effects might be mediated by NHE-1, rather than by SGLT2, and by the further inhibition of the ERK1/2 and NFkB pathways. Our results support putative anti-inflammatory effects of empagliflozin on microglia and suggest that SGLT2 inhibitors may exert beneficial effects in neurodegenerative disorders.


Assuntos
Inibidores do Transportador 2 de Sódio-Glicose , Animais , Anti-Inflamatórios/metabolismo , Anti-Inflamatórios/farmacologia , Compostos Benzidrílicos , Glicemia/metabolismo , Glucosídeos , Hipoglicemiantes/farmacologia , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Mediadores da Inflamação/metabolismo , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , Microglia/metabolismo , NF-kappa B/metabolismo , Ratos , Sódio/metabolismo , Transportador 2 de Glucose-Sódio/metabolismo , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia
18.
Metabolites ; 12(12)2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36557259

RESUMO

Neurodegenerative diseases such as Parkinson's (PD) and Alzheimer's disease (AD), the prevalence of which is rapidly rising due to an aging world population and westernization of lifestyles, are expected to put a strong socioeconomic burden on health systems worldwide. Clinical trials of therapies against PD and AD have only shown limited success so far. Therefore, research has extended its scope to a systems medicine point of view, with a particular focus on the gastrointestinal-brain axis as a potential main actor in disease development and progression. Microbiome and metabolome studies have already revealed important insights into disease mechanisms. Both the microbiome and metabolome can be easily manipulated by dietary and lifestyle interventions, and might thus offer novel, readily available therapeutic options to prevent the onset as well as the progression of PD and AD. This review summarizes our current knowledge on the interplay between microbiota, metabolites, and neurodegeneration along the gastrointestinal-brain axis. We further illustrate state-of-the art methods of microbiome and metabolome research as well as metabolic modeling that facilitate the identification of disease pathomechanisms. We conclude with therapeutic options to modulate microbiome composition to prevent or delay neurodegeneration and illustrate potential future research directions to fight PD and AD.

19.
Dev Biol ; 341(1): 267-81, 2010 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-20144603

RESUMO

Neural crest cells and oligodendrocytes as the myelinating glia of the central nervous system exist only in vertebrates. Their development is regulated by complex regulatory networks, of which the SoxE-type high-mobility-group domain transcription factors Sox8, Sox9 and Sox10 are essential components. Here we analyzed by in ovo electroporation in chicken and by gene replacement in the mouse whether the Drosophila ortholog Sox100B can functionally substitute for vertebrate SoxE proteins. Sox100B overexpression in the chicken neural tube led to the induction of neural crest cells as previously observed for vertebrate SoxE proteins. Furthermore, many aspects of neural crest and oligodendrocyte development were surprisingly normal in mice in which the Sox10 coding information was replaced by Sox100B arguing that Sox100B integrates well into the gene-regulatory networks that drive these processes. Our results therefore provide strong evidence for a model in which SoxE proteins were co-opted to these gene-regulatory networks mainly through the acquisition of novel expression patterns. However, later developmental defects in several neural crest derived lineages in mice homozygous for the Sox100B replacement allele indicate that some degree of functional specialization and adaptation of SoxE protein properties have taken place in addition to the co-option event.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Redes Reguladoras de Genes , Fatores de Transcrição SOX9/metabolismo , Fatores de Transcrição SOXE/metabolismo , Glândulas Suprarrenais/embriologia , Animais , Galinhas , Gânglios Espinais/metabolismo , Camundongos , Crista Neural/metabolismo , Oligodendroglia/metabolismo , Células de Schwann/metabolismo , Sistema Nervoso Simpático/embriologia
20.
J Parkinsons Dis ; 11(1): 171-176, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33337386

RESUMO

Still little is known about the nature of the gastrointestinal pathological alterations occurring in Parkinson's disease (PD). Here, we used multiplexed mRNA profiling to measure the expression of a panel of 770 genes related to neuropathological processes in deep submucosal rectal biopsies of PD patients and healthy controls. Altered enteric neuropathological traits based on the expression of 22 genes related to neuroglial and mitochondrial functions, vesicle trafficking and inflammation was observed in 9 out of 12 PD patients in comparison to healthy controls. These results provide new evidences that intestinal neuropathological alterations may occur in a large proportion of PD patients.


Assuntos
Sistema Nervoso Entérico , Perfilação da Expressão Gênica , Inflamação , Mucosa Intestinal , Doença de Parkinson , RNA Mensageiro/metabolismo , Reto , Idoso , Biópsia , Sistema Nervoso Entérico/metabolismo , Sistema Nervoso Entérico/patologia , Feminino , Humanos , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Reto/metabolismo , Reto/patologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA