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1.
Adv Exp Med Biol ; 1175: 335-353, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31583594

RESUMO

Microglia are the most abundant immune cells in the central nervous system (CNS), where they interact with neurons and exhibit a wide array of functions in physiological and pathological conditions. Physiologically, microglia mediate synaptic pruning and remodeling crucial for neural circuits and brain connectivity. In pathological conditions such as neurodegeneration in the Parkinson's disease (PD), microglia are activated, migrated to the injury site, and prone to engulf debris, sense pathology, and secrete possible pro- and anti-inflammatory factors. Microglia mediate responses such as inflammation and phagocytosis associated with neurodegeneration and are pivotal players in exacerbating or relieving disease progression. This chapter provides an overview on microglial function in the neurodegenerative disease-Parkinson's disease (PD). An overview on the pathology of PD will first be given, followed by discussion on receptors and signaling pathways involved in microglia-mediated inflammation and phagocytosis. Mechanism of how microglia contribute to PD by inflammation, phagocytosis of α-Synuclein (α-Syn), and interaction with PD genes will also be discussed.


Assuntos
Microglia/citologia , Doença de Parkinson/fisiopatologia , Humanos , Inflamação/fisiopatologia , Fagocitose , Transdução de Sinais , alfa-Sinucleína
2.
Mol Biol (Mosk) ; 53(5): 790-798, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31661478

RESUMO

Recently, much attention has been drawn to unraveling the mechanisms of neurodegenerative and neuroinflammatory disease pathogenesis. A special role in the development of neuropathologies is assigned to the interaction of the nervous and the immune systems. Microglia are the cells of the immune system that function as resident macrophages of the central nervous system (CNS) and are involved in the development of CNS, as well as in homeostatic interactions. Impaired microglia can contribute to neuroinflammation and neurodegeneration. With the help of genome editing technologies, the main paradigms in the development and functions of microglia have been addressed. At the same time, an understanding of the mechanisms of regulation of microglia in normal and pathological conditions is necessary to create an effective therapy aimed at treating various neurological diseases. This review focuses on recent findings on the origin of microglia, its regulatory role in the central nervous system, as well as its contribution to the development of neuroinflammation.


Assuntos
Sistema Nervoso Central/citologia , Sistema Nervoso Central/fisiologia , Homeostase , Inflamação/patologia , Microglia/fisiologia , Doenças Neurodegenerativas/patologia , Sistema Nervoso Central/patologia , Sistema Nervoso Central/fisiopatologia , Humanos , Inflamação/fisiopatologia , Microglia/citologia , Microglia/patologia , Doenças Neurodegenerativas/fisiopatologia
3.
Cell Biochem Funct ; 37(7): 560-568, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31479167

RESUMO

Annexin A1 (AnxA1) is a protein secreted by phagocytic cells which plays a pivotal role on the resolution of inflammation by enhancing phagocytosis carried out by phagocytes. Which factors and intracellular mechanisms are linked to such actions exerted by AnxA1 are yet to be completely understood. In order to investigate such, BV2 microglial cells were transfected with plasmids aimed at down-modulating AnxA1 expression and also treated with exogenous recombinant rAnxA1; gene and protein expression of proliferated-activated receptor γ (PPARγ) and CD36, STAT6 phosphorylation and phagocytosis of apoptotic neurons were investigated. Down-modulating AnxA1 in BV2 cells impaired gene and protein expression of PPARγ, effects reversed by treatment with recombinant AnxA1 (rAnxA1). Lower levels of CD36 were also verified in AnxA1 down-modulated BV2 cells. AnxA1-mediated phagocytosis of apoptotic cells was abrogated due to blockade of PPARγ activation, and in AnxA1 down-modulated cells exogenous AnxA1 failed to exert any effects on phagocytosis. Lower levels of STAT6/pSTAT6 in AnxA1 down-modulated BV2 cells suggest the involvement of this transcription factor with PPARγ and CD36 synthesis and actions. Data here shown suggest that there is a probable connection between AnxA1, PPARγ, and CD36, which must all act in association in order for efferocytosis to occur properly. AnxA1-mediated phosphorylation of STAT6 is probably involved with intracellular pathways involving PPARγ and CD36 actions. These data evidence that PPARγ/CD36 play a role on AnxA1-mediated efferocytosis in microglial cells. SIGNIFICANCE OF THE STUDY: The findings of this work provide evidence that the glucocorticoid-mediated protein annexin A1 modulates PPARγ expression and that PPARγ is important for annexin A1-mediated efferocytosis. Only recently the interaction between these two factors has begun to be explored, and knowledge on associated cell mechanisms are still scarce. Elucidating how annexin A1 and PPARγ interact with one another provides basis for further research aimed at understanding molecular pathways and cell signaling events involved with these factors, expanding existing knowledge on the anti-inflammatory effects of such factors.


Assuntos
Anexina A1/metabolismo , Microglia/metabolismo , PPAR gama/metabolismo , Fagocitose , Animais , Linhagem Celular , Perfilação da Expressão Gênica , Humanos , Camundongos , Microglia/citologia , PPAR gama/genética , Ratos
4.
J Biol Regul Homeost Agents ; 33(4): 1051-1062, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31392878

RESUMO

The development of electronic technology has attracted attention on the biological effects of electromagnetic fields (EMFs) and electromagnetic pulse (EMP). It remains controversial whether EMP irradiation is neurotoxic or beneficial for recovery from injuryies such as cerebral ischemia. Microglia is innate immune cells in the brain, exhibiting either neurotoxicity or neuroprotection effect during various central nervous system diseases, depending on their activation into a classical (M1) or alternative (M2) phenotype, respectively. The Toll-like receptor-4 (TLR4), myeloid differentiation factor 88 (MyD88) and nuclear factor kappa B (NFκB) pathway is important for microglia activation. In this study, we investigated the effect of EMP on neuronal apoptosis and microglia polarization in vivo and in vitro, using an EMP of 400 kV/m and 1 hertz for 200 pulses. Short EMP irradiation (≤24 h) resulted in microglial conversion from the resting to the M1-type state, activation of the TLR4/MyD88/NFκB pathway, higher levels of inflammatory cytokines including interleukin (IL)-6, IL-1ß and tumor necrosis factor-α, as well as neuronal apoptosis induction. In contrast, long EMP irradiation (3 days) resulted in microglial activation into the M2-type, decreased apoptosis and inflammatory mediator production, and increased levels of the neuroprotective effectors IL-10, transforming growth factor beta, and brain-derived neurotrophic factor. EMP induces both neuronal damage and neuronal recovery by influencing the switch of M1/M2 polarization and the TLR4/MyD88/NFκB pathway.


Assuntos
Lesões Encefálicas/patologia , Polaridade Celular , Campos Eletromagnéticos/efeitos adversos , Microglia/citologia , Citocinas/metabolismo , Humanos , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Receptor 4 Toll-Like/metabolismo
5.
Chem Pharm Bull (Tokyo) ; 67(7): 640-647, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31257319

RESUMO

Neuroinflammation manifested by over-activation of microglial cells plays an essential role in neurodegenerative diseases. Short-term activation of microglia can be beneficial, but chronically activated microglia can aggravate neuronal dysfunction possibly by secreting potentially cytotoxic substances such as tumor necrosis factor-alpha (TNF-α) and nitric oxide (NO), which can result in dysfunction and death of neurons. Therefore inhibiting over-activation of microglia and the production of cytotoxic intermediates may become an effective therapeutic approach for neuroinflammation. In this paper, we review our continuous research on natural inhibitors of over-activated microglia from traditional herbals, including flavonoids, lignans, sesquiterpene coumarins, and stilbenes.


Assuntos
Produtos Biológicos/química , Microglia/metabolismo , Animais , Produtos Biológicos/farmacologia , Cumarínicos/química , Cumarínicos/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Lignanas/química , Lignanas/farmacologia , Microglia/citologia , Microglia/efeitos dos fármacos , Óxido Nítrico/biossíntese , Estilbenos/química , Estilbenos/farmacologia , Relação Estrutura-Atividade , Fator de Necrose Tumoral alfa/metabolismo
6.
Nature ; 571(7764): 205-210, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31270459

RESUMO

The mammalian brain contains neurogenic niches that comprise neural stem cells and other cell types. Neurogenic niches become less functional with age, but how they change during ageing remains unclear. Here we perform single-cell RNA sequencing of young and old neurogenic niches in mice. The analysis of 14,685 single-cell transcriptomes reveals a decrease in activated neural stem cells, changes in endothelial cells and microglia, and an infiltration of T cells in old neurogenic niches. T cells in old brains are clonally expanded and are generally distinct from those in old blood, which suggests that they may experience specific antigens. T cells in old brains also express interferon-γ, and the subset of neural stem cells that has a high interferon response shows decreased proliferation in vivo. We find that T cells can inhibit the proliferation of neural stem cells in co-cultures and in vivo, in part by secreting interferon-γ. Our study reveals an interaction between T cells and neural stem cells in old brains, opening potential avenues through which to counteract age-related decline in brain function.


Assuntos
Envelhecimento/fisiologia , Encéfalo/citologia , Movimento Celular , Células-Tronco Neurais/citologia , Neurogênese , Análise de Célula Única , Nicho de Células-Tronco/fisiologia , Linfócitos T/citologia , Animais , Sangue , Proliferação de Células , Células Clonais/citologia , Técnicas de Cocultura , Células Endoteliais/citologia , Interferon gama/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/citologia , Análise de Sequência de RNA , Transdução de Sinais , Linfócitos T/metabolismo , Transcriptoma/genética
7.
Nat Commun ; 10(1): 2541, 2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-31186414

RESUMO

Reactive astrocytes evolve after brain injury, inflammatory and degenerative diseases, whereby they undergo transcriptomic re-programming. In malignant brain tumors, their function and crosstalk to other components of the environment is poorly understood. Here we report a distinct transcriptional phenotype of reactive astrocytes from glioblastoma linked to JAK/STAT pathway activation. Subsequently, we investigate the origin of astrocytic transformation by a microglia loss-of-function model in a human organotypic slice model with injected tumor cells. RNA-seq based gene expression analysis of astrocytes reveals a distinct astrocytic phenotype caused by the coexistence of microglia and astrocytes in the tumor environment, which leads to a large release of anti-inflammatory cytokines such as TGFß, IL10 and G-CSF. Inhibition of the JAK/STAT pathway shifts the balance of pro- and anti-inflammatory cytokines towards a pro-inflammatory environment. The complex interaction of astrocytes and microglia cells promotes an immunosuppressive environment, suggesting that tumor-associated astrocytes contribute to anti-inflammatory responses.


Assuntos
Astrócitos/metabolismo , Citocinas/metabolismo , Glioblastoma/imunologia , Microglia/metabolismo , Astrócitos/citologia , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Perfilação da Expressão Gênica , Humanos , Mediadores da Inflamação , Janus Quinases/metabolismo , Microglia/citologia , Fenótipo , Fatores de Transcrição STAT/metabolismo , Análise de Sequência de RNA , Transdução de Sinais , Técnicas de Cultura de Tecidos
8.
Carbohydr Polym ; 219: 219-228, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31151520

RESUMO

Coreopsis tinctoria is being widely cultivated in Xinjiang of China, whose consumption is known to prevent diabetes and neurodegenerative diseases. To elucidate the bioactive ingredients responsible for these benefits, the alkaline soluble crude polysaccharide (CTB) was isolated from C. tinctoria. In vitro experiments showed that the inhibition of α-amylase and α-glucosidase by CTB was 13407-fold and 906-fold higher than that by positive control, respectively. Then, a novel arabinogalactan, CTBP-1, was isolated and purified from CTB. Structural analysis showed that CTBP-1 possessed a 1,6-linked ß-d-Galp and 1,5-linked α-l-Araf backbone with branches substituted at the C-3 position of the 1,6-linked ß-d-Galp, and the side chains included 1,5-linked α-l-Araf, T-linked ß-d-Galp and T-linked α-l-Araf. The inhibitory effects of CTBP-1 on α-amylase and α-glucosidase were 2.7 and 17.9 times that of acarbose, respectively. CTBP-1 could avoid indigestion and similar side effects. In addition, CTBP-1 remarkably inhibited the release of nitric oxide (NO), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in lipopolysaccharide (LPS)-stimulated BV2 microglial cells. In summary, CTBP-1 is a novel arabinogalactan with great potential as a treatment for type 2 diabetes and Alzheimer's disease.


Assuntos
Coreopsis/metabolismo , Galactanos , Inibidores de Glicosídeo Hidrolases/farmacologia , Microglia , Extratos Vegetais/química , alfa-Amilases/antagonistas & inibidores , alfa-Glucosidases/metabolismo , Células Cultivadas , China , Galactanos/química , Galactanos/farmacologia , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , Microglia/citologia , Microglia/efeitos dos fármacos , Óxido Nítrico/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
9.
Nat Neurosci ; 22(6): 1021-1035, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31061494

RESUMO

While the roles of parenchymal microglia in brain homeostasis and disease are fairly clear, other brain-resident myeloid cells remain less well understood. By dissecting border regions and combining single-cell RNA-sequencing with high-dimensional cytometry, bulk RNA-sequencing, fate-mapping and microscopy, we reveal the diversity of non-parenchymal brain macrophages. Border-associated macrophages (BAMs) residing in the dura mater, subdural meninges and choroid plexus consisted of distinct subsets with tissue-specific transcriptional signatures, and their cellular composition changed during postnatal development. BAMs exhibited a mixed ontogeny, and subsets displayed distinct self-renewal capacity following depletion and repopulation. Single-cell and fate-mapping analysis both suggested that there is a unique microglial subset residing on the apical surface of the choroid plexus epithelium. Finally, gene network analysis and conditional deletion revealed IRF8 as a master regulator that drives the maturation and diversity of brain macrophages. Our results provide a framework for understanding host-macrophage interactions in both the healthy and diseased brain.


Assuntos
Encéfalo/citologia , Fatores Reguladores de Interferon/metabolismo , Macrófagos/citologia , Macrófagos/fisiologia , Animais , Diferenciação Celular/fisiologia , Linhagem da Célula/fisiologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/citologia
10.
Cell Biol Int ; 43(7): 809-819, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31050073

RESUMO

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


Assuntos
Peptídeos Penetradores de Células/farmacologia , Corpo Estriado/efeitos dos fármacos , Portadores de Fármacos/farmacologia , Glicoproteínas/farmacologia , Proteínas de Fluorescência Verde/metabolismo , Hipocampo/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Proteínas Virais/farmacologia , Animais , Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Corpo Estriado/citologia , Genes Reporter , Vetores Genéticos/uso terapêutico , Proteínas de Fluorescência Verde/genética , Hipocampo/citologia , Camundongos , Camundongos Endogâmicos C57BL , Microglia/citologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Oligodendroglia/citologia , Oligodendroglia/efeitos dos fármacos , Transfecção/métodos
11.
Mol Med Rep ; 19(6): 5153-5161, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31059087

RESUMO

Parkinson's disease (PD) is a common progressive neurodegenerative disorder occurring in older individuals. Mechanistically, neuroinflammation is a central pathological change in the progression of PD. Activation of microglia is widely considered to be a major trigger for neuroinflammation. Certain microRNAs (miRs) are key factors in inhibiting or stimulating inflammation during the occurrence and development of PD, among which miR­195 may be a potential crucial biomarker. However, the underlying pathological mechanisms remain unclear. To investigate the pathogenesis of PD, lipopolysaccharide (LPS) was used to establish an in vitro model of microglia activation in the present study. It was revealed that miR­195 expression was decreased in LPS­stimulated BV2 cells, suggesting a potential mechanism of action of miR­195 on microglia activation. Furthermore, gain­ and loss­of­function experiments were performed by successful transfection of microglia with miR­195 mimics or inhibitors. The results demonstrated that miR­195 overexpression inhibited the release of pro­inflammatory cytokines, including inducible nitric oxide synthase, interleukin­6 (IL­6) and tumor necrosis factor­α, but induced the release of anti­inflammatory cytokines in LPS­treated BV2 cells, including IL­4 and IL­10. In addition, Rho­associated kinase 1 (ROCK1), which is negatively regulated by miR­195, was increased in LPS­stimulated BV2 cells. ROCK1 knockdown with small interfering RNA exhibited the same effect as miR­195 overexpression on regulating microglia status, suggesting that the miR­195/ROCK1 interaction serves a central role in inducing microglia activation. Furthermore, inhibition of ROCK1 impaired cell viability and proliferation but induced cell apoptosis in LPS­treated miR­195­deficient BV2 cells. The present results suggest that miR­195 is a potential therapeutic target for PD.


Assuntos
MicroRNAs/metabolismo , Quinases Associadas a rho/metabolismo , Animais , Antagomirs/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Inflamação , Interleucina-6/genética , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Microglia/citologia , Microglia/efeitos dos fármacos , Microglia/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Quinases Associadas a rho/antagonistas & inibidores , Quinases Associadas a rho/genética
12.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(2): 164-170, 2019 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-31106533

RESUMO

OBJECTIVE: To explore the effect and mechanism of human adipose-derived mesenchymal stem cells (hADMSCs) on phenotypic polarization of microglia. METHODS: BV-2 microglia of C57/BL6 mice were co-cultured with hADMSCs+lipopolysaccharide (LPS), or cultured with LPS alone. Cell morphology was observed under an inverted microscope. The effect of hADMSCs on microglial proliferation was evaluated by CCK-8 assay. The impact of hADMSCs on microglia M1/M2 phenotype markers were detected using quantitative real-time PCR (RT-qPCR). The affect of hADMSCs on the proteins expression levels of Toll-like receptor 4 (TLR4)-TIR domain containing adaptor protein inducing interferon ß (TRIF) signaling pathway in BV-2 microglia was detected by using Western blot analysis. RESULTS: As compared with the LPS treatment, hADMSCs treatment had no obvious effect on microglia morphology, whereas showed significant inhibition on microglial proliferation activity (P<0.05). Simultaneously, hADMSCs treatment reduced expression of microglia M1 phenotype markers (P<0.05), and increased microglia M1 phenotype markers in gene levels (P<0.05). At the same time, protein expression levels of TRIF, TLR4, phosphorylated interferon regulatory factor 3 (P-IRF3) and interferon regulatory factor 3 (IRF3) in BV-2 microglia were decreased after hADMSCs treatment. CONCLUSION: hADMSCs can blockade the LPS-induced pro-inflammatory microglia M1 phenotype, whereas induces protective microglial M2 phenotype, which may be related to inhibition of the TLR4-TRIF signaling pathway.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Polaridade Celular , Células-Tronco Mesenquimais/citologia , Microglia/citologia , Transdução de Sinais , Receptor 3 Toll-Like/metabolismo , Tecido Adiposo/citologia , Animais , Células Cultivadas , Humanos , Lipopolissacarídeos , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo
13.
Chem Biodivers ; 16(5): e1900123, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30933425

RESUMO

Two previously undescribed guaiane-type sesquiterpenes (1 and 2), a pair of new salvialane-type sesquiterpenes (3a and 3b), together with 11 known compounds were isolated and purified from the rhizomes of Curcuma kwangsiensis. Their structures were elucidated by the extensive spectroscopic data (1D- and 2D-NMR) analysis. All the isolated compounds were assessed for their anti-neuroinflammatory activity by inhibiting the nitric oxide (NO) production in lipopolysaccharide (LPS)-activated murine BV-2 microglial cells in vitro assay, and the isolates 3 and 11 showed anti-neuroinflammatory activity with IC50 values of 1.85 and 20.05 µm, respectively.


Assuntos
Anti-Inflamatórios/química , Curcuma/química , Sesquiterpenos/química , Animais , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Linhagem Celular , Curcuma/metabolismo , Lipopolissacarídeos/toxicidade , Espectroscopia de Ressonância Magnética , Camundongos , Microglia/citologia , Microglia/efeitos dos fármacos , Microglia/metabolismo , Conformação Molecular , Óxido Nítrico/metabolismo , Rizoma/química , Rizoma/metabolismo , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia
14.
Food Chem Toxicol ; 129: 54-63, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30978372

RESUMO

In this study, a unique citrus species (Citrus australasica) was selected, and its fruit characteristics, phenolic compounds and ability to inhibit inflammation were preliminarily studied. Finger lime fruits showed distinctive features in shape, size, weight, colour, total soluble solids, water-soluble pectin, sugar and acids contents. Combining UPLC-HRMS and UPLC-DAD analysis, 31 phenolics, 1 secoiridoid derivative and 1 neolignan glycoside were preliminarily identified and quantified. The phenolics composition of finger limes showed cultivar and tissue specificity. Antioxidant evaluation showed that extracts from finger lime cultivar of 'XiangBin' exhibited better antioxidant capacities than cultivar of 'LiSiKe', especially in peel. LPS-induced NO-releasing model was performed in the mouse microglia BV-2 cell line. Results illustrated that finger limes inhibited the NO-releasing and the inflammation-related cytokines including IL-1ß, IL-6 and TNFα elevation. QRT-PCR revealed that finger lime extracts alleviated LPS-induced upregulation of iNOS, IL-6, JAK2, TNFα, TLR2, TLR4, IL-1ß, NF-κB and LPS-induced downregulation of IκBα. This study may expand our knowledge on the physiochemical characteristics and bioactive properties of citrus fruits.


Assuntos
Antioxidantes/farmacologia , Citrus/química , Óxido Nítrico/antagonistas & inibidores , Fenóis/farmacologia , Ácidos/metabolismo , Animais , Linhagem Celular , Cromatografia Líquida/métodos , Regulação para Baixo/efeitos dos fármacos , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/toxicidade , Camundongos , Microglia/citologia , Microglia/efeitos dos fármacos , Microglia/metabolismo , Óxido Nítrico/metabolismo , Pectinas/metabolismo , Fenóis/química , Fenóis/isolamento & purificação , Açúcares/análise , Regulação para Cima/efeitos dos fármacos
15.
Nature ; 568(7751): 187-192, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30944478

RESUMO

Microglia maintain homeostasis in the central nervous system through phagocytic clearance of protein aggregates and cellular debris. This function deteriorates during ageing and neurodegenerative disease, concomitant with cognitive decline. However, the mechanisms of impaired microglial homeostatic function and the cognitive effects of restoring this function remain unknown. We combined CRISPR-Cas9 knockout screens with RNA sequencing analysis to discover age-related genetic modifiers of microglial phagocytosis. These screens identified CD22, a canonical B cell receptor, as a negative regulator of phagocytosis that is upregulated on aged microglia. CD22 mediates the anti-phagocytic effect of α2,6-linked sialic acid, and inhibition of CD22 promotes the clearance of myelin debris, amyloid-ß oligomers and α-synuclein fibrils in vivo. Long-term central nervous system delivery of an antibody that blocks CD22 function reprograms microglia towards a homeostatic transcriptional state and improves cognitive function in aged mice. These findings elucidate a mechanism of age-related microglial impairment and a strategy to restore homeostasis in the ageing brain.


Assuntos
Envelhecimento/fisiologia , Encéfalo/citologia , Homeostase/efeitos dos fármacos , Microglia/efeitos dos fármacos , Ácido N-Acetilneuramínico/farmacologia , Fagocitose/efeitos dos fármacos , Lectina 2 Semelhante a Ig de Ligação ao Ácido Siálico/antagonistas & inibidores , Envelhecimento/efeitos dos fármacos , Envelhecimento/genética , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , Proteína 9 Associada à CRISPR/metabolismo , Sistemas CRISPR-Cas/genética , Cognição/efeitos dos fármacos , Cognição/fisiologia , Feminino , Homeostase/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/citologia , Ácido N-Acetilneuramínico/química , Fagocitose/genética , Análise de Sequência de RNA , Lectina 2 Semelhante a Ig de Ligação ao Ácido Siálico/genética , Lectina 2 Semelhante a Ig de Ligação ao Ácido Siálico/metabolismo
16.
Food Chem ; 286: 421-427, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-30827627

RESUMO

Chinese olive is served as a famous fruit and traditional herb in China. In this study, the anti-neuroinflammatory and antioxidant phytochemicals of Chinese olive fruits were investigated. Three new phenylpropanoids (2, 6, 19), together with sixteen known congeners, have been isolated and identified. A variety of bioactivities related to the traditional healthy benefits of Chinese olive, including anti-neuroinflammatory, antioxidant and antidiabetic, have been evaluated for the identified compounds. The phenylpropanoids could significantly inhibit the production of nitric oxide induced by lipopolysaccharide (LPS) in microglia cells (BV-2). Compounds 2, 6, and 19 could dose-dependently reduce the expression levels of pro-inflammatory mediator iNOS and COX-2 expressions induced by LPS in BV-2 cells. Meanwhile, some phenylpropanoids showed remarkable antioxidant and antidiabetic activities. This study suggested that Chinese olive could be served as a healthy product for neuroinflammatory related diseases, such as Alzheimer's disease.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antioxidantes/farmacologia , Burseraceae/química , Hipoglicemiantes/farmacologia , Animais , Anti-Inflamatórios não Esteroides/química , Antioxidantes/química , Linhagem Celular , China , Ciclo-Oxigenase 2/metabolismo , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Frutas/química , Hipoglicemiantes/química , Lipopolissacarídeos/farmacologia , Camundongos , Microglia/citologia , Microglia/efeitos dos fármacos , Microglia/metabolismo , Estrutura Molecular , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Plantas Medicinais/química
17.
Methods Mol Biol ; 1936: 23-36, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30820891

RESUMO

Remyelination is the regenerative process whereby myelin sheaths are restored around axons following nervous system injury, allowing reinstatement of electrical impulse conduction, trophic/metabolic support, and axon health. Failure of remyelination in progressive multiple sclerosis is considered to contribute to axon loss, a correlate of clinical decline. Lack of approved pro-regenerative therapies for MS highlights the need to understand the cellular and molecular mechanisms underpinning successful remyelination. One approach is to conduct nonbiased gene expression analyses of cell types which regulate remyelination, such as microglia and monocyte-derived macrophages. Recent technological advances address the challenges of RNA sequencing of small tissue samples, thus allowing relatively small numbers of cells to be isolated from discrete lesions for analysis. Here, we present methods for FACS-based isolation of cells from focal remyelinating lesions of the adult mouse brain and subsequent RNA extraction for sequencing, using isolation of microglia/macrophages as an example.


Assuntos
Encéfalo/citologia , Remielinização , Análise de Sequência de RNA/métodos , Animais , Separação Celular , Sistema Nervoso Central/química , Citometria de Fluxo , Regulação da Expressão Gênica , Macrófagos/química , Macrófagos/citologia , Camundongos , Microglia/química , Microglia/citologia
18.
Pharm Biol ; 57(1): 238-244, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30922159

RESUMO

CONTEXT: Osthole is a natural coumarin compound most frequently extracted from plants of the Apiaceae family such as Cnidium monnieri (L.) Cusson, Angelica pubescens Maxin.f., and Peucedanum ostruthium (L.). Osthole is considered to have potential therapeutic applications for the treatment of diseases including epilepsy. However, the mechanism of osthole induced-apoptosis in BV-2 microglia cells is not yet clear. OBJECTIVE: To investigate the molecular mechanisms underlying the effect of osthole on PI3K/AKt/mTOR expression in kainic acid (KA)-activated BV-2 microglia cells. MATERIALS AND METHODS: Optimal culture concentration and time of osthole were investigated by MTT assay. The concentration of osthole was tested from 10 to 400 µM and the culture time was tested from 2 to 72 h. Ultrastructure difference among control, KA and osthole group was analyzed under transmission electron microscope. The mRNA expression of PI3K/AKt/mTOR was investigated using reverse transcription (RT)-PCR and the protein expression was investigated using western blotting and immunofluorescence assay. Apoptosis rate of BV-2 cells between each group was measured by flow cytometry. RESULTS: IC50 for cell viability of BV-2 cells by osthole was 157.7 µM. Treated with osthole (140 µM) for 24 h significantly increased the inhibition rate. Pretreatment with osthole inhibited the KA-induced PI3K/AKt/mTOR mRNA and protein expression. The results of flow cytometry analysis showed that the apoptotic rate of osthole group was obviously higher than KA group. CONCLUSIONS: Date showed that osthole may be useful in the treatment of epilepsy and other neurodegenerative diseases that are characterized by over expression of PI3K/Akt/mTOR.


Assuntos
Cumarínicos/farmacologia , Microglia/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Ácido Caínico/farmacologia , Camundongos , Microglia/citologia , Microglia/metabolismo , Transdução de Sinais/efeitos dos fármacos
19.
Chem Biol Interact ; 305: 134-147, 2019 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-30922767

RESUMO

Methiopropamine (MPA) is structurally categorized as a thiophene ring-based methamphetamine (MA) derivative. Although abusive potential of MPA was recognized, little is known about the neurotoxic potential of MPA up to now. We investigated whether MPA induces dopaminergic neurotoxicity, and whether MPA activates a specific dopamine receptor. Here, we observed that treatment with MPA resulted in dopaminergic neurotoxicity in a dose-dependent manner. MPA treatment potentiated oxidative parameters (i.e., increases in the level of reactive oxygen species, 4-hydroxynonenal, and protein carbonyl), M1 phenotype-related microglial activity, and pro-apoptotic property (i.e., increases in Bax- and cleaved caspase-3-expressions, while a decrease in Bcl-2-expression). Moreover, treatment with MPA resulted in significant impairments in dopaminergic parameters [i.e., changes in dopamine level, dopamine turnover rate, tyrosine hydroxylase (TH) levels, dopamine transporter (DAT) expression, and vesicular monoamine transporter-2 (VMAT-2) expression], and in behavioral deficits. Both dopamine D1 receptor antagonist SCH23390 and D2 receptor antagonist sulpiride protected from these neurotoxic consequences. Therefore, our results suggest that dopamine D1 and D2 receptors simultaneously mediate MPA-induced dopaminergic neurodegeneration in mice via oxidative burdens, microgliosis, and pro-apoptosis.


Assuntos
Metanfetamina/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Benzazepinas/farmacologia , Benzazepinas/uso terapêutico , Diferenciação Celular/efeitos dos fármacos , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Dopamina/metabolismo , Antagonistas dos Receptores de Dopamina D2/farmacologia , Antagonistas dos Receptores de Dopamina D2/uso terapêutico , Febre/prevenção & controle , Locomoção/efeitos dos fármacos , Masculino , Metanfetamina/síntese química , Metanfetamina/química , Camundongos , Camundongos Endogâmicos ICR , Microglia/citologia , Microglia/efeitos dos fármacos , Microglia/metabolismo , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Receptores de Dopamina D1/antagonistas & inibidores , Receptores de Dopamina D2/química , Sulpirida/farmacologia , Sulpirida/uso terapêutico , Tirosina 3-Mono-Oxigenase/metabolismo
20.
J Zhejiang Univ Sci B ; 20(3): 205-218, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30829009

RESUMO

Spinal cord injury (SCI), which is much in the public eye, is still a refractory disease compromising the well-being of both patients and society. In spite of there being many methods dealing with the lesion, there is still a deficiency in comprehensive strategies covering all facets of this damage. Further, we should also mention the structure called the corticospinal tract (CST) which plays a crucial role in the motor responses of organisms, and it will be the focal point of our attention. In this review, we discuss a variety of strategies targeting different dimensions following SCI and some treatments that are especially efficacious to the CST are emphasized. Over recent decades, researchers have developed many effective tactics involving five approaches: (1) tackle more extensive regions; (2) provide a regenerative microenvironment; (3) provide a glial microenvironment; (4) transplantation; and (5) other auxiliary methods, for instance, rehabilitation training and electrical stimulation. We review the basic knowledge on this disease and correlative treatments. In addition, some well-formulated perspectives and hypotheses have been delineated. We emphasize that such a multifaceted problem needs combinatorial approaches, and we analyze some discrepancies in past studies. Finally, for the future, we present numerous brand-new latent tactics which have great promise for curbing SCI.


Assuntos
Tratos Piramidais/patologia , Medicina Regenerativa/métodos , Traumatismos da Medula Espinal/terapia , Animais , Astrócitos/citologia , Axônios/fisiologia , Transplante de Células , Modelos Animais de Doenças , Estimulação Elétrica , Humanos , Microglia/citologia , Neurônios Motores/citologia , Regeneração Nervosa , Neuroglia/citologia , Plasticidade Neuronal , Neurônios/citologia , Oligodendroglia/citologia , Recuperação de Função Fisiológica
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