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1.
J Agric Food Chem ; 67(35): 9796-9804, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31393712

RESUMO

Overactivated microglia and persistent neuroinflammation hold an important role in the pathophysiology of neurodegenerative diseases. The extract of Lycoris chejuensis (CJ) and its active compound, 7-deoxy-trans-dihydronarciclasine (named E144), attenuated expressions of pro-inflammatory factors, including nitric oxide, prostaglandin E2, inducible nitric oxide synthase, cyclooxygenase-2 (COX-2), tumor necrosis factor α (TNF-α), and interleukin 6, secreted by lipopolysaccharide-activated BV-2 microglial cells, as measured by an enzyme-linked immunosorbent assay or western blotting. In contrast, CJ extract and E144 promoted the secretion of the anti-inflammatory cytokine, interleukin 10. Moreover, we found that E144 attenuated the expression of TNF-α and COX-2 in the cerebral cortex of lipopolysaccharide-treated mice and/or T2576 transgenic mice as well as reduced the reactive immune cells visualized by ionized calcium-binding adaptor molecule 1. Our results suggest the possibility of E144 to serve as a potential anti-neuroinflammatory agent by preventing excess production of pro-inflammatory factors.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/imunologia , Isoquinolinas/administração & dosagem , Lycoris/química , Extratos Vegetais/administração & dosagem , Doença de Alzheimer/genética , Animais , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/imunologia , Modelos Animais de Doenças , Humanos , Interleucina-6/genética , Interleucina-6/imunologia , Isoquinolinas/química , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microglia/efeitos dos fármacos , Microglia/metabolismo , NF-kappa B/genética , NF-kappa B/imunologia , Extratos Vegetais/química , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
2.
Chem Biol Interact ; 312: 108775, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31369746

RESUMO

Postnatal exposure to valproic acid (VPA) in rodents induces autism-like neurobehavioral defects which are comparable to the motor and cognitive deficits observed in humans with autism spectrum disorder (ASD). Histamine H3 receptor (H3R) and acetylcholine esterase (AChE) are involved in several cognitive disorders such as Alzheimer's disease, schizophrenia, anxiety, and narcolepsy, all of which are comorbid with ASD. Therefore, the present study aimed at evaluating effect of the novel dual-active ligand E100 with high H3R antagonist affinity and balanced AChE inhibition on autistic-like repetitive behavior, anxiety parameters, locomotor activity, and neuroinflammation in a mouse model of VPA-induced ASD in C57BL/6 mice. E100 (5, 10, and 15 mg/kg) dose-dependently and significantly ameliorated repetitive and compulsive behaviors by reducing the increased percentages of nestlets shredded (all P < 0.05). Moreover, pretreatment with E100 (10 and 15 mg/kg) attenuated disturbed anxiety levels (P < 0.05) but failed to restore the hyperactivity observed in the open field test. Furthermore, pretreatment with E100 (10 mg/kg) the increased microglial activation, proinflammatory cytokines and expression of NF-κB, iNOS, and COX-2 in the cerebellum as well as the hippocampus (all P < 0.05). These results demonstrate the ameliorative effects of E100 on repetitive compulsive behaviors in a mouse model of ASD. To our knowledge, this is the first in vivo demonstration of the effectiveness of a potent dual-active H3R antagonist and AChE inhibitor against autistic-like repetitive compulsive behaviors and neuroinflammation, and provides evidence for the role of such compounds in treating ASD.


Assuntos
Transtorno do Espectro Autista/patologia , Comportamento Animal/efeitos dos fármacos , Inibidores da Colinesterase/farmacologia , Antagonistas dos Receptores Histamínicos H3/farmacologia , Animais , Transtorno do Espectro Autista/induzido quimicamente , Transtorno do Espectro Autista/tratamento farmacológico , Inibidores da Colinesterase/uso terapêutico , Citocinas/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Hipocampo/metabolismo , Antagonistas dos Receptores Histamínicos H3/uso terapêutico , Camundongos , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Fator de Transcrição RelA/metabolismo , Ácido Valproico/toxicidade
3.
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
5.
Chem Biol Interact ; 311: 108762, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31348917

RESUMO

Neurotoxicity caused by particulate matter (PM) has been highlighted as being a potential risk factor for neurodegenerative diseases. However, the effects of brain inflammation in response to traffic-related PM remain unclear. The objective of this study was to investigate the effects of traffic-related PM on microglial responses. We determined the cytotoxicity, oxidative stress, lipid peroxidation, inflammation, activation, autophagy, and apoptosis due to exposure to carbon black (CB) and diesel exhaust particles (DEPs) in Bv2 microglial cells. Additionally, cells were pretreated with corticosteroid to determine alterations in microglial activation and inflammation. For in vivo confirmation, Sprague Dawley (SD) rats were whole-body exposed to traffic-related PM1 (PM with an aerodynamic diameter of <1 µm) for 3 and 6 months. We observed that a decrease in cell viability and increases in dichlorodihydrofluorescein (DCFH), lactate dehydrogenase (LDH), and thiobarbituric acid-reactive substances (TBARSs) occurred due to CB and DEP. Production of interleukin (IL)-6 and soluble tumor necrosis factor (TNF)-α was significantly stimulated by CB and DEP, whereas production of cellular TNF-α was significantly stimulated by CB. Iba1 and prostaglandin E2 (PGE2) significantly increased due to CB and DEP. Consistently, we observed significant increases in Iba1 in the hippocampus of rats after 3 and 6 months of exposure to traffic-related PM1. We found that the light chain 3II (LC3II)/LC3I ratio and caspase-3 activity increased due to CB and DEP exposure. Subsequently, LDH, TBARS, LC3II/I, and caspase-3 activities did not clearly respond to corticosteroid pretreatment followed by DEP exposure in BV2 cells. Results of the present study suggested that traffic-related PM induced cytotoxicity, lipid peroxidation, microglial activation, and inflammation as well as autophagy and caspase-3 regulation in microglia. We demonstrated that microglial activation and inflammation may play important roles in the response of the brain to traffic-related PM.


Assuntos
Inflamação/etiologia , Microglia/efeitos dos fármacos , Material Particulado/toxicidade , Animais , Autofagia/efeitos dos fármacos , Encéfalo/patologia , Proteínas de Ligação ao Cálcio/análise , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Dinoprostona/análise , Interleucina-6/metabolismo , L-Lactato Desidrogenase/metabolismo , Masculino , Proteínas dos Microfilamentos/análise , Microglia/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima/efeitos dos fármacos , Emissões de Veículos/toxicidade
6.
Toxicol Lett ; 314: 106-116, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31306743

RESUMO

Chronic low-level lead exposure alters cognitive function in young children however the mechanisms mediating these deficits in the brain are not known. Previous studies in our laboratory showed that early lead exposure reduced the number of microglial cells in hippocampus/dentate gyrus of C57BL/6 J mice. In the current study, C-C chemokine receptor 7 (CCR7) and major histocompatibility complex II (MHC II) were examined to investigate whether these neuroimmune factors which are known to trigger cell migration and antigen presentation, were altered by early chronic lead exposure. Thirty-six C57BL/6 J male mice were exposed to 0 ppm (controls, n = 12), 30 ppm (low-dose, n = 12), or 430 ppm (higher-dose, n = 12) of lead acetate via dams' milk from postnatal day (PND) 0 to 28. Flow cytometry was used to quantify cell types and cell surface expression of MHC II and CCR7 in hippocampal and whole brain microglia. Non-parametric independent samples median tests were used to test for statistically significant differences between groups. As compared to controls, CCR7 in hippocampal microglia was decreased in the low-dose group, measured as geometric mean fluorescence intensity (GMFI); in the higher-dose group CCR7+MHC II- hippocampal microglia were decreased. Further analyses revealed that the higher-dose group had decreased percentage of CCR7+MHC II- hippocampal macrophages as compared to controls but increased MHC II levels in CCR7+MHC II+ hippocampal macrophages as compared to controls. It was also noted that lead exposure disrupted the balance of MHC II and/or CCR7 in lead exposed animals. Reduced CCR7 in hippocampal microglia might alter the neuroimmune environment in hippocampi of lead exposed animals. Additional studies are needed to test this possibility.


Assuntos
Hipocampo/efeitos dos fármacos , Intoxicação do Sistema Nervoso por Chumbo na Infância/etiologia , Microglia/efeitos dos fármacos , Compostos Organometálicos/toxicidade , Receptores CCR7/metabolismo , Animais , Animais Recém-Nascidos , Regulação para Baixo , Feminino , Hipocampo/metabolismo , Hipocampo/patologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Lactação , Intoxicação do Sistema Nervoso por Chumbo na Infância/metabolismo , Intoxicação do Sistema Nervoso por Chumbo na Infância/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Microglia/patologia , Fatores de Tempo
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.
Spine (Phila Pa 1976) ; 44(12): E707-E714, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-31150368

RESUMO

STUDY DESIGN: The effect of triptolide on spinal cord injury (SCI) and inflammatory response was observed by establishing SCI rat model. And in vitro experiments were conducted to determine the underlying mechanism of triptolide-mediated in murine microglial cell line BV2. OBJECTIVE: To determine the underlying mechanism of triptolide in suppressing the microglia activation to improve SCI. SUMMARY OF BACKGROUND DATA: Triptolide, as a major active ingredient of Chinese herb Tripterygium wilfordii, can promote spinal cord repair through inhibiting microglia activation, but the underlying mechanism is not clear. METHODS: Locomotion recovery was accessed by Basso, Beattie, and Bresnahan score, the number of footfalls, stride length, and angle of rotation analysis. Expressions of microRNA 96 (miR-96), microglia activation marker Iba-1, and IκB kinase (IKKß)/nuclear factor (NF)-κB-related proteins were detected by qRT-PCR or western blot. Inflammatory cytokines tumor necrosis factor-α and interleukin -1ß were measured by enzyme-linked immuno sorbent assay. The regulation of miR-96 on IKKß was confirmed by dual luciferase reporter assay. RESULTS: Triptolide promoted locomotion recovery of SCI rats, upregulated the expression of miR-96, decreased microglia activation marker Iba-1 and IKKß/NF-κB-related proteins, and inhibited inflammatory cytokines tumor necrosis factor-α and interleukin-1ß levels in spinal cord tissues and lipopolysaccharide -induced microglia. Triptolide suppressed the microglia activation and inflammatory cytokines secretion in BV2 cells through up-regulating miR-96. We confirmed the interaction between miR-96 and IKKß, and IKKß expression was negatively regulated by miR-96. Finally, we determined that triptolide suppressed the microglia activation and inflammatory cytokines secretion through miR-96/IKKß pathway. CONCLUSION: Triptolide suppressed microglia activation after SCI through miR-96/IKKß/NF-κB pathway. LEVEL OF EVIDENCE: N/A.


Assuntos
Diterpenos/uso terapêutico , Quinase I-kappa B/biossíntese , MicroRNAs/biossíntese , Microglia/metabolismo , NF-kappa B/biossíntese , Fenantrenos/uso terapêutico , Traumatismos da Medula Espinal/metabolismo , Animais , Diterpenos/farmacologia , Compostos de Epóxi/farmacologia , Compostos de Epóxi/uso terapêutico , Quinase I-kappa B/antagonistas & inibidores , Imunossupressores/farmacologia , Imunossupressores/uso terapêutico , Lipopolissacarídeos/toxicidade , Locomoção/efeitos dos fármacos , Locomoção/fisiologia , Masculino , Camundongos , Microglia/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , Fenantrenos/farmacologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Traumatismos da Medula Espinal/tratamento farmacológico
9.
Mar Drugs ; 17(5)2019 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-31060323

RESUMO

High intraocular pressure (IOP)-induced retinal ischemia leads to acute glaucoma, which is one of the leading causes of irreversible visual-field loss, characterized by loss of retinal ganglion cells (RGCs) and axonal injury in optic nerves (ONs). Oxidative stress and the inflammatory response play an important role in the ischemic injury of retinal and optic nerves. We focus on 5α-androst-3ß, 5α, 6ß-triol (TRIOL), a synthetic neuroactive derivative of natural marine steroids 24-methylene-cholest-3ß, 5α, 6ß, 19-tetrol and cholestane-3ß, 5α, 6ß-triol, which are two neuroactive polyhydroxysterols isolated from the soft coral Nephthea brassica and the gorgonian Menella kanisa, respectively. We previously demonstrated that TRIOL was a neuroprotective steroid with anti-inflammatory and antioxidative activities. However, the potential role of TRIOL on acute glaucoma and its underlying mechanisms remains unclear. Here, we report TRIOL as a promising neuroprotectant that can protect RGCs and their axons/dendrites from ischemic-reperfusion (I/R) injury in an acute intraocular hypertension (AIH) model. Intravitreal injection of TRIOL significantly alleviated the loss of RGCs and the damage of axons and dendrites in rats and mice with acute glaucoma. As NF-E2-related factor 2 (Nrf2) is one of the most critical regulators in oxidative and inflammatory injury, we further evaluated the effect of TRIOL on Nrf2 knockout mice, and the neuroprotective role of TRIOL on retinal ischemia was not observed in Nrf2 knockout mice, indicating that activation of Nrf2 is responsible for the neuroprotection of TRIOL. Further experiments demonstrated that TRIOL can activate and upregulate Nrf2, along with its downstream hemeoxygenase-1 (HO-1), by negative regulation of Kelch-like ECH (Enoyl-CoA Hydratase) associated Protein-1 (Keap1). In conclusion, our study shed new light on the neuroprotective therapy of retinal ischemia and proposed a promising marine drug candidate, TRIOL, for the therapeutics of acute glaucoma.


Assuntos
Androstanóis/farmacologia , Fator 2 Relacionado a NF-E2/deficiência , Fármacos Neuroprotetores/farmacologia , Traumatismo por Reperfusão/tratamento farmacológico , Células Ganglionares da Retina/efeitos dos fármacos , Esteroides/farmacologia , Animais , Técnicas de Cultura de Células , Hipóxia Celular/efeitos dos fármacos , Modelos Animais de Doenças , Glaucoma , Heme Oxigenase-1/metabolismo , Inflamação/tratamento farmacológico , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microglia/efeitos dos fármacos , Microglia/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Hipertensão Ocular/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
10.
Chin J Traumatol ; 22(3): 161-165, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31056470

RESUMO

PURPOSE: To investigate whether dexmedetomidine (Dex) can reduce the production of inflammatory factor IL-1ß by inhibiting the activation of NLRP3 inflammasome in hippocampal microglia, thereby alleviating the inflammatory response of the central nervous system induced by surgical injury. METHODS: Exploratory laparotomy was used in experimental models in this study. Totally 48 Sprague Dawley male rats were randomly divided into 4 groups (n = 12 for each), respectively sham control (group A), laparotomy only (group B); and Dex treatment with different doses of 5 µg/kg (group D1) or 10 µg/kg (group D2). Rats in groups D1 and D2 were intraperitoneally injected with corresponding doses of Dex every 6 h. The rats were sacrificed 12 h after operation; the hippocampus tissues were isolated, and frozen sections were made. The microglia activation was estimated by immunohistochemistry. The protein expression of NLRP3, caspase-1, ASC and IL-1ß were detected by immunoblotting. All data were presented as mean ± standard deviation, and independent sample t test was used to analyze the statistical difference between groups. RESULTS: The activated microglia in the hippocampus of the rats significantly increased after laparotomy (group B vs. sham control, p < 0.01). After Dex treatment, the number was decreased in a dose-dependent way (group D1 vs. D2, p < 0.05), however the activated microglia in both groups were still higher than that of sham controls (both p < 0.05). Further Western blot analysis showed that the protein expression levels of NLRP3, caspase-1, ASC and downstream cytokine IL-1ß in the hippocampus from the laparotomy group were significantly higher than those of the sham control group (all p < 0.01). The elevated expression of these proteins was relieved after Dex treatment, also in a dose-dependent way (D2 vs. D1 group, p < 0.05). CONCLUSION: Dex can inhibit the activation of microglia and NLRP3 inflammasome in the hippocampus of rats after operation, and the synthesis and secretion of IL-1ß are also reduced in a dose-dependent manner by using Dex. Hence, Dex can alleviate inflammation activation on the central nervous system induced by surgical injury.


Assuntos
Dexmedetomidina/farmacologia , Hipocampo/metabolismo , Inflamassomos/metabolismo , Mediadores da Inflamação/metabolismo , Interleucina-1beta/metabolismo , Laparotomia/efeitos adversos , Microglia/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Animais , Dexmedetomidina/administração & dosagem , Relação Dose-Resposta a Droga , Imuno-Histoquímica , Injeções Intraperitoneais , Masculino , Ratos Sprague-Dawley , Fatores de Tempo
11.
Int J Mol Sci ; 20(10)2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31096580

RESUMO

Vascular cognitive impairment (VCI) is the second most common cause of cognitive deficit after Alzheimer's disease. Since VCI patients represent an important target population for prevention, an ongoing effort has been made to elucidate the pathogenesis of this disorder. In this review, we summarize the information from animal models on the molecular changes that occur in the brain during a cerebral vascular insult and ultimately lead to cognitive deficits in VCI. Animal models cannot effectively represent the complex clinical picture of VCI in humans. Nonetheless, they allow some understanding of the important molecular mechanisms leading to cognitive deficits. VCI may be caused by various mechanisms and metabolic pathways. The pathological mechanisms, in terms of cognitive deficits, may span from oxidative stress to vascular clearance of toxic waste products (such as amyloid beta) and from neuroinflammation to impaired function of microglia, astrocytes, pericytes, and endothelial cells. Impaired production of elements of the immune response, such as cytokines, and vascular factors, such as insulin-like growth factor 1 (IGF-1), may also affect cognitive functions. No single event could be seen as being the unique cause of cognitive deficits in VCI. These events are interconnected, and may produce cascade effects resulting in cognitive impairment.


Assuntos
Cognição , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/patologia , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Astrócitos/metabolismo , Encéfalo/metabolismo , Citocinas/metabolismo , Células Endoteliais/metabolismo , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Microglia/metabolismo , Modelos Animais , Óxido Nítrico , Estresse Oxidativo , Pericitos/metabolismo
12.
Nat Cell Biol ; 21(5): 614-626, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31036939

RESUMO

Cell growth is controlled by a lysosomal signalling complex containing Rag small GTPases and mammalian target of rapamycin complex 1 (mTORC1) kinase. Here, we carried out a microscopy-based genome-wide human short interfering RNA screen and discovered a lysosome-localized G protein-coupled receptor (GPCR)-like protein, GPR137B, that interacts with Rag GTPases, increases Rag localization and activity, and thereby regulates mTORC1 translocation and activity. High GPR137B expression can recruit and activate mTORC1 in the absence of amino acids. Furthermore, GPR137B also regulates the dissociation of activated Rag from lysosomes, suggesting that GPR137B controls a cycle of Rag activation and dissociation from lysosomes. GPR137B-knockout cells exhibited defective autophagy and an expanded lysosome compartment, similar to Rag-knockout cells. Like zebrafish RagA mutants, GPR137B-mutant zebrafish had upregulated TFEB target gene expression and an expanded lysosome compartment in microglia. Thus, GPR137B is a GPCR-like lysosomal regulatory protein that controls dynamic Rag and mTORC1 localization and activity as well as lysosome morphology.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Genoma Humano/genética , Proteínas Monoméricas de Ligação ao GTP/genética , Receptores Acoplados a Proteínas-G/genética , Animais , Autofagia/genética , Regulação da Expressão Gênica/genética , Humanos , Lisossomos/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Microglia/metabolismo , Complexos Multiproteicos/química , Complexos Multiproteicos/genética , RNA Interferente Pequeno/genética , Receptores Acoplados a Proteínas-G/antagonistas & inibidores , Peixe-Zebra/genética , Peixe-Zebra/crescimento & desenvolvimento
13.
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
14.
Int J Mol Sci ; 20(9)2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-31083359

RESUMO

The overactivation of microglia is known to trigger inflammatory reactions in the central nervous system, which ultimately induce neuroinflammatory disorders including Alzheimer's disease. However, increasing evidence has shown that menaquinone-4 (MK-4), a subtype of vitamin K2, can attenuate inflammation in the peripheral system. Whereas it was also observed at high levels within the brain, its function in this organ has not been well characterized. Therefore, we investigated the effect of MK-4 on microglial activation and clarified the underlying mechanism. Mouse microglia-derived MG6 cells were exposed to lipopolysaccharide (LPS) either with or without MK-4 pretreatment. Cell responses with respect to inflammatory cytokines (Il-1ß, Tnf-α, and Il-6) were measured by qRT-PCR. We further analyzed the phosphorylation of TAK1, IKKα/ß, and p65 of the NF-κB subunit by Western blotting. We observed that in LPS-induced MG6 cells, MK-4 dose-dependently suppressed the upregulation of inflammatory cytokines at the mRNA level. It also significantly decreased the phosphorylation of p65, but did not affect that TAK1 and IKKα/ß. Furthermore, the nuclear translocation of NF-κB in LPS-induced MG6 cells was inhibited by MK-4. These results indicate that MK-4 attenuates microglial inflammation by inhibiting NF-κB signaling.


Assuntos
Inflamação/metabolismo , Inflamação/patologia , Microglia/metabolismo , Microglia/patologia , NF-kappa B/metabolismo , Transdução de Sinais , Vitamina K 2/análogos & derivados , Animais , Linhagem Celular , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Humanos , Inflamação/induzido quimicamente , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos , Camundongos , Microglia/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Vitamina K/análogos & derivados , Vitamina K 2/farmacologia
15.
Nat Med ; 25(6): 988-1000, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31086348

RESUMO

An aged circulatory environment can activate microglia, reduce neural precursor cell activity and impair cognition in mice. We hypothesized that brain endothelial cells (BECs) mediate at least some of these effects. We observe that BECs in the aged mouse hippocampus express an inflammatory transcriptional profile with focal upregulation of vascular cell adhesion molecule 1 (VCAM1), a protein that facilitates vascular-immune cell interactions. Concomitantly, levels of the shed, soluble form of VCAM1 are prominently increased in the plasma of aged humans and mice, and their plasma is sufficient to increase VCAM1 expression in cultured BECs and the hippocampi of young mice. Systemic administration of anti-VCAM1 antibody or genetic ablation of Vcam1 in BECs counteracts the detrimental effects of plasma from aged individuals on young brains and reverses aging aspects, including microglial reactivity and cognitive deficits, in the brains of aged mice. Together, these findings establish brain endothelial VCAM1 at the blood-brain barrier as a possible target to treat age-related neurodegeneration.


Assuntos
Envelhecimento/sangue , Encéfalo/metabolismo , Células-Tronco Neurais/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo , Adolescente , Adulto , Idoso , Envelhecimento/imunologia , Envelhecimento/metabolismo , Animais , Barreira Hematoencefálica/imunologia , Barreira Hematoencefálica/metabolismo , Encéfalo/citologia , Células Cultivadas , Células Endoteliais/metabolismo , Feminino , Deleção de Genes , Hipocampo/citologia , Hipocampo/metabolismo , Humanos , Mediadores da Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Microglia/metabolismo , Células-Tronco Neurais/citologia , Molécula 1 de Adesão de Célula Vascular/sangue , Molécula 1 de Adesão de Célula Vascular/genética , Adulto Jovem
16.
Oxid Med Cell Longev ; 2019: 3549274, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31049133

RESUMO

Activated microglia-mediated neuroinflammation plays a key pathogenic role in neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, multiple sclerosis, and ischemia. Sulforaphane is an active compound produced after conversion of glucoraphanin by the myrosinase enzyme in broccoli (Brassica oleracea var) sprouts. Dietary broccoli extract as well as sulforaphane has previously known to mitigate inflammatory conditions in aged models involving microglial activation. Here, we produced sulforaphane-enriched broccoli sprouts through the pretreatment of pulsed electric fields in order to trigger the biological role of normal broccoli against lipopolysaccharide-activated microglia. The sulforaphane-enriched broccoli sprouts showed excellent potency against neuroinflammation conditions, as evidenced by its protective effects in both 6 and 24 h of microglial activation in vitro. We further postulated the underlying mechanism of action of sulforaphane in broccoli sprouts, which was the inhibition of an inflammatory cascade via the downregulation of mitogen-activated protein kinase (MAPK) signaling. Simultaneously, sulforaphane-enriched broccoli sprouts inhibited the LPS-induced activation of the NF-κB signaling pathway and the secretions of inflammatory proteins (iNOS, COX-2, TNF-α, IL-6, IL-1ß, PGE2, etc.), which are responsible for the inflammatory cascades in both acute and chronic inflammation. It also upregulated the expression of Nrf2 and HO-1 in normal and activated microglia followed by the lowered neuronal apoptosis induced by activated microglia. Based on these results, it may exhibit anti-inflammatory effects via the NF-κB and Nrf2 pathways. Interestingly, sulforaphane-enriched broccoli sprouts improved the scopolamine-induced memory impairment in mice through Nrf2 activation, inhibiting neuronal apoptosis particularly through inhibition of caspase-3 activation which could lead to the neuroprotection against neurodegenerative disorders. The present study suggests that sulforaphane-enriched broccoli sprouts might be a potential nutraceutical with antineuroinflammatory and neuroprotective activities.


Assuntos
Amnésia , Brassica/química , Heme Oxigenase-1/metabolismo , Isotiocianatos , Fator 2 Relacionado a NF-E2/metabolismo , Escopolamina/efeitos adversos , Amnésia/induzido quimicamente , Amnésia/tratamento farmacológico , Amnésia/metabolismo , Amnésia/patologia , Animais , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/patologia , Isotiocianatos/química , Isotiocianatos/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Microglia/metabolismo , Microglia/patologia , Escopolamina/farmacologia
17.
Mol Med Rep ; 19(6): 4597-4602, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31059032

RESUMO

Ubiquilin­1 (Ubqln), a ubiquitin­like protein, regulates degradation of misfolded proteins and has been reported to have a crucial role in multiple pathologic and physiologic conditions. The current study was undertaken to investigate the expression of Ubqln in the brain of a neonatal hypoxia­ischemic (HI) brain injury model induced using the Rice method with some modifications. Mouse pups at postnatal day 7 day were used in this study. Pups underwent permanent ligation of the left common carotid artery and a consecutive hypoxic challenge (8% O2 and 92% N2 for 120 min). The expression of Ubqln in the brain of pups following HI was analyzed by immunofluorescence staining and western blot analysis. Immunofluorescence staining demonstrated that Ubqln was extensively distributed in the cerebral cortex and hippocampus, and Ubqln was expressed in neurons, astrocytes and microglia in the brains of the HI brain injury model mice. Western blot analyses revealed decreased expression of Ubqln in the HI penumbra of the mouse model compared with Ubqln in the sham control group. The results of this study revealed that HI alters the expression of Ubqln, thus may provide a novel understanding of role of Ubqln in neonatal hypoxic ischemic encephalopathy.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/genética , Regulação para Baixo , Hipóxia-Isquemia Encefálica/genética , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Animais , Animais Recém-Nascidos , Astrócitos/metabolismo , Western Blotting , Lesões Encefálicas/genética , Lesões Encefálicas/metabolismo , Córtex Cerebral/metabolismo , Modelos Animais de Doenças , Feminino , Hipocampo/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Masculino , Camundongos , Microglia/metabolismo , Neurônios/metabolismo
18.
Mol Immunol ; 112: 30-39, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31075560

RESUMO

Traumatic brain injury (TBI) is a major cause of motor and cognitive impairment in young adults. It is associated with high mortality rates and very few effective treatment options. Bisperoxovanadium (pyridine-2-carboxyl) [bpV(pic)] is an commercially available inhibitor of Phosphatase and tensin homolog (PTEN). Previous studies have shown that bpV(pic) has protective effects in central nervous system. However, the role of bpV(pic) in TBI is unclear. In this study we aimed to investigate the neuroprotective role of bpV(pic) in rat TBI model. We found that injection of bpV(pic) significantly reduces brain edema and neurological dysfunction after TBI and this is mediated by AKT pathway. TBI is known to promote the M1 pro-inflammatory phenotype of microglial polarization and this effect is inhibited by bpV(pic) treatment which, instead promotes M2 microglial polarization in vivo and in vitro. We also found evidence of bpV(pic)-regulated neuroinflammation mediated by AKT activation and NF-κB p65 inhibition. BpV(pic) treatment also suppressed microglia in the peri-TBI region. MCP-1 is known to recruit monocytes and macrophages to promote inflammation, we show that bpV(pic) can inhibit TBI-induced up-regulation of MCP-1 via the AKT/NF-κB p65 signaling pathway. Taken together, our findings demonstrate that bpV(pic) plays a neuroprotective role in rat TBI, which may be achieved by inhibiting M1 microglia polarization and MCP-1 expression by modulating AKT/NF-κB p65 signaling pathway.


Assuntos
Lesões Encefálicas Traumáticas/tratamento farmacológico , Lesões Encefálicas Traumáticas/metabolismo , Quimiocina CCL2/metabolismo , Microglia/efeitos dos fármacos , Neuroproteção/efeitos dos fármacos , Compostos Organometálicos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Microglia/metabolismo , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , NF-kappa B/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley
19.
Nat Immunol ; 20(5): 559-570, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30996332

RESUMO

The C-type lectin receptor-Syk (spleen tyrosine kinase) adaptor CARD9 facilitates protective antifungal immunity within the central nervous system (CNS), as human deficiency in CARD9 causes susceptibility to fungus-specific, CNS-targeted infection. CARD9 promotes the recruitment of neutrophils to the fungus-infected CNS, which mediates fungal clearance. In the present study we investigated host and pathogen factors that promote protective neutrophil recruitment during invasion of the CNS by Candida albicans. The cytokine IL-1ß served an essential function in CNS antifungal immunity by driving production of the chemokine CXCL1, which recruited neutrophils expressing the chemokine receptor CXCR2. Neutrophil-recruiting production of IL-1ß and CXCL1 was induced in microglia by the fungus-secreted toxin Candidalysin, in a manner dependent on the kinase p38 and the transcription factor c-Fos. Notably, microglia relied on CARD9 for production of IL-1ß, via both transcriptional regulation of Il1b and inflammasome activation, and of CXCL1 in the fungus-infected CNS. Microglia-specific Card9 deletion impaired the production of IL-1ß and CXCL1 and neutrophil recruitment, and increased fungal proliferation in the CNS. Thus, an intricate network of host-pathogen interactions promotes antifungal immunity in the CNS; this is impaired in human deficiency in CARD9, which leads to fungal disease of the CNS.


Assuntos
Proteínas Adaptadoras de Sinalização CARD/imunologia , Candidíase/imunologia , Quimiocina CXCL1/imunologia , Interleucina-1beta/imunologia , Microglia/imunologia , Neutrófilos/imunologia , Animais , Encéfalo/imunologia , Encéfalo/metabolismo , Encéfalo/microbiologia , Proteínas Adaptadoras de Sinalização CARD/genética , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Candida albicans/imunologia , Candida albicans/fisiologia , Candidíase/genética , Candidíase/microbiologia , Quimiocina CXCL1/genética , Quimiocina CXCL1/metabolismo , Citocinas/genética , Citocinas/imunologia , Citocinas/metabolismo , Interações Hospedeiro-Patógeno/imunologia , Inflamassomos/genética , Inflamassomos/imunologia , Inflamassomos/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Camundongos Knockout , Camundongos Transgênicos , Microglia/metabolismo , Microglia/microbiologia , Infiltração de Neutrófilos/genética , Infiltração de Neutrófilos/imunologia , Neutrófilos/metabolismo , Neutrófilos/microbiologia
20.
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
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