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1.
Hum Mol Genet ; 33(11): 935-944, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38382647

RESUMO

Many genes with distinct molecular functions have been linked to genetically heterogeneous amyotrophic lateral sclerosis (ALS), including SuperOxide Dismutase 1 (SOD1) and Valosin-Containing Protein (VCP). SOD1 converts superoxide to oxygen and hydrogen peroxide. VCP acts as a chaperon to regulate protein degradation and synthesis and various other cellular responses. Although the functions of these two genes differ, in the current report we show that overexpression of wild-type VCP in mice enhances lifespan and maintains the size of neuromuscular junctions (NMJs) of both male and female SOD1G93A mice, a well-known ALS mouse model. Although VCP exerts multiple functions, its regulation of ER formation and consequent protein synthesis has been shown to play the most important role in controlling dendritic spine formation and social and memory behaviors. Given that SOD1 mutation results in protein accumulation and aggregation, it may direct VCP to the protein degradation pathway, thereby impairing protein synthesis. Since we previously showed that the protein synthesis defects caused by Vcp deficiency can be improved by leucine supplementation, to confirm the role of the VCP-protein synthesis pathway in SOD1-linked ALS, we applied leucine supplementation to SOD1G93A mice and, similar to Vcp overexpression, we found that it extends SOD1G93A mouse lifespan. In addition, the phenotypes of reduced muscle strength and fewer NMJs of SOD1G93A mice are also improved by leucine supplementation. These results support the existence of crosstalk between SOD1 and VCP and suggest a critical role for protein synthesis in ASL. Our study also implies a potential therapeutic treatment for ALS.


Assuntos
Esclerose Lateral Amiotrófica , Modelos Animais de Doenças , Leucina , Longevidade , Camundongos Transgênicos , Junção Neuromuscular , Fenótipo , Superóxido Dismutase-1 , Proteína com Valosina , Animais , Proteína com Valosina/metabolismo , Proteína com Valosina/genética , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Camundongos , Junção Neuromuscular/metabolismo , Feminino , Masculino , Longevidade/genética , Leucina/farmacologia , Leucina/metabolismo , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Humanos , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo
2.
J Biomed Sci ; 25(1): 2, 2018 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-29310658

RESUMO

The endoplasmic reticulum (ER) is the biggest organelle in cells and is involved in versatile cellular processes. Formation and maintenance of ER morphology are regulated by a series of proteins controlling membrane fusion and curvature. At least six different ER morphology regulators have been demonstrated to be involved in neurological disorders-including Valosin-containing protein (VCP), Atlastin-1 (ATL1), Spastin (SPAST), Reticulon 2 (RTN2), Receptor expression enhancing protein 1 (REEP1) and RAB10-suggesting a critical role of ER formation in neuronal activity and function. Among these genes, mutations in VCP gene involve in inclusion body myopathy with Paget disease of bone and frontotemporal dementia (IBMPFD), familial amyotrophic lateral sclerosis (ALS), autism spectrum disorders (ASD), and hereditary spastic paraplegia (HSP). ATL1 is also one of causative genes of HSP. RAB10 is associated with Parkinson's disease (PD). A recent study showed that VCP and ATL1 work together to regulate dendritic spine formation by controlling ER formation and consequent protein synthesis efficiency. RAB10 shares the same function with VCP and ATL1 to control ER formation and protein synthesis efficiency but acts independently. Increased protein synthesis by adding extra leucine to cultured neurons ameliorated dendritic spine deficits caused by VCP and ATL1 deficiencies, strengthening the significance of protein synthesis in VCP- and ATL1-regulated dendritic spine formation. These findings provide new insight into the roles of ER and protein synthesis in controlling dendritic spine formation and suggest a potential etiology of neurodegenerative disorders caused by mutations in VCP, ATL1 and other genes encoding proteins regulating ER formation and morphogenesis.


Assuntos
Retículo Endoplasmático/metabolismo , Proteínas de Ligação ao GTP/genética , Proteínas de Membrana/genética , Doenças do Sistema Nervoso/genética , Proteína com Valosina/genética , Proteínas de Ligação ao GTP/metabolismo , Humanos , Proteínas de Membrana/metabolismo , Doenças do Sistema Nervoso/fisiopatologia , Biossíntese de Proteínas , Proteína com Valosina/metabolismo
3.
Neural Plast ; 2016: 5136286, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26819769

RESUMO

Dendritic spines are the location of excitatory synapses in the mammalian nervous system and are neuron-specific subcellular structures essential for neural circuitry and function. Dendritic spine morphology is determined by the F-actin cytoskeleton. F-actin remodeling must coordinate with different stages of dendritic spinogenesis, starting from dendritic filopodia formation to the filopodia-spines transition and dendritic spine maturation and maintenance. Hundreds of genes, including F-actin cytoskeleton regulators, membrane proteins, adaptor proteins, and signaling molecules, are known to be involved in regulating synapse formation. Many of these genes are not neuron-specific, but how they specifically control dendritic spine formation in neurons is an intriguing question. Here, we summarize how ubiquitously expressed genes, including syndecan-2, NF1 (encoding neurofibromin protein), VCP, and CASK, and the neuron-specific gene CTTNBP2 coordinate with neurotransmission, transsynaptic signaling, and cytoskeleton rearrangement to control dendritic filopodia formation, filopodia-spines transition, and dendritic spine maturation and maintenance. The aforementioned genes have been associated with neurological disorders, such as autism spectrum disorders (ASDs), mental retardation, learning difficulty, and frontotemporal dementia. We also summarize the corresponding disorders in this report.


Assuntos
Dendritos/metabolismo , Espinhas Dendríticas/metabolismo , Doenças do Sistema Nervoso/metabolismo , Neurogênese/fisiologia , Neurônios/metabolismo , Transdução de Sinais/fisiologia , Actinas/metabolismo , Animais , Humanos , Sinapses/metabolismo
4.
bioRxiv ; 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36778241

RESUMO

Heterozygous mutations in the Dual specificity tyrosine-phosphorylation-regulated kinase 1a Dyrk1a gene define a syndromic form of Autism Spectrum Disorder. The synaptic and circuit mechanisms mediating Dyrk1a functions in social cognition are unclear. Here, we identify a social experience-sensitive mechanism in hippocampal mossy fiber-parvalbumin interneuron (PV IN) synapses by which Dyrk1a recruits feedforward inhibition of CA3 and CA2 to promote social recognition. We employ genetic epistasis logic to identify a cytoskeletal protein, Ablim3, as a synaptic substrate of Dyrk1a. We demonstrate that Ablim3 downregulation in dentate granule cells of adult hemizygous Dyrk1a mice is sufficient to restore PV IN mediated inhibition of CA3 and CA2 and social recognition. Acute chemogenetic activation of PV INs in CA3/CA2 of adult hemizygous Dyrk1a mice also rescued social recognition. Together, these findings illustrate how targeting Dyrk1a synaptic and circuit substrates as "enhancers of Dyrk1a function" harbors potential to reverse Dyrk1a haploinsufficiency-associated circuit and cognition impairments. Highlights: Dyrk1a in mossy fibers recruits PV IN mediated feed-forward inhibition of CA3 and CA2Dyrk1a-Ablim3 signaling in mossy fiber-PV IN synapses promotes inhibition of CA3 and CA2 Downregulating Ablim3 restores PV IN excitability, CA3/CA2 inhibition and social recognition in Dyrk1a+/- mice Chemogenetic activation of PV INs in CA3/CA2 rescues social recognition in Dyrk1a+/- mice.

5.
Neuron ; 111(19): 3084-3101.e5, 2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37797581

RESUMO

Heterozygous mutations in the dual-specificity tyrosine phosphorylation-regulated kinase 1a (Dyrk1a) gene define a syndromic form of autism spectrum disorder. The synaptic and circuit mechanisms mediating DYRK1A functions in social cognition are unclear. Here, we identify a social experience-sensitive mechanism in hippocampal mossy fiber-parvalbumin interneuron (PV IN) synapses by which DYRK1A recruits feedforward inhibition of CA3 and CA2 to promote social recognition. We employ genetic epistasis logic to identify a cytoskeletal protein, ABLIM3, as a synaptic substrate of DYRK1A. We demonstrate that Ablim3 downregulation in dentate granule cells of adult heterozygous Dyrk1a mice is sufficient to restore PV IN-mediated inhibition of CA3 and CA2 and social recognition. Acute chemogenetic activation of PV INs in CA3/CA2 of adult heterozygous Dyrk1a mice also rescued social recognition. Together, these findings illustrate how targeting DYRK1A synaptic and circuit substrates as "enhancers of DYRK1A function" harbors the potential to reverse Dyrk1a haploinsufficiency-associated circuit and cognition impairments.


Assuntos
Transtorno do Espectro Autista , Animais , Camundongos , Encéfalo , Fibras Musgosas Hipocampais/fisiologia , Parvalbuminas , Reconhecimento Psicológico , Sinapses/fisiologia , Quinases Dyrk
6.
Artigo em Inglês | MEDLINE | ID: mdl-22474505

RESUMO

San-Huang-Xie-Xin-Tang (SHXT), composed of Coptidis rhizoma, Scutellariae radix, and Rhei rhizoma, is a traditional Chinese medicine used for complementary and alternative therapy of cardiovascular and neurodegenerative diseases via its anti-inflammatory and antioxidative effects. The aim of this study is to investigate the protective effects of SHXT in the 1-methyl-4-phenylpyridinium (MPP(+))/1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) models of Parkinson's disease. Rat primary mesencephalic neurons and mouse Parkinson disease model were used in this study. Oxidative stress was induced by MPP(+) in vitro and MPTP in vivo. In MPP(+)-treated mesencephalic neuron cultures, SHXT significantly increased the numbers of TH-positive neurons. SHXT reduced apoptotic signals (cytochrome and caspase) and apoptotic death. MPP(+)-induced gp91(phox) activation and ROS production were attenuated by SHXT. In addition, SHXT increased the levels of GSH and SOD in MPP(+)-treated neurons. In MPTP animal model, SHXT markedly increased TH-positive neurons in the substantia nigra pars compacta (SNpc) and improved motor activity of mice. In conclusion, the present results reveal the evidence that SHXT possesses beneficial protection against MPTP-induced neurotoxicity in this model of Parkinson's disease via its antioxidative and antiapoptotic effects. SHXT might be a potentially alternative and complementary medicine for neuroprotection.

7.
Elife ; 112022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34982030

RESUMO

Experience governs neurogenesis from radial-glial neural stem cells (RGLs) in the adult hippocampus to support memory. Transcription factors (TFs) in RGLs integrate physiological signals to dictate self-renewal division mode. Whereas asymmetric RGL divisions drive neurogenesis during favorable conditions, symmetric divisions prevent premature neurogenesis while amplifying RGLs to anticipate future neurogenic demands. The identities of TFs regulating RGL symmetric self-renewal, unlike those that regulate RGL asymmetric self-renewal, are not known. Here, we show in mice that the TF Kruppel-like factor 9 (Klf9) is elevated in quiescent RGLs and inducible, deletion of Klf9 promotes RGL activation state. Clonal analysis and longitudinal intravital two-photon imaging directly demonstrate that Klf9 functions as a brake on RGL symmetric self-renewal. In vivo translational profiling of RGLs lacking Klf9 generated a molecular blueprint for RGL symmetric self-renewal that was characterized by upregulation of genetic programs underlying Notch and mitogen signaling, cell cycle, fatty acid oxidation, and lipogenesis. Together, these observations identify Klf9 as a transcriptional regulator of neural stem cell expansion in the adult hippocampus.


In humans and other mammals, a region of the brain known as the hippocampus plays important roles in memory. New experiences guide cells in the hippocampus known as radial-glial neural stem cells (RGLs) to divide to make new neurons and other types of cells involved in forming memories. Each time an RGL divides, it can choose to divide asymmetrically to maintain a copy of itself and make a new cell of another type, or divide symmetrically (a process known as symmetric self-renewal) to produce two RGLs. Symmetric self-renewal helps to restore and replenish the pool of stem cells in the hippocampus that are lost due to injury or age, allowing us to continue making new neurons. Proteins known as transcription factors are believed to control how RGLs divide. Previous studies have identified several transcription factors that regulate the RGLs splitting asymmetrically to make neurons and other cells. But the identities of the transcription factors that regulate symmetric self-renewal in the adult hippocampus have remained elusive. Here, Guo et al. searched for transcription factors that regulate symmetric self-renewal of RGLs in mice. The experiments found that RGLs that are resting and not dividing (referred to as 'quiescent') have higher levels of a transcription factor called Klf9 than RGLs that are actively dividing. Loss of the gene encoding Klf9 triggered quiescent RGLs to start dividing, and further experiments showed that Klf9 directly inhibited symmetric self-renewal. Guo et al. then used an approach called in vivo translational profiling to generate a blueprint that revealed new insights into the molecular processes involved in this symmetric division. These findings pave the way for researchers to develop strategies that may expand the numbers of stem cells in the hippocampus. This could eventually be used to help replenish brain circuits with neurons and improve the memory of individuals with Alzheimer's disease or other conditions that cause memory loss.


Assuntos
Proliferação de Células , Hipocampo/fisiologia , Células-Tronco Neurais/fisiologia , Transcrição Gênica , Animais , Crescimento Celular , Feminino , Masculino , Ratos
8.
Artigo em Inglês | MEDLINE | ID: mdl-19339484

RESUMO

San-Huang-Xie-Xin-Tang (SHXT), composed of Coptidis rhizoma, Scutellariae radix and Rhei rhizoma, is a traditional Chinese herbal medicine used to treat gastritis, gastric bleeding and peptic ulcers. This study investigated the neuroprotective effects of SHXT on microglia-mediated neurotoxicity using co-cultured lipopolysaccharide (LPS)-activated microglia-like BV-2 cells with neuroblastoma SH-SY5Y cells. Effects of SHXT on 6-hydroxydopamine (6-OHDA)-induced neurotoxicity were also examined in SH-SY5Y cells. Results indicated SHXT inhibited LPS-induced inflammation of BV-2 cells by downregulation of iNOS, NO, COX-2, PGE(2), gp91(phox), iROS, TNF-α, IL-1ß, inhibition of IκBα degradation and upregulation of HO-1. In addition, SHXT increased cell viability and down regulated nNOS, COX-2 and gp91(phox) of SH-SY5Y cells co-cultured with LPS activated BV-2 cells. SHXT treatment increased cell viability and mitochondria membrane potential (MMP), decreased expression of nNOS, COX-2, gp91(phox) and iROS, and inhibited IκBα degradation in 6-OHDA-treated SH-SY5Y cells. SHXT also attenuated LPS activated BV-2 cells- and 6-OHDA-induced cell death in differentiated SH-SY5Y cells with db-cAMP. Furthermore, SHXT-inhibited nuclear translocation of p65 subunit of NF-κB in LPS treated BV-2 cells and 6-OHDA treated SH-SY5Y cells. In conclusion, SHXT showed protection from activated microglia- and 6-OHDA-induced neurotoxicity by attenuating inflammation and oxidative stress.

9.
iScience ; 24(1): 101949, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33437936

RESUMO

Both genetic variations and nutritional deficiency are associated with autism spectrum disorders and other neurological disorders. However, it is less clear whether or how nutritional deficiency and genetic variations influence each other under pathogenic conditions. "Valosin-containing protein" (VCP, also known as p97) is associated with multiple neurological disorders and regulates dendritic spine formation by controlling endoplasmic reticulum formation and protein synthesis efficiency. Increased protein synthesis ameliorates the dendritic spine defects of Vcp-deficient neurons. Therefore, we investigated if Vcp-deficient mice are sensitive to nutritional conditions. Here, we show that social interaction and contextual memory of Vcp-deficient mice are indeed influenced by different dietary protein levels. Moreover, leucine supplementation ameliorates the behavioral deficits and dendritic spine density of Vcp-deficient mice, strengthening evidence for the role of protein synthesis in VCP function. Our study illustrates that genetic variation and nutrient factors cross-talk to influence neuronal and behavioral phenotypes.

10.
Virol J ; 7: 214, 2010 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-20819232

RESUMO

BACKGROUND: Dengue virus, a mosquito-borne flavivirus, is the etiological agent of dengue fever, dengue hemorrhagic fever, and dengue shock syndrome. It generally induces apoptosis in mammalian cells, but frequently results in persistent infection in mosquito cells. That mechanism remains to be explored. In turn, a genomic survey through subtractive hybridization (PCR-select cDNA subtraction) was conducted in order to find gene(s) that may play a role in interactions between the virus and its host cells. RESULTS: Through this technique, we identified a novel eukaryotic translation initiation factor 5A (eIF5A) which is upregulated in Aedes albopictus-derived C6/36 cells infected by the type 2 dengue (Den-2) virus. The full-length of the identified eIF5A gene consisted of 1498 bp of nucleotides with a 41.39% G+C content, and it possessed a higher similarity and shorter evolutionary distance with insects than with other organisms. Upregulation of eIF5A in response to Den-2 virus infection was validated at both the RNA and protein levels. This phenomenon was also observed by confocal microscopy. In addition, cell death obviously occurred when eIF5A activity was inhibited in C6/36 cells even when they were infected by the virus. However, viral multiplication was not obviously affected in infected C6/36 cells when eIF5A activity was reduced. CONCLUSIONS: Taken together, we postulated that eIF5A plays a role in preventing mosquito cells from death in response to Den-2 viral infection, thus facilitating continued viral growth and potential persistent infection in mosquito cells. It would be worthwhile to further investigate how its downstream factors or cofactors contribute to this phenomenon of dengue infection.


Assuntos
Aedes/virologia , Vírus da Dengue/crescimento & desenvolvimento , Interações Hospedeiro-Patógeno , Proteínas de Insetos/biossíntese , Fatores de Iniciação de Peptídeos/biossíntese , Proteínas de Ligação a RNA/biossíntese , Animais , Composição de Bases , Morte Celular , Linhagem Celular , Perfilação da Expressão Gênica , Proteínas de Insetos/genética , Microscopia Confocal , Dados de Sequência Molecular , Fatores de Iniciação de Peptídeos/genética , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Regulação para Cima , Fator de Iniciação de Tradução Eucariótico 5A
11.
Planta Med ; 76(2): 120-7, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19653144

RESUMO

Polyalthia longifolia var. pendula is used as an antipyretic agent in indigenous systems of medicine. Microglia-mediated inflammation plays an important role in the pathway leading to neuronal cell death in a number of neurodegenerative diseases. The aim of this study was to investigate the effects of 6-hydroxycleroda-3,13-dien-15,16-olide (PL3) extracted from Polyalthia longifolia var. pendula on lipopolysaccharide(LPS)-induced inflammation in microglia-like HAPI cells and primary microglia cultures. In microglia-neuron co-cultures, LPS decreased the cell viability of neuroblastoma SH-SY5Y cells. LPS-induced cell death was attenuated by the NOS inhibitor, L-NAME, the COX-2 inhibitor, NS-398 or the NADPH oxidase inhibitor, DPI, respectively. In LPS-treated microglia cells, PL3 decreased the expression of iNOS, COX-2, gp91 (phox), and NF- kappaBp65, the degradation of I kappaB alpha, and the production of NO, PGE (2), iROS, and TNF- alpha. PL3 also enhanced the expression of HO-1, a cytoprotective and anti-inflammatory enzyme. Moreover, PL3 reduced LPS-activated microglia-induced cell death. The present results suggest that PL3 inhibits microglia-mediated inflammation and inflammation-related neuronal cell death. Therefore, PL3 has potential use for the treatment of inflammation-related neurodegenerative diseases.


Assuntos
Morte Celular/efeitos dos fármacos , Diterpenos/uso terapêutico , Inflamação/prevenção & controle , Neurônios/efeitos dos fármacos , Síndromes Neurotóxicas/prevenção & controle , Extratos Vegetais/uso terapêutico , Polyalthia/química , Animais , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Linhagem Celular Tumoral , Diterpenos/isolamento & purificação , Diterpenos/farmacologia , Inibidores Enzimáticos/farmacologia , Humanos , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos , Microglia/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Ratos , Ratos Sprague-Dawley
12.
Cell Rep ; 31(13): 107835, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32610136

RESUMO

Neurofibromatosis type 1 (NF1) is a dominant genetic disorder manifesting, in part, as cognitive defects. Previous study indicated that neurofibromin (NF1 protein) interacts with valosin-containing protein (VCP)/P97 to control dendritic spine formation, but the mechanism is unknown. Here, using Nf1+/- mice and transgenic mice overexpressing wild-type Vcp/p97, we demonstrate that neurofibromin acts with VCP to control endoplasmic reticulum (ER) formation and consequent protein synthesis and regulates dendritic spine formation, thereby modulating contextual fear memory and social interaction. To validate the role of protein synthesis, we perform leucine supplementation in vitro and in vivo. Our results suggest that leucine can effectively enter the brain and increase protein synthesis and dendritic spine density of Nf1+/- neurons. Contextual memory and social behavior of Nf1+/- mice are also restored by leucine supplementation. Our study suggests that the "ER-protein synthesis" pathway downstream of neurofibromin and VCP is a critical regulator of dendritic spinogenesis and brain function.


Assuntos
Medo/fisiologia , Leucina/administração & dosagem , Memória/fisiologia , Neurofibromina 1/metabolismo , Biossíntese de Proteínas , Comportamento Social , Proteína com Valosina/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , Células Cultivadas , Espinhas Dendríticas/metabolismo , Espinhas Dendríticas/ultraestrutura , Suplementos Nutricionais , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Retículo Endoplasmático/ultraestrutura , Camundongos Mutantes , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Biossíntese de Proteínas/efeitos dos fármacos , Proteoma/metabolismo , Sirolimo/farmacologia , Sinapses/efeitos dos fármacos , Sinapses/metabolismo
13.
Inflamm Res ; 58(6): 329-35, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19247579

RESUMO

OBJECTIVE: To investigate the in vitro effects of H. pylori-conditioned medium (HCM) from gastric epithelial AGS cell cultures on microglia and neuronal cells. MATERIAL: H. pylori, human gastric epithelial AGS cells, microglia-like BV-2 cells and human neuroblastoma SH-SY5Y cells. TREATMENT: Treated AGS cells with H. pylori at ratios from 1:100 to 1:900 for 24 h. Cultured BV-2 cells and SH-SY5Y cells were treated with HCM from AGS cell cultures. METHODS: Cell viability was measured by a quantitative colorimetric assay with MTT. Nitric oxide (NO) was determined by using Griess reagent. IL-8 was measured by an enzyme-linked immunosorbent assay. Protein expressions were revealed by western blot analysis. RESULTS: H. pylori increased IL-8, NO, COX-2 and gp91(phox) in AGS cell cultures. When BV-2 cells were cocultured with AGS cells, HCM increased COX-2, gp91(phox), iNOS and NO of BV-2 cells. HCM also enhanced the degradation of I kappaB alpha in BV-2 cells. HCM up-regulated expression of nNOS, COX-2, and gp91(phox) of SH-SY5Y cells co-cultured with BV-2 cells. Particularly, the decrease of cell viability of SH-SY5Y induced by HCM was dependent on the presence of BV-2 cells. CONCLUSIONS: H. pylori-induced infection induces microglia-mediated inflammation and neurotoxicity. The present results suggest that microglia play a critical role in HCM-induced toxicity of neuronal SH-SY5Y cells.


Assuntos
Mucosa Gástrica/imunologia , Helicobacter pylori/fisiologia , Microglia/imunologia , Linhagem Celular , Sobrevivência Celular , Meios de Cultivo Condicionados , Ciclo-Oxigenase 2/metabolismo , Células Epiteliais/imunologia , Mucosa Gástrica/microbiologia , Helicobacter pylori/imunologia , Humanos , Interleucina-8/metabolismo , Glicoproteínas de Membrana/metabolismo , Microglia/citologia , NADPH Oxidase 2 , NADPH Oxidases/metabolismo , Neurônios/citologia , Neurônios/imunologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo
14.
Bioorg Med Chem ; 16(10): 5803-14, 2008 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-18407506

RESUMO

Fifty-two 2-benzoylaminobenzoate analogs were synthesized and subjected to anti-platelet aggregation assay using arachidonic acid (AA), collagen (Col), thrombin (Thr), and U46619 as inducers. The results revealed that most of 2-benzoylaminobenzoic acid derivatives showed a selectively inhibitory effect on AA-induced platelet aggregation. As a result of the 2-benzoylaminobenzoic acid derivatives (18, 44, and 46), there were no inhibitory effects on platelet aggregation induced by U46619, but these elicited an inhibitory effect on thromboxane B(2) formation at 1.0microM. These 2-benzoylaminobenzoate analogs were therefore proposed as cyclooxygenase inhibitors.


Assuntos
Aminobenzoatos/síntese química , Aminobenzoatos/farmacologia , Inibidores da Agregação Plaquetária/síntese química , Inibidores da Agregação Plaquetária/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Aminobenzoatos/química , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Inibidores da Agregação Plaquetária/química , Estereoisomerismo , Relação Estrutura-Atividade
15.
eNeuro ; 5(6)2018.
Artigo em Inglês | MEDLINE | ID: mdl-30783609

RESUMO

While PTEN-induced kinase 1 (PINK1) is well characterized for its role in mitochondrial homeostasis, much less is known concerning its ability to prevent synaptodendritic degeneration. Using unbiased proteomic methods, we identified valosin-containing protein (VCP) as a major PINK1-interacting protein. RNAi studies demonstrate that both VCP and its cofactor NSFL1C/p47 are necessary for the ability of PINK1 to increase dendritic complexity. Moreover, PINK1 regulates phosphorylation of p47, but not the VCP co-factor UFD1. Although neither VCP nor p47 interact directly with PKA, we found that PINK1 binds and phosphorylates the catalytic subunit of PKA at T197 [PKAcat(pT197)], a site known to activate the PKA holoenzyme. PKA in turn phosphorylates p47 at a novel site (S176) to regulate dendritic complexity. Given that PINK1 physically interacts with both the PKA holoenzyme and the VCP-p47 complex to promote dendritic arborization, we propose that PINK1 scaffolds a novel PINK1-VCP-PKA-p47 signaling pathway to orchestrate dendritogenesis in neurons. These findings highlight an important mechanism by which proteins genetically implicated in Parkinson's disease (PD; PINK1) and frontotemporal dementia (FTD; VCP) interact to support the health and maintenance of neuronal arbors.


Assuntos
Plasticidade Neuronal/fisiologia , Neurônios/fisiologia , Proteínas Quinases/metabolismo , Animais , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Ativação Enzimática/fisiologia , Demência Frontotemporal/metabolismo , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Doença de Parkinson/metabolismo , Fosforilação , Ratos , Ratos Sprague-Dawley , Proteínas de Ligação a Fator Solúvel Sensível a N-Etilmaleimida/metabolismo , Proteína com Valosina/metabolismo
16.
Virus Res ; 124(1-2): 176-83, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17156880

RESUMO

Dengue (Den) viruses cause apoptosis in mammalian cells, but usually result in high progeny yields without evident damage in mosquito cells. By using subtractive hybridization, 13 potentially virus-induced genes were selected in Den-2 virus-infected Aedes albopictus C6/36 cells. Based on semi-quantitative and real-time RT-PCR, one novel gene, named C189, was significantly upregulated in infected C6/36 cells. Its full-length of 678 nucleotides (nt) was determined by a combination of 5'- and 3'-RACE products. After alignment, C189 was classified as a member of the tetraspanin superfamily that typically has 2 short cytoplasmic sequences, 4 transmembrane domains, as well as small and large extracellular regions (EC1 and EC2). It contains the hallmark CCG motif in the EC2 region and additional 17 conserved nucleotides as do other tetraspanins. C189 was not upregulated by inoculation of UV-inactivated Den-2 virus to C6/36 cells. This suggests that tetraspanin upregulation is not related to virus binding to the cell surface, and that C189 does not function as a receptor for dengue virus entry. On the other hand, overexpression of C189 was concurrent with viral proteins, targeting the plasma membrane of C6/36 cells infected with Den-2 virus. It is presumably beneficial or essential for cell-to-cell spread of the virus due to the role of tetraspanins demonstrated in intercellular adhesion.


Assuntos
Vírus da Dengue/crescimento & desenvolvimento , Proteínas de Membrana/biossíntese , Aedes/química , Aedes/genética , Aedes/virologia , Sequência de Aminoácidos , Animais , Linhagem Celular , Membrana Celular/química , Sequência Conservada , Regulação da Expressão Gênica , Proteínas de Membrana/genética , Microscopia Confocal , Dados de Sequência Molecular , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Análise de Sequência de DNA
17.
J Ethnopharmacol ; 112(3): 537-44, 2007 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-17537603

RESUMO

Helicobacter pylori infection leads to gastroduodenal inflammation, peptic ulceration, gastric lymphoma and gastric cancer. Certain herbal remedies have been used to treat gastric disease. In this study, we examined the anti-inflammatory effect of San-Huang-Xie-Xin-Tang (SHXT) and its main component baicalin on Helicobacter pylori-infected human gastric epithelial AGS cell. AGS cells were treated with Helicobacter pylori at a bacterium/cell ratio of 300:1. mRNA expression and protein levels were determined by reverse transcriptase-polymerase chain reaction (RT-PCR) analysis and western blot analysis, respectively. Interleukin-8 (IL-8) level and the translocation of nuclear factor kappa B (NF-kappaB) were measured by enzyme-linked immunosorbent assay (ELISA) and enzyme-linked DNA-protein interaction assay (ELDIA), respectively. Nitric oxide production was measured by Griess reagent. We found that SHXT and baicalin inhibited Helicobacter pylori-induced cyclooxygenase-2 (COX-2) enhancement and IkappaBalpha degradation in both mRNA and protein levels. SHXT and baicalin also inhibited Helicobacter pylori-induced inducible nitric oxide synthase (iNOS) and IL-8 mRNA expression, and decreased NO and IL-8 production. Furthermore, SHXT and baicalin inhibited nuclear translocation of p50 subunit of NF-kappaB in Helicobacter pylori-infected AGS cells. Based on the above findings, SHXT and baicalin might exert anti-inflammatory and gastroprotective effects in Helicobacter pylori-induced gastric inflammation.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Células Epiteliais/efeitos dos fármacos , Helicobacter pylori/efeitos dos fármacos , Western Blotting , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Flavonoides/química , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/microbiologia , Mucosa Gástrica/patologia , Helicobacter pylori/crescimento & desenvolvimento , Humanos , Proteínas I-kappa B/genética , Proteínas I-kappa B/metabolismo , Inflamação/microbiologia , Inflamação/patologia , Inflamação/prevenção & controle , Interleucina-8/genética , Interleucina-8/metabolismo , Testes de Sensibilidade Microbiana , Subunidade p50 de NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Transporte Proteico/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
Nat Commun ; 7: 11020, 2016 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-26984393

RESUMO

Imbalanced protein homeostasis, such as excessive protein synthesis and protein aggregation, is a pathogenic hallmark of a range of neurological disorders. Here, using expression of mutant proteins, a knockdown approach and disease mutation knockin mice, we show that VCP (valosin-containing protein), together with its cofactor P47 and the endoplasmic reticulum (ER) morphology regulator ATL1 (Atlastin-1), regulates tubular ER formation and influences the efficiency of protein synthesis to control dendritic spine formation in neurons. Strengthening the significance of protein synthesis in dendritic spinogenesis, the translation blocker cyclohexamide and the mTOR inhibitor rapamycin reduce dendritic spine density, while a leucine supplement that increases protein synthesis ameliorates the dendritic spine defects caused by Vcp and Atl1 deficiencies. Because VCP and ATL1 are the causative genes of several neurodegenerative and neurodevelopmental disorders, we suggest that impaired ER formation and inefficient protein synthesis are significant in the pathogenesis of multiple neurological disorders.


Assuntos
Adenosina Trifosfatases/metabolismo , Proteínas de Ciclo Celular/metabolismo , Espinhas Dendríticas/metabolismo , Retículo Endoplasmático/metabolismo , Proteínas de Membrana/metabolismo , Biossíntese de Proteínas , Animais , Cicloeximida/farmacologia , Espinhas Dendríticas/efeitos dos fármacos , Retículo Endoplasmático/efeitos dos fármacos , Técnicas de Introdução de Genes , Técnicas de Silenciamento de Genes , Peptídeos e Proteínas de Sinalização Intercelular , Peptídeos e Proteínas de Sinalização Intracelular , Canais Iônicos/metabolismo , Leucina/farmacologia , Camundongos , Mutação/genética , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/ultraestrutura , Biossíntese de Proteínas/efeitos dos fármacos , Proteínas/metabolismo , Proteólise/efeitos dos fármacos , Ratos , Sirolimo/farmacologia , Proteínas de Ligação a Fator Solúvel Sensível a N-Etilmaleimida/metabolismo , Sinapses/efeitos dos fármacos , Sinapses/metabolismo , Proteína com Valosina , Proteínas rab de Ligação ao GTP/metabolismo
19.
Shock ; 37(3): 312-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22089194

RESUMO

Inflammation and oxidative stress play important roles in the pathogenesis of neurodegenerative disorders such as stroke, traumatic injury, Parkinson disease, and Alzheimer disease. Paeonol, a natural compound extracted from Moutan cortex, is a potent anti-inflammatory and antioxidative agent. The aim of this study was to investigate the neuroprotective mechanisms of paeonol on lipopolysaccharide (LPS)-induced inflammation in rat primary microglia and 6-hydroxydopamine-induced oxidative damage in cortical neurons. In LPS-treated microglia, paeonol attenuated the overexpression of inducible nitric oxide synthase and cyclooxygenase 2, leading to the decrease in nitric oxide and prostaglandin E2 production, respectively. Paeonol also suppressed LPS-induced phosphorylation of extracellular signal-regulated kinase and Jun N-terminal kinase. In addition, LPS-stimulated NADPH oxidase activation and reactive oxygen species production were attenuated by paeonol. Paeonol-induced upregulation of heme oxygenase 1 was also observed. Moreover, paeonol attenuated LPS-treated microglia culture medium-induced neuron cells death. Posttreatment with paeonol also reduced inflammatory responses in LPS-activated microglia and increased cell viability in LPS-treated microglia culture medium-treated neurons. Furthermore, in 6-hydroxydopamine-treated cortical neurons, paeonol not only decreased reactive oxygen species production but also increased cell viability, superoxide dismutase activity, and the antiapoptotic protein B-cell lymphoma 2 expression. Taken together, the present results suggest that paeonol might be a potential neuroprotective agent via inhibiting microglia-mediated inflammation and oxidative stress-induced neuronal damage.


Assuntos
Acetofenonas/farmacologia , Anti-Inflamatórios/farmacologia , Inflamação/prevenção & controle , Microglia/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Córtex Cerebral/citologia , Ciclo-Oxigenase 2/metabolismo , Feminino , Heme Oxigenase-1/biossíntese , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/antagonistas & inibidores , Microglia/fisiologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Doenças Neurodegenerativas/prevenção & controle , Neurônios/metabolismo , Óxido Nítrico Sintase Tipo II/biossíntese , Oxidopamina/farmacologia , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/antagonistas & inibidores
20.
J Clin Invest ; 121(12): 4820-37, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22105171

RESUMO

Inclusion body myopathy with Paget disease of bone and frontotemporal dementia (IBMPFD) is an autosomal dominant disorder characterized by progressive myopathy that is often accompanied by bone weakening and/or frontotemporal dementia. Although it is known to be caused by mutations in the gene encoding valosin-containing protein (VCP), the underlying disease mechanism remains elusive. Like IBMPFD, neurofibromatosis type 1 (NF1) is an autosomal dominant disorder. Neurofibromin, the protein encoded by the NF1 gene, has been shown to regulate synaptogenesis. Here, we show that neurofibromin and VCP interact and work together to control the density of dendritic spines. Certain mutations identified in IBMPFD and NF1 patients reduced the interaction between VCP and neurofibromin and impaired spinogenesis. The functions of neurofibromin and VCP in spinogenesis were shown to correlate with the learning disability and dementia phenotypes seen in patients with IBMPFD. Consistent with the previous finding that treatment with a statin rescues behavioral defects in Nf1(+/-) mice and providing further support for our hypothesis that there is crosstalk between neurofibromin and VCP, statin exposure neutralized the effect of VCP knockdown on spinogenesis in cultured hippocampal neurons. The data presented here demonstrate that there is a link between IBMPFD and NF1 and indicate a role for VCP in synapse formation.


Assuntos
Adenosina Trifosfatases/fisiologia , Proteínas de Ciclo Celular/fisiologia , Contratura/congênito , Dendritos/ultraestrutura , Demência Frontotemporal/genética , Miosite de Corpos de Inclusão/congênito , Neurofibromatose 1/genética , Neurofibromina 1/fisiologia , Oftalmoplegia/genética , Osteíte Deformante/genética , Animais , Região CA1 Hipocampal/ultraestrutura , Células Cultivadas/efeitos dos fármacos , Células Cultivadas/ultraestrutura , Colesterol/fisiologia , Contratura/genética , Contratura/patologia , Dendritos/metabolismo , Demência Frontotemporal/patologia , Humanos , Deficiências da Aprendizagem/tratamento farmacológico , Deficiências da Aprendizagem/genética , Lovastatina/farmacologia , Lovastatina/uso terapêutico , Camundongos , Camundongos Knockout , Mutação de Sentido Incorreto , Miosite de Corpos de Inclusão/genética , Miosite de Corpos de Inclusão/patologia , Neurofibromatose 1/patologia , Neurofibromatose 1/psicologia , Neurofibromina 1/deficiência , Neurofibromina 1/genética , Oftalmoplegia/patologia , Osteíte Deformante/patologia , Mutação Puntual , Mapeamento de Interação de Proteínas , Estrutura Terciária de Proteína , Células Piramidais/efeitos dos fármacos , Células Piramidais/ultraestrutura , Ratos , Sinapses/ultraestrutura , Proteína com Valosina
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