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The assembly of heterometallic cluster substituted polyoxometalates (POMs) remains a great challenge for inorganic synthetic chemistry up to now. Herein, a series of 5p-4f heterometallic cluster substituted POMs were successfully isolated by a facile one-step hydrothermal reaction method, namely H17(H2en)3[SbIII9SbVLn3O14(H2O)3][(SbW9O33)3(PW9O34)]·28H2O(1-Ln, Ln = Ce, Sm, Eu, Gd, Tb, Dy) (en = ethylenediamine). Interestingly, by replacing en with imidazole, another series of 5p-4f heterometallic cluster substituted POMs H13(HIm)4K2Na4(H2O)9[SbIII9SbVLn3O14(H2O)3][(SbW9O33)3(PW9O34)]·26H2O (2-Ln, Ln = Sm, Eu, Gd, Tb, Dy, Im = imidazole) were obtained. Structural analyses indicate that both 1-Ln and 2-Ln are made up of an unprecedented 5p-4f heterometallic {Sb10Ln3O14(H2O)3} cluster stabilized simultaneously by mixed trilacunary heteropolyanions including {A-α-PW9O34} and {B-α-SbW9O33}. Impedance measurements indicate that both compounds exhibit different proton conduction properties, and the conductivity of 2 can reach up to 1.64 × 10-2 S cm-1 at 85 °C under 98% relative humidity. Moreover, the fluorescence emission behaviors of both compounds have been studied.
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BACKGROUND: Identifying cancer biomarkers from transcriptomics data is of importance to cancer research. However, transcriptomics data are often complex and heterogeneous, which complicates the identification of cancer biomarkers in practice. Currently, the heterogeneity still remains a challenge for detecting subtle but consistent changes of gene expression in cancer cells. RESULTS: In this paper, we propose to adaptively capture the heterogeneity of expression across samples in a gene regulation space instead of in a gene expression space. Specifically, we transform gene expression profiles into gene regulation profiles and mathematically formulate gene regulation probabilities (GRPs)-based statistics for characterizing differential expression of genes between tumor and normal tissues. Finally, an unbiased estimator (aGRP) of GRPs is devised that can interrogate and adaptively capture the heterogeneity of gene expression. We also derived an asymptotical significance analysis procedure for the new statistic. Since no parameter needs to be preset, aGRP is easy and friendly to use for researchers without computer programming background. We evaluated the proposed method on both simulated data and real-world data and compared with previous methods. Experimental results demonstrated the superior performance of the proposed method in exploring the heterogeneity of expression for capturing subtle but consistent alterations of gene expression in cancer. CONCLUSIONS: Expression heterogeneity largely influences the performance of cancer biomarker identification from transcriptomics data. Models are needed that efficiently deal with the expression heterogeneity. The proposed method can be a standalone tool due to its capacity of adaptively capturing the sample heterogeneity and the simplicity in use. SOFTWARE AVAILABILITY: The source code of aGRP can be downloaded from https://github.com/hqwang126/aGRP .
Assuntos
Biomarcadores Tumorais/genética , Regulação Neoplásica da Expressão Gênica , Heterogeneidade Genética , Neoplasias/genética , Simulação por Computador , Perfilação da Expressão Gênica , Humanos , Modelos Genéticos , Análise de Sequência com Séries de Oligonucleotídeos , Probabilidade , Análise de Sequência de RNA , Software , TranscriptomaRESUMO
WHAT WE ALREADY KNOW ABOUT THIS TOPIC: WHAT THIS ARTICLE TELLS US THAT IS NEW: BACKGROUND:: Postoperative delirium is associated with poor long-term outcomes and increased mortality. General anesthetic drugs may contribute to delirium because they increase cell-surface expression and function of α5 subunit-containing γ-aminobutyric acid type A receptors, an effect that persists long after the drugs have been eliminated. Dexmedetomidine, an α2 adrenergic receptor agonist, prevents delirium in patients and reduces cognitive deficits in animals. Thus, it was postulated that dexmedetomidine prevents excessive function of α5 γ-aminobutyric acid type A receptors. METHODS: Injectable (etomidate) and inhaled (sevoflurane) anesthetic drugs were studied using cultured murine hippocampal neurons, cultured murine and human cortical astrocytes, and ex vivo murine hippocampal slices. γ-Aminobutyric acid type A receptor function and cell-signaling pathways were studied using electrophysiologic and biochemical methods. Memory and problem-solving behaviors were also studied. RESULTS: The etomidate-induced sustained increase in α5 γ-aminobutyric acid type A receptor cell-surface expression was reduced by dexmedetomidine (mean ± SD, etomidate: 146.4 ± 51.6% vs. etomidate + dexmedetomidine: 118.4 ± 39.1% of control, n = 8 each). Dexmedetomidine also reduced the persistent increase in tonic inhibitory current in hippocampal neurons (etomidate: 1.44 ± 0.33 pA/pF, n = 10; etomidate + dexmedetomidine: 1.01 ± 0.45 pA/pF, n = 9). Similarly, dexmedetomidine prevented a sevoflurane-induced increase in the tonic current. Dexmedetomidine stimulated astrocytes to release brain-derived neurotrophic factor, which acted as a paracrine factor to reduce excessive α5 γ-aminobutyric acid type A receptor function in neurons. Finally, dexmedetomidine attenuated memory and problem-solving deficits after anesthesia. CONCLUSIONS: Dexmedetomidine prevented excessive α5 γ-aminobutyric acid type A receptor function after anesthesia. This novel α2 adrenergic receptor- and brain-derived neurotrophic factor-dependent pathway may be targeted to prevent delirium.
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Anestésicos Intravenosos/farmacologia , Dexmedetomidina/farmacologia , Etomidato/farmacologia , Hipnóticos e Sedativos/farmacologia , Receptores de GABA-A/fisiologia , Agonistas de Receptores Adrenérgicos alfa 2/farmacologia , Animais , Células Cultivadas , Técnicas de Cocultura , Função Executiva/efeitos dos fármacos , Função Executiva/fisiologia , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Hipocampo/fisiologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
BACKGROUND: Large-scale accumulation of omics data poses a pressing challenge of integrative analysis of multiple data sets in bioinformatics. An open question of such integrative analysis is how to pinpoint consistent but subtle gene activity patterns across studies. Study heterogeneity needs to be addressed carefully for this goal. RESULTS: This paper proposes a regulation probability model-based meta-analysis, jGRP, for identifying differentially expressed genes (DEGs). The method integrates multiple transcriptomics data sets in a gene regulatory space instead of in a gene expression space, which makes it easy to capture and manage data heterogeneity across studies from different laboratories or platforms. Specifically, we transform gene expression profiles into a united gene regulation profile across studies by mathematically defining two gene regulation events between two conditions and estimating their occurring probabilities in a sample. Finally, a novel differential expression statistic is established based on the gene regulation profiles, realizing accurate and flexible identification of DEGs in gene regulation space. We evaluated the proposed method on simulation data and real-world cancer datasets and showed the effectiveness and efficiency of jGRP in identifying DEGs identification in the context of meta-analysis. CONCLUSIONS: Data heterogeneity largely influences the performance of meta-analysis of DEGs identification. Existing different meta-analysis methods were revealed to exhibit very different degrees of sensitivity to study heterogeneity. The proposed method, jGRP, can be a standalone tool due to its united framework and controllable way to deal with study heterogeneity.
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Biomarcadores Tumorais/metabolismo , Perfilação da Expressão Gênica , Modelos Estatísticos , Neoplasias/diagnóstico , Biomarcadores Tumorais/genética , Bases de Dados Genéticas , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Análise de Sequência com Séries de Oligonucleotídeos , RNA/química , RNA/metabolismo , Análise de Sequência de RNARESUMO
In Alzheimer's disease, accumulation of soluble oligomers of ß-amyloid peptide is known to be highly toxic, causing disturbances in synaptic activity and neuronal death. Multiple studies relate these effects to increased oxidative stress and aberrant activity of calcium-permeable cation channels leading to calcium imbalance. The transient receptor potential melastatin 2 (TRPM2) channel, a Ca(2+)-permeable nonselective cation channel activated by oxidative stress, has been implicated in neurodegenerative diseases, and more recently in amyloid-induced toxicity. Here we show that the function of TRPM2 is augmented by treatment of cultured neurons with ß-amyloid oligomers. Aged APP/PS1 Alzheimer's mouse model showed increased levels of endoplasmic reticulum stress markers, protein disulfide isomerase and phosphorylated eukaryotic initiation factor 2α, as well as decreased levels of the presynaptic marker synaptophysin. Elimination of TRPM2 in APP/PS1 mice corrected these abnormal responses without affecting plaque burden. These effects of TRPM2 seem to be selective for ß-amyloid toxicity, as ER stress responses to thapsigargin or tunicamycin in TRPM2(-/-) neurons was identical to that of wild-type neurons. Moreover, reduced microglial activation was observed in TRPM2(-/-)/APP/PS1 hippocampus compared with APP/PS1 mice. In addition, age-dependent spatial memory deficits in APP/PS1 mice were reversed in TRPM2(-/-)/APP/PS1 mice. These results reveal the importance of TRPM2 for ß-amyloid neuronal toxicity, suggesting that TRPM2 activity could be potentially targeted to improve outcomes in Alzheimer's disease. SIGNIFICANCE STATEMENT: Transient receptor potential melastatin 2 (TRPM2) is an oxidative stress sensing calcium-permeable channel that is thought to contribute to calcium dysregulation associated with neurodegenerative diseases, including Alzheimer's disease. Here we show that oligomeric ß-amyloid, the toxic peptide in Alzheimer's disease, facilitates TRPM2 channel activation. In mice designed to model Alzheimer's disease, genetic elimination of TRPM2 normalized deficits in synaptic markers in aged mice. Moreover, the absence of TRPM2 improved age-dependent spatial memory deficits observed in Alzheimer's mice. Our results reveal the importance of TRPM2 for neuronal toxicity and memory impairments in an Alzheimer's mouse model and suggest that TRPM2 could be targeted for the development of therapeutic agents effective in the treatment of dementia.
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Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Transtornos da Memória/metabolismo , Canais de Cátion TRPM/deficiência , Doença de Alzheimer/induzido quimicamente , Peptídeos beta-Amiloides/toxicidade , Animais , Células Cultivadas , Humanos , Masculino , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Placa Amiloide/metabolismo , Canais de Cátion TRPM/genéticaRESUMO
Metaplasticity is a higher form of synaptic plasticity that is essential for learning and memory, but its molecular mechanisms remain poorly understood. Here, we report that metaplasticity of transmission at CA1 synapses in the hippocampus is mediated by Src family kinase regulation of NMDA receptors (NMDARs). We found that stimulation of G-protein-coupled receptors (GPCRs) regulated the absolute contribution of GluN2A-versus GluN2B-containing NMDARs in CA1 neurons: pituitary adenylate cyclase activating peptide 1 receptors (PAC1Rs) selectively recruited Src kinase, phosphorylated GluN2ARs, and enhanced their functional contribution; dopamine 1 receptors (D1Rs) selectively stimulated Fyn kinase, phosphorylated GluN2BRs, and enhanced these currents. Surprisingly, PAC1R lowered the threshold for long-term potentiation while long-term depression was enhanced by D1R. We conclude that metaplasticity is gated by the activity of GPCRs, which selectively target subtypes of NMDARs via Src kinases.
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Receptores de N-Metil-D-Aspartato/metabolismo , Quinases da Família src/metabolismo , Animais , Western Blotting , Potenciais Pós-Sinápticos Excitadores , Hipocampo/metabolismo , Hipocampo/fisiologia , Imunoprecipitação , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Plasticidade Neuronal , Fosforilação , Ratos , Ratos WistarRESUMO
Synaptic plasticity refers to the ability of neurons to strengthen or weaken synaptic efficacy in response to activity and is the basis for learning and memory. Glial cells communicate with neurons and in this way contribute in part to plasticity in the CNS and to the pathology of Alzheimer's disease (AD), a neurodegenerative disease in which impaired synaptic plasticity is causally implicated. The transient receptor potential melastatin member 2 (TRPM2) channel is a nonselective Ca(2+)-permeable channel expressed in both glial cells (microglia and astrocytes) and neurons. Recent studies indicated that TRPM2 regulates synaptic plasticity as well as the activation of glial cells. TRPM2 also modulates oxidative stress and inflammation through interaction with glial cells. As both oxidative stress and inflammation have been implicated in AD pathology, this suggests a possible contribution of TRPM2 to disease processes. Through modulating the homeostasis of glutathione, TRPM2 is involved in the process of aging which is a risk factor of AD. These results potentially point TRPM2 channel to be involved in AD through glial cells. This review summarizes recent advances in studying the contribution of TRPM2 in health and in AD pathology, with a focus on contributions via glia cells.
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Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Neuroglia/metabolismo , Plasticidade Neuronal , Canais de Cátion TRPM/metabolismo , Animais , Humanos , Neurônios/metabolismo , Estresse OxidativoRESUMO
OBJECTIVE: Toll-like receptors (TLRs) pathway has been demonstrated to play an important role in periodontitis. However, the regulatory mechanism of microRNAs (miRNAs) on TLRs pathway is still unclear. Hence, this study is to explore the function of miRNA-146a in inflammatory reaction induced by Porphyromonas gingivalis lipopolysaccharide (LPS) in human periodontal ligament cells (hPDLCs). METHODS: Cells were treated with 1 or 10 µg/ml P. gingivalis LPS. The expression of TLR2, TLR4 and miRNA-146a were measured by real-time polymerase chain reaction (PCR). Enzyme-linked immunosorbent assay (ELISA) was applied to detect nuclear factor (NF)-κ B p65 nuclear activity, interleukin-1ß (IL-1ß), IL-6, IL-8 and tumor necrosis factor-α (TNF-α). To examine the underlying mechanisms, cells were exposed to anti-TLR2/4 mAb or miRNA-146a inhibitor/mimic and evaluated by real-time PCR and ELISA. RESULTS: 10 µg/ml P. gingivalis LPS increased the expressions of TLR2 (3.79 ± 0.31), TLR4 (2.21 ± 0.31), and miRNA-146a (4.91 ± 0.87), NF-κ B p65 nuclear activity (6.51 ± 0.77 fold) (p < 0.05). 1 µg/ml P. gingivalis LPS induced TLR2 (3.05 ± 0.23), miRNA-146a (3.66 ± 0.83) and NF-κ B p65 nuclear activity (4.06 ± 0.78 fold) (p < 0.05), except TLR4 (1.11 ± 0.30, p > 0.05). Also, cytokines production increased (p < 0.05). The up-regulation of miRNA-146a could be blocked by anti-TLR2/4 mAb (p < 0.05). After the blockage of miRNA-146a, TLR2, TLR4, NF-κ B p65 nuclear activity and proinflammatory cytokines increased. However, after application of miRNA-146a mimic, the levels of these indexes decreased obviously (p < 0.05). CONCLUSION: MiRNA-146a functions as a negative feedback regulator via down-regulating proinflammatory cytokine secretion and blocking TLRs signaling pathway in hPDLCs after P. gingivalis LPS stimulation.
Assuntos
Retroalimentação Fisiológica/fisiologia , Lipopolissacarídeos/farmacologia , MicroRNAs/genética , Ligamento Periodontal/efeitos dos fármacos , Porphyromonas gingivalis/química , Anticorpos Monoclonais/farmacologia , Células Cultivadas , Humanos , Lipopolissacarídeos/química , MicroRNAs/antagonistas & inibidores , NF-kappa B/efeitos dos fármacos , Ligamento Periodontal/patologia , Estimulação Química , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/genética , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/efeitos dos fármacosRESUMO
In Alzheimer's disease (AD), soluble amyloid-ß oligomers (AßOs) trigger neurotoxic signaling, at least partially, via the cellular prion protein (PrP(C)). However, it is unknown whether other ligands of PrP(C) can regulate this potentially toxic interaction. Stress-inducible phosphoprotein 1 (STI1), an Hsp90 cochaperone secreted by astrocytes, binds to PrP(C) in the vicinity of the AßO binding site to protect neurons against toxic stimuli. Here, we investigated a potential role of STI1 in AßO toxicity. We confirmed the specific binding of AßOs and STI1 to the PrP and showed that STI1 efficiently inhibited AßO binding to PrP in vitro (IC50 of â¼70 nm) and also decreased AßO binding to cultured mouse primary hippocampal neurons. Treatment with STI1 prevented AßO-induced synaptic loss and neuronal death in mouse cultured neurons and long-term potentiation inhibition in mouse hippocampal slices. Interestingly, STI1-haploinsufficient neurons were more sensitive to AßO-induced cell death and could be rescued by treatment with recombinant STI1. Noteworthy, both AßO binding to PrP(C) and PrP(C)-dependent AßO toxicity were inhibited by TPR2A, the PrP(C)-interacting domain of STI1. Additionally, PrP(C)-STI1 engagement activated α7 nicotinic acetylcholine receptors, which participated in neuroprotection against AßO-induced toxicity. We found an age-dependent upregulation of cortical STI1 in the APPswe/PS1dE9 mouse model of AD and in the brains of AD-affected individuals, suggesting a compensatory response. Our findings reveal a previously unrecognized role of the PrP(C) ligand STI1 in protecting neurons in AD and suggest a novel pathway that may help to offset AßO-induced toxicity.
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Peptídeos beta-Amiloides/metabolismo , Proteínas de Choque Térmico/metabolismo , Neurônios/metabolismo , Proteínas PrPC/metabolismo , Doença de Alzheimer/metabolismo , Animais , Astrócitos/metabolismo , Encéfalo/metabolismo , Células Cultivadas , Hipocampo/metabolismo , Camundongos , Ligação Proteica , Transdução de Sinais/fisiologia , Receptor Nicotínico de Acetilcolina alfa7/metabolismoRESUMO
Endocannabinoids (eCBs), including AEA and 2-AG, are endogenous signaling mediators involved in many physiological and pathological events. The G protein-coupled cannabinoid receptor 1 (CB1 R) is an important target for eCBs, however, additional non-CB1 receptor targets have also been identified. Although recent evidence suggests that NMDA receptor function may be regulated by eCBs, the underlying mechanisms remain poorly characterized. Using acutely isolated CA1 neurons and slices from the hippocampus, we found that both AEA and 2-AG potentiate NMDAR-mediated currents independently of CB1 receptors (CB1 Rs) and via distinct signaling pathways. Potentiation by AEA requires the activation of TRPV1 channels. In contrast, potentiation by 2-AG requires the sequential activation of PKC and Src. Additionally, in hippocampal slices, we found that both AEA and 2-AG induce NMDAR-mediated metaplasticity and facilitate the induction of subsequent LTD independently of CB1 Rs. Enhanced LTD by AEA, but not 2-AG, was dependent on TRPV1 channels. Our findings reveal previously unrecognized non-CB1 R-dependent signaling cascades through which the two major eCBs regulate NMDA receptor function and consequently synaptic plasticity.
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Ácidos Araquidônicos/metabolismo , Região CA1 Hipocampal/fisiologia , Endocanabinoides/metabolismo , Glicerídeos/metabolismo , Plasticidade Neuronal/fisiologia , Neurônios/fisiologia , Alcamidas Poli-Insaturadas/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Animais , Região CA1 Hipocampal/efeitos dos fármacos , Cálcio/metabolismo , Células Cultivadas , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Feminino , Masculino , Plasticidade Neuronal/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Técnicas de Patch-Clamp , Proteína Quinase C/metabolismo , Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo , Ratos Wistar , Receptor CB1 de Canabinoide/metabolismo , Canais de Cátion TRPV/metabolismo , Técnicas de Cultura de TecidosRESUMO
We found that artesunate (ART) inhibited the growth of MCF-7 and MDA-MB-231 breast cancer cells. ART arrested the cell cycle in the G2/M phase, which was accompanied by an upregulation of p21. ART upregulated the expression of Beclin1, an initiator of autophagy (type II programmed cell death). In addition, ART stimulated the aggregation of LC3, which is considered to be a marker of autophagosome formation. We further verified the transformation of LC3 from type I into type II. 3-MA, a classical autophagy inhibitor, attenuated ART-induced autophagosome formation, cell growth repression, G2/M arrest, and p21 upregulation. Autophagy induction and p21 upregulation were also repressed by knockdown of Beclin1. Furthermore, ART sensitized breast cancer cells to the chemotherapeutic agent epirubicin through an autophagy-dependent cascade. Our study showed that ART induced autophagy in breast cancer cells and indicated that the anticancer effects of ART were exerted through an autophagy pathway. Moreover, ART sensitized breast cancer cells to epirubicin chemotherapy. Our results provide a basis for further development of ART as a novel therapeutic agent for the treatment of breast cancer.
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Antineoplásicos/farmacologia , Artemisininas/farmacologia , Autofagia/efeitos dos fármacos , Neoplasias da Mama/patologia , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Artesunato , Proteína Beclina-1 , Linhagem Celular Tumoral , Sinergismo Farmacológico , Epirubicina/farmacologia , Feminino , Humanos , Proteínas de Membrana/metabolismoRESUMO
Striatal cholinergic interneurons exhibit tonic firing and more positive membrane potentials, however, the mechanism is unclear. In the present study, we found that intracellular perfusion of TRPC3 antibody induced outward current in striatal cholinergic interneurons identified by electrophysiological characteristics. The TRPC3 channel blocker flufenamic acid induced hyperpolarization, and reduced firing rate and outward current which was similar to the effect of TRPC3 channel antibody. Furthermore, by using single-cell RT-PCR we confirmed the co-existence of TRPC3 channel and D5 receptor mRNA in striatal cholinergic interneurons identified by electrophysiological characteristics and expression of choline acetyltransferase (Chat) mRNA. These results implied that the TRPC3 channel is involved in modulating the depolarization of cholinergic interneurons.
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Neurônios Colinérgicos/metabolismo , Corpo Estriado/metabolismo , Interneurônios/metabolismo , Canais de Cátion TRPC/metabolismo , Animais , Técnicas de Patch-Clamp , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
Nociceptive sensory neurons convey pain-related signals to the CNS using action potentials. Loss-of-function mutations in the voltage-gated sodium channel NaV1.7 cause insensitivity to pain (presumably by reducing nociceptor excitability) but clinical trials seeking to treat pain by inhibiting NaV1.7 pharmacologically have struggled. This may reflect the variable contribution of NaV1.7 to nociceptor excitability. Contrary to claims that NaV1.7 is necessary for nociceptors to initiate action potentials, we show that nociceptors can achieve similar excitability using different combinations of NaV1.3, NaV1.7, and NaV1.8. Selectively blocking one of those NaV subtypes reduces nociceptor excitability only if the other subtypes are weakly expressed. For example, excitability relies on NaV1.8 in acutely dissociated nociceptors but responsibility shifts to NaV1.7 and NaV1.3 by the fourth day in culture. A similar shift in NaV dependence occurs in vivo after inflammation, impacting ability of the NaV1.7-selective inhibitor PF-05089771 to reduce pain in behavioral tests. Flexible use of different NaV subtypes exemplifies degeneracy - achieving similar function using different components - and compromises reliable modulation of nociceptor excitability by subtype-selective inhibitors. Identifying the dominant NaV subtype to predict drug efficacy is not trivial. Degeneracy at the cellular level must be considered when choosing drug targets at the molecular level.
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Analgésicos , Benzenossulfonamidas , Nociceptores , Éteres Fenílicos , Animais , Analgésicos/farmacologia , Nociceptores/metabolismo , Nociceptores/efeitos dos fármacos , Canal de Sódio Disparado por Voltagem NAV1.7/metabolismo , Canal de Sódio Disparado por Voltagem NAV1.7/genética , Camundongos , Potenciais de Ação/efeitos dos fármacos , Dor/tratamento farmacológico , Humanos , Canais de Sódio/metabolismo , Canais de Sódio/genética , Canal de Sódio Disparado por Voltagem NAV1.8/metabolismo , Canal de Sódio Disparado por Voltagem NAV1.8/genéticaRESUMO
The intricate and complex interaction between different populations of neurons in the brain has imposed limits on our ability to gain detailed understanding of synaptic transmission and its integration when employing classical electrophysiological approaches. Indeed, electrical field stimulation delivered via traditional microelectrodes does not permit the targeted, precise and selective control of neuronal activity amongst a varied population of neurons and their inputs (eg, cholinergic, dopaminergic or glutamatergic neurons). Recently established optogenetic techniques overcome these limitations allowing precise control of the target neuron populations, which is essential for the elucidation of the neural substrates underlying complex animal behaviors. Indeed, by introducing light-activated channels (ie, microbial opsin genes) into specific neuronal populations, optogenetics enables non-invasive optical control of specific neurons with milliseconds precision. These approaches can readily be applied to freely behaving live animals. Recently there is increased interests in utilizing optogenetics tools to understand synaptic plasticity and learning/memory. Here, we summarize recent progress in applying optogenetics in in the study of synaptic plasticity.
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Plasticidade Neuronal/fisiologia , Optogenética/métodos , Sinapses/fisiologia , Animais , Comportamento Animal/fisiologia , Encéfalo/fisiologia , Humanos , Aprendizagem/fisiologia , Memória/fisiologiaRESUMO
Stroke is a very strong risk factor for dementia. Furthermore, ischemic stroke and Alzheimer's disease (AD) share a number of overlapping mechanisms of neuron loss and dysfunction, including those induced by the inappropriate activation of N-methyl-D-aspartate receptors (NMDARs). These receptors form a major subtype of excitatory glutamate receptor. They are nonselective cation channels with appreciable Ca(2+) permeability, and their overactivation leads to neurotoxicity in the cortex and hippocampus. NMDARs have therefore been therapeutic targets in both conditions, but they have failed in the treatment of stroke, and there is limited rationale for using them in treating AD. In this chapter, we discuss current understanding of subtypes of NMDARs and their potential roles in -ischemic stroke and AD. We also discuss the properties of several other nonselective cation channels, transient receptor potential melastatin 2 and 7 channels, and their implications in linking these conditions.
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Envelhecimento/metabolismo , Doença de Alzheimer/metabolismo , Isquemia Encefálica/metabolismo , Hipocampo/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Canais de Cátion TRPM/metabolismo , Envelhecimento/patologia , Doença de Alzheimer/patologia , Animais , Isquemia Encefálica/patologia , Cálcio/metabolismo , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Hipocampo/patologia , Humanos , Proteínas Serina-Treonina Quinases , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/patologiaRESUMO
Neurons located in the trigeminal subnucleus caudalis (Vc) play crucial roles in pain and sensorimotor functions in the orofacial region. Because of many anatomical and functional similarities with the spinal dorsal horn (SDH), Vc has been termed the medullary dorsal horn--analogous to the SDH. Here, we report that when compared with embryonic SDH neurons in culture, neurons isolated from the Vc region showed significantly slower growth, lower glutamate receptor activity, and more cells undergoing cell death. SDH neuron development was inhibited in co-cultures of SDH and Vc tissues while Vc neuron development was promoted by co-culture with SDH tissues. Furthermore, we identified that small (non-protein) ninhydrin-reacting molecules purified from either embryonic or post-natal Vc-conditioned medium inhibited neuronal growth whereas ninhydrin-reacting molecules from SDH-conditioned medium promoted neuronal growth. These findings suggest the involvement of locally released factors in the region-specific regulation of neuronal development in Vc and SDH, central nervous system regions playing critical roles in pain, and point to novel avenues for investigating central nervous system regionalization and for designing therapeutic approaches to manage neurodegenerative diseases and pain.
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Meios de Cultivo Condicionados/química , Bulbo/citologia , Neurônios/fisiologia , Ninidrina/metabolismo , Medula Espinal/citologia , Animais , Animais Recém-Nascidos , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Processos de Crescimento Celular/efeitos dos fármacos , Processos de Crescimento Celular/fisiologia , Células Cultivadas , Córtex Cerebral/citologia , Cromatografia em Gel , Técnicas de Cocultura , Meios de Cultivo Condicionados/farmacologia , Embrião de Mamíferos , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Ácido Glutâmico/farmacologia , Marcação In Situ das Extremidades Cortadas/métodos , Inibição Neural/efeitos dos fármacos , Inibição Neural/fisiologia , Neurofibromina 1/farmacologia , Neurofibromina 2/farmacologia , Neurônios/efeitos dos fármacos , Técnicas de Cultura de Órgãos , Técnicas de Patch-Clamp , Ratos , Sais de Tetrazólio , Tiazóis , Fatores de TempoRESUMO
Periodontal ligament (PDL) cells are fibroblasts that play key roles in tissue integrity, periodontal inflammation and tissue regeneration in the periodontium. The periodontal tissue destruction in periodontitis is mediated by host tissue-produced inflammatory cytokines, including interleukin-1ß (IL-1ß). Here, we report the expression of G protein-coupled receptor 30 (GPR30, also known as G protein-coupled estrogen receptor 1 GPER) in human PDL cells and its regulation by IL-1ß. IL-1ß-induced GPR30 expression in human PDL cells leads to the activation of multiple signaling pathways, including MAPK, NF-κB and PI3K. In contrast, genistein, an estrogen receptor ligand, postpones the activation of MAPKs induced by IL-1ß. Moreover, the inhibition of GPR30 by G15, a GPR30-specific antagonist, eliminates this delay. Thus, genistein plays a role in the regulation of MAPK activation via GPR30, and GPR30 represents a novel target regulated by steroid hormones in PDL cells.
Assuntos
Genisteína/farmacologia , Interleucina-1beta/fisiologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Ligamento Periodontal/efeitos dos fármacos , Receptores de Estrogênio/fisiologia , Receptores Acoplados a Proteínas G/fisiologia , Adolescente , Sequência de Bases , Células Cultivadas , Primers do DNA , Ativação Enzimática , Feminino , Humanos , Masculino , Ligamento Periodontal/citologia , Ligamento Periodontal/enzimologia , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Estrogênio/antagonistas & inibidores , Receptores Acoplados a Proteínas G/antagonistas & inibidoresRESUMO
MYB proteins play a crucial role in plant growth and development and stress responses. In this study, 160 members of the MYB gene family from the pepper genome database were used to analyze gene structures, chromosome localization, collinearity, genetic affinity and expression in response to heavy metals. The results identified R2R3-MYB members and further phylogenetically classified them into 35 subgroups based on highly conserved gene structures and motifs. Collinearity analysis showed that segmental duplication events played a crucial role in the functional expansion of the CaMYB gene family by intraspecific collinearity, and at least 12 pairs of CaMYB genes existed between species prior to the differentiation between monocots and dicots. Moreover, the upstream CaMYB genes were mainly localized to the phytohormone elements ABRE and transcription factor elements MYB and MYC. Further analysis revealed that MYB transcription factors were closely associated with a variety of abiotic stress-related proteins (e.g., MAC-complex and SKIP). Under the stress of five metal ions, Cd2+, Cu2+, Pb2+, Zn2+, and Fe3+, the expression levels of some CaMYB family genes were upregulated. Of these genes, pairing homologous 1 (PH-1), PH-13, and PH-15 in the roots of Capsicum annuum were upregulated to the greatest extent, indicating that these three MYB family members are particularly sensitive to these five metals. This study provides a theoretical reference for the analysis of the molecular regulatory mechanism of MYB family genes in mediating the response to heavy metals in plants. This study reveals the mode of interaction between MYB and a variety of abiotic stress proteins and clarifies the biological functions of CaMYB family members in the regulation of heavy metal stress.
Assuntos
Capsicum , Metais Pesados , Capsicum/genética , Capsicum/metabolismo , Regulação da Expressão Gênica de Plantas , Metais Pesados/toxicidade , Família Multigênica , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMO
Background: Keloids are benign skin tumors that appears on skin lesions in humans. Keloids are characterized by invasive tumor growth and are highly prone to recurrence after treatment. The incidence of keloids is ethnically specific; however, the molecular mechanism underlying the incidence of keloids in the Chinese population remains unclear. To date, no reports appear to have been published on the molecular characteristics underlying keloids in the Chinese population from the perspective of whole-genome sequencing. Methods: In this study, we collected keloid samples from 9 keloid patients underwent surgery in the Department of Dermatology, The First Affiliated Hospital of Soochow University, paired them to normal skin tissues, and performed whole-exome sequencing. The average depth of the samples was 1,200×, and the average exome coverage was 98.90%. Results: The bioinformatics analysis identified 3,125 single nucleotide variants (SNVs) and 299 insertions/deletions (InDels). The major mutation characteristics of the SNVs were C > A and C > T. The non-synonymous SNV types included stopgain, and stoploss. The non-synonym InDels included frameshift deletion, frameshift insertion, and stopgain. We also found a total of 67,873 copy number variations (CNVs) in the samples. The genes with the highest mutation frequency included mucin 4 (MUC4) (55.6%), tubulin tyrosine ligase like 12 (TTLL12) (33.3%), calcium voltage-gated channel subunit alpha1 (CACNA1C) (33.3%), and mucin 12 (MUC12) (33.3%). The average tumor mutation burden (TMB) was 289 mutations/million base pair (MB). The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that the mutated genes were mainly concentrated in micro ribonucleic acids in cancer and the calcium signaling pathway. The Gene Ontology (GO) analysis showed that mutant genes were mainly concentrated in binding cells, cell parts, and cellular processes. Conclusions: Whole-exome sequencing was performed in the Chinese keloid patients and some potential candidate genes related to keloid occurrence and development were identified, which may provide new molecular targets for the clinical diagnosis and treatment of keloid patients.
RESUMO
As per the theory of traditional Chinese medicine (TCM), the liver and kidney dysfunction are important pathogenies for premature ovarian failure (POF). POF is a common gynecological disease that reduced the pregnancy rate. Electro-acupuncture (EA) is a useful non-pharmaceutical therapy that supposedly regulates the function of the liver and kidney in the treatment of POF with TCM. However, the underlying mechanism of EA in the treatment of POF has not been adequately studied through metabonomics with reference to the theory of TCM. Accordingly, we investigated the effect of EA on the liver and kidney metabolites in POF mice through metabolomics. POF mice were established via intraperitoneal injection of cisplatin. Both Sanyinjiao (SP6) and Guanyuan (CV4) were stimulated by EA for 3 weeks. The biological samples (including the serum and the ovary, liver, and kidney tissues) were evaluated by histopathology, molecular biology, and hydrogen-1 nuclear magnetic resonance (1HNMR)-based metabolomics to assess the efficacy of EA. 1HNMR data were analyzed by the orthogonal partial least squares discriminant analysis (OPLS-DA). The results revealed that EA was beneficial to ovarian function and the menstrual cycle of POF. Both the energy metabolism and neurotransmitter metabolism in the liver and kidney were regulated by EA. Notably, EA played an important role in regulating energy-related metabolism in the kidney, and the better effect of neurotransmitter-related metabolism in the liver was regulated by EA. These findings indicated that the ovarian functions could be improved and the metabolic disorder of the liver and kidney caused by POF could be regulated by EA. Our study results thus suggested that the EA therapy, based on the results for the liver and kidney, were related to POF in TCM, as preliminarily confirmed through metabolomics.