Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Resultados 1 - 20 de 65
Filtrar
1.
Brief Bioinform ; 22(5)2021 09 02.
Artículo en Inglés | MEDLINE | ID: mdl-33594424

RESUMEN

m6A RNA methylation is an emerging epigenetic modification, and its potential role in immunity and stemness remains unknown. Based on 17 widely recognized m6A regulators, the m6A modification patterns and corresponding characteristics of immune infiltration and stemness of 1152 low-grade glioma samples were comprehensively analyzed. Machine-learning strategies for constructing m6AScores were trained to quantify the m6A modification patterns of individual samples. Here, we reveal a significant correlation between the multi-omics data of regulators and clinicopathological parameters. We identified two distinct m6A modification patterns (an immune-activated differentiation pattern and an immune-desert dedifferentiation pattern) and four regulatory patterns of m6A methylation on immunity and stemness. We show that the m6AScores can predict the molecular subtype of low-grade glioma, the abundance of immune infiltration, the enrichment of signaling pathways, gene variation and prognosis. The concentration of high immunogenicity and clinical benefits in the low-m6AScore group confirmed the sensitive response to radio-chemotherapy and immunotherapy in patients with high-m6AScore. The results of the pan-cancer analyses illustrate the significant correlation between m6AScore and clinical outcome, the burden of neoepitope, immune infiltration and stemness. The assessment of individual tumor m6A modification patterns will guide us in improving treatment strategies and developing objective diagnostic tools.


Asunto(s)
Adenosina/análogos & derivados , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/inmunología , Metilación de ADN/genética , Regulación Neoplásica de la Expresión Génica/inmunología , Glioma/genética , Glioma/inmunología , Inmunidad Innata , Metiltransferasas/genética , Proteínas de Unión al ARN/genética , Adenosina/genética , Biomarcadores de Tumor/genética , Neoplasias Encefálicas/patología , Variaciones en el Número de Copia de ADN , Epigénesis Genética , Glioma/patología , Humanos , Linfocitos Infiltrantes de Tumor/inmunología , Aprendizaje Automático , Tasa de Mutación , Fenotipo , Pronóstico , Microambiente Tumoral/genética , Microambiente Tumoral/inmunología
2.
J Cell Mol Med ; 25(20): 9543-9556, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34547170

RESUMEN

Osteosarcoma (OS) is a type of malignant primary bone cancer, which is highly aggressive and occurs more commonly in children and adolescents. Thus, novel potential drugs and therapeutic methods are urgently needed. In the present study, we aimed to elucidate the effects and mechanism of melatonin on OS cells to provide a potential treatment strategy for OS. The cell survival rate, cell viability, proliferation, migration, invasion and metastasis were examined by trypan blue assay, MTT, colony formation, wound healing, transwell invasion and attachment/detachment assay, respectively. The expression of relevant lncRNAs in OS cells was determined by real-time qPCR analysis. The functional roles of lncRNA JPX in OS cells were further examined by gain and loss of function assays. The protein expression was measured by western blot assay. Melatonin inhibited the cell viability, proliferation, migration, invasion and metastasis of OS cells (Saos-2, MG63 and U2OS) in a dose-dependent manner. Melatonin treatment significantly downregulated the expression of lncRNA JPX in Saos-2, MG63 and U2OS cells. Overexpression of lncRNA JPX into OS cell lines elevated the cell viability and proliferation, which was accompanied by the increased metastasis. We also found that melatonin inhibited the OS progression by suppressing the expression of lncRNA JPX via regulating the Wnt/ß-catenin pathway. Our results suggested that melatonin inhibited the biological functions of OS cells by repressing the expression of lncRNA JPX through regulating the Wnt/ß-catenin signalling pathway, which indicated that melatonin might be applied as a potentially useful and effective natural agent in the treatment of OS.


Asunto(s)
Antineoplásicos/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Melatonina/farmacología , ARN Largo no Codificante/genética , Vía de Señalización Wnt/efectos de los fármacos , Neoplasias Óseas/genética , Neoplasias Óseas/metabolismo , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/efectos de los fármacos , Humanos , Osteosarcoma/genética , Osteosarcoma/metabolismo
3.
Proc Natl Acad Sci U S A ; 111(24): 8961-6, 2014 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-24889629

RESUMEN

Stimulating presynaptic terminals can increase the proton concentration in synapses. Potential receptors for protons are acid-sensing ion channels (ASICs), Na(+)- and Ca(2+)-permeable channels that are activated by extracellular acidosis. Those observations suggest that protons might be a neurotransmitter. We found that presynaptic stimulation transiently reduced extracellular pH in the amygdala. The protons activated ASICs in lateral amygdala pyramidal neurons, generating excitatory postsynaptic currents. Moreover, both protons and ASICs were required for synaptic plasticity in lateral amygdala neurons. The results identify protons as a neurotransmitter, and they establish ASICs as the postsynaptic receptor. They also indicate that protons and ASICs are a neurotransmitter/receptor pair critical for amygdala-dependent learning and memory.


Asunto(s)
Canales Iónicos Sensibles al Ácido/genética , Amígdala del Cerebelo/fisiología , Plasticidad Neuronal , Neurotransmisores/metabolismo , Protones , Sinapsis/fisiología , Bloqueadores del Canal Iónico Sensible al Ácido/química , Acidosis , Amígdala del Cerebelo/metabolismo , Animales , Encéfalo/metabolismo , Electrodos , Potenciales Postsinápticos Excitadores , Concentración de Iones de Hidrógeno , Canales Iónicos/química , Aprendizaje , Potenciación a Largo Plazo , Memoria , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Neuronas/metabolismo , Técnicas de Cultivo de Órganos , Técnicas de Placa-Clamp , Péptidos/química , Venenos de Araña/química
4.
Proc Natl Acad Sci U S A ; 110(8): 3083-8, 2013 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-23382208

RESUMEN

Peripheral nervous system abnormalities, including neuropathy, have been reported in people with cystic fibrosis. These abnormalities have largely been attributed to secondary manifestations of the disease. We tested the hypothesis that disruption of the cystic fibrosis transmembrane conductance regulator (CFTR) gene directly influences nervous system function by studying newborn CFTR(-/-) pigs. We discovered CFTR expression and activity in Schwann cells, and loss of CFTR caused ultrastructural myelin sheath abnormalities similar to those in known neuropathies. Consistent with neuropathic changes, we found increased transcripts for myelin protein zero, a gene that, when mutated, can cause axonal and/or demyelinating neuropathy. In addition, axon density was reduced and conduction velocities of the trigeminal and sciatic nerves were decreased. Moreover, in vivo auditory brainstem evoked potentials revealed delayed conduction of the vestibulocochlear nerve. Our data suggest that loss of CFTR directly alters Schwann cell function and that some nervous system defects in people with cystic fibrosis are likely primary.


Asunto(s)
Animales Recién Nacidos , Regulador de Conductancia de Transmembrana de Fibrosis Quística/fisiología , Sistema Nervioso Periférico/fisiopatología , Animales , Axones , Secuencia de Bases , Sistema Nervioso Central/metabolismo , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Regulador de Conductancia de Transmembrana de Fibrosis Quística/metabolismo , Cartilla de ADN , Masculino , Vaina de Mielina/genética , Vaina de Mielina/patología , Sistema Nervioso Periférico/metabolismo , Reacción en Cadena de la Polimerasa , Porcinos
5.
Am J Physiol Heart Circ Physiol ; 308(3): H157-82, 2015 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-25416190

RESUMEN

The transient receptor potential (TRP) superfamily consists of a large number of nonselective cation channels with variable degree of Ca(2+)-permeability. The 28 mammalian TRP channel proteins can be grouped into six subfamilies: canonical, vanilloid, melastatin, ankyrin, polycystic, and mucolipin TRPs. The majority of these TRP channels are expressed in different cell types including both excitable and nonexcitable cells of the cardiovascular system. Unlike voltage-gated ion channels, TRP channels do not have a typical voltage sensor, but instead can sense a variety of other stimuli including pressure, shear stress, mechanical stretch, oxidative stress, lipid environment alterations, hypertrophic signals, and inflammation products. By integrating multiple stimuli and transducing their activity to downstream cellular signal pathways via Ca(2+) entry and/or membrane depolarization, TRP channels play an essential role in regulating fundamental cell functions such as contraction, relaxation, proliferation, differentiation, and cell death. With the use of targeted deletion and transgenic mouse models, recent studies have revealed that TRP channels are involved in numerous cellular functions and play an important role in the pathophysiology of many diseases in the cardiovascular system. Moreover, several TRP channels are involved in inherited diseases of the cardiovascular system. This review presents an overview of current knowledge concerning the physiological functions of TRP channels in the cardiovascular system and their contributions to cardiovascular diseases. Ultimately, TRP channels may become potential therapeutic targets for cardiovascular diseases.


Asunto(s)
Sistema Cardiovascular/metabolismo , Cardiopatías/metabolismo , Canales de Potencial de Receptor Transitorio/metabolismo , Animales , Sistema Cardiovascular/crecimiento & desarrollo , Cardiopatías/genética , Humanos , Transducción de Señal , Canales de Potencial de Receptor Transitorio/química , Canales de Potencial de Receptor Transitorio/genética
6.
bioRxiv ; 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38853906

RESUMEN

Emotion regulation, essential for adaptive behavior, depends on the brain's capacity to process a range of emotions. Current research has largely focused on individual emotional circuits without fully exploring how their interaction influences physiological responses or understanding the neural mechanisms that differentiate emotional valence. Using in vivo calcium imaging, electrophysiology, and optogenetics, we examined neural circuit dynamics in the medial prefrontal cortex (mPFC), targeting two key areas: the basal lateral amygdala (BLA) and nucleus accumbens (NAc). Our results demonstrate distinct activation patterns in the mPFC→BLA and mPFC→NAc pathways in response to social stimuli, indicating a mechanism for discriminating emotions: increased mPFC→BLA activity signals anxiety, while heightened mPFC→NAc responses are linked to exploration. Additionally, chronic emotional states amplify activity in these pathways-positivity enhances mPFC→NAc, while negativity boosts mPFC→BLA. This study sheds light on the nuanced neural circuitry involved in emotion regulation, revealing the pivotal roles of mPFC projections in emotional processing. Identifying these specific circuits engaged by varied emotional states advances our understanding of emotional regulation's biological underpinnings and highlights potential targets for addressing emotional dysregulation in psychiatric conditions. Significance statement: While existing circuitry studies have underscored the significance of emotional circuits, the majority of research has concentrated on individual circuits. The assessment of whether and how the balance among multiple circuits influences overall physiological outcomes is often overlooked. This study delves into the neural underpinnings of emotion regulation, focusing on how positive and negative valences are discriminated and managed. By examining the specific pathways from the medial prefrontal cortex (mPFC) to key emotional centers-the basal lateral amygdala (BLA) for negative valence and the nucleus accumbens (NAc) for positive one-we uncovered a novel dual-balanced neural circuit mechanism that enables this essential aspect of human cognition.

7.
eNeuro ; 11(9)2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39266326

RESUMEN

Rett syndrome (RTT), a severe neurodevelopmental disorder caused by mutations in the MeCP2 gene, is characterized by cognitive and social deficits. Previous studies have noted hypoactivity in the medial prefrontal cortex (mPFC) pyramidal neurons of MeCP2-deficient mice (RTT mice) in response to both social and nonsocial stimuli. To further understand the neural mechanisms behind the social deficits of RTT mice, we monitored excitatory pyramidal neurons in the prelimbic region of the mPFC during social interactions in mice. These neurons' activity was closely linked to social preference, especially in wild-type mice. However, RTT mice showed reduced social interest and corresponding hypoactivity in these neurons, indicating that impaired mPFC activity contributes to their social deficits. We identified six mPFC neural ensembles selectively tuned to various stimuli, with RTT mice recruiting fewer neurons to ensembles responsive to social interactions and consistently showing lower stimulus-ON ensemble transient rates. Despite these lower rates, RTT mice exhibited an increase in the percentage of social-ON neurons in later sessions, suggesting a compensatory mechanism for the decreased firing rate. This highlights the limited plasticity in the mPFC caused by MeCP2 deficiency and offers insights into the neural dynamics of social encoding. The presence of multifunctional neurons and those specifically responsive to social or object stimuli in the mPFC emphasizes its crucial role in complex behaviors and cognitive functions, with selective neuron engagement suggesting efficiency in neural activation that optimizes responses to environmental stimuli.


Asunto(s)
Proteína 2 de Unión a Metil-CpG , Corteza Prefrontal , Células Piramidales , Síndrome de Rett , Animales , Corteza Prefrontal/fisiología , Corteza Prefrontal/metabolismo , Proteína 2 de Unión a Metil-CpG/deficiencia , Proteína 2 de Unión a Metil-CpG/genética , Síndrome de Rett/fisiopatología , Síndrome de Rett/genética , Masculino , Células Piramidales/fisiología , Conducta Social , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neuronas/fisiología , Neuronas/metabolismo , Modelos Animales de Enfermedad , Potenciales de Acción/fisiología , Interacción Social , Femenino
8.
Sci Adv ; 10(43): eadn7573, 2024 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-39453995

RESUMEN

Social dominance is essential for maintaining a stable society and has both positive and negative impacts on social animals, including humans. However, the regulatory mechanisms governing social dominance, as well as the crucial regulators and biomarkers involved, remain poorly understood. We discover that mice lacking acid-sensing ion channel 2 (ASIC2) exhibit persistently higher social dominance than their wild-type cagemates. Conversely, overexpression of ASIC2 in the medial prefrontal cortex reverses the dominance hierarchy observed in ASIC2 knockout (Asic2-/-) mice. Asic2-/- neurons exhibit increased synaptic transmission and plasticity, potentially mediated by protein kinase A signaling pathway. Furthermore, ASIC2 plays distinct functional roles in excitatory and inhibitory neurons, thereby modulating the balance of neuronal activities underlying social dominance behaviors-a phenomenon suggestive of a cell subtype-specific mechanism. This research lays the groundwork for understanding the mechanisms of social dominance, offering potential insights for managing social disorders, such as depression and anxiety.


Asunto(s)
Canales Iónicos Sensibles al Ácido , Ratones Noqueados , Corteza Prefrontal , Predominio Social , Animales , Corteza Prefrontal/metabolismo , Canales Iónicos Sensibles al Ácido/metabolismo , Canales Iónicos Sensibles al Ácido/genética , Ratones , Neuronas/metabolismo , Transmisión Sináptica , Masculino , Plasticidad Neuronal , Conducta Animal , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Transducción de Señal
9.
bioRxiv ; 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39345364

RESUMEN

Transient receptor potential canonical (TRPC) channels are widely expressed in the brain; however, their precise roles in neurodegeneration, such as Alzheimer's disease (AD) remain elusive. Bioinformatic analysis of the published single-cell RNA-seq data collected from AD patient cohorts indicates that the Trpc3 gene is uniquely upregulated in excitatory neurons. TRPC3 expression is also upregulated in post-mortem AD brains, and in both acute and chronic mouse models of AD. Functional screening of TRPC3 antagonists resulted in a lead inhibitor JW-65, which completely rescued Aß-induced neurotoxicity, impaired synaptic plasticity (e.g., LTP), and learning memory in acute and chronic experimental AD models. In cultured rat hippocampal neurons, we found that treatment with soluble ß-amyloid oligomers (AßOs) induces rapid and sustained upregulation of the TRPC3 expression selectively in excitatory neurons. This aberrantly upregulated TRPC3 contributes to AßOs-induced Ca 2+ overload through the calcium entry and store-release mechanisms. The neuroprotective action of JW-65 is primarily mediated via restoring AßOs-impaired Ca 2+ /calmodulin-mediated signaling pathways, including calmodulin kinases CaMKII/IV and calcineurin (CaN). The synaptic protective mechanism via TRPC3 inhibition was further supported by hippocampal RNA-seq data from the symptomatic 5xFAD mice after chronic treatment with JW-65. Overall, these findings not only validate TRPC3 as a novel therapeutic target for treating synaptic dysfunction of AD but most importantly, disclose a distinct role of upregulated TRPC3 in AD pathogenesis in mediating Ca 2+ dyshomeostasis.

10.
bioRxiv ; 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37693395

RESUMEN

Following a stroke, the emergence of amygdala-related disorders poses a significant challenge, with severe implications for post-stroke mental health, including conditions such as anxiety and depression. These disorders not only hinder post-stroke recovery but also elevate mortality rates. Despite their profound impact, the precise origins of aberrant amygdala function after stroke remain elusive. As a target of reduced brain pH in ischemia, acid-sensing ion channels (ASICs) have been implicated in synaptic transmission after ischemia, hinting at their potential role in reshaping neural circuits following a stroke. This study delves into the intriguing relationship between post-stroke alterations and ASICs, specifically focusing on postsynaptic ASIC1a enhancement in the amygdala following prefrontal cortex (PFC) ischemia induced by endothelin-1 (ET-1) injection. Our findings intriguingly illustrate that mPFC ischemia not only accentuates the PFC to amygdala circuit but also implicates ASIC1a in fostering augmented synaptic plasticity after ischemia. In contrast, the absence of ASIC1a impairs the heightened induction of long-term potentiation (LTP) in the amygdala induced by ischemia. This pivotal research introduces a novel concept with the potential to inaugurate an entirely new avenue of inquiry, thereby significantly enhancing our comprehension of the intricate mechanisms underlying post-stroke neural circuit reconfiguration. Importantly, these revelations hold the promise of paving the way for groundbreaking therapeutic interventions.

11.
Brain Sci ; 13(12)2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38137132

RESUMEN

Following a stroke, the emergence of amygdala-related disorders poses a significant challenge, with severe implications for post-stroke mental health, including conditions such as anxiety and depression. These disorders not only hinder post-stroke recovery but also elevate mortality rates. Despite their profound impact, the precise origins of aberrant amygdala function after a stroke remain elusive. As a target of reduced brain pH in ischemia, acid-sensing ion channels (ASICs) have been implicated in synaptic transmission after ischemia, hinting at their potential role in reshaping neural circuits following a stroke. This study delves into the intriguing relationship between post-stroke alterations and ASICs, specifically focusing on postsynaptic ASIC1a enhancement in the amygdala following prefrontal cortex (PFC) ischemia induced by endothelin-1 (ET-1) injection. Our findings intriguingly illustrate that mPFC ischemia not only accentuates the PFC to the amygdala circuit but also implicates ASIC1a in fostering augmented synaptic plasticity after ischemia. In contrast, the absence of ASIC1a impairs the heightened induction of long-term potentiation (LTP) in the amygdala induced by ischemia. This pivotal research introduces a novel concept with the potential to inaugurate an entirely new avenue of inquiry, thereby significantly enhancing our comprehension of the intricate mechanisms underlying post-stroke neural circuit reconfiguration. Importantly, these revelations hold the promise of paving the way for groundbreaking therapeutic interventions.

12.
bioRxiv ; 2023 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-37693494

RESUMEN

Neuronal activity promotes high-grade glioma progression via secreted proteins and neuron-to-glioma synapses, and glioma cells boost neuronal activity to further reinforce the malignant cycle. Whereas strong evidence supports that the activity of neuron-to-glioma synapses accelerates tumor progression, the molecular mechanisms that modulate the formation and function of neuron-to-glioma synapses remain largely unknown. Our recent findings suggest that a proton (H + ) signaling pathway actively mediates neuron-to-glioma synaptic communications by activating neuronal acid-sensing ion channel 1a (Asic1a), a predominant H + receptor in the central nervous system (CNS). Supporting this idea, our preliminary data revealed that local acid puff on neurons in high-grade glioma-bearing brain slices induces postsynaptic currents of glioma cells. Stimulating Asic1a knockout (Asic1a -/- ) neurons results in lower AMPA receptor-dependent excitatory postsynaptic currents (EPSCs) in glioma cells than stimulating wild-type (WT) neurons. Moreover, glioma-bearing Asic1a -/- mice exhibited reduced tumor size and survived longer than the glioma-bearing WT mice. Finally, pharmacologically targeting brain Asic1a inhibited high-grade glioma progression. In conclusion, our findings suggest that the neuronal H + -Asic1a axis plays a key role in regulating the neuron-glioma synapse. The outcomes of this study will greatly expand our understanding of how this deadly tumor integrates into the neuronal microenvironment.

13.
bioRxiv ; 2023 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-37873397

RESUMEN

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been associated with a wide range of "long COVID" neurological symptoms. However, the mechanisms governing SARS-CoV-2 neurotropism and its effects on long-term behavioral changes remain poorly understood. Using a highly virulent mouse-adapted SARS-CoV-2 strain, denoted as SARS2-N501Y MA30 , we demonstrated that intranasal inoculation of SARS2-N501Y MA30 results in viral dissemination to multiple brain regions, including the amygdala and hippocampus. Behavioral assays show a significant increase in anxiety- and depression-like behaviors 14 days following viral infection. Moreover, we observed microglia activation following SARS2-N501Y MA30 infection, along with an augmentation in microglia-dependent neuronal activity in the amygdala. Pharmacological inhibition of microglial activity subsequent to viral spike inoculation mitigates microglia-dependent neuronal hyperactivity. Furthermore, transcriptomic analysis of infected brains revealed the upregulation of inflammatory and cytokine-related pathways, implicating microglia-driven neuroinflammation in the pathogenesis of neuronal hyperactivity and behavioral abnormality. Overall, these data provide critical insights into the neurological consequences of SARS-CoV-2 infection and underscore microglia as a potential therapeutic target for ameliorating virus-induced neurobehavioral abnormalities.

14.
Ann Transl Med ; 11(2): 52, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36819520

RESUMEN

Background: Although Andrographis paniculata (AP) exhibits various biological functions such as anticancer, anti-inflammatory, antimalarial, antimicrobial, antioxidant, cardioprotective and immunomodulatory, its role in estrogen deficiency-related osteoporosis remains unclear. Methods: Ovariectomy (OVX)-induced estrogen deficiency-related osteoporotic mouse models and sham mouse models were established using 8-week-old female C57BL/6J mice. Micro-computed tomography (µCT) scanning was performed to assess the skeletal phenotype. The differentiation potential of bone marrow mesenchymal stem cells (BMSCs) from the OVX and sham groups was assessed by osteogenic or adipogenic induction medium in vitro. To verify the effects of AP, alizarin red S (ARS) staining, alkaline phosphatase (ALP) staining and oil red O (ORO) staining, reverse transcription assay and quantitative real-time polymerase chain reaction were applied to detect the lineage differentiation ability of BMSCs. Results: µCT scanning showed that AP treatment attenuated the osteoporotic phenotype in OVX-induced estrogen deficiency-related osteoporotic mice. The results of ARS staining, ALP staining, ORO staining and quantitative real-time polymerase chain reaction indicated that BMSCs from OVX-induced osteoporotic mice displayed a significant reduction in osteogenic differentiation and an increase in adipogenic differentiation, which could be reversed by AP treatment. Conclusions: Our findings suggested that AP regulated the differentiation potential of BMSCs and ameliorated the development of estrogen deficiency-related osteoporosis, which might be an effective therapeutic method for estrogen deficiency-related osteoporosis.

15.
Circ Res ; 106(5): 992-1003, 2010 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-20075334

RESUMEN

RATIONALE: Cardiac fibrosis contributes to pathogenesis of atrial fibrillation (AF), which is the most commonly sustained arrhythmia and a major cause of morbidity and mortality. Although it has been suggested that Ca(2+) signals are involved in fibrosis promotion, the molecular basis of Ca(2+) signaling mechanisms and how Ca(2+) signals contribute to fibrogenesis remain unknown. OBJECTIVE: To determine the molecular mechanisms of Ca(2+)-permeable channel(s) in human atrial fibroblasts, and to investigate how Ca(2+) signals contribute to fibrogenesis in human AF. METHODS AND RESULTS: We demonstrate that the transient receptor potential (TRP) melastatin related 7 (TRPM7) is the molecular basis of the major Ca(2+)-permeable channel in human atrial fibroblasts. Endogenous TRPM7 currents in atrial fibroblasts resemble the biophysical and pharmacological properties of heterologous expressed TRPM7. Knocking down TRPM7 by small hairpin RNA largely eliminates TRPM7 current and Ca(2+) influx in atrial fibroblasts. More importantly, atrial fibroblasts from AF patients show a striking upregulation of both TRPM7 currents and Ca(2+) influx and are more prone to myofibroblast differentiation, presumably attributable to the enhanced expression of TRPM7. TRPM7 small hairpin RNA markedly reduced basal AF fibroblast differentiation. Transforming growth factor (TGF)-beta1, the major stimulator of atrial fibrosis, requires TRPM7-mediated Ca(2+) signal for its effect on fibroblast proliferation and differentiation. Furthermore, TGF-beta1-induced differentiation of cultured human atrial fibroblasts is well correlated with an increase of TRPM7 expression induced by TGF-beta1. CONCLUSIONS: Our results establish that TRPM7 is the major Ca(2+)-permeable channel in human atrial fibroblasts and likely plays an essential role in TGF-beta1-elicited fibrogenesis in human AF.


Asunto(s)
Fibrilación Atrial/metabolismo , Señalización del Calcio , Fibroblastos/metabolismo , Canales Catiónicos TRPM/metabolismo , Anciano , Anciano de 80 o más Años , Animales , Fibrilación Atrial/patología , Diferenciación Celular , Permeabilidad de la Membrana Celular , Proliferación Celular , Femenino , Fibroblastos/patología , Fibrosis , Atrios Cardíacos/metabolismo , Atrios Cardíacos/patología , Humanos , Masculino , Potenciales de la Membrana , Ratones , Proteínas Serina-Treonina Quinasas , Interferencia de ARN , Canales Catiónicos TRPM/genética , Factor de Crecimiento Transformador beta1/metabolismo , Regulación hacia Arriba
16.
Proc Natl Acad Sci U S A ; 106(17): 7239-44, 2009 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-19372375

RESUMEN

Melastatin-related transient receptor potential channel 2 (TRPM2) is a Ca(2+)-permeable, nonselective cation channel that is involved in oxidative stress-induced cell death and inflammation processes. Although TRPM2 can be activated by ADP-ribose (ADPR) in vitro, it was unknown how TRPM2 is gated in vivo. Moreover, several alternative spliced isoforms of TRPM2 identified recently are insensitive to ADPR, and their gating mechanisms remain unclear. Here, we report that intracellular Ca(2+) ([Ca(2+)](i)) can activate TRPM2 as well as its spliced isoforms. We demonstrate that TRPM2 mutants with disrupted ADPR-binding sites can be activated readily by [Ca(2+)](i), indicating that [Ca(2+)](i) gating of TRPM2 is independent of ADPR. The mechanism by which [Ca(2+)](i) activates TRPM2 is via a calmodulin (CaM)-binding domain in the N terminus of TRPM2. Whereas Ca(2+)-mediated TRPM2 activation is independent of ADPR and ADPR-binding sites, both [Ca(2+)](i) and the CaM-binding motif are required for ADPR-mediated TRPM2 gating. Importantly, we demonstrate that intracellular Ca(2+) release activates both recombinant and endogenous TRPM2 in intact cells. Moreover, receptor activation-induced Ca(2+) release is capable of activating TRPM2. These results indicate that [Ca(2+)](i) is a key activator of TRPM2 and the only known activator of the spliced isoforms of TRPM2. Our findings suggest that [Ca(2+)](i)-mediated activation of TRPM2 and its alternative spliced isoforms may represent a major gating mechanism in vivo, therefore conferring important physiological and pathological functions of TRPM2 and its spliced isoforms in response to elevation of [Ca(2+)](i).


Asunto(s)
Empalme Alternativo/genética , Calcio/metabolismo , Espacio Intracelular/metabolismo , Canales Catiónicos TRPM/metabolismo , Adenosina Difosfato Ribosa/metabolismo , Secuencia de Aminoácidos , Sitios de Unión , Calmodulina/metabolismo , Línea Celular , Fenómenos Electrofisiológicos , Humanos , Datos de Secuencia Molecular , Mutación/genética , Técnicas de Placa-Clamp , Canales Catiónicos TRPM/química , Canales Catiónicos TRPM/genética
17.
Front Immunol ; 13: 871564, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35572524

RESUMEN

Angiogenesis is a complex process in the immunosuppressed low-grade gliomas (LGG) microenvironment and is regulated by multiple factors. N6-methyladenosine (m6A), modified by the m6A modification regulators ("writers" "readers" and "erasers"), can drive LGG formation. In the hypoxic environment of intracranial tumor immune microenvironment (TIME), m6A modifications in glioma stem cells are predominantly distributed around neovascularization and synergize with complex perivascular pathological ecology to mediate the immunosuppressive phenotype of TIME. The exact mechanism of this phenomenon remains unknown. Herein, we elucidated the relevance of the angiogenesis-related genes (ARGs) and m6A regulators (MAGs) and their influencing mechanism from a macro perspective. Based on the expression pattern of MAGs, we divided patients with LGG into two robust categories via consensus clustering, and further annotated the malignant related mechanisms and corresponding targeted agents. The two subgroups (CL1, CL2) demonstrated a significant correlation with prognosis and clinical-pathology features. Moreover, WGCNA has also uncovered the hub genes and related mechanisms of MAGs affecting clinical characters. Clustering analysis revealed a synergistic promoting effect of M6A and angiogenesis on immunosuppression. Based on the expression patterns of MAGs, we established a high-performance gene-signature (MASig). MASig revealed somatic mutational mechanisms by which MAGs affect the sensitivity to treatment in LGG patients. In conclusion, the MAGs were critical participants in the malignant process of LGG, with a vital potential in the prognosis stratification, prediction of outcome, and therapeutic sensitivity of LGG. Findings based on these strategies may facilitate the development of objective diagnosis and treatment systems to quantify patient survival and other outcomes, and in some cases, to identify potential unexplored targeted therapies.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Glioma , Biomarcadores de Tumor/genética , Glioma/tratamiento farmacológico , Glioma/genética , Glioma/patología , Humanos , Terapia de Inmunosupresión , Pronóstico , Microambiente Tumoral/genética
18.
Front Neurol ; 13: 886913, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35669882

RESUMEN

Background: In recent years, glioblastoma multiforme (GBM) has been a concern of many researchers, as it is one of the main drivers of cancer-related deaths worldwide. GBM in general usually does not responding well to immunotherapy due to its unique microenvironment. Methods: To uncover any further informative immune-related prognostic signatures, we explored the immune-related distinction in the genetic or epigenetic features of the three types (expression profile, somatic mutation, and DNA methylation). Twenty eight immune-related hub genes were identified by Weighted Gene Co-Expression Network Analysis (WGCNA). The findings showed that three genes (IL1R1, TNFSF12, and VDR) were identified to construct an immune-related prognostic model (IRPM) by lasso regression. Then, we used three hub genes to construct an IRPM for GBM and clarify the immunity, mutation, and methylation characteristics. Results: Survival analysis of patients undergoing anti-program cell death protein 1 (anti-PD-1) therapy showed that overall survival was superior in the low-risk group than in the high-risk group. The high-risk group had an association with epithelial-mesenchymal transition (EMT), high immune cell infiltration, immune activation, a low mutation number, and high methylation, while the low-risk group was adverse status. Conclusions: In conclusion, IRPM is a promising tool to distinguish the prognosis of patients and molecular and immune characteristics in GBM, and the IRPM risk score can be used to predict patient sensitivity to checkpoint inhibitor blockade therapy. Thus, three immune-related signatures will guide us in improving treatment strategies and developing objective diagnostic tools.

19.
J Photochem Photobiol B ; 234: 112537, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35939916

RESUMEN

BACKGROUND: photodynamics therapy (PDT) induces tumor cell death through oxidative stress and is closely associated with the expression of hypoxia inducible factor-1a (HIF1a), which activates multiple downstream survival signaling pathways. Therefore, the purpose of this study was to investigate the expression levels of HIF1a proteins in PDT-treated GBM cells and to determine whether inhibition of HIF1a reduces survival signals to enhance the efficacy of PDT. RESULTS: PDT combined with Acriflavine (ACF, PA) decreased the expression of HIF1a and regulated the downstream expression of GLUT-1, GLUT-3, HK2 and other gluconeogenic pathway proteins. PA group significantly suppressed tumor growth to improve the efficacy of PDT. METHODS: We first performed the correlation of HIF1a, GLUT-1, GLUT-3, and HK2, and quantified the expression of HIF1a on tumor grades and IDH mutation classification by TCGA and CGGA databases. Then, we used immunohistochemistry method to detect four gene expression levels in human GBM tissues. Besides, we examined the effects of different treatments on the proliferation, migration and invasion ability of GBM cell lines by CCK8, wound healing and transwell assays. ACF, a HIF1a/HIF1ß dimerization inhibitor, was used to evaluate its adjuvant effect on the efficacy of PDT. CONCLUSION: HIF1a is activated in GBM cell lines and contributes to the survival of tumor cells after PDT in vitro and in vivo. PA group inhibited HIF1a expression and improved PDT efficacy in the treatment of recalcitrant GBM.


Asunto(s)
Glioblastoma , Fotoquimioterapia , Acriflavina/farmacología , Acriflavina/uso terapéutico , Línea Celular Tumoral , Proliferación Celular , Glioblastoma/tratamiento farmacológico , Humanos , Factor 1 Inducible por Hipoxia/farmacología , Subunidad alfa del Factor 1 Inducible por Hipoxia , Transducción de Señal
20.
Front Cell Dev Biol ; 10: 887693, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35656554

RESUMEN

The epithelial-mesenchymal transition (EMT) is an important process that drives progression, metastasis, and oncology treatment resistance in cancers. Also, the adjacent non-tumor tissue may affect the biological properties of cancers and have potential prognostic implications. Our study aimed to identify EMT-related genes in LGG samples, explore their impact on the biological properties of lower grade gliomas (LGG) through the multi-omics analysis, and reveal the potential mechanism by which adjacent non-tumor tissue participated in the malignant progression of LGG. Based on the 121 differentially expressed EMT-related genes between normal samples from the GTEx database and LGG samples in the TCGA cohort, we identified two subtypes and constructed EMTsig. Because of the genetic, epigenetic, and transcriptomic heterogeneity, malignant features including clinical traits, molecular traits, metabolism, anti-tumor immunity, and stemness features were different between samples with C1 and C2. In addition, EMTsig could also quantify the EMT levels, variation in prognosis, and oncology treatment sensitivity of LGG patients. Therefore, EMTsig could assist us in developing objective diagnostic tools and in optimizing therapeutic strategies for LGG patients. Notably, with the GSVA, we found that adjacent non-tumor tissue might participate in the progression, metastasis, and formation of the tumor microenvironment in LGG. Therefore, the potential prognostic implications of adjacent non-tumor tissue should be considered when performing clinical interventions for LGG patients. Overall, our study investigated and validated the effects of EMT-related genes on the biological properties from multiple perspectives, and provided new insights into the function of adjacent non-tumor tissue in the malignant progression of LGG.

SELECCIÓN DE REFERENCIAS
Detalles de la búsqueda