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BACKGROUND: Coronary artery disease (CAD) is the leading cause of death worldwide. Recent meta-analyses of genome-wide association studies have identified over 175 loci associated with CAD. The majority of these loci are in noncoding regions and are predicted to regulate gene expression. Given that vascular smooth muscle cells (SMCs) play critical roles in the development and progression of CAD, we aimed to identify the subset of the CAD loci associated with the regulation of transcription in distinct SMC phenotypes. METHODS: We measured gene expression in SMCs isolated from the ascending aortas of 151 heart transplant donors of various genetic ancestries in quiescent or proliferative conditions and calculated the association of their expression and splicing with ~6.3 million imputed single-nucleotide polymorphism markers across the genome. RESULTS: We identified 4910 expression and 4412 splicing quantitative trait loci (sQTLs) representing regions of the genome associated with transcript abundance and splicing. A total of 3660 expression quantitative trait loci (eQTLs) had not been observed in the publicly available Genotype-Tissue Expression dataset. Further, 29 and 880 eQTLs were SMC-specific and sex-biased, respectively. We made these results available for public query on a user-friendly website. To identify the effector transcript(s) regulated by CAD loci, we used 4 distinct colocalization approaches. We identified 84 eQTL and 164 sQTL that colocalized with CAD loci, highlighting the importance of genetic regulation of mRNA splicing as a molecular mechanism for CAD genetic risk. Notably, 20% and 35% of the eQTLs were unique to quiescent or proliferative SMCs, respectively. One CAD locus colocalized with a sex-specific eQTL (TERF2IP), and another locus colocalized with SMC-specific eQTL (ALKBH8). The most significantly associated CAD locus, 9p21, was an sQTL for the long noncoding RNA CDKN2B-AS1, also known as ANRIL, in proliferative SMCs. CONCLUSIONS: Collectively, our results provide evidence for the molecular mechanisms of genetic susceptibility to CAD in distinct SMC phenotypes.
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Doença da Artéria Coronariana , Masculino , Feminino , Humanos , Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/metabolismo , Estudo de Associação Genômica Ampla/métodos , Regulação da Expressão Gênica , Locos de Características Quantitativas , Predisposição Genética para Doença , Expressão Gênica , Polimorfismo de Nucleotídeo Único , Homólogo AlkB 8 da RNAt Metiltransferase/genética , Homólogo AlkB 8 da RNAt Metiltransferase/metabolismoRESUMO
Formation of the vasculature by angiogenesis is critical for proper development, but angiogenesis also contributes to the pathogenesis of various disorders, including cancer and cardiovascular diseases. Vascular endothelial zinc finger 1 (Vezf1), is a Krüppel-like zinc finger protein that plays a vital role in vascular development. However, the mechanism by which Vezf1 regulates this process is not fully understood. Here, we show that Vezf1-/- mouse embryonic stem cells (ESC) have significantly increased expression of a stem cell factor, Cbp/p300-interacting transactivator 2 (Cited2). Compared with WT ESCs, Vezf1-/- ESCs inefficiently differentiated into endothelial cells (ECs), which exhibited defects in the tube-formation assay. These defects were due to reduced activation of EC-specific genes concomitant with lower enrichment of histone 3 acetylation at Lys27 (H3K27) at their promoters. We hypothesized that overexpression of Cited2 in Vezf1-/- cells sequesters P300/CBP away from the promoters of proangiogenic genes and thereby contributes to defective angiogenesis in these cells. This idea was supported by the observation that shRNA-mediated depletion of Cited2 significantly reduces the angiogenic defects in the Vezf1-/- ECs. In contrast to previous studies that have focused on the role of Vezf1 as a transcriptional activator of proangiogenic genes, our findings have revealed a role for Vezf1 in modulating the expression of the antiangiogenic factor Cited2. Vezf1 previously has been characterized as an insulator protein, and our results now provide insights into the mechanism, indicating that Vezf1 can block inappropriate, nonspecific interactions of promoters with cis-located enhancers, preventing aberrant promoter activation.
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Inibidores da Angiogênese/metabolismo , Diferenciação Celular , Células-Tronco Embrionárias/metabolismo , Endotélio Vascular/metabolismo , Regulação da Expressão Gênica , Fatores de Transcrição Kruppel-Like/fisiologia , Proteínas Repressoras/fisiologia , Transativadores/fisiologia , Inibidores da Angiogênese/genética , Animais , Células Cultivadas , Proteínas de Ligação a DNA , Células-Tronco Embrionárias/citologia , Endotélio Vascular/citologia , Camundongos , Camundongos Knockout , Regiões Promotoras Genéticas , Fatores de TranscriçãoRESUMO
Discovery of inhibitors for endothelial-related transcription factors can contribute to the development of anti-angiogenic therapies that treat various diseases, including cancer. The role of transcription factor Vezf1 in vascular development and regulation of angiogenesis has been defined by several earlier studies. Through construction of a computational model for Vezf1, work here has identified a novel small molecule drug capable of inhibiting Vezf1 from binding to its cognate DNA binding site. Using structure-based design and virtual screening of the NCI Diversity Compound Library, 12 shortlisted compounds were tested for their ability to interfere with the binding of Vezf1 to DNA using electrophoretic gel mobility shift assays. We identified one compound, T4, which has an IC50 of 20 µM. Using murine endothelial cells, MSS31, we tested the effect of T4 on endothelial cell viability and angiogenesis by using tube formation assay. Our data show that addition of T4 in cell culture medium does not affect cell viability at concentrations lower or equal to its IC 50 but strongly inhibits the network formation by MSS31 in the tube formation assays. Given its potential efficacy, this inhibitor has significant therapeutic potential in several human diseases.
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Inibidores da Angiogênese/farmacologia , DNA/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Bibliotecas de Moléculas Pequenas/farmacologia , Inibidores da Angiogênese/química , Animais , Proteínas de Ligação a DNA , Células Endoteliais , Regulação da Expressão Gênica , Fatores de Transcrição Kruppel-Like/química , Camundongos , Modelos Moleculares , Simulação de Acoplamento Molecular , Ligação Proteica/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/química , Relação Estrutura-Atividade , Fatores de TranscriçãoRESUMO
The covalent attachment of small ubiquitin-like modifier (SUMO) to target proteins regulates numerous nuclear events in eukaryotes, including transcription, mitosis and meiosis, and DNA repair. Despite extensive interest in nuclear pathways within the field of ciliate molecular biology, there have been no investigations of the SUMO pathway in Tetrahymena. The developmental program of sexual reproduction of this organism includes cell pairing, micronuclear meiosis, and the formation of a new somatic macronucleus. We identified the Tetrahymena thermophila SMT3 (SUMO) and UBA2 (SUMO-activating enzyme) genes and demonstrated that the corresponding green fluorescent protein (GFP) tagged gene products are found predominantly in the somatic macronucleus during vegetative growth. Use of an anti-Smt3p antibody to perform immunoblot assays with whole-cell lysates during conjugation revealed a large increase in SUMOylation that peaked during formation of the new macronucleus. Immunofluorescence using the same antibody showed that the increase was localized primarily within the new macronucleus. To initiate functional analysis of the SUMO pathway, we created germ line knockout cell lines for both the SMT3 and UBA2 genes and found both are essential for cell viability. Conditional Smt3p and Uba2p cell lines were constructed by incorporation of the cadmium-inducible metallothionein promoter. Withdrawal of cadmium resulted in reduced cell growth and increased sensitivity to DNA-damaging agents. Interestingly, Smt3p and Uba2p conditional cell lines were unable to pair during sexual reproduction in the absence of cadmium, consistent with a function early in conjugation. Our studies are consistent with multiple roles for SUMOylation in Tetrahymena, including a dynamic regulation associated with the sexual life cycle.
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Proteínas de Protozoários/metabolismo , Proteína SUMO-1/metabolismo , Sumoilação , Tetrahymena thermophila/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Estágios do Ciclo de Vida , Proteínas de Protozoários/genética , Proteína SUMO-1/genética , Tetrahymena thermophila/crescimento & desenvolvimento , Enzimas Ativadoras de Ubiquitina/genética , Enzimas Ativadoras de Ubiquitina/metabolismoRESUMO
Ubc9p is the sole E2-conjugating enzyme for SUMOylation, and its proper function is required for regulating key nuclear events such as transcription, DNA repair, and mitosis. In Tetrahymena thermophila, the genome is separated into a diploid germ line micronucleus (MIC) that divides by mitosis and a polyploid somatic macronucleus (MAC) that divides amitotically. This unusual nuclear organization provides novel opportunities for the study of SUMOylation and Ubc9p function. We identified the UBC9 gene and demonstrated that its complete deletion from both MIC and MAC genomes is lethal. Rescue of the lethal phenotype with a GFP-UBC9 fusion gene driven by a metallothionein promoter generated a cell line with CdCl2-dependent expression of green fluorescent protein (GFP)-Ubc9p. Depletion of Ubc9p in vegetative cells resulted in the loss of MICs, but MACs continued to divide. In contrast, expression of catalytically inactive Ubc9p resulted in the accumulation of multiple MICs. Critical roles for Ubc9p were also identified during the sexual life cycle of Tetrahymena. Cell lines that were depleted for Ubc9p did not form mating pairs and therefore could not complete any of the subsequent stages of conjugation, including meiosis and macronuclear development. Mating between cells expressing catalytically inactive Ubc9p resulted in arrest during macronuclear development, consistent with our observation that Ubc9p accumulates in the developing macronucleus.
Assuntos
Núcleo Celular/metabolismo , Deleção de Genes , Estágios do Ciclo de Vida , Tetrahymena thermophila/enzimologia , Tetrahymena thermophila/crescimento & desenvolvimento , Enzimas de Conjugação de Ubiquitina/genética , Sequência de Aminoácidos , Linhagem Celular , Dano ao DNA , Técnicas de Inativação de Genes , Genes Dominantes , Genes Essenciais , Recombinação Homóloga/genética , Micronúcleo Germinativo/metabolismo , Dados de Sequência Molecular , Alinhamento de Sequência , Tetrahymena thermophila/genética , Enzimas de Conjugação de Ubiquitina/química , Enzimas de Conjugação de Ubiquitina/metabolismoRESUMO
PURPOSE: Total-body dynamic positron emission tomography (PET) imaging with total-body coverage and ultrahigh sensitivity has played an important role in accurate tracer kinetic analyses in physiology, biochemistry, and pharmacology. However, dynamic PET scans typically entail prolonged durations ([Formula: see text]60 minutes), potentially causing patient discomfort and resulting in artifacts in the final images. Therefore, we propose a dynamic frame prediction method for total-body PET imaging via deep learning technology to reduce the required scanning time. METHODS: On the basis of total-body dynamic PET data acquired from 13 subjects who received [68Ga]Ga-FAPI-04 (68Ga-FAPI) and 24 subjects who received [68Ga]Ga-PSMA-11 (68Ga-PSMA), we propose a bidirectional dynamic frame prediction network that uses the initial and final 10 min of PET imaging data (frames 1-6 and frames 25-30, respectively) as inputs. The peak signal-to-noise ratio (PSNR) and structural similarity index measure (SSIM) were employed as evaluation metrics for an image quality assessment. Moreover, we calculated parametric images (68Ga-FAPI: [Formula: see text], 68Ga-PSMA: [Formula: see text]) based on the supplemented sequence data to observe the quantitative accuracy of our approach. Regions of interest (ROIs) and statistical analyses were utilized to evaluate the performance of the model. RESULTS: Both the visual and quantitative results illustrate the effectiveness of our approach. The generated dynamic PET images yielded PSNRs of 36.056 ± 0.709 dB for the 68Ga-PSMA group and 33.779 ± 0.760 dB for the 68Ga-FAPI group. Additionally, the SSIM reached 0.935 ± 0.006 for the 68Ga-FAPI group and 0.922 ± 0.009 for the 68Ga-PSMA group. By conducting a quantitative analysis on the parametric images, we obtained PSNRs of 36.155 ± 4.813 dB (68Ga-PSMA, [Formula: see text]) and 43.150 ± 4.102 dB (68Ga-FAPI, [Formula: see text]). The obtained SSIM values were 0.932 ± 0.041 (68Ga-PSMA) and 0.980 ± 0.011 (68Ga-FAPI). The ROI analysis conducted on our generated dynamic PET sequences also revealed that our method can accurately predict temporal voxel intensity changes, maintaining overall visual consistency with the ground truth. CONCLUSION: In this work, we propose a bidirectional dynamic frame prediction network for total-body 68Ga-PSMA and 68Ga-FAPI PET imaging with a reduced scan duration. Visual and quantitative analyses demonstrated that our approach performed well when it was used to predict one-hour dynamic PET images. https://github.com/OPMZZZ/BDF-NET .
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Increasing evidence highlights the importance of immune mechanoregulation in establishing and sustaining tumor-specific cytotoxicity required for desirable immunotherapeutic outcomes. However, the molecular connections between mechanobiological inputs and outputs and the designated immune activities remain largely unclear. Here, we show that partial inhibition of non-muscle myosin II (NM II) augmented the traction force exerted by T cells and potentiated T cell cytotoxicity against tumors. By using T cells from mice and patients with cancer, we found that NM II is required for the activity of NKX3-2 in maintaining the expression of ADGRB3, which shapes the filamentous actin (F-actin) organization and ultimately attributes to the reduced traction force of T cells in the tumor microenvironment. In animal models, suppressing the NM II-NKX3-2-ADGRB3 pathway in T cells effectively suppressed tumor growth and improved the efficacy of the checkpoint-specific immunotherapy. Overall, this work provides insights into the biomechanical regulation of T cell cytotoxicity that can be exploited to optimize clinical immunotherapies.
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Neoplasias , Animais , Humanos , Camundongos , Neoplasias/imunologia , Neoplasias/terapia , Neoplasias/metabolismo , Neoplasias/patologia , Microambiente Tumoral/imunologia , Linhagem Celular Tumoral , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , Miosina Tipo II/metabolismo , Citotoxicidade Imunológica , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Actinas/metabolismoRESUMO
With the development of Internet technology, social media has gradually become an important platform where users can express opinions about hot events. Research on the mechanism of public opinion evolution is beneficial to guide the trend of opinions, making users' opinions change in a positive direction or reach a consensus among controversial crowds. To design effective strategies for public opinion management, we propose a dynamic opinion network susceptible-forwarding-immune model considering environmental factors (NET-OE-SFI), which divides the forwarding nodes into two types: support and opposition based on the real data of users. The NET-OE-SFI model introduces environmental factors from infectious diseases into the study of network information transmission, which aims to explore the evolution law of users' opinions affected by the environment. We attempt to combine the complex media environmental factors in social networks with users' opinion information to study the influence of environmental factors on the evolution of public opinion. Data fitting of real information transmission data fully demonstrates the validity of this model. We have also made a variety of sensitivity analysis experiments to study the influence of model parameters, contributing to the design of reasonable and effective strategies for public opinion guidance.
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The skin secretion of tree frogs contains a vast array of bioactive chemicals for repelling predators, but their structural and functional diversity is not fully understood. Paxilline (PAX), a compound synthesized by Penicillium paxilli, has been known as a specific antagonist of large conductance Ca2+-activated K+ Channels (BKCa). Here, we report the presence of PAX in the secretions of tree frogs (Hyla japonica) and that this compound has a novel function of inhibiting the potassium channel subfamily K member 18 (KCNK18) channels of their predators. The PAX-induced KCNK18 inhibition is sufficient to evoke Ca2+ influx in charybdotoxin-insensitive DRG neurons of rats. By forming π-π stacking interactions, four phenylalanines located in the central pore of KCNK18 stabilize PAX to block the ion permeation. For PAX-mediated toxicity, our results from animal assays suggest that the inhibition of KCNK18 likely acts synergistically with that of BKCa to elicit tingling and buzzing sensations in predators or competitors. These results not only show the molecular mechanism of PAX-KCNK18 interaction, but also provide insights into the defensive effects of the enriched PAX.
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Anuros , Indóis , Animais , Ratos , Indóis/farmacologia , Canais de Potássio/metabolismoRESUMO
The two-dimensional layered material CuInP2S6 (CIPS) has attracted significant research attention due to its nontrivial physical properties, including room-temperature ferroelectricity at the ultrathin limit and substantial ionic conductivity. Despite many efforts to control its ionic conductance and develop electronic devices, such as memristors, improving the stability of these devices remains a challenge. This work presents a highly stable threshold-switching device based on the Cu/CIPS/graphene heterostructure, achieved after a comprehensive investigation of the activation of Cu's ionic conductivity. The device exhibits exceptional threshold-switching performance, including good cycling endurance, a high on/off ratio of up to 104, low operation voltages, and an ultrasmall subthreshold swing of less than 1.8 mV/decade for the resistance-switching process. Through temperature-dependent electrical and Raman spectroscopy measurements, the stable resistive-switching mechanism is interpreted with a drifting and diffusion model of Cu ions under the electric field, rather than the conventional conducting filament mechanism. These results make the layered ferroionic CIPS material a promising candidate for information storage devices, demonstrating a compelling approach to achieving high-performance threshold-switching memristor devices.
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Protein kinase C (PKC) activation was previously associated with oncogenic features. However, small molecule inhibitors targeting PKC have so far proved ineffective in a number of clinical trials for cancer treatment. Recent progresses have revealed that most PKC mutations detected in diverse cancers actually lead to loss-of-function, thus suggesting the tumor-suppressive roles of PKC proteins. Unfortunately, the development of chemicals to enhance PKC activity is lagging behind relative to its small molecular inhibitors. Here, we report that a bisindolylmaleimide derivative (3,4-bis(1-(prop-2-ynyl)-1H-indol-3-yl)-1 H-pyrrole-2,5-dione, BD-15) significantly inhibited cell growth in non-small cell lung cancer (NSCLC). Mechanistically, BD-15 treatment resulted in markedly enhanced phosphorylation of PKC substrates and led to cell cycle arrest in G2/M. Further, BD-15 treatment upregulated p21 protein levels and enhanced p21 phosphorylation. BD-15 also promoted caspase3 cleavage and triggered cellular apoptosis. In xenograft mouse models, BD-15 exerted anti-tumor effects to suppress in vivo tumor formation. Collectively, our findings revealed the tumor-suppressive roles of BD-15 through enhancing PKC signaling and thus leading to upregulation of p21 expression and phosphorylation.
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Genome-wide association studies identified single nucleotide polymorphisms on chromosome 7 upstream of KLF14 to be associated with metabolic syndrome traits and increased risk for type 2 diabetes (T2D). The associations were more significant in women than in men. The risk allele carriers expressed lower levels of the transcription factor KLF14 in adipose tissues than nonrisk allele carriers. To investigate how adipocyte KLF14 regulates metabolic traits in a sex-dependent manner, we characterized high-fat diet-fed male and female mice with adipocyte-specific Klf14 deletion or overexpression. Klf14 deletion resulted in increased fat mass in female mice and decreased fat mass in male mice. Female Klf14-deficient mice had overall smaller adipocytes in subcutaneous fat depots but larger adipocytes in parametrial depots, indicating a shift in lipid storage from subcutaneous to visceral fat depots. They had reduced metabolic rates and increased respiratory exchange ratios consistent with increased use of carbohydrates as an energy source. Fasting- and isoproterenol-induced adipocyte lipolysis was defective in female Klf14-deficient mice, and concomitantly, adipocyte triglycerides lipase mRNA levels were downregulated. Female Klf14-deficient mice cleared blood triglyceride and nonesterified fatty acid less efficiently than wild-type. Finally, adipocyte-specific overexpression of Klf14 resulted in lower total body fat in female but not male mice. Taken together, consistent with human studies, adipocyte KLF14 deficiency in female but not in male mice causes increased adiposity and redistribution of lipid storage from subcutaneous to visceral adipose tissues. Increasing KLF14 abundance in adipocytes of females with obesity and T2D may provide a novel treatment option to alleviate metabolic abnormalities.
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Adiposidade , Diabetes Mellitus Tipo 2 , Fatores de Transcrição Kruppel-Like , Metabolismo dos Lipídeos , Fatores Sexuais , Adipócitos/metabolismo , Adiposidade/genética , Animais , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Estudo de Associação Genômica Ampla , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Metabolismo dos Lipídeos/genética , Masculino , Camundongos , Obesidade/genética , Obesidade/metabolismoRESUMO
PURPOSE: The epidermal growth factor receptor (EGFR) represents a top therapeutic target in the treatment of non-small cell lung cancer. EGFR expression is intricately modulated by receptor endocytosis, during which EGFR ubiquitylation and deubiquitylation play fundamental roles to govern receptor fate. This study aims to uncover novel aspects of the endocytic regulation of EGFR trafficking by deubiquitylases. METHODS: The expression and ubiquitylation of EGFR in non-small cell lung cancer cells treated with deubiquitylase inhibitors were assessed by immunoblotting, immunoprecipitation and mass spectrometry analyses. The intracellular EGFR distribution was investigated using immunofluorescence and confocal microscopy assays, and colocalizations with endocytic compartments were examined using GFP-tagged Rab proteins as markers. The influence of the proteasomal deubiquitylase inhibitor b-AP15 on EGF- and HSP90 inhibitor-induced EGFR downregulation was evaluated by immunoblotting. The anticancer effects of b-AP15 were assessed by cell proliferation, colony formation and flow cytometry assays, as well as xenograft animal models. RESULTS: We found that b-AP15 caused a dramatically enhanced ubiquitylation of EGFR in lung cancer cells. Treatment with b-AP15 decreased cell surface EGFR levels and accumulated EGFR on recycling endosomes marked with Rab4A and Rab11A. b-AP15 effectively repressed EGF- and HSP90 inhibitor-induced EGFR degradation. Lung cancer cells exposed to b-AP15 showed markedly reduced cell propagation and significantly increased cell apoptosis. Furthermore, b-AP15 effectively inhibited tumor xenograft growth in nude mice. CONCLUSION: Proteasomal USP14 and UCHL5 act collectively to promote cell surface recovery of EGFR. Inhibition of proteasomal deubiquitylase activity induces increased EGFR ubiquitylation and retention on recycling endosomes. The USP14 and UCHL5 dual inhibitor b-AP15 elicits potent tumor-suppressive effects to deter cell proliferation and induce apoptotic cell death in lung cancer.
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Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Animais , Humanos , Camundongos , Antineoplásicos/farmacologia , Apoptose , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Fator de Crescimento Epidérmico/farmacologia , Receptores ErbB/metabolismo , Neoplasias Pulmonares/patologia , Camundongos Nus , Inibidores de Proteassoma/farmacologia , Ubiquitina Tiolesterase/metabolismoRESUMO
Contagious itch behavior informs conspecifics of adverse environment and is crucial for the survival of social animals. Gastrin-releasing peptide (GRP) and its receptor (GRPR) in the suprachiasmatic nucleus (SCN) of the hypothalamus mediates contagious itch behavior in mice. Here, we show that intrinsically photosensitive retina ganglion cells (ipRGCs) convey visual itch information, independently of melanopsin, from the retina to GRP neurons via PACAP-PAC1R signaling. Moreover, GRPR neurons relay itch information to the paraventricular nucleus of the thalamus (PVT). Surprisingly, neither the visual cortex nor superior colliculus is involved in contagious itch. In vivo calcium imaging and extracellular recordings reveal contagious itch-specific neural dynamics of GRPR neurons. Thus, we propose that the retina-ipRGC-SCN-PVT pathway constitutes a previously unknown visual pathway that probably evolved for motion vision that encodes salient environmental cues and enables animals to imitate behaviors of conspecifics as an anticipatory mechanism to cope with adverse conditions.
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Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Vias Visuais , Animais , Cálcio/metabolismo , Peptídeo Liberador de Gastrina/metabolismo , Camundongos , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Prurido/metabolismo , Retina/metabolismo , Células Ganglionares da Retina/metabolismo , Núcleo Supraquiasmático/metabolismo , Vias Visuais/metabolismoRESUMO
Solid electrolytes with high Li-ion conductivity and electrochemical stability are very important for developing high-performance all-solid-state batteries. In this work, Li2(BH4)(NH2) is nanoconfined in the mesoporous silica molecule sieve (SBA-15) using a melting-infiltration approach. This electrolyte exhibits excellent Li-ion conduction properties, achieving a Li-ion conductivity of 5.0 × 10-3 S cm-1 at 55 °C, an electrochemical stability window of 0 to 3.2 V and a Li-ion transference number of 0.97. In addition, this electrolyte can enable the stable cycling of Li|Li2(BH4)(NH2)@SBA-15|TiS2 cells, which exhibit a reversible specific capacity of 150 mAh g-1 with a Coulombic efficiency of 96% after 55 cycles.
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Histamine-dependent and -independent itch is conveyed by parallel peripheral neural pathways that express gastrin-releasing peptide (GRP) and neuromedin B (NMB), respectively, to the spinal cord of mice. B-type natriuretic peptide (BNP) has been proposed to transmit both types of itch via its receptor NPRA encoded by Npr1. However, BNP also binds to its cognate receptor, NPRC encoded by Npr3 with equal potency. Moreover, natriuretic peptides (NP) signal through the Gi-couped inhibitory cGMP pathway that is supposed to inhibit neuronal activity, raising the question of how BNP may transmit itch information. Here, we report that Npr3 expression in laminae I-II of the dorsal horn partially overlaps with NMB receptor (NMBR) that transmits histaminergic itch via Gq-couped PLCß-Ca2+ signaling pathway. Functional studies indicate that NPRC is required for itch evoked by histamine but not chloroquine (CQ), a nonhistaminergic pruritogen. Importantly, BNP significantly facilitates scratching behaviors mediated by NMB, but not GRP. Consistently, BNP evoked Ca2+ responses in NMBR/NPRC HEK 293 cells and NMBR/NPRC dorsal horn neurons. These results reveal a previously unknown mechanism by which BNP facilitates NMB-encoded itch through a novel NPRC-NMBR cross-signaling in mice. Our studies uncover distinct modes of action for neuropeptides in transmission and modulation of itch in mice.
An itch is a common sensation that makes us want to scratch. Most short-term itches are caused by histamine, a chemical that is released by immune cells following an infection or in response to an allergic reaction. Chronic itching, on the other hand, is not usually triggered by histamine, and is typically the result of neurological or skin disorders, such as atopic dermatitis. The sensation of itching is generated by signals that travel from the skin to nerve cells in the spinal cord. Studies in mice have shown that the neuropeptides responsible for delivering these signals differ depending on whether or not the itch involves histamine: GRPs (short for gastrin-releasing proteins) convey histamine-independent itches, while NMBs (short for neuromedin B) convey histamine-dependent itches. It has been proposed that another neuropeptide called BNP (short for B-type natriuretic peptide) is able to transmit both types of itch signals to the spinal cord. But it remains unclear how this signaling molecule is able to do this. To investigate, Meng, Liu, Liu, Liu et al. carried out a combination of behavioral, molecular and pharmacological experiments in mice and nerve cells cultured in a laboratory. The experiments showed that BNP alone cannot transmit the sensation of itching, but it can boost itching signals that are triggered by histamine. It is widely believed that BNP activates a receptor protein called NPRA. However, Meng et al. found that the BNP actually binds to another protein which alters the function of the receptor activated by NMBs. These findings suggest that BNP modulates rather than initiates histamine-dependent itching by enhancing the interaction between NMBs and their receptor. Understanding how itch signals travel from the skin to neurons in the spinal cord is crucial for designing new treatments for chronic itching. The work by Meng et al. suggests that treatments targeting NPRA, which was thought to be a key itch receptor, may not be effective against chronic itching, and that other drug targets need to be explored.
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Peptídeo Natriurético Encefálico/genética , Neurocinina B/análogos & derivados , Prurido/genética , Receptores do Fator Natriurético Atrial/genética , Transdução de Sinais , Animais , Gânglios Espinais/metabolismo , Células HEK293 , Histamina/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Peptídeo Natriurético Encefálico/metabolismo , Neurocinina B/genética , Neurocinina B/metabolismo , Prurido/fisiopatologia , Receptores do Fator Natriurético Atrial/metabolismo , Medula Espinal/metabolismoRESUMO
Metabolic syndrome (MetSyn) is a combination of metabolic abnormalities that lead to the development of cardiovascular disease (CVD) and Type 2 Diabetes (T2D). Although various criteria for defining MetSyn exist, common abnormalities include abdominal obesity, elevated serum triglyceride, insulin resistance, and blood glucose, decreased high-density lipoprotein cholesterol (HDL-C), and hypertension. MetSyn prevalence has been increasing with the rise of obesity worldwide, with significantly higher prevalence in women compared with men and in Hispanics compared with Whites. Affected individuals are at a higher risk of developing T2D (5-fold) and CVD (2-fold). Heritability estimates for individual components of MetSyn vary between 40 and 70%, suggesting a strong contribution of an individual's genetic makeup to disease pathology. The advent of next-generation sequencing technologies has enabled large-scale genome-wide association studies (GWAS) into the genetics underlying MetSyn pathogenesis. Several such studies have implicated the transcription factor KLF14, a member of the Krüpple-like factor family (KLF), in the development of metabolic diseases, including obesity, insulin resistance, and T2D. How KLF14 regulates these metabolic traits and increases the risk of developing T2D, atherosclerosis, and liver dysfunction is still unknown. There have been some debate and controversial results with regards to its expression profile and functionality in various tissues, and a systematic review of current knowledge on KLF14 is lacking. Here, we summarize the research progress made in understanding the function of KLF14 and describe common attributes of its biochemical, physiological, and pathophysiological roles. We also discuss the current challenges in understanding the role of KLF14 in metabolism and provide suggestions for future directions.
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Gastrin-releasing peptide (GRP) functions as a neurotransmitter for non-histaminergic itch, but its site of action (sensory neurons vs spinal cord) remains controversial. To determine the role of GRP in sensory neurons, we generated a floxed Grp mouse line. We found that conditional knockout of Grp in sensory neurons results in attenuated non-histaminergic itch, without impairing histamine-induced itch. Using a Grp-Cre knock-in mouse line, we show that the upper epidermis of the skin is exclusively innervated by GRP fibers, whose activation via optogeneics and chemogenetics in the skin evokes itch- but not pain-related scratching or wiping behaviors. In contrast, intersectional genetic ablation of spinal Grp neurons does not affect itch nor pain transmission, demonstrating that spinal Grp neurons are dispensable for itch transmission. These data indicate that GRP is a neuropeptide in sensory neurons for non-histaminergic itch, and GRP sensory neurons are dedicated to itch transmission.
Assuntos
Peptídeo Liberador de Gastrina/genética , Peptídeo Liberador de Gastrina/metabolismo , Dor/metabolismo , Prurido/metabolismo , Células Receptoras Sensoriais/metabolismo , Medula Espinal/metabolismo , Animais , Modelos Animais de Doenças , Técnicas de Inativação de Genes , Histamina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurotransmissores , Dor/patologia , Prurido/patologia , Células Receptoras Sensoriais/patologia , Pele/metabolismo , Pele/patologia , TranscriptomaRESUMO
Introduction: Self-reported smoking has been associated with higher seropositivity for the IgA response to Epstein-Barr virus (EBV) viral capsid antigen (VCA-IgA) and transcription activator protein (Zta) in healthy men in southern China where nasopharyngeal carcinoma (NPC) is endemic. Results on the association of biochemically verified smoking status with EBV reactivation are scarce. We aimed to investigate the relations of serum cotinine level with serological markers of EBV in healthy women, in addition to men. Methods: We collected information on demographic, lifestyle, environmental factors, and EBV serological markers in a cross-sectional study on 2,275 healthy subjects who were recruited from physical examination centers in Guangdong Province, China. In the present analysis, 901 subjects' serum cotinine levels have been measured by enzyme-linked immunosorbent assay (ELISA). Odds ratios (seropositivity of four EBV serological markers vs. seronegativity) for categorical serum cotinine levels were calculated by unconditional logistic regression with a group-specific confidence interval (CI). Results: In women, compared with lower serum cotinine level (0-0.71 ng/ml), higher cotinine level (>0.71-1.20 ng/ml; >1.20-228.40 ng/ml) was associated but non-significantly with higher seropositivity for EBV VCA-IgA (age- and education-adjusted OR = 1.18, 95% CIs = 0.84-1.64, 1.06, 0.75-1.50). These associations remained but still non-significant after adjusting for 5-year age group, education, family history of cancer, consumption of tea, Chinese herbal tea, salted fish at childhood, and exposure to occupational dust, chemical, fume, and radiation (multivariable adjusted OR = 1.21, 95% CIs = 0.85-1.71, 1.09, 0.76-1.55). In men, compared with lower serum cotinine level (0-2.15 ng/ml), higher cotinine level (>2.15-103.6 ng/ml; >103.6-419.4 ng/ml) was significantly associated with higher seropositivity for EBV VCA-IgA and Zta-IgA (age- and education-adjusted OR = 2.16, 95% CIs = 1.37-3.41, 1.79, 1.11-2.90; 1.98, 1.17-3.34, 1.95, 1.14-3.34). The association remained significant after adjusting for potential confounders for Zta-IgA (OR = 2.32, 95% CI = 1.37-3.93 for >2.15-103.6, and 2.50, 1.43-4.38 for >103.6-419.4 ng/ml), but not for VCA-IgA (2.06, 1.29-3.27, and 1.61, 0.96-2.71). Conclusions: Higher serum cotinine level is associated with higher seropositivity for EBV serological markers in healthy men in southern China. Such positive association was also observed in women but became non-significant. If confirmed to be causal, this finding has important implications for tobacco control and prevention of EBV-related disease, particularly for NPC.
RESUMO
The aim of this study was to detect IL36RN variant types and frequency in Han patients with generalized pustular psoriasis (GPP) in Sichuan region of China, reveal the difference of variant frequency between GPP alone and GPPâ+âPV (psoriasis vulgaris), and preliminarily clarify the pathogenesis of GPP in this region.Genomic DNA was extracted and subjected to polymerase chain reaction (PCR) for the amplification of the entire encoding and splice sites of the IL36RN gene followed by bidirectional sequencing. Differences in frequencies of IL36RN variants between groups were analyzed by SPSS Statistics 17.0 software. Meanwhile, the IL36RN variant frequency between GPP alone and GPPâ+âPV was compared.The total IL36RN variant frequency was 60.47% in Han GPP patients from Sichuan region of China. Three variant types (c.115â+â6Tâ>âC, c.140Aâ>âG, c.227Câ>âT) were identified, among which c.115â+â6Tâ>âC exhibited the highest frequency (55.81%). All the 3 variants' frequency of GPP alone group had statistical significance when compared with PV patients and normal controls (Pâ<â.05). The IL36RN variant frequency of GPP alone group was statistically higher than that of GPPâ+âPV group (79.17% vs 36.84%, Pâ<â.05).IL36RN may be the major disease-causing gene in GPP patients in Han population in Sichuan region of China. c.115â+â6Tâ>âC is a possible hot-spot mutation within the IL36RN gene. In contrast to GPPâ+âPV, IL36RN mutations possibly play a more important role in the development of GPP alone.