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1.
Nat Neurosci ; 27(4): 643-655, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38424324

RESUMO

Dipeptide repeat proteins are a major pathogenic feature of C9orf72 amyotrophic lateral sclerosis (C9ALS)/frontotemporal dementia (FTD) pathology, but their physiological impact has yet to be fully determined. Here we generated C9orf72 dipeptide repeat knock-in mouse models characterized by expression of 400 codon-optimized polyGR or polyPR repeats, and heterozygous C9orf72 reduction. (GR)400 and (PR)400 knock-in mice recapitulate key features of C9ALS/FTD, including cortical neuronal hyperexcitability, age-dependent spinal motor neuron loss and progressive motor dysfunction. Quantitative proteomics revealed an increase in extracellular matrix (ECM) proteins in (GR)400 and (PR)400 spinal cord, with the collagen COL6A1 the most increased protein. TGF-ß1 was one of the top predicted regulators of this ECM signature and polyGR expression in human induced pluripotent stem cell neurons was sufficient to induce TGF-ß1 followed by COL6A1. Knockdown of TGF-ß1 or COL6A1 orthologues in polyGR model Drosophila exacerbated neurodegeneration, while expression of TGF-ß1 or COL6A1 in induced pluripotent stem cell-derived motor neurons of patients with C9ALS/FTD protected against glutamate-induced cell death. Altogether, our findings reveal a neuroprotective and conserved ECM signature in C9ALS/FTD.


Assuntos
Esclerose Amiotrófica Lateral , Demência Frontotemporal , Células-Tronco Pluripotentes Induzidas , Animais , Humanos , Camundongos , Demência Frontotemporal/patologia , Esclerose Amiotrófica Lateral/metabolismo , Fator de Crescimento Transformador beta1 , Proteína C9orf72/genética , Proteína C9orf72/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Neurônios Motores/metabolismo , Drosophila , Matriz Extracelular/metabolismo , Dipeptídeos/metabolismo , Expansão das Repetições de DNA/genética
2.
Int J Mol Sci ; 25(4)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38397109

RESUMO

Insecticide resistance has long been a problem in crop pest control. Bactericera gobica is a major pest on the well-known medicinal plants Lycium barbarum L. Investigating insecticide resistance mechanisms of B. gobica will help to identify pesticide reduction strategies to control the pest. Gene expression normalization by RT-qPCR requires the selection and validation of appropriate reference genes (RGs). Here, 15 candidate RGs were selected from transcriptome data of B. gobica. Their expression stability was evaluated with five algorithms (Delta Ct, GeNorm, Normfinder, BestKeeper and RefFinder) for sample types differing in response to five insecticide stresses and in four other experimental conditions. Our results indicated that the RGs RPL10 + RPS15 for Imidacloprid and Abamectin; RPL10 + AK for Thiamethoxam; RPL32 + RPL10 for λ-cyhalothrin; RPL10 + RPL8 for Matrine; and EF2 + RPL32 under different insecticide stresses were the most suitable RGs for RT-qPCR normalization. EF1α + RPL8, EF1α + ß-actin, ß-actin + EF2 and ß-actin + RPS15 were the optimal combination of RGs under odor stimulation, temperature, developmental stages and both sexes, respectively. Overall, EF2 and RPL8 were the two most stable RGs in all conditions, while α-TUB and RPL32 were the least stable RGs. The corresponding suitable RGs and one unstable RG were used to normalize a target cytochrome P450 CYP6a1 gene between adult and nymph stages and under imidacloprid stress. The results of CYP6a1 expression were consistent with transcriptome data. This study is the first research on the most stable RG selection in B. gobica nymphs exposed to different insecticides, which will contribute to further research on insecticide resistance mechanisms in B. gobica.


Assuntos
Perfilação da Expressão Gênica , Inseticidas , Neonicotinoides , Nitrocompostos , Masculino , Feminino , Humanos , Perfilação da Expressão Gênica/métodos , Inseticidas/farmacologia , Actinas , Reação em Cadeia da Polimerase em Tempo Real/métodos , Transcriptoma , Padrões de Referência
3.
Cancer Lett ; 582: 216517, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38101609

RESUMO

Src homology 2 domain-containing phosphatase (SHP2) is a non-receptor protein phosphatase that transduces signals from upstream receptor tyrosine kinases (RTKs)/non-RTKs to Ras/MAPK pathway. Accumulating studies indicated that SHP2 is a critical mediator of resistance to current targeted therapies in multiple cancers. Here, we reported a novel SHP2 allosteric inhibitor JC-010a, which was highly selective to SHP2 and bound at the "tunnel" allosteric site of SHP2. The effect of JC-010a on combating RTK/non-RTK or MAPK inhibitors-induced acquired resistance was explored. Our study demonstrated that JC-010a monotherapy significantly inhibited the proliferation of cancer cells with different oncogenic drivers via inhibiting signaling through SHP2. Importantly, JC-010a abolished acquired resistance induced by targeted therapies: in KRAS-mutant cancers, JC-010a abrogated selumetinib-induced adaptive resistance mediated by RTK/SHP2; in BCR-ABL-driven leukemia cells, we demonstrated JC-010a inhibited BCR-ABL T315I mutation-mediated imatinib resistance and proposed a novel mechanism of JC-010a involving the disrupted co-interaction of SHP2, BCR-ABL, and Hsp90; in non-small cell lung cancer (NSCLC) cells, JC-010a inhibited both EGFR T790M/C797S mutation and alternate RTK-driven resistance to gefitinib or osimertinib; importantly, we first proposed a novel potential therapeutic strategy for RET-rearranged cancer, we confirmed that JC-010a monotherapy inhibited cell resistance to BLU-667, and JC-010a/BLU-667 combination prolonged anticancer response both in vivo and in vitro cancer models by inhibiting the alternate MET activation-induced RAS/MAPK reactivation, thereby promoting cancer cell apoptosis. These findings suggested that JC-010a was a novel selective SHP2 allosteric inhibitor, and combing JC-010a with current targeted therapy agents provided a promising therapeutic approach for clinical resistant cancers.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Receptores ErbB/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Inibidores de Proteínas Quinases/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação , Oncogenes , Resistência a Medicamentos , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Linhagem Celular Tumoral
4.
Genes (Basel) ; 14(10)2023 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-37895237

RESUMO

With the development of urban industrialization, the increasing ozone concentration (O3) at ground level stresses on the survival of plants. Plants have to adapt to ozone stress. DNA methylation is crucial for a rapid response to abiotic stress in plants. Little information is known regarding the epigenetic response of DNA methylation of plants to O3 stress. This study is designed to explore the epigenetic mechanism and identify a possible core modification of DNA methylation or genes in the plant, in response to O3 stress. We investigated the agronomic traits and genome-wide DNA methylation variations of the Japonica rice cultivar Nipponbare in response to O3 stress at three high concentrations (80, 160, and 200 nmol·mol-1), simulated using open-top chambers (OTC). The flag leaf length, panicle length, and hundred-grain weight of rice showed beneficial effects at 80 nmol·mol-1 O3 and an inhibitory effect at both 160 and 200 nmol·mol-1 O3. The methylation-sensitive amplified polymorphism results showed that the O3-induced genome-wide methylation alterations account for 14.72-15.18% at three different concentrations. Our results demonstrated that methylation and demethylation alteration sites were activated throughout the O3 stress, mainly at CNG sites. By recovering and sequencing bands with methylation alteration, ten stress-related differentially amplified sequences, widely present on different chromosomes, were obtained. Our findings show that DNA methylation may be an active and rapid epigenetic response to ozone stress. These results can provide us with a theoretical basis and a reference to look for more hereditary information about the molecular mechanism of plant resistance to O3 pollution.


Assuntos
Oryza , Ozônio , Metilação de DNA/genética , Ozônio/toxicidade , Ozônio/metabolismo , Epigênese Genética , Mutação
5.
Exp Appl Acarol ; 91(3): 381-403, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37882995

RESUMO

Phoresy is one of the most distinctive relationships between mites and insects, and the off-host interaction between phoretic mites and their carriers is the most critical factor sustaining the phoretic association. As phoretic associations commonly occur in temporary habitats, little is known about off-host interactions between phoronts and carriers. However, an off-host interaction has been reported, in which the plant-mediated competition between a phoretic gall mite, Aceria pallida, and its psyllid vector, Bactericera gobica, after detachment decreases leaf abscission caused by B. gobica and then directly facilitates their phoretic association. In this obligate phoresy, A. pallida seasonally attaches to B. gobica for overwinter survival and they share the same host plant, Lycium barbarum, during the growing season. It is unknown how the host plant responds to these two herbivores and what plant metabolites are involved in their interspecific interaction. Here, effects of A. pallida and B. gobica on the host plant's transcriptome and metabolome, and on enzymes involved in plant defence, at various infestation stages were studied by inoculating A. pallida and B. gobica either separately or simultaneously on leaves of L. barbarum. Our results showed that (a) A. pallida significantly promoted primary and secondary metabolite accumulation, (b) B. gobica markedly inhibited primary and secondary metabolite accumulation and had little influence on defence enzyme activity, and (c) under simultaneous A. pallida and B. gobica infestation, an intermediate response was predicted. These findings indicate that A. pallida and B. gobica have different effects on host plants, A. pallida inhibits B. gobica mainly by increasing the secondary metabolism of L. barbarum, whereas B. gobica inhibits A. pallida mainly by decreasing the primary metabolism of L. barbarum. In conjunction with our previous research, we speculate that this trade-off in host plant metabolite response between A. pallida and B. gobica after detachment promotes a stable phoretic association.


Assuntos
Hemípteros , Ácaros , Animais , Ácaros/fisiologia
6.
Int J Mol Sci ; 24(11)2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37298504

RESUMO

Transient receptor potential vanilloid 1 (TRPV1), a non-selective cation channel, can be directly activated by oxidants through cysteine modification. However, the patterns of cysteine modification are unclear. Structural analysis showed that the free sulfhydryl groups of residue pairs C387 and C391 were potentially oxidized to form a disulfide bond, which is expected to be closely related to the redox sensing of TRPV1. To investigate if and how the redox states of C387 and C391 activate TRPV1, homology modeling and accelerated molecular dynamic simulations were performed. The simulation revealed the conformational transfer during the opening or closing of the channel. The formation of a disulfide bond between C387 and C391 leads to the motion of pre-S1, which further propagates conformational change to TRP, S6, and the pore helix from near to far. Residues D389, K426, E685-Q691, T642, and T671 contribute to the hydrogen bond transfer and play essential roles in the opening of the channel. The reduced TRPV1 was inactivated mainly by stabilizing the closed conformation. Our study elucidated the redox state of C387-C391 mediated long-range allostery of TRPV1, which provided new insights into the activation mechanism of TRPV1 and is crucial for making significant advances in the treatment of human diseases.


Assuntos
Cisteína , Simulação de Dinâmica Molecular , Humanos , Cisteína/química , Oxirredução , Domínios Proteicos , Dissulfetos , Canais de Cátion TRPV/metabolismo
7.
Spectrochim Acta A Mol Biomol Spectrosc ; 300: 122913, 2023 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-37262970

RESUMO

The prevalence and disease burden of urolithiasis has increased substantially worldwide in the last decade, and intraluminal holmium laser lithotripsy has become the primary treatment method. However, inappropriate laser energy settings increase the risk of perioperative complications, largely due to the lack of intraoperative information on the stone composition, which determines the stone melting point. To address this issue, we developed a fiber-based fluorescence spectrometry method that detects and classifies the autofluorescence spectral fingerprints of urinary stones into three categories: calcium oxalate, uric acid, and struvite. By applying the support vector machine (SVM), the prediction accuracy achieved 90.28 % and 96.70% for classifying calcium stones versus non-calcium stones and uric acid versus struvite, respectively. High accuracy and specificity were achieved for a wide range of working distances and angles between the fiber tip and stone surface in an emulated intraoperative ambient. Our work establishes the methodological basis for engineering a clinical device that achieves real-time, in situ classification of urinary stones for optimizing the laser ablation parameters and reducing perioperative complications in lithotripsy.


Assuntos
Litotripsia a Laser , Cálculos Urinários , Urolitíase , Humanos , Ácido Úrico/análise , Estruvita , Cálculos Urinários/cirurgia , Cálculos Urinários/química
8.
Int J Mol Sci ; 24(12)2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37372986

RESUMO

Galls have become the best model for exploring plant-gall inducer relationships, with most studies focusing on gall-inducing insects but few on gall mites. The gall mite Aceria pallida is a major pest of wolfberry, usually inducing galls on its leaves. For a better understanding of gall mite growth and development, the dynamics of the morphological and molecular characteristics and phytohormones of galls induced by A. pallida were studied by histological observation, transcriptomics and metabolomics. The galls developed from cell elongation of the epidermis and cell hyperplasia of mesophylls. The galls grew quickly, within 9 days, and the mite population increased rapidly within 18 days. The genes involved in chlorophyll biosynthesis, photosynthesis and phytohormone synthesis were significantly downregulated in galled tissues, but the genes associated with mitochondrial energy metabolism, transmembrane transport, carbohydrates and amino acid synthesis were distinctly upregulated. The levels of carbohydrates, amino acids and their derivatives, and indole-3-acetic acid (IAA) and cytokinins (CKs), were markedly enhanced in galled tissues. Interestingly, much higher contents of IAA and CKs were detected in gall mites than in plant tissues. These results suggest that galls act as nutrient sinks and favor increased accumulation of nutrients for mites, and that gall mites may contribute IAA and CKs during gall formation.


Assuntos
Lycium , Ácaros , Animais , Lycium/genética , Ácaros/metabolismo , Transcriptoma , Reguladores de Crescimento de Plantas/metabolismo , Citocininas , Metaboloma , Tumores de Planta/genética , Folhas de Planta/metabolismo
9.
Neurophotonics ; 10(2): 025006, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37152357

RESUMO

Significance: The studying of rapid neuronal signaling across large spatial scales in intact, living brains requires both high temporal resolution and versatility of the measurement device. Aim: We introduce a high-speed two-photon microscope based on a custom-built acousto-optic deflector (AOD). This microscope has a maximum line scan frequency of 400 kHz and a maximum frame rate of 10,000 frames per second (fps) at 250 × 40 pixels . For stepwise magnification from population view to subcellular view with high spatial and temporal resolution, we combined the AOD with resonance-galvo (RS) scanning. Approach: With this combinatorial device that supports both large-view navigation and small-view high-speed imaging, we measured dendritic calcium propagation velocity and the velocity of single red blood cells (RBCs). Results: We measured dendritic calcium propagation velocity ( 80 / 62.5 - 116.7 µ m / ms ) in OGB-1-labeled single cortical neurons in mice in vivo. To benchmark the spatial precision and detection sensitivity of measurement in vivo, we also visualized the trajectories of single RBCs and found that their movement speed follows Poiseuille's law of laminar flow. Conclusions: This proof-of-concept methodological development shows that the combination of AOD and RS scanning two-photon microscopy provides both versatility and precision for quantitative analysis of single neuronal activities and hemodynamics in vivo.

10.
Mar Drugs ; 21(5)2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37233508

RESUMO

Multidrug resistance (MDR) caused by ATP-Binding Cassette Subfamily B Member 1 (ABCB1, P-glycoprotein, P-gp) is a major barrier for the success of chemotherapy in clinics. In this study, we designed and synthesized a total of 19 Lissodendrins B analogues and tested their ABCB1-mediated MDR reversal activity in doxorubicin (DOX)-resistant K562/ADR and MCF-7/ADR cells. Among all derivatives, compounds D1, D2, and D4 with a dimethoxy-substituted tetrahydroisoquinoline fragment possessed potent synergistic effects with DOX and reversed ABCB1-mediated drug resistance. Notably, the most potent compound D1 merits multiple activities, including low cytotoxicity, the strongest synergistic effect, and effectively reversing ABCB1-mediated drug resistance of K562/ADR (RF = 1845.76) and MCF-7/ADR cells (RF = 207.86) to DOX. As a reference substance, compound D1 allows for additional mechanistic studies on ABCB1 inhibition. The synergistic mechanisms were mainly related to the increased intracellular accumulation of DOX via inhibiting the efflux function of ABCB1 rather than from affecting the expression level of ABCB1. These studies suggest that compound D1 and its derivatives might be potential MDR reversal agents acting as ABCB1 inhibitors in clinical therapeutics and provide insight into a design strategy for the development of ABCB1 inhibitors.


Assuntos
Antineoplásicos , Resistencia a Medicamentos Antineoplásicos , Humanos , Resistência a Múltiplos Medicamentos , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Doxorrubicina/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Linhagem Celular Tumoral
11.
J Biol Chem ; 299(4): 103068, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36842500

RESUMO

µ-Conotoxin KIIIA, a selective blocker of sodium channels, has strong inhibitory activity against several Nav isoforms, including Nav1.7, and has potent analgesic effects, but it contains three pairs of disulfide bonds, making structural modification difficult and synthesis complex. To circumvent these difficulties, we designed and synthesized three KIIIA analogues with one disulfide bond deleted. The most active analogue, KIIIA-1, was further analyzed, and its binding pattern to hNav1.7 was determined by molecular dynamics simulations. Guided by the molecular dynamics computational model, we designed and tested 32 second-generation and 6 third-generation analogues of KIIIA-1 on hNav1.7 expressed in HEK293 cells. Several analogues showed significantly improved inhibitory activity on hNav1.7, and the most potent peptide, 37, was approximately 4-fold more potent than the KIIIA Isomer I and 8-fold more potent than the wildtype (WT) KIIIA in inhibiting hNav1.7 current. Intraperitoneally injected 37 exhibited potent in vivo analgesic activity in a formalin-induced inflammatory pain model, with activity reaching ∼350-fold of the positive control drug morphine. Overall, peptide 37 has a simplified disulfide-bond framework and exhibits potent in vivo analgesic effects and has promising potential for development as a pain therapy in the future.


Assuntos
Analgésicos , Conotoxinas , Canal de Sódio Disparado por Voltagem NAV1.7 , Bloqueadores do Canal de Sódio Disparado por Voltagem , Humanos , Analgésicos/farmacologia , Analgésicos/química , Conotoxinas/química , Conotoxinas/farmacologia , Dissulfetos/metabolismo , Células HEK293 , Simulação de Dinâmica Molecular , Dor/induzido quimicamente , Dor/tratamento farmacológico , Peptídeos/farmacologia , Peptídeos/metabolismo , Bloqueadores do Canal de Sódio Disparado por Voltagem/química , Bloqueadores do Canal de Sódio Disparado por Voltagem/farmacologia
12.
Nat Cell Biol ; 25(2): 273-284, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36646788

RESUMO

Impairment of the circadian clock is linked to cancer development. However, whether the circadian clock is modulated by oncogenic receptor tyrosine kinases remains unclear. Here we demonstrated that receptor tyrosine kinase activation promotes CK2-mediated CLOCK S106 phosphorylation and subsequent disassembly of the CLOCK-BMAL1 dimer and suppression of the downstream gene expression in hepatocellular carcinoma (HCC) cells. In addition, CLOCK S106 phosphorylation exposes its nuclear export signal to bind Exportin1 for nuclear exportation. Cytosolic CLOCK acetylates PRPS1/2 K29 and blocks HSC70-mediated and lysosome-dependent PRPS1/2 degradation. Stabilized PRPS1/2 promote de novo nucleotide synthesis and HCC cell proliferation and liver tumour growth. Furthermore, CLOCK S106 phosphorylation and PRPS1/2 K29 acetylation are positively correlated in human HCC specimens and with HCC poor prognosis. These findings delineate a critical mechanism by which oncogenic signalling inhibits canonical CLOCK transcriptional activity and simultaneously confers CLOCK with instrumental moonlighting functions to promote nucleotide synthesis and tumour growth.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Nucleotídeos/metabolismo , Fosforilação
13.
Chem Biol Drug Des ; 102(3): 444-456, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36509697

RESUMO

The natural products plinabulin, docetaxel, and vinblastine are microtubule targeting agents (MTAs). They have been used alone or in combination in cancer treatment. However, the exact nature of their effects on microtubule (MT) polymerization dynamics is poorly understood. To elucidate the longitudinal conformational and energetic changes during MT dynamics, a total of 140 ns molecular dynamic simulations combined with binding free energy calculations were performed on seven tubulin models. The results indicated that the drugs disrupted MT polymerization by altering both MT conformation and binding free energy of the neighboring tubulin subunits. The combination of plinabulin and docetaxel destabilized MT polymerization due to bending MT and weakening the polarity of tubulin polymerization. The new combination of docetaxel and vinblastine synergistically enhanced MT depolymerization and bending, while plinabulin and vinblastine had no synergistic inhibitory effects. The results were verified by the tubulin assembly assay. Our study obtained a comprehensive understanding of the action mechanisms of three natural drugs and their combinations on MT dynamic, provided theoretical guidance for new MTA combinations, and would promote the optimal use of MTA and contribute to developing new MTAs as anticancer agents.


Assuntos
Antineoplásicos , Moduladores de Tubulina , Tubulina (Proteína) , Antineoplásicos/farmacologia , Docetaxel/farmacologia , Docetaxel/metabolismo , Microtúbulos , Tubulina (Proteína)/metabolismo , Vimblastina/farmacologia , Vimblastina/análise , Vimblastina/metabolismo , Moduladores de Tubulina/química , Moduladores de Tubulina/farmacologia
14.
Jpn J Infect Dis ; 2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38171850

RESUMO

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease. Previous studies have mainly focused on the epidemiological and clinical characteristics of patients with SFTS, while pancreatic injury has received little attention. The purpose of this study is to investigate the effect of pancreatic injury on the prognosis of patients with SFTS. A total of 156 SFTS patients were included in the analysis from April 2016 to April 2022. Multivariable logistic regression analysis showed that pancreatic injury (OR=3.754, 95% CI 1.361-79.036, P=0.024) and neurological symptoms (OR=18.648, 95% CI 4.921-70.668, P<0.001) were independent risk factors for patient death. The receiver operating characteristic (ROC) curve indicated that serum pancreatic enzymes (PEs) were predictive of progression to death in SFTS patients. The area under the curve (AUC) for amylase (AMY) was 0.711, with an optimal cut-off value of 95.5 (U/L), sensitivity of 96.4%, and specificity of 35.9%. Lipase (LIP) had an AUC of 0.754, an optimal cut-off value of 354.75 (U/L), a sensitivity of 75%, and a specificity of 67.2%. Thus, pancreatic injury is associated with a poor prognosis of SFTS and can be used as an important reference for SFTS disease determination and prognostic assessment.

15.
Nat Cell Biol ; 24(11): 1655-1665, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36266488

RESUMO

Tumour cells exhibit greater metabolic plasticity than normal cells and possess selective advantages for survival and proliferation with unclearly defined mechanisms. Here we demonstrate that glucose deprivation in normal hepatocytes induces PERK-mediated fructose-1,6-bisphosphatase 1 (FBP1) S170 phosphorylation, which converts the FBP1 tetramer to monomers and exposes its nuclear localization signal for nuclear translocation. Importantly, nuclear FBP1 binds PPARα and functions as a protein phosphatase that dephosphorylates histone H3T11 and suppresses PPARα-mediated ß-oxidation gene expression. In contrast, FBP1 S124 is O-GlcNAcylated by overexpressed O-linked N-acetylglucosamine transferase in hepatocellular carcinoma cells, leading to inhibition of FBP1 S170 phosphorylation and enhancement of ß-oxidation for tumour growth. In addition, FBP1 S170 phosphorylation inversely correlates with ß-oxidation gene expression in hepatocellular carcinoma specimens and patient survival duration. These findings highlight the differential role of FBP1 in gene regulation in normal and tumour cells through direct chromatin modulation and underscore the inactivation of its protein phosphatase function in tumour growth.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/metabolismo , Histonas/genética , Histonas/metabolismo , Frutose-Bifosfatase/genética , PPAR alfa/genética , PPAR alfa/metabolismo , Frutose , Neoplasias Hepáticas/patologia , Transcrição Gênica , Fosfoproteínas Fosfatases/metabolismo
16.
Nanoscale ; 14(39): 14575-14584, 2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36149683

RESUMO

Regulating the electronic structure plays a positive role in improving the ion/electron kinetics of electrode materials for lithium ion batteries (LIBs). Herein, an effective approach is demonstrated to achieve Ni/Mo2C hybrid nanoparticles embedded in porous nitrogen-doped carbon nanofibers (Ni/Mo2C/NC). Density functional theory calculations indicate that Ni can activate the interface of Ni/Mo2C by regulating the electronic structure, and accordingly improve the electron/Li-ion diffusion kinetics. The charge at the interface transfers from Ni atoms to Mo atoms on the surface of Mo2C, illustrating the formation of an interfacial electric field in Ni/Mo2C. The formed interfacial electric field in Ni/Mo2C can improve the intrinsic electronic conductivity, and reduce the Li adsorption energy and the Li+ diffusion barrier. Thus, the obtained Ni/Mo2C/NC shows an excellent high-rate capability of 344.1 mA h g-1 at 10 A g-1, and also displays a superior cyclic performance (remaining at 412.7 mA h g-1 after 1800 cycles at 2 A g-1). This work demonstrates the important role of electronic structure regulation by assembling hybrid materials and provides new guidance for future work on designing novel electrode materials for LIBs.

17.
Dalton Trans ; 51(33): 12620-12629, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-35925026

RESUMO

The electronic structure regulation of electrode materials can improve the ion/electron kinetics, which is beneficial to the cyclic performance and rate capability for lithium ion batteries (LIBs). Herein, we propose a facile strategy to achieve a MoO2/Mo2C/C heterostructure with abundant oxygen vacancies. Density functional theory calculations indicate that the heterostructure of MoO2/Mo2C/C can significantly promote the Li+/charge transfer and reduce the Li adsorption energy, and the abundant oxygen vacancies in MoO2/Mo2C/C can improve the intrinsic electronic conductivity and reduce the Li+ diffusion barrier. Benefiting from the multiscale coordinated regulation, the obtained MoO2/Mo2C/C film exhibits outstanding high rate capability (454.7 mA h g-1 at 5 A g-1) and remarkable cyclic performance (retaining 569 mA h g-1 over 1000 cycles at 2 A g-1). The insightful findings in this study can shed light on the behavior of the electron/ion structure regulation by the heterostructure and oxygen vacancies, which can guide future studies on designing other electrode materials with high-performance lithium-ion storage.

18.
Mar Drugs ; 20(8)2022 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-36005500

RESUMO

Conopeptides are peptides in the venom of marine cone snails that are used for capturing prey or as a defense against predators. A new cysteine-poor conopeptide, Czon1107, has exhibited non-competitive inhibition with an undefined allosteric mechanism in the human (h) α3ß4 nicotinic acetylcholine receptors (nAChRs). In this study, the binding mode of Czon1107 to hα3ß4 nAChR was investigated using molecular dynamics simulations coupled with mutagenesis studies of the peptide and electrophysiology studies on heterologous hα3ß4 nAChRs. Overall, this study clarifies the structure-activity relationship of Czon1107 and hα3ß4 nAChR and provides an important experimental and theoretical basis for the development of new peptide drugs.


Assuntos
Antagonistas Nicotínicos , Receptores Nicotínicos , Dissulfetos/metabolismo , Humanos , Antagonistas Nicotínicos/química , Antagonistas Nicotínicos/farmacologia , Peptídeos/química , Receptores Nicotínicos/metabolismo , Relação Estrutura-Atividade
19.
Front Pharmacol ; 13: 881732, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35754473

RESUMO

A novel 4/8 subtype α-conotoxin, Vt1.27 (NCCMFHTCPIDYSRFNC-NH2), was identified from Conus vitulinus in the South China Sea by RACE methods. The peptide was synthesized and structurally characterized. Similar to other α-conotoxins that target neuronal nicotinic acetylcholine receptor (nAChR) subtypes, Vt1.27 inhibited the rat α3ß2 nAChR subtype (IC50 = 1160 nM) and was inactive at voltage-gated sodium and potassium channels in rat sensory neurons. However, Vt1.27 inhibited high voltage-activated N-type (CaV2.2) calcium channels expressed in HEK293T cells with an IC50 of 398 nM. An alanine scan of the peptide showed that residues Phe5, Pro9, Ile10, and Ser13 contribute significantly to the inhibitory activity of Vt1.27. The molecular dockings indicate that Vt1.27 inhibits the transmembrane region of CaV2.2, which is different from that of ω-conotoxins. Furthermore, Vt1.27 exhibited potent anti-allodynic effect in rat partial sciatic nerve injury (PNL) and chronic constriction injury (CCI) pain models at 10 nmol/kg level with the intramuscular injection. The pain threshold elevation of Vt1.27 groups was higher than that of α-conotoxin Vc1.1 in CCI rat models. These findings expand our knowledge of targets of α-conotoxins and potentially provide a potent, anti-allodynic peptide for the treatment of neuropathic pain.

20.
Environ Sci Pollut Res Int ; 29(39): 59633-59652, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35389168

RESUMO

Joint distribution is an advanced logistics organization model for improving the quality and efficiency of express logistics industry and achieves high-quality development of logistics, but the distribution of common profit has always been a key obstacle to the effective development of joint distribution. Based on the background of green and low carbon, this paper explores a fairer and more reasonable profit distribution scheme. The profit game between the government and the two types of member enterprises is analyzed. By focusing on how the government plays a role in inducing the joint distribution alliance to bring the green and low-carbon requirements into the profit distribution, the strategy evolution process of the three parties, the factors affecting the profit distribution and the stability of alliance are discussed through the establishment of "government-member enterprise A-member enterprise B" tripartite evolutionary game model. Finally, the evolutionary game model is numerically simulated based on system dynamics. It is found that (1) it is necessary for the government to guide and motivate the alliance to create internal incentives and constraints. The effect of government subsidies and rewards to member enterprises is greater than the penalties for member enterprises. (2) The member enterprises are likely to conspire together to defraud government subsidies and rewards, carry out "free riding" and other speculative activities, which makes it necessary for the government and the alliance to establish supervision mechanism, information disclosure mechanism, and property rights protection system. (3) The willingness of member enterprise to positively cooperate will increase with the increase of the additional benefit coefficient, the proportion of profit distribution and the importance of environmental benefit factor; and will decrease with the increase of the cost of promoting green distribution operations.


Assuntos
Carbono , Teoria do Jogo , China , Revelação , Governo , Indústrias
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