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1.
Mol Cell ; 83(12): 1956-1958, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37327770

RESUMO

In this issue of Molecular Cell, Yu et al.1 identify RBM33 as a previously unrecognized m6A (N-6-methyladenosine) RNA binding protein that plays a critical role in ALKBH5-mediated m6A demethylation of a subset of mRNA transcripts by forming a complex with ALKBH5.


Assuntos
Adenosina , Homólogo AlkB 5 da RNA Desmetilase , Metilação , Homólogo AlkB 5 da RNA Desmetilase/genética , Homólogo AlkB 5 da RNA Desmetilase/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Adenosina/genética , Adenosina/metabolismo
2.
PLoS Genet ; 19(3): e1010319, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36976799

RESUMO

One of the most common cell shape changes driving morphogenesis in diverse animals is the constriction of the apical cell surface. Apical constriction depends on contraction of an actomyosin network in the apical cell cortex, but such actomyosin networks have been shown to undergo continual, conveyor belt-like contractions before the shrinking of an apical surface begins. This finding suggests that apical constriction is not necessarily triggered by the contraction of actomyosin networks, but rather can be triggered by unidentified, temporally-regulated mechanical links between actomyosin and junctions. Here, we used C. elegans gastrulation as a model to seek genes that contribute to such dynamic linkage. We found that α-catenin and ß-catenin initially failed to move centripetally with contracting cortical actomyosin networks, suggesting that linkage is regulated between intact cadherin-catenin complexes and actomyosin. We used proteomic and transcriptomic approaches to identify new players, including the candidate linkers AFD-1/afadin and ZYX-1/zyxin, as contributing to C. elegans gastrulation. We found that ZYX-1/zyxin is among a family of LIM domain proteins that have transcripts that become enriched in multiple cells just before they undergo apical constriction. We developed a semi-automated image analysis tool and used it to find that ZYX-1/zyxin contributes to cell-cell junctions' centripetal movement in concert with contracting actomyosin networks. These results identify several new genes that contribute to C. elegans gastrulation, and they identify zyxin as a key protein important for actomyosin networks to effectively pull cell-cell junctions inward during apical constriction. The transcriptional upregulation of ZYX-1/zyxin in specific cells in C. elegans points to one way that developmental patterning spatiotemporally regulates cell biological mechanisms in vivo. Because zyxin and related proteins contribute to membrane-cytoskeleton linkage in other systems, we anticipate that its roles in regulating apical constriction in this manner may be conserved.


Assuntos
Actomiosina , Caenorhabditis elegans , Animais , Actomiosina/genética , Actomiosina/metabolismo , Zixina/genética , Zixina/metabolismo , Caenorhabditis elegans/metabolismo , Constrição , Proteômica , Junções Intercelulares/genética , Junções Intercelulares/metabolismo , Morfogênese/genética
3.
Proc Natl Acad Sci U S A ; 120(31): e2301260120, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37487097

RESUMO

Lithium-sulfur (Li-S) batteries with high energy density and low cost are promising for next-generation energy storage. However, their cycling stability is plagued by the high solubility of lithium polysulfide (LiPS) intermediates, causing fast capacity decay and severe self-discharge. Exploring electrolytes with low LiPS solubility has shown promising results toward addressing these challenges. However, here, we report that electrolytes with moderate LiPS solubility are more effective for simultaneously limiting the shuttling effect and achieving good Li-S reaction kinetics. We explored a range of solubility from 37 to 1,100 mM (based on S atom, [S]) and found that a moderate solubility from 50 to 200 mM [S] performed the best. Using a series of electrolyte solvents with various degrees of fluorination, we formulated the Single-Solvent, Single-Salt, Standard Salt concentration with Moderate LiPSs solubility Electrolytes (termed S6MILE) for Li-S batteries. Among the designed electrolytes, Li-S cells using fluorinated-1,2-diethoxyethane S6MILE (F4DEE-S6MILE) showed the highest capacity of 1,160 mAh g-1 at 0.05 C at room temperature. At 60 °C, fluorinated-1,4-dimethoxybutane S6MILE (F4DMB-S6MILE) gave the highest capacity of 1,526 mAh g-1 at 0.05 C and an average CE of 99.89% for 150 cycles at 0.2 C under lean electrolyte conditions. This is a fivefold increase in cycle life compared with other conventional ether-based electrolytes. Moreover, we observed a long calendar aging life, with a capacity increase/recovery of 4.3% after resting for 30 d using F4DMB-S6MILE. Furthermore, the correlation between LiPS solubility, degree of fluorination of the electrolyte solvent, and battery performance was systematically investigated.

4.
Nucleic Acids Res ; 51(8): 3793-3805, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-37014011

RESUMO

Maternal mitochondria are the sole source of mtDNA for every cell of the offspring. Heteroplasmic mtDNA mutations inherited from the oocyte are a common cause of metabolic diseases and associated with late-onset diseases. However, the origin and dynamics of mtDNA heteroplasmy remain unclear. We used our individual Mitochondrial Genome sequencing (iMiGseq) technology to study mtDNA heterogeneity, quantitate single nucleotide variants (SNVs) and large structural variants (SVs), track heteroplasmy dynamics, and analyze genetic linkage between variants at the individual mtDNA molecule level in single oocytes and human blastoids. Our study presented the first single-mtDNA analysis of the comprehensive heteroplasmy landscape in single human oocytes. Unappreciated levels of rare heteroplasmic variants well below the detection limit of conventional methods were identified in healthy human oocytes, of which many are reported to be deleterious and associated with mitochondrial disease and cancer. Quantitative genetic linkage analysis revealed dramatic shifts of variant frequency and clonal expansions of large SVs during oogenesis in single-donor oocytes. iMiGseq of a single human blastoid suggested stable heteroplasmy levels during early lineage differentiation of naïve pluripotent stem cells. Therefore, our data provided new insights of mtDNA genetics and laid a foundation for understanding mtDNA heteroplasmy at early stages of life.


Assuntos
DNA Mitocondrial , Células-Tronco Pluripotentes , Humanos , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Haplótipos , Heteroplasmia , Mitocôndrias/genética , Mitocôndrias/metabolismo , Oócitos/metabolismo , Células-Tronco Pluripotentes/metabolismo
5.
Nucleic Acids Res ; 51(8): e48, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-36999592

RESUMO

The ontogeny and dynamics of mtDNA heteroplasmy remain unclear due to limitations of current mtDNA sequencing methods. We developed individual Mitochondrial Genome sequencing (iMiGseq) of full-length mtDNA for ultra-sensitive variant detection, complete haplotyping, and unbiased evaluation of heteroplasmy levels, all at the individual mtDNA molecule level. iMiGseq uncovered unappreciated levels of heteroplasmic variants in single cells well below the conventional NGS detection limit and provided accurate quantitation of heteroplasmy level. iMiGseq resolved the complete haplotype of individual mtDNA in single oocytes and revealed genetic linkage of de novo mutations. iMiGseq detected sequential acquisition of detrimental mutations, including large deletions, in defective mtDNA in NARP/Leigh syndrome patient-derived induced pluripotent stem cells. iMiGseq identified unintended heteroplasmy shifts in mitoTALEN editing, while showing no appreciable level of unintended mutations in DdCBE-mediated mtDNA base editing. Therefore, iMiGseq could not only help elucidate the mitochondrial etiology of diseases, but also evaluate the safety of various mtDNA editing strategies.


Assuntos
DNA Mitocondrial , Genoma Mitocondrial , DNA Mitocondrial/genética , Heteroplasmia/genética , Genoma Mitocondrial/genética , Mitocôndrias/genética , Mutação
6.
Nano Lett ; 24(10): 3044-3050, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38437632

RESUMO

Lithium (Li) metal stands as a promising anode in advancing high-energy-density batteries. However, intrinsic issues associated with metallic Li, especially the dendritic growth, have hindered its practical application. Herein, we focus on molecular combined structural design to develop dendrite-free anodes. Specifically, using hydrogen-substituted graphdiyne (HGDY) aerogel hosts, we successfully fabricated a promising Li composite anode (Li@HGDY). The HGDY aerogel's lithiophilic nature and hierarchical pores drive molten Li infusion and reduce local current density within the three-dimensional HGDY host. The unique molecular structure of HGDY provides favorable bulk pathways for lithium-ion transport. By simultaneous regulation of electron and ion transport within the HGDY host, uniform lithium stripping/platting is fulfilled. Li@HGDY symmetric cells exhibit a low overpotential and stable cycling. The Li@HGDY||lithium iron phosphate full cell retained 98.1% capacity after 170 cycles at 0.4 C. This study sheds new light on designing high-capacity and long-lasting lithium metal anodes.

7.
J Am Chem Soc ; 146(34): 24150-24157, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39141782

RESUMO

This work introduces a new strategy of a single-atom nest catalyst, whereby several single atoms are positioned closely, aiming to achieve the dual benefits of high atom-utilization efficiency while avoiding the steric hindrance in the coupling reaction. As a proof of concept, Pt single-atom nests, where the adjacent Pt single atoms are approximately 4 Å apart, are precisely engineered on the TiO2 photocatalyst for photocatalytic non-oxidative coupling of methane. The Pt single-atom nest photocatalyst demonstrates remarkable activity, achieving a C2H6 yield and turnover frequency of 251.6 µmol gcat-1 h-1 and 20 h-1, respectively, representing a 3.2-fold improvement compared to the Pt single-atom photocatalyst. Density functional theory calculations reveal that the Pt single-atom nest can significantly decrease the energy barrier for the activation of both CH4 molecules in the coupling process.

8.
Anal Chem ; 96(26): 10738-10747, 2024 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-38898770

RESUMO

Herein, CsPbBr3 perovskite quantum dots (CPB PQDs)@poly(methyl methacrylate) (PMMA) (CPB@PMMA) nanospheres were used as energy donors with high Förster resonance energy transfer (FRET) efficiency and exceptional biocompatibility for ultrasensitive dynamic imaging of tiny amounts of microRNAs in living cells. Impressively, compared with traditional homogeneous single QDs as energy donors, CPB@PMMA obtained by encapsulating numerous CPB PQDs into PMMA as energy donors could not only significantly increase the efficiency of FRET via improving the local concentration of CPB PQDs but also distinctly avoid the problem of cytotoxicity caused by divulged heavy metal ions entering living cells. Most importantly, in the presence of target miRNA-21, DNA dendrimer-like nanostructures labeled with 6-carboxy-tetramethylrhodamine (TAMRA) were generated by the exposed tether interhybridization of the Y-shape structure, which could wrap around the surface of CPB@PMMA nanospheres to remarkably bridge the distance of FRET and increase the opportunity for effective energy transfer, resulting in excellent precision and accuracy for ultrasensitive and dynamic imaging of miRNAs. As proof of concept, the proposed strategy exhibited ultrahigh sensitivity with a detection limit of 45.3 aM and distinctly distinguished drug-irritative miRNA concentration abnormalities with living cells. Hence, the proposed enzyme-free CPB@PMMA biosensor provides convincing evidence for supplying accurate information, which could be expected to be a powerful tool for bioanalysis, diagnosis, and prognosis of human diseases.


Assuntos
Transferência Ressonante de Energia de Fluorescência , MicroRNAs , Óxidos , Pontos Quânticos , Titânio , Pontos Quânticos/química , MicroRNAs/análise , Humanos , Titânio/química , Óxidos/química , Compostos de Cálcio/química , Polimetil Metacrilato/química , Chumbo/química , Chumbo/análise , Gadolínio/química
9.
Anal Chem ; 96(26): 10809-10816, 2024 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-38886176

RESUMO

Ru-based electrochemiluminescence (ECL) coordination polymers are widely employed for bioanalysis and medical diagnosis. However, commonly used Ru-based coordination polymers face the limitation of low efficiency due to the long distance between the ECL reagent and the coreactant dispersed in detecting solution. Herein, we report a dual-ligand self-enhanced ECL coordination polymer, composed of tris(4,4'-dicarboxylic acid-2,2'-bipyridyl) ruthenium(II) dichloride (Ru(dcbpy)32+) as ECL reactant ligand and ethylenediamine (EDA) as corresponding coreactant ligand into Zn2+ metal node, termed Zn-Ru-EDA. Zn-Ru-EDA shows excellent ECL performance which is attributed to the effective intramolecular electron transport between the two ligands. Furthermore, the dual-ligand polymer allows an anodic low excitation potential (+1.09 V) luminescence. The shift in the energy level of the highest occupied molecular orbital (HOMO) upward after the synthesis of the Zn-Ru-EDA has resulted in a reduced excitation potential. The low excitation potential reduced biomolecular damage and the destruction of the modified electrodes. The ECL biosensor has been constructed using Zn-Ru-EDA with high ECL efficiency for the ultrasensitive detection of a bacterial infection and sepsis biomarker, procalcitonin (PCT), in the range from 1.00 × 10-6 to 1.00 × 10 ng·mL-1 with outstanding selectivity, and the detection limit was as low as 0.47 fg·mL-1. Collectively, the dual-ligand-based self-enhanced polymer may provide an ideal strategy for high ECL efficiency improvement as well as designing new self-enhanced multiple-ligand-based coordination in sensitive biomolecular detection for early disease diagnostics.


Assuntos
Técnicas Eletroquímicas , Medições Luminescentes , Polímeros , Pró-Calcitonina , Rutênio , Ligantes , Polímeros/química , Pró-Calcitonina/sangue , Pró-Calcitonina/análise , Humanos , Rutênio/química , Complexos de Coordenação/química , Limite de Detecção , Técnicas Biossensoriais , Etilenodiaminas/química
10.
FASEB J ; 37(4): e22840, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36943397

RESUMO

Erdafitinib is a novel fibroblast growth factor receptor (FGFR) inhibitor that has shown great therapeutic promise for solid tumor patients with FGFR3 alterations, especially in urothelial carcinoma. However, the mechanisms of resistance to FGFR inhibitors remain poorly understood. In this study, we found Erdafitinib could kill cells by inducing incomplete autophagy and increasing intracellular reactive oxygen species levels. We have established an Erdafitinib-resistant cell line, RT-112-RS. whole transcriptome RNA sequencing (RNA-Seq) and Cytospace analysis performed on Erdafitinib-resistant RT-112-RS cells and parental RT-112 cells introduced P4HA2 as a linchpin to Erdafitinib resistance. The gain and loss of function study provided evidence for P4HA2 conferring such resistance in RT-112 cells. Furthermore, P4HA2 could stabilize the HIF-1α protein which then activated downstream target genes to reduce reactive oxygen species levels in bladder cancer. In turn, HIF-1α could directly bind to P4HA2 promoter, indicating a positive loop between P4HA2 and HIF-1α in bladder cancer. These results suggest a substantial role of P4HA2 in mediating acquired resistance to Erdafitinib and provide a potential target for bladder cancer treatment.


Assuntos
Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Humanos , Carcinoma de Células de Transição/tratamento farmacológico , Carcinoma de Células de Transição/genética , Carcinoma de Células de Transição/patologia , Linhagem Celular Tumoral , Pirazóis/farmacologia , Espécies Reativas de Oxigênio , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia
11.
Neurochem Res ; 49(3): 660-669, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38010603

RESUMO

Hexavalent chromium (Cr (VI)), one of the most detrimental pollutants, has been ubiquitously present in the environment and causes serious toxicity to humans, such as hepatotoxicity, nephrotoxicity, pulmonary toxicity, and cardiotoxicity. However, Cr (VI)-induced neurotoxicity in primary neuron level has not been well explored yet. Herein, potassium dichromate (K2Cr2O7) was employed to examine the neurotoxicity of Cr (VI) in rat primary hippocampal neurons. MTT test was used to examine the neural viability. Mitochondrial dysfunction was assessed by the JC-1 probe and Mito-Tracker probe. DCFH-DA and Mito-SOX Red were utilized to evaluate the oxidative status. Bcl-2 family and MAPKs expression were investigated using Western blotting. The results demonstrated that Cr (VI) treatment dose- and time-dependently inhibited neural viability. Mechanism investigation found that Cr (VI) treatment causes mitochondrial dysfunction by affecting Bcl-2 family expression. Moreover, Cr (VI) treatment also induces intracellular reactive oxygen species (ROS) generation, DNA damage, and MAPKs activation in neurons. However, inhibition of ROS by glutathione (GSH) effectually balanced Bcl-2 family expression, attenuated DNA damage and the MAPKs activation, and eventually improved neural viability neurons. Collectively, these above results above suggest that Cr (VI) causes significant neurotoxicity by triggering mitochondrial dysfunction, ROS-mediated oxidative damage and MAKPs activation.


Assuntos
Doenças Mitocondriais , Estresse Oxidativo , Humanos , Ratos , Animais , Espécies Reativas de Oxigênio/metabolismo , Cromo/toxicidade , Glutationa/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
12.
Langmuir ; 40(1): 604-613, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38108826

RESUMO

Non-noble metal photothermal materials have recently attracted increasing attention as unique alternatives to noble metal-based ones due to advantages like earth abundance, cost-effectiveness, and large-scale application capability. In this study, hierarchical copper sulfide (CuS) nanostructures with tunable flower-like morphologies and dimensional sizes are prepared via a fatty amine-mediated one-pot polyol synthesis. In particular, the addition of fatty amines induces a significant decrease in the overall particle size and lamellar thickness, and their morphologies and sizes could be tuned using different types of fatty amines. The dense stacking of nanosheets with limited sizes in the form of such a unique hierarchical architecture facilitates the interactions of the electromagnetic fields between adjacent nanoplates and enables the creation of abundant hot-spot regions, thus, benefiting the enhanced second near-infrared (NIR-II) light absorptions. The optimized CuS nanoflowers exhibit a photothermal conversion efficiency of 37.6%, realizing a temperature increase of nearly 50 °C within 10 min under 1064 nm laser irradiations at a power density of 1 W cm-2. They also exhibit broad-spectrum antibacterial activity, rendering them promising candidates for combating a spectrum of bacterial infections. The present study offers a feasible strategy to generate nanosheet-based hierarchical CuS nanostructures and validates their promising use in photothermal conversion, which could find important use in NIR-II photothermal therapy.


Assuntos
Cobre , Nanoestruturas , Cobre/farmacologia , Cobre/química , Nanoestruturas/química , Sulfetos/farmacologia , Sulfetos/química , Antibacterianos/farmacologia , Aminas , Fototerapia
13.
Soft Matter ; 20(5): 1061-1069, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38206109

RESUMO

Liquid metal particulate composites (LMPCs) are super-stretchable conductors with promising applications in soft electronics. Their conductance originates from the percolation networks of liquid metal particles. This work aims at elucidating the effect of finite-size and sample shape on the percolation and electromechanical properties of LMPCs, given that their dimensions range from microns to centimeters. It is found that their percolation threshold is dominated by the smallest dimension of the samples, not the shape or aspect ratio. A smaller sample size increases the percolation threshold and makes it harder to activate the conductance. In addition, smaller samples are more sensitive to local defects, which adversely impair the electromechanical properties or even undermine the conductance. Finally, this work considers the influence of finite-size on the piezoresistance effect, i.e., strain-dependent resistance. It is found that the piezoresistance effect and finite-size effect are uncorrelated, if the samples are above the percolation threshold. The findings provide not only fundamental insights on the finite-size effect of percolation but also guidance on the design-fabrication process for LMPCs to achieve more reliable electromechanical performance.

14.
Mol Biol Rep ; 51(1): 808, 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39002003

RESUMO

BACKGROUND: Endothelial cells (ECs) can confer neuroprotection by secreting molecules. This study aimed to investigate whether DNA methylation contributes to the neuroprotective gene expression induced by hypoxia preconditioning (HPC) in ECs and to clarify that the secretion of molecules from HPC ECs may be one of the molecular mechanisms of neuroprotection. METHODS: Human microvascular endothelial cell-1 (HMEC-1) was cultured under normal conditions (C), hypoxia(H), and hypoxia preconditioning (HPC), followed by the isolation of culture medium (CM). SY5Y cell incubated with the isolated CM from HMEC-1 was exposed to oxygen-glucose deprivation (OGD). The DNA methyltransferases (DNMTs), global methylation level, miR-126 and its promotor DNA methylation level in HMEC-1 were measured. The cell viability and cell injury in SY5Y were detected. RESULTS: HPC decreased DNMTs level and global methylation level as well as increased miR-126 expression in HMEC-1. CM from HPC treated HMEC-1 also relieved SY5Y cell damage, while CM from HMEC-1 which over-expression of miR-126 can reduce injury in SY5Y under OGD condition. CONCLUSIONS: These findings indicate EC may secrete molecules, such as miR-126, to execute neuroprotection induced by HPC through regulating the expression of DNMTs.


Assuntos
Hipóxia Celular , Metilação de DNA , Células Endoteliais , MicroRNAs , Neurônios , MicroRNAs/genética , MicroRNAs/metabolismo , Metilação de DNA/genética , Humanos , Células Endoteliais/metabolismo , Hipóxia Celular/genética , Neurônios/metabolismo , Regulação para Cima/genética , Sobrevivência Celular/genética , Glucose/metabolismo , Linhagem Celular , Oxigênio/metabolismo , Regiões Promotoras Genéticas/genética
15.
Arch Insect Biochem Physiol ; 115(1): e22070, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38288484

RESUMO

DNA barcoding is a useful addition to the traditional morphology-based taxonomy. A ca. 650 bp fragment of the 5' end of mitochondrial cytochrome c oxidase subunit I (hereafter COI-5P) DNA barcoding was sued as a practical tool for Gampsocleis species identification. DNA barcodes from 889 specimens belonging to 8 putative Gampsocleis species was analyzed, including 687 newly generated DNA barcodes. These barcode sequences were clustered/grouped into Operational Taxonomic Units (OTUs) using the criteria of five algorithms, namely Barcode Index Number (BIN) System, Assemble Species by Automatic Partitioning (ASAP), a Java program uses an explicit, determinate algorithm to define Molecular Operational Taxonomic Unit (jMOTU), Generalized Mixed Yule Coalescent (GMYC), and Bayesian implementation of the Poisson Tree Processes model (bPTP). The Taxon ID Tree grouped sequences of morphospecies and almost all MOTUs in distinct nonoverlapping clusters. Both long- and short-winged Gampsocleis species are reciprocally monophyletic in the Taxon ID Tree. In BOLD, 889 barcode sequences are assigned to 17 BINs. The algorithms ASAP, jMOTU, bPTP and GMYC clustered the barcode sequences into 6, 13, 10, and 23 MOTUs, respectively. BIN, ASAP, and bPTP algorithm placed three long-winged species, G. sedakovii, G. sinensis and G. ussuriensis within the same MOTU. All species delimitation algorithms split two short-winged species,G. fletcheri and G. gratiosa into at least two MOTUs each, except for ASAP algorithm. More detailed molecular and morphological integrative studies are required to clarify the status of these MOTUs in the future.


Assuntos
Código de Barras de DNA Taxonômico , Ortópteros , Animais , Teorema de Bayes , Ortópteros/genética , Filogenia , DNA
16.
Mol Cell ; 62(3): 359-370, 2016 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-27153534

RESUMO

Metabolic reprogramming is fundamental to biological homeostasis, enabling cells to adjust metabolic routes after sensing altered availability of fuels and growth factors. ULK1 and ULK2 represent key integrators that relay metabolic stress signals to the autophagy machinery. Here, we demonstrate that, during deprivation of amino acid and growth factors, ULK1/2 directly phosphorylate key glycolytic enzymes including hexokinase (HK), phosphofructokinase 1 (PFK1), enolase 1 (ENO1), and the gluconeogenic enzyme fructose-1,6-bisphosphatase (FBP1). Phosphorylation of these enzymes leads to enhanced HK activity to sustain glucose uptake but reduced activity of FBP1 to block the gluconeogenic route and reduced activity of PFK1 and ENO1 to moderate drop of glucose-6-phosphate and to repartition more carbon flux to pentose phosphate pathway (PPP), maintaining cellular energy and redox homeostasis at cellular and organismal levels. These results identify ULK1/2 as a bifurcate-signaling node that sustains glucose metabolic fluxes besides initiation of autophagy in response to nutritional deprivation.


Assuntos
Proteína Homóloga à Proteína-1 Relacionada à Autofagia/metabolismo , Autofagia , Glucose/metabolismo , Glicólise , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Via de Pentose Fosfato , Proteínas Serina-Treonina Quinases/metabolismo , Estresse Fisiológico , Aminoácidos/deficiência , Aminoácidos/metabolismo , Animais , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/deficiência , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/genética , Biomarcadores Tumorais/metabolismo , Morte Celular , Proteínas de Ligação a DNA/metabolismo , Feminino , Frutose-Bifosfatase/metabolismo , Genótipo , Células HCT116 , Hexoquinase/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Células MCF-7 , Masculino , Camundongos Knockout , Fenótipo , Fosfofrutoquinase-1/metabolismo , Fosfopiruvato Hidratase/metabolismo , Fosforilação , Proteínas Serina-Treonina Quinases/deficiência , Proteínas Serina-Treonina Quinases/genética , Interferência de RNA , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Fatores de Tempo , Transfecção , Proteínas Supressoras de Tumor/metabolismo
17.
J Nanobiotechnology ; 22(1): 560, 2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39272197

RESUMO

Intravesical therapy (IT) is widely used to tackle various urological diseases. However, its clinical efficacy is decreased by the impermeability of various barriers presented on the bladder luminal surface, including the urinary mucus layer and the densely packed tissue barrier. In this study, we report a mucoadhesive-to-penetrating nanomotors-in-hydrogel system for urothelium-oriented intravesical drug delivery. Upon intravesical instillation, its poloxamer 407 (PLX) hydrogel gelated and adhered to the urothelium to prolong its intravesical retention. The urea afterwards diffused into the hydrogel, thus generating a concentration gradient. Urease-powered membrane nanomotors (UMN) without asymmetric surface engineering could catalyze the urea and migrate down this concentration gradient to deeply and unidirectionally penetrate the urothelial barrier. Moreover, the intravesical hybrid system-delivered gemcitabine could effectively inhibit the bladder tumor growth without inducing any side effect. Therefore, our mucoadhesive-to-penetrating nanomotors-in-hydrogel system could serve as an alternative to IT to meet the clinical need for more efficacious therapeutics for urological diseases.


Assuntos
Sistemas de Liberação de Medicamentos , Hidrogéis , Poloxâmero , Neoplasias da Bexiga Urinária , Urotélio , Urotélio/metabolismo , Animais , Hidrogéis/química , Sistemas de Liberação de Medicamentos/métodos , Administração Intravesical , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/metabolismo , Camundongos , Poloxâmero/química , Desoxicitidina/análogos & derivados , Desoxicitidina/química , Desoxicitidina/administração & dosagem , Gencitabina , Bexiga Urinária/metabolismo , Humanos , Feminino , Linhagem Celular Tumoral , Adesividade
18.
Int J Neurosci ; : 1-17, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38744296

RESUMO

OBJECTIVE: In light of the increasing importance of immunotherapy in bladder cancer treatment, this study is aim to investigate the expression and clinical significance of programmed cell surface death-1 (PD-1) in bladder cancer patients without lymph node metastasis, and to compare and analyze the difference of PD-1 in draining lymph nodes and tumor tissues. METHODS: The expression of PD-1 on T cells and the proportion of positive PD-1 + T cells of IFN-γ and CD105a were detected by flow cytometry, and the correlation between PD-1 expression and clinical parameters was analyzed. RESULTS: The percentage of PD-1 positive cells in drainage lymph nodes was higher than that in tumor tissues (P < 0.001). PD-1 positive cells accounted for the highest proportion in CD3 + T cells. The proportion of IFN-γ-positive PD-1 + T cells in draining lymph nodes was significantly higher than that in tumor tissues (P < 0.001), while there was no significant difference in CD105a positive PD-1 + T cells between tumor tissues and draining lymph nodes. Pathological grade, tumor size and stage were positively correlated with PD-1 expression level in the lymph nodes. CONCLUSION: The high expression of PD-1 in patients with bladder cancer without lymph node metastasis, especially in draining lymph nodes, suggests that PD-1 may play a key role in the regulation of tumor immune microenvironment. The correlation between PD-1 and clinical parameters indicates its potential prognostic value. These findings provide important clinical implications for PD-1 targeted therapy, but further prospective studies are needed to determine the application value of PD-1 in therapeutic strategies.

19.
J Asian Nat Prod Res ; : 1-10, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39120438

RESUMO

Four new homoisoflavonoids, 7-hydroxy-3-[hydroxy(4'-methoxyphenyl)methyl]-benzopyran-4-one (1), (3R)-7, 8-dihydroxy-3-(4'-methoxybenzyl)-chroman-4-one (2), 7-hydroxy-3-(2'-hydroxy-4'-methoxybenzyl)-chroman-4-one (3), and 7-hydroxy-3-(2'-hydroxy-4'-methoxybenzyl)-benzopyran-4-one (4), were isolated from the seeds of Caesalpinia pulcherrima. The structures of new compounds were elucidated by MS and NMR spectra. Their absolute configurations were assigned using electronic circular dichroism spectrum. Compounds 2 and 4 exhibited cytotoxic effects on MCF-7/TAM cells with the IC50 values of 101.4 ± 0.03 and 93.02 ± 0.03 µM, respectively.

20.
Nano Lett ; 23(13): 5967-5974, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37350461

RESUMO

Lithium-sulfur (Li-S) batteries are promising candidates for next-generation energy storage systems due to their high theoretical energy density and the low cost of sulfur. However, slow conversion kinetics between the insulating S and lithium sulfide (Li2S) remains as a technical challenge. In this work, we report a catalyst featuring nickel (Ni) single atoms and clusters anchored to a porous hydrogen-substituted graphdiyne support (termed Ni@HGDY), which is incorporated in Li2S cathodes. The rapidly synthesized catalyst was found to enhance ionic and electronic conductivity, decrease the reaction overpotential, and promote more complete conversion between Li2S and sulfur. The addition of Ni@HGDY to commercial Li2S powder enabled a capacity of over 516 mAh gLi2S-1 at 1 C for over 125 cycles, whereas the control Li2S cathode managed to maintain just over 200 mAh gLi2S-1. These findings highlight the efficacy of Ni as a metal catalyst and demonstrate the promise of HGDY in energy storage devices.

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