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Fibroblasts are important regulators of inflammation, but whether fibroblasts change phenotype during resolution of inflammation is not clear. Here we use positron emission tomography to detect fibroblast activation protein (FAP) as a means to visualize fibroblast activation in vivo during inflammation in humans. While tracer accumulation is high in active arthritis, it decreases after tumor necrosis factor and interleukin-17A inhibition. Biopsy-based single-cell RNA-sequencing analyses in experimental arthritis show that FAP signal reduction reflects a phenotypic switch from pro-inflammatory MMP3+/IL6+ fibroblasts (high FAP internalization) to pro-resolving CD200+DKK3+ fibroblasts (low FAP internalization). Spatial transcriptomics of human joints indicates that pro-resolving niches of CD200+DKK3+ fibroblasts cluster with type 2 innate lymphoid cells, whereas MMP3+/IL6+ fibroblasts colocalize with inflammatory immune cells. CD200+DKK3+ fibroblasts stabilized the type 2 innate lymphoid cell phenotype and induced resolution of arthritis via CD200-CD200R1 signaling. Taken together, these data suggest a dynamic molecular regulation of the mesenchymal compartment during resolution of inflammation.
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Artritis , Inmunidad Innata , Humanos , Metaloproteinasa 3 de la Matriz , Interleucina-6/metabolismo , Linfocitos/metabolismo , Inflamación/metabolismo , Fibroblastos/metabolismoRESUMEN
Ex vivo expansion of satellite cells and directed differentiation of pluripotent cells to mature skeletal muscle have proved difficult challenges for regenerative biology. Using a zebrafish embryo culture system with reporters of early and late skeletal muscle differentiation, we examined the influence of 2,400 chemicals on myogenesis and identified six that expanded muscle progenitors, including three GSK3ß inhibitors, two calpain inhibitors, and one adenylyl cyclase activator, forskolin. Forskolin also enhanced proliferation of mouse satellite cells in culture and maintained their ability to engraft muscle in vivo. A combination of bFGF, forskolin, and the GSK3ß inhibitor BIO induced skeletal muscle differentiation in human induced pluripotent stem cells (iPSCs) and produced engraftable myogenic progenitors that contributed to muscle repair in vivo. In summary, these studies reveal functionally conserved pathways regulating myogenesis across species and identify chemical compounds that expand mouse satellite cells and differentiate human iPSCs into engraftable muscle.
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Evaluación Preclínica de Medicamentos , Desarrollo de Músculos/efectos de los fármacos , Animales , Colforsina/farmacología , Técnicas de Cultivo , AMP Cíclico/metabolismo , Células Madre Pluripotentes Inducidas/citología , Células Madre Pluripotentes Inducidas/metabolismo , Ratones , Músculo Esquelético/citología , Músculo Esquelético/fisiología , Distrofias Musculares/terapia , Células Satélite del Músculo Esquelético/metabolismo , Trasplante de Células Madre , Pez Cebra/embriología , Pez Cebra/metabolismoRESUMEN
The SARS-CoV-2 Omicron variant exhibits striking immune evasion and is spreading rapidly worldwide. Understanding the structural basis of the high transmissibility and enhanced immune evasion of Omicron is of high importance. Here, using cryo-electron microscopy, we present both the closed and the open states of the Omicron spike (S) protein, which appear more compact than the counterparts of the G614 strain1, potentially related to enhanced inter-protomer and S1-S2 interactions induced by Omicron residue substitution. The closed state showing dominant population may indicate a conformational masking mechanism for the immune evasion of Omicron. Moreover, we captured three states for the Omicron S-ACE2 complex, revealing that the substitutions on the Omicron RBM result in new salt bridges and hydrogen bonds, more favourable electrostatic surface properties, and an overall strengthened S-ACE2 interaction, in line with the observed higher ACE2 affinity of Omicron S than of G614. Furthermore, we determined the structures of Omicron S in complex with the Fab of S3H3, an antibody that is able to cross-neutralize major variants of concern including Omicron, elucidating the structural basis for S3H3-mediated broad-spectrum neutralization. Our findings shed light on the receptor engagement and antibody neutralization or evasion of Omicron and may also inform the design of broadly effective vaccines against SARS-CoV-2.
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COVID-19 , Glicoproteína de la Espiga del Coronavirus , Enzima Convertidora de Angiotensina 2 , Anticuerpos Antivirales , Vacunas contra la COVID-19 , Microscopía por Crioelectrón , Humanos , SARS-CoV-2RESUMEN
Generation of hematopoietic stem and progenitor cells (HSPCs) ex vivo and in vivo, especially the generation of safe therapeutic HSPCs, still remains inefficient. In this study, we have identified compound BF170 hydrochloride as a previously unreported pro-hematopoiesis molecule, using the differentiation assays of primary zebrafish blastomere cell culture and mouse embryoid bodies (EBs), and we demonstrate that BF170 hydrochloride promoted definitive hematopoiesis in vivo. During zebrafish definitive hematopoiesis, BF170 hydrochloride increases blood flow, expands hemogenic endothelium (HE) cells and promotes HSPC emergence. Mechanistically, the primary cilia-Ca2+-Notch/NO signaling pathway, which is downstream of the blood flow, mediated the effects of BF170 hydrochloride on HSPC induction in vivo. Our findings, for the first time, reveal that BF170 hydrochloride is a compound that enhances HSPC induction and may be applied to the ex vivo expansion of HSPCs.
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Diferenciación Celular , Hematopoyesis , Células Madre Hematopoyéticas , Pez Cebra , Animales , Células Madre Hematopoyéticas/efectos de los fármacos , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/metabolismo , Ratones , Diferenciación Celular/efectos de los fármacos , Hematopoyesis/efectos de los fármacos , Receptores Notch/metabolismo , Transducción de Señal/efectos de los fármacos , Cuerpos Embrioides/citología , Cuerpos Embrioides/efectos de los fármacos , Cuerpos Embrioides/metabolismo , Cilios/metabolismo , Cilios/efectos de los fármacos , Blastómeros/citología , Blastómeros/metabolismo , Blastómeros/efectos de los fármacos , Células CultivadasRESUMEN
The 26S proteasome is the ATP-dependent protease responsible for regulating the proteome of eukaryotic cells through degradation of mainly ubiquitin-tagged substrates. In order to understand how proteasome responds to ubiquitin signal, we resolved an ensemble of cryo-EM structures of proteasome in the presence of K48-Ub4, with three of them resolved at near-atomic resolution. We identified a conformation with stabilized ubiquitin receptors and a previously unreported orientation of the lid, assigned as a Ub-accepted state C1-b. We determined another structure C3-b with localized K48-Ub4 to the toroid region of Rpn1, assigned as a substrate-processing state. Our structures indicate that tetraUb induced conformational changes in proteasome could initiate substrate degradation. We also propose a CP gate-opening mechanism involving the propagation of the motion of the lid to the gate through the Rpn6-α2 interaction. Our results enabled us to put forward a model of a functional cycle for proteasomes induced by tetraUb and nucleotide.
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Complejo de la Endopetidasa Proteasomal/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/enzimología , Ubiquitina/metabolismo , Regulación Alostérica , Animales , Sitios de Unión , Microscopía por Crioelectrón , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Endopeptidasas/genética , Endopeptidasas/metabolismo , Humanos , Modelos Moleculares , Complejo de la Endopetidasa Proteasomal/genética , Complejo de la Endopetidasa Proteasomal/ultraestructura , Unión Proteica , Conformación Proteica , Proteolisis , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/ultraestructura , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/ultraestructura , Relación Estructura-Actividad , Ubiquitina/ultraestructura , UbiquitinaciónRESUMEN
Effective bimetallic nanoelectrocatalysis demands precise control of composition, structure, and understanding catalytic mechanisms. To address these challenges, we employ a two-in-one approach, integrating online synthesis with real-time imaging of bimetallic Au@Metal core-shell nanoparticles (Au@M NPs) via electrochemiluminescence microscopy (ECLM). Within 120 s, online electrodeposition and in situ catalytic activity screening alternate. ECLM captures transient faradaic processes during potential switches, visualizes electrochemical processes in real-time, and tracks catalytic activity dynamics at the single-particle level. Analysis using ECL photon flux density eliminates size effects and yields quantitative electrocatalytic activity results. Notably, a nonlinear activity trend corresponding to the shell metal to Au surface atomic ratio is discerned, quantifying the optimal surface component ratio of Au@M NPs. This approach offers a comprehensive understanding of catalytic behavior during the deposition process with high spatiotemporal resolution, which is crucial for tailoring efficient bimetallic nanocatalysts for diverse applications.
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Lower olefins are widely used in the chemical industry as basic carbon-based feedstocks. Here, we report the catalytic system featuring isolated single-atom sites of iridium (Ir1) that can function within the entire temperature range of 300-600 °C and transform alkanes with conversions close to thermodynamics-dictated levels. The high turnover frequency values of the Ir1 system are comparable to those of homogeneous catalytic reactions. Experimental data and theoretical calculations both indicate that Ir1 is the primary catalytic site, while the coordinating C and N atoms help to enhance the activity and stability, respectively; all three kinds of elements cooperatively contribute to the high performance of this novel active site. We have further immobilized this catalyst on particulate Al2O3, and we found that the resulting composite system under mimicked industrial conditions could still give high catalytic performances; in addition, we have also developed and established a new scheme of periodical in situ regeneration specifically for this composite particulate catalyst.
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BACKGROUND: Adhesion G protein-coupled receptors (aGPCRs), a distinctive subset of the G protein-coupled receptor (GPCR) superfamily, play crucial roles in various physiological and pathological processes, with implications in tumor development. Despite the global prevalence of breast cancer (BRCA), specific aGPCRs as potential drug targets or biomarkers remain underexplored. METHODS: UALCAN, GEPIA, Kaplan-Meier Plotter, MethSurv, cBiopportal, String, GeneMANIA, DAVID, Timer, Metascape, and qPCR were applied in this work. RESULTS: Our analysis revealed significantly increased transcriptional levels of ADGRB2, ADGRC1, ADGRC2, ADGRC3, ADGRE1, ADGRF2, ADGRF4, and ADGRL1 in BRCA primary tumors. Further analysis indicated a significant correlation between the expressions of certain aGPCRs and the pathological stage of BRCA. High expression of ADGRA1, ADGRF2, ADGRF4, ADGRG1, ADGRG2, ADGRG4, ADGRG6, and ADGRG7 was significantly correlated with poor overall survival (OS) in BRCA patients. Additionally, high expression of ADGRF2 and ADGRF4 indicated inferior recurrence-free survival (RFS) in BRCA patients. The RT-qPCR experiments also confirmed that the mRNA levels of ADGRF2 and ADGRF4 were higher in BRCA cells and tissues. Functional analysis highlighted the diverse roles of aGPCRs, encompassing GPCR signaling and metabolic energy reserves. Moreover, aGPCRs may exert influence or actively participate in the development of BRCA through their impact on immune status. CONCLUSION: aGPCRs, particularly ADGRF2 and ADGRF4, hold promise as immunotherapeutic targets and prognostic biomarkers in BRCA.
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Biomarcadores de Tumor , Neoplasias de la Mama , Regulación Neoplásica de la Expresión Génica , Receptores Acoplados a Proteínas G , Humanos , Femenino , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/mortalidad , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética , Biomarcadores de Tumor/metabolismo , Biomarcadores de Tumor/genética , Pronóstico , Terapia Molecular Dirigida , Línea Celular Tumoral , Perfilación de la Expresión Génica , Estimación de Kaplan-MeierRESUMEN
Developing multifunctional, stimuli-responsive nanomedicine is intriguing because it has the potential to effectively treat cancer. Yet, poor tumor penetration of nanodrugs results in limited antitumor efficacy. Herein, an oxygen-driven silicon-based nanomotor (Si-motor) loaded with MnO and CaO2 nanoparticles is developed, which can move in tumor microenvironment (TME) by the cascade reaction of CaO2 and MnO. Under acidic TME, CaO2 reacts with acid to release Ca2+ to induce mitochondrial damage and simultaneously produces O2 and H2O2, when the loaded MnO exerts Fenton-like activity to produce ·OH and O2 based on the produced H2O2. The generated O2 drives Si-motor forward, thus endowing active delivery capability of the formed motors in TME. Meanwhile, MnO with glutathione (GSH) depletion ability further prevents reactive oxygen species (ROS) from being destroyed. Such TME actuated Si-motor with enhanced cellular uptake and deep penetration provides amplification of synergistic oxidative stresscaused by intracellular Ca2 + overloading, GSH depletion induced by Mn2+, and Mn2+ mediated chemodynamic treatment (CDT), leading to excellent tumor cell death. The created nanomotor may offer an effective platform for active synergistic cancer treatment.
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Strain engineering has been widely used to optimize platinum-based oxygen reduction reaction (ORR) catalysts for proton exchange membrane fuel cells (PEMFCs). PtM3 (M is base metals), a well-known high-compressive-strain intermetallic alloy, shows promise as a low platinum ORR catalyst due to high intrinsic activity. However, during the alloying of Pt with a threefold amount of M, a notable phase separation between Pt and M may occur, with M particles rapidly sintering while Pt particles grow slowly, posing a challenge in achieving a well-defined PtM3 intermetallic alloy. Here, an entropy-driven Ostwald ripening reversal phenomenon is discovered that enables the synthesis of small-sized Pt(FeCoNiCu)3 intermetallic ORR catalysts. High entropy promotes the thermodynamic driving force for the alloying Pt with M, which triggers the Ostwald ripening reversal of sintered FeCoNiCu particles and facilitates the formation of uniform Pt(FeCoNiCu)3 intermetallic catalysts. The prepared Pt(FeCoNiCu)3 catalysts exhibit a high specific activity of 3.82 mA cm-2, along with a power density of ≈1.3 W cm-2 at 0.67 V and 94 °C with a cathode Pt loading of 0.1 mg cm-2 in H2-air fuel cell.
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Nanotechnology-based strategy has recently drawn extensive attention for the therapy of malignant tumors due to its distinct strengths in cancer diagnosis and treatment. However, the limited intratumoral permeability of nanoparticles is a major hurdle to achieving the desired effect of cancer treatment. Due to their superior cargo towing and reliable penetrating property, micro-/nanomotors (MNMs) are considered as one of the most potential candidates for the coming generation of drug delivery platforms. Here, near-infrared (NIR)-actuated biomimetic nanomotors (4T1-JPGSs-IND) are fabricated successfully and we demonstrate that 4T1-JPGSs-IND selectively accumulate in homologous tumor regions due to the effective homing ability. Upon laser irradiation, hyperthermia generated by 4T1-JPGSs-IND leads to self-thermophoretic motion and photothermal therapy (PTT) to ablate tumors with a deep depth, thereby improving the photothermal therapeutic effect for cancer management. The developed nanomotor system with multifunctionalities exhibits promising potential in biomedical applications to fight against various diseases.
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Hipertermia Inducida , Nanopartículas , Neoplasias , Humanos , Terapia Fototérmica , Fototerapia , Biomimética , Neoplasias/terapia , Línea Celular TumoralRESUMEN
BACKGROUND AND AIMS: In the treatment of chronic hepatitis B (CHB) infection, stimulation of innate immunity may lead to hepatitis B virus (HBV) cure. Alpha-kinase 1 (ALPK1) is a pattern recognition receptor (PRR) that activates the NF-κB pathway and stimulates innate immunity. Here we characterized the preclinical anti-HBV efficacy of DF-006, an orally active agonist of ALPK1 currently in clinical development for CHB. APPROACH AND RESULTS: In adeno-associated virus (AAV)-HBV mouse models and primary human hepatocytes (PHHs) infected with HBV, we evaluated the antiviral efficacy of DF-006. In the mouse models, DF-006 rapidly reduced serum HBV DNA, hepatitis B surface antigen, and hepatitis B e antigen levels using doses as low as 0.08 µg/kg, 1 µg/kg, and 5 µg/kg, respectively. DF-006 in combination with the HBV nucleoside reverse transcriptase inhibitor, entecavir, further reduced HBV DNA. Antiviral efficacy in mice was associated with an increase in immune cell infiltration and decrease of hepatitis B core antigen, encapsidated pregenomic RNA, and covalently closed circular DNA in liver. At subnanomolar concentrations, DF-006 also showed anti-HBV efficacy in PHH with significant reductions of HBV DNA. Following dosing with DF-006, there was upregulation of NF-κB-targeted genes that are involved in innate immunity. CONCLUSION: DF-006 was efficacious in mouse and PHH models of HBV without any indications of overt toxicity. In mice, DF-006 localized primarily to the liver where it potently activated innate immunity. The transcriptional response in mouse liver provides insights into mechanisms that mediate anti-HBV efficacy by DF-006.
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Hepatitis B Crónica , Hepatitis B , Humanos , Ratones , Animales , ADN Viral , FN-kappa B/metabolismo , Hepatocitos/metabolismo , Virus de la Hepatitis B/genética , Antivirales/farmacología , Antivirales/uso terapéuticoRESUMEN
Tacrolimus (TAC)-induced renal injury is detrimental to long-term kidney function, but a treatment medication is not available. Glycyrrhizic acid (GA) is an active ingredient in licorice widely used to treat kidney disease. Thus, this study explored the mechanisms of renoprotection by GA on TAC-induced renal injury. C57BL/6 mice were subjected daily to TAC or a combination of TAC and GA for 4 weeks, and then renal function, histopathology, and autophagy were assessed to examine the effect of GA on a renal injury. Next, Human kidney proximal tubular epithelial (HK-2) cells were pretreated with GA for 2 h and then treated with TAC for 24 h. The effect of GA on TAC-induced HK-2 cell injury was assessed by measuring cell viability, apoptosis, autophagy, and lysosomes. Mice exposed to TAC and treated with GA had significantly greater improvements in renal function and tubulointerstitial fibrosis in comparison to mice not treated with GA. In addition, fibrosis-related protein expression, including α-smooth muscle actin and fibronectin, decreased after GA treatment. GA treatment also relieved autophagic clearance in TAC-induced renal injury. Several in vitro studies found that TAC inhibited cell viability, autophagy, lysosomal acidification, and promoted apoptosis. However, these results were less pronounced with GA pretreatment. In addition, bafilomycin A1 (which inhibits lysosomal function) reduced the protective effect of GA, indicating that lysosomal function plays an important role in this effect. Our data suggest that GA improves lysosomal function and regulates autophagy to protect against TAC-induced renal injury.
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Enfermedades Renales , Tacrolimus , Ratones , Humanos , Animales , Tacrolimus/farmacología , Ácido Glicirrínico/metabolismo , Ácido Glicirrínico/farmacología , Ratones Endogámicos C57BL , Riñón/metabolismo , Autofagia , Enfermedades Renales/patologíaRESUMEN
The highly diverse microbial ecosystem of the human body colonizes the gastrointestinal tract has a profound impact on the host's immune, metabolic, endocrine, and other physiological processes, which are all interconnected. Specifically, gut microbiota has been found to play a crucial role in facilitating the adaptation and initiation of immune regulatory response through the gastrointestinal tract affecting the other distal mucosal sites such as lungs. A tightly regulated lung-gut axis during respiratory ailments may influence the various molecular patterns that instructs priming the disease severity to dysregulate the normal function. This review provides a comprehensive summary of current research on gut microbiota dysbiosis in respiratory diseases including asthma, pneumonia, bronchopneumonia, COPD during infections and cancer. A complex-interaction among gut microbiome, associated metabolites, cytokines, and chemokines regulates the protective immune response activating the mucosal humoral and cellular response. This potential mechanism bridges the regulation patterns through the gut-lung axis. This paper aims to advance the understanding of the crosstalk of gut-lung microbiome during infection, could lead to strategize to modulate the gut microbiome as a treatment plan to improve bad prognosis in various respiratory diseases.
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Microbioma Gastrointestinal , Microbiota , Enfermedades Respiratorias , Humanos , Citocinas , PulmónRESUMEN
Liver fibrosis is a determinant-stage process of many chronic liver diseases and affected over 7.9 billion populations worldwide with increasing demands of ideal therapeutic agents. Discovery of active molecules with anti-hepatic fibrosis efficacies presents the most attacking filed. Here, we revealed that hepatic L-aspartate levels were decreased in CCl4-induced fibrotic mice. Instead, supplementation of L-aspartate orally alleviated typical manifestations of liver injury and fibrosis. These therapeutic efficacies were alongside improvements of mitochondrial adaptive oxidation. Notably, treatment with L-aspartate rebalanced hepatic cholesterol-steroid metabolism and reduced the levels of liver-impairing metabolites, including corticosterone (CORT). Mechanistically, L-aspartate treatment efficiently reversed CORT-mediated glucocorticoid receptor ß (GRß) signaling activation and subsequent transcriptional suppression of the mitochondrial genome by directly binding to the mitochondrial genome. Knockout of GRß ameliorated corticosterone-mediated mitochondrial dysfunction and hepatocyte damage which also weakened the improvements of L-aspartate in suppressing GRß signaling. These data suggest that L-aspartate ameliorates hepatic fibrosis by suppressing GRß signaling via rebalancing cholesterol-steroid metabolism, would be an ideal candidate for clinical liver fibrosis treatment.
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Ácido Aspártico , Tetracloruro de Carbono , Cirrosis Hepática , Hígado , Ratones Endogámicos C57BL , Receptores de Glucocorticoides , Animales , Receptores de Glucocorticoides/metabolismo , Receptores de Glucocorticoides/genética , Masculino , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/inducido químicamente , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Ácido Aspártico/metabolismo , Ratones , Corticosterona , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Colesterol/metabolismo , Transducción de Señal/efectos de los fármacos , Mitocondrias Hepáticas/metabolismo , Mitocondrias Hepáticas/efectos de los fármacos , Mitocondrias Hepáticas/patología , Ratones NoqueadosRESUMEN
Lung adenocarcinoma (LUAD) is the most common subtype of NSCLC, characterized by poor prognosis and frequently diagnosed at advanced. While previous studies have demonstrated pleckstrin-2 (PLEK2) as aberrantly expressed and implicated in tumorigenesis across various tumor types, including LUAD, the molecular mechanisms underlying PLEK2-mediated LUAD progression remain incompletely understood. In this study, we obtained data from The Cancer Genome Atlas (TCGA) database to assess PLEK2 expression in LUAD, a finding further confirmed through analysis of human tissue specimens. PLEK2-silenced LUAD cellular models were subsequently constructed to examine the functional role of PLEK2 both in vitro and in vivo. Our results showed elevated PLEK2 expression in LUAD, correlating with poor patients' prognosis. PLEK2 knockdown led to a significant suppression of LUAD cell proliferation and migration, accompanied by enhanced apoptosis. Moreover, tumor growth in mice injected with PLEK2-silencing LUAD cells was impaired. Gene expression profiling and Co-IP assays suggested direct interaction between PLEK2 and SPC25, with downregulation of SPC25 similarly impairing cell proliferation and migration. Additionally, we revealed phosphoinositide 3-kinase (PI3K)/AKT signaling activation as requisite for PLEK2-induced malignant phenotypes in LUAD. Collectively, our findings underscore PLEK2's oncogenic potential in LUAD, suggesting its utility as a prognostic indicator and therapeutic target for LUAD management.
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Adenocarcinoma del Pulmón , Proliferación Celular , Neoplasias Pulmonares , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Humanos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Animales , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Adenocarcinoma del Pulmón/metabolismo , Adenocarcinoma del Pulmón/patología , Adenocarcinoma del Pulmón/genética , Línea Celular Tumoral , Ratones , Ratones Desnudos , Regulación hacia Arriba , Progresión de la Enfermedad , Regulación Neoplásica de la Expresión Génica , Movimiento Celular , Apoptosis/genética , Ratones Endogámicos BALB C , PronósticoRESUMEN
Molecules with high point-group symmetry are interesting prototype species in the textbook. As transition metal-centered boron clusters tend to have highly symmetric structures to fulfill multicenter bonding and high stability, new boron clusters with rare point-group symmetry may be viable. Through in-depth scrutiny over the structures of experimentally already observed transition metal-centered boron-wheel complexes, geometric and electronic design principles are summarized, based on which we studied M©B11k- (M = Y, La; Zr, Hf; k = 1, 2) clusters and found that a Y©B112- boron-wheel complex has an unprecedented D11h point-group symmetry. The remarkable stability of the planar Y©B112- complex is illustrated via extensive global-minimum structural search as well as comprehensive chemical bonding analyses. Similar to other boron-wheel complexes, the Y©B112- complex is shown to possess σ and π double aromaticity, indeed following the electronic design principle previously summarized. This new compound is expected to be experimentally identified, which will extend the currently known largest possible planar molecular symmetry and enrich the metal-centered boron-wheel class.
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Protein ubiquitination is a multifaceted post-translational modification that controls almost every process in eukaryotic cells. Recently, the Legionella effector SdeA was reported to mediate a unique phosphoribosyl-linked ubiquitination through successive modifications of the Arg42 of ubiquitin (Ub) by its mono-ADP-ribosyltransferase (mART) and phosphodiesterase (PDE) domains. However, the mechanisms of SdeA-mediated Ub modification and phosphoribosyl-linked ubiquitination remain unknown. Here we report the structures of SdeA in its ligand-free, Ub-bound and Ub-NADH-bound states. The structures reveal that the mART and PDE domains of SdeA form a catalytic domain over its C-terminal region. Upon Ub binding, the canonical ADP-ribosyltransferase toxin turn-turn (ARTT) and phosphate-nicotinamide (PN) loops in the mART domain of SdeA undergo marked conformational changes. The Ub Arg72 might act as a 'probe' that interacts with the mART domain first, and then movements may occur in the side chains of Arg72 and Arg42 during the ADP-ribosylation of Ub. Our study reveals the mechanism of SdeA-mediated Ub modification and provides a framework for further investigations into the phosphoribosyl-linked ubiquitination process.
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Legionella pneumophila/enzimología , Proteínas de la Membrana/química , Proteínas de la Membrana/metabolismo , Ubiquitina/metabolismo , Ubiquitinación , ADP Ribosa Transferasas/química , ADP Ribosa Transferasas/metabolismo , Arginina/metabolismo , Proteínas Bacterianas , Dominio Catalítico , Cristalografía por Rayos X , Modelos Moleculares , Chaperonas Moleculares/metabolismo , NAD/metabolismo , Hidrolasas Diéster Fosfóricas/química , Hidrolasas Diéster Fosfóricas/metabolismo , Procesamiento Proteico-Postraduccional , Especificidad por Sustrato , Ubiquitina/químicaRESUMEN
The impairment of blood-brain barrier (BBB) integrity is the pathological basis of hemorrhage transformation and vasogenic edema following thrombolysis and endovascular therapy. There is no approved drug in the clinic to reduce BBB damage after acute ischemic stroke (AIS). Glial growth factor 2 (GGF2), a recombinant version of neuregulin-1ß that can stimulates glial cell proliferation and differentiation, has been shown to alleviate free radical release from activated microglial cells. We previously found that activated microglia and proinflammatory factors could disrupt BBB after AIS. In this study we investigated the effects of GGF2 on AIS-induced BBB damage as well as the underlying mechanisms. Mouse middle cerebral artery occlusion model was established: mice received a 90-min ischemia and 22.5 h reperfusion (I/R), and were treated with GGF2 (2.5, 12.5, 50 ng/kg, i.v.) before the reperfusion. We showed that GGF2 treatment dose-dependently decreased I/R-induced BBB damage detected by Evans blue (EB) and immunoglobulin G (IgG) leakage, and tight junction protein occludin degradation. In addition, we found that GGF2 dose-dependently reversed AIS-induced upregulation of vesicular transcytosis increase, caveolin-1 (Cav-1) as well as downregulation of major facilitator superfamily domain containing 2a (Mfsd2a). Moreover, GGF2 decreased I/R-induced upregulation of PDZ and LIM domain protein 5 (Pdlim5), an adaptor protein that played an important role in BBB damage after AIS. In addition, GGF2 significantly alleviated I/R-induced reduction of YAP and TAZ, microglial cell activation and upregulation of inflammatory factors. Together, these results demonstrate that GGF2 treatment alleviates the I/R-compromised integrity of BBB by inhibiting Mfsd2a/Cav-1-mediated transcellular permeability and Pdlim5/YAP/TAZ-mediated paracellular permeability.
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PURPOSE: To retrospectively analyze the difference between triple-modal pre-rehabilitation and common treatment in patients with colorectal cancer (CRC). METHODS: A total of 145 patients with CRC diagnosed by pathology and admitted to our hospital for surgery between June 2020 and June 2022 were included in the study. All patients were divided into two groups: the triple-modal pre-rehabilitation group (pre-rehabilitation group) and the common treatment group. The triple-modal pre-rehabilitation strategy included exercise (3-5 times per week, with each session lasting more than 50 min), nutritional support, and psychological support. The study was designed to assess the potential of the pre-rehabilitation intervention to accelerate postoperative recovery by assessing the 6-min walk test, nutritional indicators, and HADS score before and after surgery. RESULTS: The pre-rehabilitation intervention did not reduce the duration of initial postoperative recovery or the incidence of postoperative complications, but it did increase the patients' exercise capacity (as determined by the 6-min walk test), with the pre-rehabilitation group performing significantly better than the common group (433.0 (105.0) vs. 389.0 (103.5), P < 0.001). The study also found that triple-modal pre-rehabilitation was beneficial for the early recovery of nutritional status in surgical patients and improved anxiety and depression in patients after surgery, especially in those who had not received neoadjuvant therapy. CONCLUSION: The triple-modal pre-rehabilitation strategy is of significant importance for reducing stress and improving the functional reserve of patients with colorectal cancer (CRC) during the perioperative period. The results of our study provide further support for the integration of the triple-modal pre-rehabilitation strategy into the treatment and care of CRC patients.