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1.
Mol Cell ; 83(1): 74-89.e9, 2023 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-36528027

RESUMEN

The GATOR2-GATOR1 signaling axis is essential for amino-acid-dependent mTORC1 activation. However, the molecular function of the GATOR2 complex remains unknown. Here, we report that disruption of the Ring domains of Mios, WDR24, or WDR59 completely impedes amino-acid-mediated mTORC1 activation. Mechanistically, via interacting with Ring domains of WDR59 and WDR24, the Ring domain of Mios acts as a hub to maintain GATOR2 integrity, disruption of which leads to self-ubiquitination of WDR24. Physiologically, leucine stimulation dissociates Sestrin2 from the Ring domain of WDR24 and confers its availability to UBE2D3 and subsequent ubiquitination of NPRL2, contributing to GATOR2-mediated GATOR1 inactivation. As such, WDR24 ablation or Ring deletion prevents mTORC1 activation, leading to severe growth defects and embryonic lethality at E10.5 in mice. Hence, our findings demonstrate that Ring domains are essential for GATOR2 to transmit amino acid availability to mTORC1 and further reveal the essentiality of nutrient sensing during embryonic development.


Asunto(s)
Complejos Multiproteicos , Serina-Treonina Quinasas TOR , Animales , Ratones , Diana Mecanicista del Complejo 1 de la Rapamicina/genética , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo , Complejos Multiproteicos/genética , Complejos Multiproteicos/metabolismo , Proteínas Nucleares/metabolismo , Transducción de Señal
2.
Nature ; 616(7955): 73-76, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37020005

RESUMEN

With strong reducibility and high redox potential, the hydride ion (H-) is a reactive hydrogen species and an energy carrier. Materials that conduct pure H- at ambient conditions will be enablers of advanced clean energy storage and electrochemical conversion technologies1,2. However, rare earth trihydrides, known for fast H migration, also exhibit detrimental electronic conductivity3-5. Here we show that by creating nanosized grains and defects in the lattice, the electronic conductivity of LaHx can be suppressed by more than five orders of magnitude. This transforms LaHx to a superionic conductor at -40 °C with a record high H- conductivity of 1.0 × 10-2 S cm-1 and a low diffusion barrier of 0.12 eV. A room-temperature all-solid-state hydride cell is demonstrated.

3.
Nature ; 618(7966): 799-807, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37316670

RESUMEN

Plants deploy receptor-like kinases and nucleotide-binding leucine-rich repeat receptors to confer host plant resistance (HPR) to herbivores1. These gene-for-gene interactions between insects and their hosts have been proposed for more than 50 years2. However, the molecular and cellular mechanisms that underlie HPR have been elusive, as the identity and sensing mechanisms of insect avirulence effectors have remained unknown. Here we identify an insect salivary protein perceived by a plant immune receptor. The BPH14-interacting salivary protein (BISP) from the brown planthopper (Nilaparvata lugens Stål) is secreted into rice (Oryza sativa) during feeding. In susceptible plants, BISP targets O. satvia RLCK185 (OsRLCK185; hereafter Os is used to denote O. satvia-related proteins or genes) to suppress basal defences. In resistant plants, the nucleotide-binding leucine-rich repeat receptor BPH14 directly binds BISP to activate HPR. Constitutive activation of Bph14-mediated immunity is detrimental to plant growth and productivity. The fine-tuning of Bph14-mediated HPR is achieved through direct binding of BISP and BPH14 to the selective autophagy cargo receptor OsNBR1, which delivers BISP to OsATG8 for degradation. Autophagy therefore controls BISP levels. In Bph14 plants, autophagy restores cellular homeostasis by downregulating HPR when feeding by brown planthoppers ceases. We identify an insect saliva protein sensed by a plant immune receptor and discover a three-way interaction system that offers opportunities for developing high-yield, insect-resistant crops.


Asunto(s)
Hemípteros , Proteínas de Insectos , Oryza , Defensa de la Planta contra la Herbivoria , Proteínas de Plantas , Animales , Hemípteros/inmunología , Hemípteros/fisiología , Leucina/metabolismo , Nucleótidos/metabolismo , Oryza/crecimiento & desarrollo , Oryza/inmunología , Oryza/metabolismo , Oryza/fisiología , Defensa de la Planta contra la Herbivoria/inmunología , Defensa de la Planta contra la Herbivoria/fisiología , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Proteínas de Insectos/metabolismo , Autofagia
4.
Mol Cell ; 81(11): 2317-2331.e6, 2021 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-33909988

RESUMEN

Aberrant energy status contributes to multiple metabolic diseases, including obesity, diabetes, and cancer, but the underlying mechanism remains elusive. Here, we report that ketogenic-diet-induced changes in energy status enhance the efficacy of anti-CTLA-4 immunotherapy by decreasing PD-L1 protein levels and increasing expression of type-I interferon (IFN) and antigen presentation genes. Mechanistically, energy deprivation activates AMP-activated protein kinase (AMPK), which in turn, phosphorylates PD-L1 on Ser283, thereby disrupting its interaction with CMTM4 and subsequently triggering PD-L1 degradation. In addition, AMPK phosphorylates EZH2, which disrupts PRC2 function, leading to enhanced IFNs and antigen presentation gene expression. Through these mechanisms, AMPK agonists or ketogenic diets enhance the efficacy of anti-CTLA-4 immunotherapy and improve the overall survival rate in syngeneic mouse tumor models. Our findings reveal a pivotal role for AMPK in regulating the immune response to immune-checkpoint blockade and advocate for combining ketogenic diets or AMPK agonists with anti-CTLA4 immunotherapy to combat cancer.


Asunto(s)
Proteínas Quinasas Activadas por AMP/genética , Antígeno B7-H1/genética , Neoplasias de la Mama/genética , Antígeno CTLA-4/genética , Neoplasias Colorrectales/genética , Inhibidores de Puntos de Control Inmunológico , Proteínas Quinasas Activadas por AMP/inmunología , Aloinjertos , Animales , Anticuerpos Neutralizantes/farmacología , Antineoplásicos/farmacología , Antígeno B7-H1/inmunología , Compuestos de Bifenilo/farmacología , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/terapia , Antígeno CTLA-4/antagonistas & inhibidores , Antígeno CTLA-4/inmunología , Línea Celular Tumoral , Neoplasias Colorrectales/inmunología , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/terapia , Dieta Cetogénica/métodos , Metabolismo Energético/efectos de los fármacos , Metabolismo Energético/genética , Proteína Potenciadora del Homólogo Zeste 2/genética , Proteína Potenciadora del Homólogo Zeste 2/inmunología , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunoterapia/métodos , Proteínas con Dominio MARVEL/genética , Proteínas con Dominio MARVEL/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Desnudos , Pironas/farmacología , Transducción de Señal , Análisis de Supervivencia , Tiofenos/farmacología
5.
Nat Chem Biol ; 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39103634

RESUMEN

Liver fibrosis is an urgent clinical problem without effective therapies. Here we conducted a high-content screening on a natural Euphorbiaceae diterpenoid library to identify a potent anti-liver fibrosis lead, 12-deoxyphorbol 13-palmitate (DP). Leveraging a photo-affinity labeling approach, apolipoprotein L2 (APOL2), an endoplasmic reticulum (ER)-rich protein, was identified as the direct target of DP. Mechanistically, APOL2 is induced in activated hepatic stellate cells upon transforming growth factor-ß1 (TGF-ß1) stimulation, which then binds to sarcoplasmic/ER calcium ATPase 2 (SERCA2) to trigger ER stress and elevate its downstream protein kinase R-like ER kinase (PERK)-hairy and enhancer of split 1 (HES1) axis, ultimately promoting liver fibrosis. As a result, targeting APOL2 by DP or ablation of APOL2 significantly impairs APOL2-SERCA2-PERK-HES1 signaling and mitigates fibrosis progression. Our findings not only define APOL2 as a novel therapeutic target for liver fibrosis but also highlight DP as a promising lead for treatment of this symptom.

6.
Nature ; 571(7766): E10, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31270456

RESUMEN

An Amendment to this paper has been published and can be accessed via a link at the top of the paper. The original Letter has not been corrected.

7.
Proc Natl Acad Sci U S A ; 119(10): e2110756119, 2022 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-35235447

RESUMEN

SignificanceAerosol-cloud interaction affects the cooling of Earth's climate, mostly by activation of aerosols as cloud condensation nuclei that can increase the amount of sunlight reflected back to space. But the controlling physical processes remain uncertain in current climate models. We present a lidar-based technique as a unique remote-sensing tool without thermodynamic assumptions for simultaneously profiling diurnal aerosol and water cloud properties with high resolution. Direct lateral observations of cloud properties show that the vertical structure of low-level water clouds can be far from being perfectly adiabatic. Furthermore, our analysis reveals that, instead of an increase of liquid water path (LWP) as proposed by most general circulation models, elevated aerosol loading can cause a net decrease in LWP.

8.
Gut ; 73(7): 1156-1168, 2024 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-38191266

RESUMEN

OBJECTIVE: Whether and how the PI3K-AKT pathway, a central node of metabolic homeostasis, is responsible for high-fat-induced non-alcoholic steatohepatitis (NASH) and hepatocellular carcinoma (HCC) remain a mystery. Characterisation of AKT regulation in this setting will provide new strategies to combat HCC. DESIGN: Metabolite library screening disclosed that palmitic acid (PA) could activate AKT. In vivo and in vitro palmitoylation assay were employed to detect AKT palmitoylation. Diverse cell and mouse models, including generation of AKT1C77S and AKT1C224S knock-in cells, Zdhhc17 and Zdhhc24 knockout mice and Akt1C224S knock-in mice were employed. Human liver tissues from patients with NASH and HCC, hydrodynamic transfection mouse model, high-fat/high-cholesterol diet (HFHCD)-induced NASH/HCC mouse model and high-fat and methionine/choline-deficient diet (HFMCD)-induced NASH mouse model were also further explored for our mechanism studies. RESULTS: By screening a metabolite library, PA has been defined to activate AKT by promoting its palmitoyl modification, an essential step for growth factor-induced AKT activation. Biologically, a high-fat diet could promote AKT kinase activity, thereby promoting NASH and liver cancer. Mechanistically, palmitoyl binding anchors AKT to the cell membrane in a PIP3-independent manner, in part by preventing AKT from assembling into an inactive polymer. The palmitoyltransferases ZDHHC17/24 were characterised to palmitoylate AKT to exert oncogenic effects. Interestingly, the anti-obesity drug orlistat or specific penetrating peptides can effectively attenuate AKT palmitoylation and activation by restricting PA synthesis or repressing AKT modification, respectively, thereby antagonising liver tumorigenesis. CONCLUSIONS: Our findings elucidate a novel fine-tuned regulation of AKT by PA-ZDHHC17/24-mediated palmitoylation, and highlight tumour therapeutic strategies by taking PA-restricted diets, limiting PA synthesis, or directly targeting AKT palmitoylation.


Asunto(s)
Carcinoma Hepatocelular , Dieta Alta en Grasa , Lipoilación , Neoplasias Hepáticas , Enfermedad del Hígado Graso no Alcohólico , Proteínas Proto-Oncogénicas c-akt , Animales , Proteínas Proto-Oncogénicas c-akt/metabolismo , Dieta Alta en Grasa/efectos adversos , Ratones , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/etiología , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/etiología , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/patología , Humanos , Ácido Palmítico/metabolismo , Carcinogénesis/metabolismo , Ratones Noqueados , Modelos Animales de Enfermedad , Masculino , Transducción de Señal
9.
J Hepatol ; 81(2): 265-277, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38508240

RESUMEN

BACKGROUND & AIMS: Intrahepatic cholangiocarcinoma (iCCA) is the second most common primary liver cancer and is highly lethal. Clonorchis sinensis (C. sinensis) infection is an important risk factor for iCCA. Here we investigated the clinical impact and underlying molecular characteristics of C. sinensis infection-related iCCA. METHODS: We performed single-cell RNA sequencing, whole-exome sequencing, RNA sequencing, metabolomics and spatial transcriptomics in 251 patients with iCCA from three medical centers. Alterations in metabolism and the immune microenvironment of C. sinensis-related iCCAs were validated through an in vitro co-culture system and in a mouse model of iCCA. RESULTS: We revealed that C. sinensis infection was significantly associated with iCCA patients' overall survival and response to immunotherapy. Fatty acid biosynthesis and the expression of fatty acid synthase (FASN), a key enzyme catalyzing long-chain fatty acid synthesis, were significantly enriched in C. sinensis-related iCCAs. iCCA cell lines treated with excretory/secretory products of C. sinensis displayed elevated FASN and free fatty acids. The metabolic alteration of tumor cells was closely correlated with the enrichment of tumor-associated macrophage (TAM)-like macrophages and the impaired function of T cells, which led to formation of an immunosuppressive microenvironment and tumor progression. Spatial transcriptomics analysis revealed that malignant cells were in closer juxtaposition with TAM-like macrophages in C. sinensis-related iCCAs than non-C. sinensis-related iCCAs. Importantly, treatment with a FASN inhibitor significantly reversed the immunosuppressive microenvironment and enhanced anti-PD-1 efficacy in iCCA mouse models treated with excretory/secretory products from C. sinensis. CONCLUSIONS: We provide novel insights into metabolic alterations and the immune microenvironment in C. sinensis infection-related iCCAs. We also demonstrate that the combination of a FASN inhibitor with immunotherapy could be a promising strategy for the treatment of C. sinensis-related iCCAs. IMPACT AND IMPLICATIONS: Clonorchis sinensis (C. sinensis)-infected patients with intrahepatic cholangiocarcinoma (iCCA) have a worse prognosis and response to immunotherapy than non-C. sinensis-infected patients with iCCA. The underlying molecular characteristics of C. sinensis infection-related iCCAs remain unclear. Herein, we demonstrate that upregulation of FASN (fatty acid synthase) and free fatty acids in C. sinensis-related iCCAs leads to formation of an immunosuppressive microenvironment and tumor progression. Thus, administration of FASN inhibitors could significantly reverse the immunosuppressive microenvironment and further enhance the efficacy of anti-PD-1 against C. sinensis-related iCCAs.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Clonorquiasis , Clonorchis sinensis , Ácidos Grasos , Microambiente Tumoral , Colangiocarcinoma/inmunología , Colangiocarcinoma/parasitología , Animales , Clonorchis sinensis/inmunología , Clonorchis sinensis/fisiología , Clonorquiasis/inmunología , Neoplasias de los Conductos Biliares/inmunología , Neoplasias de los Conductos Biliares/parasitología , Ratones , Microambiente Tumoral/inmunología , Humanos , Ácidos Grasos/metabolismo , Acido Graso Sintasa Tipo I/genética , Acido Graso Sintasa Tipo I/antagonistas & inhibidores , Acido Graso Sintasa Tipo I/metabolismo , Masculino , Femenino , Línea Celular Tumoral , Modelos Animales de Enfermedad , Macrófagos Asociados a Tumores/inmunología , Macrófagos Asociados a Tumores/metabolismo
10.
Ann Rheum Dis ; 83(5): 576-588, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38302261

RESUMEN

OBJECTIVES: B10 and B10pro cells suppress immune responses via secreting interleukin (IL)-10. However, their regulators and underlying mechanisms, especially in human autoimmune diseases, are elusive. This study aimed to address these questions in rheumatoid arthritis (RA), one of the most common highly disabling autoimmune diseases. METHODS: The frequencies and functions of B10 and B10pro cells in healthy individuals and patients with RA were first analysed. The effects of proinflammatory cytokines, particularly tumour necrosis factor (TNF)-α on the quantity, stability and pathogenic phenotype of these cells, were then assessed in patients with RA before and after anti-TNF therapy. The underlying mechanisms were further investigated by scRNA-seq database reanalysis, transcriptome sequencing, TNF-α-/- and B cell-specific SHIP-1-/- mouse disease model studies. RESULTS: TNF-α was a key determinant for B10 cells. TNF-α elicited the proinflammatory feature of B10 and B10pro cells by downregulating IL-10, and upregulating interferon-γ and IL-17A. In patients with RA, B10 and B10pro cells were impaired with exacerbated proinflammatory phenotype, while anti-TNF therapy potently restored their frequencies and immunosuppressive functions, consistent with the increased B10 cells in TNF-α-/- mice. Mechanistically, TNF-α diminished B10 and B10pro cells by inhibiting their glycolysis and proliferation. TNF-α also regulated the phosphatidylinositol phosphate signalling of B10 and B10pro cells and dampened the expression of SHIP-1, a dominant phosphatidylinositol phosphatase regulator of these cells. CONCLUSIONS: TNF-α provoked the proinflammatory phenotype of B10 and B10pro cells by disturbing SHIP-1 in RA, contributing to the disease development. Reinstating the immunosuppressive property of B10 and B10pro cells might represent novel therapeutic approaches for RA.


Asunto(s)
Artritis Reumatoide , Enfermedades Autoinmunes , Linfocitos B Reguladores , Factor de Necrosis Tumoral alfa , Animales , Humanos , Ratones , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/metabolismo , Enfermedades Autoinmunes/metabolismo , Linfocitos B Reguladores/metabolismo , Fenotipo , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatasas/genética , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatasas/metabolismo , Inhibidores del Factor de Necrosis Tumoral/uso terapéutico , Factor de Necrosis Tumoral alfa/metabolismo
11.
Rheumatology (Oxford) ; 63(3): 846-855, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37462532

RESUMEN

OBJECTIVE: Leukocyte Ig-like receptor A3 (LILRA3) is a soluble receptor belongs to the immunoglobulin superfamily. Our previous studies demonstrated that LILRA3 is a common genetic risk for multiple autoimmune diseases, including RA. Functional LILRA3 conferred increased risk of joint destruction in patients with early RA. We undertook this study to further investigate the pathological role of LILRA3 in joint inflammation of RA. METHODS: Soluble LILRA3 was measured by ELISA. LILRA3 plasmids were transfected into human fibroblast-like synoviocytes (FLSs) using electroporation. Activation of extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) was determined by western blots. Cytokine transcripts were quantified by real-time PCR. Migratory and invasive capacities of FLSs were evaluated using transwell migration and Matrigel invasion assays. FLS apoptosis was analysed using flow cytometry. Colocalization of LILRA3, LILRB1 and HLA-G in RA-FLSs was visualized by immunofluorescence staining. RESULTS: Soluble LILRA3 was specifically expressed in synovial fluid and serum LILRA3 was significantly increased and positively correlated with disease activity/severity in RA patients. LILRA3 induced an increased expression of IL-6, IL-8 and MMP3 in RA-FLSs. In vitro LILRA3 stimulation or overexpression promoted RA-FLS migration and invasion, and enhanced phosphorylation of ERK/JNK. Inhibition of ERK/JNK resulted in suppression of IL-6/IL-8 expression in LILRA3-stimulated RA-FLSs. LILRA3 was co-localized with its homologue LILRB1 and shared ligand HLA-G in RA-FLSs. CONCLUSION: The present study provides the first evidence that soluble LILRA3 is a novel proinflammatory mediator involved in synovial inflammation by promoting RA-FLS activation, migration and invasion, probably through the ERK/JNK signalling pathways.


Asunto(s)
Quinasas MAP Reguladas por Señal Extracelular , Antígenos HLA-G , Humanos , Receptor Leucocitario Tipo Inmunoglobulina B1 , Interleucina-6 , Interleucina-8 , Inflamación , Receptores Inmunológicos
12.
J Card Fail ; 30(6): 853-856, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38513886

RESUMEN

BACKGROUND: It is common for clinicians to use the pulmonary artery diastolic pressure (PADP) as a surrogate for the pulmonary capillary wedge pressure (PCWP). Here, we determine the validity of this relationship in patients with various phenotypes of cardiogenic shock (CS). METHODS AND RESULTS: In this analysis of the Critical Care Cardiology Trials Network registry, we identified 1225 people admitted with CS who received pulmonary artery catheters. Linear regression, Bland-Altman and receiver operator characteristic analyses were performed to determine the strength of the association between PADP and PCWP in patients with left-, right-, biventricular, and other non-myocardia phenotypes of CS (eg, arrhythmia, valvular stenosis, tamponade). There was a moderately strong correlation between PADP and PCWP in the total population (r = 0.64, n = 1225) and in each CS phenotype, except for right ventricular CS, for which the correlation was weak (r = 0.43, n = 71). Additionally, we found that a PADP ≥ 24 mmHg can be used to infer a PCWP ≥ 18 mmHg with ≥ 90% confidence in all but the right ventricular CS phenotype. CONCLUSIONS: This analysis validates the practice of using PADP as a surrogate for PCWP in most patients with CS; however, it should generally be avoided in cases of right ventricular-predominant CS.


Asunto(s)
Arteria Pulmonar , Presión Esfenoidal Pulmonar , Sistema de Registros , Choque Cardiogénico , Humanos , Presión Esfenoidal Pulmonar/fisiología , Masculino , Femenino , Choque Cardiogénico/fisiopatología , Persona de Mediana Edad , Anciano , Arteria Pulmonar/fisiopatología , Diástole
13.
Mol Biol Rep ; 51(1): 506, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38622341

RESUMEN

BACKGROUND: Atrial Fibrillation (AF), a prevalent arrhythmic condition, is intricately associated with atrial fibrosis, a major pathological contributor. Central to the development of atrial fibrosis is myocardial inflammation. This study focuses on Atrial Natriuretic Peptide (ANP) and its role in mitigating atrial fibrosis, aiming to elucidate the specific mechanisms by which ANP exerts its effects, with an emphasis on fibroblast dynamics. METHODS AND RESULTS: The study involved forty Sprague-Dawley rats, divided into four groups: control, Angiotensin II (Ang II), Ang II + ANP, and ANP only. The administration of 1 µg/kg/min Ang II was given to Ang II and Ang II + ANP groups, while both Ang II + ANP and ANP groups received 0.1 µg/kg/min ANP intravenously for a duration of 14 days. Cardiac fibroblasts were used for in vitro validation of the proposed mechanisms. The study observed that rats in the Ang II and Ang II + ANP groups showed an increase in blood pressure and a decrease in body weight, more pronounced in the Ang II group. Diastolic dysfunction, a characteristic of the Ang II group, was alleviated by ANP. Additionally, ANP significantly reduced Ang II-induced atrial fibrosis, myofibroblast proliferation, collagen overexpression, macrophage infiltration, and the elevated expression of Interleukin 6 (IL-6) and Tenascin-C (TN-C). Transcriptomic sequencing indicated enhanced PI3K/Akt signaling in the Ang II group. Furthermore, in vitro studies showed that ANP, along with the PI3K inhibitor LY294002, effectively reduced PI3K/Akt pathway activation and the expression of TN-C, collagen-I, and collagen-III, which were induced by Ang II. CONCLUSIONS: The study demonstrates ANP's potential in inhibiting myocardial inflammation and reducing atrial fibrosis. Notably, ANP's effect in countering atrial fibrosis seems to be mediated through the suppression of the Ang II-induced PI3K/Akt-Tenascin-C signaling pathway. These insights enhance our understanding of AF pathogenesis and position ANP as a potential therapeutic agent for treating atrial fibrosis.


Asunto(s)
Fibrilación Atrial , Factor Natriurético Atrial , Ratas , Animales , Ratas Sprague-Dawley , Factor Natriurético Atrial/farmacología , Factor Natriurético Atrial/metabolismo , Proteínas Proto-Oncogénicas c-akt , Fosfatidilinositol 3-Quinasas , Tenascina , Fibrilación Atrial/tratamiento farmacológico , Angiotensina II/farmacología , Inflamación/tratamiento farmacológico , Colágeno , Fibrosis
14.
Nature ; 553(7686): 91-95, 2018 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-29160310

RESUMEN

Treatments that target immune checkpoints, such as the one mediated by programmed cell death protein 1 (PD-1) and its ligand PD-L1, have been approved for treating human cancers with durable clinical benefit. However, many patients with cancer fail to respond to compounds that target the PD-1 and PD-L1 interaction, and the underlying mechanism(s) is not well understood. Recent studies revealed that response to PD-1-PD-L1 blockade might correlate with PD-L1 expression levels in tumour cells. Hence, it is important to understand the mechanistic pathways that control PD-L1 protein expression and stability, which can offer a molecular basis to improve the clinical response rate and efficacy of PD-1-PD-L1 blockade in patients with cancer. Here we show that PD-L1 protein abundance is regulated by cyclin D-CDK4 and the cullin 3-SPOP E3 ligase via proteasome-mediated degradation. Inhibition of CDK4 and CDK6 (hereafter CDK4/6) in vivo increases PD-L1 protein levels by impeding cyclin D-CDK4-mediated phosphorylation of speckle-type POZ protein (SPOP) and thereby promoting SPOP degradation by the anaphase-promoting complex activator FZR1. Loss-of-function mutations in SPOP compromise ubiquitination-mediated PD-L1 degradation, leading to increased PD-L1 levels and reduced numbers of tumour-infiltrating lymphocytes in mouse tumours and in primary human prostate cancer specimens. Notably, combining CDK4/6 inhibitor treatment with anti-PD-1 immunotherapy enhances tumour regression and markedly improves overall survival rates in mouse tumour models. Our study uncovers a novel molecular mechanism for regulating PD-L1 protein stability by a cell cycle kinase and reveals the potential for using combination treatment with CDK4/6 inhibitors and PD-1-PD-L1 immune checkpoint blockade to enhance therapeutic efficacy for human cancers.


Asunto(s)
Antígeno B7-H1/metabolismo , Proteínas Cullin/metabolismo , Ciclina D/metabolismo , Quinasa 4 Dependiente de la Ciclina/metabolismo , Vigilancia Inmunológica , Neoplasias/inmunología , Proteínas Nucleares/metabolismo , Proteínas Represoras/metabolismo , Escape del Tumor/inmunología , Proteínas 14-3-3/metabolismo , Animales , Antígeno B7-H1/biosíntesis , Proteínas Cdh1/metabolismo , Ciclo Celular , Línea Celular , Quinasa 4 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 6 Dependiente de la Ciclina/antagonistas & inhibidores , Femenino , Humanos , Linfocitos Infiltrantes de Tumor/citología , Linfocitos Infiltrantes de Tumor/inmunología , Masculino , Ratones , Proteínas Nucleares/química , Fosforilación , Receptor de Muerte Celular Programada 1/metabolismo , Neoplasias de la Próstata/inmunología , Complejo de la Endopetidasa Proteasomal/metabolismo , Estabilidad Proteica , Proteolisis , Proteínas Represoras/química
15.
Mol Cell ; 62(6): 929-942, 2016 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-27237051

RESUMEN

The retinoblastoma (Rb) protein exerts its tumor suppressor function primarily by inhibiting the E2F family of transcription factors that govern cell-cycle progression. However, it remains largely elusive whether the hyper-phosphorylated, non-E2F1-interacting form of Rb has any physiological role. Here we report that hyper-phosphorylated Rb directly binds to and suppresses the function of mTORC2 but not mTORC1. Mechanistically, Rb, but not p107 or p130, interacts with Sin1 and blocks the access of Akt to mTORC2, leading to attenuated Akt activation and increased sensitivity to chemotherapeutic drugs. As such, inhibition of Rb phosphorylation by depleting cyclin D or using CDK4/6 inhibitors releases Rb-mediated mTORC2 suppression. This, in turn, leads to elevated Akt activation to confer resistance to chemotherapeutic drugs in Rb-proficient cells, which can be attenuated with Akt inhibitors. Therefore, our work provides a molecular basis for the synergistic usage of CDK4/6 and Akt inhibitors in treating Rb-proficient cancer.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Complejos Multiproteicos/metabolismo , Neoplasias/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Proteína de Retinoblastoma/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Proliferación Celular/efectos de los fármacos , Ciclina D/genética , Ciclina D/metabolismo , Quinasa 4 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 4 Dependiente de la Ciclina/metabolismo , Quinasa 6 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 6 Dependiente de la Ciclina/metabolismo , Relación Dosis-Respuesta a Droga , Resistencia a Antineoplásicos , Sinergismo Farmacológico , Activación Enzimática , Células HCT116 , Células HEK293 , Células HeLa , Humanos , Diana Mecanicista del Complejo 2 de la Rapamicina , Ratones , Terapia Molecular Dirigida , Neoplasias/enzimología , Neoplasias/genética , Neoplasias/patología , Fosforilación , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Proteínas Proto-Oncogénicas c-akt/metabolismo , Interferencia de ARN , Transducción de Señal , Factores de Tiempo , Transfección
16.
Proc Natl Acad Sci U S A ; 118(8)2021 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-33593919

RESUMEN

Secondary organic aerosol (SOA) produced by atmospheric oxidation of primary emitted precursors is a major contributor to fine particulate matter (PM2.5) air pollution worldwide. Observations during winter haze pollution episodes in urban China show that most of this SOA originates from fossil-fuel combustion but the chemical mechanisms involved are unclear. Here we report field observations in a Beijing winter haze event that reveal fast aqueous-phase conversion of fossil-fuel primary organic aerosol (POA) to SOA at high relative humidity. Analyses of aerosol mass spectra and elemental ratios indicate that ring-breaking oxidation of POA aromatic species, leading to functionalization as carbonyls and carboxylic acids, may serve as the dominant mechanism for this SOA formation. A POA origin for SOA could explain why SOA has been decreasing over the 2013-2018 period in response to POA emission controls even as emissions of volatile organic compounds (VOCs) have remained flat.

17.
Eur Heart J ; 44(4): 293-300, 2023 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-36303404

RESUMEN

AIMS: Levels of growth differentiation factor 15 (GDF-15), a cytokine secreted in response to cellular stress and inflammation, have been associated with multiple types of cardiovascular (CV) events. However, its comparative prognostic performance across different presentations of atherosclerotic cardiovascular disease (ASCVD) remains unknown. METHODS AND RESULTS: An individual patient meta-analysis was performed using data pooled from eight trials including 53 486 patients. Baseline GDF-15 concentration was analyzed as a continuous variable and using established cutpoints (<1200 ng/L, 1200-1800 ng/L, > 1800 ng/L) to evaluate its prognostic performance for CV death/hospitalization for heart failure (HHF), major adverse cardiovascular events (MACE), and their components using Cox models adjusted for clinical variables and established CV biomarkers. Analyses were further stratified on ASCVD status: acute coronary syndrome (ACS), stabilized after recent ACS, and stable ASCVD. Overall, higher GDF-15 concentration was significantly and independently associated with an increased rate of CV death/HHF and MACE (P < 0.001 for each). However, while GDF-15 showed a robust and consistent independent association with CV death and HHF across all presentations of ASCVD, its prognostic association with future myocardial infarction (MI) and stroke only remained significant in patients stabilized after recent ACS or with stable ASCVD [hazard ratio (HR): 1.24, 95% confidence interval (CI): 1.17-1.31 and HR: 1.16, 95% CI: 1.05-1.28 for MI and stroke, respectively] and not in ACS (HR: 0.98, 95% CI: 0.90-1.06 and HR: 0.87, 95% CI: 0.39-1.92, respectively). CONCLUSION: Growth differentiation factor 15 consistently adds prognostic information for CV death and HHF across the spectrum of ASCVD. GDF-15 also adds prognostic information for MI and stroke beyond clinical risk factors and cardiac biomarkers but not in the setting of ACS.


Asunto(s)
Síndrome Coronario Agudo , Aterosclerosis , Enfermedades Cardiovasculares , Insuficiencia Cardíaca , Infarto del Miocardio , Accidente Cerebrovascular , Humanos , Enfermedades Cardiovasculares/complicaciones , Factor 15 de Diferenciación de Crecimiento , Factores de Riesgo , Infarto del Miocardio/etiología , Síndrome Coronario Agudo/complicaciones , Biomarcadores , Insuficiencia Cardíaca/complicaciones , Accidente Cerebrovascular/complicaciones , Factores de Riesgo de Enfermedad Cardiaca , Aterosclerosis/complicaciones
18.
Sensors (Basel) ; 24(6)2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38544011

RESUMEN

When mining deep coal seams with thin bedrock and thick alluvium, the collapse and fracture of thin bedrock layers may cause geological disasters, such as water inrush and sand inrush of the mining face. Comprehensively obtaining the response data of coal mining and reasonably analyzing the failure characteristics of overlying strata are helpful in guiding safe production. In this study, the caving zone heights of overlying strata are obtained by field detection during layered mining. Then, the caving zone heights during the once-full-height mining are evaluated by theoretical analysis. Further, the force and failure characteristics of coal-rock structures under different mining conditions are compared by the simulation detection and analysis. Finally, the results of on-site observation, theoretical analysis, and simulation detection are compared and discussed, and an optimized mining technology is proposed to ensure safe mining. The research shows the caving zone heights of on-site and simulation detections are, respectively, 14.65 m and 13.5 m during bottom-layer mining, which is larger than the caving zone heights of the top-layer coal mining. During once-full-height mining, the maximum caving zone height of simulation detection is 21 m, which is in between two standard results. For the mechanical responses of an aquiclude clay layer under thick loose alluvium, the maximum disturbance displacement of clay aquiclude is 5.8 m during layered mining, which is slightly larger than the disturbance displacement of once full-height mining; however, the maximum stress of the clay layer is 25 MPa during once-full-height mining, which is larger than the maximum stress of clay layer during layered mining. For the clay aquiclude failure, the clay layer during layered mining is in the deflection deformation area, and there is no obvious fracture structure to inrush the water and sand of thick loose alluvium; however, the clay layer during once-full-height mining is prone to produce obvious fracture structure. Therefore, the layered mining technology can effectively reduce and prevent the water/sand inrush disaster of mining working face.

19.
Br J Cancer ; 128(8): 1452-1465, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36807336

RESUMEN

BACKGROUND: Predominant roles of copper and its transporter, copper transporter 1 (CTR1), in tumorigenesis have been explored recently; however, the upstream regulation of CTR1 and combinational intervention of copper chelators in malignancies remain largely unclear. METHODS: CRISPR/Cas9-based kinome screening was used to identify the CTR1 upstream kinases. Immunofluorescence assays were utilised to detect CTR1 localisation. In vitro kinase assays and mass spectrometry were performed to detect CTR1 phosphorylation. Ubiquitination assays were performed to validate CTR1 stability. Colony formation, EdU labelling, Annexin V-FITC/PI-based apoptosis assays were carried out to detect the drug effect on cell growth and apoptosis. Xenografted mouse models were employed to investigate drug effects in vivo. RESULTS: We identify that CTR1 undergoes AMPK-mediated phosphorylation, which enhances CTR1 stabilisation and membrane translocation by affecting Nedd4l interaction, resulting in increased oncogenic roles in breast cancer. Importantly, activation of AMPK with its agonist metformin markedly enhances CTR1 levels, and leads to the combinational usage of AMPK agonists and copper chelators for breast cancer treatment. CONCLUSIONS: Our findings not only reveal the crosstalk between energy response and copper uptake via AMPK-mediated CTR1 phosphorylation and stability but also highlight the strategy to combat breast cancer by a combination of AMPK agonists and copper chelators. SIGNIFICANCE: The connection between energy response and copper homoeostasis is linked by AMPK phosphorylating and stabilising CTR1, which provides a promising strategy to combat breast cancer by combining AMPK agonists and copper chelators.


Asunto(s)
Proteínas de Transporte de Catión , Metformina , Neoplasias , Animales , Ratones , Transportador de Cobre 1 , Proteínas Quinasas Activadas por AMP/metabolismo , Cobre/metabolismo , Cobre/farmacología , Metformina/farmacología , Proteínas de Transporte de Catión/química , Proteínas de Transporte de Catión/metabolismo , Quelantes/farmacología
20.
Opt Lett ; 48(22): 6004-6007, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37966774

RESUMEN

It is a highly significant area of research to investigate how to effectively enhance the focusing ability of abruptly auto-focusing beams (AAFBs) while extending the focal length. We introduce a dual-region parabolic trajectory offset modulation to auto-focusing ring Pearcey beams (RPBs), presenting a novel, to the best of our knowlege, approach to extend the focal length while greatly enhancing their auto-focusing capabilities. Unlike directly introducing a linear chirp, which inevitably shortens the focal length to enhance the auto-focusing ability and allows only single focusing in the RPBs, our scheme can achieve a multi-focusing effect. Furthermore, we have experimentally generated such a beam, verifying our theoretical predictions. Our findings offer promising possibilities for generating optical bottles, trapping multiple particles periodically, and enhancing free-space optical communication capabilities.

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