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1.
Nature ; 621(7980): 711-715, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37758892

RESUMEN

The nearby radio galaxy M87 offers a unique opportunity to explore the connections between the central supermassive black hole and relativistic jets. Previous studies of the inner region of M87 revealed a wide opening angle for the jet originating near the black hole1-4. The Event Horizon Telescope resolved the central radio source and found an asymmetric ring structure consistent with expectations from general relativity5. With a baseline of 17 years of observations, there was a shift in the jet's transverse position, possibly arising from an 8- to 10-year quasi-periodicity3. However, the origin of this sideways shift remains unclear. Here we report an analysis of radio observations over 22 years that suggests a period of about 11 years for the variation in the position angle of the jet. We infer that we are seeing a spinning black hole that induces the Lense-Thirring precession of a misaligned accretion disk. Similar jet precession may commonly occur in other active galactic nuclei but has been challenging to detect owing to the small magnitude and long period of the variation.

2.
Development ; 147(21)2020 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-32376680

RESUMEN

Sonic hedgehog (Shh) signaling is essential for proliferation of cerebellar granule neuron progenitors (CGNPs) and its mis-regulation is linked to various disorders, including the cerebellar cancer medulloblastoma (MB). We recently identified RNF220, a ubiquitin E3 ligase promoting K63-linked polyubiquitylation and nuclear exportation of Gli transcription factors, as an Shh/Gli regulator involved in ventral neural patterning. Here, we report that RNF220 is required for the proliferation of CGNPs and Daoy cells (an Shh-grouped MB cell line), working as a positive regulator of Shh signaling. Mechanistic investigation demonstrated that RNF220 promotes Shh target gene expression by targeting the PRC2 component EED, and alters levels of epigenetic modification marks on Shh target promoters. We provided evidence that RNF220+/-; Ptch1+/- mice showed lower spontaneous MB occurrence compared with Ptch1+/- mice. Furthermore, in human clinical MB samples, RNF220 expression correlated well with that of GAB1, an Shh-group MB marker. Our findings provide new insights into the epigenetic regulation of Shh signaling and identify RNF220 as a potential new diagnostic marker and therapeutic target for Shh-group MB.


Asunto(s)
Cerebelo/embriología , Progresión de la Enfermedad , Epigénesis Genética , Proteínas Hedgehog/genética , Meduloblastoma/genética , Meduloblastoma/patología , Transducción de Señal , Ubiquitina-Proteína Ligasas/metabolismo , Animales , Línea Celular Tumoral , Proliferación Celular , Cerebelo/patología , Gránulos Citoplasmáticos/metabolismo , Regulación Neoplásica de la Expresión Génica , Proteínas Hedgehog/metabolismo , Humanos , Lisina/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Células-Madre Neurales/metabolismo , Complejo Represivo Polycomb 2/metabolismo , Poliubiquitina/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Unión Proteica , Proteolisis , Ubiquitina-Proteína Ligasas/genética , Ubiquitinación , Ensayos Antitumor por Modelo de Xenoinjerto
3.
Acta Pharmacol Sin ; 44(2): 421-433, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35953646

RESUMEN

The paradigm of one drug against multiple targets, known as unimolecular polypharmacology, offers the potential to improve efficacy while overcoming some adverse events associated with the treatment. This approach is best exemplified by targeting two or three class B1 G protein-coupled receptors, namely, glucagon-like peptide-1 receptor (GLP-1R), glucagon receptor (GCGR) and glucose-dependent insulinotropic polypeptide receptor for treatment of type 2 diabetes and obesity. Some of the dual and triple agonists have already shown initial successes in clinical trials, although the molecular mechanisms underlying their multiplexed pharmacology remain elusive. In this study we employed structure-based site-directed mutagenesis together with pharmacological assays to compare agonist efficacy across two key signaling pathways, cAMP accumulation and ERK1/2 phosphorylation (pERK1/2). Three dual agonists (peptide 15, MEDI0382 and SAR425899) and one triple agonist (peptide 20) were evaluated at GLP-1R and GCGR, relative to the native peptidic ligands (GLP-1 and glucagon). Our results reveal the existence of residue networks crucial for unimolecular agonist-mediated receptor activation and their distinct signaling patterns, which might be useful to the rational design of biased drug leads.


Asunto(s)
Diabetes Mellitus Tipo 2 , Péptido 1 Similar al Glucagón , Humanos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Péptido 1 Similar al Glucagón/genética , Péptido 1 Similar al Glucagón/agonistas , Receptor del Péptido 1 Similar al Glucagón/genética , Receptor del Péptido 1 Similar al Glucagón/metabolismo , Mutagénesis Sitio-Dirigida , Péptidos/química , Receptores de Glucagón/genética , Receptores de Glucagón/agonistas , Receptores de Glucagón/metabolismo , Transducción de Señal , Factores de Transcripción
4.
Acta Pharmacol Sin ; 44(6): 1227-1237, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36482086

RESUMEN

Parathyroid hormone (PTH) and PTH-related peptide (PTHrP) are two endogenous hormones recognized by PTH receptor-1 (PTH1R), a member of class B G protein- coupled receptors (GPCRs). Both PTH and PTHrP analogs including teriparatide and abaloparatide are approved drugs for osteoporosis, but they exhibit distinct pharmacology. Here we report two cryo-EM structures of human PTH1R bound to PTH and PTHrP in the G protein-bound state at resolutions of 2.62 Å and 3.25 Å, respectively. Detailed analysis of these structures uncovers both common and unique features for the agonism of PTH and PTHrP. Molecular dynamics (MD) simulation together with site-directed mutagenesis studies reveal the molecular basis of endogenous hormones recognition specificity and selectivity to PTH1R. These results provide a rational template for the clinical use of PTH and PTHrP analogs as an anabolic therapy for osteoporosis and other disorders.


Asunto(s)
Osteoporosis , Proteína Relacionada con la Hormona Paratiroidea , Humanos , Proteína Relacionada con la Hormona Paratiroidea/metabolismo , Proteína Relacionada con la Hormona Paratiroidea/farmacología , Secuencia de Aminoácidos , Hormona Paratiroidea/química , Hormona Paratiroidea/metabolismo , Receptores Acoplados a Proteínas G , Osteoporosis/tratamiento farmacológico
5.
Med Sci Monit ; 29: e938912, 2023 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-36922715

RESUMEN

BACKGROUND This study aimed to evaluate the safety and efficacy of portal vein puncture with a new guidance system using double C-arm digital subtraction angiography (DSA) during transjugular intrahepatic portosystemic shunt (TIPS) placement. MATERIAL AND METHODS The procedure details of TIPS placements performed on 39 patients in our center between January and December 2021 were retrospectively analyzed. The procedure was performed under double C-arm DSA guidance (study group) and C-arm DSA (control group) in 18 and 21 patients, respectively. We analyzed the procedure's technical success, duration of the overall procedure, portal vein puncture, fluoroscopy, radiation exposure, complications, and mortality and morbidity rates 30 days after the procedure. RESULTS TIPS placement was performed successfully in all patients. The mean portal vein puncture time in the study group (9±5.7 min) was significantly shorter than in the control group (33±14.9 min, p=0.02). The complete mean dose area product of the procedure showed no significant differences (study group, 126±53 Gy/cm²; control group. 142±66 Gy/cm²; p=0.42). The intraprocedural complication rates were 0% and 19% in the study and control groups, respectively (p=0.04). The 30-day post-procedural mortality rate in the control group was 4.8% (1/21), with no deaths from technical complications. CONCLUSIONS Double C-arm DSA guidance is a safe and effective method to assist TIPS placement. This approach may result in shorter portal vein puncture time and lower intraprocedural complication rates.


Asunto(s)
Derivación Portosistémica Intrahepática Transyugular , Humanos , Derivación Portosistémica Intrahepática Transyugular/métodos , Angiografía de Substracción Digital , Estudios Retrospectivos , Vena Porta/cirugía , Punciones , Resultado del Tratamiento
6.
Curr Cardiol Rep ; 25(8): 863-878, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37493874

RESUMEN

PURPOSE OF REVIEW: The article aims to investigate the complex relationship between cancer and cardiovascular disease (CVD), with a focus on the effects of cancer treatment on cardiac health. RECENT FINDINGS: Advances in cancer treatment have improved long-term survival rates, but CVD has emerged as a leading cause of morbidity and mortality in cancer patients. The interplay between cancer itself, treatment methods, homeostatic changes, and lifestyle modifications contributes to this comorbidity. Recent research in the field of cardio-oncology has revealed common genetic mutations, risk factors, and metabolic features associated with the co-occurrence of cancer and CVD. This article provides a comprehensive review of the latest research in cardio-oncology, including common genetic mutations, risk factors, and metabolic features, and explores the interactions between cancer treatment and CVD drugs, proposing novel approaches for the management of cancer and CVD.


Asunto(s)
Antineoplásicos , Enfermedades Cardiovasculares , Neoplasias , Humanos , Cardiotoxicidad/etiología , Cardiotoxicidad/tratamiento farmacológico , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Neoplasias/complicaciones , Oncología Médica , Enfermedades Cardiovasculares/etiología , Antineoplásicos/efectos adversos
7.
JAMA ; 330(16): 1534-1545, 2023 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-37874574

RESUMEN

Importance: Tongxinluo, a traditional Chinese medicine compound, has shown promise in in vitro, animal, and small human studies for myocardial infarction, but has not been rigorously evaluated in large randomized clinical trials. Objective: To investigate whether Tongxinluo could improve clinical outcomes in patients with ST-segment elevation myocardial infarction (STEMI). Design, Setting, and Participants: Randomized, double-blind, placebo-controlled clinical trial was conducted among patients with STEMI within 24 hours of symptom onset from 124 hospitals in China. Patients were enrolled from May 2019 to December 2020; the last date of follow-up was December 15, 2021. Interventions: Patients were randomized 1:1 to receive either Tongxinluo or placebo orally for 12 months (a loading dose of 2.08 g after randomization, followed by the maintenance dose of 1.04 g, 3 times a day), in addition to STEMI guideline-directed treatments. Main Outcomes and Measures: The primary end point was 30-day major adverse cardiac and cerebrovascular events (MACCEs), a composite of cardiac death, myocardial reinfarction, emergent coronary revascularization, and stroke. Follow-up for MACCEs occurred every 3 months to 1 year. Results: Among 3797 patients who were randomized, 3777 (Tongxinluo: 1889 and placebo: 1888; mean age, 61 years; 76.9% male) were included in the primary analysis. Thirty-day MACCEs occurred in 64 patients (3.4%) in the Tongxinluo group vs 99 patients (5.2%) in the control group (relative risk [RR], 0.64 [95% CI, 0.47 to 0.88]; risk difference [RD], -1.8% [95% CI, -3.2% to -0.6%]). Individual components of 30-day MACCEs, including cardiac death (56 [3.0%] vs 80 [4.2%]; RR, 0.70 [95% CI, 0.50 to 0.99]; RD, -1.2% [95% CI, -2.5% to -0.1%]), were also significantly lower in the Tongxinluo group than the placebo group. By 1 year, the Tongxinluo group continued to have lower rates of MACCEs (100 [5.3%] vs 157 [8.3%]; HR, 0.64 [95% CI, 0.49 to 0.82]; RD, -3.0% [95% CI, -4.6% to -1.4%]) and cardiac death (85 [4.5%] vs 116 [6.1%]; HR, 0.73 [95% CI, 0.55 to 0.97]; RD, -1.6% [95% CI, -3.1% to -0.2%]). There were no significant differences in other secondary end points including 30-day stroke; major bleeding at 30 days and 1 year; 1-year all-cause mortality; and in-stent thrombosis (<24 hours; 1-30 days; 1-12 months). More adverse drug reactions occurred in the Tongxinluo group than the placebo group (40 [2.1%] vs 21 [1.1%]; P = .02), mainly driven by gastrointestinal symptoms. Conclusions and Relevance: In patients with STEMI, the Chinese patent medicine Tongxinluo, as an adjunctive therapy in addition to STEMI guideline-directed treatments, significantly improved both 30-day and 1-year clinical outcomes. Further research is needed to determine the mechanism of action of Tongxinluo in STEMI. Trial Registration: ClinicalTrials.gov Identifier: NCT03792035.


Asunto(s)
Medicamentos Herbarios Chinos , Infarto del Miocardio con Elevación del ST , Femenino , Humanos , Masculino , Persona de Mediana Edad , Medicina Tradicional China , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio con Elevación del ST/tratamiento farmacológico , Accidente Cerebrovascular , Medicamentos Herbarios Chinos/uso terapéutico , Método Doble Ciego , Estudios de Seguimiento , Enfermedades Cardiovasculares
8.
J Dairy Sci ; 105(8): 6749-6759, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35840408

RESUMEN

High mortality and involuntary culling rates cause great economic losses to the worldwide dairy cattle industry. However, there is low emphasis on wellness traits in replacement animals (dairy calves and replacement heifers) during their development stages in modern dairy cattle breeding programs. Therefore, the main objectives of this study were to estimate genetic parameters of wellness traits in replacement cattle (replacement wellness traits) and obtain their genetic correlations with 12 cow health and longevity traits in the Chinese Holstein population. Seven replacement wellness traits were analyzed, including birth weight, survival from 3 to 60 d (Sur1), survival from 61 to 365 d (Sur2), survival from 366 d to the first calving (Sur3), calf diarrhea, calf pneumonia, and calf serum total protein (STP). Single and bivariate animal models were employed to estimate (co)variance components using the data from 189,980 Holstein cattle. The genetic correlations between replacement wellness traits and cow longevity, health traits were calculated by employing bivariate models, including 6 longevity traits and 6 health traits (clinical mastitis, metritis, ketosis, displaced abomasum, milk fever, and hoof health or hoof disease). The estimated heritabilities (± SE) were 0.335 (± 0.008), 0.088 (± 0.005), 0.166 (± 0.006), 0.102 (±0 .006), 0.048 (± 0.003), 0.063 (± 0.004), and 0.170 (± 0.019) for birth weight, Sur1, Sur2, Sur3, pneumonia, diarrhea, and STP, respectively. The majority of the genetic correlations among the 7 replacement wellness traits were negligible. The genetic correlations among Sur1, Sur2, and Sur3 ranged from 0.112 (Sur1 and Sur3) to 0.445 (Sur1 and Sur2) when fitting a linear model (estimates in the observed scale), and from 0.560 (Sur1 and Sur3) to 0.773 (Sur1 and Sur2) when fitting a threshold model (estimates in the liability scale). The genetic correlations between replacement wellness and cow longevity were low (absolute value lower than 0.30), but some of them were significantly different from zero. Compared with other replacement wellness traits, Sur3 and STP had relatively high genetic correlations with cow longevity. Replacement wellness traits are heritable and can be improved through direct genetic and genomic selection. The results from the current study will contribute for better balancing dairy cattle breeding goals to genetically improve dairy cattle wellness in the period from birth to first calving.


Asunto(s)
Enfermedades de los Bovinos , Longevidad , Animales , Peso al Nacer , Bovinos/genética , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/genética , Diarrea/veterinaria , Femenino , Lactancia/genética , Longevidad/genética , Leche
9.
J Biol Chem ; 295(11): 3576-3589, 2020 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-32029476

RESUMEN

It has been well-established that the deubiquitinating enzyme ubiquitin-specific peptidase 7 (USP7) supports cancer growth by up-regulating multiple cellular pathways, including Wnt/ß-catenin signaling. Therefore, considerable efforts are directed at identifying and developing USP7 inhibitors. Here, we report that sesquiterpene lactone parthenolide (PTL) inhibits USP7 activity, assessed with deubiquitinating enzyme activity assays, including fluorogenic Ub-AMC/Ub-Rho110, Ub-VME/PA labeling, and Di-Ub hydrolysis assays. Further investigations using cellular thermal shift (CETSA), surface plasmon resonance (SPR), and mass spectrum (MS) assays revealed that PTL directly interacts with USP7. Consistent with the role of USP7 in stimulating Wnt signaling and carcinogenesis, PTL treatment inhibited the activity of Wnt signaling partly by destabilizing ß-catenin. Moreover, using cell viability assays, we found that PTL suppresses the proliferation of colorectal cancer cells and induces apoptosis in these cells. Additionally, we examined the effects of two other sesquiterpene lactones (costunolide and α-santonin) on USP7 and Wnt signaling and found that α-methylene-γ-butyrolactone may provide a scaffold for future USP7 inhibitors. In summary, our findings reveal that PTL inhibits USP7 activity, identifying a potential mechanism by which PTL suppresses Wnt/ß-catenin signaling. We further suggest that sesquiterpene lactones might represent a suitable scaffold for developing USP7 inhibitors and indicate that PTL holds promise as an anticancer agent targeting aberrant USP7/Wnt signaling.


Asunto(s)
Neoplasias Colorrectales/enzimología , Neoplasias Colorrectales/patología , Sesquiterpenos/farmacología , Peptidasa Específica de Ubiquitina 7/antagonistas & inhibidores , Vía de Señalización Wnt/efectos de los fármacos , 4-Butirolactona/análogos & derivados , 4-Butirolactona/química , 4-Butirolactona/farmacología , Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Neoplasias Colorrectales/genética , Regulación hacia Abajo/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células HEK293 , Humanos , Proteolisis/efectos de los fármacos , Sesquiterpenos/química , Peptidasa Específica de Ubiquitina 7/metabolismo , Ubiquitinación/efectos de los fármacos , beta Catenina/metabolismo
10.
BMC Endocr Disord ; 21(1): 140, 2021 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-34215247

RESUMEN

BACKGROUND: In patients with established HF, low triiodothyronine syndrome (LT3S) is commonly present, and N-terminal pro-B-type natriuretic peptide (NT-proBNP) is a useful marker for predicting death. This study was aimed to evaluate the prognostic value of LT3S in combination with NT-proBNP for risk of death in patients with heart failure (HF). METHODS: A total of 594 euthyroid patients hospitalized with acute decompensated HF were enrolled by design. Of these patients, 27 patients died during hospitalization and 100 deaths were identified in patients discharged alive during one year follow-up. Patients were divided into 2 groups on the base of the reference ranges of free T3 (FT3) levels: LT3S group (FT3 < 2.3pg/mL, n = 168) and non-LT3S group (FT3 ≥ 2.3pg/mL, n = 426). RESULTS: In multivariable Cox regression, LT3S was significantly associated with 1 year all-cause mortality (adjusted hazard ratio, 1.85; 95 % confidence interval [CI], 1.21 to 2.82; P = 0.005), but not significant for in-hospital mortality (adjusted hazard ratio, 1.58; 95 % CI, 1.58 to 2.82; P = 0.290) after adjustment for clinical variables and NT-proBNP. Addition of LT3S and NT-proBNP to the prediction model with clinical variables significantly improved the C statistic for predicting 1 year all-cause mortality. CONCLUSIONS: In patients with acute decompensated HF, the combination of LT3S and NT-proBNP improved prediction for 1 year all-cause mortality beyond established risk factors, but was not strong enough for in-hospital mortality.


Asunto(s)
Síndromes del Eutiroideo Enfermo/sangre , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/mortalidad , Péptido Natriurético Encefálico/análisis , Fragmentos de Péptidos/análisis , Pruebas de Función de la Tiroides , Enfermedad Aguda/mortalidad , Anciano , Anciano de 80 o más Años , Biomarcadores/análisis , Biomarcadores/sangre , Síndromes del Eutiroideo Enfermo/complicaciones , Síndromes del Eutiroideo Enfermo/fisiopatología , Femenino , Mortalidad Hospitalaria , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales , Factores de Riesgo
11.
Int J Clin Pract ; 75(12): e14824, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34492131

RESUMEN

AIM: The purpose of this study was to investigate the impact of J-CTO (Multicenter Chronic Total Occlusion Registry of Japan) score on in-stent chronic total occlusion (IS-CTO) percutaneous coronary intervention (PCI). METHODS: A retrospective data collection was conducted on 474 patients undergoing a difficult IS-CTO PCI from January 2015 to December 2018. The primary endpoint (major adverse cardiovascular events [MACE]) consisted of target-vessel myocardial infarction (MI), cardiac death or ischemia-driven target-vessel revascularisation (TVR) at follow-up. The cut-off points were estimated by the Youden index. RESULTS: The overall procedural success rate was 77.6%. On multivariable analysis, factors including proximal bending (beta coefficient [ß] = 3.465), tortuosity (ß = 3.064), stent under expansion (ß = 3.109) and poor distal landing zone (ß = 1.959) were associated with technical failure via antegrade approach but not the J-CTO score (OR = 0.632; 95% CI [0.352-1.134]; P = .124). After a median follow-up of 30 months (interquartile range: 17-42 months), multivariable analysis revealed that receiving >18 months of dual antiplatelet therapy (DAPT) was an independent predictor of decreased risk of MACE (HR: 2.690; 95% CI: 1.346-5.347; P = .005). But the J-CTO score was not an independent predictor of MACE (HR: 1.018; 95% CI: 0.728-1.424; P = .917). CONCLUSIONS: J-CTO score system is not a helpful tool to predict the technical success of difficult IS-CTO PCI via antegrade approach, nor does it correlate with long-term outcomes in patients undergoing IS-CTO PCI. Nevertheless, factors associated with technical failure include proximal bending of ≥30 degrees, under expansion of ≥10 mm, moderate or severe tortuosity (bending) ≥20 and poor distal target. Long-term DAPT therapy contributes significantly to decreased MACE.


Asunto(s)
Oclusión Coronaria , Intervención Coronaria Percutánea , Enfermedad Crónica , Angiografía Coronaria , Oclusión Coronaria/cirugía , Humanos , Sistema de Registros , Estudios Retrospectivos , Factores de Riesgo , Stents/efectos adversos , Resultado del Tratamiento
12.
Biochem Biophys Res Commun ; 525(2): 303-307, 2020 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-32089263

RESUMEN

Microtubules are involved in celluar processes of movement, intracellular trafficking and mitosis, thus microtubule-targeting agents have been widely used in cancer therapy. Herein, we report isopenicin A, a novel meroterpenoid isolated from the plant endophytic fungus of Penicillium sp. sh18, as a novel microtubule binding molecule that efficiently depolymerizes microtubule polymerization to evoke G2/M cell cycle arrest and subsequent cell apoptosis, contributing to proliferation inhibition of human tumor cell lines. The discovery of isopenicin A provides a new chemotype for discovery and development of promising microtubule inhibitors.


Asunto(s)
Antineoplásicos/aislamiento & purificación , Penicillium/química , Moduladores de Tubulina/aislamiento & purificación , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Humanos , Microtúbulos/metabolismo , Polimerizacion/efectos de los fármacos , Terpenos/aislamiento & purificación , Terpenos/farmacología , Tubulina (Proteína)/metabolismo , Moduladores de Tubulina/farmacología
13.
Acta Pharmacol Sin ; 41(10): 1328-1336, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32235863

RESUMEN

Relaxin/insulin-like family peptide receptor 4 (RXFP4) is a class A G protein-coupled receptor (GPCR), and insulin-like peptide 5 (INSL5) is its endogenous ligand. Although the precise physiological role of INSL5/RXFP4 remains elusive, a number of studies have suggested it to be a potential therapeutic target for obesity and other metabolic disorders. Since selective agonists of RXFP4 are scarcely available and peptidic analogs of INSL5 are hard to make, we conducted a high-throughput screening campaign against 52,000 synthetic and natural compounds targeting RXFP4. Of the 109 initial hits discovered, only 3 compounds were confirmed in secondary screening, with JK0621-D008 displaying the best agonism at human RXFP4. Its S-configuration stereoisomer (JK1) was subsequently isolated and validated by a series of bioassays, demonstrating a consistent agonistic effect in cells overexpressing RXFP4. This scaffold may provide a valuable tool to further explore the biological functions of RXFP4.


Asunto(s)
Receptores Acoplados a Proteínas G/agonistas , Receptores de Péptidos/agonistas , Bibliotecas de Moléculas Pequeñas/farmacología , Animales , Células CHO , Cricetulus , Células HEK293 , Ensayos Analíticos de Alto Rendimiento , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Ratones , Bibliotecas de Moléculas Pequeñas/toxicidad
14.
Molecules ; 24(6)2019 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-30909473

RESUMEN

Deregulation of the Wnt signaling pathway leads to colorectal cancer progression. Natural dietary compounds serve as promising candidates for development as chemopreventive agents by suppressing the Wnt/ß-catenin signaling pathway. Physalis peruviana-derived 4ßHWE showed a significant inhibitory activity with a calculated IC50 of 0.09 µΜ in a screening of novel inhibitors of Wnt signaling with the dual-luciferase reporter assay. This study investigated the anti-tumor effect of 4ßHWE and the potential Wnt signaling inhibitory mechanism. Both the western blot analysis and immunofluorescence assay showed that 4ßHWE promoted the phosphorylation and degradation of ß-catenin and the subsequent inhibition of its nuclear translocation to attenuate the endogenous Wnt target gene expression in colorectal cancer (CRC) cells. The cell viability assay indicated that 4ßHWE preferentially inhibited the proliferation of CRC compared with CCD-841-CoN, a normal human colonic epithelial cell line. 4ßHWE-mediated G0/G1 cell cycle arrest and apoptosis induction contributed to the suppression of the proliferation of CRC in the cell cycle and Annexin V-FITC/Propidium Iodide apoptosis analysis. Moreover, in vivo, 4ßHWE dramatically inhibited tumor growth in HCT116 xenografts by attenuating the Wnt/ß-catenin signaling pathway. In conclusion, our study suggested that 4ßHWE could be of potential use in anti-tumor agent development as a novel Wnt signaling inhibitor.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Physalis/química , Extractos Vegetales/farmacología , Witanólidos/farmacología , Vía de Señalización Wnt/efectos de los fármacos , Animales , Antineoplásicos Fitogénicos/química , Apoptosis/efectos de los fármacos , Biomarcadores , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Neoplasias Colorrectales/metabolismo , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Humanos , Ratones , Estructura Molecular , Extractos Vegetales/química , Relación Estructura-Actividad , Witanólidos/química
15.
Sheng Li Xue Bao ; 71(1): 149-155, 2019 Feb 25.
Artículo en Zh | MEDLINE | ID: mdl-30778513

RESUMEN

Cognitive control refers to the brain functions that regulate variously specific mental activities in terms of task goal, forming the basis of goal-guided behaviors. In the last decade, our team devoted to investigating the neural mechanisms of basic functions of cognitive control, i.e., monitoring, controlling, and switching. We published a series of papers on the temporal course of monitoring initiating cognitive control and its mechanisms, the influential scope of controlling and new controlling mechanisms, brain networks related to controlling efficiency, brain hubs and neural dynamic encoding of switching. This paper reviews the related studies and further extracts their theoretical significance. In the future, more attention should be paid on causal studies, studies on functional implementation of cognitive control, and transfer-application studies, by which we expect to deeply elucidate neural mechanisms of cognitive control.


Asunto(s)
Mapeo Encefálico , Encéfalo/fisiología , Cognición , Humanos
16.
Sheng Li Xue Bao ; 71(4): 562-574, 2019 Aug 25.
Artículo en Zh | MEDLINE | ID: mdl-31440753

RESUMEN

The influence of reward on behavior is one of the hottest research subjects in psychological research. Reward-induced motivation promotes the performance of the participants. In the field of emotional processing, the reward can influence the individual's processing of emotional information, but previous studies have not directly discussed the effect of reward on emotional regulation. The present study focused on whether emotional regulation ability would be improved under the reward condition. Experiment 1 and 2 investigated the effect of reward on negative emotional down-regulation and positive emotional up-regulation respectively. In experiment 1, monetary reward stimulation was introduced on the basis of the classic emotion regulation paradigm, and the subjects were asked to regulate their negative emotion under the condition of reward or non-reward, and evaluate their current affective state subsequently. Similar to experiment 1, experiment 2 required subjects to up-regulate positive emotions under the condition of reward or non-reward. The results of experiment 1 showed that under the reward condition, the negative emotional regulation effect was significantly higher than that under the non-reward condition (P < 0.05). Experiment 2 also showed that compared to non-reward condition, the positive emotion regulation effect was significantly increased under the reward condition (P < 0.05). These results suggested that compared to non-reward condition, participants can regulate their emotion better under the condition of the reward. It is worth noting that the results of Experiment 1 and 2 may be caused by the incentive motivation induced by monetary stimulus, or the positive emotion caused by positive value of money information. Therefore, we carried out experiment 3 and 4 to explore whether the positive emotions induced by money itself can influence the emotional regulation of individuals. In experiment 3, the money pictures were used to induce the positive emotions of subjects, and the subjects were asked to regulate their negative emotion after the presence of money pictures or non-monetary picture, and evaluate their current affective state subsequently. Similarly, experiment 4 required subjects to regulate their positive emotion after the presence of money pictures. The results of experiment 3 and 4 showed that there was no significant difference in the subjects' scores of emotional pleasantness after the presence of money pictures or non-monetary picture (P < 0.05). The results of experiment 3 and 4 excluded the possibility that the positive emotions induced by simple money stimulus pictures could improve individual's emotional regulation ability. To sum up, the improvement of individual's emotional regulation ability was indeed driven by reward motivation in this study, that is, the motivation induced by reward can effectively promote individual's emotional regulation ability.


Asunto(s)
Emociones , Motivación , Recompensa , Humanos
17.
Biochem Biophys Res Commun ; 503(4): 3057-3063, 2018 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-30144974

RESUMEN

The natural killer group 2D (NKG2D) receptor on natural killer (NK) cells play an important role in immunosurveillance to cancer cells, which could mediate the eradication of tumor cells through specific interactions with NKG2D ligands on tumor cells. Here we report one natural compound aurovertin B from basidiomycete Albatrellus confluens significantly stimulates the expression of NKG2D ligands on tumor cells, which greatly sensitizes its recognition and lysis by NK cell. It is completely a novel role for aurovertin B to target tumor cells to death mediated by NK cells and our findings indicate aurovertin B may deserve further development as sensitizing agent in NK cell mediated cancer immunotherapy.


Asunto(s)
Antineoplásicos/farmacología , Aurovertinas/farmacología , Neoplasias Colorrectales/tratamiento farmacológico , Citotoxicidad Inmunológica/efectos de los fármacos , Péptidos y Proteínas de Señalización Intercelular/inmunología , Células Asesinas Naturales/efectos de los fármacos , Antineoplásicos/química , Aurovertinas/química , Basidiomycota/química , Línea Celular Tumoral , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/inmunología , Proteínas Ligadas a GPI/genética , Proteínas Ligadas a GPI/inmunología , Humanos , Péptidos y Proteínas de Señalización Intercelular/genética , Células Asesinas Naturales/inmunología , Regulación hacia Arriba/genética
18.
Small ; 14(16): e1704169, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29520974

RESUMEN

The oxygen reduction reaction (ORR) is under intense research due to its significance in energy storage and conversion processes. Recent studies show that interconnected and hierarchically porous structures can further enhance ORR kinetics as well as catalyst durability, but their preparation can be quite time and/or chemical consuming. Here, a simple approach is reported to prepare such complex structures by pyrolyzing composites containing NaCl and ZIF-8. The templating effect of molten NaCl connects ZIF-8 particles into web-like carbon networks. During ORR activity measurements, it achieves a 0.964 V onset potential and a 38 mV dec-1 Tafel slope, which are comparable to those of the benchmark Pt/C (0.979 V and 40 mV dec-1 ). Due to the metal-free feature, this catalyst exhibits a 16 mV shift in half-wave potential after a 10 000-cycle durability test, which is only 60% of that of Pt/C. The catalyst is also tested in Zn-air batteries and the assemblies are able to work at above 1.2 V for 140 h, which triples the life held by those with Pt/C. This study demonstrates a facile strategy to prepare metal-free ORR catalysts with interconnectivity and hierarchical porosity, and proves their great potentials in ORR catalysis and Zn-air batteries.

19.
J Surg Res ; 232: 247-256, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30463725

RESUMEN

BACKGROUND: The aim of this study was to determine whether internal or external drainage with a pancreatic duct stent is the optimal pancreaticojejunostomy method to prevent pancreatic fistula (PF) after pancreaticoduodenectomy (PD) for subgroups of patients at high risk for PF. MATERIALS AND METHODS: A total of 495 patients who underwent PD were reviewed. Univariate and multivariate analyses were used to identify risk factors for PF after PD. We further compared the incidence of PF and outcomes between the internal and external drainage groups for subgroups of patients at high risk for PF. RESULTS: There was no difference in the incidence of complications according to the Clavien-Dindo classification or the rate of PF after PD in both groups (P = 0.961 and P = 0.505, respectively). The incidence of mortality was 3.8% in the internal drainage group and 3.9% in the external drainage group (P = 0.980). Univariate and multivariate analyses identified male gender (odds ratio [OR] = 2.93; 95% confidence interval [CI], 1.78-4.83; P = 0.000), pancreatic duct diameter (<3 mm) (OR = 2.58; 95% CI, 1.57-4.23; P = 0.000), and soft pancreatic texture (OR = 2.92; 95% CI, 1.71-4.98; P = 0.000) as independent risk factors for PF after PD. No differences in the incidence of PF for the subgroups of patients with one, two, or three risk factors were observed between the internal and external drainage groups (P = 0.334, P = 1.000, and P = 0.936, respectively). No differences in total complications, delayed gastric emptying, postpancreatectomy hemorrhage, biliary fistula, infection complications, reoperation, perioperative mortality, or postoperative hospital stay were noted. In addition, liquid loss and tube-related complications occurred in the external drainage group. CONCLUSIONS: Internal drainage is the optimal method to prevent PF after PD for subgroups of patients at high risk for PF because the surgical procedure is simple and prevents liquid loss and tube-related complications associated with external drainage. However, no differences in the incidence of PF and other complications after PD were observed between the two approaches.


Asunto(s)
Drenaje/métodos , Conductos Pancreáticos , Fístula Pancreática/prevención & control , Pancreaticoduodenectomía/métodos , Pancreatoyeyunostomía/métodos , Stents , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fístula Pancreática/epidemiología , Complicaciones Posoperatorias/prevención & control , Factores de Riesgo
20.
J Gastroenterol Hepatol ; 32(5): 975-980, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28072910

RESUMEN

Constantly challenged by luminal bacteria, intestinal epithelium forms both a physical and biochemical defense against pathogens. Besides, intestinal epithelium senses dynamic and continuous changes in luminal environment and transmits signals to subjacent immune cells accordingly. It has been long accepted that adaptive immune cells fulfill their roles partly by modulating function of intestinal epithelial cells. Recent studies have brought up the proposal that intestinal epithelial cells also actively participate in the regulation of adaptive immunity, especially CD4+ adaptive T cells, which indicates that there is reciprocal crosstalk between intestinal epithelial cells and adaptive immune cells, and the crosstalk may play important role in intestinal mucosal immunity. This Review makes a comprehensive summary about crosstalk between intestinal epithelial cells and CD4+ adaptive T cells in intestinal immunity. Special attention would be given to their implications in inflammatory bowel disease pathogenesis and potential therapeutic targets.


Asunto(s)
Inmunidad Adaptativa/inmunología , Linfocitos T CD4-Positivos/inmunología , Células Epiteliales/inmunología , Mucosa Intestinal/citología , Mucosa Intestinal/inmunología , Progresión de la Enfermedad , Humanos , Enfermedades Inflamatorias del Intestino/inmunología , Enfermedades Inflamatorias del Intestino/terapia , Terapia Molecular Dirigida
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