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1.
Immunity ; 57(3): 528-540.e6, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38417442

RESUMEN

RNA splicing is involved in cancer initiation and progression, but how it influences host antitumor immunity in the metabolically abnormal tumor microenvironment (TME) remains unclear. Here, we demonstrate that lactate modulates Foxp3-dependent RNA splicing to maintain the phenotypic and functional status of tumor-infiltrating regulatory T (Treg) cells via CTLA-4. RNA splicing in Treg cells was correlated with the Treg cell signatures in the TME. Ubiquitin-specific peptidase 39 (USP39), a component of the RNA splicing machinery, maintained RNA-splicing-mediated CTLA-4 expression to control Treg cell function. Mechanistically, lactate promoted USP39-mediated RNA splicing to facilitate CTLA-4 expression in a Foxp3-dependent manner. Moreover, the efficiency of CTLA-4 RNA splicing was increased in tumor-infiltrating Treg cells from patients with colorectal cancer. These findings highlight the immunological relevance of RNA splicing in Treg cells and provide important insights into the environmental mechanism governing CTLA-4 expression in Treg cells.


Asunto(s)
Neoplasias , Linfocitos T Reguladores , Humanos , Antígeno CTLA-4 , Factores de Transcripción Forkhead/genética , Ácido Láctico/metabolismo , Linfocitos Infiltrantes de Tumor , Neoplasias/genética , Neoplasias/metabolismo , Microambiente Tumoral , Proteasas Ubiquitina-Específicas/metabolismo
2.
Mol Cell ; 81(5): 940-952.e5, 2021 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-33434504

RESUMEN

STING-dependent cytosolic DNA sensing in dendritic cells (DCs) initiates antitumor immune responses, but how STING signaling is metabolically regulated in the tumor microenvironment remains unknown. Here, we show that oxidative stress is required for STING-induced DC antitumor function through a process that directs SUMO-specific protease 3 (SENP3) activity. DC-specific deletion of Senp3 drives tumor progression by blunting STING-dependent type-I interferon (IFN) signaling in DCs and dampening antitumor immune responses. DC-derived reactive oxygen species (ROS) trigger SENP3 accumulation and the SENP3-IFI204 interaction, thereby catalyzing IFI204 deSUMOylation and boosting STING signaling activation in mice. Consistently, SENP3 senses ROS to facilitate STING-dependent DC activity in tissue samples from colorectal cancer patients. Our results reveal that oxidative stress as a metabolic regulator promotes STING-mediated DC antitumor immune responses and highlights SENP3 as an overflow valve for STING signaling induction in the metabolically abnormal tumor microenvironment.


Asunto(s)
Neoplasias Colorrectales/genética , Cisteína Endopeptidasas/genética , Células Dendríticas/inmunología , Regulación Neoplásica de la Expresión Génica , Proteínas de la Membrana/genética , Proteínas Nucleares/genética , Fosfoproteínas/genética , Aloinjertos , Animales , Línea Celular Tumoral , Proliferación Celular , Neoplasias Colorrectales/inmunología , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/patología , Cisteína Endopeptidasas/inmunología , Células Dendríticas/patología , Femenino , Células HEK293 , Humanos , Interferón Tipo I/genética , Interferón Tipo I/inmunología , Proteínas de la Membrana/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Trasplante de Neoplasias , Proteínas Nucleares/antagonistas & inhibidores , Proteínas Nucleares/inmunología , Estrés Oxidativo , Fosfoproteínas/antagonistas & inhibidores , Fosfoproteínas/inmunología , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Especies Reactivas de Oxígeno/inmunología , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Análisis de Supervivencia , Microambiente Tumoral/genética , Microambiente Tumoral/inmunología
3.
J Biol Chem ; 300(6): 107299, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38641063

RESUMEN

ABCG2, a member of the ABC transporter superfamily, is overexpressed in many human tumors and has long been studied for its ability to export a variety of chemotherapeutic agents, thereby conferring a multidrug resistance (MDR) phenotype. However, several studies have shown that ABCG2 can also confer an MDR-independent survival advantage to tumor cells exposed to stress. While investigating the mechanism by which ABCG2 enhances survival in stressful milieus, we have identified a physical and functional interaction between ABCG2 and SLC1A5, a member of the solute transporter superfamily and the primary transporter of glutamine in cancer cells. This interaction was accompanied by increased glutamine uptake, increased glutaminolysis, and rewired cellular metabolism, as evidenced by an increase in key metabolic enzymes and alteration of glutamine-dependent metabolic pathways. Specifically, we observed an increase in glutamine metabolites shuttled to the TCA cycle, and an increase in the synthesis of glutathione, accompanied by a decrease in basal levels of reactive oxygen species and a marked increase in cell survival in the face of oxidative stress. Notably, the knockdown of SLC1A5 or depletion of exogenous glutamine diminished ABCG2-enhanced autophagy flux, further implicating this solute transporter in ABCG2-mediated cell survival. This is, to our knowledge, the first report of a functionally significant physical interaction between members of the two major transporter superfamilies. Moreover, these observations may underlie the protective role of ABCG2 in cancer cells under duress and suggest a novel role for ABCG2 in the regulation of metabolism in normal and diseased states.


Asunto(s)
Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Supervivencia Celular , Glutamina , Antígenos de Histocompatibilidad Menor , Proteínas de Neoplasias , Estrés Oxidativo , Humanos , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/genética , Proteínas de Neoplasias/metabolismo , Proteínas de Neoplasias/genética , Glutamina/metabolismo , Antígenos de Histocompatibilidad Menor/metabolismo , Antígenos de Histocompatibilidad Menor/genética , Transportador 1 de Aminoácidos Excitadores/metabolismo , Transportador 1 de Aminoácidos Excitadores/genética , Línea Celular Tumoral , Neoplasias/metabolismo , Neoplasias/patología , Neoplasias/genética , Especies Reactivas de Oxígeno/metabolismo , Sistema de Transporte de Aminoácidos ASC
4.
Nano Lett ; 24(1): 67-73, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38149785

RESUMEN

Two-dimensional transition metal nitrides offer intriguing possibilities for achieving novel electronic and mechanical functionality owing to their distinctive and tunable bonding characteristics compared to other 2D materials. We demonstrate here the enabling effects of strong bonding on the morphology and functionality of 2D tungsten nitrides. The employed bottom-up synthesis experienced a unique substrate stabilization effect beyond van-der-Waals epitaxy that favored W5N6 over lower metal nitrides. Comprehensive structural and electronic characterization reveals that monolayer W5N6 can be synthesized at large scale and shows semimetallic behavior with an intriguing indirect band structure. Moreover, the material exhibits exceptional resilience against mechanical damage and chemical reactions. Leveraging these electronic properties and robustness, we demonstrate the application of W5N6 as atomic-scale dry etch stops that allow the integration of high-performance 2D materials contacts. These findings highlight the potential of 2D transition metal nitrides for realizing advanced electronic devices and functional interfaces.

5.
Ann Surg ; 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38385254

RESUMEN

OBJECTIVE: This study aimed to evaluate the effect of perioperative dexamethasone on postoperative complications after pancreaticoduodenectomy. BACKGROUND: The glucocorticoid dexamethasone has been shown to improve postoperative outcomes in surgical patients, but its effects on postoperative complications after pancreaticoduodenectomy are unclear. METHODS: This multicenter, double-blind, randomized controlled trial was conducted in four Chinese high-volume pancreatic centers. Adults undergoing elective pancreaticoduodenectomy were randomized to receive either 0.2 mg/kg dexamethasone or a saline placebo as an intravenous bolus within 5 minutes after anesthesia induction. The primary outcome was the Comprehensive Complication Index (CCI) score within 30 days after the operation, analyzed using the modified intention-to-treat principle. RESULTS: Among 428 patients for eligibility, 300 participants were randomized and 265 were included in the modified intention-to-treat analyses. 134 patients received dexamethasone and 131 patients received a placebo. The mean (SD) CCI score was 14.0 (17.5) in the dexamethasone group and 17.9 (20.3) in the placebo group (mean difference, -3.8; 95% CI, -8.4 to 0.7; P=0.100). The incidence of major complications (Clavien-Dindo grade ≥III) (12.7% vs. 16.0%, risk ratio 0.79; 95% CI, 0.44 to 1.43; P=0.439) and postoperative pancreatic fistula (25.4% vs. 31.3%, risk ratio 0.81; 95% CI, 0.55 to 1.19; P=0.286) were not significantly different between the two groups. In the stratum of participants with a main pancreatic duct ≤3 mm (n=202), the CCI score was significantly lower in the dexamethasone group (mean difference, -6.4; 95% CI, -11.2 to -1.6; P=0.009). CONCLUSION: Perioperative dexamethasone did not significantly reduce postoperative complications within 30 days after pancreaticoduodenectomy.

6.
Small ; 20(26): e2310838, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38214694

RESUMEN

Although bioactive compounds (BCs) have many important functions, their applications are greatly limited due to their own defects. The development of nanocarriers (NCs) technology has gradually overcome the defects of BCs. NCs are equally important as BCs to some extent. Self-assembly (SA) methods to build NCs have many advantages than chemical methods, and SA has significant impact on the structure and function of NCs. However, the relationship among SA mechanism, structure, and function has not been given enough attention. Therefore, from the perspective of bottom-up building mechanism, the concept of SA-structure-function of NCs is emphasized to promote the development of SA-based NCs. First, the conditions and forces for occurring SA are introduced, and then the SA basis and molecular mechanism of protein, polysaccharide, and lipid are summarized. Then, varieties of the structures formed based on SA are introduced in detail. Finally, facing the defects of BCs and how to be well solved by NCs are also elaborated. This review attempts to describe the great significance of constructing artificial NCs to deliver BCs from the aspects of SA-structure-function, so as to promote the development of SA-based NCs and the wide application of BCs.


Asunto(s)
Portadores de Fármacos , Sistemas de Liberación de Medicamentos , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/métodos , Nanopartículas/química , Humanos , Lípidos/química
7.
Small ; : e2403397, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38925625

RESUMEN

To explore novel electrode materials with in-depth elucidation of initial coulombic efficiency (ICE), kinetics, and charge storage mechanisms is of great challenge for Na-ion storage. Herein, a novel 3D antiperovskite carbide Ni3ZnC0.7@rGO anode coupled with ether-based electrolyte is reported for fast Na-ion storage, exhibiting superior performance than ester-based electrolyte. Electrochemical tests and density functional theory (DFT) calculations show that Ni3ZnC0.7@rGO anode with ether-based electrolyte can promote charge/ion transport and lower Na+ diffusion energy barrier, thereby improving ICE, reversible capacity, rate, and cycling performance. Cross-sectional-morphology and depth profiling surface chemistry demonstrate that not only a thinner and more homogeneous reaction interface layer with less side effects but also a superior solid electrolyte interface (SEI) film with a high proportion of inorganic components are formed in the ether-based electrolyte, which accelerates Na+ transport and is the significant reason for the improvement of ICE and other electrochemical properties. Meanwhile, electrochemical and ex situ measurements have revealed conversion, alloying, and co-intercalation hybrid mechanisms of the Ni3ZnC0.7@rGO anode based on ether electrolyte. Interestingly, the Na-ion capacitors (SICs) designed by pairing with activated carbon (AC) cathode exhibit favorable electrochemical performance. Overall, this work provides deep insights on developing advanced materials for fast Na-ion storage.

8.
Small ; : e2403151, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38934338

RESUMEN

Developing high electroactivity ruthenium (Ru)-based electrocatalysts for pH-universal hydrogen evolution reaction (HER) is challenging due to the strong bonding strengths of key Ru─H/Ru─OH intermediates and sluggish water dissociation rates on active Ru sites. Herein, a semi-ionic F-modified N-doped porous carbon implanted with ruthenium nanoclusters (Ru/FNPC) is introduced by a hydrogel sealing-pyrolying-etching strategy toward highly efficient pH-universal hydrogen generation. Benefiting from the synergistic effects between Ru nanoclusters (Ru NCs) and hierarchically F, N-codoped porous carbon support, such synthesized catalyst displays exceptional HER reactivity and durability at all pH levels. The optimal 8Ru/FNPC affords ultralow overpotentials of 17.8, 71.2, and 53.8 mV at the current density of 10 mA cm-2 in alkaline, neutral, and acidic media, respectively. Density functional theory (DFT) calculations elucidate that the F-doped substrate to support Ru NCs weakens the adsorption energies of H and OH on Ru sites and reduces the energy barriers of elementary steps for HER, thus enhancing the intrinsic activity of Ru sites and accelerating the HER kinetics. This work provides new perspectives for the design of advanced electrocatalysts by porous carbon substrate implanted with ultrafine metal NCs for energy conversion applications.

9.
Small ; 20(22): e2311209, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38098342

RESUMEN

Two-dimensional (2D) materials are promising successors for silicon transistor channels in ultimately scaled devices, necessitating significant research efforts to study their behavior at nanoscopic length scales. Unfortunately, current research has limited itself to direct patterning approaches, which limit the achievable resolution to the diffraction limit and introduce unwanted defects into the 2D material. The potential of multi-patterning to fabricate 2D materials features with unprecedented precision and low complexity at large scale is demonstrated here. By combining lithographic patterning of a mandrel and bottom-up self-expansion, this approach enables pattern resolution one order of magnitude below the lithographical resolution. In-depth characterization of the self-expansion double patterning (SEDP) process reveals the ability to manipulate the critical dimension with nanometer precision through a self-limiting and temperature-controlled oxidation process. These results indicate that the SEDP process can regain the quality and morphology of the 2D material, as shown by high-resolution microscopy and optical spectroscopy. This approach is shown to open up new avenues for research into high-performance, ultra-scaled 2D materials devices for future electronics.

10.
Cerebrovasc Dis ; 53(2): 198-204, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37437549

RESUMEN

INTRODUCTION: Stroke has become a major disease that threatens the global population's health and is a major public health problem that needs to be solved in China. Therefore, it is essential to analyze the trend of the mortality of stroke and its epidemic characteristic of stroke death. METHODS: Death cases of stroke were reported to the national death registry system by the medical staff of all medical institutions, and the population data every year were obtained from District or County's Statistic Bureau in Chongqing. They were analyzed to calculate the mortality, age-standardized mortality rate by Chinese standardization population (ASMRC), age-specific mortality, proportion, and annual percent of change (APC) according to the ICD-10 code. ASMRC was based on the standard population of the 6th census in China, 2010. The stroke mortality of each subgroup was compared using the χ2 test. Trend analysis was presented by APC. RESULTS: The crude mortality of stroke increased from 96.29 per 100,000 in 2012 to 115.93 per 100,000 significantly, with the APC of 2.02% (t = 2.82, p = 0.022) in Chongqing. ASMRC of stroke was 56.47 per 100,000 in 2012 and 54.70 per 100,000 in 2021, and its trend change was stable (APC = -0.01, t = 0.07, p = 0.947). The crude mortality of stroke in males was higher than that in females every year (p < 0.05). The death proportion of intracerebral hemorrhage dwindled from 60.53% in 2012 to 49.88% in 2021, whereas the death proportion of ischemic stroke increased from 20.92% in 2012 to 39.96% in 2021. The average age of stroke death was delayed from 73.43 years old in 2012 to 76.52 years old in 2021 significantly (t = 18.12, p < 0.001). The percentage of stroke death at home increased from 75.23% in 2012 to 79.23% in 2021, while the percentage of stroke death at hospitals decreased from 17.89% in 2012 to 15.89% in 2021. CONCLUSION: The crude mortality of stroke surged, and intracerebral hemorrhage was the main death cause of all subtypes. The mortality of stroke in males and rural residents was higher than that in females and urban residents. Most stroke deaths occurred at home. Male and rural residents were crucial populations for stroke prevention and control. There should be improved medical resources in rural areas and enhanced capability of stroke diagnosis and treatment.


Asunto(s)
Accidente Cerebrovascular , Femenino , Humanos , Masculino , Anciano , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/terapia , Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/terapia , Sistema de Registros , Población Rural , China/epidemiología , Población Urbana , Incidencia
11.
Rapid Commun Mass Spectrom ; 38(14): e9763, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-38745395

RESUMEN

OBJECTIVE: Carotid atherosclerosis is a chronic progressive vascular disease that can be complicated by stroke in severe cases. Prompt diagnosis and treatment of high-risk patients are quite difficult due to the lack of reliable clinical biomarkers. This study aimed to explore potential plaque metabolic markers of stroke-prone risk and relevant targets for pharmacological intervention. METHOD: Carotid intima and plaque sample tissues were obtained from 20 patients with cerebrovascular symptoms of carotid origin. An untargeted metabolomics approach based on liquid chromatography-tandem mass spectrometry was utilized to characterize the metabolic profiles of the tissues. Multivariate and univariate analysis tools were used. RESULTS: A total of 154 metabolites were significantly altered in carotid plaque when compared with thickened intima. Of these, 62 metabolites were upregulated, whereas 92 metabolites were downregulated. Support vector machines identified the 15 most important metabolites, such as N-(cyclopropylmethyl)-N'-phenylurea, 9(S)-HOTrE, ACar 12:2, quinoxaline-2,3-dithiol, and l-thyroxine, as biomarkers for high-risk plaques. Metabolic pathway analysis showed that abnormal purine and nucleotide metabolism, amino acid metabolism, glutathione metabolism, and vitamin metabolism may contribute to the occurrence and progression of carotid atherosclerotic plaque. CONCLUSIONS: Our study identifies the biomarkers and related metabolic mechanisms of carotid plaque, which is stroke-prone, and provides insights and ideas for the precise prevention and targeted intervention of the disease.


Asunto(s)
Biomarcadores , Metabolómica , Placa Aterosclerótica , Espectrometría de Masas en Tándem , Humanos , Espectrometría de Masas en Tándem/métodos , Masculino , Femenino , Biomarcadores/análisis , Biomarcadores/metabolismo , Persona de Mediana Edad , Anciano , Placa Aterosclerótica/química , Placa Aterosclerótica/metabolismo , Metabolómica/métodos , Cromatografía Liquida/métodos , Enfermedades de las Arterias Carótidas/metabolismo , Metaboloma
12.
Mol Biol Rep ; 51(1): 636, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38727863

RESUMEN

BACKGROUND: Osteoporosis (OP), characterized by compromised bone integrity and increased fracture risk, poses a significant health challenge. Circular RNAs (circRNAs) have emerged as crucial regulators in various pathophysiological processes, prompting investigation into their role in osteoporosis. This study aimed to elucidate the involvement of circCOX6A1 in OP progression and understand its underlying molecular mechanisms. The primary objective was to explore the impact of circCOX6A1 on bone marrow-derived mesenchymal stem cells (BMSCs) and its potential interactions with miR-512-3p and DYRK2. METHODS: GSE161361 microarray analysis was employed to assess circCOX6A1 expression in OP patients. We utilized in vitro and in vivo models, including BMSC cultures, osteogenic differentiation assays, and an OVX-induced mouse model of OP. Molecular techniques such as quantitative RT-PCR, western blotting, and functional assays like alizarin red staining (ARS) were employed to evaluate circCOX6A1 effects on BMSC proliferation, apoptosis, and osteogenic differentiation. The interaction between circCOX6A1, miR-512-3p, and DYRK2 was investigated through dual luciferase reporter assays, RNA immunoprecipitation, and RNA pull-down assays. RESULTS: CircCOX6A1 was found to be upregulated in osteoporosis patients, and its expression inversely correlated with osteogenic differentiation of BMSCs. CircCOX6A1 knockdown enhanced osteogenic differentiation, as evidenced by increased mineralized nodule formation and upregulation of osteogenic markers. In vivo, circCOX6A1 knockdown ameliorated osteoporosis progression in OVX mice. Mechanistically, circCOX6A1 acted as a sponge for miR-512-3p, subsequently regulating DYRK2 expression. CONCLUSION: This study provides compelling evidence for the role of circCOX6A1 in osteoporosis pathogenesis. CircCOX6A1 negatively regulates BMSC osteogenic differentiation through the miR-512-3p/DYRK2 axis, suggesting its potential as a therapeutic target for mitigating OP progression.


Asunto(s)
Diferenciación Celular , Quinasas DyrK , Células Madre Mesenquimatosas , MicroARNs , Osteogénesis , Osteoporosis , Proteínas Serina-Treonina Quinasas , Proteínas Tirosina Quinasas , ARN Circular , Animales , Ratones , Apoptosis/genética , Diferenciación Celular/genética , Proliferación Celular/genética , Modelos Animales de Enfermedad , Células Madre Mesenquimatosas/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Osteogénesis/genética , Osteoporosis/genética , Osteoporosis/metabolismo , Osteoporosis/patología , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Tirosina Quinasas/genética , Proteínas Tirosina Quinasas/metabolismo , ARN Circular/genética , ARN Circular/metabolismo
13.
Cereb Cortex ; 33(12): 7506-7517, 2023 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-36879455

RESUMEN

Studies showed that the top-down control of the prefrontal cortex (PFC) on sensory/motor cortices changes during cognitive aging. Although music training has demonstrated efficacy on cognitive aging, its brain mechanism is still far from clear. Current music intervention studies have paid insufficient attention to the relationship between PFC and sensory regions. Functional gradient provides a new perspective that allows researchers to understand network spatial relationships, which helps study the mechanism of music training that affects cognitive aging. In this work, we estimated the functional gradients in four groups, young musicians, young control, older musicians, and older control. We found that cognitive aging leads to gradient compression. Compared with young subjects, older subjects presented lower and higher principal gradient scores in the right dorsal and medial prefrontal and the bilateral somatomotor regions, respectively. Meanwhile, by comparing older control and musicians, we found a mitigating effect of music training on gradient compression. Furthermore, we revealed that the connectivity transitions between prefrontal and somatomotor regions at short functional distances are a potential mechanism for music to intervene in cognitive aging. This work contributes to understanding the neuroplasticity of music training on cognitive aging.


Asunto(s)
Envejecimiento Cognitivo , Música , Corteza Sensoriomotora , Humanos , Mapeo Encefálico , Corteza Prefrontal
14.
Mol Cell ; 61(4): 625-639, 2016 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-26876939

RESUMEN

Reduction of translational fidelity often occurs in cells with high rates of protein synthesis, generating defective ribosomal products. If not removed, such aberrant proteins can be a major source of cellular stress causing human diseases. Here, we demonstrate that mTORC1 promotes the formation of immunoproteasomes for efficient turnover of defective proteins and cell survival. mTORC1 sequesters precursors of immunoproteasome ß subunits via PRAS40. When activated, mTORC1 phosphorylates PRAS40 to enhance protein synthesis and simultaneously to facilitate the assembly of the ß subunits for forming immunoproteasomes. Consequently, the PRAS40 phosphorylations play crucial roles in clearing aberrant proteins that accumulate due to mTORC1 activation. Mutations of RAS, PTEN, and TSC1, which cause mTORC1 hyperactivation, enhance immunoproteasome formation in cells and tissues. Those mutations increase cellular dependence on immunoproteasomes for stress response and survival. These results define a mechanism by which mTORC1 couples elevated protein synthesis with immunoproteasome biogenesis to protect cells against protein stress.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Complejos Multiproteicos/metabolismo , Fosfoproteínas/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Biosíntesis de Proteínas , Serina-Treonina Quinasas TOR/metabolismo , Animales , Supervivencia Celular , Células HCT116 , Células HEK293 , Humanos , Diana Mecanicista del Complejo 1 de la Rapamicina , Ratones , Mutación , Fosfohidrolasa PTEN/genética , Fosforilación , Transducción de Señal , Proteína 1 del Complejo de la Esclerosis Tuberosa , Proteínas Supresoras de Tumor/genética , Proteínas ras/genética
15.
BMC Med Educ ; 24(1): 188, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38395850

RESUMEN

BACKGROUND: The learning of Occupational Health and Occupational Medicine in undergraduate college students in China has been hindered by various factors. This study aimed to explore the effects of the application of Massive Open Online Courses (MOOC) & Problem-based learning (PBL) in the learning of Occupational Health and Occupational Medicine in undergraduate college students in China. METHODS: Students enrolled in 2017 and 2018 were categorized in the control group and study group, and received PBL learning and MOOC + PBL learning, respectively. The effects of learning were assessed by scores of final exam, satisfaction degree of students, and feedbacks. RESULTS: The mean score of the final exam was not significantly different between the two groups. However, the further comparison by levels of scores showed that the percentages of good and excellent were both significantly higher in the study group than control group. The overall satisfaction degree was significantly higher in the study group than control group. In addition, the scores of the 3 dimensions of satisfaction degree, i.e. learning preparation, learning process, and learning effect, were all significantly higher in the study group than control group. The feedbacks of the students showed that they thought MOOC + PBL learning could better improve the learning efficacy, despite a substantial proportion of students reported that MOOC + PBL learning more time-consuming. CONCLUSIONS: The findings showed that the combination of MOOC and PBL in the learning of Occupational Health and Occupational Medicine is an effective method capable of improving the learning efficacy in college students of Prophylactic Medicine. Further efforts are needed to optimize the MOOC platform to provide a friendlier interface.


Asunto(s)
Educación a Distancia , Educación de Pregrado en Medicina , Salud Laboral , Medicina del Trabajo , Estudiantes de Medicina , Humanos , Aprendizaje Basado en Problemas/métodos , Educación de Pregrado en Medicina/métodos
16.
Zhongguo Zhong Yao Za Zhi ; 49(3): 754-762, 2024 Feb.
Artículo en Zh | MEDLINE | ID: mdl-38621879

RESUMEN

This study aims to explore the mechanism of Linggui Zhugan Decoction(LGZGD) in inhibiting Angiotensin Ⅱ(AngⅡ)-induced cardiomyocyte hypertrophy by regulating sigma-1 receptor(Sig1R). The model of H9c2 cardiomyocyte hypertrophy induced by AngⅡ in vitro was established by preparing LGZGD-containing serum and blank serum. H9c2 cells were divided into normal group, AngⅡ model group, 20% normal rat serum group(20% NSC), and 20% LGZGD-containing serum group. After the cells were incubated with AngⅡ(1 µmol·L~(-1)) or AngⅡ with serum for 72 h, the surface area of cardiomyocytes was detected by phalloidine staining, and the activities of Na~+-K~+-ATPase and Ca~(2+)-Mg~(2+)-ATPase were detected by micromethod. The mitochondrial Ca~(2+) levels were detected by flow cytometry, and the expression levels of atrial natriuretic peptide(ANP), brain natriuretic peptide(BNP), Sig1R, and inositol 1,4,5-triphosphate receptor type 2(IP_3R_2) were detected by Western blot. The expression of Sig1R was down-regulated by transfecting specific siRNA for investigating the efficacy of LGZGD-containing serum on cardiomyocyte surface area, Na~+-K~+-ATPase activity, Ca~(2+)-Mg~(2+)-ATPase activity, mitochondrial Ca~(2+), as well as ANP, BNP, and IP_3R_2 protein expressions. The results showed that compared with the normal group, AngⅡ could significantly increase the surface area of cardiomyocytes and the expression of ANP and BNP(P<0.01), and it could decrease the activities of Na~+-K~+-ATPase and Ca~(2+)-Mg~(2+)-ATPase, the concentration of mitochondrial Ca~(2+), and the expression of Sig1R(P<0.01). In addition, IP_3R_2 protein expression was significantly increased(P<0.01). LGZGD-containing serum could significantly decrease the surface area of cardiomyocytes and the expression of ANP and BNP(P<0.05, P<0.01), and it could increase the activities of Na~+-K~+-ATPase and Ca~(2+)-Mg~(2+)-ATPase, the concentration of mitochondrial Ca~(2+ )(P<0.01), and the expression of Sig1R(P<0.05). In addition, IP_3R_2 protein expression was significantly decreased(P<0.05). However, after Sig1R was down-regulated, the effects of LGZGD-containing serum were reversed(P<0.01). These results indicated that the LGZGD-containing serum could inhibit cardiomyocyte hypertrophy induced by AngⅡ, and its pharmacological effect was related to regulating Sig1R, promoting mitochondrial Ca~(2+ )inflow, restoring ATP synthesis, and protecting mitochondrial function.


Asunto(s)
Miocitos Cardíacos , ATPasa Intercambiadora de Sodio-Potasio , Ratas , Animales , Células Cultivadas , ATPasa Intercambiadora de Sodio-Potasio/genética , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Factor Natriurético Atrial/genética , Factor Natriurético Atrial/metabolismo , Angiotensina II/efectos adversos , Angiotensina II/metabolismo , Péptido Natriurético Encefálico/metabolismo , Hipertrofia/metabolismo , Cardiomegalia/inducido químicamente , Cardiomegalia/tratamiento farmacológico , Cardiomegalia/genética
17.
Zhongguo Zhong Yao Za Zhi ; 49(7): 1924-1931, 2024 Apr.
Artículo en Zh | MEDLINE | ID: mdl-38812205

RESUMEN

The Chinese medical mechanism of Huanglian Jieduo Decoction on treating Alzheimer's disease(AD) characterized by "toxin damaging brain collateral" is still unclear. This study aims to explore the mechanism of Huanglian Jieduo Decoction on regulating triggering receptor expressed on myeloid cells 2(TREM2)/protein kinase B(Akt)/glycogen synthase kinase 3ß(GSK3ß) pathway to improve the cognitive deficit in APP/PS1 transgenic mice. APP/PS1 mice of approximately nine months old were randomly divided into the model group, the low, medium, and high(2.5, 5, and 10 g·kg~(-1)) groups of Huanglian Jiedu Decoction, and 0.75 mg·kg~(-1) donepezil hydrochloride group, and the C57BL/6J mice with the same age were taken as the normal group. After one month of continuous oral administration, a Morris water maze was performed to detect the learning and memory ability of mice. Hematoxylin-eosin(HE) staining was applied to observe the morphology of neuronal cells in the cortical area of mice. Immunofluorescence was used to detect the protein expressions of ß-amyloid(Aß_(1-42)), CD86, and arginase 1(Arg1). The mRNA levels of interleukin(IL)-1ß, IL-6, and IL-10 in the cortex of mice were detected by real-time fluorescence quantitative polymerase chain reaction(RT-qPCR). The protein expressions of TREM2, phosphoinositide-3 kinase(PI3K), Akt, GSK3ß, and beta-catenin(ß-catenin) in mouse cortex were determined by Western blot. The results indicated that the escape latency of the model group was significantly prolonged, and the residence time in the target quadrant and the number of crossing the platform were significantly reduced compared with the normal group. Mice in the model group had a significantly lower number of neurons in the cortex and showed nuclear pyknosis and a significant increase in the expressions of Aß_(1-42) and CD86. The mRNA levels of IL-1ß and IL-6 in tissue were significantly increased, IL-10 were increased, while Arg1 were significantly decreased. The expression of TREM2, p-PI3K(Y607), p-Akt(T308), p-GSK3ß(Ser9), and ß-catenin in the cortex were significantly down-regulated. Compared with the model group, the escape latency of the mice in the administration group was significantly shortened, and the number of crossing the platform and the residence time in the target quadrant were significantly increased. Furthermore, the number of neurons in the cortex of mice was increased, and nuclear pyknosis was improved. Aß_(1-42) deposition was decreased significantly. The mRNA levels of IL-1ß, IL-6 and CD86 were significantly decreased, while IL-10 and Arg1 levels were significantly increased. The expression of TREM2, p-PI3K(Y607), p-Akt(T308), p-GSK3ß(Ser9), and ß-catenin protein in the cortex of each administration group was significantly up-regulated compared with the model group. In conclusion, Huanglian Jiedu Decoction reduced the expression of Aß_(1-42) and neuroinflammation to a neuro-protective effect, thereby improving the learning and memory ability in APP/PS1 mice, which may be related to the TREM2/Akt/GSK3ß signaling pathway.


Asunto(s)
Enfermedad de Alzheimer , Corteza Cerebral , Medicamentos Herbarios Chinos , Glucógeno Sintasa Quinasa 3 beta , Glicoproteínas de Membrana , Ratones Endogámicos C57BL , Ratones Transgénicos , Proteínas Proto-Oncogénicas c-akt , Receptores Inmunológicos , Animales , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Glucógeno Sintasa Quinasa 3 beta/genética , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/administración & dosificación , Ratones , Corteza Cerebral/metabolismo , Corteza Cerebral/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/genética , Receptores Inmunológicos/genética , Receptores Inmunológicos/metabolismo , Glicoproteínas de Membrana/metabolismo , Glicoproteínas de Membrana/genética , Masculino , Transducción de Señal/efectos de los fármacos , Humanos
18.
Angew Chem Int Ed Engl ; : e202407923, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38738617

RESUMEN

Although catenated cages have been widely constructed due to their unique and elegant topological structures, cyclic catenanes formed by the connection of multiple catenane units have been rarely reported. Herein, based on the orthogonal metal-coordination-driven self-assembly, we prepare a series of heterometallic [2]catenanes and cyclic bis[2]catenanes, whose structures are clearly evidenced by single-crystal X-ray analysis. Owing to the multiple positively charged nature, as well as the potential synergistic effect of the Cu(I) and Pt(II) metal ions, the cyclic bis[2]catenanes display broad-spectrum antibacterial activity. This work not only provides an efficient strategy for the construction of heterometallic [2]catenanes and cyclic bis[2]catenanes but also explores their applications as superior antibacterial agents, which will promote the construction of advanced supramolecular structures for biomedical applications.

19.
J Cell Mol Med ; 27(23): 3706-3716, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37950418

RESUMEN

Excessive productions of inflammatory cytokines and free radicals are involved in spinal cord injury (SCI). Fibroblast growth factor 5 (FGF5) is associated with inflammatory response and oxidative damage, and we herein intend to determine its function in SCI. Lentivirus was instilled to overexpress or knockdown FGF5 expression in mice. Compound C or H89 2HCl were used to suppress AMP-activated protein kinase (AMPK) or protein kinase A (PKA), respectively. FGF5 level was significantly decreased during SCI. FGF5 overexpression mitigated, while FGF5 silence further facilitated inflammatory response, oxidative damage and SCI. Mechanically, FGF5 activated AMPK to attenuate SCI in a cAMP/PKA-dependent manner, while inhibiting AMPK or PKA with pharmacological methods significantly abolished the neuroprotective effects of FGF5 against SCI. More importantly, serum FGF5 level was decreased in SCI patients, and elevated serum FGF5 level often indicate better prognosis. Our study identifies FGF5 as an effective therapeutic and prognostic target for SCI.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Factor 5 de Crecimiento de Fibroblastos , Estrés Oxidativo , Traumatismos de la Médula Espinal , Animales , Humanos , Ratones , Proteínas Quinasas Activadas por AMP/metabolismo , Factor 5 de Crecimiento de Fibroblastos/genética , Factor 5 de Crecimiento de Fibroblastos/metabolismo , Médula Espinal/metabolismo , Traumatismos de la Médula Espinal/metabolismo , Ratones Noqueados , Masculino , Femenino , Adulto , Persona de Mediana Edad
20.
Small ; 19(52): e2305308, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37635096

RESUMEN

The evolution and formation process of two-dimensional metal-organic frameworks (MOFs) primarily arise from the anisotropic growth of crystals, leading to variations in photocatalytic performance. It is crucial to achieve a synergistic combination of anisotropic electron transfer direction and dimension reduction strategies. In this study, a novel approach that effectively blocks crystal growth accretion through the coordination of solvent molecules is presented, achieving the successful synthesis of impurity-free two-dimensional nanosheet Zn-PTC with exceptional hydrogen evolution reaction (HER) performance (15.4 mmol g-1  h-1 ). The structural and photophysical characterizations validate the successful prevention of crystal accretion, while establishing correlation between structural anisotropy and intrinsic charge transfer mode through transient spectroscopy. These findings unequivocally demonstrate that electron transfer along the [001] direction plays a pivotal role in the redox performance of nano-Zn-PTC. Subsequently, by coupling the photocatalytic performance and density functional theory (DFT) simulation calculations, the carrier diffusion kinetics is explored, revealing that effective dimension reduction along the ligand-to-metal charge transfer (LMCT) direction is the key to achieving superior photocatalytic performance.

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