Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 50
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Mol Cell ; 78(4): 714-724.e5, 2020 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-32353258

RESUMEN

Nonrandom DNA segregation (NDS) is a mitotic event in which sister chromatids carrying the oldest DNA strands are inherited exclusively by one of the two daughter cells. Although this phenomenon has been observed across various organisms, the mechanism and physiological relevance of this event remain poorly defined. Here, we demonstrate that DNA replication stress can trigger NDS in human cells. This biased inheritance of old template DNA is associated with the asymmetric DNA damage response (DDR), which derives at least in part from telomeric DNA. Mechanistically, we reveal that the ATR/CHK1 signaling pathway plays an essential role in mediating NDS. We show that this biased segregation process leads to cell-cycle arrest and cell death in damaged daughter cells inheriting newly replicated DNA. These data therefore identify a key role for NDS in the maintenance of genomic integrity within cancer cell populations undergoing replication stress due to oncogene activation.


Asunto(s)
Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1)/metabolismo , Cromosomas Humanos/genética , Daño del ADN , Replicación del ADN , Mitosis , Proteínas de la Ataxia Telangiectasia Mutada/genética , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1)/genética , Segregación Cromosómica , Células HeLa , Humanos , Transducción de Señal
2.
Dev Biol ; 465(2): 100-107, 2020 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-32479761

RESUMEN

The proliferation and hypertrophy of chondrocytes play important roles in endochondral ossification, which is tightly regulated during skeleton development. However, the regulation mechanism remains largely unknown. Here we show that DDB1 (Damaged DNA Binding Protein 1) has a critical function in the development of growth plates. Using chondrocyte-specific DDB1 knockout mice, we found that DDB1 deletion in chondrocytes results in dwarfism due to the aberrant skeleton development. The structure of growth plate in tibia becomes disordered at P21, not in femur. But at P70, the changes are severer in femur than tibia. Chondrocyte proliferation and differentiation are attenuated and asynchronous in both tibia and femur at P7 and P21. Furthermore, DDB1 deficiency induces p27 upregulation and subsequent cell cycle arrest in primary chondrocytes. Therefore, our data reveal that DDB1 is essential for the skeleton development by controlling chondrocyte proliferation and differentiation.


Asunto(s)
Puntos de Control del Ciclo Celular , Condrocitos/metabolismo , Proteínas de Unión al ADN/metabolismo , Fémur/crecimiento & desarrollo , Placa de Crecimiento/metabolismo , Desarrollo Musculoesquelético , Tibia/crecimiento & desarrollo , Animales , Condrocitos/patología , Proteínas de Unión al ADN/genética , Fémur/patología , Placa de Crecimiento/patología , Hipertrofia , Ratones , Ratones Noqueados , Tibia/patología
3.
Small ; 16(31): e2002537, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32519453

RESUMEN

Triple-negative breast cancer (TNBC) is highly aggressive and insensitive to conventional targeted therapies, resulting in poor therapeutic outcomes. Recent studies have shown that abnormal iron metabolism is observed in TNBC, suggesting an opportunity for TNBC treatment via the iron-dependent Fenton reaction. Nevertheless, the efficiency of current Fenton reagents is largely restricted by the lack of specificity and low intracellular H2 O2 level of cancer cells. Herein, core-shell-satellite nanomaces (Au @ MSN@IONP) are fabricated, as near-infrared (NIR) light-triggered self-fueling Fenton reagents for the amplified Fenton reaction inside TNBC cells. Specifically, the Au nanorod core can convert NIR light energy into heat to induce massive production of intracellular H2 O2 , thereby the surface-decorated iron oxide nanoparticles (IONP) are being fueled for robust Fenton reaction. By exploiting the vulnerability of iron efflux in TNBC cells, such a self-fueling Fenton reaction leads to highly specific anti-TNBC efficacy with minimal cytotoxicity to normal cells. The PI3K/Akt/FoxO axis, intimately involved in the redox regulation and survival of TNBC, is demonstrated to be inhibited after the treatment. Consequently, precise in vivo orthotopic TNBC ablation is achieved under the guidance of IONP-enhanced magnetic resonance imaging. The results demonstrate the proof-of-concept of NIR-light-triggered self-fueling Fenton reagents against TNBC with low ferroportin levels.


Asunto(s)
Neoplasias de la Mama Triple Negativas , Línea Celular Tumoral , Humanos , Peróxido de Hidrógeno , Hierro , Fosfatidilinositol 3-Quinasas , Neoplasias de la Mama Triple Negativas/terapia
4.
EMBO Rep ; 19(9)2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30108055

RESUMEN

Timely and faithful duplication of the entire genome depends on completion of replication. Replication forks frequently encounter obstacles that may cause genotoxic fork stalling. Nevertheless, failure to complete replication rarely occurs under normal conditions, which is attributed to an intricate network of proteins that serves to stabilize, repair and restart stalled forks. Indeed, many of the components in this network are encoded by tumour suppressor genes, and their loss of function by mutation or deletion generates genomic instability, a hallmark of cancer. Paradoxically, the same fork-protective network also confers resistance of cancer cells to chemotherapeutic drugs that induce high-level replication stress. Here, we review the mechanisms and major pathways rescuing stalled replication forks, with a focus on fork stabilization preventing fork collapse. A coherent understanding of how cells protect their replication forks will not only provide insight into how cells maintain genome stability, but also unravel potential therapeutic targets for cancers refractory to conventional chemotherapies.


Asunto(s)
Replicación del ADN , Inestabilidad Genómica/fisiología , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Genes BRCA2/fisiología , Humanos , Redes y Vías Metabólicas , Modelos Teóricos , Terapia Molecular Dirigida , Mutación , Poli(ADP-Ribosa) Polimerasa-1/metabolismo , RecQ Helicasas/metabolismo
5.
J Biol Chem ; 291(1): 382-92, 2016 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-26555259

RESUMEN

TGF-ß is a pleiotropic cytokine that regulates a wide range of cellular actions and pathophysiological processes. TGF-ß signaling is spatiotemporally fine-tuned. As a key negative regulator of TGF-ß signaling, Smad7 exerts its inhibitory effects by blocking receptor activity, inducing receptor degradation or interfering with Smad-DNA binding. However, the functions and the molecular mechanisms underlying the actions of Smad7 in TGF-ß signaling are still not fully understood. In this study we report a novel mechanism whereby Smad7 antagonizes TGF-ß signaling at the Smad level. Smad7 oligomerized with R-Smad proteins upon TGF-ß signaling and directly inhibited R-Smad activity, as assessed by Gal4-luciferase reporter assays. Mechanistically, Smad7 competes with Smad4 to associate with R-Smads and recruits the E3 ubiquitin ligase NEDD4L to activated R-Smads, leading to their polyubiquitination and proteasomal degradation. Similar to the R-Smad-Smad4 oligomerization, the interaction between R-Smads and Smad7 is mediated by their mad homology 2 (MH2) domains. A positive-charged basic region including the L3/ß8 loop-strand module and adjacent amino acids in the MH2 domain of Smad7 is essential for the interaction. These results shed new light on the regulation of TGF-ß signaling by Smad7.


Asunto(s)
Transducción de Señal , Proteínas Smad Reguladas por Receptores/metabolismo , Proteína smad7/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Aminoácidos/metabolismo , Animales , Complejos de Clasificación Endosomal Requeridos para el Transporte/metabolismo , Células HEK293 , Humanos , Visón , Ubiquitina-Proteína Ligasas Nedd4 , Poliubiquitina/metabolismo , Unión Proteica/efectos de los fármacos , Dominios y Motivos de Interacción de Proteínas , Proteolisis , Proteína smad3/química , Proteína smad3/metabolismo , Proteína Smad4/metabolismo , Proteína smad7/química , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación
6.
Front Microbiol ; 14: 1183415, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37405166

RESUMEN

Periodontitis is an inflammatory disease initiated by periodontopathogenic bacteria in the dental plaque biofilms. Understanding the role of Porphyromonas gingivalis (P. gingivalis), a keystone pathogen associated with chronic periodontitis, in the inflammatory response is crucial. Herein, we investigated whether P. gingivalis infection triggers the expression of the type I IFN gene and various cytokines and leads to activation of the cGAMP synthase-stimulator of IFN genes (cGAS-STING) pathway both in vitro and in a mouse model. Additionally, in an experimental model of periodontitis using P. gingivalis, StingGt mice showed lower levels of inflammatory cytokines and bone resorption than wild-type mice. Furthermore, we report that a STING inhibitor (SN-011) significantly decreased inflammatory cytokine production and osteoclast formation in a periodontitis mouse model with P. gingivalis. In addition, STING agonist (SR-717) -treated periodontitis mice displayed enhanced macrophage infiltration and M1 macrophage polarization in periodontal lesions compared with that in vehicle-treated periodontitis mice. In conclusion, our results demonstrate that the cGAS-STING signaling pathway may be one of the key mechanisms crucial for the P. gingivalis-induced inflammatory response that leads to chronic periodontitis.

7.
ACS Nano ; 17(18): 18548-18561, 2023 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-37706454

RESUMEN

Replication stress (RS) induced by DNA damage plays a significant role in conferring the anticancer effects of radiotherapy and is tightly associated with radioresistance of cancer cells. Amplification of RS represents an effective approach to improving the efficacy of radiotherapy, although the development of selective RS amplifiers remains an unexplored frontier. We herein present an RS nano amplifier (RSNA) consisting of a catalytic FePt nanoparticle loaded with the chemotherapeutic doxorubicin (DOX), which selectively exacerbates RS in cancer cells by promoting replication fork (RF) catastrophe. RSNA converts the excessive reactive oxygen species (ROS) in cancer cells into oxygen, enhancing the DNA-damaging effects of radiotherapy to create more template lesions that impede RF progression in coalition with DOX. After radiation, ROS scavenging by RSNA accelerates RF progression through damaged template strands, increasing the frequency of RF collapse into double-strand breaks. Moreover, pretreatment with RSNA accumulates cancer cells in the S phase, exposing more RFs to radiation-induced RS. These effects of RSNA convergently maximize RS in cancer cells, effectively overcoming the radioresistance of cancer cells without affecting normal cells. Our study demonstrates the feasibility of selectively amplifying RS to boost radiotherapy.


Asunto(s)
Neoplasias , Humanos , Especies Reactivas de Oxígeno , División Celular , Neoplasias/tratamiento farmacológico , Neoplasias/radioterapia , Catálisis , Daño del ADN , Doxorrubicina/farmacología
8.
Huan Jing Ke Xue ; 44(11): 6085-6094, 2023 Nov 08.
Artículo en Zh | MEDLINE | ID: mdl-37973092

RESUMEN

Water quality is one of the most important environmental issues in the sustainable development of karst areas. To investigate heavy metal pollution and assess health risk in karst water basins around mines, 18 groups of water samples were collected from the river and groundwater in the Sidi River karst basin, and the concentrations of nine types of heavy metals(Cu, Pb, Zn, Cd, Mn, Fe, As, Cr, and Sr) were determined. Sample data were analyzed using principal component analysis, correlation analysis, water quality index, the Nemerow comprehensive pollution index, hazard quotient, and hazard index. The results showed that the Sidi River was slightly alkaline. The farther the river water samples were from the tailings reservoir, the lower were the concentrations of Cu, Pb, Zn, Cd, Mn, Fe, As, and Sr in the river water. Principal component and correlation analyses showed that heavy metals in the Sidi River karst basin mainly came from mine discharge(55.42%), carbonate weathering dissolution(21.41%), and human activities(14.72%). Eighty-two percent of the samples in the river and all the samples in the groundwater were excellent water. The Nemerow comprehensive pollution index in the river was 4.12 with strong pollution. All the hazard indices were below 1, and Pb, Zn, As, Cd, and Cr were potentially threatening metals in the Sidi River karst basin. The concentration of heavy metals changed significantly after entering the karst conduit, indicating that the unique properties of the karst aquifer affected the spatial variation of the heavy metal concentration. The results of this study can provide data reference for water resource prevention and human health protection in the Sidi River karst basin and similar karst basins.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Humanos , Zinc , Plomo/análisis , Monitoreo del Ambiente , Cadmio/análisis , Metales Pesados/análisis , Calidad del Agua , Ríos , Medición de Riesgo , Contaminantes Químicos del Agua/análisis , China
9.
Zhongguo Gu Shang ; 35(11): 1060-4, 2022 Nov 25.
Artículo en Zh | MEDLINE | ID: mdl-36415192

RESUMEN

OBJECTIVE: To investigate the relationship between serum C1q/tumor necrosis factor-related protein-3(CTRP3) and peroxisome proliferator-activated receptor γ coactivator-1α(PGC-1α) on predictive value of expression level on fracture healing. METHODS: From January 2019 to January 2020, 80 patients with traumatic tibial plateau fractures were treated by internal fixation with support plates through the posterior approach of the knee joint. The patients were followed up for 12 months. According to the criteria for delayed fracture healing, the patients were divided into two groups:54 patients in fracture healing group included 24 males and 30 females, aged 29 to 75 years old with an average of (52.36±13.17) years;In the delayed healing group, there were 26 cases, 13 males and 13 females, aged from 29 to 75 with an average od (53.82±13.52) years. The serum levels of CTRP3, PGC-1αand 25 hydroxyvitamin D3[25(OH)D3] in patients with traumatic fracture were detected by enzyme-linked immunosorbent assay(ELISA);Blood phosphorus and calcium levels were measured by automatic biochemical analyzer, and the product of calcium and phosphorus was calculated;Pearson's method was used to analyze the correlation between serum CTRP3, PGC-1αand bone biochemical indexes in patients with delayed union one week after operation;The predictive value of serum levels of CTRP3 and PGC-1αon traumatic fracture healing was analyzed by receiver operating characteristic curve(ROC curve). RESULTS: PGC-1α, calcium phosphorus product and 25(OH)D3 in the fracture healing group were higher than those in the delayed healing group at 1 and 4 weeks after operation(P<0.05). Serum CTRP3 was positively correlated with PGC-1α(r=0.637, P<0.05) and positively correlated with calcium phosphorus product and 25(OH)D3(P<0.05). The areas under the curve(AUC) of serum ctrp3 and PGC-1α levels in predicting traumatic fracture healing were 0.845 and 0.855, respectively. The cutoff values were 188.678 pg/ml and 2.697 ng/ml, respectively. The specificity was 96.2% and 80.8%, and the sensitivity was 53.7% and 77.8%;The predicted AUC was 0.904, the specificity was 88.5%, and the sensitivity was 81.5%. CONCLUSION: The serum levels of CTRP3 and PGC-1 in patients with delayed union of traumatic fracture at 1 and 4 weeks after operation α The expression level is of certain reference value to predict the fracture healing status of patients.


Asunto(s)
Curación de Fractura , Fracturas de la Tibia , Masculino , Humanos , Adulto , Persona de Mediana Edad , Anciano , Calcio , Fracturas de la Tibia/cirugía , Huesos , Fósforo
10.
Front Psychol ; 13: 913672, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36092033

RESUMEN

How to improve the development quality of state-owned enterprises is of great significance to the economic and social development in the transition period. And promoting the reform of mixed ownership is an important path for state-owned enterprises to achieve high-quality development. Based on the micro-data of China's A-share listed state-owned companies, the paper explores the impact of mixed ownership reform on the high-quality development of state-owned enterprises. It clarifies the importance and moderation of equity reform and the heterogeneity of impact effects from the theoretical mechanism analysis and empirical test. It also analyzes the reasons of inverted U-shape from the perspective of the transmission mechanism of the internal competition atmosphere and non-state-owned capital speculation motivation. It is found that the relationship between equity reform and state-owned enterprises' high-quality development is inverted U-shaped with multi-dimensional heterogeneity. From the analysis of conduction mechanism, on the one hand, the equity reform can enhance the internal competitive atmosphere, stimulate the vitality of enterprises and improve the development quality for state-owned enterprises. On the other hand, it enhances the speculation motivation of enterprises and slows down the high-quality development process.

11.
Front Genet ; 13: 906957, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35669181

RESUMEN

Common fragile sites (CFSs) are specific genomic loci prone to forming gaps or breakages upon replication perturbation, which correlate well with chromosomal rearrangement and copy number variation. CFSs have been actively studied due to their important pathophysiological relevance in different diseases such as cancer and neurological disorders. The genetic locations and sequences of CFSs are crucial to understanding the origin of such unstable sites, which require reliable mapping and characterizing approaches. In this review, we will inspect the evolving techniques for CFSs mapping, especially genome-wide mapping and sequencing of CFSs based on current knowledge of CFSs. We will also revisit the well-established hypotheses on the origin of CFSs fragility, incorporating novel findings from the comprehensive analysis of finely mapped CFSs regarding their locations, sequences, and replication/transcription, etc. This review will present the most up-to-date picture of CFSs and, potentially, a new framework for future research of CFSs.

12.
Nanomicro Lett ; 14(1): 101, 2022 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-35412159

RESUMEN

The structural change-mediated catalytic activity regulation plays a significant role in the biological functions of natural enzymes. However, there is virtually no artificial nanozyme reported that can achieve natural enzyme-like stringent spatiotemporal structure-based catalytic activity regulation. Here, we report a sub-nanostructural transformable gold@ceria (STGC-PEG) nanozyme that performs tunable catalytic activities via near-infrared (NIR) light-mediated sub-nanostructural transformation. The gold core in STGC-PEG can generate energetic hot electrons upon NIR irradiation, wherein an internal sub-nanostructural transformation is initiated by the conversion between CeO2 and electron-rich state of CeO2-x, and active oxygen vacancies generation via the hot-electron injection. Interestingly, the sub-nanostructural transformation of STGC-PEG enhances peroxidase-like activity and unprecedentedly activates plasmon-promoted oxidase-like activity, allowing highly efficient low-power NIR light (50 mW cm-2)-activated photocatalytic therapy of tumors. Our atomic-level design and fabrication provide a platform to precisely regulate the catalytic activities of nanozymes via a light-mediated sub-nanostructural transformation, approaching natural enzyme-like activity control in complex living systems.

13.
Artículo en Inglés | MEDLINE | ID: mdl-36361169

RESUMEN

Karst water quality is one of the most important environmental issues in karst areas. The study's purpose was to investigate dissolved heavy metal pollution and health risk assessment in karst water basins around mines. River water and groundwater samples were analyzed by principal component analysis, correlation analysis, water quality index, hazard quotient, and hazard index. Median concentrations of dissolved heavy metals in the Sidi River were similar to the world average with a slightly alkaline characteristic. The concentrations of most dissolved heavy metals in river water were higher than those in groundwater. The concentrations of Zn, Pb, and Cd around the mine exceeded the limits of drinking water indicators. The poor water quality samples with high water quality index values were distributed around the mine. Lead (Pb), Zn, As, Cd, and Cr were potentially threatening metals in the study area. The pollution level of dissolved heavy metals in the Sidi River was at a medium level compared with other rivers worldwide. Principal component analysis and correlation analysis showed that Cu, Pb, Zn, Cd, Mn, Fe, As, and Sr mainly came from mine drainage; Ca2+, Mg2+, and Cr mainly came from the contribution of carbonate rocks; Na+ and K+ were related to local human agricultural activities. The concentrations of dissolved heavy metals in groundwater were affected by karst aquifers. The results of this study can provide a data reference for water resources prevention and human health protection in the Sidi River's karst basin and similar karst basins.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Humanos , Monitoreo del Ambiente/métodos , Cadmio/análisis , Plomo/análisis , Contaminantes Químicos del Agua/análisis , Metales Pesados/análisis , Ríos , Calidad del Agua , Medición de Riesgo , China
14.
Exploration (Beijing) ; 2(1): 20210086, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37324577

RESUMEN

Nanozymes are nanomaterials with similar catalytic activities to natural enzymes. Compared with natural enzymes, they have numerous advantages, including higher physiochemical stability, versatility, and suitability for mass production. In the past decade, the synthesis of nanozymes and their catalytic mechanisms have advanced beyond the simple replacement of natural enzymes, allowing for fascinating applications in various fields such as biosensing and disease treatment. In particular, the exploration of nanozymes as powerful toolkits in diagnostic viral testing and antiviral therapy has attracted growing attention. It can address the great challenges faced by current natural enzyme-based viral testing technologies, such as high cost and storage difficulties. Therefore, nanozyme can provide a novel nanozyme-based antiviral therapeutic regime with broader availability and generalizability that are keys to fighting a pandemic such as COVID-19. Herein, we provide a timely review of the state-of-the-art nanozymes regarding their catalytic activities, as well as a focused discussion on recent research into the use of nanozymes in viral testing and therapy. The remaining challenges and future perspectives will also be outlined. Ultimately, this review will inform readers of the current knowledge of nanozymes and inspire more innovative studies to push forward the frontier of this field.

15.
Natl Sci Rev ; 9(7): nwac080, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35832777

RESUMEN

Although molecular imaging probes have the potential to non-invasively diagnose a tumor, imaging probes that can detect a tumor and simultaneously identify tumor malignancy remain elusive. Here, we demonstrate a potassium ion (K+) sensitive dual-mode nanoprobe (KDMN) for non-invasive tumor imaging and malignancy identification, which operates via a cascaded 'AND' logic gate controlled by inputs of magnetic resonance imaging (MRI) and fluorescence imaging (FI) signals. We encapsulate commercial K+ indicators into the hollow cavities of magnetic mesoporous silica nanoparticles, which are subsequently coated with a K+-selective membrane that exclusively permits the passage of K+ while excluding other cations. The KDMN can readily accumulate in tumors and enhance the MRI contrast after systemic administration. Spatial information of the tumor lesion is thus accessible via MRI and forms the first layer of the 'AND' gate. Meanwhile, the KDMN selectively captures K+ and prevents interference from other cations, triggering a K+-activated FI signal as the second layer of the 'AND' gate in the case of a malignant tumor with a high extracellular K+ level. This dual-mode imaging approach effectively eliminates false positive or negative diagnostic results and allows for non-invasive imaging of tumor malignancy with high sensitivity and accuracy.

16.
Nat Commun ; 12(1): 3840, 2021 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-34158498

RESUMEN

Histopathological level imaging in a non-invasive manner is important for clinical diagnosis, which has been a tremendous challenge for current imaging modalities. Recent development of ultra-high-field (UHF) magnetic resonance imaging (MRI) represents a large step toward this goal. Nevertheless, there is a lack of proper contrast agents that can provide superior imaging sensitivity at UHF for disease detection, because conventional contrast agents generally induce T2 decaying effects that are too strong and thus limit the imaging performance. Herein, by rationally engineering the size, spin alignment, and magnetic moment of the nanoparticles, we develop an UHF MRI-tailored ultra-sensitive antiferromagnetic nanoparticle probe (AFNP), which possesses exceptionally small magnetisation to minimize T2 decaying effect. Under the applied magnetic field of 9 T with mice dedicated hardware, the nanoprobe exhibits the ultralow r2/r1 value (~1.93), enabling the sensitive detection of microscopic primary tumours (<0.60 mm) and micrometastases (down to 0.20 mm) in mice. The sensitivity and accuracy of AFNP-enhanced UHF MRI are comparable to those of the histopathological examination, enabling the development of non-invasive visualization of previously undetectable biological entities critical to medical diagnosis and therapy.


Asunto(s)
Medios de Contraste/química , Imagen por Resonancia Magnética/métodos , Magnetismo , Nanopartículas/química , Neoplasias/diagnóstico por imagen , Animales , Línea Celular Tumoral , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Microscopía Electrónica de Transmisión , Nanopartículas/ultraestructura , Neoplasias/patología , Células RAW 264.7 , Ratas Wistar , Trasplante Heterólogo
17.
Adv Sci (Weinh) ; 8(8): 2004115, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33898190

RESUMEN

Allergic diseases are pathological immune responses with significant morbidity, which are closely associated with allergic mediators as released by allergen-stimulated mast cells (MCs). Prophylactic stabilization of MCs is regarded as a practical approach to prevent allergic diseases. However, most of the existing small molecular MC stabilizers exhibit a narrow therapeutic time window, failing to provide long-term prevention of allergic diseases. Herein, ceria nanoparticle (CeNP-) based phosphatase-mimetic nano-stabilizers (PMNSs) with a long-term therapeutic time window are developed for allergic disease prevention. By virtue of the regenerable catalytic hotspots of oxygen vacancies on the surface of CeNPs, PMNSs exhibit sustainable phosphatase-mimetic activity to dephosphorylate phosphoproteins in allergen-stimulated MCs. Consequently, PMNSs constantly modulate intracellular phospho-signaling cascades of MCs to inhibit the degranulation of allergic mediators, which prevents the initiation of allergic mediator-associated pathological responses, eventually providing protection against allergic diseases with a long-term therapeutic time window.


Asunto(s)
Alérgenos/inmunología , Degranulación de la Célula/inmunología , Hipersensibilidad/inmunología , Monoéster Fosfórico Hidrolasas/inmunología , Animales , Biomimética , Modelos Animales de Enfermedad , Mastocitos , Ratones
18.
ACS Nano ; 15(3): 5263-5275, 2021 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-33683854

RESUMEN

The hyperphosphorylated and aggregated tau accumulation represents a significant pathological hallmark of tauopathies including Alzheimer's disease (AD), which is highly associated with defective autophagy in neuronal cells. Autophagy-activating strategies demonstrate the therapeutic potential for AD in many studies; however, further development is limited by their low efficacy and serious side effects that result from a lack of selectivity for diseased cells. Herein, we report a tauopathy-homing nanoassembly (THN) with autophagy-activating capacity for AD treatment. Specifically, the THN can bind to hyperphosphorylated and/or aggregated tau and selectively accumulate in cells undergoing tauopathy. The THN further promotes the clearance of pathogenic tau accumulation by stimulating autophagic flux, consequently rescuing neuron viability and cognitive functions in AD rats. This study presents a promising nanotechnology-based strategy for tauopathy-homing and autophagy-mediated specific removal of pathogenic tau in AD.


Asunto(s)
Enfermedad de Alzheimer , Tauopatías , Enfermedad de Alzheimer/tratamiento farmacológico , Animales , Autofagia , Neuronas , Ratas , Tauopatías/tratamiento farmacológico , Proteínas tau
19.
Nat Commun ; 12(1): 1436, 2021 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-33664241

RESUMEN

Acute kidney injury (AKI) is a prevalent and lethal adverse event that severely affects cancer patients receiving chemotherapy. It is correlated with the collateral damage to renal cells caused by reactive oxygen species (ROS). Currently, ROS management is a practical strategy that can reduce the risk of chemotherapy-related AKI, but at the cost of chemotherapeutic efficacy. Herein, we report catalytic activity tunable ceria nanoparticles (CNPs) that can prevent chemotherapy-induced AKI without interference with chemotherapeutic agents. Specifically, in the renal cortex, CNPs exhibit catalytic activity that decomposes hydrogen peroxide, and subsequently regulate the ROS-involved genes by activating the Nrf2/Keap1 signaling pathway. These restore the redox homeostasis for the protection of kidney tubules. Under an acidic tumor microenvironment, CNPs become inert due to the excessive H+ that disrupts the re-exposure of active catalytic sites, allowing a buildup of chemotherapy-mediated ROS generation to kill cancer cells. As ROS-modulating agents, CNPs incorporated with context-dependent catalytic activity, hold a great potential for clinical prevention and treatment of AKI in cancer patients.


Asunto(s)
Lesión Renal Aguda/prevención & control , Antineoplásicos/efectos adversos , Cerio/farmacología , Túbulos Renales/patología , Especies Reactivas de Oxígeno/metabolismo , Células A549 , Animales , Antineoplásicos/uso terapéutico , Dominio Catalítico , Línea Celular Tumoral , Cerio/química , Femenino , Células Hep G2 , Humanos , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Nanopartículas/química , Neoplasias/tratamiento farmacológico , Oxidación-Reducción , Estrés Oxidativo/efectos de los fármacos , Interferencia de ARN , ARN Interferente Pequeño/genética , Transducción de Señal/efectos de los fármacos , Microambiente Tumoral
20.
Nat Commun ; 12(1): 2346, 2021 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-33879767

RESUMEN

Cancer expression of PD-L1 suppresses anti-tumor immunity. PD-L1 has emerged as a remarkable therapeutic target. However, the regulation of PD-L1 degradation is not understood. Here, we identify several compounds as inducers of PD-L1 degradation using a high-throughput drug screen. We find EGFR inhibitors promote PD-L1 ubiquitination and proteasomal degradation following GSK3α-mediated phosphorylation of Ser279/Ser283. We identify ARIH1 as the E3 ubiquitin ligase responsible for targeting PD-L1 to degradation. Overexpression of ARIH1 suppresses tumor growth and promotes cytotoxic T cell activation in wild-type, but not in immunocompromised mice, highlighting the role of ARIH1 in anti-tumor immunity. Moreover, combining EGFR inhibitor ES-072 with anti-CTLA4 immunotherapy results in an additive effect on both tumor growth and cytotoxic T cell activation. Our results delineate a mechanism of PD-L1 degradation and cancer escape from immunity via EGFR-GSK3α-ARIH1 signaling and suggest GSK3α and ARIH1 might be potential drug targets to boost anti-tumor immunity and enhance immunotherapies.


Asunto(s)
Antígeno B7-H1/metabolismo , Neoplasias/inmunología , Neoplasias/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Animales , Antígeno B7-H1/química , Antígeno CTLA-4/antagonistas & inhibidores , Ensayos de Selección de Medicamentos Antitumorales , Receptores ErbB/antagonistas & inhibidores , Femenino , Glucógeno Sintasa Quinasa 3/metabolismo , Células HEK293 , Ensayos Analíticos de Alto Rendimiento , Humanos , Inmunoterapia/métodos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Modelos Biológicos , Neoplasias/terapia , Fosforilación , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteolisis , Transducción de Señal , Linfocitos T Citotóxicos/efectos de los fármacos , Linfocitos T Citotóxicos/inmunología , Escape del Tumor/fisiología , Células U937 , Ubiquitinación/efectos de los fármacos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA