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1.
Cell ; 184(13): 3502-3518.e33, 2021 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-34048700

RESUMEN

Thermogenic adipocytes possess a therapeutically appealing, energy-expending capacity, which is canonically cold-induced by ligand-dependent activation of ß-adrenergic G protein-coupled receptors (GPCRs). Here, we uncover an alternate paradigm of GPCR-mediated adipose thermogenesis through the constitutively active receptor, GPR3. We show that the N terminus of GPR3 confers intrinsic signaling activity, resulting in continuous Gs-coupling and cAMP production without an exogenous ligand. Thus, transcriptional induction of Gpr3 represents the regulatory parallel to ligand-binding of conventional GPCRs. Consequently, increasing Gpr3 expression in thermogenic adipocytes is alone sufficient to drive energy expenditure and counteract metabolic disease in mice. Gpr3 transcription is cold-stimulated by a lipolytic signal, and dietary fat potentiates GPR3-dependent thermogenesis to amplify the response to caloric excess. Moreover, we find GPR3 to be an essential, adrenergic-independent regulator of human brown adipocytes. Taken together, our findings reveal a noncanonical mechanism of GPCR control and thermogenic activation through the lipolysis-induced expression of constitutively active GPR3.


Asunto(s)
Tejido Adiposo Pardo/metabolismo , Receptor de Androstano Constitutivo/metabolismo , Lipólisis , Receptores Acoplados a Proteínas G/metabolismo , Termogénesis , Adipocitos/metabolismo , Animales , Células COS , Células Cultivadas , Chlorocebus aethiops , Frío , Grasas de la Dieta/farmacología , Humanos , Ratones Endogámicos C57BL , Fenotipo , Receptores Acoplados a Proteínas G/genética , Transducción de Señal , Sistema Nervioso Simpático/metabolismo , Transcripción Genética
2.
Nature ; 616(7955): 77-83, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37020008

RESUMEN

Inorganic superionic conductors possess high ionic conductivity and excellent thermal stability but their poor interfacial compatibility with lithium metal electrodes precludes application in all-solid-state lithium metal batteries1,2. Here we report a LaCl3-based lithium superionic conductor possessing excellent interfacial compatibility with lithium metal electrodes. In contrast to a Li3MCl6 (M = Y, In, Sc and Ho) electrolyte lattice3-6, the UCl3-type LaCl3 lattice has large, one-dimensional channels for rapid Li+ conduction, interconnected by La vacancies via Ta doping and resulting in a three-dimensional Li+ migration network. The optimized Li0.388Ta0.238La0.475Cl3 electrolyte exhibits Li+ conductivity of 3.02 mS cm-1 at 30 °C and a low activation energy of 0.197 eV. It also generates a gradient interfacial passivation layer to stabilize the Li metal electrode for long-term cycling of a Li-Li symmetric cell (1 mAh cm-2) for more than 5,000 h. When directly coupled with an uncoated LiNi0.5Co0.2Mn0.3O2 cathode and bare Li metal anode, the Li0.388Ta0.238La0.475Cl3 electrolyte enables a solid battery to run for more than 100 cycles with a cutoff voltage of 4.35 V and areal capacity of more than 1 mAh cm-2. We also demonstrate rapid Li+ conduction in lanthanide metal chlorides (LnCl3; Ln = La, Ce, Nd, Sm and Gd), suggesting that the LnCl3 solid electrolyte system could provide further developments in conductivity and utility.

3.
Mol Cell ; 73(1): 22-35.e6, 2019 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-30527665

RESUMEN

Aberrant expression of programmed death ligand-1 (PD-L1) in tumor cells promotes cancer progression by suppressing cancer immunity. The retinoblastoma protein RB is a tumor suppressor known to regulate the cell cycle, DNA damage response, and differentiation. Here, we demonstrate that RB interacts with nuclear factor κB (NF-κB) protein p65 and that their interaction is primarily dependent on CDK4/6-mediated serine-249/threonine-252 (S249/T252) phosphorylation of RB. RNA-seq analysis shows a subset of NF-κB pathway genes including PD-L1 are selectively upregulated by RB knockdown or CDK4/6 inhibitor. S249/T252-phosphorylated RB inversely correlates with PD-L1 expression in patient samples. Expression of a RB-derived S249/T252 phosphorylation-mimetic peptide suppresses radiotherapy-induced upregulation of PD-L1 and augments therapeutic efficacy of radiation in vivo. Our findings reveal a previously unrecognized tumor suppressor function of hyperphosphorylated RB in suppressing NF-κB activity and PD-L1 expression and suggest that the RB-NF-κB axis can be exploited to overcome cancer immune evasion triggered by conventional or targeted therapies.


Asunto(s)
Antígeno B7-H1/metabolismo , Neoplasias de la Próstata/metabolismo , Proteína de Retinoblastoma/metabolismo , Factor de Transcripción ReIA/metabolismo , Escape del Tumor , Animales , Antineoplásicos Inmunológicos/farmacología , Antígeno B7-H1/antagonistas & inhibidores , Antígeno B7-H1/genética , Antígeno B7-H1/inmunología , Quimioradioterapia/métodos , Quinasa 4 Dependiente de la Ciclina/metabolismo , Quinasa 6 Dependiente de la Ciclina/metabolismo , Regulación Neoplásica de la Expresión Génica , Células HEK293 , Humanos , Masculino , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Ratones Noqueados , Ratones SCID , Células PC-3 , Fosforilación , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/inmunología , Neoplasias de la Próstata/terapia , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Tolerancia a Radiación , Proteína de Retinoblastoma/genética , Proteína de Retinoblastoma/inmunología , Transducción de Señal , Factor de Transcripción ReIA/genética , Factor de Transcripción ReIA/inmunología , Ensayos Antitumor por Modelo de Xenoinjerto
4.
Proc Natl Acad Sci U S A ; 121(35): e2408183121, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39172778

RESUMEN

The conversion of CO2 into liquid fuels, using only sunlight and water, offers a promising path to carbon neutrality. An outstanding challenge is to achieve high efficiency and product selectivity. Here, we introduce a wireless photocatalytic architecture for conversion of CO2 and water into methanol and oxygen. The catalytic material consists of semiconducting nanowires decorated with core-shell nanoparticles, with a copper-rhodium core and a chromium oxide shell. The Rh/CrOOH interface provides a unidirectional channel for proton reduction, enabling hydrogen spillover at the core-shell interface. The vectorial transfer of protons, electrons, and hydrogen atoms allows for switching the mechanism of CO2 reduction from a proton-coupled electron transfer pathway in aqueous solution to hydrogenation of CO2 with a solar-to-methanol efficiency of 0.22%. The reported findings demonstrate a highly efficient, stable, and scalable wireless system for synthesis of methanol from CO2 that could provide a viable path toward carbon neutrality and environmental sustainability.

5.
Mol Cell ; 71(4): 592-605.e4, 2018 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-30057199

RESUMEN

The bromodomain and extra-terminal domain (BET) protein BRD4 is emerging as a promising anticancer therapeutic target. However, resistance to BET inhibitors often occurs, and it has been linked to aberrant degradation of BRD4 protein in cancer. Here, we demonstrate that the deubiquitinase DUB3 binds to BRD4 and promotes its deubiquitination and stabilization. Expression of DUB3 is transcriptionally repressed by the NCOR2-HDAC10 complex. The NCOR2 gene is frequently deleted in castration-resistant prostate cancer patient specimens, and loss of NCOR2 induces elevation of DUB3 and BRD4 proteins in cancer cells. DUB3-proficient prostate cancer cells are resistant to the BET inhibitor JQ1 in vitro and in mice, but this effect is diminished by DUB3 inhibitory agents such as CDK4/6 inhibitor in a RB-independent manner. Our findings identify a previously unrecognized mechanism causing BRD4 upregulation and drug resistance, suggesting that DUB3 is a viable therapeutic target to overcome BET inhibitor resistance in cancer.


Asunto(s)
Quinasa 4 Dependiente de la Ciclina/genética , Quinasa 6 Dependiente de la Ciclina/genética , Endopeptidasas/genética , Regulación Neoplásica de la Expresión Génica , Proteínas Nucleares/genética , Neoplasias de la Próstata Resistentes a la Castración/genética , Factores de Transcripción/genética , Animales , Antineoplásicos/farmacología , Azepinas/farmacología , Proteínas de Ciclo Celular , Línea Celular Tumoral , Quinasa 4 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 4 Dependiente de la Ciclina/metabolismo , Quinasa 6 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 6 Dependiente de la Ciclina/metabolismo , Progresión de la Enfermedad , Resistencia a Antineoplásicos/genética , Endopeptidasas/metabolismo , Histona Desacetilasas/genética , Histona Desacetilasas/metabolismo , Humanos , Masculino , Ratones , Proteínas Nucleares/antagonistas & inhibidores , Proteínas Nucleares/metabolismo , Co-Represor 2 de Receptor Nuclear/deficiencia , Co-Represor 2 de Receptor Nuclear/genética , Piperazinas/farmacología , Próstata/efectos de los fármacos , Próstata/enzimología , Próstata/patología , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/enzimología , Neoplasias de la Próstata Resistentes a la Castración/patología , Inhibidores de Proteínas Quinasas/farmacología , Proteolisis , Piridinas/farmacología , Transducción de Señal , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/metabolismo , Transcripción Genética , Triazoles/farmacología , Ensayos Antitumor por Modelo de Xenoinjerto
6.
Proc Natl Acad Sci U S A ; 120(14): e2220102120, 2023 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-36996103

RESUMEN

Molecular clocks in the periphery coordinate tissue-specific daily biorhythms by integrating input from the hypothalamic master clock and intracellular metabolic signals. One such key metabolic signal is the cellular concentration of NAD+, which oscillates along with its biosynthetic enzyme, nicotinamide phosphoribosyltransferase (NAMPT). NAD+ levels feed back into the clock to influence rhythmicity of biological functions, yet whether this metabolic fine-tuning occurs ubiquitously across cell types and is a core clock feature is unknown. Here, we show that NAMPT-dependent control over the molecular clock varies substantially between tissues. Brown adipose tissue (BAT) requires NAMPT to sustain the amplitude of the core clock, whereas rhythmicity in white adipose tissue (WAT) is only moderately dependent on NAD+ biosynthesis, and the skeletal muscle clock is completely refractory to loss of NAMPT. In BAT and WAT, NAMPT differentially orchestrates oscillation of clock-controlled gene networks and the diurnality of metabolite levels. NAMPT coordinates the rhythmicity of TCA cycle intermediates in BAT, but not in WAT, and loss of NAD+ abolishes these oscillations similarly to high-fat diet-induced circadian disruption. Moreover, adipose NAMPT depletion improved the ability of animals to defend body temperature during cold stress but in a time-of-day-independent manner. Thus, our findings reveal that peripheral molecular clocks and metabolic biorhythms are shaped in a highly tissue-specific manner by NAMPT-dependent NAD+ synthesis.


Asunto(s)
NAD , Nicotinamida Fosforribosiltransferasa , Animales , NAD/metabolismo , Nicotinamida Fosforribosiltransferasa/genética , Nicotinamida Fosforribosiltransferasa/metabolismo , Ritmo Circadiano/fisiología , Tejido Adiposo Pardo/metabolismo , Obesidad/metabolismo , Citocinas/metabolismo
7.
Proc Natl Acad Sci U S A ; 120(45): e2301534120, 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37903257

RESUMEN

L-type voltage-gated calcium (Ca2+) channels (L-VGCC) dysfunction is implicated in several neurological and psychiatric diseases. While a popular therapeutic target, it is unknown whether molecular mechanisms leading to disrupted L-VGCC across neurodegenerative disorders are conserved. Importantly, L-VGCC integrate synaptic signals to facilitate a plethora of cellular mechanisms; however, mechanisms that regulate L-VGCC channel density and subcellular compartmentalization are understudied. Herein, we report that in disease models with overactive mammalian target of rapamycin complex 1 (mTORC1) signaling (or mTORopathies), deficits in dendritic L-VGCC activity are associated with increased expression of the RNA-binding protein (RBP) Parkinsonism-associated deglycase (DJ-1). DJ-1 binds the mRNA coding for the alpha and auxiliary Ca2+ channel subunits CaV1.2 and α2δ2, and represses their mRNA translation, only in the disease states, specifically preclinical models of tuberous sclerosis complex (TSC) and Alzheimer's disease (AD). In agreement, DJ-1-mediated repression of CaV1.2/α2δ2 protein synthesis in dendrites is exaggerated in mouse models of AD and TSC, resulting in deficits in dendritic L-VGCC calcium activity. Finding of DJ-1-regulated L-VGCC activity in dendrites in TSC and AD provides a unique signaling pathway that can be targeted in clinical mTORopathies.


Asunto(s)
Enfermedad de Alzheimer , Esclerosis Tuberosa , Animales , Ratones , Enfermedad de Alzheimer/genética , Calcio/metabolismo , Canales de Calcio Tipo L/genética , Canales de Calcio Tipo L/metabolismo , Dendritas/metabolismo , Mamíferos/metabolismo , Esclerosis Tuberosa/genética
8.
Proc Natl Acad Sci U S A ; 119(52): e2203894119, 2022 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-36534812

RESUMEN

The gut microbiota and liver cancer have a complex interaction. However, the role of gut microbiome in liver tumor initiation remains unknown. Herein, liver cancer was induced using hydrodynamic transfection of oncogenes to explore liver tumorigenesis in mice. Gut microbiota depletion promoted liver tumorigenesis but not progression. Elevated sterol regulatory element-binding protein 2 (SREBP2) was observed in mice with gut flora disequilibrium. Pharmacological inhibition of SREBP2 or Srebf2 RNA interference attenuated mouse liver cancer initiation under gut flora disequilibrium. Furthermore, gut microbiota depletion impaired gut tryptophan metabolism to activate aryl hydrocarbon receptor (AhR). AhR agonist Ficz inhibited SREBP2 posttranslationally and reversed the tumorigenesis in mice. And, AhR knockout mice recapitulated the accelerated liver tumorigenesis. Supplementation with Lactobacillus reuteri, which produces tryptophan metabolites, inhibited SREBP2 expression and tumorigenesis in mice with gut flora disequilibrium. Thus, gut flora disequilibrium promotes liver cancer initiation by modulating tryptophan metabolism and up-regulating SREBP2.


Asunto(s)
Disbiosis , Microbioma Gastrointestinal , Neoplasias Hepáticas , Proteína 2 de Unión a Elementos Reguladores de Esteroles , Animales , Ratones , Carcinogénesis , Neoplasias Hepáticas/metabolismo , Receptores de Hidrocarburo de Aril/metabolismo , Proteína 2 de Unión a Elementos Reguladores de Esteroles/metabolismo , Triptófano/metabolismo , Disbiosis/complicaciones
9.
BMC Biol ; 22(1): 240, 2024 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-39443951

RESUMEN

BACKGROUND: The rumen microbiome plays an essential role in maintaining ruminants' growth and performance even under extreme environmental conditions, however, which factors influence rumen microbiome stability when ruminants are reared in such habitats throughout the year is unclear. Hence, the rumen microbiome of yak (less domesticated) and cattle (domesticated) reared on the Qinghai-Tibetan Plateau through the year were assessed to evaluate temporal changes in their composition, function, and stability. RESULTS: Rumen fermentation characteristics and pH significantly shifted across seasons in both cattle and yak, but the patterns differed between the two ruminant species. Ruminal enzyme activity varied with season, and production of xylanase and cellulase was greater in yak compared to cattle in both fall and winter. The rumen bacterial community varied with season in both yak and cattle, with higher alpha diversity and similarity (beta diversity) in yak than cattle. The diversity indices of eukaryotic community did not change with season in both ruminant species, but higher similarity was observed in yak. In addition, the similarity of rumen microbiome functional community was higher in yak than cattle across seasons. Moreover, yak rumen microbiome encoded more genes (GH2 and GH3) related to cellulose and hemicellulose degradation compared to cattle, and a new enzyme family (GH160) gene involved in oligosaccharides was uniquely detected in yak rumen. The season affected microbiome attenuation and buffering values (stability), with higher buffering value in yak rumen microbiome than cattle. Positive correlations between antimicrobial resistance gene (dfrF) and CAZyme family (GH113) and microbiome stability were identified in yak, but such relationship was negatively correlated in cattle. CONCLUSIONS: The findings of the potential of cellulose degradation, the relationship between rumen microbial stability and the abundance of functional genes varied differently across seasons and between yak and cattle provide insight into the mechanisms that may underpin their divergent adaptation patterns to the harsh climate of the Qinghai-Tibetan Plateau. These results lay a solid foundation for developing strategies to maintain and improve rumen microbiome stability and dig out the potential candidates for manufacturing lignocellulolytic enzymes in the yak rumen to enhance ruminants' performance under extreme environmental conditions.


Asunto(s)
Microbioma Gastrointestinal , Rumen , Estaciones del Año , Animales , Bovinos , Rumen/microbiología , Microbioma Gastrointestinal/fisiología , Microbiota , Adaptación Fisiológica , Bacterias/genética , Bacterias/clasificación
10.
Med Res Rev ; 44(3): 1013-1054, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38140851

RESUMEN

The burgeoning prodrug strategy offers a promising avenue toward improving the efficacy and specificity of cytotoxic drugs. Elevated intracellular levels of glutathione (GSH) have been regarded as a hallmark of tumor cells and characteristic feature of the tumor microenvironment. Considering the pivotal involvement of elevated GSH in the tumorigenic process, a diverse repertoire of GSH-triggered prodrugs has been developed for cancer therapy, facilitating the attenuation of deleterious side effects associated with conventional chemotherapeutic agents and/or the attainment of more efficacious therapeutic outcomes. These prodrug formulations encompass a spectrum of architectures, spanning from small molecules to polymer-based and organic-inorganic nanomaterial constructs. Although the GSH-triggered prodrugs have been gaining increasing interests, a comprehensive review of the advancements made in the field is still lacking. To fill the existing lacuna, this review undertakes a retrospective analysis of noteworthy research endeavors, based on a categorization of these molecules by their diverse recognition units (i.e., disulfides, diselenides, Michael acceptors, and sulfonamides/sulfonates). This review also focuses on explaining the distinct benefits of employing various chemical architecture strategies in the design of these prodrug agents. Furthermore, we highlight the potential for synergistic functionality by incorporating multiple-targeting conjugates, theranostic entities, and combinational treatment modalities, all of which rely on the GSH-triggering. Overall, an extensive overview of the emerging field is presented in this review, highlighting the obstacles and opportunities that lie ahead. Our overarching goal is to furnish methodological guidance for the development of more efficacious GSH-triggered prodrugs in the future. By assessing the pros and cons of current GSH-triggered prodrugs, we expect that this review will be a handful reference for prodrug design, and would provide a guidance for improving the properties of prodrugs and discovering novel trigger scaffolds for constructing GSH-triggered prodrugs.


Asunto(s)
Antineoplásicos , Profármacos , Humanos , Profármacos/farmacología , Profármacos/química , Estudios Retrospectivos , Antineoplásicos/farmacología , Antineoplásicos/química , Glutatión/química , Línea Celular Tumoral
11.
Immunology ; 171(4): 566-582, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38158796

RESUMEN

The spleen is essential for lymphocyte proliferation, which is associated to sepsis prognosis. Adenosine 2A receptor (A2AR) blocking promotes lymphocyte proliferation in sepsis, however the mechanism is uncertain. Our sepsis cecum ligation perforation model showed that blocking A2AR increased survival and CD4+ cell numbers in a spleen-dependent mechanism. The sequencing of the transcriptome of the spleen indicated alterations in the expression of genes involved in the control of lymphocyte proliferation by inhibiting A2AR, including a reduction in the expression of PD-L1. Flow cytometry analysis of PD-L1 expression intensity in splenic cell subpopulations revealed that the Treg cell subpopulation was the strongest PD-L1-expressing cell population, and Treg PD-L1 expression decreased after blocking A2AR. In vitro activation of A2AR was able to upregulate PD-L1 expression of Treg and boost Treg capacity to limit lymphocyte proliferation, while blockage of PD-L1 partly reduced A2AR-activated Treg's ability to inhibit lymphocyte proliferation. In addition, blocking CREB phosphorylation significantly inhibited A2AR-induced PD-L1 expression. According to the findings of our research, inhibiting A2AR improves the prognosis of sepsis by lowering the level of PD-L1 expression by Treg in the spleen and reducing the inhibition of lymphocyte proliferation.


Asunto(s)
Sepsis , Bazo , Humanos , Bazo/metabolismo , Linfocitos T Reguladores/metabolismo , Antagonistas de Receptores Purinérgicos P1 , Antígeno B7-H1/metabolismo , Adenosina , Proliferación Celular
12.
J Am Chem Soc ; 146(43): 29391-29401, 2024 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-39418220

RESUMEN

Sodium-ion batteries suffer from kinetic problems stemming from sluggish ion transport across the electrode-electrolyte interface, causing rapid energy decay during fast-charging or low-temperature operation. One exciting prospect to enhance kinetics is constructing neuron-like electrodes that emulate fast signal transmission in a nervous system. It has been considered that these bioinspired designs enhance electron/ion transport of the electrodes through carbon networks. However, whether they can avoid sluggish charge transfer at the electrode-electrolyte interface remains unknown. By connecting the openings of carbon nanotubes with the surface of carbon-coated Na3V2O2(PO4)2F cathode nanoparticles, here we use carbon nanotubes to trap Na+ ions released from the nanoparticles during charge. Therefore, Na+ movement is confined only inside the neuron-like cathode, eliminating ion transport between the electrolyte and cathode, which has been scarcely achieved in conventional batteries. As a result, a 14-fold reduction in interfacial charge transfer resistance is achieved when compared to unmodified cathodes, leading to superior fast-charging performance and excellent cyclability up to 200C, and surprisingly, reversible operation at low temperatures down to -60 °C without electrolyte modification, surpassing other Na3V2O2(PO4)2F-based batteries reported to date. As battery operation has relied on charge transfer at the electrode-electrolyte interface for over 200 years, our approach departs from this traditional ion transport paradigm, paving the way for building better batteries that work under harsh conditions.

13.
Neurobiol Dis ; 201: 106664, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39278510

RESUMEN

AMP-activated protein kinase (AMPK) is an αßγ heterotrimer protein kinase that functions as a molecular sensor to maintain energy homeostasis. Accumulating evidence suggests a role of AMPK signaling in the regulation of synaptic plasticity and cognitive function; however, isoform-specific roles of AMPK in the central nervous system (CNS) remain elusive. Regulation of the AMPK activities has focused on the manipulation of the α or γ subunit. Meanwhile, accumulating evidence indicates that the ß subunit is critical for sensing nutrients such as fatty acids and glycogen to control AMPK activity. Here, we generated transgenic mice with conditional suppression of either AMPKß1 or ß2 in neurons and characterized potential isoform-specific roles of AMPKß in cognitive function and underlying mechanisms. We found that AMPKß2 (but not ß1) suppression resulted in impaired recognition memory, reduced hippocampal synaptic plasticity, and altered structure of hippocampal postsynaptic densities and dendritic spines. Our study implicates a role for the AMPKß2 isoform in the regulation of synaptic and cognitive function.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Hipocampo , Ratones Transgénicos , Plasticidad Neuronal , Neuronas , Reconocimiento en Psicología , Animales , Plasticidad Neuronal/fisiología , Proteínas Quinasas Activadas por AMP/metabolismo , Reconocimiento en Psicología/fisiología , Neuronas/metabolismo , Ratones , Hipocampo/metabolismo , Ratones Endogámicos C57BL , Masculino , Espinas Dendríticas/metabolismo , Isoenzimas/metabolismo
14.
Mol Med ; 30(1): 7, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38200442

RESUMEN

BACKGROUND: Intervertebral disc degeneration (IDD) is considered an important pathological basis for spinal degenerative diseases. Tissue engineering is a powerful therapeutic strategy that can effectively restore the normal biological properties of disc units. In this study, hydrogels loaded with growth/differentiation factor 5 (GDF5) and stem cells were combined to provide an effective strategy for nucleus pulposus regeneration. METHODS: Nucleus pulposus stem cells (NPSCs) were obtained by low-density inoculation and culture, and their stem cell characteristics were verified by flow cytometry and a tri-lineage-induced differentiation experiment. A decellularized nucleus pulposus matrix (DNPM) and chitosan hybrid hydrogel was prepared, and GDF5-loaded poly(lactic-co-glycolic acid) (PLGA) microspheres were incorporated into the hydrogels to obtain a composite hydrogels with GDF5-loaded microspheres. Taking bone marrow mesenchymal stem cells (BMSCs) as a reference, the effect of composite hydrogels with GDF5-loaded microspheres on the chondrogenic differentiation of NPSCs was evaluated. A model of intervertebral disc degeneration induced by acupuncture on the tail of rats was constructed, and the repair effect of composite hydrogels with GDF5-loaded microspheres combined with NPSCs on IDD was observed. RESULTS: Stem cell phenotype identification, stemness gene expression and tri-lineage-induced differentiation confirmed that NPSCs had characteristics similar to those of BMSCs. The rat DNPM and chitosan hybrid hydrogels had good mechanical properties, and the GDF5-loaded microspheres sustainably released GDF5. NPSCs grew normally in the composite hydrogels and gradually expressed a chondrocyte phenotype. Animal experiments showed that the composite hydrogels with GDF5-loaded microspheres combined with NPSCs effectively promoted nucleus pulposus regeneration and that the effect of the hydrogels on the repair of IDD was significantly better than that of BMSCs. CONCLUSION: GDF5-loaded microspheres combined with DNPM/chitosan composite hydrogels can effectively promote the differentiation of NPSCs into nucleus pulposus-like cells and effectively preventIDD.


Asunto(s)
Quitosano , Degeneración del Disco Intervertebral , Núcleo Pulposo , Animales , Ratas , Hidrogeles , Degeneración del Disco Intervertebral/terapia , Microesferas , Células Madre
15.
Anal Chem ; 96(19): 7669-7678, 2024 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-38708542

RESUMEN

Protein tyrosine kinase-7 (PTK7) has been reported as a vital participant in the Wnt signaling pathway, influencing tumorigenesis and metastasis. However, their specific roles in the mechanisms underlying cancer development and progression remain elusive. Here, using direct stochastic optical reconstruction microscopy (dSTORM) with aptamer-probe labeling, we first revealed that a weakening clustering distribution of PTK7 on the basal membranes happened as cellular migration increased during cancer progression. This correspondence was further supported by a diminished aggregated state of PTK7 caused by direct enhancement of cell migration. By comparing the alterations in PTK7 distribution with activation or inhibition of specific Wnt signaling pathway, we speculated that PTK7 could modulate cell migration by participating in the interplay between canonical Wnt (in MCF7 cells) and noncanonical Wnt signals (in MDA-MB-231 cells). Furthermore, we discovered that the spatial distribution morphology of PTK7 was also subject to the hydrolysis ability and activation state of the related hydrolase Matrix metallopeptidase14 (MMP14). This function-related specific assembly of PTK7 reveals a clear relationship between PTK7 and cancer. Meanwhile, potential molecular interactions predicted by the apparent assembly morphology can promote a deep understanding of the functional mechanism of PTK7 in cancer progress.


Asunto(s)
Proteínas Tirosina Quinasas Receptoras , Humanos , Proteínas Tirosina Quinasas Receptoras/metabolismo , Movimiento Celular , Moléculas de Adhesión Celular/metabolismo , Vía de Señalización Wnt , Línea Celular Tumoral , Neoplasias/metabolismo , Neoplasias/patología , Metaloproteinasa 14 de la Matriz/metabolismo
16.
Cancer Immunol Immunother ; 73(12): 244, 2024 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-39358560

RESUMEN

PURPOSE: This phase I/II trial (ChiCTR2000032879) assessed the safety and efficacy of toripalimab combined with chemoradiotherapy for locally advanced cervical squamous cell carcinoma. METHODS AND MATERIALS: Twenty-two patients, regardless of their programmed death ligand-1 (PD-L1) status, received toripalimab combined with concurrent chemoradiotherapy (CCRT). CCRT included cisplatin (40 mg/m2, once weekly for 5 weeks), radiotherapy (45-50.4 Gy/25-28 Fx, 5 fractions weekly), followed by brachytherapy (24-30 Gy/3-5 Fx) and toripalimab (240 mg, intravenous) on days 1, 22 and 43 during CCRT. The primary endpoints were safety and 2-year progression-free survival (PFS). The secondary endpoints included 2-year local control (LC), local regional control and overall survival (OS). RESULTS: All patients successfully completed CCRT and toripalimab treatment. Grade III and higher adverse events (AEs) were observed in 11 patients (11/22, 50%), and no patient experienced grade V AEs. The objective response rate (ORR) was 100%. At the data cutoff (June 30, 2023), the median follow-up was 31.8 months (9.5 to 37.8 months). The 2-year PFS rate was 81.8%. The 2-year LC and local regional control rates were both 95.5%, and the 2-year OS rate was 90.9%. CONCLUSIONS: Toripalimab combined with CCRT achieved good tolerance and showed promising anti-tumor effects in patients with locally advanced cervical cancer.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Carcinoma de Células Escamosas , Quimioradioterapia , Neoplasias del Cuello Uterino , Humanos , Femenino , Neoplasias del Cuello Uterino/terapia , Neoplasias del Cuello Uterino/mortalidad , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/patología , Persona de Mediana Edad , Quimioradioterapia/métodos , Carcinoma de Células Escamosas/terapia , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/tratamiento farmacológico , Anciano , Adulto , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos
17.
Small ; : e2404452, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39248686

RESUMEN

Aqueous rechargeable lithium-ion batteries (ARLIBs) are extensively researched due to their inherent safety, typical affordability, and potential high energy density. However, fabricating ARLIBs with both high energy density and power performance remains challenging. Herein, based on cyanoethyl-modified bacterial cellulose nanofibers (CBCNs), a multifunctional fast ion transport framework is developed to construct the flexible free-standing ARLIBs with high areal loading and excellent rate performance. Benefiting from the unique merits of CBCNs, such as ultra-high aspect ratio, excellent toughness, superior adhesion, good lithiophilicity and ideal stability, the flexible free-standing and highly robust electrodes are fabricated and exhibit a long-term stable cycling of 1200 cycles with a high specific capacity of 117 mAh∙g-1 at 15 C. Remarkably, the corresponding full cell with the free-standing high mass loading (45.5 mg∙cm-2) electrodes under the condition of ultra-low addition of battery binder demonstrates a cycle lifespan of over 1000 cycles with a specific capacity of 120 mAh∙g-1 and a capacity decay as low as 0.03% per cycle, which is far superior to those of almost all previous reports. This work provides a strategy for constructing ARLIBs with high energy density and power performance by introducing a unique fast ion transport nanofiber framework.

18.
Small ; 20(25): e2309906, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38221704

RESUMEN

On-site hydrogen production from liquid organic hydrogen carriers e.g., methanol provides an emerging strategy for the safe storage and transportation of hydrogen. Herein, a catalytic architecture consisting of nickel-cobalt nanoclusters dispersed on gallium nitride nanowires supported by silicon for light-driven hydrogen production from methanol is reported. By correlative microscopic, spectroscopic characterizations, and density functional theory calculations, it is revealed that NiCo nanoclusters work in synergy with GaN nanowires to enable the achievement of a significantly reduced activation energy of methanol dehydrogenation by switching the potential-limiting step from *CHO → *CO to *CH3O → *CH2O. In combination with the marked photothermal effect, a high hydrogen rate of 5.62 mol·gcat-1·h-1 with a prominent turnover frequency of 43,460 h-1 is achieved at 5 Wcm-2 without additional energy input. Remarkably, the synergy between Co and Ni, in combination with the unique surface of GaN, renders the architecture with outstanding resistance to sintering and coking. The architecture thereby exhibits a high turnover number of >16,310,000 over 600 h. Outdoor testing validates the viability of the architecture for active and robust hydrogen evolution under natural concentrated sunlight. Overall, this work presents a promising architecture for on-site hydrogen production from CH3OH by virtually unlimited solar energy.

19.
Electrophoresis ; 45(5-6): 517-527, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38100194

RESUMEN

Rwanda is known as the heart of Africa, reflecting the history of the world. Colonization and genocide have led to Rwanda's existing genetic structure. Herein, we used massively parallel sequencing to analyze 296 loci in 185 Rwandans and constructed a database for Rwandan forensic data for the first time. We found the following results: First, forensic parameters demonstrated that all loci were highly informative and could be used for forensic identification and paternity tests in Rwandans. Second, we found that the differences in genetic background between Rwandans and other African populations were similar but slight, as indicated by the massively parallel sequencing panel. Rwandans belonged to the African population and were inseparable from populations from neighboring countries. Also, Rwandans were closer to the European and American populations because of colonization, war, and other reasons. There was no scientific basis for racial classification established by colonization. Further research still needs to be carried out on more loci and larger Rwandan samples.


Asunto(s)
Dinámica Poblacional , Rwanda , Demografía , África
20.
Cytokine ; 175: 156481, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38159468

RESUMEN

Murine Natural Killer cells were cultivated in vitro to isolate NK-derived exosomes. Subsequent quantification via qPCR confirmed enrichment of miR-1249-3p. Ana-1 murine macrophages were cultured in vitro and subsequently inoculated with Mycobacterium tuberculosis (MTB) strain H37Rv. NK-exo and NK-exo miR-1249-3p were separately applied to the infection model, followed by immunological assays conducted post-48-hour co-culture. Western blot analyses corroborated that NK-exo exhibited exosomal marker proteins Granzyme A (GzmA), Granzyme B (GzmB), and Perforin (PFN), alongside a notable enrichment of miR-1249-3p. Functionally, NK-exo augmented the expression levels of Caspase-9,-8, and -3, as well as PARP, while attenuating the expression of NLRP3, ASC, and Cleaved-Caspase-1. Furthermore, qPCR demonstrated an up-regulation of Caspase-9, -8, and -3, along with pro-apoptotic factors Bax and Bid, and a concomitant down-regulation of the anti-apoptotic factor Bcl-2. The expression levels of inflammatory markers ASC, NLRP3, Cleaved-Caspase-1, and IL-1ß were concomitantly decreased. ELISA findings indicated diminished levels of TNF-α and ROS secretion. NK-exo miR-1249-3p specifically targeted and attenuated the expression of SKOR-1, engendering up-regulation of apoptosis-associated proteins and down-regulation of inflammation-related proteins, consequently affecting cellular fate.Our empirical evidence substantiates that NK-exo induces macrophage apoptosis, thereby mitigating MTB survival. Furthermore, NK-exo miR-1249-3p directly targets and inhibits SKOR-1 expression, leading to macrophage apoptosis and consequently hampering the proliferation of MTB. The data implicate the potential therapeutic relevance of NK-exo and miR-1249-3p in managing drug-resistant tuberculosis.


Asunto(s)
Exosomas , MicroARNs , Mycobacterium tuberculosis , Animales , Ratones , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Caspasa 9/metabolismo , Mycobacterium tuberculosis/metabolismo , Exosomas/metabolismo , Macrófagos/metabolismo , MicroARNs/metabolismo
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