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1.
J Biol Chem ; 287(27): 22533-48, 2012 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-22563078

RESUMEN

The nucleolar 58-kDa microspherule protein (MSP58) protein is a candidate oncogene implicated in modulating cellular proliferation and malignant transformation. In this study, we show that knocking down MSP58 expression caused aneuploidy and led to apoptosis, whereas ectopic expression of MSP58 regulated cell proliferation in a context-dependent manner. Specifically, ectopic expression of MSP58 in normal human IMR90 and Hs68 diploid fibroblasts, the H184B5F5/M10 mammary epithelial cell line, HT1080 fibrosarcoma cells, primary mouse embryonic fibroblasts, and immortalized NIH3T3 fibroblasts resulted in induction of premature senescence, an enlarged and flattened cellular morphology, and increased senescence-associated ß-galactosidase activity. MSP58-driven senescence was strictly dependent on the presence of functional p53 as revealed by the fact that normal cells with p53 knockdown by specific shRNA or cells with a mutated or functionally impaired p53 pathway were effective in bypassing MSP58-induced senescence. At least two senescence mechanisms are induced by MSP58. First, MSP58 activates the DNA damage response and p53/p21 signaling pathways. Second, MSP58, p53, and the SWI/SNF chromatin-remodeling subunit Brahma-related gene 1 (BRG1) form a ternary complex on the p21 promoter and collaborate to activate p21. Additionally, MSP58 protein levels increased in cells undergoing replicative senescence and stress-induced senescence. Notably, the results of analyzing expression levels of MSP58 between tumors and matched normal tissues showed significant changes (both up- and down-regulation) in its expression in various types of tumors. Our findings highlight new aspects of MSP58 in modulating cellular senescence and suggest that MSP58 has both oncogenic and tumor-suppressive properties.


Asunto(s)
Senescencia Celular/fisiología , ADN Helicasas/metabolismo , Proteínas Nucleares/metabolismo , Proteína Oncogénica p21(ras)/metabolismo , Proteínas de Unión al ARN/metabolismo , Factores de Transcripción/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Animales , Apoptosis/fisiología , División Celular/fisiología , Línea Celular Transformada , Línea Celular Tumoral , Transformación Celular Neoplásica/metabolismo , Daño del ADN/fisiología , ADN Helicasas/genética , Fibrosarcoma , Regulación Neoplásica de la Expresión Génica/fisiología , Técnicas de Silenciamiento del Gen , Humanos , Glándulas Mamarias Humanas/citología , Glándulas Mamarias Humanas/fisiología , Ratones , Células 3T3 NIH , Proteínas Nucleares/genética , Proteínas de Unión al ARN/genética , Transducción de Señal/fisiología , Estrés Fisiológico/fisiología , Factores de Transcripción/genética
2.
Front Neuroanat ; 16: 968320, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36032994

RESUMEN

Recently, researchers have paid progressively more attention to the study of neural development in infant rats. However, due to the lack of complete intracerebral localization information, such as clear nuclear cluster boundaries, identified main brain structures, and reliable stereotaxic coordinates, it is difficult and restricted to apply technical neuroscience to infant rat's brain. The present study was undertaken to refine the atlas of infant rats. As such, we established a stereotaxic atlas of the infant rat's brain at postnatal days 7-13. Furthermore, dye calibration surgery was performed in P7-P13 infant rats by injecting Methylene blue, and sections were incubated in Nissl solutions. From the panoramic images of the brain sections, atlases were made. Our article has provided the appearance and measurements of P7-P13 Sprague-Dawley rat pups. Whereas the atlas contains a series of about 530 coronal brain section images from olfactory bulbs to the brainstem, a list of abbreviations of the main brain structures, and reliable stereotaxic coordinates, which were demonstrated by vertical and oblique injections with fluorescent dye DiI. The present findings demonstrated that our study of P7-P13 atlases has reasonable nucleus boundaries and accurate and good repeatability of stereotaxic coordinates, which can make up for the shortage of postnatal rat brain atlas currently in the field.

3.
Artículo en Inglés | MEDLINE | ID: mdl-36293678

RESUMEN

The ontogenetic sleep hypothesis suggested that rapid eye movement (REM) sleep is ontogenetically primitive. Namely, REM sleep plays an imperative role in the maturation of the central nervous system. In coincidence with a rapidly developing brain during the early period of life, a remarkably large amount of REM sleep has been identified in numerous behavioral and polysomnographic studies across species. The abundant REM sleep appears to serve to optimize a cerebral state suitable for homeostasis and inherent neuronal activities favorable to brain maturation, ranging from neuronal differentiation, migration, and myelination to synaptic formation and elimination. Progressively more studies in Mammalia have provided the underlying mechanisms involved in some REM sleep-related disorders (e.g., narcolepsy, autism, attention deficit hyperactivity disorder (ADHD)). We summarize the remarkable alterations of polysomnographic, behavioral, and physiological characteristics in humans and Mammalia. Through a comprehensive review, we offer a hybrid of animal and human findings, demonstrating that early-life REM sleep disturbances constitute a common feature of many neurodevelopmental disorders. Our review may assist and promote investigations of the underlying mechanisms, functions, and neurodevelopmental diseases involved in REM sleep during early life.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Trastornos del Sueño-Vigilia , Animales , Humanos , Sueño REM/fisiología , Sueño , Encéfalo/fisiología
4.
Front Neurol ; 10: 873, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31456739

RESUMEN

Sleep-wake development in postnatal rodent life could reflect the brain maturational stages. As the altricial rodents, rats are born in a very undeveloped state. Continuous sleep recording is necessary to study the sleep-wake cycle profiles. However, it is difficult to realize in infant rats since they rely on periodic feeding before weaning and constant warming and appropriate EEG electrodes. We developed a new approach including two types of EEG electrodes and milk-feeding system and temperature-controlled incubator to make continuously polysomnographic (PSG) recording possible. The results showed that there was no evident difference in weight gaining and behaviors between pups fed through the milk-feeding system and warmed with temperature-controlled incubator and those kept with their dam. Evolutional profiles of EEG and electromyogram (EMG) activities across sleep-wake states were achieved perfectly during dark and light period from postnatal day (P) 11 to P75 rats. The ontogenetic features of sleep-wake states displayed that the proportion of rapid eye movement (REM) was 57.0 ± 2.4% and 59.7 ± 1.7% and non-REM (NREM) sleep was 5.2 ± 0.8% and 4.9 ± 0.5% respectively, in dark and light phase at P11, and then REM sleep progressively decreased and NREM sleep increased with age. At P75, REM sleep in dark and light phase respectively, reduced to 6.3 ± 0.6% and 6.9 ± 0.5%, while NREM correspondingly increased to 37.5 ± 2.1% and 58.4 ± 1.7%. Wakefulness from P11 to P75 in dark phase increased from 37.8 ± 2.2% to 56.2 ± 2.6%, but the change in light phase was not obvious. P20 pups began to sleep more in light phase than in dark phase. The episode number of vigilance states progressively decreased with age, while the mean duration of that significantly increased. EEG power spectra in 0.5-4 Hz increased with age accompanied with prolonged duration of cortical slow wave activity. Results also indicated that the dramatic changes of sleep-wake cycle mainly occurred in the first month after birth. The novel approaches used in our study are reliable and valid for continuous PSG recording for infant rats and unravel the ontogenetic features of sleep-wake cycle.

5.
Toxicon ; 160: 23-28, 2019 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-30772435

RESUMEN

Phytoremediation with aquatic macrophyte has been considered as an eco-friendly technique for controlling harmful cyanobacteria outbreak and proven to be effective. The conventional water quality parameters are frequently measured to evaluate the effectiveness of phytoremediation. However, the concentration of microcystin-leucine-arginine (MC-LR) in different vegetated water still remains uncertain. In this study, the contents of MC-LR in four macrophyte-vegetated lagoons were determined by solid phase extraction and ultra-high-performance liquid chromatography with tandem mass spectrometry technology. Results indicated that MC-LR was found in Nymphaea tetragona lagoon (lagoon-S), Vallisneria spiralis lagoon (lagoon-B) and another Vallisneria spiralis lagoon (lagoon-J). Only in lagoon dominated by Pistia stratiotes L. (lagoon-D), MC-LR concentration was undiscovered regardless of seasonal variation. The levels of MC-LR varied seasonally and were affected by the different vegetated aquatic macrophytes. The results suggest that in addition to conventional physicochemical parameters and indicators of water quality, MC-LR levels should be taken into consideration when the effectiveness of phytoremediation is assessed.


Asunto(s)
Biodegradación Ambiental , Microcistinas/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Araceae , Cromatografía Líquida de Alta Presión , Hydrocharitaceae , Toxinas Marinas , Nymphaea , Estaciones del Año , Espectrometría de Masas en Tándem , Aguas Residuales , Purificación del Agua/métodos
6.
Front Cell Neurosci ; 12: 64, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29559896

RESUMEN

Disturbed sleep is a common subjective complaint among individuals with anxiety disorders. Sleep deprivation increases general and specific anxiety symptoms among healthy individuals. The amygdala is critical for regulating anxiety and also involved in mediating the effects of emotions on sleep. Neuropeptide S (NPS) and NPS receptors (NPSR) are reported as a novel endogenous arousal and anxiolytic system, but it is unclear yet whether this system is involved in anxiety-like behavior and sleep caused by sleep deprivation, and how it plays anxiolytic effect underlying the comorbid condition. In the present study, we demonstrate that paradoxical sleep deprivation (PSD) induced by modified multiple platform method (MMPM) for 24 h caused anxiety-like behavior, a prolonged sleep latency and subsequent paradoxical sleep (PS) rebound accompanied by an increase in electroencephalogram (EEG) theta (4.5-8.5 Hz) activities across light and dark phase in rats. The increase of PS after PSD was due to an increase of episode number during light phase and both episode number and duration during dark phase. Central action of NPS (1 nmol) attenuated PSD-induced anxiety-like behavior, and altered PSD-induced sleep-wake disturbances through increasing wakefulness, and suppressing PS and EEG theta activities. The reduction in PS time following NPS administration during light phase was because of a decreased episode number. Furthermore, sleep amount in 24 h in PSD rats given NPS was lesser than that given saline. PSD significantly enhanced NPSR mRNA expression level in the amygdala. NPS remarkably increased the number of Fos-ir neurons in the basolateral amygdala (BLA), the central amygdala (CeA) and medial amygdala (MeA). The majority of Fos-ir neurons induced by NPS also expressed NPSR. These results suggest that NPSR upregulation in the amygdala is presumably related to the PSD-induced anxiety-like behavior and sleep disturbances, and that NPS counteracts PSD-induced anxiety-like behavior and sleep disturbances possibly through activating the neurons bearing NPSR in the amygdala. In addition, the little sleep increase in PSD rats treated with NPS suggests that NPS can function as an anxiolytic without causing a subsequent sleep rebound.

7.
Artículo en Inglés | MEDLINE | ID: mdl-28029125

RESUMEN

In this study, we developed curcumin-encapsulated hyaluronic acid-polylactide nanoparticles (CEHPNPs) to be used for liver fibrosis amelioration. CD44, the hyaluronic acid (HA) receptor, is upregulated on the surface of cancer cells and on activated hepatic stellate cells (aHSCs) rather than normal cells. CEHPNPs could bind to CD44 and be internalized effectively through endocytosis to release curcumin, a poor water-soluble liver protective agent. Thus, CEHPNPs were potentially not only improving drug efficiency, but also targeting aHSCs. HA and polylactide (PLA) were crosslinked by adipic acid dihydrazide (ADH). The synthesis of HA-PLA was monitored by Fourier-transform infrared (FTIR) and Nuclear Magnetic Resonance (NMR). The average particle size was approximately 60-70 nm as determined by dynamic light scattering (DLS) and scanning electron microscope (SEM). Zeta potential was around -30 mV, which suggested a good stability of the particles. This drug delivery system induced significant aHSC cell death without affecting quiescent HSCs, hepatic epithelial, and parenchymal cells. This system reduced drug dosage without sacrificing therapeutic efficacy. The cytotoxicity IC50 (inhibitory concentration at 50%) value of CEHPNPs was approximately 1/30 to that of the free drug treated group in vitro. Additionally, the therapeutic effects of CEHPNPs were as effective as the group treated with the same curcumin dose intensity in vivo. CEHPNPs significantly reduced serum aspartate transaminase/alanine transaminase (ALT/AST) significantly, and attenuated tissue collagen production and cell proliferation as revealed by liver biopsy. Conclusively, the advantages of superior biosafety and satisfactory therapeutic effect mean that CEHPNPs hold great potential for treating hepatic fibrosis.


Asunto(s)
Curcumina/administración & dosificación , Sistemas de Liberación de Medicamentos , Ácido Hialurónico/administración & dosificación , Cirrosis Hepática/tratamiento farmacológico , Nanopartículas/administración & dosificación , Poliésteres/administración & dosificación , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Curcumina/química , Curcumina/uso terapéutico , Humanos , Receptores de Hialuranos/metabolismo , Ácido Hialurónico/química , Ácido Hialurónico/uso terapéutico , Cirrosis Hepática/sangre , Cirrosis Hepática/inducido químicamente , Masculino , Ratones Endogámicos BALB C , Nanopartículas/química , Nanopartículas/uso terapéutico , Poliésteres/química , Poliésteres/uso terapéutico , Sustancias Protectoras/administración & dosificación , Sustancias Protectoras/química , Sustancias Protectoras/uso terapéutico , Ratas , Tioacetamida
8.
Dalton Trans ; 44(37): 16294-303, 2015 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-26300343

RESUMEN

We demonstrated Au/ZnSn(OH)6 hollow nanocubes that exhibited extremely high photodegradation activity under ultraviolet and visible-light illumination. The pristine ZnSn(OH)6 hollow nanocubes can achieve a 100% photodegradation ratio within 20 min under ultraviolet-light illumination. The high photodegradation activity of ZnSn(OH)6 can be attributed to plenty of OH groups present in the polyhedral corner of the ZnSn(OH)6 that generate a large number of reactive hydroxyl radicals for degradation of dye molecules. High resolution transmission electron microscopy (HRTEM) and scanning electron microscopy (SEM) images revealed that the size of the ZnSn(OH)6 and Au/ZnSn(OH)6 hollow nanocubes is ∼30-80 nm. After ZnSn(OH)6 nanocubes were decorated with Au, the heterostructures exhibited a significantly strong and widened absorption peak in the range 450-750 nm because of the surface plasmon resonance (SPR) effect, and therefore showed an excellent photodegradation activity under visible-light illumination. The rate constant k of Au/ZnSn(OH)6 is as high as 51.8 L mol(-1) min(-1) under UV-light illumination. This value is much higher than those reported so far. The hydroxyl groups essentially enhance the reaction rate and enable the active radicals to participate in the reaction for destruction of the Rhodamine B (RB) solution. Au/ZnSn(OH)6 has been successfully applied for preparing hybrid coating screens with polydimethylsiloxane (PDMS), which exhibited an excellent mechanical desirable durability and extended its feasible application in our daily lives.

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