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1.
ACS Appl Mater Interfaces ; 15(35): 41476-41482, 2023 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-37625012

RESUMEN

Developing highly active and robust oxygen catalysts is of great significance for the commercialization of Zn-air batteries (ZABs) with long-life stability. Herein, heterostructured catalysts comprising molybdenum carbide and metallic Co are prepared by a simple dicyandiamide-assisted pyrolysis strategy. Importantly, the crystalline phase of molybdenum carbide in the catalysts can be carefully regulated by adjusting the CoMo-imidazole precursor and dicyandiamide ratio. The electronic configuration of Co and Mo centers as well as the phase-dependent oxygen reduction reaction performance of these heterostructures (ß-Mo2C/Co, ß-Mo2C/η-MoC/Co, and η-MoC/Co) was disclosed. A highly active η-MoC/Co cathode enables ZABs with outstanding long-term stability over 850 h with a low voltage decaying rate of 0.06 mV·h-1 and high peak power density of 162 mW·cm-2. This work provides a new idea for the rational design of efficient and stable cathode catalysts for ZABs.

2.
Small ; 19(10): e2207517, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36650989

RESUMEN

Aqueous rechargeable zinc-ion batteries (ZIBs) have attracted burgeoning interests owing to the prospect in large-scale and safe energy storage application. Although manganese oxides are one of the typical cathodes of ZIBs, their practical usage is still hindered by poor service life and rate performance. Here, a MnO2 -carbon hybrid framework is reported, which is obtained in a reaction between the dimethylimidazole ligand from a rational designed MOF array and potassium permanganate, achieving ultralong-cycle-life ZIBs. The unique structural feature of uniform MnO2 nanocrystals which are well-distributed in the carbon matrix leads to a 90.4% capacity retention after 50 000 cycles. In situ characterization and theoretical calculations verify the co-ions intercalation with boosted reaction kinetics. The hybridization between MnO2 and carbon endows the hybrid with enhanced electrons/ions transport kinetics and robust structural stability. This work provides a facile strategy to enhance the battery performance of manganese oxide-based ZIBs.

3.
Int J Biol Macromol ; 214: 312-323, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-35714869

RESUMEN

Type 2 diabetes mellitus is a global disease that endangers human health, and the need for the development of nontoxic treatment candidates is urgent. In the present work, one homogeneous polysaccharide from Inonotus obliquus (IN) was isolated, and the protective effect and mechanism of IN on type 2 diabetes mellitus were investigated from the aspects of the intestinal barrier. IN mainly consisted of 9 monosaccharides with a Mw of 373 kDa. IN attenuated body weight loss, alleviated pathological damage, and suppressed the production of proinflammatory cytokines. Additionally, IN repaired the intestinal barrier by upregulating the expression of Ki-67, ZO-1 and MUC2. Furthermore, the abundance of Firmicutes was significantly increased with IN treatment, while the levels of Bacteroidetes were significantly inhibited. In conclusion, IN protected against type 2 diabetes mellitus by ameliorating intestinal barrier dysfunction and might serve as a novel drug candidate for type 2 diabetes mellitus.


Asunto(s)
Basidiomycota , Diabetes Mellitus Tipo 2 , Animales , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Carbohidratos de la Dieta , Humanos , Inonotus , Ratones , Polisacáridos/farmacología , Polisacáridos/uso terapéutico
4.
Chem Rec ; 22(10): e202200079, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35635378

RESUMEN

Aqueous rechargeable zinc-ion batteries (ZIBs) featuring competitive performance, low cost and high safety hold great promise for applications in grid-scale energy storage and portable electronic devices. Metal-organic frameworks (MOFs), relying on their large framework structure and abundant active sites, have been identified as promising materials in ZIBs. This review comprehensively presents the current development of MOF-based materials including MOFs and their derivatives in ZIBs, which begins with Zn storage mechanism of MOFs, followed by introduction of various types of MOF-based cathode materials (PB and PBA, Mn-based MOF, V-based MOF, conductive MOF and their derivatives), and the regulation approaches for Zn deposition behavior. The key factors and optimization strategies of MOF-based materials that affect ZIBs performance are emphasized and discussed. Finally, the challenges and further research directions of MOF-based materials for advanced zinc-ion batteries are provided.

5.
Nanotechnology ; 33(2)2021 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-34619665

RESUMEN

Constructing sophisticated hollow structure and exposing more metal sites in metal-organic frameworks (MOFs) can not only enhance their catalytic performance but also endow them with new functions. Herein, we present a facile coordinative reconstruction strategy to transform Ti-MOF polyhedron into nanosheet-assembled hollow structure with a large amount of exposed metal sites. Importantly, the reconstruction process relies on the esterification reaction between the organic solvent, i.e. ethanol and the carboxylic acid ligand, allowing the conversion of MOF without the addition of any other modulators and/or surfactants. Moreover, the surface and internal structure of the reconstructed MOF can be well tuned via altering the conversion time. Impressively, the reconstructed MOF exhibits ∼5.1-fold rate constant compared to the pristine one in an important desulfurization reaction for clean fuels production, i.e. the oxidation of dibenzothiophene.

6.
Small ; 17(33): e2101901, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34228384

RESUMEN

Although aqueous Zn-ion batteries (ZIBs) with low cost and high safety show great potential in large-scale energy storage system, metallic Zn anode still suffers from unsatisfactory cycle stability due to unregulated growth of Zn dendrites, corrosion, and formation of various side products during electrochemical reaction. Here, an ultrafast and simple method to achieve a stable Zn anode is developed. By simply immersing a Zn plate into an aqueous solution of CuSO4 for only 10-60 s, a uniform and robust protective layer (Zn4 SO4 (OH)6 ·5H2 O/Cu2 O) is formed on commercial Zn plate (Zn/ZCO), which enables uniform electric field distribution and controllable dendrite growth, leading to a long-term cycle life of over 1400 h and high average Coulombic efficiency (CE) of 99.2% at 2.0 mA cm-2 and 2.0 mAh cm-2 . These excellent characteristics of the prepared Zn anode show great potential in practical applications for high-performance aqueous Zn-ion batteries.

7.
BMC Cancer ; 21(1): 664, 2021 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-34082742

RESUMEN

BACKGROUND: Fenofibrate is a fibric acid derivative known to have a lipid-lowering effect. Although fenofibrate-induced peroxisome proliferator-activated receptor alpha (PPARα) transcription activation has been shown to play an important role in the malignant progression of gliomas, the underlying mechanisms are poorly understood. METHODS: In this study, we analyzed TCGA database and found that there was a significant negative correlation between the long noncoding RNA (lncRNA) HOTAIR and PPARα. Then, we explored the molecular mechanism by which lncRNA HOTAIR regulates PPARα in cell lines in vitro and in a nude mouse glioma model in vivo and explored the effect of the combined application of HOTAIR knockdown and fenofibrate treatment on glioma invasion. RESULTS: For the first time, it was shown that after knockdown of the expression of HOTAIR in gliomas, the expression of PPARα was significantly upregulated, and the invasion and proliferation ability of gliomas were obviously inhibited. Then, glioma cells were treated with both the PPARα agonist fenofibrate and si-HOTAIR, and the results showed that the proliferation and invasion of glioma cells were significantly inhibited. CONCLUSIONS: Our results suggest that HOTAIR can negatively regulate the expression of PPARα and that the combination of fenofibrate and si-HOTAIR treatment can significantly inhibit the progression of gliomas. This introduces new ideas for the treatment of gliomas.


Asunto(s)
Neoplasias Encefálicas/tratamiento farmacológico , Fenofibrato/farmacología , Glioma/tratamiento farmacológico , ARN Largo no Codificante/antagonistas & inhibidores , ARN Interferente Pequeño/farmacología , Adulto , Anciano , Animales , Encéfalo/patología , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Secuenciación de Inmunoprecipitación de Cromatina , Femenino , Fenofibrato/uso terapéutico , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glioma/diagnóstico , Glioma/genética , Glioma/patología , Humanos , Masculino , Ratones , Persona de Mediana Edad , Clasificación del Tumor , PPAR alfa/genética , ARN Largo no Codificante/genética , ARN Interferente Pequeño/uso terapéutico , Técnicas Estereotáxicas , Activación Transcripcional/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
8.
Regen Med ; 16(4): 373-390, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33787319

RESUMEN

Numerous individuals suffer from impaired wound healing, such as chronic ulcers, severe burns and immune disorders, resulting in both public health and economic burdens. Skin is the first line of defense and the largest organ of the human body, however, an incomplete understanding of underlying cellular and molecular mechanisms of dermal repair leads to a lack of effective therapy for healing impaired wounds. There are strong clinical and social needs for improved therapeutic approaches to enhance endogenous tissue repair and regenerative capacity. The purpose of this review is to illuminate the cellular and molecular aspects of the healing process and highlight potential therapeutic strategies to accelerate translational research and the development of clinical therapies in dermal wounds.


Asunto(s)
Quemaduras , Cicatrización de Heridas , Humanos , Piel
9.
Int J Immunogenet ; 46(6): 451-458, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31342644

RESUMEN

DNA mismatch repair (MMR) plays a critical role in the maintenance of genetic integrity. The failure of MMR in sperm DNA was found in male infertility. However, its aetiology in idiopathic male infertility (IMI) remains unknown. The present study was to investigate whether the four SNPs (rs26279 in MSH3, rs1800734 and rs4647269 in MLH1 and rs175080 in MLH3) in MMR genes were associated with IMI or not. The interactions of the SNPs were also performed to clarify its genetic aetiology. In the present study, 209 clinically diagnosed IMI men and 201 fertile men were recruited. Four SNPs were genotyped by DNA sequencing. It was the first time to investigate the association between rs26279 in MSH3 and IMI. The genotype frequency distribution of rs26279 (A>G) in MSH3 was found to be significantly different between IMI and control (p < 0.05), as well as azoospermia. The rs1800734 and rs4647269 in MLH1 were found to be significantly different between severe oligozoospermia and control groups (p < 0.05). However, rs175080 in MLH3 was not significantly different between IMI and control (p > 0.05). Multifactor dimensionality reduction (MDR) for detecting interactions showed that there were no interactions among the four SNPs on IMI.


Asunto(s)
Infertilidad Masculina/genética , Homólogo 1 de la Proteína MutL/genética , Proteínas MutL/genética , Proteína 3 Homóloga de MutS/genética , Polimorfismo de Nucleótido Simple , Alelos , Estudios de Casos y Controles , China , Daño del ADN , Reparación de la Incompatibilidad de ADN , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , Masculino
10.
Curr Med Sci ; 38(5): 809-817, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30594980

RESUMEN

Osteosarcoma is the most common primary malignant bone tumor in childhood, and it maintains a high level of recurrence. Matrix metalloproteinase-1 (MMP-1) was found to contribute to cancer progression. The present study was to investigate the in vitro effects of MMP-1 over-expression on the proliferation, invasion, metastasis and stem-like properties of osteosarcoma MG-63 cells. The MG-63 cells were cultured and had a full length MMP-1 cDNA inserted by the lentiviral vector (MG-63MMP-1+). MG-63 negative control and MG-63 blank control groups were established as well. MMP-1 expression was detected in MG-63MMP-1+, MG-63 negative control and MG-63 blank control cells using qPCR, Western blotting and immunofluorescence after 24 h of culture. The cell proliferation assay was performed with a camera attached to a bioreactor, which was programmed to photograph five regions of each well every 10 min over a period of 48 h. The cell invasion assay was conducted with Matrigel to assess the invasive potential of MG-63 cells over 24 h, the qPCR analysis to measure stem cell markers, including Oct4, Sox-2, Nanog, and Pax-7, and Western blot analysis to detect invasive and metastatic potential markers TIMP-1, VEGF and BMP2/4, after 24 h of culture. Immunofluorescence was used to investigate the presence of the stem cell marker Pax-7 after 24-h culture. The results showed that over-expression of MMP-1 after transfection could significantly increase tumor cell proliferation and invasion (P<0.05, MG-63MMP-1+versus controls). Pax-7 was highly expressed in MG-63MMP-1+ cells, with no significant changes of Oct-4, Sox-2, and Nanog observed (P<0.05). MG-63MMP-1+ cells showed higher expression of VEGF and BMP 2/4 proteins and lower expression of TIMP-1 protein than controls (P<0.05). It was concluded that MMP-1 over-expression in MG-63 cells contributed to the proliferation, invasion, metastasis and stem-like properties of osteosarcoma cells. Future studies should focus on in vivo effects of MMP-1 over-expression and the application of MMP-1 and Pax-7 inhibition in vivo to osteosarcoma therapies.


Asunto(s)
Neoplasias Óseas/metabolismo , Metaloproteinasa 1 de la Matriz/metabolismo , Osteosarcoma/metabolismo , Biomarcadores de Tumor/metabolismo , Línea Celular Tumoral , Proliferación Celular/fisiología , Humanos , Invasividad Neoplásica/patología , Osteosarcoma/patología , Inhibidor Tisular de Metaloproteinasa-1/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo
11.
Int J Nanomedicine ; 12: 6617-6632, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28924346

RESUMEN

The aim of the present work was to investigate the synergistic effect between toll-like receptor (TLR) 3 ligand polyinosinic:polycytidylic acid (pI:C) and TLR5 ligand flagellin (FLN) on immune responses induced by nasally delivered hepatitis B virus surface antigen (HBsAg). Mannan and chitosan oligosaccharide-modified, pH-responsive poly(lactic-co-glycolic acid) (MC-PLGA) microparticles (MPs) containing HBsAg, FLN, pI:C or both ligands were prepared with a double-emulsion method. In vitro uptake experiments show that cellular uptake of MC-PLGA MPs by macrophages was through energy-dependent, receptor-mediated endocytosis mechanism. After uptake of MPs by macrophages, MC-PLGA MPs existed both in the endo-some and in the cytoplasm. FLN and pI:C in solution or MP formulation could synergize to activate macrophages and induce higher pro-inflammatory cytokines interleukin (IL)-6, IL-12, interferon-γ and anti-inflammatory cytokines IL-10 compared to single TLR ligand (P<0.05). In vivo immunogenicity studies indicated that co-delivery of FLN and pI:C within MC-PLGA MPs synergistically induced higher serum anti-HBsAg IgG levels and Th1 cytokine levels compared with MC-PLGA MPs encapsulated single TLR ligand plus MPs encapsulated HBsAg (P<0.05). These results suggest that synergic TLR3 and TLR5 stimulation might be a promising novel tool for nasally delivered HBsAg.


Asunto(s)
Portadores de Fármacos/química , Flagelina/administración & dosificación , Antígenos de Superficie de la Hepatitis B/administración & dosificación , Poli I-C/administración & dosificación , Administración Intranasal , Animales , Quitosano/química , Portadores de Fármacos/administración & dosificación , Sinergismo Farmacológico , Femenino , Interferón gamma/metabolismo , Interleucina-10/metabolismo , Interleucina-12/metabolismo , Ácido Láctico/química , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Macrófagos/metabolismo , Microesferas , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Ratas Sprague-Dawley
12.
Sci Rep ; 7(1): 1177, 2017 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-28446779

RESUMEN

Mammalian skeletal muscles contain a number of heterogeneous cell populations. Our previous study characterized a unique population of myogenic lineage stem cells that can be isolated from adult mammalian skeletal muscles upon injury. These injury-induced muscle-derived stem cell-like cells (iMuSCs) displayed a multipotent state with sensitiveness and strong migration abilities. Here, we report that these iMuSCs have the capability to form neurospheres that represent multiple neural phenotypes. The induced neuronal cells expressed various neuron-specific proteins, their mRNA expression during neuronal differentiation recapitulated embryonic neurogenesis, they generated action potentials, and they formed functional synapses in vitro. Furthermore, the transplantation of iMuSCs or their cell extracts into the muscles of mdx mice (i.e., a mouse model of Duchenne Muscular Dystrophy [DMD]) could restore the morphology of their previously damaged neuromuscular junctions (NMJs), suggesting that the beneficial effects of iMuSCs may not be restricted to cell restoration alone, but also due to their transient paracrine actions. The current study reveals the essential role of iMuSCs in the restoration of NMJs related to injuries and diseases.


Asunto(s)
Diferenciación Celular , Músculo Esquelético/citología , Neurogénesis , Neuronas/fisiología , Células Madre/fisiología , Animales , Modelos Animales de Enfermedad , Ratones Endogámicos mdx , Distrofia Muscular de Duchenne/terapia , Trasplante de Células Madre/métodos
13.
Eur J Pharm Biopharm ; 109: 24-34, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27569030

RESUMEN

In the present study, surface-functionalized, pH-responsive poly(lactic-co-glycolic acid) (PLGA) microparticles were investigated for nasal delivery of hepatitis B surface Antigen (HBsAg). pH-responsive PLGA, chitosan modified PLGA (CS-PLGA), mannan modified PLGA (MN-PLGA), mannan and chitosan co-modified PLGA (MN-CS-PLGA) microparticles were prepared utilizing a double-emulsion method. Antigen was released rapidly from four types of microparticles at pH5.0 and pH 6.0, but slowly released at pH 7.4. Mannan and chitosan surface modification enhanced intracellular microparticle uptake by macrophages. Following intracellular macrophage antigen uptake, antigen release occurred in three different patterns: fast release from PLGA and MN-PLGA microparticles in endosomes/lysosomes, slow release from CS-PLGA microparticles in cytoplasm and a combination of fast release and slow release patterns from MN-CS-PLGA microparticles. Furthermore, chitosan coating modification increased the residence time of CS-PLGA and MN-CS-PLGA microparticles in the nasal cavity. In vivo immunogenicity studies indicated that MN-CS-PLGA microparticles induced stronger humoral and cell-mediated immune responses compared with PLGA, MN-PLGA and CS-PLGA microparticles. These results suggest that surface modification of pH-responsive PLGA microparticles with mannan and chitosan is a promising tool for nasal delivery of HBsAg.


Asunto(s)
Quitosano/química , Portadores de Fármacos/química , Ácido Láctico/química , Mananos/química , Microesferas , Ácido Poliglicólico/química , Vacunas/administración & dosificación , Administración Intranasal , Animales , Antígenos/química , Sistemas de Liberación de Medicamentos , Emulsiones , Endosomas/química , Femenino , Glicoles , Antígenos de Superficie de la Hepatitis B/administración & dosificación , Concentración de Iones de Hidrógeno , Lisosomas/química , Macrófagos/química , Macrófagos/citología , Macrófagos Peritoneales/metabolismo , Ratones , Nanopartículas/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Ratas , Ratas Sprague-Dawley , Propiedades de Superficie
14.
Int J Pharm ; 511(1): 560-569, 2016 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-27457422

RESUMEN

In the present study, lyophilization was attempted to improve the long-term storage of CS/GP thermogelling systems for biopharmaceutical applications. After lyophilization, CS/α,ß-GP lyophilizate could not be dissolved in water, but some metal salts, such as NaCl, CaCl2, and MgCl2 surprisingly facilitated its dissolution. X-ray powder diffraction analysis suggested that calcium ions might preferentially form salts with α,ß-GP, inhibit the transfer of protons from CS to α,ß-GP, and then inhibit the aggregation of CS molecules during lyophilization. Comparison of the freshly prepared CS/α,ß-GP/salt solutions and the reconstituted solutions from lyophilizates showed that lyophilization clearly influenced the properties of reconstituted CS/α,ß-GP/salt solutions such as gelation time, viscosity, and pH. Furthermore, the reconstituted CS/α,ß-GP/CaCl2 solutions maintained thermogelling properties and formed hydrogels at 37°C within approximately 5min, but did not form hydrogels at 20°C and 4°C over 2 weeks. The model protein bovine serum albumin (BSA) was further incorporated into the CS/α,ß-GP/CaCl2 system. In vitro release experiments showed the sustained release of BSA from CS/α,ß-GP/CaCl2 hydrogels in a pH-sensitive manner, demonstrating that CS/α,ß-GP/CaCl2 may be useful as an in situ gel-forming system.


Asunto(s)
Glicerofosfatos/química , Hidrogeles/química , Animales , Bovinos , Liberación de Fármacos/fisiología , Estabilidad de Medicamentos , Liofilización/métodos , Glicerofosfatos/metabolismo , Hidrogeles/metabolismo , Sales (Química) , Albúmina Sérica Bovina , Difracción de Rayos X
15.
Mol Med ; 21(1): 959-968, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26736177

RESUMEN

Extensively burned patients often suffer from sepsis, a complication that enhances postburn hypermetabolism and contributes to increased incidence of multiple organ failure, morbidity and mortality. Despite the clinical importance of burn sepsis, the molecular and cellular mechanisms of such infection-related metabolic derangements and organ dysfunction are still largely unknown. We recently found that upon endoplasmic reticulum (ER) stress, the white adipose tissue (WAT) interacts with the liver via inflammatory and metabolic signals leading to profound hepatic alterations, including hepatocyte apoptosis and hepatic fatty infiltration. We therefore hypothesized that burn plus infection causes an increase in lipolysis of WAT after major burn, partially through induction of ER stress, contributing to hyperlipidemia and profound hepatic lipid infiltration. We used a two-hit rat model of 60% total body surface area scald burn, followed by intraperitoneal (IP) injection of Pseudomonas Aeruginosa-derived lipopolysaccharide (LPS) 3 d postburn. One day later, animals were euthanized and liver and epididymal WAT (EWAT) samples were collected for gene expression, protein analysis and histological study of inflammasome activation, ER stress, apoptosis and lipid metabolism. Our results showed that burn plus LPS profoundly increased lipolysis in WAT associated with significantly increased hepatic lipid infiltration. Burn plus LPS augmented ER stress by upregulating CHOP and activating ATF6, inducing NLRP3 inflammasome activation and leading to increased apoptosis and lipolysis in WAT with a distinct enzymatic mechanism related to inhibition of AMPK signaling. In conclusion, burn sepsis causes profound alterations in WAT and liver that are associated with changes in organ function and structure.

16.
World J Stem Cells ; 7(1): 1-10, 2015 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-25621101

RESUMEN

Alternative splicing (AS) is an essential mechanism in post-transcriptional regulation and leads to protein diversity. It has been shown that AS is prevalent in metazoan genomes, and the splicing pattern is dynamically regulated in different tissues and cell types, including embryonic stem cells. These observations suggest that AS may play critical roles in stem cell biology. Since embryonic stem cells and induced pluripotent stem cells have the ability to give rise to all types of cells and tissues, they hold the promise of future cell-based therapy. Many efforts have been devoted to understanding the mechanisms underlying stem cell self-renewal and differentiation. However, most of the studies focused on the expression of a core set of transcription factors and regulatory RNAs. The role of AS in stem cell differentiation was not clear. Recent advances in high-throughput technologies have allowed the profiling of dynamic splicing patterns and cis-motifs that are responsible for AS at a genome-wide scale, and provided novel insights in a number of studies. In this review, we discuss some recent findings involving AS and stem cells. An emerging picture from these findings is that AS is integrated in the transcriptional and post-transcriptional networks and together they control pluripotency maintenance and differentiation of stem cells.

17.
Cell Stress Chaperones ; 20(2): 321-31, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25387796

RESUMEN

Microglia play an important role in neuronal protection and damage. However, the molecular and cellular relationship between microglia and neurons is unclear. We carried out a prospective study to detect that activation of BV2 microglia induced PC12 cell apoptosis in vitro through the TLR4/adapter protein myeloid differentiation factor 88 (MyD88)/nuclear factor-κB (NF-κB) signaling pathway. BV2 microglia were treated with different concentrations of LPS for 24 h. Western blot was utilized to detect the expression of TLR4 and the downstream signaling pathway. The level of inflammatory mediator was quantified using a specific ELISA kit. The supernatant of 10 µg/ml LPS-treated BV2 cells was used as conditioned medium (CM). PC12 cells were co-culture with CM for 24 h. Cell viability was determined by MTT assay and cell apoptosis was tested by flow cytometry. BV2 microglia were treated with 10, 20, or 30 µg/ml LPS for 24 h. The expression of TLR4, MyD88, and NF-κB significantly increased. When PC12 cells were co-cultured with CM for 24 h, cell viability decreased. CM up-regulated the Bax level and down-regulated the Bcl-2 protein level in PC12 cells. PC12 cells pretreated with interleukin-1 receptor antagonist (IL-1RA) for 30 min, significantly alleviated CM-induced PC12 cell apoptosis. These results suggest that BV2 microglia activated by LPS triggered TLR4/MyD88/NF-κB signaling pathway that induced the release of IL-1ß and could participate in the PC12 cells injury.


Asunto(s)
Apoptosis/efectos de los fármacos , Lipopolisacáridos/toxicidad , Receptor Toll-Like 4/metabolismo , Animales , Línea Celular , Medios de Cultivo Condicionados/farmacología , Regulación hacia Abajo/efectos de los fármacos , Proteínas I-kappa B/metabolismo , Interleucina-1beta/metabolismo , Microglía/citología , Microglía/efectos de los fármacos , Microglía/metabolismo , Factor 88 de Diferenciación Mieloide/metabolismo , FN-kappa B/metabolismo , Células PC12 , Polimixina B/farmacología , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Ratas , Transducción de Señal/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacos , Proteína X Asociada a bcl-2/metabolismo
18.
Shock ; 41(2): 138-44, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24434416

RESUMEN

Extensively burned patients often suffer from sepsis (especially caused by Pseudomonas aeruginosa), which may prolong metabolic derangement, contribute to multiple organ failure, and increase mortality. The molecular and cellular mechanisms of such infection-related metabolic derangement and organ dysfunction are unclear. We have previously shown that severely burned patients have significant and persisting hepatic endoplasmic reticulum (ER) stress. We hypothesized that ER stress and the unfolded protein response correlate with NOD-like receptor, pyrin domain containing 3 (NLRP3) inflammasome activation in burn. These may trigger profound metabolic changes in the liver, which form the pathological basis of liver damage and liver dysfunction after burn injury. A two-hit rat model was established by a 60% total body surface area scald burn and intraperitoneal injection of P. aeruginosa-derived lipopolysaccharide (LPS) 3 days after burn. One day later, animals were killed, and liver tissue samples were collected for gene expression and protein analysis of NLRP3 inflammasome activation, ER stress, and glucose and lipid metabolism. Liver damage was assessed by plasma markers (alanine aminotransferase and aspartate aminotransferase) and liver immunohistochemical analysis. Our results showed that burn injury and LPS injection induced inflammasome activation in liver and augmented hepatic ER stress and liver damage. Although there was an increased metabolic demand after burn, hepatic NLRP3 inflammasome activation corresponded to inhibition of PGC-1α (peroxisome proliferator-activated receptor γ-coactivator 1α) and its upstream regulators protein kinase A catalyst unit, AMP-activated protein kinase α, and sirtuin-1 may provide a mechanism for the enhanced metabolic derangement after major burn injury plus sepsis. In conclusion, burn + LPS augments inflammasome activation and ER stress in liver, which in turn contribute to postburn metabolic derangement.


Asunto(s)
Quemaduras/fisiopatología , Estrés del Retículo Endoplásmico/fisiología , Inflamasomas/fisiología , Lipopolisacáridos/toxicidad , Hepatopatías/fisiopatología , Hígado/metabolismo , Receptores Citoplasmáticos y Nucleares/fisiología , Factores de Transcripción/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Proteínas Portadoras , Masculino , Proteína con Dominio Pirina 3 de la Familia NLR , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma , Pseudomonas aeruginosa/química , Ratas , Sirtuina 1/antagonistas & inhibidores , Sirtuina 1/metabolismo
19.
Eur J Neurosci ; 39(4): 531-47, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24236816

RESUMEN

Dlx1, a member of the homeobox domain transcriptional factors, is expressed in a subset of interneurons and is involved in their differentiation. To understand the roles of Dlx1 in dendritic and postsynaptic differentiation, we manipulated Dlx1 expression in both excitatory pyramidal neurons and inhibitory interneurons in hippocampal culture. Exogenous expression of Dlx1 in pyramidal neurons, which lack endogenous Dlx1, resulted in reduced complexity of dendritic arborization. This effect was dependent on the DNA-binding motif of Dlx1. Dlx1 overexpression also induced prominent reduction of spine density, but with mild suppression in the formation of postsynaptic densities. To confirm the roles of endogenous Dlx1, we knocked down Dlx1 in interneurons and found enhanced dendritic growth. By manipulating the expression of possible downstream effectors of Dlx1, neuropilin-2 and p21-activated kinase 3, we provided evidence for the involvement of these two signaling molecules in Dlx1-dependent regulation of dendritic differentiation. Our experimental data support the idea that Dlx1 expression in developing interneurons specifically suppresses two important downstream regulators, leading to the characteristic morphology of Dlx1-expressing interneurons with less branched dendrites and few dendritic spines.


Asunto(s)
Dendritas/metabolismo , Proteínas de Homeodominio/metabolismo , Neurogénesis , Neuropilina-2/metabolismo , Densidad Postsináptica/metabolismo , Factores de Transcripción/metabolismo , Quinasas p21 Activadas/metabolismo , Animales , Células Cultivadas , Dendritas/fisiología , Hipocampo/citología , Hipocampo/crecimiento & desarrollo , Proteínas de Homeodominio/genética , Interneuronas/citología , Interneuronas/metabolismo , Ratones , Ratones Endogámicos ICR , Neuropilina-2/genética , Células Piramidales/citología , Células Piramidales/metabolismo , Factores de Transcripción/genética , Quinasas p21 Activadas/genética
20.
J. physiol. biochem ; 69(4): 707-718, dic. 2013.
Artículo en Inglés | IBECS | ID: ibc-121630

RESUMEN

Propofol exhibits neuroprotective effects against hypoxic–ischemic brain injury, but the underlying mechanisms are still not clear. Toll-like receptor 4 (TLR4) plays a considerable role in the induction of innate immune and inflammatory responses. The purposes of this study are to investigate the effect of propofol on the oxygen and glucose deprivation (OGD)/reoxygenation (OGD/R) BV2 microglia and to explore the role of TLR4/myeloid differentiation protein 88 (MyD88)/nuclear factor-kappa B (NF-KappaB) pathway in the neuroprotective effects of propofol. BV2 microglia were placed into an airtight chamber and in glucose-free medium for OGD/reoxygenation. Cell viability was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide assay. TLR4 and its downstream signaling molecules, MyD88 and NF-KappaB expressions were detected by Western blotting. Level of tumor necrosis factor alpha (TNF-Alpha) in culture medium was determined with enzyme-linked immunosorbent assay. BV2 microglia apoptosis was determined by flow cytometry. We found that pretreatment with propofol significantly alleviated the hypoxic injury in BV2 microglia. Propofol inhibited upregulation of TLR4, MyD88, and NF-KappaB expressions in BV2 microglia exposed to OGD/reoxygenation. Propofol pretreatment also significantly reduced the production of TNF-Alpha and apoptosis in OGD/reoxygenation BV2 microglia. The results indicated that TLR4 and its downstream MyD88-dependent signaling pathway contributed to neuroprotection of propofol to microglia exposed to OGD/reoxygenation


Asunto(s)
Animales , Ratas , Propofol/farmacocinética , Microglía , Hipoxia-Isquemia Encefálica/tratamiento farmacológico , Receptor Toll-Like 4/fisiología , Sustancias Protectoras/farmacocinética , Modelos Animales de Enfermedad , Inmunidad Innata/fisiología , Fármacos Neuroprotectores/farmacocinética
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