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1.
Angew Chem Int Ed Engl ; : e202414777, 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39325543

RESUMEN

Solid polymer electrolytes hold promise for addressing key challenges in rechargeable zinc batteries (ZBs) utilizing aqueous electrolytes. However, achieving simultaneous high ionic conductivity, excellent mechanical strength, and a high cation transference number while effectively suppressing Zn dendrites remains challenging. Herein, we design a novel polymer-in-salt solid electrolyte (PISSE) composed of polyacrylonitrile (PAN), zinc chloride (ZnCl2), and niobium pentoxide with oxygen vacancies (Nb2O5-x) with high ionic conductivity. PAN polymer matrix provides the electrolyte good mechanical properties and solubility of Zn salt. The high concentration of ZnCl2 effectively decouples the Zn2+ from polymer chain segments and provides more ionic conduction amorphous region. Moreover, incorporating Nb2O5-x filler accelerates Zn2+ desolvation by anchoring (ZnxCly)2x-y clusters and enhances the system's mechanical properties, achieving a superior Zn2+ transference number (~0.93) and interfacial stability. Consequently, the optimized PISSE demonstrates exceptional stability during prolonged cycling periods, wide temperature range operation (-40 ℃ to 60 ℃), remarkable flexibility, and compatibility with diverse electrode materials. This study provides valuable insights into the design of solid-state electrolytes based on ZBs and elucidates their multifunctional prospects.

2.
ChemSusChem ; 17(19): e202400526, 2024 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-38679575

RESUMEN

Layered vanadium-based oxides have emerged as highly promising candidates for aqueous zinc-ion batteries (AZIBs) due to their open-framework layer structure and high theoretical capacity among the diverse cathode materials investigated. However, the susceptibility to structural collapse during charge-discharge cycling severely hampers their advancement. Herein, we propose an effective strategy to enhance the cycling stability of vanadium oxides. Initially, the structural integrity of the host material is significantly reinforced by incorporating bi-cations Na+ and NH4 + as "pillars" between the V2O5 layers (NaNVO). Subsequently, surface coating with polyaniline (PA) is employed to further improve the conductivity of the active material. As anticipated, the assembled Zn//NaNVO@PA cell exhibits a remarkable discharge capacity of 492 mAh g-1 at 0.1 A g-1 and exceptional capacity retention up to 89.2 % after 1000 cycles at a current density of 5 A g-1. Moreover, a series of in-situ and ex-situ characterization techniques were utilized to investigate both Zn ions insertion/extraction storage mechanism and the contribution of polyaniline protonation process towards enhancing capacity.

3.
BMC Complement Altern Med ; 15: 240, 2015 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-26183217

RESUMEN

BACKGROUD: The Piper laetispicum C.DC. (Piperaceae) is a traditionally used herb in China for invigorating circulation and reducing stasis, detumescence and analgesia, which is distributed in the southern part of China and the southeastern part of Asia. Previous studies demonstrated that the ethyl acetate extract (EAE-P) of P. laetispicum possesses a significant antidepressant-like effect at doses higher than 60 mg/kg in Kunming (KM) mice, and this effect was not due to an increase in locomotive activity. METHODS: To research this mechanism, in the present study, the chronic unpredictable mild stress (CUMS) model in Sprague-Dawley rats was used to further elucidate behavioral changes and corresponding changes in inflammatory cytokines (TNF-α, IL-6, IL-10), apoptosis cytokines (P53, Bax, Bcl2, caspase-3) and neurotrophin (BDNF) in the hippocampus of EAE-P treatment animals. RESULTS AND CONCLUSIONS: The results suggest that EAE-P is beneficial to the behavioral outcome of the CUMS model animals, and decreased amounts of inflammatory cytokine IL-6 contributed to the antidepressant-like activation of EAE-P in every dosage group (15, 30, 60 mg/kg). In the low dosage group, down-regulated apoptosis cytokine p53 is associated with EAE-P effect, but it is inflammatory cytokine TNF-α that is related to the effect of EAE-P in the high dosage group. Meanwhile, the P53-dependent antiapoptotic effect of EAE-P may not be through Bcl-2 and Bax modulation. Furthermore, EAE-P showed up-regulated expression of brain-derived neurotrophic factor (BDNF) mRNA and down-regulated apoptosis cytokine caspase-3 mRNA, which was the same change tendency as with Fluoxetine.


Asunto(s)
Conducta Animal/efectos de los fármacos , Citocinas/metabolismo , Hipocampo/efectos de los fármacos , Factores de Crecimiento Nervioso/metabolismo , Piper/química , Extractos Vegetales/farmacología , Estrés Psicológico/metabolismo , Animales , Ratas , Ratas Sprague-Dawley
4.
J Neuroinflammation ; 11: 147, 2014 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-25134526

RESUMEN

BACKGROUND: Neuroinflammation mediated by overactivated microglia plays a key role in many neurodegenerative diseases, including Alzheimer's disease (AD). In this study, we investigated for the first time the anti-neuroinflammatory effects and possible mechanisms of SCM-198 (an alkaloid extracted from Herbaleonuri), which was previously found highly cardioprotective, both in vitro and in vivo. METHODS: For in vitro experiments, lipopolysaccharide (LPS) or ß-amyloid(1-40) (Aß(1-40)) was applied to induce microglial overactivation. Proinflammatory mediators were measured and activations of NF-κB and mitogen-activated protein kinases' (MAPKs) pathways were investigated. Further protective effect of SCM-198 was evaluated in microglia-neuron co-culture assay and Sprague-Dawley (SD) rats intrahippocampally-injected with Aß(1-40). RESULTS: SCM-198 reduced expressions of nitric oxide (NO), TNF-α, IL-1ß and IL-6 possibly via, at least partially, inhibiting c-Jun N-terminal kinase (JNK) and NF-κB signaling pathways in microglia. Co-culture assay showed that activated microglia pretreated with SCM-198 led to less neuron loss and decreased phosphorylation of tau and extracellular signal-regulated kinase (ERK) in neurons. Besides, SCM-198 also directly protected against Aß(1-40)-induced neuronal death and lactate dehydrogenase (LDH) release in primary cortical neurons. For in vivo studies, SCM-198 significantly enhanced cognitive performances of rats 12 days after intrahippocampal injections of aged Aß(1-40) peptides in the Morris water maze (MWM), accompanied by less hippocampal microglial activation, decreased synaptophysin loss and phosphorylation of ERK and tau. Co-administration of donepezil and SCM-198 resulted in a slight cognitive improvement in SD rats 50 days after intrahippocampal injections of aged Aß(1-40) peptides as compared to only donepezil or SCM-198 treated group. CONCLUSIONS: Our findings are the first to report that SCM-198 has considerable anti-neuroinflammatory effects on inhibiting microglial overactivation and might become a new potential drug candidate for AD therapy in the future.


Asunto(s)
Trastornos del Conocimiento/tratamiento farmacológico , Ácido Gálico/análogos & derivados , MAP Quinasa Quinasa 4/metabolismo , Microglía/metabolismo , FN-kappa B/metabolismo , Fármacos Neuroprotectores/uso terapéutico , Transducción de Señal/efectos de los fármacos , Péptidos beta-Amiloides/toxicidad , Animales , Animales Recién Nacidos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Corteza Cerebral/citología , Técnicas de Cocultivo , Trastornos del Conocimiento/inducido químicamente , Citocinas/genética , Citocinas/metabolismo , Ácido Gálico/uso terapéutico , L-Lactato Deshidrogenasa/metabolismo , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Microglía/efectos de los fármacos , Neuronas/efectos de los fármacos , Fragmentos de Péptidos/toxicidad , Ratas , Ratas Sprague-Dawley
5.
Biomed Chromatogr ; 26(4): 518-23, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21882210

RESUMEN

Leonurine (SCM-198), an alkaloid from Herba Leonuri, has been suggested as a novel cardiovascular agent by pharmacology studies in preclinical stage. In present study, we report a simple, rapid and sensitive high-performance liquid chromatography-tandem mass spectrometry method (HPLC-MS/MS) for determination of leonurine in rat plasma. Leonurine and its internal standard (IS) n-benzoyl-l-arginine ethyl ester (BAEE) were extracted from plasma samples by one-step protein precipitation with perchloric acid. Chromatographic separation was performed on an Agilent Zorbax SB-C18 column (150 × 2.1 mm, 5 µm) using an isocratic elution with acetonitrile-ammonium acetate buffer (10 mm, pH 4.0; 25:75, v/v) as mobile phase at a flow rate of 0.2 mL/min. Analytes were detected by tandem mass spectrometry in positive electrospray ionization (ESI) mode using multiple reaction monitoring (MRM) with the transitions of m/z 312.3 → 181.1 for leonurine and m/z 307.2 → 104.6 for IS. The calibration curves were linear over the range of 4-256 ng/mL with a lower limit of quantitation (LLOQ) of 4 ng/mL. The intra- and inter-day assay precision (as relative standard deviation) were <15%, except which at LLOQ were <20%, with accuracy in the range 98.73-105.42%. The validated HPLC-MS/MS method was successfully applied to the pharmacokinetic study in rats following oral administration of leonurine.


Asunto(s)
Fármacos Cardiovasculares/sangre , Cromatografía Líquida de Alta Presión/métodos , Ácido Gálico/análogos & derivados , Espectrometría de Masas en Tándem/métodos , Animales , Arginina/análogos & derivados , Arginina/sangre , Calibración , Ácido Gálico/sangre , Leonurus/química , Límite de Detección , Masculino , Ratas , Ratas Sprague-Dawley
6.
Eur J Med Chem ; 46(9): 3996-4009, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21723646

RESUMEN

The design, synthesis and biological evaluation of novel Leonurine-cysteine analog conjugates 3,5-dimethoxy-4-(2-amino-3-prop-2-ynylsulfanyl-propionyl)-benzoic acid 4-guanidino-butyl ester (1a), 3,5-dimethoxy-4-(2-animo-3-allysulfanyl-propionyl)-benzoic acid 4-guanidino-butyl ester (1b) and 3,5-dimethoxy-4-(3-(2-chlorocarbonyl-ethyldisulfanyl)-propionyl)-benzoic acid 4-guanidino-butyl ester (2) were reported in this paper. We tested their effects on hypoxia-induced neonatal rat ventricular myocytes. Our data showed that all of them had cardioprotective effects. Both of 1a and 1b were able to modulate hydrogen sulfide production, and 1a possessed higher biological activity than 1b and 2, which indicated that there was positive correlation between conjugates and their precursors. Furthermore we illuminated that the cardioprotective mechanism of 1a were related to increase SOD and CAT activity, decrease MDA and ROS level, protect some cell organs and regulate apoptosis-associated genes and proteins expression (bcl-2 and bax) via the caspase-3 pathway in molecular level. These results indicated that 1a had the potential to be a new class of multifunctional anti-myocardial ischemia agent. Most importantly, these results provided us important clues for the further design and modification of this type of Leonurine-cysteine analog conjugates in future.


Asunto(s)
Cisteína/uso terapéutico , Ácido Gálico/análogos & derivados , Isquemia Miocárdica/tratamiento farmacológico , Animales , Animales Recién Nacidos , Western Blotting , Catalasa/metabolismo , Células Cultivadas , Cisteína/química , Cisteína/farmacología , Ácido Gálico/química , Ácido Gálico/farmacología , Ácido Gálico/uso terapéutico , Ventrículos Cardíacos/efectos de los fármacos , Ventrículos Cardíacos/enzimología , Ventrículos Cardíacos/metabolismo , Espectroscopía de Resonancia Magnética , Malondialdehído/metabolismo , Espectrometría de Masas , Reacción en Cadena de la Polimerasa/métodos , Ratas , Superóxido Dismutasa/metabolismo
7.
J Alzheimers Dis ; 24 Suppl 2: 173-82, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21441657

RESUMEN

For hundreds of years, hydrogen sulfide (H2S) has been known solely as a toxic gas with the smell of rotten eggs. Nevertheless, the notoriety of H2S as a toxic gas is experiencing a transformation, with an increasing amount of research showing that it regulates a range of physiological and pathological processes in mammals. Hence H2S is a physiologically important molecule and has been referred to as the third gaseous mediator alongside nitric oxide and carbon monoxide. This past decade has seen an exponential growth of scientific interest in the physiological and pathological significance of H2S. In particular, in the central nervous system, H2S facilitates long-term potentiation and regulates intracellular calcium concentration and pH level in brain cells. Interestingly, H2S may exert antioxidant, anti-apoptotic, and anti-inflammatory effects which are related to neurodegenerative disorders such as Alzheimer's disease (AD), Parkinson's disease (PD), and vascular dementia. Meanwhile, abnormal generation and metabolism of H2S are involved in most of these neurodegenerative disorders. This review presents current knowledge of H2S and its neuroprotective effects in neurodegenerative disorders, with a special emphasis on AD and PD. It is concluded that a H2S-modulated agent will be a new hope for neurodegenerative disorders including AD and PD.


Asunto(s)
Antioxidantes/uso terapéutico , Sulfuro de Hidrógeno/uso terapéutico , Enfermedades Neurodegenerativas/terapia , Animales , Antioxidantes/farmacología , Humanos , Sulfuro de Hidrógeno/farmacología , Modelos Biológicos
8.
J Cell Sci ; 121(Pt 24): 4029-36, 2008 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-19033383

RESUMEN

Aquaporin-4 (AQP4), a key molecule for maintaining water and ion homeostasis in the central nervous system, is expressed in adult neural stem cells (ANSCs) as well as astrocytes. However, little is known about the functions of AQP4 in the ANSCs in vitro. Here we show that AQP4 knockout inhibits the proliferation, survival, migration and neuronal differentiation of ANSCs derived from the subventricular zone of adult mice. Flow cytometric cell cycle analysis revealed that AQP4 knockout increased the basal apoptosis and induced a G2-M arrest in ANSCs. Using Fluo-3 Ca2+ imaging, we show that AQP4 knockout alters the spontaneous Ca2+ oscillations by frequency enhancement and amplitude suppression, and suppresses KCl-induced Ca2+ influx. AQP4 knockout downregulated the expression of connexin43 and the L-type voltage-gated Ca2+ channel CaV1.2 subtype in ANSCs. Together, these findings suggest that AQP4 plays a crucial role in regulating the proliferation, migration and differentiation of ANSCs, and this function of AQP4 is probably mediated by its action on intracellular Ca2+ dynamics.


Asunto(s)
Células Madre Adultas/citología , Acuaporina 4/fisiología , Canales de Calcio Tipo L/metabolismo , Calcio/metabolismo , Conexina 43/metabolismo , Neuronas/citología , Células Madre Adultas/metabolismo , Animales , Acuaporina 4/genética , Diferenciación Celular/fisiología , Movimiento Celular/fisiología , Proliferación Celular , Células Cultivadas , Ratones , Ratones Noqueados , Neuronas/metabolismo
9.
Neurosci Lett ; 439(3): 230-4, 2008 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-18524485

RESUMEN

ATP-sensitive potassium (K-ATP) channels have been demonstrated to play important roles in the brain. In the present study, Kir6.2 knockout (Kir6.2-/-) mice were used to examine the contribution of Kir6.2-containing K-ATP channels to the regulation of neurotransmitter release via in vivo microdialysis studies. The results showed that the extracellular levels of monoamine and amino acid neurotransmitters in Kir6.2-/- mouse striatum were similar to those in Kir6.2+/+ mice under basal conditions. After high K+ (100mM) perfusion, the extracellular levels of DA and amino acids were increased in both genotypes. These increases, however, were significantly lower in Kir6.2-/- mice than those in Kir6.2+/+ mice. Extracellular levels of 3,4-dihydroxyphenylacetic acid (DOPAC), a major metabolite of DA, were increased in Kir6.2-/- mice but decreased in Kir6.2+/+ mice in response to high K+ stimulus. The releases of 4-hydroxy-3-methoxy-phenylacetic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) were attenuated to a similar extent in both mouse genotypes. Taken together, this study provides direct in vivo evidence that Kir6.2-containing K-ATP channels play regulatory roles in neurotransmitter release in the striatum.


Asunto(s)
Cuerpo Estriado/metabolismo , Neurotransmisores/metabolismo , Canales de Potasio de Rectificación Interna/deficiencia , Ácido 3,4-Dihidroxifenilacético/metabolismo , Animales , Cuerpo Estriado/efectos de los fármacos , Dopamina/metabolismo , Líquido Extracelular/efectos de los fármacos , Líquido Extracelular/metabolismo , Ácido Homovanílico/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Microdiálisis/métodos , Cloruro de Potasio/farmacología
10.
Neurobiol Aging ; 29(8): 1226-36, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17353068

RESUMEN

Aquaporin 4 (AQP4) is a predominant water channel protein in mammalian brains, which is localized in the astrocyte plasma membrane. AQP4 has gained much attraction due to its involvement in the physiopathology of cerebral disorders including stroke, tumor, infection, hydrocephalus, epilepsy, and traumatic brain injury. But there is almost no evidence whether abnormal AQP4 levels are associated with degenerative diseases, such as Parkinson's disease (PD). In our studies, we established PD animal models by administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine to test the hypothesis that abnormal AQP4 expression is involved in the pathophysiology of this disease. We show that mutant mice lacking AQP4 were significantly more prone to MPTP-induced neurotoxicity than their wild-type littermates. Furthermore, after administration of MPTP, astroglial proliferation and GDNF protein synthesis were inhibited by AQP4 deficiency. This study demonstrates that AQP4 is important in the MPTP neurotoxic process and indicates that the therapeutic strategy targeted to astrocytic modulation with AQP4 may offer a great potential for the development of new treatment for PD.


Asunto(s)
1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/administración & dosificación , Acuaporina 4/metabolismo , Gliosis/inducido químicamente , Gliosis/diagnóstico , Trastornos Parkinsonianos/inducido químicamente , Trastornos Parkinsonianos/diagnóstico , Animales , Acuaporina 4/genética , Relación Dosis-Respuesta a Droga , Ratones , Ratones Noqueados , Ratones Transgénicos , Neurotoxinas/administración & dosificación
11.
J Neurochem ; 94(6): 1570-9, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16000145

RESUMEN

Mounting evidence reveals that ATP-sensitive potassium (K(ATP)) channel openers (KCOs) exert significant neuroprotection in vivo and in vitro in several models of Parkinson's disease (PD). However, the mechanisms are not well understood. In this study, we demonstrated that SH-SY5Y cells expressed mRNA and proteins for Kir6.1, Kir6.2, SUR1 and SUR2 subunits of K(ATP) channels. Moreover, our results showed that 1-methyl-4-phenyl-pyridinium ion (MPP+) induced up-regulation of mRNA for the Kir6.2 subunit and down-regulation of SUR1. It was further found that pretreatment with iptakalim, a novel K(ATP) channel opener, could attenuate increased extracellular glutamate level and decreased cell survival in SH-SY5Y cell culture after exposure to MPP+. Trans-pyrrolidine-2, 4-dicarboxylic acid (t-PDC), a glutamate transporter inhibitor, partially blocked the effect of iptakalim decreasing extracellular glutamate level. Additionally, iptakalim prevented MPP+-induced inhibition of glutamate uptake in primary cultured astrocytes. The beneficial effects of iptakalim on glutamate uptake of astrocytes were abolished by selective mitochondrial K(ATP) (mitoK(ATP)) channel blocker 5-HD. These results suggest (i) K(ATP) channel dysfunction may be involved in the mechanisms of MPP+-induced cytotoxicity and (ii) iptakalim may modulate glutamate transporters and subsequently alleviate the increase of extracellular glutamate levels induced by MPP+ through opening mitoK(ATP) channels, thereby protecting SH-SY5Y cells against MPP+-induced cytotoxicity.


Asunto(s)
1-Metil-4-fenilpiridinio/antagonistas & inhibidores , Citoprotección/efectos de los fármacos , Ácido Glutámico/metabolismo , Neuronas/efectos de los fármacos , Canales de Potasio de Rectificación Interna/antagonistas & inhibidores , Propilaminas/farmacología , 1-Metil-4-fenilpiridinio/toxicidad , Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Sistema de Transporte de Aminoácidos X-AG/antagonistas & inhibidores , Sistema de Transporte de Aminoácidos X-AG/metabolismo , Línea Celular Tumoral , Citoprotección/fisiología , Regulación hacia Abajo/efectos de los fármacos , Regulación hacia Abajo/fisiología , Líquido Extracelular/efectos de los fármacos , Líquido Extracelular/metabolismo , Humanos , Degeneración Nerviosa/inducido químicamente , Degeneración Nerviosa/tratamiento farmacológico , Degeneración Nerviosa/prevención & control , Neuronas/metabolismo , Fármacos Neuroprotectores/farmacología , Neurotoxinas/antagonistas & inhibidores , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/metabolismo , Enfermedad de Parkinson/fisiopatología , Bloqueadores de los Canales de Potasio/farmacología , Canales de Potasio/efectos de los fármacos , Canales de Potasio/genética , Canales de Potasio/metabolismo , Canales de Potasio de Rectificación Interna/genética , Canales de Potasio de Rectificación Interna/metabolismo , ARN Mensajero/efectos de los fármacos , ARN Mensajero/metabolismo , Receptores de Droga/genética , Receptores de Droga/metabolismo , Receptores de Sulfonilureas
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