Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 25
Filtrar
1.
Inorg Chem ; 63(14): 6305-6314, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38549559

RESUMEN

MXenes are a revolutionary class of two-dimensional materials that have been recently demonstrated to exhibit promising capability of electrocatalytic CO2 reduction reaction (CO2RR) in theory and experiment. In electrocatalytic reactions, the active phases, the mechanism, and the performance can be greatly influenced by electrochemical conditions such as applied electrode potential, pH, and electrolyte. Therefore, in this first-principles study, the stable surface structures of three typical MXenes (V2C, Mo2C, and Ti3C2) with variation of electrocatalytic conditions were determined by the Pourbaix phase diagrams. Additionally, the reaction mechanism for CO2RR toward C1 products was investigated based on the thermal dynamically stable phases. The computation revealed that surfaces of all three MXenes are dominated by H* termination throughout the practical CO2RR electrochemical condition ranges. Meanwhile, the bicarbonate ions, which serve as the major electrolyte in CO2RR, show thermal dynamic unfavorability to adsorb on the surfaces. Among the three types of MXenes, V2CH exhibits higher activity in generating CO and HCOOH through the CO2RR, while Mo2CH exhibits higher activity in producing HCHO, CH3OH, and CH4. This comprehensive study provides crucial insights into the mechanism of electrocatalytic CO2RR on MXenes under realistic electrochemical conditions.

2.
J Chem Phys ; 161(1)2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-38953451

RESUMEN

Inspired by biological channels, achieving precise separation of ion/water and ion/ion requires finely tuned pore sizes at molecular dimensions and deliberate exposure of charged groups. Covalent organic frameworks (COFs), a class of porous crystalline materials, offer well-defined nanoscale pores and diverse structures, making them excellent candidates for nanofluidic channels that facilitate ion and water transport. In this study, we perform molecular simulations to investigate the structure and kinetics of water and ions confined within the typical COFs with varied exposure of charged groups. The COFs exhibit vertically arrayed nanochannels, enabling diffusion coefficients of water molecules within COFs to remain within the same order of magnitude as in the bulk. The motion of water molecules manifests in two distinct modes, creating a mobile hydration layer around acid groups. The ion diffusion within COFs displays a notable disparity between monovalent (M+) and divalent (M2+) cations. As a result, the selectivity of M+/M2+ can exceed 100, while differentiation among M+ is less pronounced. In addition, our simulations indicate a high rejection (R > 98%) in COFs, indicating their potential as ideal materials for desalination. The chemical flexibility of COFs indicates that would hold significant promise as candidates for advanced artificial ion channels and separation membranes.

3.
Small ; 17(21): e2100372, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33864356

RESUMEN

Electrocatalysts for efficient production of ammonia from nitrogen reduction reaction (NRR) under ambient conditions are attracted growing interest in recent years, which demonstrate a great potential to replace the Haber-Bosch method which suffers the problems of the huge energy consumption and massive CO2 production. In this work, a novel electrocatalyst of Au25 -Cys-M is fabricated for NRR under ambient conditions, with transition metal ions (e.g., Mo6+ , Fe3+ , Co2+ , Ni2+ ) atomically decorated on Au25 nanoclusters via thiol bridging. The Au25 -Cys-Mo catalyst exhibits the highest Faradaic efficiency (26.5%) and NH3 yield (34.5 µg h-1  mgcat -1 ) in 0.1 m HCl solution. X-ray photoelectron spectroscopy analysis and high angle annular dark field image-scanning transmission electron microscopy characterization reveal that the electronic structure of Mo is optimized by forming the structure of Au-S-Mo and Mo acts as active sites for activating the nitrogen to promote the electrochemical production of ammonia. This work provides a new insight into the precise fabrication of efficient NRR electrocatalysts.

4.
J Cell Mol Med ; 23(11): 7651-7663, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31565849

RESUMEN

Diabetic cardiomyopathy is characterized by diabetes-induced myocardial abnormalities, accompanied by inflammatory response and alterations in inflammation-related signalling pathways. Kirenol, isolated from Herba Siegesbeckiae, has potent anti-inflammatory properties. In this study, we aimed to investigate the cardioprotective effect of kirenol against DCM and underlying the potential mechanisms in a type 2 diabetes mellitus model. Kirenol treatment significantly decreased high glucose-induced cardiofibroblasts proliferation and increased the cardiomyocytes viability, prevented the loss of mitochondrial membrane potential and further attenuated cardiomyocytes apoptosis, accompanied by a reduction in apoptosis-related protein expression. Kirenol gavage could affect the expression of pro-inflammatory cytokines in a dose-dependent manner but not lower lipid profiles, and only decrease fasting plasma glucose, fasting plasma insulin and mean HbA1c levels in high-dose kirenol-treated group at some time-points. Left ventricular dysfunction, hypertrophy, fibrosis and cell apoptosis, as structural and functional abnormalities, were ameliorated by kirenol administration. Moreover, in diabetic hearts, oral kirenol significantly attenuated activation of mitogen-activated protein kinase subfamily and nuclear translocation of NF-κB and Smad2/3 and decreased phosphorylation of IκBα and both fibrosis-related and apoptosis-related proteins. In an Electrophoretic mobility shift assay, the binding activities of NF-κB, Smad3/4, SP1 and AP-1 in the nucleus of diabetic myocardium were significantly down-regulated by kirenol treatment. Additionally, high dose significantly enhanced myocardial Akt phosphorylation without intraperitoneal injection of insulin. Kirenol may have potent cardioprotective effects on treating for the established diabetic cardiomyopathy, which involves the inhibition of inflammation and fibrosis-related signalling pathways and is independent of lowering hyperglycaemia, hyperinsulinemia and lipid profiles.


Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Cardiomiopatías Diabéticas/tratamiento farmacológico , Diterpenos/uso terapéutico , Inflamación/tratamiento farmacológico , Animales , Biomarcadores/metabolismo , Glucemia/metabolismo , Peso Corporal/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Colágeno/biosíntesis , Citocinas/sangre , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/patología , Diabetes Mellitus Experimental/fisiopatología , Cardiomiopatías Diabéticas/sangre , Cardiomiopatías Diabéticas/patología , Cardiomiopatías Diabéticas/fisiopatología , Diterpenos/administración & dosificación , Diterpenos/química , Diterpenos/farmacología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Fibroblastos/patología , Fibrosis , Glucosa/toxicidad , Inflamación/sangre , Inflamación/complicaciones , Masculino , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Miocardio/metabolismo , Miocardio/patología , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Inhibidor NF-kappaB alfa/metabolismo , Fosforilación/efectos de los fármacos , Unión Proteica/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Proteínas Smad/metabolismo , Remodelación Ventricular/efectos de los fármacos
5.
BMC Complement Altern Med ; 18(1): 46, 2018 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-29391009

RESUMEN

BACKGROUND: Guang-Pheretima, which is originated from Pheretima aspergillum, has been documented in academic Chinese herbal studies for nearly 2000 years for its prominent treating effects of various inflammatory diseases such as asthma, cough and fever. However, the anti-inflammatory activity and mechanism of Guang-Pheretima has been rarely reported. Hence, we investigated the inhibitory effect and the underlying mechanism of Guang-Pheretima aqueous extracts on inflammatory response in RAW 264.7 cells. METHOD: RAW 264.7 macrophages were pretreated with various concentrations of Guang-Pheretima decoction (GPD) or protein-free Guang-Pheretima decoction (PF-GPD) and subsequently stimulated with lipopolysaccharide (LPS) to trigger the inflammatory response. Productions of nitric oxide (NO) were determined by Griess reaction, and prostaglandin E2 (PGE2), tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß, IL-6 were measured by enzyme-linked immunosorbent assays (ELISA). The protein expressions and messenger ribonucleic acid (mRNA) amounts of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 were analyzed by Western Blot and Real-Time polymerase chain reaction (PCR), respectively. Finally, the translocation of nuclear factor (NF)-κB was observed by Western Blot. RESULTS: GPD of the experimental concentrations showed no anti-inflammatory activity. In contrast, PF-GPD at concentrations of 40-320 µg/mL significantly inhibited NF-κB activation and reduced the production of inflammatory mediators, such as NO, PGE2, TNF-α, as well as the related key synthases including iNOS and COX-2. Moreover, PF-GPD markedly suppressed the release of inflammatory cytokines, such as IL-1ß and IL-6. CONCLUSION: These results demonstrate the excellent anti-inflammatory properties of PF-GPD, and suggest that Guang-Pheretima may be used to treat and prevent certain inflammatory diseases.


Asunto(s)
Antiinflamatorios/farmacología , Productos Biológicos/farmacología , Macrófagos/efectos de los fármacos , Animales , Antiinflamatorios/química , Productos Biológicos/química , Supervivencia Celular/efectos de los fármacos , Ciclooxigenasa 2/metabolismo , Citocinas/análisis , Citocinas/metabolismo , Lipopolisacáridos/toxicidad , Macrófagos/metabolismo , Ratones , Oligoquetos/química , Células RAW 264.7
6.
Angew Chem Int Ed Engl ; 56(27): 7769-7773, 2017 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-28467678

RESUMEN

Cobalt-based nanomaterials have been intensively explored as promising noble-metal-free oxygen evolution reaction (OER) electrocatalysts. Herein, we report phase-selective syntheses of novel hierarchical CoTe2 and CoTe nanofleeces for efficient OER catalysts. The CoTe2 nanofleeces exhibited excellent electrocatalytic activity and stablity for OER in alkaline media. The CoTe2 catalyst exhibited superior OER activity compared to the CoTe catalyst, which is comparable to the state-of-the-art RuO2 catalyst. Density functional theory calculations showed that the binding strength and lateral interaction of the reaction intermediates on CoTe2 and CoTe are essential for determining the overpotential required under different conditions. This study provides valuable insights for the rational design of noble-metal-free OER catalysts with high performance and low cost by use of Co-based chalcogenides.

7.
Zhongguo Zhong Yao Za Zhi ; 41(11): 2070-2080, 2016 Jun.
Artículo en Zh | MEDLINE | ID: mdl-28901103

RESUMEN

To explore the processing mechanism of Aurantii Fructus decoction pieces used in Guangdong province and Hong Kong by analysing the chemical variation between raw and processed Aurantii Fructus with different methods based on UHPLC-Q-TOF-MS. The total ion chromatograms detected in positive and negative ion modes, and ion peak area ratio before and after processing were taken as variation indexes in the comparison. The results indicated that fermented Aurantii Fructus could produce three new ingredients, namely eriodictyol-7-glucoside, hesperetin-7-O-glucoside and 5-demethylnobiletin. At the same time, it could significantly increase the content of naringenin and hesperetin components, and could increase the content of such limonin derivatives as sudachinoid A, obacunoic acid and limoninand nomilinic acid. This suggests that the fermentation processing method of Aurantii Fructus decoction pieces used in Guangdong province and Hong Kong is of important significance for enhancing biological activity and bioavailability, and improving the clinical efficacy of Aurantii Fructus decoction pieces, and so is worth further protection and promotion.


Asunto(s)
Citrus/química , Medicamentos Herbarios Chinos/química , Flavonas/análisis , Glucósidos/análisis , Cromatografía Líquida de Alta Presión , Frutas/química , Espectrometría de Masas
8.
Tissue Eng Part A ; 30(9-10): 393-403, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38265006

RESUMEN

Millions of people suffer from tracheal defect worldwide each year, while autograft and allograft cannot meet existing treatment needs. Tissue-engineered trachea substitutes represent a promising treatment for tracheal defect, while lack of precisely personalized treatment abilities. Therefore, development of an artificial trachea that can be used for personalized transplantation is highly desired. In this study, we report the design and fabrication of an artificial trachea based on sericin microsphere (SM) by microtissue engineering technology and three-dimensional (3D) printing for personalized repair of tracheal defect. The SM possessed natural cell adhesion and promoting cell proliferation ability. Then, the microtissue was fabricated by coincubation of SM with chondrocytes and tracheal epithelial cells. This microtissue displayed good cytocompatibility and could support seed cell adhesion and proliferation. After that, this microtissue was individually assembled to form an artificial trachea by 3D printing. Notably, artificial trachea had an encouraging complete cartilaginous and epithelial structure after transplantation. Furthermore, the artificial trachea molecularly resembled native trachea as evidenced by similar expression of trachea-critical genes. Altogether, the work demonstrates the effectiveness of microtissue engineering and 3D printing for individual construction of artificial trachea, providing a promising approach for personalized treatment of tracheal defect.


Asunto(s)
Impresión Tridimensional , Ingeniería de Tejidos , Tráquea , Ingeniería de Tejidos/métodos , Animales , Andamios del Tejido/química , Medicina de Precisión , Humanos , Condrocitos/citología , Condrocitos/metabolismo , Células Epiteliales/citología , Células Epiteliales/metabolismo , Órganos Artificiales
9.
Front Pharmacol ; 15: 1272087, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38694923

RESUMEN

Chrysanthemi indic Flos (CIF) has been commonly consumed for the treatment of inflammation and related skin diseases. However, the potential bioactive components responsible for its anti-inflammatory and sensitive skin (SS) improvement activities, and the correlated mechanisms of action still remain unknown. In this work, it was firstly found that the CIF extract (CIFE) displayed arrestive free radical scavenging activity on DPPH and ABTS radicals, with no significant difference with positive control Trolox (p > 0.05). Then, compared to the negative group, CIFE markedly decreased the productions of the pro-inflammatory cytokines (IL-1ß, IL-6, PEG2, TNF-α, IFN-γ, NO) in LPS induced RAW264.7 cells in a dose-dependent manner (p < 0.01). Besides, CIFE strongly inhibited the COX-2 and hyaluronidase (HAase) with the IC50 values of 1.06 ± 0.01 µg/mL and 12.22 ± 0.39 µg/mL, indicating higher inhibitory effect than positive control of aspirin of 6.33 ± 0.05 µg/mL (p < 0.01), and comparable inhibitory effect with indometacin of 0.60 ± 0.03 µg/mL, and ascorbic acid of 11.03 ± 0.41 µg/mL (p > 0.05), respectively. Furthermore, kinetic assays with Lineweaver-Burk plot (Michaelis Menten equation) suggested that CIFE reversibly inhibited the COX-2 and HAase, with a mixed characteristics of competitive and non-competitive inhibition. Thereafter, multi-target affinity ultrafiltration liquid chromatography-mass spectrometry (UF-LC/MS) method was employed to fast fish out the potential COX-2 and HAase in CIFE. Herein, 13 components showed various affinity binding degrees to the COX-2 and HAase, while those components with relative binding affinity (RBA) value higher than 3.0, such as linarin and chlorogenic acid isomers, were deemed to be the most bioactive components for the anti-inflammatory and SS improvement activities of CIFE. Finally, the interaction mechanism, including binding energy, inhibition constant, docking sites, and the key amino acids involved in hydrogen bonds between the potential ligands and COX-2/HAase were simulated and confirmed with the molecule docking analysis. In summary, this study showcased the prominent anti-inflammatory and SS improvement activities of CIF, which would provide further insights on this functional medicinal plant to be a natural anti-SS remedy.

10.
Zhong Yao Cai ; 36(9): 1457-63, 2013 Sep.
Artículo en Zh | MEDLINE | ID: mdl-24620694

RESUMEN

OBJECTIVE: To analyze the volatile components of Platycladus orientalis extracted by headspace solid phase microextraction (HS-SPME) and steam distillation-extraction (DSE). METHODS: The volatile components which were extracted by DSE and analyzed by GC-MS; The HS-SPME conditions was optimized, and the volatile components were analyzed by GC-MS. RESULTS: Sixty-two kinds of volatile components extracted by DSE were isolated and 50 of them were identified; Sixty-eight kinds of volatile components extracted by HS-SPME were isolated and 67 of them were identified. CONCLUSION: Compared with DSE,HS-SPME has higher retrieval matching and sensitivity, which is more suitable for the analysis of the volatile components of P. orientalis.


Asunto(s)
Cupressaceae/química , Medicamentos Herbarios Chinos/química , Microextracción en Fase Sólida/métodos , Vapor , Compuestos Orgánicos Volátiles/análisis , Destilación , Medicamentos Herbarios Chinos/aislamiento & purificación , Cromatografía de Gases y Espectrometría de Masas , Hojas de la Planta/química , Tallos de la Planta/química , Reproducibilidad de los Resultados , Compuestos Orgánicos Volátiles/química , Compuestos Orgánicos Volátiles/aislamiento & purificación , Volatilización
11.
J Phys Chem Lett ; 14(42): 9385-9391, 2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37823819

RESUMEN

The poisoning of catalysts has always been a vital issue in catalytic reactions. In this study, direct observation of the interaction of CO and oxygen-poisoned Co(0001) has been achieved with scanning tunneling microscopy (STM), temperature-programmed desorption (TPD), and density functional theory calculation. A two-stage adsorption process of CO on a well-prepared p(2×2)-O layer covered Co(0001) was directly visualized. With increasing annealing time at a certain temperature after the CO dosage, the ordered (2 × 2) pattern formed in the first stage can be recovered, suggesting the weak interaction of CO with the O-covered Co(0001) surface in the latter stage. Compared to the clean Co(0001) surface, on an oxygen-poisoned surface, no further reaction was observed, illustrating the poisoning of the catalyst. Moreover, TPD results are in good agreement with the STM observation; a desorption energy of 0.35 eV is evaluated with a simple but accurate scheme.

12.
Front Pharmacol ; 13: 1018438, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36304158

RESUMEN

Baiying Qingmai Formulation (BF) is a classical clinical prescription used for decades to treat thromboangiitis obliterans (TAO). Although it effectively relieves pain and ischemic ulcers in patients with TAO, its anti-TAO mechanisms remain unclear. The chemical components of BF were analyzed using high-performance liquid chromatography and the potential targets of the compounds identified in BF were analyzed using molecular docking. Further, the signaling pathways and molecular mechanism of BF in treating TAO were studied using a rat model of TAO. Seven compounds (gallic acid, catechin, chlorogenic acid, caffeic acid, paeoniflorin, quercetin, and paeonol) were identified in BF, and molecular docking predicted their high affinities with HMGB1/RAGE/NF-κB proteins. In in vivo studies, BF not only inhibited the protein expression of HMGB1, RAGE, ICAM-1, and VCAM-1; mRNA levels of HMGB1 and RAGE; and the phosphorylation of NF-κB, ERK, Janus kinase (JNK) and p38 MAPK in the femoral artery, but also reduced the levels of inflammatory cytokines (IL-6, TNF-α, IL-1ß, HMGB1) and stable metabolite (TXB2) of cytokine promoting thrombosis (TXA2) in the plasma. Moreover, BF stimulated the secretion of stable metabolite (6-keto-PGF1α) of cytokine inhibiting thrombosis (PGI2) in the plasma. BF inhibited the inflammatory response and thrombosis in the femoral artery, thus reducing the degree of vascular occlusion, which alleviated the symptoms in rats with TAO. Our findings suggest that BF ameliorates TAO by inhibiting the activation of the ERK, JNK, p38 MAPK and HMGB1/RAGE/NF-κB signaling pathways, thereby providing novel ideas for the treatment of TAO and essential information for the further development and utilization of BF as a promising drug to treat TAO.

13.
J Mater Chem B ; 10(42): 8750-8759, 2022 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-36254821

RESUMEN

Drug delivery systems (DDS) play a vital role in the construction of tumor vaccines and can promote their therapeutic effect. Taking advantage of the versatile binding sites and bioreduction ability of human serum albumin (HSA), Au ions could be absorbed, reduced and nucleated to generate gold nanoparticles (AuNPs) on HSA without complicated intermediates, forming a DDS that can transform light to heat. Here, we designed self-generated AuNPs templated by HSA (HSA@AuNP). The HSA@AuNPs can deliver peptides, amplify the immune response and achieve combined photothermal therapy and immunotherapy. Human melanoma antigen gp10025-33 (hgp100) peptide, a common hydrophilic tumor vaccine peptide that can be easily encapsulated in HSA, was chosen to be incorporated into the HSA@AuNPs. The in vitro and in vivo studies demonstrated that the nanoparticles can mediate light-to-heat transduction under near-infrared irradiation (NIR), achieving tumor ablation and enhancing antitumor immunity. Our design can insulate toxic agents, streamline flux, increase the transition efficiency of interactants and improve the product yield, contributing a novel modality for facile and green synthesis of nanovaccines.


Asunto(s)
Vacunas contra el Cáncer , Nanopartículas del Metal , Neoplasias , Humanos , Oro/química , Albúmina Sérica Humana/química , Nanopartículas del Metal/química , Sistemas de Liberación de Medicamentos , Neoplasias/tratamiento farmacológico
14.
J Phys Chem Lett ; : 5131-5136, 2022 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-35657666

RESUMEN

Oxygen dissociation and activation on surfaces play a crucial role in heterogeneous catalysis and oxidation processes. In this study, we have conducted a series of scanning tunneling microscopy (STM) experiments combined with density functional theory calculation to investigate the oxidation process in a single crystal Co(0001) surface. For the first time, we show a comprehensive in situ STM study of the oxidation process of Co(0001) from an atomic point of view. With low O2 exposure at 90 K, chemisorbed oxygen pairs are observed showing a dumbbell-like STM feature. At a relatively higher temperature range of 160-250 K, a large-scale p(2 × 2)-O adlayer forms and the O adatoms show surprisingly high mobility. With the temperature of Co(0001) kept at ≥300 K, adsorption of oxygen leads to fast oxidation of the surface to amorphous cotton-like protrusions, which occur initially at the step/edge sites and interstitial defect sites.

15.
Artículo en Inglés | MEDLINE | ID: mdl-35685720

RESUMEN

Fuzi (Aconitum carmichaelii Debx) has been traditionally used for the treatment of ulcerative colitis (UC) in China for thousands of years. The total alkaloids of A. carmichaelii (AAC) have been considered as the main medicinal components of fuzi, whereas its underlying anti-UC mechanisms remain elusive. In the present study, the dextran sulfate sodium (DSS)-induced UC mice model, which was consistent with the symptoms and pathological features of human UC, was established to comprehensively evaluate the anti-UC effects of AAC. The results indicated that AAC effectively improved the weight loss, disease activity index (DAI), spleen hyperplasia, and colon shortening, and thus alleviated the symptoms of UC mice. Meanwhile, AAC not only inhibited the MPO enzyme and the abnormal secretion of inflammatory cytokines (TNF-α, IL-1ß, IL-6, IFN-γ, and IL-17A) and suppressed the overexpression of inflammatory mediators (TNF-α, IL-1ß, and IL-6) of mRNA but also reduced the phosphorylation of p38 MAPK, ERK, and JNK, and the protein expressions of NF-κB, IκB-α, STAT3, and JAK2 in the colon tissue. Furthermore, the LC-MS/MS quantitative determination suggested that the three low toxic monoester alkaloids were higher in both contents and proportion than that of the three high toxic diester alkaloids. Additionally, molecular docking was hired to investigate the interactions between alkaloid-receptor complexes, and it suggested the three monoester alkaloids exhibited higher binding affinities with the key target proteins of MAPK, NF-κB, and STAT3. Our finding showcased the noteworthy anti-UC effects of AAC based on the MAPK/NF-κB/STAT3 signaling pathway, which would provide practical and edge-cutting background information for the development and utilization of A. carmichaelii as a potential natural anti-UC remedy.

16.
NPJ Vaccines ; 7(1): 144, 2022 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-36371432

RESUMEN

Since the first outbreak in December 2019, SARS-CoV-2 has been constantly evolving and five variants have been classified as Variant of Concern (VOC) by the World Health Organization (WHO). These VOCs were found to enhance transmission and/or decrease neutralization capabilities of monoclonal antibodies and vaccine-induced antibodies. Here, we successfully designed and produced a recombinant COVID-19 vaccine in CHO cells at a high yield. The vaccine antigen contains four hot spot substitutions, K417N, E484K, N501Y and D614G, based on a prefusion-stabilized spike trimer of SARS-CoV-2 (S-6P) and formulated with an Alum/CpG 7909 dual adjuvant system. Results of immunogenicity studies showed that the variant vaccine elicited robust cross-neutralizing antibody responses against SARS-CoV-2 prototype (Wuhan) strain and all 5 VOCs. It further, stimulated a TH1 (T Helper type 1) cytokine profile and substantial CD4+ T cell responses in BALB/c mice and rhesus macaques were recorded. Protective efficacy of the vaccine candidate was evaluated in hamster and rhesus macaque models of SARS-CoV-2. In Golden Syrian hamsters challenged with Beta or Delta strains, the vaccine candidate reduced the viral loads in nasal turbinates and lung tissues, accompanied by significant weight gain and relieved inflammation in the lungs. In rhesus macaque challenged with prototype SARS-CoV-2, the vaccine candidate decreased viral shedding in throat, anal, blood swabs over time, reduced viral loads of bronchus and lung tissue, and effectively relieved the lung pathological inflammatory response. Together, our data demonstrated the broadly neutralizing activity and efficacy of the variant vaccine against both prototype and current VOCs of SARS-CoV-2, justifying further clinical development.

17.
J Ethnopharmacol ; 270: 113773, 2021 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-33388430

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Qingxue jiedu Formulation (QF) is composed of two classic prescriptions which have been clinically used for more than 5 centuries and appropriately modified through basic theory of traditional Chinese medicine for treating various skin inflammation such as atopic dermatitis (AD), acute dermatitis and rash. Although QF possesses a prominent clinical therapeutic effect, seldom pharmacological studies on its anti-AD activity are conducted. AIM OF THE STUDY: We used AD mice model to investigate the anti-AD activities of QF, as well as its underlying molecular mechanisms which involved signal transducer and activator of transcription 3 (STAT3), nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. MATERIALS AND METHODS: 2,4-dinitrofluorobenzene (DNFB)-induced AD mice were used to collect serum and skin tissues for consequential determination. The levels of various inflammatory factors [interleukin (IL)-12, Interferon (IFN)-γ, tumor necrosis factor (TNF)-α, IL-4, IL-6 and immunoglobulin E (IgE)] were determined by enzyme-linked immunosorbent assay (ELISA). Real-time polymerase chain reaction (RT-PCR) was contributed to detect the effects of relevant inflammatory factors on mRNA. The roles of STAT3, NF-κB and MAPK signaling pathways in AD response were analyzed by Western blotting (WB), and the thickening of mice dorsal skin and inflammatory cell infiltration were observed by hematoxylin and eosin (H&E) staining. RESULTS: QF significantly reduced the skin thickening, inflammatory cell infiltration and other symptoms in AD mice. The levels of IL-12, TNF-α, IL-4, IL-6 and IgE were decreased, while IFN-γ was increased by QF in the ELISA analysis. QF lessened the levels of lL-6 and elevated IFN-γ on the mRNA level. In addition, WB analysis showed QF thoroughly inhibited the activation of NF-κB, STAT3 and phosphorylation of JAK1, JAK2, JAK3, while partially suppressed MAPK signaling pathways. CONCLUSIONS: QF inhibited the activations of STAT3, MAPK and NF-κB signaling pathways and possessed a significant therapeutic effect on AD. Therefore, QF deserves our continuous attention and research as a prominent medicine for AD.


Asunto(s)
Dermatitis Atópica/tratamiento farmacológico , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Proteínas Quinasas Activadas por Mitógenos/antagonistas & inhibidores , FN-kappa B/antagonistas & inhibidores , Factor de Transcripción STAT3/antagonistas & inhibidores , Animales , Citocinas/sangre , Citocinas/genética , Dermatitis Atópica/sangre , Dermatitis Atópica/inducido químicamente , Dermatitis Atópica/patología , Dinitrofluorobenceno/toxicidad , Modelos Animales de Enfermedad , Medicamentos Herbarios Chinos/química , Inmunoglobulina E/sangre , Masculino , Ratones Endogámicos C57BL , Proteínas Quinasas Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , Factor de Transcripción STAT3/metabolismo
18.
J Colloid Interface Sci ; 590: 226-237, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33548606

RESUMEN

Dopant engineering in nanostructured materials is an effective strategy to enhance electrochemical performances via regulating the electronic structures and achieving more active sites. In this work, a robust electrode based on Fe and Mn co-doped Co3S4 (FM-Co3S4) ultrathin nanosheet arrays (NSAs) on the Ni foam substrate is prepared through a facile hydrothermal method followed by a subsequent sulfurization reaction. It has been found that the incorporation of Fe ions is beneficial to higher specific capacity of the final electrode and Mn ions contribute to the excellent rate capability in the reversible redox processes. Density functional theory (DFT) calculations further verify that the Mn doping in the Co3S4 obviously shorten the energy gap of Co3S4, which favors the electrochemical performances. Due to the synergetic effects of different transition metal ions, the as-prepared FM-Co3S4 ultrathin NSAs exhibit a high specific capacity of 390 mAh g-1 at 5 A g-1, as well as superior rate capability and excellent cycling stability. Moreover, the corresponding quasi-solid-state hybrid supercapacitors constructed with the FM-Co3S4 ultrathin NSAs and active carbon exhibit a high energy density of 55 Wh kg-1 at the power density of 752 W kg-1. These findings demonstrate a new platform for developing high-performance electrodes for energy storage applications.

19.
Front Pharmacol ; 12: 749626, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34925011

RESUMEN

Background: Danshen Baibixiao (DB) is a traditional Chinese medicine formula, which has been used to treat psoriasis for decades. Although DB shows good efficacy in clinical practice, the pharmacological effects and underlying mechanisms of DB remain elusive. This study aimed to evaluate the anti-psoriatic effects of DB and explore its underlying mechanisms in an imiquimod (IMQ)-induced psoriasis-like mouse model. Materials and methods: DB was orally administered on IMQ-induced psoriatic mice. Psoriasis area severity index (PASI) was used to evaluate the severity of the inflammation in skin, and histological changes were evaluated by hematoxylin and eosin (H and E) staining. Levels of inflammatory cytokines, such as tumor necrosis factor α (TNF-α), interleukin (IL)-17A, IL-23, IL-6, IL-1ß and IL-22 in serum were assessed by enzyme-linked immunosorbent assay (ELISA). mRNA expressions of IL-17A, IL-23, IL-6 and IL-22 were determined by real-time polymerase chain reaction (PCR). Expression levels of proteins related to NF-κB, STAT3 and MAPKs signaling pathways were measured by western blotting (WB). Results: DB significantly ameliorated the psoriatic symptoms in IMQ-induced mice. The serum levels of inflammatory cytokines (TNF-α, IL-17A, IL-23, IL-6, IL-1ß and IL-22) were decreased, and mRNA expressions of IL-17A, IL-23, IL-6 and IL-22 in skin tissues were down-regulated. Moreover, WB analysis indicated that DB inhibited the activation of NF-κB, STAT3 and MAPKs signaling pathways. Conclusion: This study confirms the anti-psoriatic activity of DB in IMQ-induced psoriasis-like mice. The possible mechanism may relate to the activities of regulating the IL-23/TH-17 axis and suppressing the activation of NF-κB, STAT3 and MAPKs signaling pathways.

20.
Cell Signal ; 77: 109812, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33164880

RESUMEN

It has been widely reported that exosomes derived from mesenchymal stem cells (MSCs) have a protective effect on myocardial infarction (MI). However, the specific molecules which play a damaging role in MSCs shuttled miRNAs are much less explored. MiRNA-153-3p (miR-153-3p) is a vital miRNA which has been proved to modulate cell proliferation, apoptosis, angiogenesis, peritoneal fibrosis and aortic calcification. Here, we aim to study the effect and mechanism of miR-153-3p in MSC-derived exosomes on hypoxia-induced myocardial and microvascular damage. The exosomes of MSCs were isolated and identified, and the MSCs-exosomes with low expression of miR-153-3p (exo-miR-153-3p-) were constructed to interfere with the endothelial cells and cardiomyocytes in the oxygen-glucose deprivation (OGD) model. The viability, apoptosis, angiogenesis of endothelial cells and cardiomyocytes were determined. Additionally, ANGPT1/VEGF/VEGFR2/PI3K/Akt/eNOS pathway was detected by ELISA and/or western blot. The results illustrated that exo-miR-153-3p- significantly reduced the apoptosis of endothelial cells and cardiomyocytes and promoted their viability. Meanwhile, exo-miR-153-3p- can promote the angiogenesis of endothelial cells. Mechanistically, miR-153-3p regulates the VEGF/VEGFR2/PI3K/Akt/eNOS pathways by targeting ANGPT1. Intervention with VEGFR2 inhibitor (SU1498, 1 µM) remarkably reversed the protective effect of exo-miR-153-3p- in vascular endothelial cells and cardiomyocytes treated by OGD. Collectively, MSCs-derived exosomes with low-expressed miR-153-3p notably promotes the activation of ANGPT1 and the VEGF/VEGFR2 /PI3K/Akt/eNOS pathways, thereby preventing the damages endothelial cells and cardiomyocytes against hypoxia.


Asunto(s)
Angiopoyetina 1/metabolismo , Exosomas/metabolismo , MicroARNs/metabolismo , Transducción de Señal , Angiopoyetina 1/química , Angiopoyetina 1/genética , Animales , Antagomirs/metabolismo , Apoptosis , Hipoxia de la Célula , Células Endoteliales/citología , Células Endoteliales/metabolismo , Masculino , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Ratones , Ratones Endogámicos C57BL , MicroARNs/antagonistas & inhibidores , MicroARNs/genética , Miocitos Cardíacos/citología , Miocitos Cardíacos/metabolismo , Neovascularización Fisiológica , Óxido Nítrico Sintasa de Tipo III/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Factor A de Crecimiento Endotelial Vascular/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA