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1.
Acta Biochim Biophys Sin (Shanghai) ; 56(5): 789-804, 2024 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-38686458

RESUMEN

Acute lung injury (ALI) is a serious condition characterized by damage to the lungs. Recent research has revealed that activation of the NLRP3 inflammasome in alveolar macrophages, a type of immune cell in the lungs, plays a key role in the development of ALI. This process, known as pyroptosis, contributes significantly to ALI pathogenesis. Researchers have conducted comprehensive bioinformatics analyses and identified 15 key genes associated with alveolar macrophage pyroptosis in ALI. Among these, NLRP3 has emerged as a crucial regulator. This study further reveal that the ULK1 protein diminishes the expression of NLRP3, thereby reducing the immune response of alveolar macrophages and mitigating ALI. Conversely, TRAF3, another protein, is found to inhibit ULK1 through a process called ubiquitination, leading to increased activation of the NLRP3 inflammasome and exacerbation of ALI. This TRAF3-mediated suppression of ULK1 and subsequent activation of NLRP3 are confirmed through various in vitro and in vivo experiments. The presence of abundant M0 and M1 alveolar macrophages in the ALI tissue samples further support these findings. This research highlights the TRAF3-ULK1-NLRP3 regulatory axis as a pivotal pathway in ALI development and suggests that targeting this axis could be an effective therapeutic strategy for ALI treatment.


Asunto(s)
Lesión Pulmonar Aguda , Homólogo de la Proteína 1 Relacionada con la Autofagia , Macrófagos Alveolares , Ratones Endogámicos C57BL , Proteína con Dominio Pirina 3 de la Familia NLR , Piroptosis , Factor 3 Asociado a Receptor de TNF , Lesión Pulmonar Aguda/metabolismo , Lesión Pulmonar Aguda/patología , Lesión Pulmonar Aguda/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/patología , Animales , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Homólogo de la Proteína 1 Relacionada con la Autofagia/genética , Ratones , Factor 3 Asociado a Receptor de TNF/metabolismo , Factor 3 Asociado a Receptor de TNF/genética , Humanos , Masculino , Inflamasomas/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Transducción de Señal , Ubiquitinación
2.
Waste Manag ; 178: 76-84, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38382349

RESUMEN

The efficient and sustainable recovery of rare earth resources from spent NdFeB magnets has received considerable and increasing attention. However, the currently prevalent NdFeB magnets recovery techniques focus only on the recovery for rare earth elements (REEs), some of which also recover cobalt (Co) or boron (B). Herein, a simple mechanochemical strategy was proposed to recover REE, Co, and B from spent NdFeB magnets by mixing the NdFeB magnets powder and FeCl3 6H2O through the grinding-roasting-water leaching technological route. The results indicated high leaching efficiencies of 98.94 % for REEs, 99.99 % for Co, and 93.36 % for B from the NdFeB magnets. Additionally, iron remains in the leaching residue as iron oxide (96.73 wt %), achieving the complete separation of REEs, Co, B, and Fe. This mechanochemical based technology offers a green and efficient recovery process, facilitating more effective synergistic recovery of valuable elements from spent NdFeB magnets.

3.
BMC Surg ; 23(1): 341, 2023 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-37950218

RESUMEN

BACKGROUND: Video-assisted laparoscopic Heller myotomy (LHM) has become the standard treatment option for achalasia. While robotic surgery offering some specific advantages such as better three-dimensional (3D) stereoscopic vision, hand-eye consistency, and flexibility and stability with the endowrist is expected to be shorter in learning curve than that of LHM for surgeons who are proficient in LHM. The aim of this study was to describe a single surgeon's experience related to the transition from video-assisted laparoscopic to robotic Heller myotomy with Dor fundoplication. METHODS: We conducted a retrospective observational study based on the recorded data of the first 66 Heller myotomy performed with laparoscopic Heller myotomy with Dor fundoplication (LHMD, 26 cases) and with the robotic Heller myotomy with Dor fundoplication (RHMD, 40 cases) by the same surgeon in Department of Thoracic Surgery of The First Affiliated Hospital of Nanchang University in China. The operation time and intraoperative blood loss were analyzed using the cumulative sum (CUSUM) method. Corresponding statistical tests were used to compare outcomes of both serials of cases. RESULTS: The median operation time was shorter in the RHMD group compared to the LHMD group (130 [IQR 123-141] minutes vs. 163 [IQR 153-169]) minutes, p < 0.001). In the RHMD group, one patient (2.5%) experienced mucosal perforation, whereas, in the LHMD group, the incidence of this complication was significantly higher at 19.2% (5 patients) (p = 0.031). Based on cumulative sum analyses, operation time decreased starting with case 20 in the LHMD group and with case 18 in the RHMD group. Intraoperative blood loss tended to decline starting with case 19 in the LHMD group and with case 16 in the RHMD group. CONCLUSIONS: Both RHMD and LHMD are effective surgical procedures for symptom relief of achalasia patients. RHMD demonstrates superior outcomes in terms of operation time and mucosal perforation during surgery compared to LHMD. Proficiency with RHMD can be achieved after approximately 16-18 cases, while that of LHMD can be obtained after around 19-20 cases.


Asunto(s)
Acalasia del Esófago , Miotomía de Heller , Laparoscopía , Procedimientos Quirúrgicos Robotizados , Humanos , Fundoplicación , Miotomía de Heller/métodos , Acalasia del Esófago/cirugía , Pérdida de Sangre Quirúrgica , Resultado del Tratamiento , Laparoscopía/métodos
4.
Carbohydr Polym ; 280: 119009, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35027122

RESUMEN

In this study, a kind of polymeric ionic liquid (PIL) called PIL-Cl was synthesized and modified to obtain conductive graphene coated carboxymethyl cellulose hybrid fibers. Carboxymethyl cellulose (CMC) was formed into fibers by wet spinning assisted with PILCl. Co-precipitation test of CMC and PIL-Cl demonstrated that PIL-Cl could precipitate with CMC through strong electrostatic interaction and molar ratio of CMC and PIL-Cl (calculated in repeating units) would affect the formation of precipitation. Secondly, modified PIL-Cl named PIL-Ac was used as an intermediate connecting CMC fiber and graphene to fabricate conductive CMC/PIL/graphene fibers. A series of tests were performed on CMC/PIL/graphene fibers, including Raman spectroscopy, scanning electron microscopy and conductivity test. The results showed that PIL-Cl could help form CMC fiber, and PIL-Ac could functionalize it and make it conductive.


Asunto(s)
Carboximetilcelulosa de Sodio/química , Grafito/química , Líquidos Iónicos/química , Polímeros/química , Conductividad Eléctrica , Enlace de Hidrógeno , Polímeros/síntesis química , Electricidad Estática
5.
Eur J Histochem ; 65(4)2021 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-34852453

RESUMEN

Acute lung injury/acute respiratory distress syndrome (ALI/ARDS) is a kind of diffuse inflammatory injury caused by various factors, characterized by respiratory distress and progressive hypoxemia. It is a common clinical critical illness. The aim of this study was to investigate the effect and mechanism of the Mucin1 (MUC1) gene and its recombinant protein on lipopolysaccharide (LPS)-induced ALI/ARDS. We cultured human alveolar epithelial cell line (BEAS-2B) and used MUC1 overexpression lentivirus to detect the effect of MUC1 gene on BEAS-2B cells. In addition, we used LPS to induce ALI/ARDS in C57/BL6 mice and use hematoxylin and eosin (H&E) staining to verify the effect of their modeling. Recombinant MUC1 protein was injected subcutaneously into mice. We examined the effect of MUC1 on ALI/ARDS in mice by detecting the expression of inflammatory factors and oxidative stress molecules in mouse lung tissue, bronchoalveolar lavage fluid (BALF) and serum. Overexpression of MUC1 effectively ameliorated LPS-induced damage to BEAS-2B cells. Results of H&E staining indicate that LPS successfully induced ALI/ARDS in mice and MUC1 attenuated lung injury. MUC1 also reduced the expression of inflammatory factors (IL-1ß, TNF-α, IL-6 and IL-8) and oxidative stress levels in mice. In addition, LPS results in an increase in the activity of the TLR4/NF-κB signaling pathway in mice, whereas MUC1 decreased the expression of the TLR4/NF-κB signaling pathway. MUC1 inhibited the activity of TLR4/NF-κB signaling pathway and reduced the level of inflammation and oxidative stress in lung tissue of ALI mice.


Asunto(s)
Lesión Pulmonar Aguda , Mucina-1/farmacología , Estrés Oxidativo/efectos de los fármacos , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/tratamiento farmacológico , Lesión Pulmonar Aguda/metabolismo , Lesión Pulmonar Aguda/patología , Animales , Línea Celular , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Inflamación/patología , Lipopolisacáridos/toxicidad , Masculino , Ratones , Proteínas Recombinantes/farmacología
6.
Front Oncol ; 11: 669518, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34178653

RESUMEN

In non-small-cell lung carcinoma (NSCLC), aberrant activation of mammalian target of rapamycin (mTOR) contributes to tumorigenesis and cancer progression. PQR620 is a novel and highly-potent mTOR kinase inhibitor. We here tested its potential activity in NSCLC cells. In primary human NSCLC cells and established cell lines (A549 and NCI-H1944), PQR620 inhibited cell growth, proliferation, and cell cycle progression, as well as cell migration and invasion, while inducing significant apoptosis activation. PQR620 disrupted assembles of mTOR complex 1 (mTOR-Raptor) and mTOR complex 2 (mTOR-Rictor-Sin1), and blocked Akt, S6K1, and S6 phosphorylations in NSCLC cells. Restoring Akt-mTOR activation by a constitutively-active Akt1 (S473D) only partially inhibited PQR620-induced cytotoxicity in NSCLC cells. PQR620 was yet cytotoxic in Akt1/2-silenced NSCLC cells, supporting the existence of Akt-mTOR-independent mechanisms. Indeed, PQR620 induced sphingosine kinase 1 (SphK1) inhibition, ceramide production and oxidative stress in primary NSCLC cells. In vivo studies demonstrated that daily oral administration of a single dose of PQR620 potently inhibited primary NSCLC xenograft growth in severe combined immune deficient mice. In PQR620-treated xenograft tissues, Akt-mTOR inactivation, apoptosis induction, SphK1 inhibition and oxidative stress were detected. In conclusion, PQR620 exerted potent anti-NSCLC cell activity via mTOR-dependent and -independent mechanisms.

7.
ACS Appl Mater Interfaces ; 13(13): 15168-15177, 2021 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-33760597

RESUMEN

Single-atom catalysts effectively integrate the respective advantages of homogeneous and heterogeneous catalysts and are a pioneering research frontier in catalysis by virtue of their maximized utility of metal atoms and distinct atomic configuration. However, development of such catalysts is still in the early stages. Herein, atomically dispersed vanadium (V) sites that are coordinated by N atoms and inlaid within N-incorporated porous carbon networks were prepared through a top-down strategy by annealing a V-containing metal-organic framework, NH2-MIL-101(V), followed by acid etching. The resulting V-N-C-600 catalyst exhibits unexpected catalytic reactivity, selectivity, and robust stability for the direct aerobic oxidation of benzylamine to generate N-benzylidene benzylamine with molecular oxygen under mild conditions. The turnover frequency reaches 53.9 h-1, which is much superior to those achieved over the commercial V2O5 and state-of-the-art non-noble metal heterogeneous catalysts reported in the literature. Kinetic analysis reveals a low activation energy barrier (37 kJ mol-1) for the benzylamine oxidation and indicates that a carbocationic intermediate is involved in the reaction mechanism. The synergistic effect between the isolated V single-atomic sites and N-doped hierarchically porous carbon network boosts the performance of V-N-C-600. Moreover, V-N-C-600 exhibits a wide generality for the efficient synthesis of a set of symmetrical imines, unsymmetrical imines, and imine derivatives.

8.
BMC Chem ; 15(1): 9, 2021 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-33546740

RESUMEN

This work presents an investigation on the composition and structure of polysaccharides from the roots of Tetrastigma hemsleyanum (THP) and its associated antioxidant activity. It further explores the protective effect of THP on RAW264.7 cells against cytotoxicity induced by H2O2. Ion chromatography (IC) revealed that THP contained glucose, arabinose, mannose, glucuronic acid, galactose and galacturonic acid, in different molar ratios. Furthermore, gel permeation chromatography-refractive index-multiangle laser light scattering (GPC-RI-MALS) was employed to deduce the relative molecular mass (Mw) of the polysaccharide, which was 177.1 ± 1.8 kDa. Fourier transform infrared spectroscopy (FT-IR) and Congo red binding assay highlighted that the THP had a steady α-triple helix conformation. Similarly, assays of antioxidant activity disclosed that THP had reasonable concentration-dependent hydroxyl radical and superoxide radical scavenging activities, peroxidation inhibition ability and ferrous ion chelating potency, in addition to a significant 1,1-diphenyl-2-picrylhydrazyl radical scavenging capacity. Moreover, THP could protect RAW264.7 cells against H2O2-induced cytotoxicity by decreasing intracellular ROS levels, reducing catalase (CAT) and superoxide dismutase (SOD) activities, increasing lactate dehydrogenase (LDH) activity and increment in malondialdehyde (MDA) level. Data retrieved from the in vitro models explicitly established the antioxidant capability of polysaccharides from T. hemsleyanum root extracts.

9.
Transplantation ; 105(3): 529-539, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-32852406

RESUMEN

BACKGROUND: MicroRNA-145 (miR-145) has been shown to play a critical role in ischemia/reperfusion (I/R) injury; however, the expression and function of miR-145 in lung I/R injury have not been reported yet. This study aimed to elucidate the potential effects of miR-145 in lung I/R injury. METHODS: Lung I/R mice models and hypoxia/reoxygenation (H/R) pulmonary microvascular endothelial cell models were established. The expression of miR-145 and sirtuin 1 (SIRT1) was measured with reverse transcription-quantitative polymerase chain reaction and Western blot analysis in mouse lung tissue and cells. Artificial modulation of miR-145 and SIRT1 (downregulation) was done in I/R mice and H/R cells. Additionally, Pao2/FiO2 ratio, wet weight-to-dry weight ratio, and cell apoptosis in mouse lung tissues were determined by blood gas analyzer, electronic balance, and deoxyuridine triphosphate-biotin nick end-labeling assay, respectively. Autophagy marker Beclin 1 and LC3 expression, NF-κB acetylation levels, and autophagy bodies were detected in cell H/R and mouse I/R models by Western blot analysis. pulmonary microvascular endothelial cell apoptosis was detected with flow cytometry. RESULTS: miR-145 was abundantly expressed in the lung tissue of mice and PMVECs following I/R injury. In addition, miR-145 directly targeted SIRT1, which led to significantly decreased Pao2/FiO2 ratio and increased wet weight-to-dry weight ratio, elevated acetylation levels and transcriptional activity of NF-κB, upregulated expressions of tumor necrosis factor-α, interleukins-6, and Beclin 1, autophagy bodies, cell apoptosis, as well as LC3-II/LC3I ratio. CONCLUSIONS: In summary, miR-145 enhances autophagy and aggravates lung I/R injury by promoting NF-κB transcriptional activity via SIRT1 expression.


Asunto(s)
Beclina-1/metabolismo , Regulación de la Expresión Génica , MicroARNs/genética , FN-kappa B/metabolismo , Daño por Reperfusión/genética , Sirtuina 1/genética , Regulación hacia Arriba , Animales , Apoptosis , Autofagia , Modelos Animales de Enfermedad , Pulmón/irrigación sanguínea , Masculino , Ratones , MicroARNs/antagonistas & inhibidores , MicroARNs/biosíntesis , Daño por Reperfusión/metabolismo , Daño por Reperfusión/patología , Transducción de Señal , Sirtuina 1/biosíntesis
10.
Am J Physiol Lung Cell Mol Physiol ; 319(1): L1-L10, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32267722

RESUMEN

Lung ischemia-reperfusion (I/R) injury severely endangers human health, and recent studies have suggested that certain microRNAs (miRNAs) play important roles in this pathological phenomenon. The current study aimed to ascertain the ability of miR-223 to influence lung I/R injury by targeting hypoxia-inducible factor-2α (HIF2α). First, mouse models of lung I/R injury were established: during surgical procedures, pulmonary arteries and veins and unilateral pulmonary portal vessels were blocked and resuming bilateral pulmonary ventilation, followed by restoration of bipulmonary ventilation. In addition, a lung I/R injury cell model was constructed by exposure to hypoxic reoxygenation (H/R) in mouse pulmonary microvascular endothelial cells (PMVECs). Expression of miR-223, HIF2α, and ß-catenin in tissues or cells was determined by RT-qPCR and Western blot analysis. Correlation between miR-223 and HIF2α was analyzed by dual luciferase reporter gene assay. Furthermore, lung tissue injury and mouse PMVEC apoptosis was evaluated by hematoxylin and eosin (H&E), TUNEL staining, and flow cytometry. Autophagosomes in cells were detected by light chain 3 immunofluorescence assay. miR-223 was expressed at a high level while HIF2α/ß-catenin was downregulated in tissues and cells with lung I/R injury. Furthermore, miR-223 targeted and repressed HIF2α expression to downregulate ß-catenin expression. The miR-223/HIF2α/ß-catenin axis aggravated H/R injury in mouse PMVECs and lung I/R injury in mice by enhancing autophagy. Taken together, miR-223 inhibits HIF2α to repress ß-catenin, thus contributing to autophagy to complicate lung I/R injury. These findings provide a promising therapeutic target for treating lung I/R injury.

11.
Bioorg Chem ; 88: 102958, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31054434

RESUMEN

A series of novel 1,4-benzodioxane thiazolidinedione piperazine derivatives targeting FabH were designed and synthesized. The compounds exhibited better inhibitory activity against Gram-negative bacteria by computer-assisted screening, antibacterial activity test and E. coli FabH inhibitory activity test, wherein compound 6j exhibited the most significant inhibitory activity (MIC = 1.80 µΜ for P. aeruginosa, MIC = 1.56 µΜ for E. coli). Besides, compound 6j still showed the best E. coli FabH inhibitory activity (IC50 = 0.06 µΜ). Moreover, the antibacterial activities of all compounds were strongly correlated with the inhibitory ability of FabH, with a correlation coefficient of 0.954. Computational docking studies also showed that compound 6j has interacting with FabH key residues in the active site.


Asunto(s)
Acetiltransferasas/antagonistas & inhibidores , Dioxinas/farmacología , Inhibidores Enzimáticos/farmacología , Proteínas de Escherichia coli/antagonistas & inhibidores , Simulación del Acoplamiento Molecular , Piperazina/farmacología , Tiazolidinedionas/farmacología , 3-Oxoacil-(Proteína Transportadora de Acil) Sintasa , Acetiltransferasas/metabolismo , Dioxinas/síntesis química , Dioxinas/química , Relación Dosis-Respuesta a Droga , Diseño de Fármacos , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Escherichia coli/enzimología , Proteínas de Escherichia coli/metabolismo , Acido Graso Sintasa Tipo II/antagonistas & inhibidores , Acido Graso Sintasa Tipo II/metabolismo , Estructura Molecular , Piperazina/síntesis química , Piperazina/química , Relación Estructura-Actividad , Tiazolidinedionas/síntesis química , Tiazolidinedionas/química
12.
ACS Nano ; 10(4): 4209-18, 2016 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-26967254

RESUMEN

The blood-brain barrier (BBB) is partially disrupted in brain tumors. Despite the gaps in the BBB, there is an inadequate amount of pharmacological agents delivered into the brain. Thus, the low delivery efficiency renders many of these agents ineffective in treating brain cancer. In this report, we proposed an "autocatalytic" approach for increasing the transport of nanoparticles into the brain. In this strategy, a small number of nanoparticles enter into the brain via transcytosis or through the BBB gaps. After penetrating the BBB, the nanoparticles release BBB modulators, which enables more nanoparticles to be transported, creating a positive feedback loop for increased delivery. Specifically, we demonstrated that these autocatalytic brain tumor-targeting poly(amine-co-ester) terpolymer nanoparticles (ABTT NPs) can readily cross the BBB and preferentially accumulate in brain tumors at a concentration of 4.3- and 94.0-fold greater than that in the liver and in brain regions without tumors, respectively. We further demonstrated that ABTT NPs were capable of mediating brain cancer gene therapy and chemotherapy. Our results suggest ABTT NPs can prime the brain to increase the systemic delivery of therapeutics for treating brain malignancies.


Asunto(s)
Barrera Hematoencefálica/metabolismo , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/terapia , Nanopartículas/química , Animales , Antineoplásicos/administración & dosificación , Transporte Biológico , Línea Celular Tumoral , Ácidos Decanoicos/química , Sistemas de Liberación de Medicamentos , Etanolaminas/química , Femenino , Terapia Genética , Xenoinjertos , Humanos , Metaloproteinasa 2 de la Matriz/química , Ratones , Ratones Endogámicos C57BL , Imagen Óptica , Paclitaxel/administración & dosificación , Permeabilidad , Polímeros/química , Purinas/química , Pirazoles/química , Venenos de Escorpión/química , Transcitosis , Microambiente Tumoral
13.
Cytotechnology ; 68(2): 331-41, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25260543

RESUMEN

Nowadays, much effort is being devoted to detect new substances that not only significantly induce the death of tumor cells, but also have little side effect on normal cells. Our previous study showed that 2',4'-dihydroxy-6'-methoxy-3',5'-dimethylchalcone (DMC) exhibited significant cytotoxic potential with an IC50 value of 32.3 ± 1.13 µM against SMMC-7721 cells and could induce SMMC-7721 cells apoptosis. In the present study, we found that DMC was almost nontoxic to human normal liver L-02 and human normal fetal lung fibroblast HFL-1 cells as their IC50 values (111.0 ± 4.57 and 152.0 ± 4.83 µM for L-02 and HFL-1 cells, respectively) were much higher. To further explore the apoptotic mechanism of DMC, we investigated the role of the reactive oxygen species (ROS) in the apoptosis induced by DMC in SMMC-7721 cells. Our results suggested that the cytotoxicity and the generation of intracellular ROS were inhibited by N-acetylcysteine (NAC). Reversal of apoptosis in NAC pretreated cells indicated the involvement of ROS in DMC-induced apoptosis. The loss of mitochondrial membrane potential (ΔΨm) induced by DMC was significantly blocked by NAC. NAC also prevented the decrease of Caspase-3 and -9 activities, the increase of Bcl-2 protein expression and the decrease of p53 and PUMA protein expressions. Together, these results indicated that ROS played a key role in the apoptosis induced by DMC in human hepatoma SMMC-7721 cells.

14.
Zhongguo Zhong Yao Za Zhi ; 39(15): 2942-6, 2014 Aug.
Artículo en Chino | MEDLINE | ID: mdl-25423837

RESUMEN

OBJECTIVE: To study the in-vitro inducing apoptosis mechanism of human hepatoma SMMC-7721 cells by 2',4'-di- hydroxy-6'-methoxy-3',5'-dimethylchalcone (DMC), a chalcone compound from Cleistocalyx operculatus. METHOD: Quantitative DNA fragmentation assay was carried out to detect the effect of DMC of different concentrations on SMMC-7721 cells, according to the method of Sellins and Cohen with some modifications. Telomerase activities of the cells were determined by PCR-ELISA methods. The expression quantity of c-myc and hTERT mRNA were determined by semi-quantitative RT-PCR The effect of DMC on expression levels of cmyc and hTERT protein were measured by western blot. RESULT: The percentage of DNA fragmentation increased with notable concen- tration dependence, after treatment with DMC for 48 h. Compared with that of control group, the telomerase activity of the cells de- creased by (66.2 ± 2.1)% after 48 h treatment with 20 µmol x L(-1) DMC, the mRNA expression of c-myc and hTERT decreased by (67.3 ± 2.1)% and (64.4 ± 2.3)%, respectively, and the protein expression of c-myc and hTERT decreased by (69.6 ± 1.9)% and (71.3 ± 2.4)%, respectively. CONCLUSION: DMC can induce SMMC-7721 cell apoptosis and the apoptosis mechanism may be related to the decreased mRNA and protein expression of c-myc and hTERT.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Carcinoma Hepatocelular/patología , Chalconas/farmacología , Neoplasias Hepáticas/patología , Syzygium/química , Línea Celular Tumoral , Fragmentación del ADN/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Telomerasa/genética , Telomerasa/metabolismo
15.
Carbohydr Polym ; 89(4): 1131-7, 2012 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-24750924

RESUMEN

The response surface methodology was employed to study the extraction of polysaccharides from Scutellaria barbata D. Don. The quantitative effects of extraction temperature, time, number and ratio of water to raw material on yield of polysaccharides were investigated with Box-Behnken design. The experimental data were fitted to a second-order polynomial equation using multiple regression analysis and also analyzed using the appropriate statistical methods. By solving the regression equation and analyzing 3D plots, the optimum condition was at extraction temperature 70 °C, time 3h, numbers 3 and ratio of water to raw material 18.5 mL/g. Under these conditions, the experimental polysaccharides yield was 2.43±0.11%, which was in good agreement with the predicted value. The antioxidant activities of the polysaccharides were evaluated in vitro. A potential antioxidant activity of S. barbata polysaccharides provides a scientific basis for the use of this herb in traditional medicine as an antioxidant.


Asunto(s)
Antioxidantes , Medicamentos Herbarios Chinos/química , Extractos Vegetales/química , Polisacáridos , Scutellaria/química , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Polisacáridos/química , Polisacáridos/aislamiento & purificación
16.
Int J Biol Macromol ; 49(4): 466-70, 2011 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-21664928

RESUMEN

The extraction conditions of polysaccharides from Plantago asiatica L. seeds were investigated. Four parameters affecting the polysaccharides extraction, extraction times, water to sample, extraction temperature and single extraction time, were determined by orthogonal experiments. Under the optimized conditions, the polysaccharides yield of P. asiatica L. seeds was 2.467%. The antioxidant activities of the polysaccharides were investigated. The reducing power of the polysaccharides was dose dependent, and the reducing capacity of the polysaccharides was inferior to butylated hydroxytoluene, which is known to be a strong reducing agent. The scavenging rates of the polysaccharides on superoxide and 1,1-diphenyl-2-picrylhydrazyl radicals were 79.7% and 81.4%, at polysaccharides concentration of 0.75 mg/mL, respectively, a scavenging rates approximately similar to that of 0.75 mg/mL ascorbic acid (83.5% and 85.1%, respectively). Furthermore, it exhibited a moderate concentration-dependent ABTS radical scavenging activity, ferrous ion chelating potency and H(2)O(2) scavenging activity. The data obtained in the in vitro models clearly establish the antioxidant potency of the polysaccharides extracted from Semen Plantaginis.


Asunto(s)
Antioxidantes/farmacología , Plantago/química , Polisacáridos/aislamiento & purificación , Polisacáridos/farmacología , Semillas/química , Ácido Ascórbico/farmacología , Benzotiazoles/metabolismo , Compuestos de Bifenilo/metabolismo , Hidroxitolueno Butilado/metabolismo , Quelantes/farmacología , Fraccionamiento Químico , Ácido Edético/farmacología , Depuradores de Radicales Libres/farmacología , Peróxido de Hidrógeno/metabolismo , Oxidación-Reducción/efectos de los fármacos , Picratos/metabolismo , Ácidos Sulfónicos/metabolismo , Superóxidos/metabolismo
17.
J Pharm Pharmacol ; 59(4): 553-9, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17430639

RESUMEN

Two new flavonoids - 3'-formyl-4',6'-dihydroxy-2'-methoxy-5'-methylchalcone (FMC) and (2S)-8-formyl-5-hydroxy-7-methoxy-6-methylflavanone (FMF) - isolated from the buds of Cleistocalyx operculatus, were investigated for their antioxidant and anticancer activity. Total antioxidant activity and reducing ability were measured. 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and superoxide anion radical scavenging assays were carried out to evaluate the antioxidant potential of the two compounds. The antioxidant activity of the two compounds increased in a concentration-dependent manner. FMC and FMF at a concentration of 500 microM inhibited lipid peroxidation by 64.3 +/- 2.5% and 60.3 +/- 2.3%, respectively, an antioxidant activity approximately similar to that of 500 microM alpha-tocopherol (66.3 +/- 2.5%). Similarly, the effect of FMC and FMF on reducing power increased in a concentration-dependent manner. In DPPH radical scavenging assays, the IC50 values of FMC and FMF were 50.2 +/- 2.8 microM and 75.8 +/- 2.5 microM, respectively. Moreover, FMC and FMF scavenged the superoxide generated by the phenazine methosulfate (PMS)/reduced beta-nicotinamide adenine dinucleotide (NADH) nitroblue tetrazolium (NBT) system, with IC50 values of 56.3 +/- 2.3 microM and 317.5 +/- 2.9 microM, respectively. The anticancer activity of the two compounds were determined in five human cancer cell lines, SMMC-7721 (liver cancer), 8898 (pancreatic cancer), K562 (chronic leukaemia), HeLa (tumour of cervix uteri) and 95-D (high metastic lung carcinoma). FMC and FMF showed broad-spectrum anticancer activity against all the human cancer cell lines tested. The results obtained in the current study indicate that the two flavonoids could be a potential source of natural antioxidant and anticancer agents. To our knowledge, this is the first report on bioactivity of FMC and FMF.


Asunto(s)
Antineoplásicos/farmacología , Antioxidantes/farmacología , Chalconas/farmacología , Medicamentos Herbarios Chinos/farmacología , Flavanonas/farmacología , Flavonoides/farmacología , Myrtaceae/química , Antineoplásicos/aislamiento & purificación , Antioxidantes/aislamiento & purificación , Compuestos de Bifenilo , Línea Celular Tumoral/efectos de los fármacos , Chalconas/aislamiento & purificación , Relación Dosis-Respuesta a Droga , Medicamentos Herbarios Chinos/aislamiento & purificación , Flavanonas/aislamiento & purificación , Flavonoides/aislamiento & purificación , Flores , Depuradores de Radicales Libres , Humanos , Peroxidación de Lípido/efectos de los fármacos , Fitoterapia , Picratos , Plantas Medicinales , Superóxidos , alfa-Tocoferol/farmacología
18.
Leuk Res ; 29(8): 887-92, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15978939

RESUMEN

2',4'-Dihydroxy-6'-methoxy-3',5'-dimethylchalcone (DMC), isolated from the buds of Cleistocalyx operculatus, was investigated in its cytotoxicity and anti-proliferation on K562 cell line. Our results revealed that the IC50 was equal to 14.2+/-0.45 microM and the EC50 was 3.3+/-0.14 microM. Staining with Hoechst 33258 showed fragmentation and condensation of chromatin in the cells treated with 8 microM DMC for 48 h. Flow cytometric analysis was performed to determine hypodiploid cells. The results of flow cytometry assay indicated that the percentage of hypodiploid K562 cells was 76.15+/-3.22% after 48 h treatment with 16.0 microM DMC. The treatment resulted in the appearance of a hypodiploid peak (A0 region), probably due to the presence of apoptosing cells and/or apoptotic bodies with DNA content less than 2n. Western blot results illustrated that in the same dosage and incubation time, DMC could down-regulate the level of Bcl-2 protein and did not influence the expression of Bax protein. The resulting net effect could thus lead to a lower ratio of Bcl-2/Bax, which might be responsible for the DMC-induced apoptosis in K562 cells.


Asunto(s)
Apoptosis/efectos de los fármacos , Chalcona/análogos & derivados , Chalcona/farmacología , Leucemia Eritroblástica Aguda/tratamiento farmacológico , Línea Celular Tumoral , Núcleo Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Chalconas , Ensayo de Unidades Formadoras de Colonias , Diploidia , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Células K562 , Leucemia Eritroblástica Aguda/patología , Estructura Molecular , Proteínas Proto-Oncogénicas c-bcl-2/biosíntesis , Proteínas Proto-Oncogénicas c-bcl-2/efectos de los fármacos , Proteína X Asociada a bcl-2
19.
Cancer Chemother Pharmacol ; 56(1): 70-4, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15806415

RESUMEN

Previously we have shown that 2',4'-dihydroxy-6'-methoxy-3',5'-dimethylchalcone (DMC), which is isolated from the buds of Cleistocalyx operculatus, significantly inhibits the growth of human liver cancer SMMC-7721 cells and is able to induce apoptosis of SMMC-7721 cells in vitro. Here we report the antitumor effects of DMC in vivo, using a solid human tumor xenograft mouse model using human liver cancer SMMC-7721 cells. The average tumor weights in the control group and in mice injected with 150 mg/kg DMC were 1.42+/-0.11 g and 0.59+/-0.12 g, respectively. Flow cytometric analysis of the tumor cell population demonstrated an aneuploid peak (representing 33.60+/-0.80% of the total in mice injected with 150 mg/kg DMC). To our knowledge, this is the first time that chalcone compounds have been applied to a human tumor xenograft model.


Asunto(s)
Carcinoma/patología , Chalcona/análogos & derivados , Chalcona/farmacología , Neoplasias Hepáticas/patología , Myrtaceae/química , Extractos Vegetales/farmacología , Animales , Chalconas , Modelos Animales de Enfermedad , Ensayos de Selección de Medicamentos Antitumorales , Ratones , Trasplante Heterólogo
20.
Cancer Chemother Pharmacol ; 55(5): 447-52, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15666170

RESUMEN

Previously, we showed that 2',4'-dihydroxy-6'-methoxy-3',5'-dimethylchalcone (DMC), isolated from the buds of Cleistocalyx operculatus, significantly inhibited the growth of human liver cancer SMMC-7721 cells and could induce SMMC-7721 cells apoptosis in vitro. Here, we report the antitumor effects of DMC in vivo, using a solid human tumor xenograft model with a human liver cancer SMMC-7721 cell line. Our results revealed that the average tumor weight in a control group and a 150-mg/kg DMC injection group was 1.42+/-0.11 g and 0.59+/-0.12 g, respectively. Flow cytometric analysis of the tumor cell population demonstrated the existence of an aneuploid peak (representing 33.60+/-0.80% of the total in the 150-mg/kg DMC injection group). To our knowledge, this is the first time that chalcone compounds were applied to a human tumor xenograft model.


Asunto(s)
Chalcona/análogos & derivados , Chalcona/toxicidad , Neoplasias Hepáticas/tratamiento farmacológico , Ensayos Antitumor por Modelo de Xenoinjerto/métodos , Animales , Línea Celular Tumoral/efectos de los fármacos , Chalcona/farmacología , Chalcona/uso terapéutico , Chalconas , Citometría de Flujo , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos ICR
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