Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 20
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Biochim Biophys Acta Mol Basis Dis ; 1864(11): 3837-3846, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30251699

RESUMEN

Chemokine receptor CXCR4 was involved in the progression of breast cancer to a metastatic phenotype, leading to the major cause of death in patients. A more in-depth understanding of signaling mechanism underlying CXCR4 is critical to develop effective therapies toward metastasis. Recently, the role of antimicrobial peptide LL-37 in contributing to the metastasis of breast cancer cells was observed. Clinical analysis of data herein demonstrated for the first time that overexpression of LL-37 and CXCR4 co-existed in human primary breast tumors with lymph node metastases. Further study disclosed that forced expression of CXCR4 led to the enhancement of pro-migratory signaling and migration rate induced by LL-37 in breast cancer cells. Moreover, LL-37 affected tumor microenvironment including induction of migration of mesenchymal stem cells and CXCR4-dependent capillary-like tubule formation. Functional analysis showed that LL-37 induced the internalization of CXCR4 through approaching Glu268, the residue of CXCR4, independent of the binding pocket (Asp171, Asp262, and Glu288) for CXCR4 inhibitor AMD3100, signifying that LL-37 is a distinct agonist of CXCR4. These results suggest the reciprocal roles of LL-37 and CXCR4 in promoting breast cancer cell migration and provide new insight into the design of CXCR4 inhibitor for intervention of metastatic breast cancer.


Asunto(s)
Neoplasias de la Mama/patología , Catelicidinas/metabolismo , Movimiento Celular , Receptores CXCR4/metabolismo , Adulto , Anciano , Péptidos Catiónicos Antimicrobianos , Bencilaminas , Sitios de Unión , Mama/patología , Catelicidinas/química , Línea Celular Tumoral , Proliferación Celular , Ciclamas , Femenino , Regulación Neoplásica de la Expresión Génica , Compuestos Heterocíclicos/química , Compuestos Heterocíclicos/farmacología , Humanos , Metástasis Linfática , Células Madre Mesenquimatosas , Persona de Mediana Edad , Simulación del Acoplamiento Molecular , Unión Proteica/efectos de los fármacos , Receptores CXCR4/agonistas , Receptores CXCR4/antagonistas & inhibidores , Receptores CXCR4/química , Transducción de Señal , Microambiente Tumoral , Regulación hacia Arriba
2.
Int J Biol Macromol ; 81: 960-6, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26410813

RESUMEN

In the present study, a dimeric glucosamine binding lectin, designated as CHL, was purified from Phaseolus coccineus L. var. albonanus Bailey through three chromatographic steps. The molecular weight of CHL was approximately 66kDa. Its hemagglutinating activity toward rabbit erythrocytes was dependent on carbohydrates, especially glucosamine, and was stable at temperatures between 20 and 70°C, and at pH between 1 and 13. Intriguingly, further characterization showed that CHL served as a potent antioxidant to prevent erythrocytes from haemolysis induced by 2'-azobis (2-amidinopropane) dihydrochloride (AAPH) in a dose-dependent manner. Moreover, it exerted antitumor activity against human nasopharyngeal carcinoma CNE1 cells, hepatoma HepG2 cells, and breast cancer MCF7 cells but was devoid of antifungal activity. In addition, the CHL could bring about a significant dose-dependent increase in the production of mRNAs of pro-inflammatory cytokines including interferon-gamma and interleukin-2. These results suggest the potential therapeutic utility of CHL.


Asunto(s)
Antioxidantes/farmacología , Citocinas/metabolismo , Lectinas/farmacología , Phaseolus/química , Multimerización de Proteína , Amidinas/toxicidad , Animales , Proliferación Celular/efectos de los fármacos , Eritrocitos/efectos de los fármacos , Hemaglutinación/efectos de los fármacos , Hemólisis/efectos de los fármacos , Células Hep G2 , Humanos , Mediadores de Inflamación/metabolismo , Lectinas/aislamiento & purificación , Células MCF-7 , Masculino , Ratones Endogámicos BALB C , Peso Molecular , Conejos , Bazo/citología
3.
Phytomedicine ; 21(11): 1310-7, 2014 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-25172795

RESUMEN

PURPOSE: C-X-C chemokine receptor type 4 (CXCR4) signaling has been demonstrated to be involved in cancer invasion and migration; therefore, CXCR4 antagonist can serve as an anti-cancer drug by preventing tumor metastasis. This study aimed to identify the CXCR4 antagonists that could reduce and/or inhibit tumor metastasis from natural products. METHODS AND RESULTS: According to the molecular docking screening, we reported here silibinin as a novel CXCR4 antagonist. Biochemical characterization showed that silibinin blocked chemokine ligand 12 (CXCL12)-induced CXCR4 internalization by competitive binding to CXCR4, therefore inhibiting downstream intracellular signaling. In human breast cancer cells MDA-MB-231, which expresses high levels of CXCR4, inhibition of CXCL12-induced chemomigration can be found under silibinin treatment. Overexpression of CXCL12 sensitized MDA-MB-231 cells to the inhibition of silibinin, which was abolished by CXCR4 knockdown. The inhibition of silibinin was also observed in MCF-7/CXCR4 cells rather than MCF-7 cells that express low level of CXCR4. CONCLUSIONS: Our work demonstrated that silibinin is a novel CXCR4 antagonist that may have potential therapeutic use for prevention of tumor metastasis.


Asunto(s)
Movimiento Celular/efectos de los fármacos , Quimiocina CXCL12/metabolismo , Receptores CXCR4/antagonistas & inhibidores , Silimarina/farmacología , Línea Celular Tumoral , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Células MCF-7 , Simulación del Acoplamiento Molecular , Transducción de Señal/efectos de los fármacos , Silibina
4.
Biochem Pharmacol ; 89(3): 329-39, 2014 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-24637239

RESUMEN

All primary nasopharyngeal carcinoma (NPC) tumors contain hypoxic regions which are implicated in decreased local control and increased distant metastases, as well as resistance to chemotherapy in advanced NPC patients. One of the promising therapeutic approaches for NPC is to use drugs that can target hypoxic factors in tumors. In the present investigation, the type I ribosome inactivating protein α-momorcharin (α-MMC), isolated from seeds of the bitter gourd Momordica charantia, reduced cell viability and inhibited clonogenic formation of human NPC CNE2 and HONE1 cells under normoxia and cobalt chloride-induced hypoxia. By comparison, α-MMC exhibited only slight cytotoxicity on human nasopharyngeal epithelial NP69 cells under normoxia. Interestingly, α-MMC suppressed the expression levels of hypoxia-inducible factor 1-alpha (HIF1α) and vascular endothelial growth factor (VEGF) in hypoxic NPC, as well as the growth of human umbilical vein endothelial cells. Further study disclosed that α-MMC targeted endoplasmic reticulum and down-regulated unfolded protein response (UPR) in NPC cells. Moreover, α-MMC induced apoptosis in NPC cells in a dose- and time-dependent manner. It initiated mitochondrial- and death receptor-mediated apoptotic signaling in CNE2 cells, but there was hardly any effect on HONE1 cells. In addition, α-MMC brought about G0/G1 phase cell cycle arrest in CNE2 cells and S phase arrest in HONE1 cells. Collectively, α-MMC preferentially exhibited inhibitory effect on normoxic and hypoxic NPC cells partly by blocking survival signaling (e.g. HIF1α, VEGF and UPR), and triggering apoptotic pathways mediated by mitochondria or death receptor. These observations indicate the potential utility of α-MMC for prophylaxis and therapy of NPC.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Neoplasias Nasofaríngeas/tratamiento farmacológico , Oxígeno/farmacología , Proteínas Inactivadoras de Ribosomas/farmacología , Apoptosis/efectos de los fármacos , Carcinoma , Línea Celular Tumoral , Supervivencia Celular , Regulación hacia Abajo/efectos de los fármacos , Retículo Endoplásmico/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Mitocondrias/efectos de los fármacos , Carcinoma Nasofaríngeo , Oxígeno/química , Receptores de Muerte Celular/metabolismo , Transducción de Señal/efectos de los fármacos
5.
Appl Microbiol Biotechnol ; 98(8): 3475-94, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24562325

RESUMEN

Marine organisms including bacteria, fungi, algae, sponges, echinoderms, mollusks, and cephalochordates produce a variety of products with antifungal activity including bacterial chitinases, lipopeptides, and lactones; fungal (-)-sclerotiorin and peptaibols, purpurides B and C, berkedrimane B and purpuride; algal gambieric acids A and B, phlorotannins; 3,5-dibromo-2-(3,5-dibromo-2-methoxyphenoxy)phenol, spongistatin 1, eurysterols A and B, nortetillapyrone, bromotyrosine alkaloids, bis-indole alkaloid, ageloxime B and (-)-ageloxime D, haliscosamine, hamigeran G, hippolachnin A from sponges; echinoderm triterpene glycosides and alkene sulfates; molluscan kahalalide F and a 1485-Da peptide with a sequence SRSELIVHQR; and cepalochordate chitotriosidase and a 5026.9-Da antifungal peptide. The antiviral compounds from marine organisms include bacterial polysaccharide and furan-2-yl acetate; fungal macrolide, purpurester A, purpurquinone B, isoindolone derivatives, alterporriol Q, tetrahydroaltersolanol C and asperterrestide A, algal diterpenes, xylogalactofucan, alginic acid, glycolipid sulfoquinovosyldiacylglycerol, sulfated polysaccharide p-KG03, meroditerpenoids, methyl ester derivative of vatomaric acid, lectins, polysaccharides, tannins, cnidarian zoanthoxanthin alkaloids, norditerpenoid and capilloquinol; crustacean antilipopolysaccharide factors, molluscan hemocyanin; echinoderm triterpenoid glycosides; tunicate didemnin B, tamandarins A and B and; tilapia hepcidin 1-5 (TH 1-5), seabream SauMx1, SauMx2, and SauMx3, and orange-spotted grouper ß-defensin. Although the mechanisms of antifungal and antiviral activities of only some of the aforementioned compounds have been elucidated, the possibility to use those known to have distinctly different mechanisms, good bioavailability, and minimal toxicity in combination therapy remains to be investigated. It is also worthwhile to test the marine antimicrobials for possible synergism with existing drugs. The prospects of employing them in clinical practice are promising in view of the wealth of these compounds from marine organisms. The compounds may also be used in agriculture and the food industry.


Asunto(s)
Antifúngicos/aislamiento & purificación , Antivirales/aislamiento & purificación , Organismos Acuáticos/química , Productos Biológicos/aislamiento & purificación , Antifúngicos/farmacología , Antivirales/farmacología , Productos Biológicos/farmacología
6.
Arch Insect Biochem Physiol ; 85(3): 137-51, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24478049

RESUMEN

Chemosensory proteins (CSPs) are a group of small soluble proteins found so far exclusively in arthropod species. These proteins act in chemical communication and perception. In this study, a gene encoding the Type 1 CSP (BtabCSP1) from the agricultural pest Bemisia tabaci (whitefly) was analyzed to understand sequence variation and expression specificity in different biotypes. Sequence analysis of BtabCSP1 showed significant differences between the two genetically characterized biotypes, B and Q. The B-biotype had a larger number of BtabCSP1 mutations than the Q-biotype. Similar to most other CSPs, BtabCSP1 was more expressed in the head than in the rest of the body. One-step RT-PCR and qPCR analysis on total messenger RNA showed that biotype-Q had higher BtabCSP1 expression levels than biotype-B. Females from a mixed field-population had high levels of BtabCSP1 expression. The interaction of BtabCSP1 with the insecticide thiamethoxam was investigated by analyzing the BtabCSP1 expression levels following exposure to the neonicotinoid, thiamethoxam, in a time/dose-response study. Insecticide exposure increased BtabCSP1 expression (up to tenfold) at 4 and 24 h following 50 or 100 g/ml treatments.


Asunto(s)
Regulación de la Expresión Génica , Hemípteros/genética , Proteínas de Insectos/genética , Insecticidas/farmacología , Nitrocompuestos/farmacología , Oxazinas/farmacología , Tiazoles/farmacología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Hemípteros/efectos de los fármacos , Hemípteros/metabolismo , Proteínas de Insectos/metabolismo , Masculino , Datos de Secuencia Molecular , Neonicotinoides , Especificidad de Órganos , Filogenia , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Alineación de Secuencia , Caracteres Sexuales , Tiametoxam
7.
Artículo en Inglés | MEDLINE | ID: mdl-24302971

RESUMEN

Acetylcholinesterase inhibitors are prominent alternative in current clinical treatment for AD patients. Therefore, there is a continued need to search for novel AChEIs with good clinical efficacy and less side effects. By using our in-house natural product database and AutoDock Vina as a tool in docking study, we have identified twelve phytochemicals (emodin, aloe-emodin, chrysophanol, and rhein in Rhei Radix Et Rhizoma; xanthotoxin, phellopterin, alloisoimperatorin, and imperatorin in Angelicae dahuricae Radix; shikonin, acetylshikonin, isovalerylshikonin, and ß,ß-dimethylacrylshikonin in Arnebiae Radix) as candidates of AChEIs that were not previously reported in the literature. In addition to AChEI activity, a series of cell-based experiments were conducted for the investigation of their neuroprotective activities. We found that acetylshikonin and its derivatives prevented apoptotic cell death induced by hydrogen peroxide in human and rat neuronal SH-SY5Y and PC12 cells at 10 µM. We showed that acetylshikonin exhibited the most potent antiapoptosis activity through the inhibition of the generation of reactive oxygen species as well as protection of the loss of mitochondria membrane potential. Furthermore, we identified for the first time that the upregulation of heme oxygenase 1 by acetylshikonin is a key step mediating its antiapoptotic activity from oxidative stress in SH-SY5Y cells.

8.
Protein J ; 32(3): 208-15, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23475505

RESUMEN

In this study, a 60.8-kDa dimeric lectin was isolated from the Phaseolus vulgaris cv. jade bean and characterized. The lectin was bound on Blue Sepharose 6 and Q Sepharose and was finally purified by size exclusion chromatography on Superdex 200. Its hemagglutinating activity toward rabbit erythrocytes was dependent on divalent cations, especially calcium ions. Various carbohydrates tested were devoid of any effect on the hemagglutinating activity. The lectin was stable at pH between 4.5 and 9.4 and temperatures between 30 and 70 °C. It did not exert antifungal activity toward Valsa mali, Setosphaeria turcica, Mycosphaerella arachidicola, Fusarium oxysporum and Bipolaris maydis. The IC50 of the antiproliferative activity of the lectin toward MCF-7 human breast cancer cells was 174 µM. It did not inhibit proliferation of WRL-68 human normal embryonic hepatocytes. The lectin was dependent on calcium ions for hemagglutinating activity and possessed a blocked N-terminus. These two characteristics make the lectin unique among Phaseolus lectins.


Asunto(s)
Neoplasias de la Mama/fisiopatología , Calcio/metabolismo , Proliferación Celular/efectos de los fármacos , Inhibidores de Crecimiento/farmacología , Lectinas/farmacología , Phaseolus/química , Proteínas de Plantas/farmacología , Animales , Línea Celular Tumoral , Dimerización , Femenino , Inhibidores de Crecimiento/metabolismo , Humanos , Lectinas/química , Lectinas/aislamiento & purificación , Lectinas/metabolismo , Phaseolus/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/aislamiento & purificación , Proteínas de Plantas/metabolismo , Conejos
9.
Biochim Biophys Acta ; 1833(5): 987-96, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23274857

RESUMEN

Breast cancer is the second most common cancer with a high incidence rate worldwide. One of the promising therapeutic approaches on breast cancer is to use the drugs that target the estrogen receptor (ER). In the present investigation, marmorin, a type I ribosome inactivating protein from the mushroom Hypsizigus marmoreus, inhibited the survival of breast cancer in vitro and in vivo. It evinced more potent cytotoxicity toward estrogen receptor (ER)-positive MCF7 breast cancer cells than ER-negative MDA-MB-231 cells. Further study disclosed that marmorin undermined the expression level of estrogen receptor α (ERα) and significantly inhibited the proliferation of MCF7 cells induced by 17ß-estradiol. Knockdown of ERα in MCF7 cells significantly attenuated the inhibitory effect of marmorin on proliferation, suggesting that the ERα-mediated pathway was implicated in the suppressive action of marmorin on ER-positive breast cancer cells. Moreover, marmorin induced time-dependent apoptosis in both MCF7 and MDA-MB-231 cells. It brought about G2/M-phase arrest, mitochondrial membrane potential depolarization and caspase-9 activation in MCF7 cells, and to a lesser extent in MDA-MB-231 cells. Marmorin triggered the death receptor apoptotic pathway (e.g. caspase-8 activation) and endoplasmic reticulum stress (ERS, as evidenced by phosphorylation of PERK and IRE1α, cleavage of caspase-12, and up-regulation of CHOP expression) in both MCF7 and MDA-MB-231 cells. In summary, marmorin exhibited inhibitory effect on breast cancer partially via diminution of ERα and apoptotic pathways mediated by mitochondrial, death receptor and ERS. The results advocate that marmorin is a potential candidate for breast cancer therapy.


Asunto(s)
Neoplasias de la Mama , Receptor alfa de Estrógeno , Receptor beta de Estrógeno , Proteínas Fúngicas/administración & dosificación , Neoplasias Hormono-Dependientes , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Estrés del Retículo Endoplásmico/efectos de los fármacos , Estradiol/farmacología , Receptor alfa de Estrógeno/genética , Receptor alfa de Estrógeno/metabolismo , Receptor beta de Estrógeno/genética , Receptor beta de Estrógeno/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Células MCF-7 , Mitocondrias/metabolismo , Neoplasias Hormono-Dependientes/genética , Neoplasias Hormono-Dependientes/metabolismo , Regulación hacia Arriba/efectos de los fármacos , eIF-2 Quinasa/metabolismo
10.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 11): o1642, 2013 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-24454086

RESUMEN

In the title compound, C8H9ClN2O, the dihedral angle between the benzene ring and the methyl-amide substituent is 68.39 (11)°. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds, forming layers parallel to the ab plane.

11.
PLoS One ; 7(9): e41592, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22957017

RESUMEN

Breast cancer ranks as a common and severe neoplasia in women with increasing incidence as well as high risk of metastasis and relapse. Translational and laboratory-based clinical investigations of new/novel drugs are in progress. Medicinal plants are rich sources of biologically active natural products for drug development. The 27-kDa trichosanthin (TCS) is a ribosome inactivating protein purified from tubers of the Chinese herbal plant Trichosanthes kirilowii Maximowicz (common name Tian Hua Fen). In this study, we extended the potential medicinal applications of TCS from HIV, ferticide, hydatidiform moles, invasive moles, to breast cancer. We found that TCS manifested anti-proliferative and apoptosis-inducing activities in both estrogen-dependent human MCF-7 cells and estrogen-independent MDA-MB-231 cells. Flow cytometric analysis disclosed that TCS induced cell cycle arrest. Further studies revealed that TCS-induced tumor cell apoptosis was attributed to activation of both caspase-8 and caspase-9 regulated pathways. The subsequent events including caspase-3 activation, and increased PARP cleavage. With regard to cell morphology, stereotypical apoptotic features were observed. Moreover, in comparison with control, TCS- treated nude mice bearing MDA-MB-231 xenograft tumors exhibited significantly reduced tumor volume and tumor weight, due to the potent effect of TCS on tumor cell apoptosis as determined by the increase of caspase-3 activation, PARP cleavage, and DNA fragmentation using immunohistochemistry. Considering the clinical efficacy and relative safety of TCS on other human diseases, this work opens up new therapeutic avenues for patients with estrogen-dependent and/or estrogen-independent breast cancers.


Asunto(s)
Apoptosis , Neoplasias de la Mama/tratamiento farmacológico , Tricosantina/farmacología , Animales , Antineoplásicos/farmacología , Caspasa 3/metabolismo , Línea Celular Tumoral , Núcleo Celular/metabolismo , Proliferación Celular , Fragmentación del ADN , Activación Enzimática , Femenino , Humanos , Concentración 50 Inhibidora , Neoplasias Mamarias Animales/metabolismo , Medicina Tradicional China , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Extractos Vegetales/farmacología
12.
Expert Opin Pharmacother ; 13(12): 1695-705, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22716311

RESUMEN

INTRODUCTION: Invasive fungal infection (IFI) is a serious problem due to difficulties in early diagnosis and high mortality. Different approaches are adopted for the treatment and management of IFI, including prophylactic, empiric, preemptive and directed strategies. AREAS COVERED: This paper reviews the type of pharmacotherapy used for antifungal prophylaxis in infants with extremely low birth weights, pediatric patients with cardiac disease, preterm neonates, pediatric oncology patients, adult cancer patients with neutropenia, adult patients with hematologic malignancy, hematopoietic stem-cell transplantation recipients, organ transplant recipients, HIV-infected patients, immunosuppressed patients treated with moderate or high doses of corticosteroids, and patients with invasive fusariosis, candidemia, invasive candidiasis, systemic mycoses and immunocompromised patients. EXPERT OPINION: Azole drugs are the drugs most often used in cost-effective antifungal prophylaxis of patients with conditions such as immunodeficiency and cancer, which render them highly susceptible to IFI. Fluconazole is the most outstanding example. However, there are many azoles with different pharmacological characteristics that the physician can choose from. Echinocandins have favorable characteristics that make them useful for treating Candida infections. Antibodies, or their engineered derivatives directed against cell-wall polysaccharides and glycopeptides, and some protein epitopes of Candida albicans, appear to be a promising novel approach for prophylaxis against Candida infection and deserve further in-depth investigations.


Asunto(s)
Antifúngicos/uso terapéutico , Micosis/prevención & control , Azoles/uso terapéutico , Humanos , Huésped Inmunocomprometido
13.
Acta Biochim Biophys Sin (Shanghai) ; 44(4): 307-15, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22321825

RESUMEN

A 5.4-kDa antifungal peptide, with an N-terminal sequence highly homologous to defensins and inhibitory activity against Mycosphaerella arachidicola (IC(50)= 3 µM), Setospaeria turcica and Bipolaris maydis, was isolated from the seeds of Phaseolus vulgaris cv. brown kidney bean. The peptide was purified by employing a protocol that entailed adsorption on Affi-gel blue gel and Mono S and finally gel filtration on Superdex 75. The antifungal activity of the peptide against M. arachidicola was stable in the pH range 3-12 and in the temperature range 0°C to 80°C. There was a slight reduction of the antifungal activity at pH 2 and 13, and the activity was indiscernible at pH 0, 1, and 14. The activity at 90°C and 100°C was slightly diminished. Deposition of Congo red at the hyphal tips of M. arachidicola was induced by the peptide indicating inhibition of hyphal growth. The lack of antiproliferative activity of brown kidney bean antifungal peptide toward tumor cells, in contrast to the presence of such activity of other antifungal peptides, indicates that different domains are responsible for the antifungal and antiproliferative activities.


Asunto(s)
Antifúngicos/farmacología , Péptidos/farmacología , Phaseolus/química , Proteínas de Plantas/farmacología , Secuencia de Aminoácidos , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Ascomicetos/efectos de los fármacos , Ascomicetos/crecimiento & desarrollo , Rojo Congo , Defensinas/química , Defensinas/aislamiento & purificación , Defensinas/farmacología , Electroforesis en Gel de Poliacrilamida , Concentración de Iones de Hidrógeno , Concentración 50 Inhibidora , Microscopía Confocal , Microscopía Fluorescente , Datos de Secuencia Molecular , Peso Molecular , Péptidos/química , Péptidos/aislamiento & purificación , Proteínas de Plantas/química , Proteínas de Plantas/aislamiento & purificación , Estabilidad Proteica , Análisis de Secuencia de Proteína , Homología de Secuencia de Aminoácido , Temperatura
14.
Arch Toxicol ; 86(2): 293-304, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21969071

RESUMEN

A 20-kDa Kunitz-type trypsin-chymotrypsin inhibitor, Bauhinia purpurea trypsin inhibitor (BPLTI), has been isolated from the seeds of B. purpurea L. by using liquid chromatography procedures that involved ion exchange chromatography on Sp-Sepharose and Mono S and gel filtration on Superdex 75. BPLTI demonstrated protease inhibitory activities of 7226 BAEE units/mg and 65 BTEE units/mg toward trypsin and α-chymotrypsin, respectively. BPLTI was relatively thermal (0-60°C) and pH (3-10) stable and its activity could be decreased by dithiothreitol treatment. BPLTI exhibited a wide spectrum of anti-proliferative and pro-apoptotic activities especially on human hepatocellular carcinoma Hep G2 cells. However, it was devoid of a significant antiproliferative effect on immortal human hepatic WRL 68 cells. We show here that BPLTI stimulates apoptosis in Hep G2 cells, including (1) evoking DNA damage including the production of chromatin condensation and apoptotic bodies; (2) induction of cell apoptosis/necrosis; (3) mitochondrial membrane depolarization; and (4) increasing the production of cytokines. Taken together, our findings show for the first time that purified protease inhibitor from B. purpurea L. seeds is a promising candidate for the treatment of human hepatocellular carcinoma.


Asunto(s)
Antineoplásicos/farmacología , Bauhinia/química , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Extractos Vegetales/farmacología , Antineoplásicos/aislamiento & purificación , Apoptosis/efectos de los fármacos , Células Hep G2 , Humanos , Extractos Vegetales/aislamiento & purificación , Semillas/química , Inhibidores de Tripsina/aislamiento & purificación , Inhibidores de Tripsina/farmacología , Células Tumorales Cultivadas
15.
Cancer Prev Res (Phila) ; 5(1): 109-21, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21933914

RESUMEN

The incidence of nasopharyngeal carcinoma (NPC) remains high in endemic regions, including southern China, northern Africa, and North America. One of the promising therapeutic approaches on NPC is drug screening from natural products, such as components from traditional Chinese medicine. In this study, the antitumor activity of Momordica charantia lectin (MCL), a type II ribosome inactivating protein from bitter gourd, on NPC was investigated. MCL evinced potent cytotoxicity toward NPC CNE-1 (IC(50) = 6.9) and CNE-2 (IC(50) = 7.4) cells but minimally affected normal NP 69 cells. Further investigation disclosed that MCL induced apoptosis, DNA fragmentation, G(1)-phase arrest, and mitochondrial injury in both types of NPC cells. The reduction of cyclin D1 and phosphoretinoblastoma (Rb) protein expression contributed to arrest at G(1)-phase of the cell cycle. These events were associated with regulation of mitogen-activated protein kinases (MAPK; including p38 MAPK, JNK, and ERK) phosphorylation and promoted downstream nitric oxide (NO) production. Concurrent administration of the p38 MAPK inhibitor SB-203580 significantly diminished NO production and lethality of MCL toward NPC cells. Further studies revealed that MCL increased cytochrome c release into the cytosol, activated caspases-8, -9, and -3, and enhanced production of cleaved PARP, subsequently leading to DNA fragmentation and apoptosis. Finally, an intraperitoneal injection of MCL (1.0 mg/kg/d) led to an average of 45% remission of NPC xenograft tumors subcutaneously inoculated in nude mice. This is the first article that unveils the potential of a type II RIP, MCL, for prevention and therapy of NPC.


Asunto(s)
Antineoplásicos/farmacología , Carcinoma/tratamiento farmacológico , Lectinas/química , Momordica charantia/metabolismo , Neoplasias Nasofaríngeas/tratamiento farmacológico , Extractos Vegetales/metabolismo , Extractos Vegetales/farmacología , Proteínas Inactivadoras de Ribosomas/química , Animales , Línea Celular Tumoral , Fragmentación del ADN , Ensayos de Selección de Medicamentos Antitumorales/métodos , Humanos , Técnicas In Vitro , Concentración 50 Inhibidora , Sistema de Señalización de MAP Quinasas , Potenciales de la Membrana , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Fosforilación , Inducción de Remisión
16.
Zhonghua Yu Fang Yi Xue Za Zhi ; 46(11): 999-1003, 2012 Nov.
Artículo en Chino | MEDLINE | ID: mdl-23363920

RESUMEN

OBJECTIVE: To investigate the effectiveness of psychosocial services provided by social workers in reducing dropout rate and increasing treatment dosage in methadone maintenance treatment (MMT) users. METHODS: From May in 2009 to April in 2010, 300 MMT users were recruited from three MMT clinics in Guangzhou, and were randomly allocated into the intervention group and the control groups. The control group (152 cases) received standard MMT services while the intervention group (148 cases) received additional services provided by social workers. Methadone dosage, dropout rate, perceptions toward MMT etc. were compared between the two groups. RESULTS: The 1-month dropout rate of the control and intervention groups were 19.7% (30/152) and 6.8% (10/148) (P < 0.05) respectively; the 6-month dropout rate of the control and intervention groups were 75.5% (115/152) and 50.7% (75/148) (P < 0.05) respectively. The intervention group had higher average treatment dosage than the control group ((56.0 ± 21.2) vs (64.4 ± 23.1) ml/d, (58.0 ± 24.0) vs (66.1 ± 26.6) ml/d, P < 0.05). At 1-month and 6-month, the intervention group had higher scores of MMT-related perception ((1.26 ± 0.68) vs (1.84 ± 0.95), (1.55 ± 0.83) vs (2.44 ± 1.23), P < 0.05), self-efficacy of maintenance ((3.68 ± 1.33) vs (4.20 ± 1.05), (3.80 ± 1.38) vs (4.43 ± 0.79), P < 0.05) and satisfaction toward MMT((4.08 ± 0.54) vs (4.15 ± 0.60), (4.01 ± 0.67) vs (4.31 ± 0.64), P < 0.05) as compared to the control group. The reverse was true for the score of negative experiences ((1.05 ± 0.86) vs (0.96 ± 0.92), (1.46 ± 0.87) vs (1.11 ± 1.07), P < 0.05). CONCLUSION: The psychosocial interventions provided by social workers were effective in reducing dropout rate, increasing treatment dosage and improving cognitions of MMT users.


Asunto(s)
Metadona/uso terapéutico , Tratamiento de Sustitución de Opiáceos , Servicio Social , Adulto , Femenino , Dependencia de Heroína/tratamiento farmacológico , Humanos , Masculino , Metadona/administración & dosificación , Cooperación del Paciente , Centros de Tratamiento de Abuso de Sustancias , Resultado del Tratamiento
17.
J Agric Food Chem ; 59(18): 10232-8, 2011 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-21830763

RESUMEN

A 30 kDa antifungal protein was purified from red cabbage ( Brassica oleracea ) seeds. It exhibited a molecular mass and N-terminal amino acid sequence disinct from those of previously isolated Brassica antifungal proteins. The protocol used entailed ion exchange chromatography on Q-Sepharose and SP-Sepharose followed by fast protein liquid chromatography on Mono S. The protein hindered mycelial growth in Mycosphaerella arachidicola (with an IC50=5 µM), Setospaeria turcica, and Bipolaris maydis. It also inhibited the yeast Candida albicans with an IC50=96 µM. It exerted its antifungal action by permeabilizing the fungal membrane as evidenced by staining with Sytox green. The antifungal activity was stable from pH 3 to 11 and from 0 to 65 °C. It manifested antibacterial activity against Pseudomonas aeruginosa (IC50=53 µM). Furthermore, after 48 h of culture, it suppressed proliferation of nasopharyngeal cancer and hepatoma cells with IC50=50 and 90 µM, respectively.


Asunto(s)
Antibacterianos/farmacología , Antifúngicos/farmacología , Antineoplásicos Fitogénicos/farmacología , Brassica/química , Proteínas de Plantas/farmacología , Semillas/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Fungicidas Industriales/farmacología , Humanos , Micelio/efectos de los fármacos , Micelio/crecimiento & desarrollo , Proteínas de Plantas/aislamiento & purificación , Pseudomonas aeruginosa/efectos de los fármacos
18.
Arch Toxicol ; 85(12): 1551-63, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21445585

RESUMEN

We describe here the purification and characterization of a new Phaseolus vulgaris lectin that exhibits selective toxicity to human hepatoma Hep G2 cells and lacks significant toxicity on normal liver WRL 68 cells. This polygalacturonic acid-specific lectin (termed BTKL) was purified from seeds of P. vulgaris cv. Blue tiger king by liquid chromatography techniques. The 60-kDa dimeric lectin showed strong and broad-spectrum hemagglutinating activity toward human, rabbit, rat, and mouse erythrocytes. Bioinformatic analysis unveils substantial N-terminal sequence similarity of BTKL to other Phaseolus lectins. Among a number of tumor cells tested, BTKL exhibits potent anti-Hep G2 activity which is associated with (1) induction of DNA fragmentation, (2) production of apoptotic bodies and chromatin condensation, (3) triggering of cell apoptosis and necrosis, and (4) depolarization of mitochondrial membrane (low ΔΨm). Furthermore, BTKL could induce inducible nitric oxide synthase (iNOS) expression and subsequent nitric oxide production in vitro in mouse macrophages, which may contribute to its antitumor activity. In addition, BTKL could bring about a significant dose-dependent increase in the production of mRNAs of proinflammatory cytokines including interleukin-1 beta, interleukin-2, tumor necrosis factor alpha, and interferon-gamma. In sum, the antitumor activity and mechanism of BTKL provided here suggest that it has potential therapeutic value for human liver cancer.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Lectinas/farmacología , Neoplasias Hepáticas/tratamiento farmacológico , Phaseolus/química , Animales , Antineoplásicos Fitogénicos/administración & dosificación , Antineoplásicos Fitogénicos/aislamiento & purificación , Apoptosis/efectos de los fármacos , Línea Celular , Línea Celular Tumoral , Cromatografía Liquida , Citocinas/metabolismo , Fragmentación del ADN , Relación Dosis-Respuesta a Droga , Eritrocitos/efectos de los fármacos , Eritrocitos/metabolismo , Células Hep G2 , Humanos , Lectinas/administración & dosificación , Lectinas/aislamiento & purificación , Neoplasias Hepáticas/patología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Óxido Nítrico/metabolismo , Conejos , Ratas , Ratas Sprague-Dawley , Especificidad de la Especie
19.
J Biomed Sci ; 16: 16, 2009 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-19272183

RESUMEN

BACKGROUND: Dihydroartemisinin (DHA), a semi-synthetic derivative of artemisinin, isolated from the traditional Chinese herb Artemisia annua, is recommended as the first-line anti-malarial drug with low toxicity. DHA has been shown to possess promising anticancer activities and induce cancer cell death through apoptotic pathways, although the molecular mechanisms are not well understood. METHODS: In this study, cell counting kit (CCK-8) assay was employed to evaluate the survival of DHA-treated ASTC-a-1 cells. The induction of apoptosis was detected by Hoechst 33258 and PI staining as well as flow cytometry analysis. Collapse of mitochondrial transmembrane potential (DeltaPsim) was measured by dynamic detection under a laser scanning confocal microscope and flow cytometry analysis using Rhodamine123. Caspase-3 activities measured with or without Z-VAD-fmk (a broad spectrum caspase inhibitor) pretreatment by FRET techniques, caspase-3 activity measurement, and western blotting analysis. RESULTS: Our results indicated that DHA induced apoptotic cell death in a dose- and time-dependent manner, which was accompanied by mitochondrial morphology changes, the loss of DeltaPsim and the activation of caspase-3. CONCLUSION: These results show for the first time that DHA can inhibit proliferation and induce apoptosis via caspase-3-dependent mitochondrial death pathway in ASTC-a-1 cells. Our work may provide evidence for further studies of DHA as a possible anticancer drug in the clinical treatment of lung adenocarcinoma.


Asunto(s)
Antimaláricos/farmacología , Apoptosis/efectos de los fármacos , Artemisininas/farmacología , Caspasa 3/metabolismo , Línea Celular Tumoral/efectos de los fármacos , Pulmón/citología , Clorometilcetonas de Aminoácidos/metabolismo , Apoptosis/fisiología , Forma de la Célula , Supervivencia Celular/efectos de los fármacos , Inhibidores de Cisteína Proteinasa/metabolismo , Activación Enzimática , Transferencia Resonante de Energía de Fluorescencia , Humanos , Neoplasias Pulmonares/metabolismo , Medicina Tradicional China , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/ultraestructura
20.
Ying Yong Sheng Tai Xue Bao ; 18(4): 859-64, 2007 Apr.
Artículo en Chino | MEDLINE | ID: mdl-17615885

RESUMEN

The volatiles of field cotton plant at its squaring stage were analyzed qualitatively and quantitatively under treatments of mechanical injury (treatment A), cotton bollworm (CBW) injury (treatment B), CBW plus CBW larva injury (treatment C), and salicylic acid (SA) inducement (treatment D). The volatiles were gathered in an automatic circle system, absorbed by Tenax-TA column, and analyzed with GC-MS system. About 30 kinds of volatiles were qualitatively identified, including terpenoids, aliphatic compounds, aromatic compounds, 3-hexanone, 2-hexanone, 3-hexanol, a-pinene, beta-pinene, beta-myrcene, propenoic acid, butyl ester, acetic acid, pentyl ester, acetic acid, butyl ester, butanoic acid, 3-methyl-, ethyl ester, benzaldehyde, acetophenone and 1, 3, 6-octatriene,3 ,7-dimethyl, etc., and a total of 10 primary volatiles were detected quantitatively. The results showed that both the kinds and the contents of the volatiles were notably higher in treatments B and C than in the control. It was noteworthy that 1, 3, 6-octatriene 3, 7-dimethyl was only found in treatments B and C, i. e., it only occurred in the cotton plants injured by CBW. There were no significant differences in the kinds and contents of the volatiles between treatment A and the control. Similar to CBW injury, SA inducement also enhanced the release of cotton plant volatiles.


Asunto(s)
Ácidos Grasos Volátiles/análisis , Gossypium/metabolismo , Aceites Volátiles/análisis , Terpenos/análisis , Gossypium/efectos de los fármacos , Gossypium/parasitología , Volatilización
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...