RESUMEN
Sesquiterpene lactone (SL) subtypes including hirsutinolide and cadinanolide have a controversial genesis. Metabolites of these classes are either described as natural products or as artifacts produced via the influence of solvents, chromatographic mobile phases, and adsorbents used in phytochemical studies. Based on this divergence, and to better understand the sensibility of these metabolites, different pH conditions were used to prepare semisynthetic SLs and evaluate the anti-inflammatory and antiproliferative activities. Therefore, glaucolide B (1) was treated with various Brønsted-Lowry and Lewis acids and bases-the same approach was applied to some of its derivatives-allowing us to obtain 14 semisynthetic SL derivatives, 10 of which are hereby reported for the first time. Hirsutinolide derivatives 7a (CC50 = 5.0 µM; SI = 2.5) and 7b (CC50 = 11.2 µM; SI = 2.5) and the germacranolide derivative 8a (CC50 = 3.1 µM; SI = 3.0) revealed significant cytotoxic activity and selectivity against human melanoma SK-MEL-28 cells when compared with that against non-tumoral HUVEC cells. Additionally, compounds 7a and 7c.1 showed strongly reduced interleukin-6 (IL-6) and nitrite (NOx) release in pre-treated M1 macrophages J774A.1 when stimulated with lipopolysaccharide. Despite the fact that hirsutinolide and cadinanolide SLs may be produced via plant metabolism, this study shows that acidic and alkaline extraction and solid-phase purification processes can promote their formation.
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Antineoplásicos , Sesquiterpenos , Humanos , Sesquiterpenos/farmacología , Sesquiterpenos/química , Antiinflamatorios/farmacología , Lactonas/farmacología , Lactonas/químicaRESUMEN
Senecio spp. is one of the most frequent plant-related poisonings in cattle. Its ingestion generates the disease seneciosis, characterized by hepatic damages. Liver biopsies and serum markers dosage are tools used in diagnosis; however, many breeding cattle are undiagnosed. MicroRNAs are non-coding RNA, stable in biological fluids. Their difference in expression levels may indicate the presence of the poisoning. We analyzed the miRNA profiling to identify potential diagnostic biomarkers for Senecio brasiliensis poisoning. The expression of miR-21, miR-885, miR-122, miR-181b, miR-30a, miR-378, and let-7 f were evaluated in the serum of exposed cattle. At least one histological change was found in liver and lower quantity of albumin and high AST and ALP were also detected. MiRNAs miR-30a, miR-378, miR-21, miR-885, and miR-122 presented significantly higher expression in intoxicated animals than in healthy animals. Furthermore, miR-122, miR-885, and, especially, miR-21 signatures demonstrated high sensitivity and specificity, with potential application for detecting poisoning.
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MicroARNs , Senecio , Animales , Biomarcadores , Bovinos , Hígado , MicroARNs/genética , Senecio/genéticaRESUMEN
Breast cancer is a major cause of death among women worldwide. Resistance to conventional therapies has been observed in HER2-positive breast cancer patients, indicating the need for more effective treatments. Small interfering RNA (siRNA) therapy is an attractive strategy against HER2-positive tumors, but its success depends largely on the efficient delivery of agents to target tissues. In this study, we prepared a magnetic hybrid nanostructure composed of iron oxide nanoparticles coated with caffeic acid and stabilized by layers of calcium phosphate and PEG-polyanion block copolymer for incorporation of siRNA. Transmission electron microscopy images showed monodisperse, neutrally charged compact spheres sized <100 nm. Dynamic light scattering and nanoparticle tracking analysis revealed that the nanostructure had an average hydrodynamic diameter of 130 nm. Nanoparticle suspensions remained stable over 42 days of storage at 4 and 25 °C. Unloaded caffeic acid-magnetic calcium phosphate (Caf-MCaP) nanoparticles were not cytotoxic, and loaded nanoparticles were successfully taken up by the HER2-positive breast cancer cell line HCC1954, even more so under magnetic guidance. Nanoparticles escaped endosomal degradation and delivered siRNA into the cytoplasm, inducing HER2 gene silencing.
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Neoplasias de la Mama , Sistemas de Liberación de Medicamentos , Campos Magnéticos , Nanopartículas , ARN Interferente Pequeño , Receptor ErbB-2 , Animales , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Femenino , Humanos , Ratones , Células 3T3 NIH , Nanopartículas/química , Nanopartículas/uso terapéutico , ARN Interferente Pequeño/química , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/farmacología , Receptor ErbB-2/antagonistas & inhibidores , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismoRESUMEN
BACKGROUND: Curry powder is a blend of spices that is extensively consumed worldwide and mainly in Central Asia. Its preparation is strictly related to each locality and, because of the health benefits of its constituents, eight commercial forms of this condiment were biologically and chemically investigated. This study aimed to compare their chemical profile as well as their anti-inflammatory, cytotoxic, and antiparasitic activities. RESULTS: Curry samples 1 and 7 inhibited leukocyte influx and myeloperoxidase activity, while only 7 was active on protein exudate and NOx species. 2, 6, and 8 displayed trypanocidal effect against Trypanosoma cruzi amastigote, whereas 6 showed antileishmanial activity on Leishmania amazonensis amastigote. 2, 6, and 8 also inhibited the growth of THP-1 cells used as the parasite's host. Among the cytotoxic samples (4 and 6), curry sample 6 induced apoptosis in MDA-MB-231 cells. Nevertheless, 4 and 6 were unselectively cytotoxic to non-tumoral and tumoral cells. The anti-inflammatory, cytotoxicity, and antiparasitic assays were respectively performed by carrageenan-induced pleurisy test, Alamar blue assay, and intracellular parasite-host cell model. Ultra-performance liquid chromatographic-electrospray ionization mass spectrometric data from the spices revealed both similar and different metabolites in their composition. CONCLUSION: The results obtained indicate that different formulations can contribute different health benefits as a result of their chemical composition. © 2018 Society of Chemical Industry.
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Antiinflamatorios/química , Antiinflamatorios/farmacología , Antiprotozoarios/química , Antiprotozoarios/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Especias/análisis , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Humanos , Leishmania/efectos de los fármacos , Leishmania/crecimiento & desarrollo , Pleuresia/tratamiento farmacológico , Pleuresia/inmunología , Polvos/química , Espectrometría de Masa por Ionización de Electrospray , Trypanosoma cruzi/efectos de los fármacos , Trypanosoma cruzi/crecimiento & desarrolloRESUMEN
Although inflammation is a biological phenomenon that exists to protect the host against infections and/or related problems, its unceasing activation results in the aggravation of several medical conditions. Imidazoles, whether natural or synthetic, are molecules related to a broad spectrum of biological effects, including anti-inflammatory properties. In this study, we screened eight novel small molecules of the imidazole class synthesized by our research group for their in vitro anti-inflammatory activity. The effect of the selected molecules was confirmed in an in vivo inflammatory model. We also analyzed whether the effects were caused by inhibition of nuclear factor kappa B (NF-κB) transcription factor transmigration. Of the eight imidazoles tested, methyl 1-allyl-2-(4-fluorophenyl)-5-phenyl-1H-imidazole-4-acetate (8) inhibited nitric oxide metabolites and pro-inflammatory cytokine (TNF-α, IL-6, and IL-1ß) secretion in J774 macrophages stimulated with LPS. It also attenuated leukocyte migration and exudate formation in the pleural cavity of mice challenged with carrageenan. Furthermore, imidazole 8 reverted the oxidative stress pattern triggered by carrageenan in the pleural cavity by diminishing myeloperoxidase, superoxide dismutase, catalase, and glutathione S-transferase activities and reducing the production of nitric oxide metabolites and thiobarbituric acid-reactive substances. Finally, these effects can be attributed, at least in part, to the ability of this compound to prevent NF-κB transmigration. In this context, our results demonstrate that imidazole 8 has promising potential as a prototype for the development of a new anti-inflammatory drug to treat inflammatory conditions in which NF-κB and oxidative stress play a prominent role. Graphical Abstract á .
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Antiinflamatorios/síntesis química , Diseño de Fármacos , Imidazoles/farmacología , Animales , Línea Celular , Imidazoles/síntesis química , Imidazoles/química , Ratones , FN-kappa B/antagonistas & inhibidores , Óxido Nítrico/metabolismo , Estrés Oxidativo/efectos de los fármacos , Relación Estructura-ActividadRESUMEN
Drugs containing the1,4-dihydropyridine (DHP) core have recently attracted attention concerning their antiparasitic effect against various species of Leishmania and Trypanosoma. This approach named drugs repositioning led to interesting results, which have prompted us to prepare 21 DHP's analogues. The 1,4-DHP scaffold was decorated with different function groups at tree points including the nitrogen atom (NH and N-phenyl), the aryl group attached to C-4 (various substituted aryl residues) and the carbon atoms 2 and 6 (bearing Ph or Me groups). Moreover, the products were evaluated for their cytotoxicity on three cancer and a non-tumoral cell lines. Only 6 of them were antiproliferative and their weak effect (CC50 comprised between 27 and 98µM) suggested these DHPs as good candidates against the intracellular amastigote forms of L. amazonensis and T. cruzi. L. amazonensis was sensitive to DHPs 5, 11 and 15 (IC50 values at 15.11, 45.70 and 53.13µM, respectively) while 12 of them displayed significant to moderate trypanocidal activities against T. cruzi. The best trypanocidal activities were obtained with compounds 2, 18 and 21 showing IC50 values at 4.95, 5.44, and 6.64µM, respectively. A part of the N-phenylated DHPs showed a better selectivity than their NH analogues towards THP-1 cells. 4-Chlorophenyl, 4-nitrophenyl and 3-nitrophenyl residues attached to the carbon atom 4 turned to be important sub-structures for the antitrypanosomal activity.
Asunto(s)
Bloqueadores de los Canales de Calcio/farmacología , Leishmania mexicana/efectos de los fármacos , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Animales , Bloqueadores de los Canales de Calcio/síntesis química , Línea Celular , Línea Celular Tumoral , Dihidropiridinas , Humanos , Células MCF-7 , Ratones , Células 3T3 NIH , Relación Estructura-Actividad , Tripanocidas/síntesis químicaRESUMEN
Metastasis is the main cause of cancer-related death and requires the development of effective treatments with reduced toxicity and effective anticancer activity. Gallic acid derivatives have shown significant biological properties including antitumoral activity as shown in a previous study with octyl gallate (G8) in vitro. Thus, the aim of this work was to evaluate the antimetastatic effect of free and solid lipid nanoparticle-loaded G8 in mice in a lung metastasis model. Animals inoculated with melanoma cells presented metastasis in lungs, which was significantly inhibited by treatment with G8 and solid lipid nanoparticle-loaded G8, named G8-NVM. However, G8-treated mice showed an increase in several toxicological parameters, which were almost completely circumvented by G8-NVM treatment. This study supports the need for pharmacological studies on new potential medicinal plants to treat cancer and can provide new perspectives on using nanotechnology to improve biological activities while decreasing the chemotherapy toxicological effects of anticancer drugs.
Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Ácido Gálico/análogos & derivados , Enfermedades Renales/inducido químicamente , Enfermedades Renales/prevención & control , Lípidos/administración & dosificación , Nanopartículas/administración & dosificación , Animales , Chlorocebus aethiops , Femenino , Ácido Gálico/administración & dosificación , Ácido Gálico/efectos adversos , Ácido Gálico/química , Lípidos/química , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundario , Melanoma Experimental/tratamiento farmacológico , Melanoma Experimental/metabolismo , Melanoma Experimental/patología , Ratones , Nanopartículas/química , Metástasis de la Neoplasia , Especies Reactivas de Oxígeno/metabolismo , Células VeroRESUMEN
Titanium dioxide nanoparticles (TiO2 NP) are present in several daily use products, and the risks associated with their bioaccumulation must be stablished. Thus, an evaluation of several toxicological-related effects was conducted after intraperitoneal injection of TiO2 NPs in mice. Mice were divided into two groups, which received 2 mg kg-1 day-1 of TiO2 NPs or vehicle saline. Assessments of body and organ weight as well as biochemical, hematological, and histopathological analyses were performed in order to evaluate adverse effects. The results showed that treatment resulted in an increased visceral and abdominal fat deposition, as well as a mononuclear inflammatory infiltrates in the abdominal fat tissue. The TiO2 NPs induced significant decrease in the weight gain and splenomegaly. Additionally, TiO2 NP-treated mice showed altered hematological parameters and significant liver injuries, which were characterized by histopathological and biochemical changes. Our results also indicated that TiO2 NPs were absorbed and significantly accumulated in the spleen, liver, and kidney. These results showed the ability of TiO2 NPs to infiltrate different organs and to induce inflammation and liver and spleen damage with visceral fat accumulation. The data obtained are useful for the governmental authorities to legislate and implement regulations concerning the use and the production of this kind of material that might be hazardous to the living beings, as well as to the environment.
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Tejido Adiposo/efectos de los fármacos , Inflamación/inducido químicamente , Grasa Intraabdominal/efectos de los fármacos , Nanopartículas del Metal/efectos adversos , Titanio/efectos adversos , Animales , Inyecciones Intraperitoneales , Masculino , Ratones , Titanio/administración & dosificaciónRESUMEN
Superparamagnetic iron oxide nanoparticles (SPIONS) were synthesized by thermal decomposition of an organometallic precursor at high temperature and coated with a bi-layer composed of oleic acid and methoxy-polyethylene glycol-phospholipid. The formulations were named SPION-PEG350 and SPION-PEG2000. Transmission electron microscopy, X-ray diffraction and magnetic measurements show that the SPIONs are near-spherical, well-crystalline, and have high saturation magnetization and susceptibility. FTIR spectroscopy identifies the presence of oleic acid and of the conjugates mPEG for each sample. In vitro biocompatibility of SPIONS was investigated using three cell lines; up to 100µg/ml SPION-PEG350 showed non-toxicity, while SPION-PEG2000 showed no signal of toxicity even up to 200µg/ml. The uptake of SPIONS was detected using magnetization measurement, confocal and atomic force microscopy. SPION-PEG2000 presented the highest internalization capacity, which should be correlated with the mPEG chain size. The in vivo results suggested that SPION-PEG2000 administration in mice triggered liver and kidney injury. FROM THE CLINICAL EDITOR: The potential use of superparamagnetic iron oxide nanoparticles (SPIONS) in the clinical setting have been studied by many researchers. The authors synthesized two types of SPIONS here and investigated the physical properties and biological compatibility. The findings should provide more data on the design of SPIONS for clinical application in the future.
Asunto(s)
Materiales Biocompatibles Revestidos/administración & dosificación , Nanopartículas de Magnetita/administración & dosificación , Polietilenglicoles/administración & dosificación , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Materiales Biocompatibles Revestidos/química , Compuestos Férricos/administración & dosificación , Compuestos Férricos/química , Humanos , Riñón/efectos de los fármacos , Hígado/efectos de los fármacos , Nanopartículas de Magnetita/química , Ratones , Ácido Oléico/química , Polietilenglicoles/química , Difracción de Rayos XRESUMEN
In this work in vivo experiments were conducted in order to characterize the biocompatibility of polyurethane nanoparticles (PU-NPs) after intraperitoneal (i.p.) and oral administration. Additionally, ex vivo assays were performed to assess human blood compatibility as well as in vitro assays to assess protein binding. Our results indicated that administration of three different concentrations of PU-NPs induced a significant increase in visceral fat accumulation after oral dosing. In addition, fat tissue of mice intraperitoneally treated with the highest concentration of nanoparticles showed diffuse mononuclear inflammatory infiltrate in the fat tissue. Histopathological assessment showed inflammatory infiltrate and hepatocyte vacuolization in the liver, inflammatory infiltration and vascular congestion in the lung and glomerular necrosis in the kidney. Hepatic enzymes related with liver function were significantly increased in both groups of mice treated with PU-NPs. The PU-NPs did not affect the human blood cells number as well as coagulation time but showed a susceptibility to bind in proteins commonly found in the blood stream. In addition, increased amounts of pro inflammatory cytokines in vivo, as well as ex vivo in human cells were observed. Further studies to establish the consequences of long-term exposure to PU-NPs are warranted.
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Inflamación/inducido químicamente , Nanopartículas/toxicidad , Poliuretanos/toxicidad , Administración Oral , Animales , Humanos , Inyecciones Intraperitoneales , Interleucina-6/sangre , Masculino , Ratones , Poliuretanos/administración & dosificación , Factor de Necrosis Tumoral alfa/sangreRESUMEN
ABSTRACTChlorogenic and caffeic acids are bioactive phenolic compounds present in Cecropia glaziovii Snethl., Urticaceae, products that have been used as analytical markers. This paper reports a chemometric study aimed at improving chromatographic performance for quantification of these markers by RP-HPLC. The organic to aqueous content ratio, the acid content of the mobile phase, and the elution method were analyzed using a Response Surface Methodology IV-Optimal design. The resolution between peaks, retention time, tailing and retention factors, number of theoretical plates and peak widths were evaluated. The optimized conditions were mathematically determined as (A) trifluoroacetic acid 0.05% (v/v), (B) 12% (v/v) acetonitrile and (C) increasing gradient. The method was considered specific, fast, precise, reliable and linear in the ranges of 1.0–200.0 and 2.5–100.0 µg/ml for the chlorogenic and caffeic acids, respectively. The adequate conditions to separate and quantify both phenolic acids in C. glaziovii products were demonstrated. Satisfactory resolution was achieved when compared to a previously published chromatographic method which is unable to separate the chlorogenic acid and an interfering compound presented under certain extractive conditions, demonstrating the importance of systematic studies, specifically when analyzing complex plant matrices.
RESUMEN
Acute lymphoblastic leukemia (ALL) is a malignant disorder caused by the proliferation of lymphoid progenitor cells and is the most common cancer in children. Cytotoxic nucleoside analogues are important chemotherapeutic agents, which are used in many cancers, including leukemias. In this study, we investigated the effects of the synthetic nucleoside analogue 1-(5,5,5-trichloro-2-methoxy-4-oxopenten-2-yl)-4-trichloromethyl-pyrimidin-2(1H)-one, named compound 3 or C3, on leukemia cell lines. The compound stimulated cell death by apoptosis, evidenced by DNA fragmentation, phosphatidylserine externalization, and caspase-3 activation. Compound 3 seemed to trigger several cell death pathways. The mitochondrial pathway was evidenced through a disturbance of mitochondrial membrane potential, strong cytochrome c liberation, decrease of antiapoptotic Bcl-2 protein expression, and caspase-9 activation. The C3 also induced caspase-8 and -12 activation, an increase in the intracellular calcium level, and an overproduction of reactive oxygen species. Increased caspase 8 activity suggests that the extrinsic pathway was activated and that the ROS production and enzyme activity alteration (glutathione S-transferase, glutathione peroxidase, catalase, and glutathione reductase) might be related to oxidative stress. Finally, the increase in calcium release, CHOP expression, and caspase-12 activity might characterize endoplasmic reticulum stress. Compound 3 was likewise cytotoxic to leukemic and melanoma human cell lines. Taken together, the results contribute to further understanding the new pyrimidine analogue as a potential chemotherapeutic drug or lead molecule.
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Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Pirimidinonas/farmacología , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Células Jurkat , Ratones , Estructura Molecular , Estrés Oxidativo/efectos de los fármacos , Pirimidinonas/síntesis química , Pirimidinonas/química , Relación Estructura-ActividadRESUMEN
Adenosine triphosphate-binding cassette subfamily G member 2 (ABCG2) plays a major role in cancer cell multidrug resistance, which contributes to low efficacy of chemotherapy. Chalcones were recently found to be potent and specific inhibitors, but unfortunately display a significant cytotoxicity. A cellular screening against ABCG2-mediated mitoxantrone efflux was performed here by flow cytometry on 54 chalcone derivatives from three different series with a wide panel of substituents. The identified leads, with submicromolar IC50 (half maximal inhibitory concentration) values, showed that the previously identified 2'-OH-4',6'-dimethoxyphenyl, as A-ring, could be efficiently replaced by a 2'-naphthyl group, or a 3',4'-methylenedioxyphenyl with lower affinity. Such a structural variability indicates 3polyspecificity of the multidrug transporter for inhibitors. At least two methoxyl groups were necessary on B-ring for optimal inhibition, but substitution at positions 3, 4, and 5 induced cytotoxicity. The presence of a large O-benzyl substituent at position 4 and a 2'-naphthyl as A-ring markedly decreased the cytotoxicity, giving a high therapeutic ratio, which constitutes a critical requirement for future in-vivo assays in animal models.
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Transportadoras de Casetes de Unión a ATP/antagonistas & inhibidores , Antineoplásicos/farmacología , Chalconas/farmacología , Proteínas de Neoplasias/antagonistas & inhibidores , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Transporte Biológico , Chalconas/administración & dosificación , Chalconas/química , Resistencia a Múltiples Medicamentos , Resistencia a Antineoplásicos , Citometría de Flujo , Células HEK293 , Humanos , Concentración 50 Inhibidora , Mitoxantrona/farmacocinética , Relación Estructura-ActividadRESUMEN
The hydrophobicity of some photosensitizers can induce aggregation in biological systems, which consequently reduces photodynamic activity. The conjugation of photosensitizers with nanocarrier systems can potentially be used to overcome this problem. The objective of this study was to prepare and characterise hypericin-loaded solid lipid nanoparticles (Hy-SLN) for use in photodynamic therapy (PDT). SLN were prepared using the ultrasonication technique, and their physicochemical properties were characterised. The mean particle size was found to be 153 nm, with a low polydispersity index of 0.28. One of the major advantages of the SLN formulation is its high entrapment efficiency (EE%). Hy-SLN showed greater than 80% EE and a drug loading capacity of 5.22% (w/w). To determine the photodynamic efficiency of Hy before and after encapsulation in SLN, the rate constants for the photodecomposition of two (1)O2 trapping reagents, DPBF and AU, were determined. These rate constants exhibited an increase of 60% and 50% for each method, respectively, which is most likely due to an increase in the lifetime of the triplet state caused by the increase in solubility. Hy-SLN presented a 30% increase in cell uptake and a correlated improvement of 26% in cytotoxicity. Thus, all these advantages suggest that Hy-loaded SLN has potential for use in PDT.
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Nanopartículas/química , Perileno/análogos & derivados , Fármacos Sensibilizantes a Radiaciones/química , Animales , Antracenos , Benzofuranos/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Humanos , Luz , Lípidos/química , Ratones , Perileno/química , Perileno/farmacología , Fotoquimioterapia , Fármacos Sensibilizantes a Radiaciones/farmacología , Oxígeno Singlete/química , Ácido Úrico/químicaRESUMEN
Based on classical colchicine site ligands and a computational model of the colchicine binding site on beta tubulin, two classes of chalcone derivatives were designed, synthesized and evaluated for inhibition of tubulin assembly and toxicity in human cancer cell lines. Docking studies suggested that the chalcone scaffold could fit the colchicine site on tubulin in an orientation similar to that of the natural product. In particular, a 3,4,5-trimethoxyphenyl ring adjacent to the carbonyl group appeared to benefit the ligand-tubulin interaction, occupying the same subcavity as the corresponding moiety in colchicine. Consistent with modeling predictions, several 3,4,5-trimethoxychalcones showed improved cytotoxicity to murine acute lymphoblastic leukemia cells compared with a previously described parent compound, and inhibited tubulin assembly in vitro as potently as colchicine. The most potent chalcones inhibited the growth of human leukemia cell lines at nanomolar concentrations, caused microtubule destabilization and mitotic arrest in human cervical cancer cells, and inhibited human breast cancer cell migration in scratch wound and Boyden chamber assays.
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Puntos de Control del Ciclo Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Chalconas/síntesis química , Chalconas/farmacología , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Chalconas/química , Relación Dosis-Respuesta a Droga , Humanos , Células Jurkat , Ratones , Modelos Químicos , Modelos Moleculares , Conformación Molecular , Estructura Molecular , Células 3T3 NIH , Polimerizacion/efectos de los fármacos , Tubulina (Proteína)/metabolismoRESUMEN
In this work, horseradish peroxidase (HRP) was immobilized on dimyristoylphosphatidylcholine (DMPC) bilayers supported on Au (111) by dithiotreitol (DTT) self-assembled monolayers and used as a nanostructured electrochemical biosensor to dopamine determination. The morphology of the phospholipid bilayers and the immobilization of HRP to these layers were characterized by atomic force microscopy (AFM). Square-wave voltammetry (SWV) experiments were done to investigate the performance of the HRP-modified electrode. The AFM images indicate that the enzyme is adsorbed at the external layer of the lipid bilayer and, although the electrical charges on the surface were not measured, the enzyme and phospholipids surface interaction occurs probably by electrostatic forces due to the pH used in the experiments. Interestingly, the present system can be used as one-shot sensor for the rapid detection of dopamine. The analytical performance of this system was linear for dopamine concentrations from 3.3 × 10â»5 to 1.3 × 10⻳ mol L⻹ (r = 0.9997) with a detection limit of 2.0 × 10â»6 mol L⻹. Our results indicate that the use of HRP-DMPC bilayer system may be useful not only in developing new nanostructured materials for technological purposes, but could be very useful in fundamental studies to investigate the interactions between different micro-and macromolecules, even with soluble proteins, and lipid membranes.
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Dopamina/análisis , Enzimas Inmovilizadas/química , Oro/química , Peroxidasa de Rábano Silvestre/química , Membrana Dobles de Lípidos/química , Reactores Biológicos , Biotecnología/instrumentación , Dimiristoilfosfatidilcolina , Ditiotreitol , Enzimas Inmovilizadas/metabolismo , Peroxidasa de Rábano Silvestre/metabolismo , Microscopía de Fuerza Atómica , Fosfolípidos/químicaRESUMEN
This study investigated the mechanism of cytotoxicity of octyl (G8) and dodecyl (G12) gallates in a murine melanoma cell line (B16F10). For this purpose, several methods to measure cell viability were used to determine if the cytotoxicity induced by these gallates corresponds to a general or an organelle-specific effect. Furthermore, the mechanisms related to apoptosis were examined, by studying the caspase-3 activity, oxidative stress, mitochondrial potential and the expression of anti- or proapoptotic proteins. When comparing the various methods of assessing cell viability, the tested gallates showed a higher cytotoxicity in the assay that indicates lysosomal activity, compared with the assays that indicate mitochondrial and ribosomal activities. Both gallates promoted the release of lactate dehydrogenase into the medium, indicating an effect on cell membrane integrity. The gallates also promoted cellular oxidative stress, mitochondrial depolarization and an increase in caspase-3 activity. Furthermore, the gallates induced an increase in proapoptotic (Bax) and a decrease in antiapoptotic (Bcl-2) proteins expression. Our results indicate that the apoptotic cell death induced by G8 and G12 in B16F10 cells involves lipid membrane damages, lysosomal and mitochondrial dysfunction, which was accompanied by alterations in apoptotic proteins expression and seems to be triggered by cellular oxidative stress.
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Apoptosis/efectos de los fármacos , Ácido Gálico/análogos & derivados , Estrés Oxidativo/efectos de los fármacos , Animales , Caspasa 3/metabolismo , Catalasa/metabolismo , Línea Celular Tumoral , Colorantes/metabolismo , ADN/análisis , Ácido Gálico/toxicidad , L-Lactato Deshidrogenasa/metabolismo , Melanoma , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Rojo Neutro/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Sales de Tetrazolio/metabolismo , Tiazoles/metabolismo , Proteína X Asociada a bcl-2/metabolismo , Receptor fas/metabolismoRESUMEN
Myeloperoxidase (MPO) is an important enzyme that catalyzes the reaction between hydrogen peroxide and chloride to generate hypochlorous acid, which oxidizes a range of biomolecules and has been associated with inflammatory diseases. The synthetic compounds N-phenylmaleimide (NFM) and 4-methyl-N-phenylmaleimide (Me-NFM) increased the MPO activity in vitro (of isolated enzyme and in isolated cells after animal treatment) and in vivo assays. MPO-induction may represent a good model system to investigate the molecular and cellular mechanisms of oxidative cell injury induced by activated neutrophils, and the interactions between damaging species involved in the respiratory burst.
Asunto(s)
Inflamación/fisiopatología , Maleimidas/farmacología , Peroxidasa/efectos de los fármacos , Animales , Modelos Animales de Enfermedad , Activación Enzimática/efectos de los fármacos , Masculino , Ratones , Neutrófilos/metabolismo , Estrés Oxidativo , Peroxidasa/metabolismo , Ratas , Ratas WistarRESUMEN
The objective of this study was to show a comparison of the antioxidant properties of aqueous and ethanolic extracts obtained from Baccharis articulata (Lam.) Pers., Baccharis trimera (Less.) DC., Baccharis spicata (Lam.) Baill. and Baccharis usterii Heering, Asteraceae, by several techniques covering a range of oxidant species and of biotargets. We have investigated the ability of the plant extracts to scavenge DPPH (1,1-diphenyl-2-picryl-hydrazyl) free radical, action against lipid peroxidation of membranes including rat liver microsomes and soy bean phosphatidylcholine liposomes by ascorbyl radical and peroxynitrite. Hydroxyl radical scavenger activity was measured monitoring the deoxyribose oxidation. The hypochlorous acid scavenger activity was also evaluated by the prevention of protein carbonylation and finally the myeloperoxidase (MPO) activity inhibition. The results obtained suggest that the Baccharis extracts studied present a significant antioxidant activity scavenging free radicals and protecting biomolecules from the oxidation. We can suggest that the supposed therapeutic efficacy of this plant could be due, in part, to these properties.
RESUMEN
The effect of melatonin was evaluated on three phosphatidylcholine-based membrane models. Changes in liposome dynamics were monitored by fluorescence, following the response of the probe merocyanine-540, as well as by differential scanning calorimetry (DSC). Langmuir monolayers were investigated using molecular area measurements, as well as by Brewster angle microscopy (BAM). Mica-supported bilayers were observed via atomic force microscopy (AFM). Fluorescence results demonstrating that melatonin increases the affinity between MC-540 and lipid molecules possibly because of an increase in the membrane fluidity in liposomes. DSC analyses showed that melatonin promoted a reduction in enthalpy in the lipid nonpolar chains. Melatonin also promoted an increase in the molecular area of Langmuir monolayers, as well as a decrease in membrane thickness. Consequently, melatonin appeared to induce re-ordering effects in liposome and Langmuir monolayers. AFM images of bilayers immobilized on mica suggested that melatonin induced a gel state predominance or a delay in the main phase transition. At experimental conditions, melatonin interacted actively with all membranes models tested and induced changes in their physico-chemical properties. The data presented here may contribute to the understanding of melatonin physiologic properties, as well as the development of therapeutic advanced systems, such as drug delivery systems and biosensors.