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Carcinogenic N-nitroso compounds, especially N-nitroso dimethylamine, increase the risk of gastric cancer development. Cytochrome P450-2E1 metabolizes this compound, thus generating an oxidant microenvironment. We aimed to evaluate in gastric adenocarcinoma cells if its effect on CYP2E1 and ROS affects signaling pathways associated with gastric cancer oncogenesis. The impact of N- nitroso dimethylamine upon CYP2E1 and ROS activation/secretion was evaluated by the DCFDA assay protocol, TER measurements, Stat3, pSTAT3, ERK1/2, and pERK1/2 expression, claudins-1 and -6 expression, and finally mRNA values of IL-1ß IL-6, IL-8 and TNFα. Our results showed that exposure to N- N-nitroso dimethylamine disrupts the regulation of Stat3 and Erk1/2, alters the expression of claudin-1 and claudin-6 tight junction proteins, and increases the secretion of pro-inflammatory cytokines. These alterations induce a continuous local inflammatory process, an event identified as a gastric cancer promoter. In summary, N-nitroso dimethylamine can disrupt cell mechanisms associated with gastric cancer oncogenesis.
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The Neotropical genus Heteromphrale Kröber, 1937, so far known from Argentina, Chile and Uruguay, is recorded for the first time from Peru based on the description of a new species, Heteromphrale illapa sp. nov. from Moquegua. An update to the key to the known species is provided, as well as a distribution map.
El género neotropical Heteromphrale Kröber, 1973, hasta ahora solo conocido para Argentina, Chile y Uruguay, es reportado por primera vez para Perú con base en la descripción de una especie nueva, Heteromphrale illapa sp. nov. de Moquegua. Además, se proporciona una actualización de la clave de identificación para las especies conocidas, así como un mapa de distribución.
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Aberrant expression of the tight junction protein claudin 6 (CLDN6) is a hallmark of gastric cancer progression. Its expression is regulated by the cAMP response element-binding protein (CREB). In gastric cancer induced by Helicobacter pylori (H. pylori) there is no information regarding what transcription factors induce/upregulate the expression of CLDN6. We aimed to identify whether CREB and Yin Yang1 (YY1) regulate the expression of CLDN6 and the site where they bind to the promoter sequence. Bioinformatics analysis, H. pylori lipopolysaccharide (LPS), YY1 and CREB silencing, Western blot, luciferase assays, and chromatin immunoprecipitation experiments were performed using the stomach gastric adenocarcinoma cell line AGS. A gen reporter assay suggested that the initial 2000 bp contains the regulatory sequence associated with CLDN6 transcription; the luciferase assay demonstrated three different regions with transcriptional activity, but the -901 to -1421 bp region displayed the maximal transcriptional activity in response to LPS. Fragment 1279-1421 showed CREB and, surprisingly, YY1 occupancy. Sequential Chromatin Immunoprecipitation (ChIP) experiments confirmed that YY1 and CREB interact in the 1279-1421 region. Our results suggest that CLDN6 expression is regulated by the binding of YY1 and CREB in the 901-1421 enhancer, in which a non-described interaction of YY1 with CREB was established in the 1279-1421 region.
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Adenocarcinoma , Helicobacter pylori , Neoplasias Gástricas , Humanos , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/genética , Lipopolisacáridos/farmacología , Factor de Transcripción YY1/genéticaRESUMEN
Cancer is a leading cause of death worldwide. Understanding the functional mechanisms associated with metabolic reprogramming, which is a typical feature of cancer cells, is key to effective therapy. CD38, primarily a NAD + glycohydrolase and ADPR cyclase, is a multifunctional transmembrane protein whose abnormal overexpression in a variety of tumor types is associated with cancer progression. It is linked to VEGFR2 mediated angiogenesis and immune suppression as it favors the recruitment of suppressive immune cells like Tregs and myeloid-derived suppressor cells, thus helping immune escape. CD38 is expressed in M1 macrophages and in neutrophil and T cell-mediated immune response and is associated with IFNγ-mediated suppressor activity of immune responses. Targeting CD38 with anti-CD38 monoclonal antibodies in hematological malignancies has shown excellent results. Bearing that in mind, targeting CD38 in other nonhematological cancer types, especially carcinomas, which are of epithelial origin with specific anti-CD38 antibodies alone or in combination with immunomodulatory drugs, is an interesting option that deserves profound consideration.
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Gastric cancer is a heterogeneous disease that represents 5% to 10% of all new cancer cases worldwide. Advances in histological diagnosis and the discovery of new genes have admitted new genomic classifications. Nevertheless, the bioinformatic analysis of gastric cancer databases has favored the detection of specific differentially expressed genes with biological significance. Claudins, a family of proteins involved in tight junction physiology, have emerged as the key regulators of cellular processes, such as growth, proliferation, and migration, associated with cancer progression. The expression of Claudin-9 in the gastric cancer tissue has been linked to poor prognosis, however, its transcriptional and epigenetic regulations demand a more comprehensive analysis. Using the neural network promoter prediction, TransFact, Uniprot-KB, Expasy-SOPMA, protein data bank, proteomics DB, Interpro, BioGRID, String, and the FASTA protein sequence databases and software, we found the following: (1) the promoter sequence has an unconventional structure, including different transcriptional regulation elements distributed throughout it, (2) GATA 4, GATA 6, and KLF5 are the key regulators of Claudin-9 expression, (3) Oct1, NF-κB, AP-1, c-Ets-1, and HNF-3ß have the higher binding affinity to the CLDN9 promoter, (4) Claudin-9 interacts with cell differentiation and development proteins, (5) CLDN9 is highly methylated, and (6) Claudin-9 expression is associated with poor survival. In conclusion, Claudin-9 is a protein that should be considered a diagnostic marker as its gene promoter region binds to the transcription factors associated with the deregulation of cell control, enhanced cell proliferation, and metastasis.
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Non-small lung cell carcinoma has a high morbidity and mortality rates. The elective treatment for stage III and IV is cisplatinum that conveys serious toxic side effects. Vanadium compounds are metal molecules with proven antitumor activity that depends on its valence. Therefore, a better understanding of the mechanism of action of vanadium compounds is required. The aim of our study was to investigate the mechanisms of cell death induced by sodium metavanadate (NaVO3 [V(+5)]) and vanadyl sulfate (VOSO4 [(+4)]), both of which have reported apoptotic-inducing activity. We exposed the A549 cell line to various concentrations (0-100 µM) and to different exposure times to each compound and determined the cell viability and expression of caspases, reactive oxygen species (ROS) production, Bcl2, Bax, FasL and NO. Our results showed that neither compounds modified the basal expression of caspases or pro- and anti-apoptotic proteins. The only change observed was the 12- and 14-fold significant increase in ROS production induced by NaVO3 and VOSO4 , respectively, at 100 µm concentrations after 48 hours. Our results suggest that classical apoptotic mechanisms are not related to the cell death induced by the vanadium compounds evaluated here, and showed that the higher ROS production was induced by the [(+4)] valence compound. It is possible that the difference will be secondary to its higher oxidative status and thus higher ROS production, which leads to higher cell damage. In conclusion, our results suggest that the efficacy of the cell death mechanisms induced by vanadium compounds differ depending on the valence of the compound.
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Compuestos de Vanadio/toxicidad , Células A549 , Caspasas/genética , Muerte Celular/efectos de los fármacos , Humanos , Fosfatidilserinas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Vanadatos/toxicidadRESUMEN
Gastric carcinogenesis has been associated to H. pylori virulence factors that induce a chronic inflammation process. Lipopolysaccharides play a role in chronic inflammatory responses via TLR2- and TLR4-dependent signaling pathways. Similarly, cellular invasiveness, metastatic potential and prognosis are usually associated to claudin-4, -6, -7 and -9 expression in gastric carcinogenesis. Therefore, the aim of this study was to determine if H. pylori LPS exerts an influence on carcinogenesis-related claudin expression and if it was directly regulated through the TLR2 pathway. Human antrum gastric adenocarcinoma AGS cells exposed or not to H. pylori LPS were used. Polyclonal anti-claudin-4, -6, -7 and -9, anti-TLR2, anti-pERK1/2 as well as rabbit monoclonal anti-pNFκB p65 and mouse monoclonal anti-CdX2 were used. ERK1/2 inhibitor UO126 and STAT3 inhibitor Stattic were also used. Western blot, immunofluorescence and confocal experiments were performed in whole cells as well as total protein, nuclear and cell membrane fractions. The results showed that H. pylori LPS increased the expression of TLR2 in a time dependent bi-phasic manner (<12 and >12h exposure). Immunofluorescence using AGS monolayers corroborated the double phase TLR2 expression mainly on the cell membrane but a detectable signal was also determined in the cytoplasm of the cells. Activation of NFkB was downstream and depended on TLR2 expression as a statistically significant increase in pNFkB, that followed a pattern highly similar to the TLR2 expression was observed on the cell membrane fraction. The increase in TLR2 expression was accompanied by dramatically increased claudin-4 expression in cultures exposed from 30m to 8h to LPS. Increased expression of claudin-6, -7 and -9 also increases in >12h LPS exposure times. The increase in claudins expression was also dependent on NFkB activation. The results also showed an increase in pSTAT3 that followed a bi-phasic pattern that began 30min after stimulation and was compatible with the increase in TLR2 expression. The expression of the claudin-4 related CDX2 transcription factor did not followed the biphasic pattern. The results also showed that claudin-4 expression was STAT3 dependent whereas claudin-6, 7 and 9 expressions was ERK1/2 dependent. Our results suggest that H. pylori LPS induces TLR2 expression in the AGS cells, and that the longer the exposure to LPS, the greater the expression of TLR2 in the cell membrane. Consequently the expression of claudin-4, -6, -7 and -9 also increases.
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Adenocarcinoma/inmunología , Claudina-4/metabolismo , Claudinas/metabolismo , Infecciones por Helicobacter/inmunología , Helicobacter pylori/inmunología , Neoplasias Gástricas/inmunología , Carcinogénesis , Línea Celular Tumoral , Claudina-4/genética , Claudinas/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Lipopolisacáridos/inmunología , Sistema de Señalización de MAP Quinasas , Factor de Transcripción STAT3/metabolismo , Receptor Toll-Like 2/metabolismo , TranscriptomaRESUMEN
The aging brain shows biochemical and morphological changes in the dendrites of pyramidal neurons from the limbic system associated with memory loss. Prolame (N-(3-hydroxy-1,3,5 (10)-estratrien-17ß-yl)-3-hydroxypropylamine) is a non-feminizing aminoestrogen with antithrombotic activity that prevents neuronal deterioration, oxidative stress, and neuroinflammation. Our aim was to evaluate the effect of prolame on motor and cognitive processes, as well as its influence on the dendritic morphology of neurons at the CA1, CA3, and granule cells of the dentate gyrus (DG) regions of hippocampus (HP), and medium spiny neurons of the nucleus accumbens (NAcc) of aged mice. Dendritic morphology was assessed with the Golgi-Cox stain procedure followed by Sholl analysis. Prolame (60 µg/kg) was subcutaneously injected daily for 60 days in 18-month-old mice. Immediately after treatment, locomotor activity in a new environment and recognition memory using the Novel Object Recognition Task (NORT) were evaluated. Prolame-treated mice showed a significant increase in the long-term exploration quotient, but locomotor activity was not modified in comparison to control animals. Prolame-treated mice showed a significant increase in dendritic spines density and dendritic length in neurons of the CA1, CA3, and DG regions of the HP, whereas dendrites of neurons in the NAcc remained unmodified. In conclusion, prolame administration promotes hippocampal plasticity processes but not in the NAcc neurons of aged mice, thus improving long-term recognition memory. Prolame could become a pharmacological alternative to prevent or delay the brain aging process, and thus the emergence of neurodegenerative diseases that affect memory.
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Particulate matter air pollution has considerably increased during the last decades; vanadium is a transition element adhered to this particulate matter, and the combustion of fossil fuels is the main source in the atmosphere. It has been reported that air pollution and specifically vanadium exposure increases the probability of suffering arrhythmias; however the biological mechanism of such a relationship remains unknown. It has been established that a diminished presence of N-Cadherin alters the Connexin-43 arrangement, and the consequent altered presence of these proteins predisposes to ventricular heart rate problems. We analyzed myocardial histology and the expression of N-Cadherin and Connexin-43 by immunohistochemistry in mouse that inhaled vanadium. Our results showed a significant and progressive reduction in both N-Cadherin and Connexin-43, as well as the presence of meganucleus; myofibrils disruption, and clumping in the exposed groups were also observed. Our findings add more information about a possible explanation for the arrythmogenic effect observed in dwellers of cities with high particulate matter atmospheric pollution.
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Cadherinas/metabolismo , Conexina 43/metabolismo , Corazón/efectos de los fármacos , Miocardio/metabolismo , Material Particulado/toxicidad , Vanadio/toxicidad , Contaminación del Aire , Animales , Inmunohistoquímica , Masculino , RatonesRESUMEN
OBJECTIVE: Endometriosis is linked to altered cell proliferation and stem cell markers c-kit/stem cell factor (SCF) in ectopic endometrium. Our aim was to investigate whether c-kit/SCF also plays a role in eutopic endometrium. DESIGN: Eutopic endometrium obtained from 35 women with endometriosis and 25 fertile eumenorrheic women was analyzed for in situ expression of SCF/c-kit, Ki67, RAC-alpha serine/threonine-protein kinase (Akt), phosphorylated RAC-alpha serine/threonin-protein kinase (pAkt), Glycogen synthase kinase 3 beta (GSK3ß), and phosphorylated glycogen synthase kinase 3 beta (pGSK3ß), throughout the menstrual cycle. RESULTS: Expression of Ki67 and SCF was higher in endometriosis than in control tissue (P < .05) and greater in secretory rather than proliferative (P < .01) endometrium in endometriosis. Expression of c-kit was also higher in endometriosis although similar in both phases. Expression of Akt and GSK3ß was identical in all samples and cycle phases, whereas pAkt and pGSK3ß, opposed to control tissue, remained overexpressed in the secretory phase in endometriosis. CONCLUSION: Unceasing cell proliferation in the secretory phase of eutopic endometriosis is linked to deregulation of c-kit/SCF-associated signaling pathways.
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Proliferación Celular , Endometriosis/enzimología , Endometrio/enzimología , Glucógeno Sintasa Quinasa 3/análisis , Proteínas Proto-Oncogénicas c-akt/análisis , Adulto , Biopsia , Estudios de Casos y Controles , Endometriosis/patología , Endometriosis/fisiopatología , Endometrio/metabolismo , Endometrio/patología , Femenino , Glucógeno Sintasa Quinasa 3 beta , Humanos , Inmunohistoquímica , Antígeno Ki-67/metabolismo , Fosforilación , Proteínas Proto-Oncogénicas c-kit/metabolismo , Transducción de Señal , Adulto JovenRESUMEN
Two hallmarks of Alzheimer diseases are the continuous inflammatory process, and the brain deposit of Amyloid b (Aß), a cytotoxic protein. The intracellular accumulation of Aß(25-35) fractions, in the absence of Heat Shock proteins (Hsps), could be responsible for its cytotoxic activity. As, pro-inflammatory mediators and nitric oxide control the expression of Hsps, our aim was to investigate the effect of Aß(25-35) on the concentration of IL-1ß, TNF-α and nitrite levels, and their relation to pHSF-1, Hsp-60, -70 and -90 expressions, in the rat C6 astrocyte cells. Interleukin-specific ELISA kits, immunohistochemistry with monoclonal anti-Hsp and anti pHSF-1 antibodies, and histochemistry techniques, were used. Our results showed that Aß25-35 treatment of C6 cells increased, significantly and consistently the concentration of IL-1ß, TNF-α and nitrite 3 days after initiating treatment. The immunoreactivity of C6 cells to Hsp-70 reached its peak after 3 days of treatment followed by an abrupt decrease, as opposed to Hsp-60 and -90 expressions that showed an initial and progressive increase after 3 days of Aß(25-35) treatment. pHSF-1 was identified throughout the experimental period. Nevertheless, progressive and sustained cell death was observed during all the treatment times and it was not caspase-3 dependent. Our results suggest that Hsp-70 temporary expression serves as a trigger to inhibit casapase-3 pathway and allow the expression of Hsp-60 and -90 in C6 astrocytoma cells stimulated with Aß(25-35).
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Péptidos beta-Amiloides/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas HSP70 de Choque Térmico/metabolismo , Fragmentos de Péptidos/metabolismo , Factores de Transcripción/metabolismo , Péptidos beta-Amiloides/farmacología , Animales , Astrocitoma , Muerte Celular , Citocinas/análisis , Citocinas/metabolismo , Factores de Transcripción del Choque Térmico , Inflamación/metabolismo , Óxido Nítrico/análisis , Óxido Nítrico/metabolismo , Fragmentos de Péptidos/farmacología , Fosforilación , Ratas , Células Tumorales CultivadasRESUMEN
BACKGROUND: Hepatitis C virus (HCV) infection usually results in long-term viremia. Entry of HCV into the hepatocyte requires claudin-1, -6, -9 and occludin. The efficacy of Pegylated interferon-α (PEG-IFN) treatment against HCV infection increased when ribavirin (RBV) was added to the therapeutic scheme. Our aim was to investigate if PEG-IFN plus RBV regulate claudin expression. MATERIAL AND METHODS: HepG2, Huh-7 and Huh-7.5 cells were treated with PEG-IFN-α2a or α2b and/or RBV at different times before obtaining the cytosolic, membrane and cytoskeletal fractions. Claudin-1, 3, 4, 6, and 9, E-cadherin and occludin expression was evaluated by Western blot analysis. Transepithelial electrical resistance (TER) was also determined. RESULTS: Claudin-1, 3, 4, 6, E-cadherin and occludin are constitutively expressed mainly in HepG2 cell membrane. Claudin-1 and E-cadherin cell membrane expression diminished after exposure to PEGIFNα2b (50 ng) + RBV(50 µg); the maximal decrease was observed with 200 ng of PEG-IFNα2b + 200 µg of RBV. The effect was less intense with PEG-IFNα2a. The inhibition of claudin-1 and E-cadherin expression in Huh-7 and Huh-7.5 cells was only observed with 200 ng of PEG-IFNα2b + 200 µg of RBV. TER diminished marginally in the HCV containing hepatoma cells with 200 ng of PEG-IFNα2b + 200 µg of RBV. Claudin-1 mRNA expression level was not affected by the combined treatment. CONCLUSION: The increased therapeutic efficacy of the PEG-IFNα2b plus RBV treatment could be secondary to the inhibition of claudin-1 and E-cadherin cell membrane expression.
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Antivirales/farmacología , Cadherinas/metabolismo , Claudina-1/metabolismo , Hepatocitos/efectos de los fármacos , Interferón-alfa/farmacología , Polietilenglicoles/farmacología , Ribavirina/farmacología , Antígenos CD , Western Blotting , Cadherinas/genética , Regulación hacia Abajo , Impedancia Eléctrica , Células Hep G2 , Hepatocitos/metabolismo , Hepatocitos/patología , Humanos , Interferón alfa-2 , ARN Mensajero/metabolismo , Proteínas Recombinantes/farmacología , Uniones Estrechas/efectos de los fármacos , Uniones Estrechas/metabolismo , Factores de TiempoRESUMEN
Alzheimer's disease (AD) is a neurodegenerative disorder caused by the deposition of the amyloid-beta peptide (Aß) in senile plaques and cerebral vasculature. Its neurotoxic mechanisms are associated with the generation of oxidative stress and reactive astrogliosis that cause neuronal death and memory impairment. Estrogens reduce the rate of Azheimer's disease because of their antioxidant activity. Prolame (N-(3-hydroxy-1,3,5(10)-estratrien-17ß-yl)-3-hydroxypropylamine) is an aminoestrogen with estrogenic and antithrombotic effects. In our study we evaluated the role of prolame on Aß(25-35)-caused oxidative stress, reactive astrogliosis, and impairment of spatial memory(.) The Aß(25-35) (100 µM/µl) or vehicle was injected into the CA1 subfield of the hippocampus of the rat. The subcutaneous injection of prolame (400 µl, 50 nM) or sesame oil (400 µl) started 1 day before the Aß(25-35) injection and was continued for another 29 days. The results showed a significant impairment of spatial memory evident 30 days after the Aß(25-35) injection. The prolame treatment significantly reduced spatial-memory impairment and decreased lipid peroxidation, reactive oxygen species, and reactive gliosis. It also restored the eNOS and nNOS expression to normal levels. In conclusion the aminoestrogen prolame should be considered as an alternative in the treatment of Alzheimer's disease.
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Estrenos/farmacología , Discapacidades para el Aprendizaje/tratamiento farmacológico , Trastornos de la Memoria/tratamiento farmacológico , Fármacos Neuroprotectores/farmacología , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/fisiopatología , Péptidos beta-Amiloides/toxicidad , Animales , Modelos Animales de Enfermedad , Estrenos/administración & dosificación , Hipocampo/efectos de los fármacos , Hipocampo/fisiopatología , Discapacidades para el Aprendizaje/fisiopatología , Peroxidación de Lípido/efectos de los fármacos , Masculino , Trastornos de la Memoria/fisiopatología , Fármacos Neuroprotectores/administración & dosificación , Óxido Nítrico Sintasa de Tipo I/metabolismo , Óxido Nítrico Sintasa de Tipo III/metabolismo , Estrés Oxidativo/efectos de los fármacos , Fragmentos de Péptidos/toxicidad , Ratas , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismoRESUMEN
HCV-Ag-specific TH17 cells secrete IL17, a cytokine involved in autoimmune diseases and regulated by IL10 and TGF-b. 5-12% of patients with chronic HCV infection have hypothyroidism. We evaluated the role of these cytokines in this patients by determining serum concentration of TsH, T3, free T4, IL2, IL10, IL12, IL17, TGF-b, anti-TG, TPO, CCP, GBM, and cardiolipin antibodies in 87 chronically noninterferon treated HCV-infected patients. 20 patients (group A) had elevated TsH values (>5 µUI/ml) whereas the remaining 67 (group B) had normal values. The percentage of anti-TPO, TG, GBM, and cardiolipin antibodies in group A patients (33%, 41%, 5% and 5%, resp.) as well as IL17, IL2 and TGF-b concentrations (25 ± 23 pg/ml, 643 ± 572 pg/ml, and 618 ± 221 pg/ml, resp.) were significantly higher than group B. Abnormal Th17 regulation mediated by IL-2 and low TGF-b concentrations is associated with hypothyroidism in chronically-infected HCV patients.
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Air pollution by suspended particles has become a worldwide health problem. The main sources of these particles are fossils and additives combustion. Mn enters the body through inhalation, but part of the particles accesses contact with tongue's posterior surface where lingual tonsils and lingual papillae are placed. We decided to explore in a mouse model, the impact that the deposit of inhaled Mn has on the tongue's surface. Atrophy of the lingual tonsil, filiform papillae, as well as the swelling of taste buds in fungiform papillae, were the predominant changes. Ferropenic anemia is associated with the changes described and could be related to the interference of Mn in iron metabolism and riboflavin absorption. More research should be done to explore the participation of suspended particles trapped in the oral cavity in toxicology of Mn or other inhaled pollutants.
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Manganeso/toxicidad , Material Particulado/toxicidad , Lengua/efectos de los fármacos , Lengua/ultraestructura , Administración por Inhalación , Animales , Atrofia , Modelos Animales de Enfermedad , Masculino , Manganeso/administración & dosificación , Ratones , Microscopía Electrónica de Rastreo , Tonsila Palatina/efectos de los fármacos , Tonsila Palatina/ultraestructura , Material Particulado/administración & dosificación , Papilas Gustativas/efectos de los fármacos , Papilas Gustativas/ultraestructuraRESUMEN
Previous reports from our laboratory informed in mice an increase in platelets in blood, and megakaryocytes in spleen and bone marrow after vanadium inhalation. This element has become important in recent years because of its increased presence as an air pollutant. With this precedent, we evaluate the ultrastructural modifications in MKs from the spleen and bone marrow in our mouse experimental model. Mice inhaled 0.02 M V(2)O(5) 1 h twice a week for 12 weeks. Tissues were processed for transmission electron microscopy. Results indicate an increase in the size and cytoplasmic granular content, as well as nuclear changes in MKs of exposed mice, changes which correlate with the time of exposure. Modifications in MKs described here suggest that inhaled vanadium induce megakaryocytic maturation, a raise in its granules content and demarcation membrane systems, which may lead to a rise in circulating platelet production and an increased risk for thromboembolic events.
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Médula Ósea/efectos de los fármacos , Megacariocitos/efectos de los fármacos , Bazo/efectos de los fármacos , Oligoelementos/toxicidad , Vanadio/toxicidad , Animales , Médula Ósea/patología , Gránulos Citoplasmáticos/efectos de los fármacos , Gránulos Citoplasmáticos/ultraestructura , Exposición por Inhalación , Masculino , Megacariocitos/ultraestructura , Ratones , Microscopía Electrónica de Transmisión , Bazo/patologíaRESUMEN
Statins have antiproliferative and anti-tumoral effects in MCF-7 cells. We determined the effect of statins upon MCF-7 cell cycle, toxicity, cell death, reactive oxygen species (ROS) production and mitochondrial membrane potential. Fluvastatin, simvastatin and atorvastatin inhibited cell proliferation. Antiproliferation was associated with a decrease in the DNA synthesis and a cell cycle arrest in the G1 and G2/M phases. A loss in the mitochondrial membrane potential was observed with fluvastatin. Statins induced increase in ROS production that was associated with cell death, which was abrogated by the antioxidant NAC. Our results suggest that the cytotoxic effect observed is mediated by an oxidative stress.
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Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/patología , Ciclo Celular/efectos de los fármacos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Estrés Oxidativo/efectos de los fármacos , Acetilcisteína/farmacología , Antioxidantes/farmacología , Atorvastatina , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Membrana Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Replicación del ADN/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ácidos Grasos Monoinsaturados/farmacología , Femenino , Fluvastatina , Ácidos Heptanoicos/farmacología , Humanos , Indoles/farmacología , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Necrosis , Pirroles/farmacología , Especies Reactivas de Oxígeno/metabolismo , Simvastatina/farmacologíaRESUMEN
BACKGROUND: Recent findings indicate that atherosclerosis, a chronic inflammatory process, might start during childhood. Nevertheless, the expression of inflammation-related molecules of endothelial cell isolated from healthy neonates with a strong family history of myocardial infarction (SFHMI) has been rarely analyzed. METHODS: Human umbilical vein endothelial cells (HUVECs) from children with SFHMI were assessed for the expression of CD40 and CD40L, in the presence of TNF-alpha and oxLDL. The intracellular content of CD80, CXCL8 and tissue factor by HUVECs stimulated with a CD40 agonist monoclonal antibody as well as monocytes/lymphocyte adhesion to TNF-alpha-stimulated HUVECs was also evaluated. RESULTS: The basal expression of CD40 and CD40L was higher in SFHMI-positive HUVECs in comparison to controls. TNF-alpha and oxLDL upregulated the expression of CD40 and CD40L in SFHMI versus control HUVECs (p<0.001). The intracellular expression of CXCL8, tissue factor and CD80 was also higher than in controls, and the adhesion of lymphocyte- and monocyte-like cells augmented upon TNF-alpha stimulation. CONCLUSIONS: It is possible that the modifications observed in the SFHMI-positive HUVECs, all of them relevant to the atherosclerosis process, may lead to early inflammatory reactions, thus contributing to the premature initiation of atherosclerotic lesions in these children.
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Antígenos CD40/metabolismo , Ligando de CD40/metabolismo , Células Endoteliales/inmunología , Células Endoteliales/metabolismo , Lipoproteínas LDL/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Adhesión Celular , Humanos , Recién Nacido , Inflamación/inmunología , Inflamación/metabolismo , Interleucina-8/metabolismo , Linfocitos/fisiología , Monocitos/fisiología , Infarto del Miocardio/inmunología , Infarto del Miocardio/metabolismo , Tromboplastina/metabolismo , Venas UmbilicalesRESUMEN
Ceramide is regarded as an important cellular signal for the induction of cell death. We have previously shown that ceramide induces the death of cervical tumor cells without biochemical and morphological markers of apoptosis. The mechanisms by which ceramide induces cell death are not understood, therefore we evaluated the effect of C6-ceramide, a synthetic cell-permeable analog of endogenous ceramides, in signaling pathways involved in the oxidative stress of three cervical human papilloma virus cancer cell lines. Reactive oxygen species production was determined by fluorescent 2,7-dichlorofluorescein, nitrite concentration by the Griess reaction (as an indirect measure of nitric oxide production), mitochondrial membrane potential by staining with Rh123, reduced-glutathione concentration by high-pressure liquid chromatography, nuclear factor-kappaB translocation by electrophoretic mobility shift assay, inhibitory protein of nuclear factor-kappaB expression by Western blot and cell death by a poly-caspases fluorochrome-labeled inhibitors of caspases apoptosis assay. C6-ceramide induced early and late apoptosis, which was associated with an increase in reactive oxygen species and nitric oxide production, a loss in mitochondrial membrane potential, an increase in nuclear factor-kappaB translocation, and a decrease in reduced glutathione concentration. C6-ceramide did not modify the expression of inhibitory protein of nuclear factor-kappaB and its antiproliferative effect was not abrogated by Bay 11-7082, an inhibitory protein of nuclear factor-kappaB kinase inhibitor. Our results suggest that oxidative stress might participate in the ceramide-induced damage to human papilloma virus cervical cancer cells.
Asunto(s)
Ceramidas/farmacología , Glutatión/metabolismo , FN-kappa B/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/virología , Apoptosis/efectos de los fármacos , Inhibidores de Caspasas , Línea Celular Tumoral , Inhibidores Enzimáticos/farmacología , Femenino , Células HeLa , Humanos , Potenciales de la Membrana/efectos de los fármacos , Membranas Mitocondriales/metabolismo , FN-kappa B/antagonistas & inhibidores , Nitrilos/farmacología , Nitritos/metabolismo , Sulfonas/farmacología , Translocación Genética/efectos de los fármacosRESUMEN
Dehydroepiandrosterone, an adrenal hormone derived from cholesterol, can be metabolized to estrogens (estradiol) and androgens (testosterone). In this study, we evaluated whether the antiproliferative effect induced by dehydroepiandrosterone in MCF-7 cells (an estrogen-dependent breast cancer cell line) is direct, or indirect, through its conversion to estradiol or testosterone. Although dehydroepiandrosterone had an antiproliferative effect at supraphysiologic concentrations, when it was used at physiologic concentrations, it increased the proliferation of MCF-7 cells. 17Beta-estradiol induced an increase in MCF-7 cell proliferation at physiologic concentrations, whereas testosterone had a weak inhibitory effect at 100 microM. Dehydroepiandrosterone sulfate (its inactive sulfate ester) had no effect upon the cell cycle. Dehydroepiandrosterone-induced antiproliferative and proliferative effects were not blocked by inhibitors of androgen or estrogen receptors, thus indicating that its effect is secondary to a direct interaction with a "putative" receptor rather than a conversion into steroid hormones. These results suggest that dehydroepiandrosterone could be used at supraphysiologic concentrations in the treatment of breast cancer.