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1.
Toxicol Appl Pharmacol ; 487: 116955, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38710373

RESUMO

Lung cancer is one of the most aggressive malignancies with a high mortality rate. In large cities, particulate matter (PM) is a common air pollutant. High PM levels with aerodynamic size ≤2.5 µm (PM2.5) associates with lung cancer incidence and mortality. In this work, we explored PM2.5 effects on the behavior of lung cancer cells. To this, we chronically exposed A549 cells to increasing PM2.5 concentrations collected in México City, then evaluating cell proliferation, chemoresponse, migration, invasion, spheroid formation, and P-glycoprotein and N-cadherin expression. Chronic PM2.5 exposure from 1 µg/cm2 stimulated A549 cell proliferation, migration, and chemoresistance and upregulated P-glycoprotein and N-cadherin expression. PM2.5 also induced larger multicellular tumor spheroids (MCTS) and less disintegration compared with control cells. Therefore, these results indicate lung cancer patients exposed to airborne PM2.5 as urban pollutant could develop more aggressive tumor phenotypes, with increased cell proliferation, migration, and chemoresistance.


Assuntos
Poluentes Atmosféricos , Movimento Celular , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos , Neoplasias Pulmonares , Material Particulado , Humanos , Material Particulado/toxicidade , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/metabolismo , Células A549 , Proliferação de Células/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Poluentes Atmosféricos/toxicidade , Fenótipo , Caderinas/metabolismo , Tamanho da Partícula , México , Esferoides Celulares/efeitos dos fármacos , Invasividade Neoplásica , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Antígenos CD/metabolismo
2.
Int J Mol Sci ; 25(11)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38892068

RESUMO

Food-grade titanium dioxide (E171) and zinc oxide nanoparticles (ZnO NPs) are common food additives for human consumption. We examined multi-organ toxicity of both compounds on Wistar rats orally exposed for 90 days. Rats were divided into three groups: (1) control (saline solution), (2) E171-exposed, and (3) ZnO NPs-exposed. Histological examination was performed with hematoxylin-eosin (HE) staining and transmission electron microscopy (TEM). Ceramide (Cer), 3-nitrotyrosine (NT), and lysosome-associated membrane protein 2 (LAMP-2) were detected by immunofluorescence. Relevant histological changes were observed: disorganization, inflammatory cell infiltration, and mitochondrial damage. Increased levels of Cer, NT, and LAMP-2 were observed in the liver, kidney, and brain of E171- and ZnO NPs-exposed rats, and in rat hearts exposed to ZnO NPs. E171 up-regulated Cer and NT levels in the aorta and heart, while ZnO NPs up-regulated them in the aorta. Both NPs increased LAMP-2 expression in the intestine. In conclusion, chronic oral exposure to metallic NPs causes multi-organ injury, reflecting how these food additives pose a threat to human health. Our results suggest how complex interplay between ROS, Cer, LAMP-2, and NT may modulate organ function during NP damage.


Assuntos
Ceramidas , Nanopartículas Metálicas , Ratos Wistar , Titânio , Óxido de Zinco , Animais , Óxido de Zinco/toxicidade , Titânio/toxicidade , Titânio/efeitos adversos , Ratos , Ceramidas/metabolismo , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Masculino , Administração Oral , Proteína 2 de Membrana Associada ao Lisossomo/metabolismo , Tirosina/análogos & derivados , Tirosina/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia
3.
Part Fibre Toxicol ; 20(1): 43, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37978398

RESUMO

BACKGROUND: Metallic nanoparticles (NPs) are widely used as food additives for human consumption. NPs reach the bloodstream given their small size, getting in contact with all body organs and cells. NPs have adverse effects on the respiratory and intestinal tract; however, few studies have focused on the toxic consequences of orally ingested metallic NPs on the cardiovascular system. Here, the effects of two food-grade additives on the cardiovascular system were analyzed. METHODS: Titanium dioxide labeled as E171 and zinc oxide (ZnO) NPs were orally administered to Wistar rats using an esophageal cannula at 10 mg/kg bw every other day for 90 days. We evaluated cardiac cell morphology and death, expression of apoptotic and autophagic proteins in cardiac mitochondria, mitochondrial dysfunction, and concentration of metals on cardiac tissue. RESULTS: Heart histology showed important morphological changes such as presence of cellular infiltrates, collagen deposition and mitochondrial alterations in hearts from rats exposed to E171 and ZnO NPs. Intracellular Cyt-C levels dropped, while TUNEL positive cells increased. No significant changes in the expression of inflammatory cytokines were detected. Both NPs altered mitochondrial function indicating cardiac dysfunction, which was associated with an elevated concentration of calcium. ZnO NPs induced expression of caspases 3 and 9 and two autophagic proteins, LC3B and beclin-1, and had the strongest effect compared to E171. CONCLUSIONS: E171 and ZnO NPs induce adverse cardiovascular effects in rats after 90 days of exposure, thus food intake containing these additives, should be taken into consideration, since they translocate into the bloodstream and cause cardiovascular damage.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Óxido de Zinco , Ratos , Humanos , Animais , Óxido de Zinco/toxicidade , Ratos Wistar , Nanopartículas/toxicidade , Coração , Nanopartículas Metálicas/toxicidade , Titânio/toxicidade , Aditivos Alimentares/toxicidade
4.
Int J Mol Sci ; 24(23)2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-38068956

RESUMO

The objective of this study was to investigate whether the activity of enzymes involved in sphingolipid catabolism could be biomarkers to predict early renal damage in streptozotocin (STZ)-induced diabetic rats and Angiotensin II (Ang II)-induced hypertension rats. Diabetic and hypertensive rats had no changes in plasma creatinine concentration. However, transmission electron microscopy (TEM) analysis showed slight ultrastructural changes in the glomeruli and tubular epithelial cells from diabetic and hypertensive rats. Our results show that the acid sphingomyelinase (aSMase) and neutral sphingomyelinase (nSMase) activity increased in the urine of diabetic rats and decreased in hypertensive rats. Only neutral ceramidase (nCDase) activity increased in the urine of diabetic rats. Furthermore, the immunofluorescence demonstrated positive staining for the nSMase, nCDase, and sphingosine kinase (SphK1) in glomerular mesangial cells, proximal tubule, ascending thin limb of the loop of Henle, thick ascending limb of Henle's loop, and principal cells of the collecting duct in the kidney. In conclusion, our results suggest that aSMase and nCDase activity in urine could be a novel predictor of early slight ultrastructural changes in the nephron, aSMase and nCDase as glomerular injury biomarkers, and nSMase as a tubular injury biomarker in diabetic and hypertensive rats.


Assuntos
Diabetes Mellitus Experimental , Hipertensão , Ratos , Animais , Esfingomielina Fosfodiesterase/metabolismo , Diabetes Mellitus Experimental/metabolismo , Rim/metabolismo , Néfrons/metabolismo , Esfingolipídeos
5.
Int J Mol Sci ; 23(21)2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36361726

RESUMO

Zinc oxide nanoparticles (ZnO NPs) are widely used in the cosmetic industry. They are nano-optical and nano-electrical devices, and their antimicrobial properties are applied in food packaging and medicine. ZnO NPs penetrate the body through inhalation, oral, and dermal exposure and spread through circulation to various systems and organs. Since the cardiovascular system is one of the most vulnerable systems, in this work, we studied ZnO NPs toxicity in H9c2 rat cardiomyoblasts. Cardiac cells were exposed to different concentrations of ZnO NPs, and then the morphology, proliferation, viability, mitochondrial membrane potential (ΔΨm), redox state, and protein expression were measured. Transmission electron microscopy (TEM) and hematoxylin-eosin (HE) staining showed strong morphological damage. ZnO NPs were not observed inside cells, suggesting that Zn2+ ions were internalized, causing the damage. ZnO NPs strongly inhibited cell proliferation and MTT reduction at 10 and 20 µg/cm2 after 72 h of treatment. ZnO NPs at 20 µg/cm2 elevated DCF fluorescence, indicating alterations in the cellular redox state associated with changes in ΔΨm and cell death. ZnO NPs also reduced the intracellular expression of troponin I and atrial natriuretic peptide. ZnO NPs are toxic for cardiac cells; therefore, consumption of products containing them could cause heart damage and the development of cardiovascular diseases.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Óxido de Zinco , Ratos , Animais , Óxido de Zinco/química , Nanopartículas/toxicidade , Nanopartículas/química , Microscopia Eletrônica de Transmissão , Oxirredução , Íons , Nanopartículas Metálicas/toxicidade , Nanopartículas Metálicas/química
6.
Environ Res ; 198: 111242, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33933488

RESUMO

BACKGROUND: Epidemiological evidence associates chronic exposure to particulate matter (PM) with respiratory damage and lung cancer. Inhaled PM may induce systemic effects including inflammation and metastasis. This study evaluated whether PM induces expression of adhesion molecules in lung cancer cells promoting interaction with monocytes. METHODS: The expression of early and late adhesion molecules and their receptors was evaluated in A549 (human lung adenocarcinoma) cells using a wide range of concentrations of PM2.5 and PM10. Then we evaluated cellular adhesion between A549 cells and U937 (human monocytes) cells after PM exposure. RESULTS: We found higher expression of both early and late adhesion molecules and their ligands in lung adenocarcinoma cells exposed to PM2.5 and PM10 particles present in the air pollution at Mexico City from 0.03 µg/cm2 with a statistically significant difference (p ≤ 0.05). PM10 had stronger effect than PM2.5. Both PM also stimulated cellular adhesion between tumor cells and monocytes. CONCLUSIONS: This study reveals a comprehensive expression profile of adhesion molecules and their ligands upregulated by PM2.5 and PM10 in A549 cells. Additionally these particles induced cellular adhesion of lung cancer cells to monocytes. This highlights possible implications of PM in two cancer hallmarks i.e. inflammation and metastasis, underlying the high cancer mortality associated with air pollution.


Assuntos
Adenocarcinoma de Pulmão , Poluentes Atmosféricos , Poluição do Ar , Neoplasias Pulmonares , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Poluição do Ar/análise , Linhagem Celular , Cidades , Humanos , México , Material Particulado/análise , Material Particulado/toxicidade
7.
Toxicol Appl Pharmacol ; 370: 65-77, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30878505

RESUMO

The resveratrol (RSV) efficacy to affect the proliferation of several cancer cell lines was initially examined. RSV showed higher potency to decrease growth of metastatic HeLa and MDA-MB-231 (IC50 = 200-250 µM) cells than of low metastatic MCF-7, SiHa and A549 (IC50 = 400-500 µM) and non-cancer HUVEC and 3T3 (IC50≥600 µM) cells after 48 h exposure. In order to elucidate the biochemical mechanisms underlying RSV anti-cancer effects, the energy metabolic pathways and the oxidative stress metabolism were analyzed in HeLa cells as metastatic-type cell model. RSV (200 µM/48 h) significantly decreased both glycolysis and oxidative phosphorylation (OxPhos) protein contents (30-90%) and fluxes (40-70%) vs. non-treated cells. RSV (100 µM/1-5 min) also decreased at a greater extent OxPhos flux (net ADP-stimulated respiration) of isolated tumor mitochondria (> 50%) than of non-tumor mitochondria (< 50%), particularly with succinate as oxidizable substrate. In addition, RSV promoted an excessive cellular ROS (2-3 times) production corresponding with a significant decrement in the SOD activity (but not in its content) and GSH levels; whereas the catalase, glutahione reductase, glutathione peroxidase and glutathione-S-transferase activities (but not their contents) remained unchanged. RSV (200 µM/48 h) also induced cellular death although not by apoptosis but rather by promoting a strong mitophagy activation (65%). In conclusion, RSV impaired OxPhos by inducing mitophagy and ROS over-production, which in turn halted metastatic HeLa cancer cell growth.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias/patologia , Fosforilação Oxidativa/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Resveratrol/farmacologia , Células 3T3 , Animais , Linhagem Celular Tumoral , Células HeLa , Células Endoteliais da Veia Umbilical Humana , Humanos , Células MCF-7 , Camundongos , Mitofagia/efeitos dos fármacos , Metástase Neoplásica/prevenção & controle , Compostos Fitoquímicos/farmacologia
8.
Chem Res Toxicol ; 32(4): 578-588, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30730135

RESUMO

Titanium dioxide nanoparticles (TiO2 NPs) are widely used for industrial and commercial applications. Once inside the body, they translocate into the bloodstream and reach different areas of the cardiovascular system including the heart, increasing the risk of developing cardiovascular diseases; consequently, the investigation of their interaction with cardiac cells is required. We previously showed that TiO2 NPs are internalized by H9c2 rat cardiomyoblasts, and here, we examined the molecular mechanisms underlying this process. TiO2 NPs internalization was evaluated by transmission electron microscopy, time-lapse microscopy, and flow cytometry. Changes in the actin cytoskeleton were studied by phalloidin staining. Endocytic uptake mechanisms for nanoparticles were probed with chemical inhibitors, whereas clathrin and dynamin expression was measured by Western blot. Cellular uptake of TiO2 NPs occurred early after 30 min exposure, and large aggregates were observed after 1 h. Actin cytoskeleton reorganization included cell elongation plus lower density and stability of actin fibers. Cytochalasin-D inhibited TiO2 NPs uptake, indicating actin-mediated internalization. Dynamin and clathrin levels increased early after TiO2 NPs exposure, and their inhibition reduced nanoparticle uptake. Therefore, TiO2 NPs internalization by H9c2 rat cardiomyoblasts involves actin cytoskeleton reorganization and clathrin/dynamin-mediated endocytosis.


Assuntos
Actinas/metabolismo , Clatrina/metabolismo , Dinaminas/metabolismo , Miócitos Cardíacos/metabolismo , Nanopartículas/química , Titânio/metabolismo , Actinas/química , Animais , Células Cultivadas , Clatrina/química , Dinaminas/química , Endocitose , Ratos , Titânio/química
9.
Int J Mol Sci ; 20(13)2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31252520

RESUMO

The epithelial sodium channel (ENaC) has a key role in modulating endothelial cell stiffness and this in turn regulates nitric oxide (NO) synthesis. The physiological relevance of endothelial ENaC in pathological conditions where reduced NO bioavailability plays an essential role remains largely unexplored. Renal ischemia/reperfusion (IR) injury is characterized by vasoconstriction and sustained decrease in renal perfusion that is partially explained by a reduction in NO bioavailability. Therefore, we aimed to explore if an endothelial ENaC deficiency has an impact on the severity of renal injury induced by IR. Male mice with a specific endothelial sodium channel α (αENaC) subunit gene inactivation in the endothelium (endo-αENaCKO) and control littermates were subjected to bilateral renal ischemia of 22 min and were studied after 24 h of reperfusion. In control littermates, renal ischemia induced an increase in plasma creatinine and urea, augmented the kidney injury molecule-1 (Kim-1) and neutrophil gelatinase associated lipocalin-2 (NGAL) mRNA levels, and produced severe tubular injury. The absence of endothelial αENaC expression prevented renal tubular injury and renal dysfunction. Moreover, endo-αENaCKO mice recovered faster from renal hypoxia after the ischemia episode as compared to littermates. In human endothelial cells, pharmacological ENaC inhibition promoted endothelial nitric oxide synthase (eNOS) coupling and activation. Altogether, these data suggest an important role for endothelial αENaC in kidney IR injury through improving eNOS activation and kidney perfusion, thus, preventing ischemic injury.


Assuntos
Canais Epiteliais de Sódio/genética , Traumatismo por Reperfusão/metabolismo , Animais , Células Cultivadas , Canais Epiteliais de Sódio/deficiência , Receptor Celular 1 do Vírus da Hepatite A/genética , Receptor Celular 1 do Vírus da Hepatite A/metabolismo , Humanos , Rim/irrigação sanguínea , Rim/metabolismo , Rim/patologia , Lipocalina-2/genética , Lipocalina-2/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo III/metabolismo , Traumatismo por Reperfusão/genética
10.
Environ Res ; 167: 283-291, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30077136

RESUMO

Exposure to urban particulate matter (PM) is correlated with increases in the emergence of health services due to adverse events and deaths and is mainly related to cardiorespiratory complications. The translocation of particles from the lung into circulation has been proposed as a factor that may trigger systemic effects. Monocytes may be exposed to PM, and if the monocytes are activated, then they are likely to adhere to endothelial cells in a distant organ due to the expression of receptors for adhesion molecules. In the present study, we evaluated the expression of receptors for adhesion molecules (sLex, PSGL-1, LFA-1, VLA-4 and αVß3) in monocytes (U937 cells) exposed for 3 or 18 h to PM10 (0.001, 0.003, 0.010, 0.030, 0.300, 3 or 30 µg/mL). Exposed cells were co-cultured with human endothelial cells that were naive or previously exposed to the same particles. When U937 cells were exposed to PM10, similar levels of expression for early and late receptors for adhesion molecules were observed from 30 ng/mL as those induced by TNF-α. Cells exposed to particles at concentrations above 30 ng/mL were more adhesive to naive or exposed human endothelial cells. Taken together, our results suggest that it is plausible that activated monocytes may play a role in systemic effects induced by PM10 due to the size distribution of the particles and the concentrations required to trigger the expression of receptors for adhesion molecules in monocytes.


Assuntos
Moléculas de Adesão Celular/metabolismo , Monócitos/metabolismo , Material Particulado/farmacologia , Células Endoteliais/metabolismo , Humanos , Células U937
11.
Environ Res ; 161: 439-445, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29216490

RESUMO

Endocrine disrupting chemicals (EDCs) from the environment are associated with reproductive abnormalities (i.e. decreased sperm concentration; increased endometriosis) and alterations of the cardiovascular system (i.e. increased blood pressure and risk of coronary disease). Some phthalates esters have been identified as EDCs, for which inhalation is considered as one of the routes of exposure. However, only little is known regarding inhalational exposure to EDCs via urban airborne particles. In the present study, we report the monthly concentration of 8 phthalate esters measured in PM10 and PM2.5 collected and recovered during 7 months in a highly populated area of Mexico City. Using the levels of PM10 and PM2.5 reported by the automatized network of environmental monitoring of Mexico City for the sampling site, we estimated exposure levels for people of different ages and gender. Two endocrine disrupting compounds, the phthalate esters DEHP and DnBP, were found on the particles in higher concentrations during the warmer months of the year. The highest concentration was reported for DEHP (229.7µg/g of particles) in PM2.5 collected in May 2013. After calculations of the DEHP concentration in the atmosphere, and using the respiratory flow rate, we determined males were potentially exposed to larger quantities of DEHP, reaching up to 18ng/8h in April 2013. Despite the concentrations of phthalates seem to be rather small, a comprehensive characterization of its presence is necessary in order to evaluate the overall exposure to these compounds, providing a clear view of exposure on children, adolescents and pregnant women.


Assuntos
Poluentes Atmosféricos/análise , Dietilexilftalato , Exposição por Inalação , Pulmão , Ácidos Ftálicos , Adolescente , Criança , Cidades , Exposição Ambiental , Ésteres , Feminino , Humanos , Masculino , México , Material Particulado , Ácidos Ftálicos/análise , Gravidez
12.
Molecules ; 23(8)2018 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-30082584

RESUMO

Titanium dioxide nanoparticles (TiO2 NPs) are widely used in industry and daily life. TiO2 NPs can penetrate into the body, translocate from the lungs into the circulation and come into contact with cardiac cells. In this work, we evaluated the toxicity of TiO2 NPs on H9c2 rat cardiomyoblasts. Internalization of TiO2 NPs and their effect on cell proliferation, viability, oxidative stress and cell death were assessed, as well as cell cycle alterations. Cellular uptake of TiO2 NPs reduced metabolic activity and cell proliferation and increased oxidative stress by 19-fold measured as H2DCFDA oxidation. TiO2 NPs disrupted the plasmatic membrane integrity and decreased the mitochondrial membrane potential. These cytotoxic effects were related with changes in the distribution of cell cycle phases resulting in necrotic death and autophagy. These findings suggest that TiO2 NPs exposure represents a potential health risk, particularly in the development of cardiovascular diseases via oxidative stress and cell death.


Assuntos
Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Nanopartículas/química , Nanopartículas/toxicidade , Titânio/química , Titânio/toxicidade , Animais , Autofagia/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ratos
13.
Toxicol Appl Pharmacol ; 333: 26-34, 2017 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-28803991

RESUMO

Breast cancer is one of the most common neoplasias and the leading cause of cancer death in women worldwide. Its high mortality rate is linked to a great metastatic capacity associated with the epithelial-mesenchymal transition (EMT). During this process, a decrease in epithelial proteins expression and an increase of mesenchymal proteins are observed. On the other hand, it has been shown that dehydroepiandrosterone (DHEA), the most abundant steroid in human plasma, inhibits migration of breast cancer cells; however, the underlying mechanisms have not been elucidated. In this study, the in vitro effect of DHEA on the expression pattern of some EMT-related proteins, such as E-cadherin (epithelial), N-cadherin, vimentin and Snail (mesenchymal) was measured by Western blot and immunofluorescence in MDA-MB-231 breast cancer cells with invasive, metastatic and mesenchymal phenotype. Also, the in vivo effect of DHEA on xenograft tumor growth in nude mice (nu-/nu-) and on expression of the same epithelial and mesenchymal proteins in generated tumors was evaluated. We found that DHEA increased expression of E-cadherin and decreased N-cadherin, vimentin and Snail expression both in MD-MB-231 cells and in the formed tumors, possibly by DHEA-induced reversion of mesenchymal phenotype. These results were correlated with a tumor size reduction in mouse xenografts following DHEA administration either a week earlier or concurrent with breast cancer cells inoculation. In conclusion, DHEA could be useful in the treatment of breast cancer with mesenchymal phenotype.


Assuntos
Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Desidroepiandrosterona/farmacologia , Desidroepiandrosterona/uso terapêutico , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Caderinas/metabolismo , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Feminino , Humanos , Camundongos Nus , Fatores de Transcrição da Família Snail/metabolismo , Carga Tumoral/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Vimentina/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Mol Membr Biol ; 33(1-2): 29-37, 2016 03.
Artigo em Inglês | MEDLINE | ID: mdl-27690154

RESUMO

Metastases, responsible for most of the solid tumor associated deaths, require angiogenesis and changes in endothelial cells. In this work, the effect of the secretomes of three breast tumor cell lines (MCF-7, MDA-MB-231 and ZR-75-30) on human umbilical vein endothelial cells (HUVEC) morphology was investigated. HUVEC treated with secretomes from breast cells were analyzed by confocal and time-lapse microscopy. Secretomes from ZR-75-30 and MDA-MB-231 cells modify the morphology and adhesion of HUVEC. These changes may provoke the loss of endothelial monolayer integrity. In consequence, tumor cells could have an increased access to circulation, which would then enhance metastasis.


Assuntos
Meios de Cultura/farmacologia , Células Endoteliais/efeitos dos fármacos , Proteínas/metabolismo , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Técnicas de Cocultura , Células Endoteliais/citologia , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Células MCF-7
15.
Part Fibre Toxicol ; 13(1): 36, 2016 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-27338562

RESUMO

BACKGROUND: There is growing evidence that exposure to titanium dioxide nanoparticles (TiO2 NPs) could be harmful. Previously, we have shown that TiO2 NPs induces endothelial cell dysfunction and damage in glial cells. Considering that inhaled particles can induce systemic effects and the evidence that nanoparticles may translocate out of the lungs, we evaluated whether different types of TiO2 NPs can induce the expression of receptors for adhesion molecules on monocytes (U937 cell line). We evaluated the role of reactive oxygen spices (ROS) on these effects. METHODS: The expression of receptors for early (sLe(x) and PSGL-1) and late (LFA-1, VLA-4 and αVß3) adhesion molecules was evaluated in U937 cells on a time course (3-24 h) using a wide range of concentrations (0.001-100 µg/mL) of three types of TiO2 NPs (<25 nm anatase, 50 nm anatase-rutile or < 100 nm anatase). Cells exposed to TNFα were considered positive controls, and unexposed cells, negative controls. In some experiments we added 10 µmolar of N-acetylcysteine (NAC) to evaluate the role of ROS. RESULTS: All tested particles, starting at a concentration of 0.03 µg/mL, induced the expression of receptors for early and late adhesion molecules. The largest increases were induced by the different molecules after 3 h of exposure for sLe(x) and PSGL-1 (up to 3-fold of the positive controls) and after 18 h of exposure for LFA-1, VLA-4 and αVß3 (up to 2.5-fold of the positive controls). Oxidative stress was observed as early as 10 min after exposure, but the maximum peak was found after 4 h of exposure. Adhesion of exposed or unexposed monocytes to unexposed or exposed endothelial cells was tested, and we observed that monocytes cells adhere in similar amounts to endothelial cells if one of the two cell types, or both were exposed. When NAC was added, the expression of the receptors was inhibited. CONCLUSIONS: These results show that small concentrations of particles may activate monocytes that attach to endothelial cells. These results suggest that distal effects can be induced by small amounts of particles that may translocate from the lungs. ROS play a central role in the induction of the expression of these receptors.


Assuntos
Moléculas de Adesão Celular/metabolismo , Nanopartículas Metálicas/toxicidade , Monócitos/metabolismo , Titânio/química , Humanos , Nanopartículas Metálicas/química , Monócitos/citologia , Células U937
16.
Molecules ; 20(12): 21125-37, 2015 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-26633316

RESUMO

Argentatin B has been shown to inhibit the growth of colon HCT-15, and prostate PC-3 cancer cells. However, the mechanism by which argentatin B inhibits cell proliferation is still unknown. We aimed to investigate the mechanism by which argentatin B inhibits cell proliferation. The cell cycle was studied by flow cytometry. Apoptosis was evaluated by Annexin-V-Fluos, and Hoechst 33342 dye staining. Cell senescence was evaluated by proliferation tests, and staining for SA-ß-galactosidase. Senescence-related proteins (PCNA, p21, and p27) were analyzed by Western blotting. Potential toxicity of argentatin B was evaluated in CD-1 mice. Its effect on tumor growth was tested in a HCT-15 and PC-3 xenograft model. Argentatin B induced an increment of cells in sub G1, but did not produce apoptosis. Proliferation of both cell lines was inhibited by argentatin B. Forty-three percent HCT-15, and 66% PC-3 cells showed positive SA-ß-galactosidase staining. The expression of PCNA was decreased, p21 expression was increased in both cell lines, but p27 expression increased only in PC-3 cells after treatment. Administration of argentatin B to healthy mice did not produce treatment-associated pathologies. However, it restricted the growth of HCT-15 and PC-3 tumors. These results indicate that treatment with argentatin B induces cell senescence.


Assuntos
Proliferação de Células/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Neoplasias do Colo/patologia , Neoplasias da Próstata/patologia , Triterpenos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Ciclo Celular/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Citometria de Fluxo , Humanos , Masculino , Camundongos , Camundongos Nus , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
17.
J Nat Prod ; 77(11): 2404-9, 2014 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-25402632

RESUMO

The new 2-acetyl-8-methoxynaphthol (1) and five new "dimeric" napthopyranones, karwinaphthopyranones A1 and A2 (2 and 3) and karwinaphthopyranones B1-B3 (4-6), possessing a methoxy group at C-5', were isolated together with four other known compounds from the dried fruits of Karwinskia parvifolia. The structures of compounds 2-6 were determined by spectroscopic data interpretation. Cell culture assays showed that some of these compounds possess antiproliferative activities in representative human cancer cell lines, with half-maximal growth inhibitory concentrations in the micromolar range.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Karwinskia/química , Naftóis/isolamento & purificação , Naftóis/farmacologia , Pironas/isolamento & purificação , Pironas/farmacologia , Antineoplásicos Fitogênicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Frutas/química , Células HCT116 , Células Hep G2 , Humanos , Estrutura Molecular , Naftóis/química , Pironas/química
18.
ScientificWorldJournal ; 2014: 187071, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24578622

RESUMO

BACKGROUND: CDP-choline is a key intermediate in the biosynthesis of phosphatidylcholine, which is an essential component of cellular membranes, and a cell signalling mediator. CDP-choline has been used for the treatment of cerebral ischaemia, showing beneficial effects. However, its potential benefit for the treatment of myocardial ischaemia has not been explored yet. AIM: In the present work, we aimed to evaluate the potential use of CDP-choline as a cardioprotector in an in vitro model of ischaemia/reperfusion injury. METHODS: Neonatal rat cardiac myocytes were isolated and subjected to hypoxia/reperfusion using the coverslip hypoxia model. To evaluate the effect of CDP-choline on oxidative stress-induced reperfusion injury, the cells were incubated with H2O2 during reperfusion. The effect of CDP-choline pre- and postconditioning was evaluated using the cell viability MTT assay, and the proportion of apoptotic and necrotic cells was analyzed using the Annexin V determination by flow cytometry. RESULTS: Pre- and postconditioning with 50 mg/mL of CDP-choline induced a significant reduction of cells undergoing apoptosis after hypoxia/reperfusion. Preconditioning with CDP-choline attenuated postreperfusion cell death induced by oxidative stress. CONCLUSION: CDP-choline administration reduces cell apoptosis induced by oxidative stress after hypoxia/reperfusion of cardiac myocytes. Thus, it has a potential as cardioprotector in ischaemia/reperfusion-injured cardiomyocytes.


Assuntos
Apoptose/efeitos dos fármacos , Cardiotônicos/farmacologia , Citidina Difosfato Colina/farmacologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miócitos Cardíacos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Hipóxia Celular/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Masculino , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miócitos Cardíacos/patologia , Oxidantes/farmacologia , Ratos , Ratos Wistar
19.
Nanotoxicology ; 18(2): 122-133, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38436290

RESUMO

Food-grade titanium dioxide (E171) and zinc oxide nanoparticles (ZnO NPs) are found in diverse products for human use. E171 is used as whitening agent in food and cosmetics, and ZnO NPs in food packaging. Their potential multi-organ toxicity has raised concerns on their safety. Since mitochondrial dysfunction is a key aspect of cardio-pathologies, here, we evaluate the effect of chronic exposure to E171 and ZnO NPs in rats on cardiac mitochondria. Changes in cardiac electrophysiology and body weight were measured. E171 reduced body weight more than 10% after 5 weeks. Both E171 and ZnO NPs increased systolic blood pressure (SBP) from 110-120 to 120-140 mmHg after 45 days of treatment. Both NPs altered the mitochondrial permeability transition pore (mPTP), reducing calcium requirement for permeability by 60% and 93% in E171- and ZnO NPs-exposed rats, respectively. Treatments also affected conformational state of adenine nucleotide translocase (ANT). E171 reduced the binding of EMA to Cys 159 in 30% and ZnO NPs in 57%. Mitochondrial aconitase activity was reduced by roughly 50% with both NPs, indicating oxidative stress. Transmission electron microscopy (TEM) revealed changes in mitochondrial morphology including sarcomere discontinuity, edema, and hypertrophy in rats exposed to both NPs. In conclusion, chronic oral exposure to NPs induces functional and morphological damage in cardiac mitochondria, with ZnO NPs being more toxic than E171, possibly due to their dissociation in free Zn2+ ion form. Therefore, chronic intake of these food additives could increase risk of cardiovascular disease.


Assuntos
Mitocôndrias Cardíacas , Titânio , Óxido de Zinco , Animais , Titânio/toxicidade , Óxido de Zinco/toxicidade , Óxido de Zinco/química , Mitocôndrias Cardíacas/efeitos dos fármacos , Mitocôndrias Cardíacas/metabolismo , Masculino , Ratos , Administração Oral , Permeabilidade/efeitos dos fármacos , Poro de Transição de Permeabilidade Mitocondrial/metabolismo , Nanopartículas Metálicas/toxicidade , Nanopartículas/toxicidade , Nanopartículas/química , Ratos Sprague-Dawley , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos
20.
Growth Factors ; 31(4): 123-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23750889

RESUMO

The aim of this study was to investigate the associations between insulin-like growth factor I (IGF-I) with vascular endothelial growth factor (VEGF) and its soluble receptor 1 (sFlt-1) in umbilical serum and to study the effects of IGF-I upon sFlt-1 synthesis in human umbilical vein endothelial cells (HUVEC) in normotensive (NT) and preeclamptic (PE) pregnancies. As compared with the NT group, umbilical serum IGF-I and VEGF levels were lower in the PE group, while sFlt-1 concentrations were higher. Levels of sFlt-1 correlated with IGF-I in the NT group and with VEGF in the PE group. Basal concentration of sFlt-1 in HUVEC culture media was higher in the PE group. IGF-I stimulated sFlt-1 synthesis only in the NT group. In summary, umbilical serum sFlt-1 is associated with IGF-I in normotensive pregnancy and with VEGF in preeclampsia. IGF-I stimulates sFlt-1 synthesis in endothelial cells in normotensive but not in PE pregnancies.


Assuntos
Fator de Crescimento Insulin-Like I/metabolismo , Pré-Eclâmpsia/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Adulto , Estudos de Casos e Controles , Feminino , Sangue Fetal/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Recém-Nascido , Pré-Eclâmpsia/sangue , Gravidez
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