1 |
IN VITRO LUNG EPITHELIAL CELL TRANSPORT AND ANTI-INFLAMMATORY ACTIVITY FOR LIPOSOMAL CIPROFLOXACINDarweesh, Ruba 01 January 2013 (has links)
Liposomal ciprofloxacin (Lipo-CPFX) is being developed for inhalation, with a goal of sustaining the therapeutic activity, compared to unformulated ciprofloxacin (CPFX). However, the kinetics and mechanism of its sustained local lung retention and pharmacological activity are yet to be fully characterized. This project hypothesized that Lipo-CPFX enables slower and sustained lung epithelial transport and uptake, compared to CPFX, thereby producing prolonged local pharmacological actions. The human bronchial epithelial Calu-3 cells were used as monolayers to characterize the kinetics and mechanism of transport and/or uptake, and to assess the effects of such slow kinetics for Lipo-CPFX on its inhibition against lipopolysaccharide (LPS)-induced proinflammatory IL-8 release. The transport fluxes for Lipo-CPFX across the highly restricted Calu-3 cell monolayers was transepithelial electrical resistance-independent, which suggested predominant transcellular transport. Compared to CPFX, Lipo-CPFX showed 6-18 times slower transport, while the flux was increased with increasing concentration proportionally without saturation. Its unaltered transport by cellular energy depletion, transport inhibition by a reduced temperature (4 oC) and endocytosis/lipid fusion inhibitors, filipin and LysoPC, and increased transport by excess empty liposomes collectively suggested cell energy-independent, lipid bilayer fusion mechanisms for the Lipo-CPFX transport across the Calu-3 cells. Likewise, Lipo-CPFX showed 2-4 fold lower cellular uptake than CPFX, proportional to concentration. Lipo-CPFX exhibited significant inhibitory activities at ≥ 0.01 mg/mL on LPS-induced IL-8 release from the Calu-3 cells, which was equipotent to CPFX. Upon 24 h pre-incubation, Lipo-CPFX caused 36.9 and 47.5 % inhibition at 0.01 and 0.05 mg/mL, respectively, while CPFX failed to do so. However, the effect was negated upon repeated wash of the mucosal cell surface, speculating the importance of cell membrane-associated drug/formulation on the inhibitory activities for Lipo-CPFX. Upon 24 h transport, Lipo-CPFX retained 79.0 % of the 4 µg dose on the mucosal cell surface, which was 1.9-times greater than 40.7 % for CPFX. As a result, when LPS was added at 24 h of the transport, Lipo-CPFX was still capable of causing 60.1 % inhibition, as its sustained local anti-inflammatory activity; CPFX however also exhibited equipotent inhibition, by virtue of comparable cellular drug uptake/transport.
|
2 |
Investigating Streptococcus pneumoniae and Adenovirus Co-infections of Lung Epithelial CellsCalabro, Mark Nicholas January 2021 (has links)
No description available.
|
3 |
Propriétés biochimiques, enzymatiques et physiologiques de la Human Airway Trypsin-like protease (HAT)Maurice, Kelly January 2010 (has links)
La fibrose kystique (FK) est caractérisée par une inflammation pulmonaire chronique. Cette dernière est définie entre autres par une augmentation importante de la production de mucus. Celui-ci s'accumule dans les bronches empêchant ainsi l'éventuel passage de l'air. De plus, le mucus forme une barrière protectrice pour les bactéries qui va causer l'inflammation des poumons. La protéase human airway trypsin-like (HAT) a été retrouvée dans les expectorations de patients atteints d'asthme et bronchite chronique, pathologies similaires à la FK. Elle semble jouer un rôle dans l'inflammation car elle augmente entre autres la production de MUC5AC, protéine composant majoritairement le mucus. Le but de cette étude était de synthétiser la HAT dans une conformation active dans un système eucaryote pour étudier ses propriétés biochimiques, enzymatiques ainsi que son potentiel pro-inflammatoire dans la lignée cellulaire pulmonaire Calu-3. L'ADNc codant pour la partie soluble de la HAT a été inséré dans le vecteur pMT-BiP V5-His. Cet ADN recombinant fut ensuite transfecté dans les cellules de Drosophile Schneider 2 (S2). La HAT recombinante a par la suite été purifiée et son activité protéolytique testée avec un substrat fluorogénique. Ses propriétés biochimiques et enzymatiques ont été étudiées ainsi que son effet sur la production d'IL-8 et sa détection dans les expectorations de patients. La HAT purifiée était «enzymatiquement» pure, donc l'effet protéolytique observé avec le substrat fluorogénique est dû à la protéase. Les analyses de ses propriétés biochimiques montrent que l'activité protéolytique de la HAT est inhibée par un pH acide (<6.5), certains inhibiteurs synthétiques (l'aprotinine, la leupeptine et le PEFABLOC) et endogène (i.e: alpha-2 anti-plasmine (a2-AP)) de protéases à sérine. D'un autre côté, les essais enzymatiques révèlent que la HAT a une préférence pour les substrats ayant une arginine en P4, P3 et Pl plutôt que ceux ayant un glutamate en P4, P2 et P1'. Finalement, l'étude sur l'implication physiologique de l'enzyme démontre que la protéase ne semble pas avoir d'effet ou au plus peu d'effet sur la production d' IL-8. [Symboles non conformes]
|
4 |
AVALIAÇÃO DA CITOTOXICIDADE DA FASE VAPOR DO ÓLEO ESSENCIAL DE Jasminum officinale EM CALU-3 (ADENOCARCINOMA DE PULMÃO) E 3T3 (FIBROBLASTOS)Kosmo, Daniele de Fátima 07 July 2017 (has links)
Submitted by Angela Maria de Oliveira (amolivei@uepg.br) on 2018-07-03T18:22:09Z
No. of bitstreams: 2
license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5)
Daniele Kosmo.pdf: 1666129 bytes, checksum: 21d35993408cf04cf3327fefb3c5a4a2 (MD5) / Made available in DSpace on 2018-07-03T18:22:09Z (GMT). No. of bitstreams: 2
license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5)
Daniele Kosmo.pdf: 1666129 bytes, checksum: 21d35993408cf04cf3327fefb3c5a4a2 (MD5)
Previous issue date: 2017-07-07 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O câncer de pulmão está entre os tipos mais comuns dentre todos os tumores malignos. Sendo a quimioterapia o principal tratamento preconizado, todavia além dos seus diferentes efeitos colaterais, verifica-se a resistência a múltiplos fármacos, referida como a perda da sensibilidade tumoral aos agentes quimioterápicos. Óleos essenciais (OE) podem contornar esta refratariedade dos tumores aos fármacos e se apresentam também como alternativa antitumoral, em especial pela possibilidade de serem administrados por via inalatória. O objetivo deste trabalho foi o de avaliar a citotoxicidade da fase vapor do OE de Jasminum officinale em células Calu-3 (adenocarcinoma de câncer de pulmão humano) e células 3T3 (linhagem padrão de fibroblasto murino) bem como investigar as alterações morfológicas e mecanismo de ação deste OE em Calu-3. Foram realizados ensaios de avaliação metabólica com redução de MTT e ensaio de marcação de proteína com SRB, onde verificou-se a redução da viabilidade celular de maneira dose-dependente. A IC50 estimada para células Calu-3 foi de 1495,57 μg/mL e para as células 3T3 foi de 3795,05 μg/mL. Para investigação das alterações morfológicas associados à citotoxicidade, foram avaliados (1) a morfologia celular com o emprego dos corantes alaranjado de acridina, brometo de etídio; (2) distribuição de células entre as fases do ciclo celular com emprego de iodeto de propídio (PI) por citometria de fluxo; e foi avaliado o potencial inibitório da fase vapor do OE de Jasminum officinale na atividade da glicoproteína P empregando o ensaio de acúmulo de Rodamina 123. Os resultados obtidos indicaram que a morte das células foi causada pelo processo de apoptose tardia, inicial e necrose, com pequena redução da porcentagem de células nas fases sub-G0 e G2/M do ciclo celular. A fase vapor do OE de Jasminum officinale apresenta efeito inibitório sobre a atividade da glicoproteína P em sinergia com a curcumina.Tais resultados sugerem a possibilidade da utilização do OE de Jasminum officinale, em sua fase vapor no tratamento do câncer de pulmão por via inalatória, porém ainda são necessários mais estudos para aprofundar o conhecimento sobre óleos essenciais, frente a células normais e tumorais de pulmão, incluindo os mecanismos envolvidos. / Lung cancer is among the most common types among all malignancies, with an increase of 2% per year in its incidence. Chemotherapy is the main treatment recommended, but in addition cause collateral effects and also resistance to multiple drugs can occur, that is, the loss of tumor sensitivity to chemotherapeutic agents. Essential oils (OE) may be an option for this refractoriness of tumors to drugs and also present as an antitumor alternative, especially for the possibility of being administered by inhalation. The objective of this work was to evaluate the cytotoxicity of the vapor phase of jasmine OE in Calu-3 cells (human lung cancer adenocarcinoma) and 3T3 cells (murine fibroblast control line model). The vapor phase of jasmine OE reduces cell viability in a dose-dependent manner, as demonstrated by the MTT and SRB reduction assays. The estimated IC 50 for Calu-3 cells was 1495.57 μg / mL and for 3T3 cells was 3795.05 μg / mL. The possible effects associated with cytotoxicity, (1) cellular morphology, (2) cell cycle phase distribution and (3) P-glycoprotein activity were evaluated. Results indicated that cell death was caused by the late apoptosis and necrosis, reduction in the percentage of cells in the sub-G0 and G2/M cell cycle phases. The vapor phase of the jasmine oil presented an inhibitory effect on the activity of the glycoprotein P in synergy with curcumin. These results suggest the possibility of the use of the OE of jasmine, in its vapor phase in the treatment lung cancer, by inhalation. Further studies are needed to knowledge about essential oils, especially the so-called alternative, against normal and tumor cells of the lung, included the mechanism involved.
|
5 |
Développement de modèles in vitro de la barrière alvéolo-capillaire pour l'étude de la toxicité et du passage des nanoparticules / Development of in vitro models of the alveolo-capillary barrier to study the toxicity and the passage of nanoparticlesDekali, Samir 30 January 2013 (has links)
Après exposition par inhalation, les nanoparticules (NPs) peuvent atteindre les alvéoles pulmonaires, se retrouver au niveau de la barrière alvéolo-capillaire (BAC), et induire une toxicité locale et / ou franchir cette barrière pour se retrouver dans la circulation sanguine. Dans ce contexte, l’objectif de ce travail a été de développer des modèles de co-cultures in vitro simples à mettre en œuvre (utilisation de lignées cellulaires humaines), pour étudier les effets des NPs au niveau de la BAC. Dans un premier temps, des co-cultures de cellules épithéliales alvéolaires ou de phénotype proche (lignées A549 ou NCI-H441), et de macrophages (lignée THP-1), ont permis l’étude des effets pro-inflammatoires des NPs de SiO2 et de TiO2. Avec ces modèles nous avons montré l’importance de la coopération cellulaire mise en jeu lors des processus inflammatoires liés aux NPs, mais aussi le rôle du ratio cellulaire employé dans ces réponses. Dans un second temps, des co-cultures tridimensionnelles en chambres bicamérales associant des macrophages (lignée THP-1), des cellules épithéliales bronchiques (lignée Calu-3), et des cellules endothéliales pulmonaires microvasculaires (lignée HPMEC-ST1.6R), ont permis l’étude de l’impact de NPs fluorescentes de polystyrène sur l’intégrité de la BAC, et leur passage à travers cette barrière. Les cellules épithéliales Calu-3 permettent d’établir une barrière de qualité mais la membrane microporeuse servant de support aux cellules doit être optimisée pour ne pas être un frein au passage des NPs. Ce travail montre qu’un seul modèle ne permet pas d’étudier de façon optimale à la fois la toxicité et la translocation des NPs, et qu’une approche adaptée doit être envisagée en fonction du paramètre que l’on souhaite étudier. / After inhalation, nanoparticles (NPs) can reach the alveoli and the alveolo-capillary barrier (ACB), and consequently induce local toxicity and / or cross this barrier to reach the bloodstream. In this context, the aim of this work was to develop co-culture in vitro models simple to implement (using human cell lines), to study effects of NPs on the ACB. In a first time, pro-inflammatory effects of SiO2 and TiO2 NPs were studied on co-cultures of alveolar epithelial cells (A549 and NCI-H441 cell lines), and macrophages (THP-1 cell line). We demonstrated the importance of cell cooperation during inflammatory processes caused by these NPs, and the role of the cellular ratio in these inflammatory responses. In a second time, effects of fluorescent polystyrene NPs on the ACB integrity, and their translocation were studied on three-dimensional co-cultures in bicameral chambers involving macrophages (THP-1 cell line), bronchial epithelial cells (Calu-3 cell line), and micro-vascular pulmonary endothelial cells (HPMEC ST1.6R cell line). The use of Calu-3 has provided a good barrier, but further investigations on microporous membranes are still needed to not interfere with NPs translocation. Altogether, these results show that a tailored approach should be considered in order to study toxicity or translocation of NPs.
|
6 |
Effects of carbon nanotubes on barrier epithelial cells via effects on lipid bilayersLewis, Shanta January 2013 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Carbon nanotubes (CNTs) are one of the most common nanoparticles (NP) found in workplace air. Therefore, there is a strong chance that these NP will enter the human body. They have similar physical properties to asbestos, a known toxic material, yet there is limited evidence showing that CNTs may be hazardous to human barrier epithelia. In previous studies done in our laboratory, the effects of CNTs on the barrier function in the human airway epithelial cell line (Calu-3) were measured. Measurements were done using electrophysiology, a technique which measures both transepithelial electrical resistance (TEER), a measure of monolayer integrity, and short circuit current (SCC) which is a measure of vectorial ion transport across the cell monolayer. The research findings showed that select physiologically relevant concentrations of long single-wall (SW) and multi-wall (MW) CNTs significantly decreased the stimulated SCC of the Calu-3 cells compared to untreated cultures. Calu-3 cells showed decreases in TEER when incubated for 48 hours (h) with concentrations of MWCNT ranging from 4µg/cm2 to 0.4ng/cm2 and SWCNT ranging from 4µg/cm2 to 0.04ng/cm2. The impaired cellular function, despite sustained cell viability, led us to investigate the mechanism by which the CNTs were affecting the cell membrane. We investigated the interaction of short MWCNTs with model lipid membranes using an ion channel amplifier, Planar Bilayer Workstation. Membranes were synthesized using neutral diphytanoylphosphatidylcholine (DPhPC) and negatively charged diphytanoylphosphatidylserine (DPhPS) lipids. Gramicidin A (GA), an ion channel reporter protein, was used to measure changes in ion channel conductance due to CNT exposures. Synthetic membranes exposed to CNTs allowed bursts of currents to cross the membrane when they were added to the membrane buffer system. When added to the membrane in the presence of GA, they distorted channel formation and reduced membrane stability.
|
7 |
Effects of carbon nanotubes on airway epithelial cells and model lipid bilayers : proteomic and biophysical studiesLi, Pin January 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Carbon nanomaterials are widely produced and used in industry, medicine and scientific research. To examine the impact of exposure to nanoparticles on human health, the human airway epithelial cell line, Calu-3, was used to evaluate changes in the cellular proteome that could account for alterations in cellular function of airway epithelia after 24 h exposure to 10 μg/mL and 100 ng/mL of two common carbon nanoparticles, singleand multi-wall carbon nanotubes (SWCNT, MWCNT). After exposure to the nanoparticles, label-free quantitative mass spectrometry (LFQMS) was used to study differential protein expression. Ingenuity Pathway Analysis (IPA) was used to conduct a bioinformatics analysis of proteins identified by LFQMS. Interestingly, after exposure to a high concentration (10 μg/mL; 0.4 μg/cm2) of MWCNT or SWCNT, only 8 and 13 proteins, respectively, exhibited changes in abundance. In contrast, the abundance of hundreds of proteins was altered in response to a low concentration (100 ng/mL; 4
ng/cm2) of either CNT. Of the 281 and 282 proteins that were significantly altered in response to MWCNT or SWCNT, respectively, 231 proteins were the same.
Bioinformatic analyses found that the proteins common to both kinds of nanotubes are associated with the cellular functions of cell death and survival, cell-to-cell signaling and interaction, cellular assembly and organization, cellular growth and proliferation,
infectious disease, molecular transport and protein synthesis. The decrease in expression of the majority proteins suggests a general stress response to protect cells. The STRING database was used to analyze the various functional protein networks. Interestingly, some
proteins like cadherin 1 (CDH1), signal transducer and activator of transcription 1 (STAT1), junction plakoglobin (JUP), and apoptosis-associated speck-like protein
containing a CARD (PYCARD), appear in several functional categories and tend to be in the center of the networks. This central positioning suggests they may play important roles in multiple cellular functions and activities that are altered in response to carbon
nanotube exposure. To examine the effect of nanotubes on the plasma membrane, we investigated the
interaction of short purified MWCNT with model lipid membranes using a planar bilayer workstation. Bilayer lipid membranes were synthesized using neutral 1, 2-diphytanoylsn-glycero-3-phosphocholine (DPhPC) in 1 M KCl. The ion channel model protein, Gramicidin A (gA), was incorporated into the bilayers and used to measure the effect of MWCNT on ion transport. The opening and closing of ion channels, amplitude of current, and open probability and lifetime of ion channels were measured and analyzed by Clampfit. The presence of an intermediate concentration of MWCNT (2 μg/ml) could be related to a statistically significant decrease of the open probability and lifetime of gA channels.
The proteomic studies revealed changes in response to CNT exposure. An analysis of the changes using multiple databases revealed alterations in pathways, which were
consistent with the physiological changes that were observed in cultured cells exposed to very low concentrations of CNT. The physiological changes included the break down of the barrier function and the inhibition of the mucocillary clearance, both of which could increase the risk of CNT’s toxicity to human health. The biophysical studies indicate MWCNTs have an effect on single channel kinetics of Gramicidin A model cation channel. These changes are consistent with the inhibitory effect of nanoparticles on hormone stimulated transepithelial ion flux, but additional experiments will be necessary to substantiate this correlation.
|
Page generated in 0.0281 seconds