Epidermal growth factor alters silica nanoparticle uptake and improves gold-nanoparticle-mediated gene silencing in A549 cells

Introduction: Delivery of therapeutic nanoparticles (NPs) to cancer cells represents a promising approach for biomedical applications. A key challenge for nanotechnology translation from the bench to the bedside is the low amount of administered NPs dose that effectively enters target cells. To improve NPs delivery, several studies proposed NPs conjugation with ligands, which specifically deliver NPs to target cells via receptor binding. One such example is epidermal growth factor (EGF), a peptide involved in cell signaling pathways that control cell division by binding to epidermal growth factor receptor (EGFR). However, very few studies assessed the influence of EGF present in the cell environment, on the cellular uptake of NPs.Methods: We tested if the stimulation of EGFR-expressing lung carcinomacells A549 with EGF affects the uptake of 59 nm and 422 nm silica (SiO2) NPs. Additionally, we investigated whether the uptake enhancement can be achieved with gold NPs, suitable to downregulate the expression of cancer oncogene c-MYC.Results: Our findings show that EGF binding to its receptor results in receptor autophosphorylation and initiate signaling pathways, leading to enhanced endocytosis of 59 nm SiO2 NPs, but not 422 nm SiO2 NPs. Additionally, we demonstrated an enhanced gold (Au) NPs endocytosis and subsequently a higher downregulation of c-MYC.Discussion: These findings contribute to a better understanding of NPs uptake in the presence of EGF and that is a promising approach for improved NPs delivery

Aportes al desarrollo de un sistema nanoestructurado incorporando un extracto de frutos de Physalis peruviana con posible actividad antidiabética

Se prepararon nanopartículas poliméricas (NPs) a partir de un copolímero de mPEG-b-PCL de ~46 kDa, vacías y cargadas con un extracto etanólico estandarizado de frutos de Physalis peruviana, mediante una metodología modificada de doble emulsificación evaporación del solvente, utilizando como estabilizantes de la segunda emulsión PVA 2 %, mPEG-b-PCL de 8 KDa a diferentes concentraciones: 0.01, 0.03, 0.05, 0.1 %. Para la elaboración de las nanopartículas tanto vacías como con el extracto, se realizaron las siguientes etapas de investigación: la primera consistió en la obtención de materiales, así se llevó a cabo la síntesis del copolímero de mPEG-b-PCL~46 KDa por apertura de anillo, el cual fue caracterizado por espectroscopia Infrarroja (FT-IR), resonancia magnética nuclear (RMN) y calorimetría diferencial de barrido (DSC). Asimismo, se obtuvo el extracto etanólico estandarizado de frutos de Physalis peruviana, el cual fue caracterizado con su índice de refracción y sólidos totales; además se identificó una molécula trazadora de este por RMN, y se evaluó su actividad biológica in vitro mediante la evaluación del efecto sobre la actividad de la enzima alfa amilasa. Seguido de esto, ya con las materias primas obtenidas, se continuó con dos etapas más: en primer lugar, la elaboración de las NPs copoliméricas vacías variando el tipo de estabilizante de la segunda emulsión, realizando su caracterización de forma (TEM), tamaño, índice de polidispersidad y potencial ζ (DLS); el segundo paso correspondió a la realización de las NPs cargadas con el extracto etanólico, estas fueron caracterizadas de la misma forma que las NPs vacías. Para conocer la influencia del agente estabilizante en la encapsulación del extracto de frutos de Physalis peruviana, se emplearon las pruebas de DSC e IR y se confirmó la carga del extracto dentro de las nanopartículas por RMN. Como resultado, se obtuvieron nanopartículas esféricas de tamaños comprendidos entre aproximadamente 150 nm a 250 nm. Un potencial ζ entre aproximadamente -10 y -23 mV. El PdI estuvo en un rango de 0.146 a 0.280, sugiriendo una distribución ligeramente polidispersa. Además, se compararon los resultados del extracto libre (no encapsulado) con el extracto etanólico una vez liberado de las NPs mediante un estudio de liberación por membrana de diálisis de 3500 Da, al cual se le hizo seguimiento durante 72 h, evaluando su efecto en el porcentaje de inhibición de la alfa amilasa. Adicionalmente, el estudio de la liberación se complementó al evaluar el contenido de azúcares reductores en función del tiempo. De esa manera se demostró su posible actividad antidiabética.It was done polymeric nanoparticles (NPs) based on copolymer of mPEG-b-PCL of ~46 kDa, empty and loaded with and standard ethanolic extract made of the fruit Physalis peruviana, with a modified methodology by double solvent evaporation emulsification, using 2% PVA and 8 KDa mPEG-b-PCL as stabilizers of the second emulsion, at different concentrations: 0.01, 0.03, 0.05, 0.1%. For the elaboration of the nanoparticles both empty and with the extract, the following investigation stages were carried out: the first one It consisted of obtaining materials, thus the synthesis of the mPEG-b-PCL copolymer ~46 KDa was carried out by opening of ring, which it was characterized by Infrared spectroscopy (FT-IR), nuclear magnetic resonance imaging (NMR) and differential scanning calorimetry (DSC). Likewise, the standardized ethanolic extract of Physalis peruviana fruits was obtained, which it was characterized with its refractive index and total solids; In addition, a tracer molecule was identified by NMR and its biological activity was evaluated in vitro by evaluating the effect on the activity of the enzyme alpha amylase. Following this, with the raw materials obtained, two more stages were continued: first, the elaboration of the empty copolymeric NPs it was varying the type of stabilizer of the second emulsion, making its characterization of form (TEM), size, polydispersity index and potential ζ (DLS); the second step corresponded to the realization of the NPs loaded with the ethanolic extract, these were characterized in the same way as the empty NPs. In order to know the influence of the stabilizing agent on the encapsulation of the Physalis peruviana fruit extract, the DSC and IR tests were used and the loading of the extract into the nanoparticles was confirmed by NMR. As a result, spherical nanoparticles of sizes between about 150 nm to 250 nm were obtained. A potential ζ between approximately -10 and -23 mV. The PdI was in the range of 0.146 to 0.280, suggesting a slightly polydisperse distribution. In addition, the results of the free extract (not encapsulated) were compared with the ethanolic extract once released from the NPs by a release study with a 3500 Da dialysis membrane, which it was monitored for 72 hours, evaluating its effect on percent inhibition of alpha amylase. Additionally, the study of the release was complemented by evaluating the content of reducing sugars as a function of time. In that way its possible antidiabetic activity was demonstrated.MincienciasContrato 187-2019Magíster en Ciencias Farmacéuticas. Línea de Investigación: Diseño y desarrollo de productos fitofarmacéuticosMaestrí

DataSheet1_Epidermal growth factor alters silica nanoparticle uptake and improves gold-nanoparticle-mediated gene silencing in A549 cells.docx

Introduction: Delivery of therapeutic nanoparticles (NPs) to cancer cells represents a promising approach for biomedical applications. A key challenge for nanotechnology translation from the bench to the bedside is the low amount of administered NPs dose that effectively enters target cells. To improve NPs delivery, several studies proposed NPs conjugation with ligands, which specifically deliver NPs to target cells via receptor binding. One such example is epidermal growth factor (EGF), a peptide involved in cell signaling pathways that control cell division by binding to epidermal growth factor receptor (EGFR). However, very few studies assessed the influence of EGF present in the cell environment, on the cellular uptake of NPs.Methods: We tested if the stimulation of EGFR-expressing lung carcinomacells A549 with EGF affects the uptake of 59 nm and 422 nm silica (SiO2) NPs. Additionally, we investigated whether the uptake enhancement can be achieved with gold NPs, suitable to downregulate the expression of cancer oncogene c-MYC.Results: Our findings show that EGF binding to its receptor results in receptor autophosphorylation and initiate signaling pathways, leading to enhanced endocytosis of 59 nm SiO2 NPs, but not 422 nm SiO2 NPs. Additionally, we demonstrated an enhanced gold (Au) NPs endocytosis and subsequently a higher downregulation of c-MYC.Discussion: These findings contribute to a better understanding of NPs uptake in the presence of EGF and that is a promising approach for improved NPs delivery.</p