37 research outputs found

    Synergistic Photothermal-Chemotherapy Based on the Use of Biomimetic Magnetic Nanoparticles

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    MamC-mediated biomimetic magnetic nanoparticles (BMNPs) have emerged as one of the most promising nanomaterials due to their magnetic features (superparamagnetic character and large magnetic moment per particle), their novel surface properties determined by MamC, their biocompatibility and their ability as magnetic hyperthermia agents. However, the current clinical application of magnetic hyperthermia is limited due to the fact that, in order to be able to reach an effective temperature at the target site, relatively high nanoparticle concentration, as well as high magnetic field strength and/or AC frequency are needed. In the present study, the potential of BMNPs to increase the temperature upon irradiation of a laser beam in the near infrared, at a wavelength at which tissues become partially transparent, is explored. Moreover, our results also demonstrate the synergy between photothermia and chemotherapy in terms of drug release and cytotoxicity, by using BMNPs functionalized with doxorubicin, and the effectiveness of this combination therapy against tumor cells in in vitro experiments. Therefore, the findings of the present study open the possibility of a novel, alternative approach to fight localized tumors.Ministerio de Economía y Competitividad (CGL2016- 76723 and PID2019-109294RB-100 projects)Ramón y Cajal program (RYC-2014-16901)Junta de Andalucía. Programa Operativo FEDER 2014–2020. (A1-FQM-341-UGR18, C-FQM-497-UGR18, A-BIO376-UGR18).Andalusian regional government (CTS-236)Formación de Doctores 2018 grant (ref. PRE2018-085440) from the Ministerio de Ciencia, Innovación y Universidades (Spain)Unidad Cientifica de Excelencia UCE-PP2016-05Instituto de Biotecnología of the University of Granad

    Reactive oxygen species (ROS) production in HepG2 cancer cell line through the application of localized alternating magnetic field

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    This research work is supported by Ministerio de Economia y Competitividad (CGL2016-76723 project), Ramon y Cajal programme (RYC-2014-16901), Junta de Andalucia. Programa Operativo FEDER 2014-2020. (A1-FQM-341-UGR18, C-FQM-497-UGR18, A-BIO-376-UGR18). This research was also aided by the Andalusian regional government (CTS-236). Alberto Sola-Leyva holds a Formacion de Doctores 2018 grant (ref. PRE2018-085440) from the Ministerio de Ciencia, Innovacion y Universidades (Spain). Ylenia Jabalera wants to acknowledge a FPU2016 grant (ref. FPU16_04580) from the Ministerio de Educacion, Ciencia y Deporte y Competitividad (Spain) and Unidad Cientifica de Excelencia UCE-PP2016-05 of the University of Granada. This study is part of a PhD Thesis conducted at the University of Granada, Spain. Finally, thanks go to the CIC personnel of the University of Granada for technical assistance in the TEM.Recent studies have shown the potential of magnetic hyperthermia in cancer treatments. However, the underlying mechanisms involved have not been yet fully described. In particular, the cell death related to magnetic hyperthermia observed in cultures incubated with low concentration of magnetic nanoparticles and under a low intensity alternating magnetic field, in which a macroscopic temperature rise is not observed, is still not understood. In the present study, we investigate the production of intracellular Reactive Oxygen Species (ROS) as a mechanism to induce cell death under these conditions. In this study, the production and influence of ROS on the viability of HepG2 human hepatoma cells (used as a model cell line) are analyzed under the application of variable magnetic fields using hyperthermia agents, such as biomimetic magnetic nanoparticles (BMNPs) mediated by magnetosome MamC protein fromMagnetococcus marinusMC-1. The results show that intracellular ROS production increases up to similar to 90% following upon the exposure of AMF to HepG2 cells containing BMNPs, which could determine the loss of cell viability (up to similar to 40% reduction) without a significant rise in temperature. Such ROS production is linked to mitochondrial dysfunction caused by the application of AMF to cells containing BMNPs.Spanish Government CGL2016-76723Spanish Government RYC-2014-16901Junta de AndaluciaPrograma Operativo FEDER 2014-2020 A1-FQM-341-UGR18 C-FQM-497-UGR18 A-BIO-376-UGR18Andalusian regional government CTS-236Ministerio de Ciencia, Innovacion y Universidades (Spain) PRE2018-085440Ministerio de Educacion, Ciencia y Deporte y Competitividad (Spain) FPU16_04580Unidad Cientifica de Excelencia of the University of Granada UCE-PP2016-0

    Improving the Cellular Uptake of Biomimetic Magnetic Nanoparticles

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    This research was funded by the FUR (Fondo Unico della Ricerca—University of Verona) of M. Perduca. C.J.-L. acknowledges funding from projects CGL2016-76723 from the Ministerio de Economía y Competitividad from Spain and Fondo Europeo de Desarrollo Regional (FEDER) and Programa Operativo FEDER 2014–2020 (A-BIO-376-UGR18) Junta de Andalucia. M.P.C.-J. acknowledges funding from projects PID2019-109294RB-100 from the Ministerio de Ciencia e Innovación from Spain.We are grateful to the “Centro Piattaforme Tecnologiche” of the University of Verona for giving access to DLS equipment. CJL acknowledges. the Unidad Cientıfica de Excelencia UCE PP 2016.05 (U. Granada) and Instituto de Biotecnología. Y.J. wants to acknowledge a FPU2016 grant (ref. FPU16_04580) from the Ministerio de Educación, Ciencia y Deporte y Competitividad (Spain). AS-L is funded by the Spanish Ministry of Science, Innovation and Universities: Formación de Doctores 2018 (ref. PRE2018-0854409). Thanks go to the Scientific Instrumentation Center (CIC) personnel of the University of Granada for technical assistance with the TEM.We also thank Salvatore Calogero Gaglio for his help in preparing Figure S4.Magnetococcus marinus magnetosome-associated protein MamC, expressed as recombinant, has been proven to mediate the formation of novel biomimetic magnetic nanoparticles (BMNPs) that are successful drug nanocarriers for targeted chemotherapy and hyperthermia agents. These BMNPs present several advantages over inorganic magnetic nanoparticles, such as larger sizes that allow the former to have larger magnetic moment per particle, and an isoelectric point at acidic pH values, which allows both the stable functionalization of BMNPs at physiological pH value and the molecule release at acidic (tumor) environments, simply based on electrostatic interactions. However, difficulties for BMNPs cell internalization still hold back the efficiency of these nanoparticles as drug nanocarriers and hyperthermia agents. In the present study we explore the enhanced BMNPs internalization following upon their encapsulation by poly (lactic-co-glycolic) acid (PLGA), a Food and Drug Administration (FDA) approved molecule. Internalization is further optimized by the functionalization of the nanoformulation with the cell-penetrating TAT peptide (TATp). Our results evidence that cells treated with the nanoformulation [TAT-PLGA(BMNPs)] show up to 80% more iron internalized (after 72 h) compared to that of cells treated with BMNPs (40%), without any significant decrease in cell viability. This nanoformulation showing optimal internalization is further characterized. In particular, the present manuscript demonstrates that neither its magnetic properties nor its performance as a hyperthermia agent are significantly altered due to the encapsulation. In vitro experiments demonstrate that, following upon the application of an alternating magnetic field on U87MG cells treated with BMNPs and TAT-PLGA(BMNPs), the cytotoxic effect of BMNPs was not affected by the TAT-PLGA enveloping. Based on that, difficulties shown in previous studies related to poor cell uptake of BMNPs can be overcome by the novel nanoassembly described here.FUR (Fondo Unico della Ricerca-University of Verona)Ministerio de Economia y Competitividad from Spain CGL2016-76723European Commission CGL2016-76723Junta de Andalucia A-BIO-376-UGR18Spanish Government PID2019-109294RB-10

    Embedding Biomimetic Magnetic Nanoparticles Coupled with Peptide AS-48 into PLGA to Treat Intracellular Pathogens

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    Among the strategies employed to overcome the development of multidrug-resistant bacteria, directed chemotherapy combined with local therapies (e.g., magnetic hyperthermia) has gained great interest. A nano-assembly coupling the antimicrobial peptide AS-48 to biomimetic magnetic nanoparticles (AS-48-BMNPs) was demonstrated to have potent bactericidal effects on both Gram-positive and Gram-negative bacteria when the antimicrobial activity of the peptide was combined with magnetic hyperthermia. Nevertheless, intracellular pathogens remain challenging due to the difficulty of the drug reaching the bacterium. Thus, improving the cellular uptake of the nanocarrier is crucial for the success of the treatment. In the present study, we demonstrate the embedding cellular uptake of the original nano-assembly into THP-1, reducing the toxicity of AS-48 toward healthy THP-1 cells. We optimized the design of PLGA[AS-48-BMNPs] in terms of size, colloidal stability, and hyperthermia activity (either magnetic or photothermal). The stability of the nano-formulation at physiological pH values was evaluated by studying the AS-48 release at this pH value. The influence of pH and hyperthermia on the AS-48 release from the nano-formulation was also studied. These results show a slower AS-48 release from PLGA[AS-48-BMNPs] compared to previous nano-formulations, which could make this new nano-formulation suitable for longer extended treatments of intracellular pathogens. PLGA[AS-48-BMNPs] are internalized in THP-1 cells where AS-48 is liberated slowly, which may be useful to treat diseases and prevent infection caused by intracellular pathogens. The treatment will be more efficient combined with hyperthermia or photothermia.FEDER Operational ProgramProyectos de I + D + I, del Plan Andaluz de Investigacion, Desarrollo e Innovacion B-BIO-432-UGR20 B-BIO-268-UGR20 B-CTS-216-UGR20 A-FQM-492-UGR20Instituto de Salud Carlos III European Commission P20-00346 P20_00339 P20-00233Spanish Government PI20-01658Federation of European Microbiological Societies (FEMS) EC2019-005930-P PDC2021-121135.100 FEMS-GO-2020-20

    Combined Magnetic Hyperthermia and Photothermia with Polyelectrolyte/Gold-Coated Magnetic Nanorods

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    Magnetite nanorods (MNRs) are synthesized based on the use of hematite nanoparticles of the desired geometry and dimensions as templates. The nanorods are shown to be highly monodisperse, with a 5:1 axial ratio, and with a 275 nm long semiaxis. The MNRs are intended to be employed as magnetic hyperthermia and photothermia agents, and as drug vehicles. To achieve a better control of their photothermia response, the particles are coated with a layer of gold, after applying a branched polyethyleneimine (PEI, 2 kDa molecular weight) shell. Magnetic hyperthermia is performed by application of alternating magnetic fields with frequencies in the range 118-210 kHz and amplitudes up to 22 kA/m. Photothermia is carried out by subjecting the particles to a near-infrared (850 nm) laser, and three monochromatic lasers in the visible spectrum with wavelengths 480 nm, 505 nm, and 638 nm. Best results are obtained with the 505 nm laser, because of the proximity between this wavelength and that of the plasmon resonance. A so-called dual therapy is also tested, and the heating of the samples is found to be faster than with either method separately, so the strengths of the individual fields can be reduced. Due to toxicity concerns with PEI coatings, viability of human hepatoblastoma HepG2 cells was tested after contact with nanorod suspensions up to 500 mu g/mL in concentration. It was found that the cell viability was indistinguishable from control systems, so the particles can be considered non-cytotoxic in vitro. Finally, the release of the antitumor drug doxorubicin is investigated for the first time in the presence of the two external fields, and of their combination, with a clear improvement in the rate of drug release in the latter case.Ministry of Science and Innovation, Spain (MICINN) EQC2019-005930-PSpanish Government PID2019109294RB-100Junta de AndaluciaEuropean CommissionConsejeria de Economia y Conocimiento/Proyectos de I + D + I del Plan Andaluz de Investigacion, Desarrollo e Innovacion/Grants P20_00346, P20_0023

    Choline kinase inhibitors EB-3D and EB-3P interferes with lipid homeostasis in HepG2 cells

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    A full understanding of the molecular mechanism of action of choline kinase α (ChoKα) inhibitors at the cell level is essential for developing therapeutic and preventive approaches for cancer. The aim of the present study was to evaluate the effects of the ChoKα inhibitors EB-3D and EB-3P on lipid metabolism in HepG2 cells. We used [methyl-14C]choline, [1,2-14C]acetic acid and [2-3H]glycerol as exogenous precursors of the corresponding phospholipids and neutral lipids. [Methyl-14C]choline was also used to determine choline uptake. Protein levels were determined by Western blot. Ultrastructural alterations were investigated by transmission electron microscopy. In this work, we demonstrate that EB-3D and EB-3P interfere with phosphatidylcholine biosynthesis via both CDP-choline pathway and choline uptake by the cell. Moreover, the synthesis of both diacylglycerols and triacylglycerols was affected by cell exposure to both inhibitors. These effects were accompanied by a substantial decrease in cholesterol biosynthesis, as well as alterations in the expression of proteins related to cholesterol homeostasis. We also found that EB-3D and EB-3P lowered ChoKα protein levels. All these effects could be explained by the modulation of the AMP-activated protein kinase signalling pathway. We show that both inhibitors cause mitochondrial alteration and an endoplasmic reticulum stress response. EB-3D and EB-3P exert effects on ChoKα expression, AMPK activation, apoptosis, endoplasmic reticulum stress and lipid metabolism. Taken together, results show that EB-3D and EB-3P have potential anticancer activity through the deregulation of lipid metabolism.This work was aided by the Andalusian Regional Government (P11-CVI-7859). The inhibitors were developed under the Cei-Biotic Project CEI2013-MP-1 (University of Granada)

    Needs of patients with multi-morbidity and heart failure for the development of a mHealth to improve their self-management: A qualitative analysis

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    Objective: To provide practical information regarding needs, preferences of content and format of an app to assist the self-management in patients with multi-morbidity and heart failure (HF). Methods: The three-phase study was conducted in Spain. Six integrative reviews, a qualitative methodology based on Van Manen's hermeneutic phenomenology through semi-structured interviews and user stories were used. Data collection continued until data saturation was reached. All data were transcribed verbatim and analysed using a framework approach. Thematic analysis technique following the methods of Braun and Clarke was used for emerging themes. Results: Integrative reviews conducted included practical recommendations to include in the content and format of the App and helped create the interview guide. Interviews revealed 15 subthemes that captured the meaning of narratives offering contextual insights into the development of the App. The main effective mechanisms of multicomponent interventions for patients with HF must contain (a) components that increase the patient's understanding of HF, (b) self-care, (c) self-efficacy and participation of the family/informal caregiver, (4) psychosocial well-being and (5) professional support and use of technology. User stories revealed that patients prioritized improvements in direct contact with health services in case of emergency (90%), nutritional information (70%), type of exercises in order to improve their physical condition (75%) and information about food and drug interaction (60%). The importance of motivation messages (60%) was highlighted by transversal way. Conclusions: The three-phase process integrating theoretical basis, evidence from integrative reviews and research findings from target users has been considered a guide for future app development17 página

    Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)

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    Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters. Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs). Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001). Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio

    Precariedad, exclusión social y diversidad funcional (discapacidad): lógicas y efectos subjetivos del sufrimiento social contemporáneo (II). Innovación docente en Filosofía

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    El PIMCD "Precariedad, exclusión social y diversidad funcional (discapacidad): lógicas y efectos subjetivos del sufrimiento social contemporáneo (II). Innovación docente en Filosofía" se ocupa de conceptos generalmente eludidos por la tradición teórica (contando como núcleos aglutinantes los de la precariedad laboral, la exclusión social y diversidad funcional o discapacidad), cuyo análisis propicia nuevas prácticas en la enseñanza universitaria de filosofía, adoptando como meta principal el aprendizaje centrado en el estudiantado, el diseño de nuevas herramientas de enseñanza y el fomento de una universidad inclusiva. El proyecto cuenta con 26 docentes de la UCM y otros 28 docentes de otras 17 universidades españolas (UV, UNED, UGR, UNIZAR, UAH, UC3M, UCA, UNIOVI, ULL, EHU/UPV, UA, UAM, Deusto, IFS/CSIC, UCJC, URJC y Univ. Pontificia de Comillas), que permitirán dotar a las actividades programadas de un alcance idóneo para consolidar la adquisición de competencias argumentativas y dialécticas por parte de lxs estudiantes implicados en el marco de los seminarios previstos. Se integrarán en el PIMCD, aparte de PDI, al menos 26 estudiantes de máster y doctorado de la Facultad de Filosofía, a lxs que acompañarán durante el desarrollo del PIMCD 4 Alumni de la Facultad de Filosofía de la UCM, actualmente investigadores post-doc y profesorxs de IES, cuya experiencia será beneficiosa para su introducción en la investigación. Asimismo, el equipo cuenta con el apoyo de varixs profesorxs asociadxs, que en algunos casos son también profesores de IES. Varixs docentes externos a la UCM participantes en el PIMCD poseen una dilatada experiencia en la coordinación de proyectos de innovación de otras universidades, lo que redundará en beneficio de las actividades a desarrollar. La coordinadora y otrxs miembros del PIMCD pertenecen a la Red de Innovación Docente en Filosofia (RIEF), puesta en marcha desde la Universitat de València (http://rief.blogs.uv.es/encuentros-de-la-rief/), a la que mantendremos informada de las actividades realizadas en el proyecto. Asimismo, lxs 6 miembros del PAS permitirán difundir debidamente las actividades realizadas en el PIMCD entre lxs estudiantes Erasmus IN del curso 2019/20 en la Facultad de Filosofía, de la misma manera que orientar en las tareas de maquetación y edición que puedan ser necesarias de cara a la publicación de lxs resultados del PIMCD y en las tareas de pesquisa bibliográfica necesarias para el desarrollo de los objetivos propuestos. Han manifestado su interés en los resultados derivados del PIMCD editoriales especializadas en la difusión de investigaciones predoctorales como Ápeiron y CTK E-Books
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