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1.
Beilstein J Nanotechnol ; 14: 804-818, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37533841

RESUMO

Chagas disease is a neglected endemic disease prevalent in Latin American countries, affecting around 8 million people. The first-line treatment, benznidazole (BNZ), is effective in the acute stage of the disease but has limited efficacy in the chronic stage, possibly because current treatment regimens do not eradicate transiently dormant Trypanosoma cruzi amastigotes. Nanostructured lipid carriers (NLC) appear to be a promising approach for delivering pharmaceutical active ingredients as they can have a positive impact on bioavailability by modifying the absorption, distribution, and elimination of the drug. In this study, BNZ was successfully loaded into nanocarriers composed of myristyl myristate/Crodamol oil/poloxamer 188 prepared by ultrasonication. A stable NLC formulation was obtained, with ≈80% encapsulation efficiency (%EE) and a biphasic drug release profile with an initial burst release followed by a prolonged phase. The hydrodynamic average diameter and zeta potential of NLC obtained by dynamic light scattering were approximately 150 nm and -13 mV, respectively, while spherical and well-distributed nanoparticles were observed by transmission electron microscopy. Fourier-transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, and small-angle X-ray scattering analyses of the nanoparticles indicated that BNZ might be dispersed in the nanoparticle matrix in an amorphous state. The mean size, zeta potential, polydispersity index, and %EE of the formulation remained stable for at least six months. The hemolytic effect of the nanoparticles was insignificant compared to that of the positive lysis control. The nanoparticle formulation exhibited similar performance in vitro against T. cruzi compared to free BNZ. No formulation-related cytotoxic effects were observed on either Vero or CHO cells. Moreover, BNZ showed a 50% reduction in CHO cell viability at 125 µg/mL, whereas NLC-BNZ and non-loaded NLC did not exert a significant effect on cell viability at the same concentration. These results show potential for the development of new nanomedicines against T. cruzi.

2.
Front Chem ; 8: 601151, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33324615

RESUMO

Trypanosomatid-caused conditions (African trypanosomiasis, Chagas disease, and leishmaniasis) are neglected tropical infectious diseases that mainly affect socioeconomically vulnerable populations. The available therapeutics display substantial limitations, among them limited efficacy, safety issues, drug resistance, and, in some cases, inconvenient routes of administration, which made the scenarios with insufficient health infrastructure settings inconvenient. Pharmaceutical nanocarriers may provide solutions to some of these obstacles, improving the efficacy-safety balance and tolerability to therapeutic interventions. Here, we overview the state of the art of therapeutics for trypanosomatid-caused diseases (including approved drugs and drugs undergoing clinical trials) and the literature on nanolipid pharmaceutical carriers encapsulating approved and non-approved drugs for these diseases. Numerous studies have focused on the obtention and preclinical assessment of lipid nanocarriers, particularly those addressing the two currently most challenging trypanosomatid-caused diseases, Chagas disease, and leishmaniasis. In general, in vitro and in vivo studies suggest that delivering the drugs using such type of nanocarriers could improve the efficacy-safety balance, diminishing cytotoxicity and organ toxicity, especially in leishmaniasis. This constitutes a very relevant outcome, as it opens the possibility to extended treatment regimens and improved compliance. Despite these advances, last-generation nanosystems, such as targeted nanocarriers and hybrid systems, have still not been extensively explored in the field of trypanosomatid-caused conditions and represent promising opportunities for future developments. The potential use of nanotechnology in extended, well-tolerated drug regimens is particularly interesting in the light of recent descriptions of quiescent/dormant stages of Leishmania and Trypanosoma cruzi, which have been linked to therapeutic failure.

3.
Front Mol Biosci ; 7: 587997, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33195435

RESUMO

In the golden age of pharmaceutical nanocarriers, we are witnessing a maturation stage of the original concepts and ideas. There is no doubt that nanoformulations are extremely valuable tools for drug delivery applications; the current challenge is how to optimize them to ensure that they are safe, effective and scalable, so that they can be manufactured at an industrial level and advance to clinical use. In this context, lipid nanoparticles have gained ground, since they are generally regarded as non-toxic, biocompatible and easy-to-produce formulations. Pharmaceutical applications of lipid nanocarriers are a burgeoning field for the transport and delivery of a diversity of therapeutic agents, from biotechnological products to small drug molecules. This review starts with a brief overview of the characteristics of solid lipid nanoparticles and discusses the relevancy of performing systematic preformulation studies. The main applications, as well as the advantages that this type of nanovehicles offers in certain therapeutic scenarios are discussed. Next, pharmacokinetic aspects are described, such as routes of administration, absorption after oral administration, distribution in the organism (including brain penetration) and elimination processes. Safety and toxicity issues are also addressed. Our work presents an original point of view, addressing the biopharmaceutical aspects of these nanovehicles by means of descriptive statistics of the state-of-the-art of solid lipid nanoparticles research. All the presented results, trends, graphs and discussions are based in a systematic (and reproducible) bibliographic search that considered only original papers in the subject, covering a 7 years range (2013-today), a period that accounts for more than 60% of the total number of publications in the topic in the main bibliographic databases and search engines. Focus was placed on the therapeutic fields of application, absorption and distribution processes and current efforts for the translation into the clinical practice of lipid-based nanoparticles. For this, the currently active clinical trials on lipid nanoparticles were reviewed, with a brief discussion on what achievements or milestones are still to be reached, as a way of understanding the reasons for the scarce number of solid lipid nanoparticles undergoing clinical trials.

4.
Ciencia Reguladora ; (6): 32-37, Abr2020. ilus
Artigo em Espanhol | BINACIS | ID: biblio-1102040

RESUMO

La enfermedad de Chagas, tripanosomiasis americana o simplemente Chagas, es una infección parasitaria que afecta a más de 8 millones de personas a nivel mundial. La Organización Mundial de la Salud ha incluido a esta patología dentro de la categoría de enfermedades tropicales desatendidas (junto a la malaria, leishmaniasis y dengue, entre otras), ya que afecta mayoritariamente a grupos vulnerables de la sociedad sin acceso a condiciones adecuadas de sanidad ni tratamientos médicos, y en contacto continuo con los vectores de contagio. La terapia actual incluye fármacos utilizados desde hace ya más de 50 años que, si bien son efectivos en la fase inicial de la enfermedad, fallan en la erradicación total del parásito, a la vez que generan graves efectos adversos. En vista de este panorama, surge la necesidad de nuevas estrategias de bajo costo para optimizar la terapia. Una posible alternativa para mejorar el tratamiento, diagnóstico y prevención surge desde la nanotecnología: el presente artículo revisa el estado actual de la investigación de nanomedicinas para tratar la enfermedad de Chagas. Cabe mencionar que, si bien se ha avanzado enormemente en dirección a una terapia que disminuya los efectos adversos de la droga, aún no se ha logrado diseñar y producir un nanovehículo farmacéutico óptimo contra el agente etiológico de la enfermedad.


Chagas disease, American trypanosomiasis or Chagas disease, is a parasitic infection that affects more than 8 million people worldwide. This pathology was included by the World Health Organization within the category of neglected tropical diseases (along with malaria, leishmaniasis and dengue, among others), since it mainly affects vulnerable groups in society without access to adequate health conditions nor medical treatments, and in continuous contact with the transmission vectors. Current therapy includes drugs used for more than 50 years that, although effective in the initial phase of the disease, fail in the total eradication of the parasite, while generating serious adverse effects. In light of this situation, new low-cost approach strategies are necessary to optimize therapy. A possible alternative to improve treatment, diagnosis and prevention arises from nanotechnology: this article reviews the current state of research in nanomedicines to treat Chagas disease. It is worth mentioning that, although great progress has been made towards a therapy that reduces the adverse effects of the drug, it has not yet been possible to design and produce an optimal pharmaceutical nanovehicle against the etiologic agent of the disease.


Assuntos
Veículos Farmacêuticos , Doença , Doença de Chagas , Nanomedicina
5.
PLoS One ; 14(6): e0216817, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31233528

RESUMO

Biofilms are microbial communities encased in a protective matrix composed of exopolymeric substances including exopolysaccharides, proteins, lipids, and extracellular DNA. Biofilms cause undesirable effects such as biofouling, equipment damage, prostheses colonization, and disease. Biofilms are also more resilient than free-living cells to regular decontamination methods and therefore, alternative methods are needed to eradicate them. The use of non-thermal atmospheric pressure plasmas is a good alternative as plasmas contain reactive species, free radicals, and UV photons well-known for their decontamination potential against free microorganisms. Pseudomonas aeruginosa biofilms colonize catheters, indwelling devices, and prostheses. Plasma effects on cell viability have been previously documented for P. aeruginosa biofilms. Nonetheless, the effect of plasma on the biofilm matrix has received less attention and there is little evidence regarding the changes the matrix undergoes. The aim of this work was to study the effect plasma exerts mostly on the P. aeruginosa biofilm matrix and to expand the existing knowledge about its effect on sessile cells in order to achieve a better understanding of the mechanism/s underlying plasma-mediated biofilm inactivation. We report a reduction in the amount of the biofilm matrix, the loss of its tridimensional structure, and morphological changes in sessile cells at long exposure times. We show chemical and structural changes on the biofilm matrix (mostly on carbohydrates and eDNA) and cells (mostly on proteins and lipids) that are more profound with longer plasma exposure times. We also demonstrate the presence of lipid oxidation products confirming cell membrane lipid peroxidation as plasma exposure time increases. To our knowledge this is the first report providing detailed evidence of the variety of chemical and structural changes that occur mostly on the biofilm matrix and sessile cells as a consequence of the plasma treatment. Based on our results, we propose a comprehensive model explaining plasma-mediated biofilm inactivation.


Assuntos
Biofilmes/efeitos dos fármacos , Modelos Biológicos , Gases em Plasma/farmacologia , Pseudomonas aeruginosa/citologia , Pseudomonas aeruginosa/fisiologia , Pressão Atmosférica , Biofilmes/crescimento & desenvolvimento , Pseudomonas aeruginosa/efeitos dos fármacos , Fatores de Tempo
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