ImprimirPUBLICATIONS
Iontophoresis-driven alterations in nanoparticle uptake pathway and intracellular trafficking in carcinoma skin cancer cells
Gabriela Fávero Galvão, Raquel Petrilli, Vanessa Cristina Arfelli, Andréia Nogueira Carvalho, Yugo Araújo Martins, Roberta Ribeiro Costa Rosales, Leticia Fröhlich Archangelo, Luis Lamberti Pinto daSilva, Renata Fonseca Vianna Lopez
Abstract
Effective treatment of squamous cell carcinoma (SCC) poses challenges due to intrinsic drug resistance and limited drug penetration into tumor cells. Nanoparticle-based drug delivery systems have emerged as a promising approach to enhance therapeutic efficacy; however, they often face hurdles such as inadequate cellular uptake and rapid lysosomal degradation. This study explores the potential of iontophoresis to augment the efficacy of liposome and immunoliposome-based drug delivery systems for SCC treatment. The study assessed iontophoresis effects on SCC cell line (A431) viability, nanoparticle uptake dynamics, and intracellular distribution patterns. Specific inhibitors were employed to delineate cellular internalization pathways, while fluorescence microscopy and immunohistochemistry examined changes in EGFR expression and lysosomal activity. Results demonstrated that iontophoresis significantly increased cellular uptake of liposomes and immunoliposomes, achieving approximately 50 % uptake compared to 10 % with passive treatment. This enhancement correlated with modifications in endocytic pathways, favoring macropinocytosis and caveolin-mediated endocytosis for liposomes, and macropinocytosis and clathrin-mediated pathways for immunoliposomes. Moreover, iontophoresis induced alterations in EGFR distribution and triggered syncytium-like cellular clustering. It also attenuated lysosomal activity, thereby reducing nanoparticle degradation and prolonging intracellular retention of therapeutic agents. These findings underscore the role of iontophoresis in modulating nanoparticle internalization pathways, offering insights that could advance targeted drug delivery strategies and mitigate therapeutic resistance in SCC and other malignancies.
Keywords: EGFR; Lysosome degradation; Endocytic routes
Electrostimulable polymeric films with hyaluronic acid and lipid nanoparticles for simultaneous topical delivery of macromolecules and lipophilic drugs
Abstract
This study focused on developing electrically stimulable hyaluronic acid (HA) films incorporating lipid nanoparticles (NPs) designed for the topical administration of lipophilic drugs and macromolecules. Based on beeswax and medium-chain triglycerides, NPs were successfully integrated into silk fibroin/chitosan films containing HA (NP-HA films) at a density of approximately 1011 NP/cm2, ensuring a uniform distribution. This integration resulted in a 40% increase in film roughness, a twofold decrease in Young’s modulus, and enhanced film flexibility and bioadhesion work. The NP-HA films, featuring Ag/AgCl electrodes, demonstrated the capability to conduct a constant electrical current of 0.2 mA/cm2 without inducing toxicity in keratinocytes and fibroblasts during a 15-min application. Moreover, the NPs facilitated the homogeneous distribution of lipophilic drugs within the film, effectively transporting them to the skin and uniformly distributing them in the stratum corneum upon film administration. The sustained release of HA from the films, following Higuchi kinetics, did not alter the macroscopic characteristics of the film. Although anodic iontophoresis did not noticeably affect the release of HA, it did enhance its penetration into the skin. This enhancement facilitated the permeation of HA with a molecular weight (MW) of up to 2 × 105 through intercellular and transcellular routes. Confocal Raman spectroscopy provided evidence of an approximate 100% increase in the presence of HA with a MW in the range of 1.5-1.8 × 106 in the viable epidermis of human skin after only 15 min of iontophoresis applied to the films. Combining iontophoresis with NP-HA films exhibits substantial potential for noninvasive treatments focused on skin rejuvenation and wound healing.
Keywords: Hyaluronic acid and iontophoresis; Lipid nanoparticles; Polymeric films.
© 2024. Controlled Release Society.
Liquid crystalline nanogel targets skin cancer via low-frequency ultrasound treatment
Tatiana Aparecida Pereira a, Danielle Nishida Ramos a, Lays Martin Sobral a, Yugo Araújo Martins a, Raquel Petrilli a b, Márcia de Abreu Carvalho Fantini c, Andréia Machado Leopoldino a, Renata Fonseca Vianna Lopez a
Abstract
The potential of low-frequency ultrasound (LFU) combined with nanotechnology-based formulations in improving skin tumors topical treatment was investigated. The impact of solid lipid nanoparticles (SLN) and hydrophilic nanogels as coupling media on LFU-induced skin localized transport regions (LTR) and the penetration of doxorubicin (DOX) in LFU-pretreated skin was evaluated. SLN were prepared by the microemulsion technique and liquid crystalline nanogels using Poloxamer. In vitro, the skin was pretreated with LFU until skin resistivity of ∼1 KΩ.cm2 using the various coupling media followed by evaluation of DOX penetration from DOX-nanogel and SLN-DOX in skin layers. Squamous cell carcinoma (SCC) induced in mice was LFU-treated using the nanogel with the LFU tip placed 5 mm or 10 mm from the tumor surface, followed by DOX-nanogel application. LFU with nanogel coupling achieved larger LTR areas than LFU with SLN coupling. In LFU-pretreated skin, DOX-nanogel significantly improved drug penetration to the viable epidermis, while SLN-DOX hindered drug transport through LTR. In vivo, LFU-nanogel pretreatment with the 10 mm tip distance induced significant tumor inhibition and reduced tumor cell numbers and necrosis. These findings suggest the importance of optimizing nanoparticle-based formulations and LFU parameters for the clinical application of LFU technology in skin tumor treatment.
Graphical abstract
Keywords: Low frequency ultrasound Doxorubicin Skin cancer therapy Sonophoresis Topical treatment.
Investigation of the antimicrobial effect of anodic iontophoresis on Gram-positive and Gram-negative bacteria for skin infections treatment
Highlights
- E. coli is more susceptible to iontophoretic parameter changes than S. epidermidis
- Iontophoresis altered bacteria morphology and induced high rates of E. coli death.
- Anodic iontophoresis can control Gram-negative bacterial proliferation in wounds.
Abstract
Iontophoresis, a non-invasive application of a constant low-intensity electric current, is a promising strategy to accelerate wound healing. Although its mechanisms are not yet fully elucidated, part of its action seems related to inhibiting bacteria growth. This work aimed to investigate the antimicrobial effect of iontophoresis using Staphylococcus epidermidis and Escherichia coli strains, Gram-positive and Gram-negative bacteria, respectively. Anodic iontophoresis was applied to each bacterial suspension using Ag/AgCl electrodes, and bacteria viability was evaluated after 24 h incubation by counting colony-forming units. A Quality-by-Design approach was performed to assess the influence of the iontophoresis’ intensity and application time on bacterial viability. Cell morphology was evaluated by scanning electron microscopy. Iontophoresis showed antimicrobial effects on the Gram-positive bacteria only at 5 mA and 60 min application. However, a linear relationship was observed between intensity and application time for the Gram-negative one, causing drastic morphological changes and up to 98 % death. The cell wall of Gram-negative bacteria seems more susceptible to disorganization triggered by iontophoresis-induced ion transport than Gram-positive ones. Therefore, anodic iontophoresis can be a powerful ally in controlling Gram-negative bacteria proliferation in wounds.
Graphical abstract
