Low cytotoxicity of solid lipid nanoparticles inin vitroandex vivolung models

Abstract

The aim of this study was to investigate the potential cytotoxicity of solid lipid nanoparticles (SLN) for human lung as a suitable drug delivery system (DDS). Therefore we used a human alveolar epithelial cell line (A549) and murine precision-cut lung slices (PCLS) to estimate the tolerable doses of these particles for lung cells. A549 cells (in vitro) and precision-cut lung slices (ex vivo) were incubated with SLN20 (20% phospholipids in the lipid matrix of the particles) and SLN50 (50% phospholipids in the lipid matrix of the particles) in increasing concentrations. The cytotoxic effects of SLN were evaluated in vitro by lactate dehydrogenase (LDH) and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Vitality of lung slices was controlled by staining with calcein AM/ethidium homodimer 1 using confocal laser scanning microscopy and followed by quantitative image analysis with IMARIS software. A549 cell line revealed a middle effective concentration (EC(50)) for MTT assay for SLN20 of 4080 microg/ml and for SLN50 of 1520 microg/ml. The cytotoxicity in terms of LDH release showed comparable EC(50) values of 3431 microg/ml and 1253 microg/ml for SLN20 and SLN50, respectively. However, in PCLS we determined only SLN50 cytotoxic values with a concentration of 1500 microg/ml. The lung slices seem to be a more sensitive test system. SLN20 showed lower toxic values in all test systems. Therefore we conclude that SLN20 could be used as a suitable DDS for the lung, from a toxicological point of view.

In vitrolung slices: a powerful approach for assessment of lung pathophysiology

“…In addition, lung slices can be prepared from animals that are exposed to pollutants in vivo; this tissue can then be used to study toxicant-related changes in cellular respiration, glucose consumption, lipid metabolism and other parameters [2]. The lung-slice model has most recently been used to study lipid nanoparticle toxicity in mice [41].…”

Applicability of rat precision-cut lung slices in evaluating nanomaterial cytotoxicity, apoptosis, oxidative stress, and inflammation

“…Pulmonary morphology and organ-typical cell-cell structures enabling intercellular communication are maintained for up to 70 h (BéruBé et al, 2009;Martin et al, 1996). Thereby reflecting physiological pulmonary histology, the ex vivo PCLuS system has already been used to study a variety of scientific problems relating to the lung, ranging from pharmacological effects on the airway system (Martin et al, 1996), pulmonary function (Martin et al, 2000), and toxicological effects of bulk or nanoscale substances (Nassimi et al, 2009). Results from PCLuS studies have been evaluated to be precise and reproducible (Martin et al, 1996).…”

Adenosine monophosphate is elevated in the bronchoalveolar lavage fluid of mice with acute respiratory toxicity induced by nanoparticles with high surface hydrophobicity

“…Most of the studies of low-toxicity nanomaterials have been conducted using rigid, crystalline, insoluble materials, whereas there has been less research on the response of the respiratory system to the administration of organic nanomaterials (Beyerle et al, 2011;Dailey et al, 2006;Harush-Frenkel et al, 2010;Liu et al, 2009;Nassimi et al, 2009), sometimes referred to as soft nanomaterials (Nalwa, 2009). Organic nanomaterials are increasingly being developed as inhaled nanomedicines or components of aerosol-based consumer products, e.g.…”