Influence of simulated gastrointestinal conditions on particle-induced cytotoxicity and interleukin-8 regulation in differentiated and undifferentiated Caco-2 cells

Abstract

Novel aspects of engineered nanoparticles offer many advantages for optimising food products and packaging. However, their potential hazards in the gastrointestinal tract require further investigation. We evaluated the toxic and inflammatory potential of two types of particles that might become increasingly relevant to the food industry, namely SiO₂ and ZnO. The materials were characterised for their morphology, oxidant generation and hydrodynamic behaviour. Cytotoxicity and interleukin-8 mRNA and protein expression were evaluated in human intestinal Caco-2 cells. Particle pretreatment under simulated gastric and intestinal pH conditions resulted in reduced acellular ROS formation but did not influence cytotoxicity (WST-1 assay) or IL-8 expression. However, the differentiation status of the cells markedly determined the cytotoxic potency of the particles. Further research is needed to determine the in vivo relevance of our current observations regarding the role of particle aggregation and the stage of intestinal epithelial cell differentiation in determining the hazards of ingested particles.

Impact of food components during in vitro digestion of silver nanoparticles on cellular uptake and cytotoxicity in intestinal cells

“…Previous publications such as Böhmert et al (2014) and Gerloff et al (2013) show that the artificial in vitro : Cellular uptake of silver nanoparticles into Caco-2 cells exposed to 20 μg/ml undigested silver nanoparticles and digested silver nanoparticles with and without food components after 24 h as well as corresponding ion concentrations (∼10% ion release). Data represent mean and standard deviation (n = 6).…”

“…However, digestion did not remarkably affect the cytotoxic potential of nanoparticles. Gerloff et al (2013) described a protein-free digestion of SiO 2 and ZnO nanoparticles followed by viability testing in Caco-2 cells via WST-1. They also showed no digestionspecific influence.…”

“…The results of different in vitro digestion studies with nanoparticles suggest that they reach the intestine in nano form, but the next step, i.e. the absorption of the digested particles by the intestinal barrier, has not been investigated (Gerloff et al, 2013;McCracken et al, 2013). Similarly, data about cytotoxicity of particles digested in the presence of food components are lacking.…”

“…Similar digestion models have been used in studies testing food-relevant metallic nanoparticles, e.g. silica (Peters et al, 2012), silver nanoparticles (Walczak et al, 2013), as well as ZnO and SiO 2 (Gerloff et al, 2013), to analyze changes in nanoparticle cytotoxicity and reactive oxygen species production or aggregation/agglomeration behavior. The results of different in vitro digestion studies with nanoparticles suggest that they reach the intestine in nano form, but the next step, i.e.…”

Minimal Intestinal Epithelial Cell Toxicity in Response to Short- and Long-Term Food-Relevant Inorganic Nanoparticle Exposure

“…43 Silica nanoparticle (NP) uptake by Caco-2 cells by elemental analysis of the cells has been reported, although surface binding versus internalization is not readily distinguished by this method. 37 Internalization of TiO2 NP in Caco-2 cells has also been reported. 9…”