RESUMO
Graphene derivatives are expected to have a great impact in a wide range of applications, among them as food packaging materials. This is one of the sources of potential human oral exposure to them. However, studies devoted to investigating their putative toxic effects at the intestinal level are underrepresented in the scientific literature. Thus, this study aimed to investigate the in vitro toxicity of reduced graphene oxide (rGO) and graphene oxide (GO) in the human intestinal Caco-2 cell line. rGO and GO were firstly characterized and later, cell viability was assessed after exposure to 0-250 µg/mL rGO/GO for 24 and 48 h. Internalization was evidenced for both materials using transmission electron microscopy. A mean effective concentration (24 h) of 176.3 ± 7.6 µg/mL for cytotoxicity was obtained for rGO, whereas GO did not induce any change at the concentration range evaluated. However, both of them altered oxidative stress biomarkers, causing increased reactive oxygen species (ROS) and depletion of the glutathione content (GSH) after exposures up to 24 h. Further studies, particularly with rGO, are required to elucidate their toxicity profile in experimental models relevant for oral exposures.
RESUMO
Recientemente, el interés por el óxido de grafeno reducido (OGr) se ha visto incrementado debido a sus numerosas propiedades. Considerando que el uso de estos materiales ha aumentado en los últimos años, esto puede suponer un mayor riesgo para la salud humana. La vía oral es una de las principales rutas de exposición, por lo que es importante determinar cuáles son los principales efectos tóxicos sobre el sistema hepato-gastrointestinal. En este sentido, el objetivo de este estudio es revisar los posibles efectos tóxicos in vitro del OGr en las principales líneas celulares de los sistemas intestinal y hepático. Los resultados muestran que el OGr podría ser tóxico en modelos in vitro; sin embargo, son necesarios un mayor número de investigaciones para determinar los posibles mecanismos de toxicidad. (AU)
Recently, the interest in reduced graphene oxide (rGO) has increased due to its myriad of properties. Considering the higher use of this material in the last years, it is important to evaluate its potential risk on human health. The oral pathway is one of the main exposure routes, therefore, it is important to assess its toxic effects on the hepato-gastrointestinal system. In this sense, the aim of this study is to review the potential in vitro toxic effects of rGO on gastrointestinal and liver cell lines. The results obtained showed that rGO could be toxic in in vitro models; however, further toxicological studies are required to define its mechanisms of toxicity. (AU)
