Liver Toxicity of Cadmium Telluride Quantum Dots (CdTe QDs) Due to Oxidative Stress in Vitro and in Vivo

Abstract

With the applications of quantum dots (QDs) expanding, many studies have described the potential adverse effects of QDs, yet little attention has been paid to potential toxicity of QDs in the liver. The aim of this study was to investigate the effects of cadmium telluride (CdTe) QDs in mice and murine hepatoma cells alpha mouse liver 12 (AML 12). CdTe QDs administration significantly increased the level of lipid peroxides marker malondialdehyde (MDA) in the livers of treated mice. Furthermore, CdTe QDs caused cytotoxicity in AML 12 cells in a dose- and time-dependent manner, which was likely mediated through the generation of reactive oxygen species (ROS) and the induction of apoptosis. An increase in ROS generation with a concomitant increase in the gene expression of the tumor suppressor gene p53, the pro-apoptotic gene Bcl-2 and a decrease in the anti-apoptosis gene Bax, suggested that a mitochondria mediated pathway was involved in CdTe QDs’ induced apoptosis. Finally, we showed that NF-E2-related factor 2 (Nrf2) deficiency blocked induced oxidative stress to protect cells from injury induced by CdTe QDs. These findings provide insights into the regulatory mechanisms involved in the activation of Nrf2 signaling that confers protection against CdTe QDs-induced apoptosis in hepatocytes.

Leaching of cadmium and tellurium from cadmium telluride (CdTe) thin-film solar panels under simulated landfill conditions

“…Furthermore, two individuals that were mistakenly injected with sodium tellurite died after 6 h of exposure [4]. The toxicity of CdTe itself is poorly characterized, but several studies have shown that CdTe [6, 7] and CdTe quantum dots are cytotoxic to mammalian cells [8-10]. CdTe can cause severe pulmonary inflammation and fibrosis [6].…”

Impairments of spatial learning and memory following intrahippocampal injection in rats of 3-mercaptopropionic acid-modified CdTe quantum dots and molecular mechanisms

“…The concentrations for QDs used here were selected based on preliminary experiments and a series of previous studies. 7,9,12 animals and treatment A total of 49 male Wistar rats aged 6 weeks with an average body weight of 130-150 g were purchased from Shanghai Super B&K Laboratory Animal Corp Ltd (Shanghai, People's Republic of China). Seven rats were in each group.…”

Review of toxicological effect of quantum dots on the liver

“…Meanwhile, the QDs caused an elevation in the ratio of GSH/oxidised glutathione at12 weeks, but significantly reduced at 16 weeks in QD705‐treated animals, which reflected the oxidative stress (Lin et al, ). Other studies have also proven that QDs can lead to a significant increase in the levels of the ROS or ·OH, and changes in the concentration or activity of glutathione peroxidase, CAT and SOD (Serban et al, ; S. Wang et al, ; Y. Yang, T. Zhao et al, ; Yang et al, ; Zhang et al, ).…”

“…Studies have demonstrated that QDs can cause oxidative stress on various hepatocyte models in vitro. Studies have shown that QDs caused oxidative stress in liver tissues through changes in antioxidant enzyme activity and content, and trace element content related to antioxidant enzymes (Lin et al, ; Zhang et al, ). Lin et al studied ICR mice injected intravenously with CdTe/ZnS (40 and 160 pmol per mouse).…”