Cadmium Chloride Induces DNA Damage and Apoptosis of Human Liver Carcinoma Cells via Oxidative Stress

International Journal of Environmental Research and Public Health

Anthony Skipper²  Jennifer N. Sims¹  Clement G. Yedjou²  Paul B. Tchounwou² 

[1] Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Bookline Avenue, Boston, MA 02215, USA;Molecular Toxicology Research Laboratory, NIH-Center for Environmental Health, College of Science, Engineering and Technology, Jackson State University, 1400 Lynch Street, Box 18540, Jackson, MS 39217, USA;

关键词: cadmium chloride;    HepG₂ cells;    cytotoxicity;    oxidative stress;    DNA damage;    apoptosis;   

DOI  :  10.3390/ijerph13010088

来源: mdpi

【 摘 要 】

Cadmium is a heavy metal that has been shown to cause its toxicity in humans and animals. Many documented studies have shown that cadmium produces various genotoxic effects such as DNA damage and chromosomal aberrations. Ailments such as bone disease, renal damage, and several forms of cancer are attributed to overexposure to cadmium.  Although there have been numerous studies examining the effects of cadmium in animal models and a few case studies involving communities where cadmium contamination has occurred, its molecular mechanisms of action are not fully elucidated. In this research, we hypothesized that oxidative stress plays a key role in cadmium chloride-induced toxicity, DNA damage, and apoptosis of human liver carcinoma (HepG₂) cells. To test our hypothesis, cell viability was determined by MTT assay. Lipid hydroperoxide content stress was estimated by lipid peroxidation assay. Genotoxic damage was tested by the means of alkaline single cell gel electrophoresis (Comet) assay. Cell apoptosis was measured by flow cytometry assessment (Annexin-V/PI assay). The result of MTT assay indicated that cadmium chloride induces toxicity to HepG₂ cells in a concentration-dependent manner, showing a 48 hr-LD₅₀ of 3.6 µg/mL. Data generated from lipid peroxidation assay resulted in a significant (p < 0.05) increase of hydroperoxide production, specifically at the highest concentration tested. Data obtained from the Comet assay indicated that cadmium chloride causes DNA damage in HepG₂ cells in a concentration-dependent manner. A strong concentration-response relationship (p < 0.05) was recorded between annexin V positive cells and cadmium chloride exposure. In summary, these in vitro studies provide clear evidence that cadmium chloride induces oxidative stress, DNA damage, and programmed cell death in human liver carcinoma (HepG₂) cells.

【 授权许可】

CC BY   
© 2016 by the authors; licensee MDPI, Basel, Switzerland.