Effects of Cerium Oxide and Selected Heavy Metals on the Induction of Cell Death Via Oxidative Stress-Mediated DNA Damage

Abstract

Oxidative stress is a condition that can lead to cell death in humans and is defined as an increase in reactive oxygen species (ROS) in the body. Several heavy metals, such as copper sulfate, lead acetate, and zinc acetate, are capable of causing oxidative stress. However, researchers have not yet identified the precise mechanism through which these heavy metals induce oxidative stress. Some heavy metals, including cerium oxide, iron, cobalt, vanadium, and arsenic exhibit antioxidant properties. This study was therefore conducted to compare the effects of cerium oxide and selected heavy metals on cell death induction via oxidative stress-mediated DNA damage. Cerium oxide, copper sulphate, zinc acetate, and lead acetate were tested for their scavenging abilities using DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) and alkaline DMSO (dimethylsulfoxide) methods. To determine whether the heavy metals could affect kidney cells, toxicity assays on Vero cells were performed. Ultraviolet light was used to induce oxidative stress in Vero and bacterial cells. To investigate the effects of heavy metals on UV radiation-induced oxidative damage, DNA nicking assays were carried out. The results revealed that all the heavy metals exhibited oxidative stress. Only cerium oxide neutralized free radicals and was observed to have antioxidant properties. Also, heavy metals normally produce oxidative stress when exposed to UV radiation, but heavy metals such as cerium oxide prevent oxidative damage. The findings of this study reveal that cerium oxide has great potential for the treatment of oxidative stress-induced DNA damage.