8-OHdG: A Biomarker for Lead and Cadmium Toxicity

Ecological and manmade behaviors, such as insufficient waste management and a continual rise in industry, are the primary causes of heavy metal exposure. Heavy metals are distinguished by their great hydrophilic nature and fast assimilation by all biological entities. A discrepancy in the formation and aggregation in reactive oxygen species (ROS) causes oxidative stress, and an excess of ROS has a negative influence on cell function. High ROS levels cause oxidative damage to enzymes, lipids, and DNA, culminating in functional and structural cellular changes. To restore DNA damage, the primary excision repair process is commonly performed, and oxidized byproducts are removed in urine. The interaction of both the hydroxyl radical, an essential oxygen-free radical, with DNA strand nucleobases such as guanine results in the creation of 8-hydroxy 2'-deoxyguanosine (8-OHdG). It serves as an oxidative DNA damaging marker, indicating the degree of DNA damage. Lead and Cadmium both influence membrane-linked systems such as membrane enzyme activity, solute transport throughout the bilayer, and signaling pathways, mostly causing kidney failure. This review focuses on the function of the 8-OHdG biomarker in estimating lead and cadmium poisoning.