Relationship of Lead with Free Radicals, Reactive Oxygen Species, Oxidative Stress and Antioxidant Enzymes

Abstract

Heavy metals, which are high in the environment, are substances that have a high toxic effect even at low concentrations. Heavy metals taken into the organism through mouth, respiration and skin cannot be eliminated by the body's excretory pathways. In addition, since they have a durable structure, they participate in the food chain and accumulate in various body tissues. With the increase in industrial activities, heavy metal pollution has also emerged and has increased day by day. Lead is an element that is widely used in industry because it has a low melting temperature. However, it is known that lead, like other heavy metals, has an effect on problems such as environmental pollution and health problems. Occupational diseases such as lead poisoning occur as a result of direct exposure to lead. Direct exposure in this way can also cause death. Lead causes undesirable conditions such as increase of reactive oxygen species (ROS), emergence of oxidative stress and weakening of antioxidant system. Lead disrupts the prooxidant/antioxidant ratio. As a result, effects such as an increase in ROS and thus damage to the basic components of the cell such as lipid, protein and nucleic acid are observed.In particular, lead inhibits enzymes and prevents some enzymes from acting as antioxidants. As a result of exposure to lead, there is a decrease in the defense abilities of antioxidant enzymes such as catalase (CAT), superoxide dismutase (SOD), glutathione (GSH) and ascorbic acid in blood and tissues. Lead increases lipid peroxidation and thus causes oxidative damage. Evaluation of the effect of lead at the cellular level is important in terms of developing solutions for the toxic effects of lead. In this study, the effect of lead on the cellular level in the organism and its effects on free radicals, ROS and oxidative stress were evaluated.