Chapter 6 - Heavy metals and free radical-induced cell death mechanisms

Abstract

Listen

Translate article

Heavy metals with free radicals and their risky role in organisms of biological systems are discussed. Among the heavy metals, As, Cd, Pb, Cr, Fe, Cu, Hg, and Ni are of major concern, and can induce the generation of reactive radicals and cause cellular damage via depletion of enzyme activities through lipid peroxidation and reaction with nuclear proteins and DNA. As and Cd are classified as human carcinogens. Reactive oxygen species (ROS) and free radicals in general are essential for cell signaling and other vital physiological functions; however, excessive amounts can cause alteration in cellular reduction-oxidation (redox) balance, and disrupt normal biological functions. When there is an imbalance between the activities of ROS and antioxidant/scavenging defense systems, oxidative stress occurs. Protein synthesis can be disturbed at many levels of toxic metals at a variety of mechanisms by affecting either the structure of nucleic acid metabolism, or the protein-forming system itself. Correlation between environmental exposures and nutritional status is complex. Thirty-five metals pose a threat to human health, 23 of which are heavy metals. Manufacturing and industrial facilities are often guilty of releasing toxic metals into the environment. The role of free radicals in normal cellular functions and different pathological conditions has been a focus of pharmacological studies in the recent past.