Xenobiotics, Oxidative Stress, Free Radicals Vs. Antioxidants: Dance Of Death to Heaven's Life

A xenobiotic is a compound that is foreign to the body. Xenobiotics can produce a variety of biological effects, including pharmacologic responses, toxicity, genes, immunologic reactions and cancer. Oxidative stress is a leading cause to damage cells by oxidation. The rate at which oxidative damage is induced (input) and the rate at which it is efficiently repaired and removed (output). A free radical is an atom or molecule that has one or more unpaired electron(s). These are highly reactive species capable of wide spread, indiscriminate oxidation and peroxidation of proteins, lipids and DNA which can lead to significant cellular damage and even tissue and/or organ failure. Antioxidants are molecules that slow or prevent the oxidation other chemicals. Oxidation reactions can involve the production of free radicals which can form dangerous chain reactions. Antioxidants can terminate these chain reactions by removing radical intermediates and can inhibit other oxidation reactions by being oxidized themselves. Antioxidants are often reducing agents such as thiols or phenols. Therefore, we need antioxidants to ensure our defence mechanism for neutralizing harmful radicals.