The protective effects of melatonin on organisms against the environmental pollutants of heavy metal and non-metal toxins

Metal and non-metal toxins are primarily derived from the human industrial and agricultural activities. These toxins have substantially polluted our ecosystem and become a major threatening factor to our health. Metal or non-metal pollutants are highly toxic because they interact with biological macromolecules including DNA, proteins and membrane to induce oxidative stress. If they are not properly handled, these toxins will inevitably cause organ and tissue injuries in both animals and plants. To identify the effective remedies to detoxify these toxins becomes the urgent agenda for researchers. Accumulated evidence indicates that melatonin may be a suitable molecule for this purpose. Melatonin, a naturally occurring antioxidant, directly scavenges ROS or upregulates expressions of many antioxidant enzymes to indirectly reduces ROS. In addition, it also promotes the excretion of these metal or non-metal toxins from the body. The multiple protective mechanisms of melatonin effectively suppress the oxidative stress induced by the metal or non-metal toxins in animals or plants. Melatonin is an environmental-friendly molecule with low or none toxicity to animals or plants. It is a promising molecule which can be used to detoxify the environmental pollutants.