Biodegradation of Metallic Biomaterials: Its Relation with the Generation of Reactive Oxygen Species

Abstract

Some specific clinical problems, particularly those related to orthopedic trauma and some cardiovascular diseases need only temporary support for healing. This support can be provided by biodegradable metallic materials such as Mg-, Fe- based alloys that avoid some of the side effects of traditional biomaterials. They are expected to support healing process of a diseased tissue or organ and slowly degrading after fulfilling their function. However, the excess of metal ions may catalyze the formation of reactive oxygen species (ROS) and nitrogen (RNS). An increase in the intracellular levels of free metal ions affects the normal balance ROS-antioxidant. ROS could cause lipid peroxidation with changes in the composition and fluidity of cell membrane and alterations in other macromolecules as proteins and DNA. Considering that the concentration of metal ions can reach high values in the biomaterial-tissue interface inducing ROS generation it is important to evaluate the possible adverse effects of the degradation products of biodegradable biomaterials.