Molecular role of oxidative stress and antioxidant defense in human diseases

Oxidative imbalance is now viewed as an important biological process in the development and progression of various pathological conditions. Oxidative imbalance is the process by which the rate of production of reactive oxygen species (ROS) outstrips the capacity of the cellular protective mechanisms, which maintain the equilibrium of the cellular redox state. Oxidative activity, if sustained, can damage cellular macromolecules, interfere with molecular signaling, and accelerate cellular dysfunction. This review presents an updated discussion of the molecular mechanisms of oxidative damage, the role of the antioxidant defense system, and the clinical relevance of oxidative imbalance in various diseases. New diagnostic markers and therapeutic interventions in oxidative imbalance are also discussed to present an updated perspective of the current knowledge in the field of oxidative biology in health and disease.