Oxidative stress and its possible relation to lower urinary tract functional pathology.

Oxidative stress is considered to reflect an imbalance between the systemic manifestation of reactive oxygen and nitrogen species (RONS) and a biological system's ability to readily detoxify the reactive intermediates or to repair the resulting damage. RONS are not only harmful agents that cause oxidative damage in pathologies; they also have important roles as regulatory agents in a range of biological phenomena. They are normally generated as by-products of oxygen metabolism; however, environmental stressors (i.e., ultraviolet radiation, ionizing radiations, pollutants, heavy metal, and xenobiotics) contribute to greatly increase RONS production. Several antioxidants have been exploited in recent years for their actual or supposed beneficial effect against oxidative stress, but to date, none has been approved for any indication because they have not met the criteria of efficacy for drug approval. The present review discusses the concept of oxidative stress, how to measure it, how to prevent it, and its occurrence in different organ systems with special reference to the lower urinary tract.