ABSTRACT
Reactive oxygen species (ROS) are produced during the normal cellular metabolism and are essential in carrying out the cell functions. In semen, ROS are produced by spermatozoa and leukocytes. This chapter discusses the cellular and subcellular sources of ROS in semen and their regulation at the molecular level. Physiological levels of ROS are essential for normal sperm function; however, an imbalance between ROS and antioxidant levels causes oxidative stress (OS), which affects sperm function. The pathological effects of elevated levels of ROS on sperm parameters such as membrane function, motility, capacitation, acrosome reaction, and sperm-zona binding capacity are discussed in great details. Further, the OS-induced sperm apoptotic pathway explaining the key factors involved in the cell death has been deliberated. Finally, future directions and recommendations regarding the treatment of OS are discussed.
