The Janus Face of Stress on Reproduction: From Health to Disease

Figure 3

Stress at cellular level: an unbalance between production of free radicals (e.g., reactive oxygen species (ROS)) and antioxidant defenses inducing oxidative stress in the cells. Although oxidative stress is widely accepted as an important pathogenic mechanism in different diseases, yet ROS are physiological mediators of transcription control and in many cells (e.g., leukocytes) ROS are protection factors against infectious stimuli. The complete elimination of free radicals would thus disrupt, rather than extend, the normal functioning of the body.