Endogenous anti-oxidants in pregnancy and preeclampsia.

Oxidative stress has been implicated in a wide variety of diseases and degenerative states including cancer, rheumatoid arthritis, cardiovascular disease and ageing. There is now considerable evidence to suggest that pregnancy leads to the generation of an increased oxidative burden, but whether this overwhelms the anti-oxidant capacity within the placenta and/or the peripheral circulation remains a point of conjecture. There is little doubt that oxidative stress is a significant contributor in the pathogenesis of preeclampsia. The use of exogenous anti-oxidants such as vitamins C and E in the prevention of preeclampsia is the subject of several large clinical trials currently being conducted in many countries around the world. The results of these studies are eagerly awaited, but what of the endogenous anti-oxidant systems that have evolved to combat the oxidative burden associated with living in an aerobic environment? This review will focus on several important anti-oxidant enzyme systems, their role in pregnancy and the evidence to suggest that endogenous anti-oxidants are important in the development of complications of pregnancy such as preeclampsia.