CHAPTER 32: Selenium, the Placenta and Trophoblast Mitochondrial Oxidative Stress

The human placenta is central to a healthy pregnancy and the growth of a strong and robust baby. There is considerable evidence to indicate that a healthy start to life is essential to lifelong health and poor in utero development can impact on the incidence of chronic disease in adulthood. Placental tissue is highly aerobic and placental mitochondria are particularly prone to oxidative stress. The endogenous antioxidants glutathione peroxidase and thioredoxin reductase play an important role in negating the detrimental effects of reactive oxygen and nitrogen species that are generated during normal oxidative metabolism, but are produced excessively in some disease scenarios, including complications of pregnancy. These enzymes are selenoproteins and selenium supplementation has been shown to boost their expression and activity, in turn conveying protection to placental cells from oxidative stress. This review will present data on the importance of selenium in placental health and argue that selenium status is a very important consideration in pregnancy. Selenium is an essential trace element in human nutrition and integral to providing a healthy start to life.