ABSTRACT
Located at the interface between the body and the environment, the stratum corneum (SC) is frequently and directly exposed to a pro-oxidative environment, including air-pollutants, ultraviolet solar radiation (UVR), chemical oxidants, and microorganisms (1-3). To counteract oxidative injury, the human skin is equipped with a network of enzymatic and non-enzymatic antioxidant systems (4). An imbalance between oxidative attack and antioxidant defense systems results in tissuespecific oxidative modifications of macromolecules and is referred to as ‘‘oxidative stress.’’ The composition and structure of the SC lipid and protein play a key role in determining barrier integrity, which is essential for skin moisturization, normal desquamation, and healthy skin condition (5,6). As oxidative lipid and protein modifications commonly result in structural or functional loss, antioxidant barrier systems are believed to play an important role in maintaining barrier integrity. However, while many unique histological, biophysical, and biochemical features of the SC have been known for long, its redox properties have only recently become the subject of systematic basic research. Recent studies have revealed the existence of redox gradients in the human SC. The aim of this chapter is to provide a brief overview on the relevant data available on this emerging field of research.
