Oxidative Stress in Liver Diseases

Oxidative stress corresponds to an imbalance between the rate of oxidant production and that of their degradation. The main biological targets of free radicals are proteins, lipids and DNA. Protein oxidation leads to loss of function or premature degradation in proteasomes. Lipid peroxidation, occurring mostly in the plasma membrane or the stratum corneumthe most superficial layer of the epidermisalters the physical properties of cell membranes or the epidermis, and thereby their biological function. Oxidation of DNA can lead to gene mutation, and thus abnormal protein synthesis, alteration in gene expression, apoptosis and cell death. An oxidative stress is often associated to all kinds of diseases, although it is not always easy to determine whether it is a cause or a consequence of the observed condition. Liver fibrosis, hepatocellular carcinoma, alcoholism and non alcoholic fatty liver were the main diseases that will be discussed in this work.