Hepatic Oxidative Stress: Role of Liver Biopsy

Free radicals are highly reactive substances produced continuously during metabolic processes. They participate mainly in physiological events such as the immune response, metabolism of unsaturated fatty acids, and inflammatory reaction. The balance between free radicals and antioxidants is disrupted in many diseases. This disruption may be attributed to a number of factors such as the inability of the cells to produce sufficient amounts of antioxidants, the nutritional deficiency of minerals or vitamins, and the excess production of reactive oxygen species (Abd Ellah, 2010). Free radical excess results in impairment of DNA, enzymes, and membranes and induces changes in the activity of the immune system and in the structure of basic biopolymers which, in turn, may be related to mutagenesis and aging processes (Poli, 1993). The involvement of oxidative stress in the pathogenesis of hepatic dysfunction in human (Comporti, 1998; Poli et al.,1987; Zern et al., 1990; Poli, 1993; Tsai et al., 1993; De Maria et al., 1996; Gonzalez-Correa et al., 1997; Paradis et al., 1997; Feher et al., 1998; Wallace & Miller, 2000; Spirli et al., 2001; Alpini et al., 2002; Cesaratto et al., 2004; Jabłonowska et al., 2005) and animals (Khan et al., 1987; Mudronň et al., 1997; 1999; Spolarics, 1999; Sansinanea et al., 2000; Abd Ellah et al., 2002; 2004, 2007, 2008, 2009, 2010) has been investigated for many years. Some of the liver diseases were associated with increase (Farinati et al., 1995; Abd Ellah et al., 2002, 2008) or decrease (Mudroň et al., 1997; Barbaro et al., 1999; Abd Ellah et al., 2004; Videla et al., 2004; Czeczot et al., 2006) antioxidants contents. Usually hepatic antioxidants increased at the beginning of hepatic disease and decreased in severe hepatic injury. The advantages of measuring hepatic oxidative status in liver biopsy are that it helps in diagnosis of hepatic dysfunction, reflects the degree of deterioration in the liver tissues, and helps to determine the severity of hepatic injury, and also, aid in recommending antioxidant’s therapy in patients that had a hepatic disease with derangement in hepatic antioxidant constituents. The main purpose of the current article is to explore the value of liver biopsy as a tool for detection of hepatic oxidative stress. A focus was done on different types of free radicals, antioxidants, lipid peroxidation, and hepatic and blood oxidative status in hepatic dysfunction.