Iron overload and lipid peroxidation in biological systems

PAULA M. GONZÁLEZ, NATACHA E. PILONI AND SUSANA PUNTARULO

Lipid Peroxidation

InTech

Lugar: Rijeka; Año: 2012; p. 89 - 109

Since the chemical properties of Fe constitutes limitations to the cellular accumulation of this element, storage of Fe in tissues includes a network of transporting and binding proteins, in addition to the presence of a labile Fe pool (LIP). To cope with the insolubility and potential toxicity of Fe, molecules such as ferritins, are involved in oxidative protection by sequestering Fe. The Fe forming the LIP can act catalytically to generate active oxygen radicals that cause severe damage to membranes, proteins, and DNA. Oxidative damage to lipids depends on the nature of the oxidant, the type of lipid, and the severity of the oxidation. Since a variety of stable products are formed, several assays have been developed over the years to assess these products in order to evaluate lipid peroxidation. The determination of both, malondialdehyde formation by the thiobarbituric acid reactive substances test (TBARS) and lipid radical generation by electron paramagnetic resonance (EPR) spectroscopy, have shown the capacity of detecting lipid radical peroxidation, in animal and plant tissues from organisms exposed to Fe overload. This chapter will be dedicated to overview the Fe-related alterations in oxidative metabolism produced in photosynthetic and non-photosynthetic organisms after experimental exposure to excess Fe employing different protocols of administration. Data assessing lipid peroxidation post-treatment both, as TBARS generation and/or EPR detection of lipid radicals, are reviewed in a wide range of biological systems.