Lipids oxidative damage

Fig. 16.1 Progression of oxidation in a food system from formation of radicals through primary and secondary lipid oxidation products to protein damage.

Merry, P., Grootveld, M., Lunec, J. and Blake, D.R (1991). Oxidative damage to lipids within the inflamed human joint provides evidence of radical-mediated hypoxic-reperfusion injury. Am. J. Clin. Nutr. 53, 362S-369S. 

Patients in which oxidative damage may be an important aetiological factor cataract formation include those with Down s syndrome, since there is now evidence that they have increased indices of free-radical activity and lipid peroxidation. It has been su ested that this is due to the increased levels of Cu/Zn-SOD (carried on chromosome 21) generating increased concentrations of hydrogen peroxide (Bras etal., 1989). In the presence of superoxide radicals these produce highly reactive hydroxyl radicals. 

It is now widely appreciated that polyunsaturated fatty acids (PUFAs) are highly susceptible to oxidative damage. Indeed, the process of lipid peroxidation was broadly defined as the oxidative deterioration of polyunsaturated lipids by Tappel (1979). The presence of a double... 

Sujak, A., J. Gabrielska, W. Grudzinski, R. Bore, P. Mazurek, and W.I. Gruszecki. 1999. Lutein and zeaxanthin as protectors of lipid membranes against oxidative damage The structural aspects. Arch. Biochem. Biophys. 371 301-317. 

Vitamins (C and E), polyphenolic compounds, and carotenoids are the main groups of antioxidants present in fruits and vegetables. Vitamins are single molecules, but polyphenols and carotenoids are made up of hundreds of compounds with a wide range of structures and molecular masses. The intake of these antioxidants can lead to sustained reduction of the kind of oxidative damage to lipids, proteins, and DNA that is associated with the development of chronic diseases (Evans and Halliwell 2001). 

Oxidative damage to membrane polyunsaturated fatty acids leads to the formation of numerous lipid peroxidation products, some of which can be measured as index of oxidative stress, including hydrocarbons, aldehydes, alcohols, ketones, and short carboxylic acids. 

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